Dear Editor,The occurrence of concentrated pneumonia cases in Wuhan city,Hubei province of China was first reported on December 30,2019 by the Wuhan Municipal Health Commission(WHO,2020).The pneumonia cases were found...Dear Editor,The occurrence of concentrated pneumonia cases in Wuhan city,Hubei province of China was first reported on December 30,2019 by the Wuhan Municipal Health Commission(WHO,2020).The pneumonia cases were found to be linked to a large seafood and animal market in Wuhan,and measures for sanitation and disinfection were taken swiftly by the local government agency.The Centers for Disease Control and Prevention(CDC)and Chinese health authorities later determined and announced that a novel coronavirus(CoV),denoted as 2019-nCoV,had caused the pneumonia outbreak in Wuhan city(CDC,2020).Scientists from multiple groups had obtained the virus samples from hospitalized patients(Normile,2020).The isolated viruses were morphologically identical when observed under electron microscopy.展开更多
Liver fibrosis is a reversible wound-healing process aimed at maintaining organ integrity, and presents as the critical pre-stage of liver cirrhosis, which will eventually progress to hepatocellular carcinoma in the a...Liver fibrosis is a reversible wound-healing process aimed at maintaining organ integrity, and presents as the critical pre-stage of liver cirrhosis, which will eventually progress to hepatocellular carcinoma in the absence of liver transplantation. Fibrosis generally results from chronic hepatic injury caused by various factors, mainly viral infection, schistosomiasis, and alcoholism; however, the exact pathological mechanisms are still unknown. Although numerous drugs have been shown to have antifibrotic activity in vitro and in animal models, none of these drugs have been shown to be efficacious in the clinic. Importantly, hepatic stellate cells(HSCs) play a key role in the initiation, progression, and regression of liver fibrosis by secreting fibrogenic factors that encourage portal fibrocytes, fibroblasts, and bone marrow-derived myofibroblasts to produce collagen and thereby propagate fibrosis. These cells are subject to intricate cross-talk with adjacent cells, resulting in scarring and subsequent liver damage. Thus, an understanding of the molecular mechanisms of liver fibrosis and their relationships with HSCs is essential for the discovery of new therapeutic targets. This comprehensive review outlines the role of HSCs in liver fibrosis and details novel strategies to suppress HSC activity, thereby providing new insights into potential treatments for liver fibrosis.展开更多
Zircon LA-ICP MS U-Pb dating of six metamorphic rocks and a metagranite (breccia) from southern basement of the Songliao Basin are reported in order to constrain the formation ages of basement. The basement metamorphi...Zircon LA-ICP MS U-Pb dating of six metamorphic rocks and a metagranite (breccia) from southern basement of the Songliao Basin are reported in order to constrain the formation ages of basement. The basement metamorphic rocks in the Songliao Basin mainly consist of metagabbro (L45-1), amphibolite (SN117), metarhyolitical tuff (G190), sericite (Ser) schist (N103), chlorite (Chl) schist (T5-1), biotite (Bi)-actinolite (Act)-quartz (Q) schist (Y205), and metagranite (L44-1). The cathodoluminesence (CL) images of the zircons from metagabbro (L45-1) and metagranite (L44-1) indicate that they have cores of magmatic origin and rims of metamorphic overgrowths. Their U-Pb isotopic ages are 1808±21 Ma and 1873±13 Ma, respectively. The zircons with oscillatory zoning from amphibolite (SN117) and Chl schist (T5-1), being similar to those of mafic igneous rocks, yield ages of 274 ± 3.4 Ma and 264 ± 3.2 Ma, re-spectively. The zircons from metarhyolitical tuff (G190) and Ser schist (N103) display typical magmatic growth zoning and yield ages of 424 ± 4.5 Ma and 287 ± 5.1Ma, respectively. Most of zircons from Bi-Act-Q schist (Y205) are round in shape and different in absorption degree in the CL images, implying their sedimentary detritals. U-Pb dating yield concordant ages of 427 ± 3.1Ma, 455 ± 12 Ma, 696 ± 13 Ma, 1384±62 Ma, 1649±36 Ma, 1778±18 Ma, 2450±9 Ma, 2579±10 Ma, 2793±4 Ma and 2953±14 Ma. The above-mentioned results indicate that the Precambrian crystalline basement (1808―1873 Ma) exists in the southern Songliao Basin and could be related to tectonic thrust, and that the Early Paleozoic (424―490 Ma) and Late Paleozoic magmatisms (264―292 Ma) also occur in the basin basement, which are consistent with the ages of the detrital zircons from Bi-Act-Q schist in the basement.展开更多
Dear Editor, Human embryonic stem （ES） cells possess the potential to differentiate into all the cell types of the human body and provide potential applications in regenerative medicine . However, the concerns of i...Dear Editor, Human embryonic stem （ES） cells possess the potential to differentiate into all the cell types of the human body and provide potential applications in regenerative medicine . However, the concerns of immune rejection hamper transplantation therapies using human ES cells. To avoid the complications of immune rejection, diverse methods, such as somatic nuclear transfer （also called therapeutic cloning） and fusion of somatic ceils with human ES ceils , have been attempted to produce patient-specific pluripotent stem cells. Most of these approaches have resulted in little success. The generation of human iPS cells （induced展开更多
AIM To assess the possible roles of cytokines (TNF α, IFN γ, IL 6 and IL 8) in liver damage of hepatitis B. METHODS The serum TNF α, IFN γ, IL 6 and IL 8 were detected by ELISA in 66 patients with hepat...AIM To assess the possible roles of cytokines (TNF α, IFN γ, IL 6 and IL 8) in liver damage of hepatitis B. METHODS The serum TNF α, IFN γ, IL 6 and IL 8 were detected by ELISA in 66 patients with hepatitis B and 20 healthy blood donors. RESULTS TNF α and IL 6 in all types of clinical hepatitis B were significantly higher than those in healthy blood donors ( P <0 05); meanwhile the levels of TNF α, IFN γ, IL 6 and IL 8 in the patients with fulminant hepatitis B were much higher than those in the patients with acute hepatitis B ( P <0 05); the level of TNF α was positively correlated with the levels of IFN γ, Il 6 and IL 8 in all types of hepatitis B ( r IFN =0 24, r IL 6 =0 35, r IL 8 =0 44) and the TNF α, IFN γ, IL 6 and IL 8 were positively correlated with serum bilirubin ( P <0 05). Dynamic changes of these cytokines were observed in the course of acute and fulminant hepatitis. The level of IFN γ peaked in the initial period of acute hepatitis and early stage of hepatic coma in fulminant hepatitis; TNF α, IL 6 and IL 8 increased with exacerbation, and reached a peak when the liver damage was most serious, then decreased when patient conditions were improved. CONCLUSION The increased cytokines were related to the inflammation of liver cells and multiple factors may play certain roles in liver damage.展开更多
The Mianle tectonic zone (Mianle zone), an ancient suture zone in addition to the Shangdan suture in the Qinling-Dabie orogenic belt, marks an important tectonic division geo-logically separating north from south and ...The Mianle tectonic zone (Mianle zone), an ancient suture zone in addition to the Shangdan suture in the Qinling-Dabie orogenic belt, marks an important tectonic division geo-logically separating north from south and connecting east with west in China continent. To de-termine present structural geometry and kinematics in the Mianle tectonic zone and to recon-struct the formation and evolution history involving plate subduction and collision in the Qinling-Dabie orogenic belt, through a multidisciplinary study, are significant for exploring the mountain-building orogenesis of the central orogenic system and the entire process of the major Chinese continental amalgamation during the Indosinian.展开更多
In our experience patients undergoing circumcision are mostly concerned about pain and penile appearances. We conducted a prospective randomized trial to assess the benefits of a new disposable circumcision suture dev...In our experience patients undergoing circumcision are mostly concerned about pain and penile appearances. We conducted a prospective randomized trial to assess the benefits of a new disposable circumcision suture device （DCSD）. A total of 942 patients were equally divided into three groups （conventional circumcision, Shang ring and disposable suture device group）. Patients in the DCSD group were anesthetized with compound 5% lidocaine cream, the others with a 2% lidocaine penile block. Operation time, intra-operative blood loss, incision healing time, intra-operative and post-operative pain, the penile appearance and overall satisfaction degree were measured. Operation time and intra-operative blood loss were significantly lower in the Shang ring and suture device groups compared to the conventional group （P 〈 0.001）. Intra-operative pain was less in the suture device group compared With the other two groups （P 〈 0.001）; whereas post-operative pain was higher in the conventional group compared to the other two groups （P 〈 0.001）. Patients in the suture device （80.57%） and Shang ring （73,57%） groups were more satisfied with penile appearances compared with the conventional circumcision group （20.06%, P 〈 0.05）. Patients in suture device group also healed markedly faster than the conventional group （P 〈 0.01）. The overall satisfaction rate was better in the suture device group （78.66%） compared with the conventional （47.13%） and Shang ring （50.00%） groups （P 〈 0.05）. The combination of DCSD and lidocaine cream resulted in shorter operation and incision healing times, reduced intra-operative and post-operative pain and improved patient satisfaction with the cosmetic appearances.展开更多
Human placenta-derived mononuclear cells （MNC） were isolated by a Percoll density gradient and cultured in mesenchymal stem cell （MSC） maintenance medium. The homogenous layer of adherent cells exhibited a typical...Human placenta-derived mononuclear cells （MNC） were isolated by a Percoll density gradient and cultured in mesenchymal stem cell （MSC） maintenance medium. The homogenous layer of adherent cells exhibited a typical fibroblastlike morphology, a large expansive potential, and cell cycle characteristics including a subset of quiescent cells. In vitro differentiation assays showed the tripotential differentiation capacity of these cells toward adipogenic, osteogenic and chondrogenic lineages. Flow cytometry analyses and immunocytochemistry stain showed that placental MSC was a homogeneous cell population devoid of hematopoietic cells, which uniformly expressed CD29, CD44, CD73, CD105, CD166, laminin, fibronectin and vimentin while being negative for expression of CD31, CD34, CD45 and m-smooth muscle actin. Most importantly, immuno-phenotypic analyses demonstrated that these cells expressed class Ⅰ major histocompatibility complex （MHC-I）, but they did not express MHC-Ⅱ molecules. Additionally these cells could suppress umbilical cord blood （UCB） lymphocytes proliferation induced by cellular or nonspecific mitogenic stimuli. This strongly implies that they may have potential application in allograft transplantation. Since placenta and UCB are homogeneous, the MSC derived from human placenta can be transplanted combined with hematopoietic stem cells （HSC） from UCB to reduce the potential graft-versus-host disease （GVHD） in recipients.展开更多
LA-ICP-MS zircon U-Pb dating and geochemical data for the Late Paleozoic volcanic rocks from eastern and southeastern margins of the Jiamusi Massif are presented to understand the regional tectonic evolution. Zircons ...LA-ICP-MS zircon U-Pb dating and geochemical data for the Late Paleozoic volcanic rocks from eastern and southeastern margins of the Jiamusi Massif are presented to understand the regional tectonic evolution. Zircons from eight representative volcanic rocks are euhedral-subhedral in shape and dis- play striped absorption and fine-scale oscillatory growth zoning as well as high Th/U ratios (0.33―2.37), implying a magmatic origin. The dating results show that the Late Paleozoic volcanic rocks in the study area can be divided into two stages, i.e., the Early Permian (a weighted mean 206Pb/238U age of 288 Ma) and the Middle Permian volcanisms (a weighted mean 206Pb/238U age of 268 Ma). The former is com- posed mainly of basalt, basaltic-andesite, andesite and minor dacite. They are characterized by low SiO2 contents, high Mg# (0.40―0.59), enrichment in Na (Na2O/K2O = 1.26―4.25) and light rare earth elements (LREEs), relative depletion in heavy rare earth elements (HREEs) and high field strength ele- ments (HFSEs), indicating that an active continental margin setting could exist in the eastern margin of the Jiamusi Massif in the Early Permian. The latter consists mainly of rhyolite and minor dacite with high SiO2 (77.23%―77.52%), low MgO (0.11%―0.14%), enrichment in K2O (Na2O/K2O ratios < 0.80) and Rb, Th, U and depletion in Eu, Sr, P and Ti, implying a crust-derived origin. Therefore, it is proposed that the Middle Permian volcanic rocks could have formed under the collision of the Jiamusi and the Khanka Massifs.展开更多
Objective MicroRNAs （miRs） are attractive molecules to be considered as one of the blood-based biomarkers for neurodegenerative disorders such as Alzheimer＇s disease （AD）. The goal of this study was to explore th...Objective MicroRNAs （miRs） are attractive molecules to be considered as one of the blood-based biomarkers for neurodegenerative disorders such as Alzheimer＇s disease （AD）. The goal of this study was to explore their potential value as biomarkers for the diagnosis of AD.Methods The expression levels of exosomal miR-135a, -193b, and -384 in the serum from mild cognitive impairment （MCI）, dementia of Alzheimer-type （DAT）, Parkinson＇s disease with dementia （PDD）, and vascular dementia （VaD） patients were measured with a real-time quantitative reverse transcriptase PCR （qRT-PCR） method.Results Both serum exosome miR-135a and miR-384 were up-regulated while miR-193b was down-regulated in serum of AD patients compared with that of normal controls. Exosome miR-384 was the best among the three miRs to discriminate AD, VaD, and PDD. Using the cut-off value could better interpret these laboratory test results than reference intervals in the AD diagnosis. ROC curve showed that the combination of miR-135a, -193b, and -384 was proved to be better than a particular one for early AD diagnosis.Conclusion Our results indicated that the exosomal miRs in the serum were not only potential biomarker of AD early diagnosis, but might also provide novel insights into the screen and prevention of the disease.展开更多
AIM: To evaluate the abnormal immunity and gene mutation at precore 1896 site in patients with severe hepatitis-B.METHODS: This study included 23 patients with severe hepatitis-B, 22 patients with acute hepatitis-B an...AIM: To evaluate the abnormal immunity and gene mutation at precore 1896 site in patients with severe hepatitis-B.METHODS: This study included 23 patients with severe hepatitis-B, 22 patients with acute hepatitis-B and 20 controls.Mutation at precore 1896 site of HBV gene was confirmed with restriction fragment length polymorphism (RFLP) analysis.Cytokines including TNF-α, IFN-y, IL-6, and IL-8 were measured with ELISA, and T subgroups were detected with alkaline phosphatase anti alkaline phosphatase (APAAP) technique.RESULTS: In patients with severe hepatitis-B, the infective rate of HBV mutant strain was 52.5% (12/23), and only one patient with acute hepatitis-B was infected with the mutant strain. The percentage of CD8+ T lymphocyte was obviously lower (0.16±0.02%) and the ratio of CD4+/CD8+ was obviously higher (2.35±0.89) in mutant group than in wildtype group (0.28±0.05% and 1.31±0.18%, respectively,P＜0.01 or P＜0.05). The levels of cytokines in patients with severe hepatitis-B were higher (TNF-α 359.0±17.2 ng/L, IFNγ 234.7±16.5 ng/L, IL-6 347.5±31.3 ng/L, IL-8 181.1±19.6ng/L) than those in acute hepatitis-B (TNF-α 220.6±8.9ng/L, IFN-γ 174.9±12.0 ng/L, IL-6 285.8±16.5 ng/L, IL-8118.4±5.1 ng/L, P＜0.01 or 0.05). In patients with severe hepatitis-B, the levels of IFN-γ and IL-6 were higher in mutant group (273.4±26.6 ng/L, 387.7±32.5 ng/L) than in wild-type group (207.8±12.8 ng/L, 300.9±16.3 ng/L). The mortality of patients infected with HBV mutant strain was higher (100%)than that with wild-type (0.9%).CONCLUSION: In severe hepatitis-B, the infective rate of HBV mutant strain was high. The mutant strain induces more severe immune disorders in host, resulting in the activation of lymphocyte and release of cytokines. HBV DNA mutates easily in response to the altered immunity. Ultimately liver damage is more prominent.展开更多
Objective To review the recent developments in the mechanisms of glucocorticoids induced osteonecrosis of femoral head （ONFH） and introduce a new theory of ONFH.Data sources Both Chinese- and English-language litera...Objective To review the recent developments in the mechanisms of glucocorticoids induced osteonecrosis of femoral head （ONFH） and introduce a new theory of ONFH.Data sources Both Chinese- and English-language literatures were searched using MEDLINE （1997-2011）,Pubmed （1997-2011 ） and the Index of Chinese-language Literature （1997-2011 ）.Study selection Data from published articles about mechanisms of glucocorticoids induced ONFH in recent domestic and foreign literature were selected.Data extraction Data were mainly extracted from 61 articles which are listed in the reference section of this review.Results Glucocorticoids are steroid hormones secreted by the adrenal cortex that play a pivotal role in the regulation of a variety of developmental,metabolic and immune functions.However,high dose of exogenous glucocorticoids usage is the most common non-traumatic cause of ON FH.Glucocorticoids can affect the metabolisms of osteoblasts,osteoclasts,bone marrow stromal cells and adipocytes which decrease osteoblasts formation but increase adipocytes formation and cause ONFH finally.Conclusions Glucocorticoids affect the differentiation of mesenchymal stem cells,through activating or inhibiting the related transcript regulators of osteogenesis and adipogenesis.At last,the size and volume of mesenchymal stem cells derived adipocytes will increase amazingly,but the osteoblasts will be decreased obviously.In the meantime,the activity of the osteoclasts will be activated.So,these mechanisms work together and lead to ONFH.展开更多
The Helegangnaren feldspar granite exposed in the eastern part of East Kunlun, is characterized by high concentrations of SiO2 and alkaline, low abundances of Fe, Mg and Ca, metaluminous-weak peraluminous. Trace eleme...The Helegangnaren feldspar granite exposed in the eastern part of East Kunlun, is characterized by high concentrations of SiO2 and alkaline, low abundances of Fe, Mg and Ca, metaluminous-weak peraluminous. Trace elements analysis shows that the granite is depleted extremely in Ba, Sr and Eu, and rich in some large-ion lithophile elements and high field strength elements. Besides, the granite has high Ga contents, the values of 104（Ga/AI） vary from 2.50 to 2.77, which is mainly greater than the lower limit of A-type granites （2.6）, and is higher than the I- and S- type granites＇ average （2.1 and 2.28, respectively）. Rare earth element （REE） is characterized by relatively high fractionations of light REE （LREE） and heavy REE （HREE） （LREE/HREE=9.3-13.60, （La/Yb）N=10.92-18.02）, pronounced negative Eu anomalies （JEn=0.08-0.13）, and exhibits right- dipping gull pattern. Major elements, rare elements and trace elements features show the granite is ascribed to A-type granite and A2 subtype in tectonic genetic type. They are plotted into post-collision or within-plate area in a variety of tectonic discriminations. Geological and geochemical data comprehensively suggest that the granite is formed in a post-collision extensive tectonic setting. Laser ablation inductively coupled plasma mass spectrometry （LA-ICP-MS） zircon U-Pb dating yields a weighted mean age of 425 Ma, belonging to Middle Silurian, which is similar to the age of the post- collision geological events in the region. The differences of magmatic rocks in formation age, rocks assemblage and rocks series systematically indicate that the regional tectonic stress regime in the East Kunlun orogenic belt experienced a major transformation from compress to extension in Middle Silurianin, and the Helegangnaren feldspar granite intruded in the early stage of tectonic transformation.展开更多
As a revolutionary industrial technology,additive manufacturing creates objects by adding materials layer by layer and hence can fabricate customized components with an unprecedented degree of freedom.For metallic mat...As a revolutionary industrial technology,additive manufacturing creates objects by adding materials layer by layer and hence can fabricate customized components with an unprecedented degree of freedom.For metallic materials,unique hierarchical microstructures are constructed during additive manufacturing,which endow them with numerous excellent properties.To take full advantage of additive manufacturing,an in-depth understanding of the microstructure evolution mechanism is required.To this end,this review explores the fundamental procedures of additive manufacturing,that is,the formation and binding of melt pools.A comprehensive processing map is proposed that integrates melt pool energy-and geometry-related process parameters together.Based on it,additively manufactured microstructures are developed during and after the solidification of constituent melt pool.The solidification structures are composed of primary columnar grains and fine secondary phases that form along the grain boundaries.The post-solidification structures include submicron scale dislocation cells stemming from internal residual stress and nanoscale precipitates induced by intrinsic heat treatment during cyclic heating of adjacent melt pool.Based on solidification and dislocation theories,the formation mechanisms of the multistage microstructures are thoroughly analyzed,and accordingly,multistage control methods are proposed.In addition,the underlying atomic scale structural features are briefly discussed.Furthermore,microstructure design for additive manufacturing through adjustment of process parameters and alloy composition is addressed to fulfill the great potential of the technique.This review not only builds a solid microstructural framework for metallic materials produced by additive manufacturing but also provides a promising guideline to adjust their mechanical properties.展开更多
Various active components have been extracted from the root of Polygonum cuspidatum. However, the genetic basis for their activity is virtually unknown. In this study, 25600002 short reads （2.3 Gb） of P. cuspidatum ...Various active components have been extracted from the root of Polygonum cuspidatum. However, the genetic basis for their activity is virtually unknown. In this study, 25600002 short reads （2.3 Gb） of P. cuspidatum root transcriptome were obtained via lllumina HiSeq 2000 sequencing. A total of 86418 urtigenes were assembled de novo and annotated. Twelve, 18, 60 and 54 unigenes were respectively mapped to the mevalonic acid （MVA）, methyl-D-erythritol 4-phosphate （MEP）, shikimate and resveratrol biosynthesis pathways, suggesting that they are involved in the biosynthesis of pharmaceutically important anthra- quinone and resveratrol. Eighteen potential UDP-glycosyltransferase unigenes were identified as the candidates most likely to be involved in the biosynthesis of glycosides of secondary metabolites. Identification of relevant genes could be important in eventually increasing the yields of the medicinally useful constituents of the P. cuspidatum root. From the previously published transcriptome data of 19 non-model plant taxa, 1127 shared orthologs were identified and characterized. This information will be very useful for future functional, phylogenetic and evolutionary studies of these plants.展开更多
基金This work was supported in part by grants from the National Science and Technology Major Projects for“Major New Drugs Innovation and Development”(directed by Dr.Song Li)(2018ZX09711003)of Chinathe National Key R&D Program(2018YFC0310600)of China+1 种基金the National Natural Science Foundation of China(31771412)Special Fund for strategic bio-resources from Chinese Academy of Sciences(ZSYS-014).
文摘Dear Editor,The occurrence of concentrated pneumonia cases in Wuhan city,Hubei province of China was first reported on December 30,2019 by the Wuhan Municipal Health Commission(WHO,2020).The pneumonia cases were found to be linked to a large seafood and animal market in Wuhan,and measures for sanitation and disinfection were taken swiftly by the local government agency.The Centers for Disease Control and Prevention(CDC)and Chinese health authorities later determined and announced that a novel coronavirus(CoV),denoted as 2019-nCoV,had caused the pneumonia outbreak in Wuhan city(CDC,2020).Scientists from multiple groups had obtained the virus samples from hospitalized patients(Normile,2020).The isolated viruses were morphologically identical when observed under electron microscopy.
基金Supported by the National Natural Science Foundation of China,No.81300251
文摘Liver fibrosis is a reversible wound-healing process aimed at maintaining organ integrity, and presents as the critical pre-stage of liver cirrhosis, which will eventually progress to hepatocellular carcinoma in the absence of liver transplantation. Fibrosis generally results from chronic hepatic injury caused by various factors, mainly viral infection, schistosomiasis, and alcoholism; however, the exact pathological mechanisms are still unknown. Although numerous drugs have been shown to have antifibrotic activity in vitro and in animal models, none of these drugs have been shown to be efficacious in the clinic. Importantly, hepatic stellate cells(HSCs) play a key role in the initiation, progression, and regression of liver fibrosis by secreting fibrogenic factors that encourage portal fibrocytes, fibroblasts, and bone marrow-derived myofibroblasts to produce collagen and thereby propagate fibrosis. These cells are subject to intricate cross-talk with adjacent cells, resulting in scarring and subsequent liver damage. Thus, an understanding of the molecular mechanisms of liver fibrosis and their relationships with HSCs is essential for the discovery of new therapeutic targets. This comprehensive review outlines the role of HSCs in liver fibrosis and details novel strategies to suppress HSC activity, thereby providing new insights into potential treatments for liver fibrosis.
基金Supported by the National Oil-Gas Special Project (Grant No. XQ-2004-07)SinoPetrol & Chemical Corporation (Grant No. P04031)the Key Laboratory of Continental Dynamics, Northwest University
文摘Zircon LA-ICP MS U-Pb dating of six metamorphic rocks and a metagranite (breccia) from southern basement of the Songliao Basin are reported in order to constrain the formation ages of basement. The basement metamorphic rocks in the Songliao Basin mainly consist of metagabbro (L45-1), amphibolite (SN117), metarhyolitical tuff (G190), sericite (Ser) schist (N103), chlorite (Chl) schist (T5-1), biotite (Bi)-actinolite (Act)-quartz (Q) schist (Y205), and metagranite (L44-1). The cathodoluminesence (CL) images of the zircons from metagabbro (L45-1) and metagranite (L44-1) indicate that they have cores of magmatic origin and rims of metamorphic overgrowths. Their U-Pb isotopic ages are 1808±21 Ma and 1873±13 Ma, respectively. The zircons with oscillatory zoning from amphibolite (SN117) and Chl schist (T5-1), being similar to those of mafic igneous rocks, yield ages of 274 ± 3.4 Ma and 264 ± 3.2 Ma, re-spectively. The zircons from metarhyolitical tuff (G190) and Ser schist (N103) display typical magmatic growth zoning and yield ages of 424 ± 4.5 Ma and 287 ± 5.1Ma, respectively. Most of zircons from Bi-Act-Q schist (Y205) are round in shape and different in absorption degree in the CL images, implying their sedimentary detritals. U-Pb dating yield concordant ages of 427 ± 3.1Ma, 455 ± 12 Ma, 696 ± 13 Ma, 1384±62 Ma, 1649±36 Ma, 1778±18 Ma, 2450±9 Ma, 2579±10 Ma, 2793±4 Ma and 2953±14 Ma. The above-mentioned results indicate that the Precambrian crystalline basement (1808―1873 Ma) exists in the southern Songliao Basin and could be related to tectonic thrust, and that the Early Paleozoic (424―490 Ma) and Late Paleozoic magmatisms (264―292 Ma) also occur in the basin basement, which are consistent with the ages of the detrital zircons from Bi-Act-Q schist in the basement.
基金Acknowledgment This research was supported by grants from the Ministry of Science and Technology of China （2006CB943901, 2007CB948003） the National Natural Science Foundation of China （30600306, 30623003） Shanghai Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences （2007KIP 101,2007KIP401）, Chinese Academy of Sciences.
文摘Dear Editor, Human embryonic stem （ES） cells possess the potential to differentiate into all the cell types of the human body and provide potential applications in regenerative medicine . However, the concerns of immune rejection hamper transplantation therapies using human ES cells. To avoid the complications of immune rejection, diverse methods, such as somatic nuclear transfer （also called therapeutic cloning） and fusion of somatic ceils with human ES ceils , have been attempted to produce patient-specific pluripotent stem cells. Most of these approaches have resulted in little success. The generation of human iPS cells （induced
文摘AIM To assess the possible roles of cytokines (TNF α, IFN γ, IL 6 and IL 8) in liver damage of hepatitis B. METHODS The serum TNF α, IFN γ, IL 6 and IL 8 were detected by ELISA in 66 patients with hepatitis B and 20 healthy blood donors. RESULTS TNF α and IL 6 in all types of clinical hepatitis B were significantly higher than those in healthy blood donors ( P <0 05); meanwhile the levels of TNF α, IFN γ, IL 6 and IL 8 in the patients with fulminant hepatitis B were much higher than those in the patients with acute hepatitis B ( P <0 05); the level of TNF α was positively correlated with the levels of IFN γ, Il 6 and IL 8 in all types of hepatitis B ( r IFN =0 24, r IL 6 =0 35, r IL 8 =0 44) and the TNF α, IFN γ, IL 6 and IL 8 were positively correlated with serum bilirubin ( P <0 05). Dynamic changes of these cytokines were observed in the course of acute and fulminant hepatitis. The level of IFN γ peaked in the initial period of acute hepatitis and early stage of hepatic coma in fulminant hepatitis; TNF α, IL 6 and IL 8 increased with exacerbation, and reached a peak when the liver damage was most serious, then decreased when patient conditions were improved. CONCLUSION The increased cytokines were related to the inflammation of liver cells and multiple factors may play certain roles in liver damage.
基金This work was supported by the National Natu-ral Science Foundation of China (Grant Nos. 49732080, 40234041).
文摘The Mianle tectonic zone (Mianle zone), an ancient suture zone in addition to the Shangdan suture in the Qinling-Dabie orogenic belt, marks an important tectonic division geo-logically separating north from south and connecting east with west in China continent. To de-termine present structural geometry and kinematics in the Mianle tectonic zone and to recon-struct the formation and evolution history involving plate subduction and collision in the Qinling-Dabie orogenic belt, through a multidisciplinary study, are significant for exploring the mountain-building orogenesis of the central orogenic system and the entire process of the major Chinese continental amalgamation during the Indosinian.
文摘In our experience patients undergoing circumcision are mostly concerned about pain and penile appearances. We conducted a prospective randomized trial to assess the benefits of a new disposable circumcision suture device （DCSD）. A total of 942 patients were equally divided into three groups （conventional circumcision, Shang ring and disposable suture device group）. Patients in the DCSD group were anesthetized with compound 5% lidocaine cream, the others with a 2% lidocaine penile block. Operation time, intra-operative blood loss, incision healing time, intra-operative and post-operative pain, the penile appearance and overall satisfaction degree were measured. Operation time and intra-operative blood loss were significantly lower in the Shang ring and suture device groups compared to the conventional group （P 〈 0.001）. Intra-operative pain was less in the suture device group compared With the other two groups （P 〈 0.001）; whereas post-operative pain was higher in the conventional group compared to the other two groups （P 〈 0.001）. Patients in the suture device （80.57%） and Shang ring （73,57%） groups were more satisfied with penile appearances compared with the conventional circumcision group （20.06%, P 〈 0.05）. Patients in suture device group also healed markedly faster than the conventional group （P 〈 0.01）. The overall satisfaction rate was better in the suture device group （78.66%） compared with the conventional （47.13%） and Shang ring （50.00%） groups （P 〈 0.05）. The combination of DCSD and lidocaine cream resulted in shorter operation and incision healing times, reduced intra-operative and post-operative pain and improved patient satisfaction with the cosmetic appearances.
基金This study was supported by a grant from National Natural Science Foundation of China(No.30271245)Hi-Tech Research and Development Program of China(863 Program)(No.2003AA205170)+1 种基金National Basic Research Program of China(973 Program)(No.G 1999054302)a grant from Bejing Gynecology and Obstetrics Hospital Affiliate of Capital University of Medical Sciences.
文摘Human placenta-derived mononuclear cells （MNC） were isolated by a Percoll density gradient and cultured in mesenchymal stem cell （MSC） maintenance medium. The homogenous layer of adherent cells exhibited a typical fibroblastlike morphology, a large expansive potential, and cell cycle characteristics including a subset of quiescent cells. In vitro differentiation assays showed the tripotential differentiation capacity of these cells toward adipogenic, osteogenic and chondrogenic lineages. Flow cytometry analyses and immunocytochemistry stain showed that placental MSC was a homogeneous cell population devoid of hematopoietic cells, which uniformly expressed CD29, CD44, CD73, CD105, CD166, laminin, fibronectin and vimentin while being negative for expression of CD31, CD34, CD45 and m-smooth muscle actin. Most importantly, immuno-phenotypic analyses demonstrated that these cells expressed class Ⅰ major histocompatibility complex （MHC-I）, but they did not express MHC-Ⅱ molecules. Additionally these cells could suppress umbilical cord blood （UCB） lymphocytes proliferation induced by cellular or nonspecific mitogenic stimuli. This strongly implies that they may have potential application in allograft transplantation. Since placenta and UCB are homogeneous, the MSC derived from human placenta can be transplanted combined with hematopoietic stem cells （HSC） from UCB to reduce the potential graft-versus-host disease （GVHD） in recipients.
基金the National Natural Science Foundation of China (Grant Nos. 40672038 and 40739905)
文摘LA-ICP-MS zircon U-Pb dating and geochemical data for the Late Paleozoic volcanic rocks from eastern and southeastern margins of the Jiamusi Massif are presented to understand the regional tectonic evolution. Zircons from eight representative volcanic rocks are euhedral-subhedral in shape and dis- play striped absorption and fine-scale oscillatory growth zoning as well as high Th/U ratios (0.33―2.37), implying a magmatic origin. The dating results show that the Late Paleozoic volcanic rocks in the study area can be divided into two stages, i.e., the Early Permian (a weighted mean 206Pb/238U age of 288 Ma) and the Middle Permian volcanisms (a weighted mean 206Pb/238U age of 268 Ma). The former is com- posed mainly of basalt, basaltic-andesite, andesite and minor dacite. They are characterized by low SiO2 contents, high Mg# (0.40―0.59), enrichment in Na (Na2O/K2O = 1.26―4.25) and light rare earth elements (LREEs), relative depletion in heavy rare earth elements (HREEs) and high field strength ele- ments (HFSEs), indicating that an active continental margin setting could exist in the eastern margin of the Jiamusi Massif in the Early Permian. The latter consists mainly of rhyolite and minor dacite with high SiO2 (77.23%―77.52%), low MgO (0.11%―0.14%), enrichment in K2O (Na2O/K2O ratios < 0.80) and Rb, Th, U and depletion in Eu, Sr, P and Ti, implying a crust-derived origin. Therefore, it is proposed that the Middle Permian volcanic rocks could have formed under the collision of the Jiamusi and the Khanka Massifs.
基金supported by the National Key Research and Development Program of China[2016YFC1306300]the National Natural Science Foundation of China[No.81401734]+1 种基金the National Research Foundation for the Doctoral Program of Higher Education of China[No.20121107110001]the National Natural Science Foundation of China[No.81472007]
文摘Objective MicroRNAs （miRs） are attractive molecules to be considered as one of the blood-based biomarkers for neurodegenerative disorders such as Alzheimer＇s disease （AD）. The goal of this study was to explore their potential value as biomarkers for the diagnosis of AD.Methods The expression levels of exosomal miR-135a, -193b, and -384 in the serum from mild cognitive impairment （MCI）, dementia of Alzheimer-type （DAT）, Parkinson＇s disease with dementia （PDD）, and vascular dementia （VaD） patients were measured with a real-time quantitative reverse transcriptase PCR （qRT-PCR） method.Results Both serum exosome miR-135a and miR-384 were up-regulated while miR-193b was down-regulated in serum of AD patients compared with that of normal controls. Exosome miR-384 was the best among the three miRs to discriminate AD, VaD, and PDD. Using the cut-off value could better interpret these laboratory test results than reference intervals in the AD diagnosis. ROC curve showed that the combination of miR-135a, -193b, and -384 was proved to be better than a particular one for early AD diagnosis.Conclusion Our results indicated that the exosomal miRs in the serum were not only potential biomarker of AD early diagnosis, but might also provide novel insights into the screen and prevention of the disease.
基金the National Natural Science Foundation of China, No.39370649
文摘AIM: To evaluate the abnormal immunity and gene mutation at precore 1896 site in patients with severe hepatitis-B.METHODS: This study included 23 patients with severe hepatitis-B, 22 patients with acute hepatitis-B and 20 controls.Mutation at precore 1896 site of HBV gene was confirmed with restriction fragment length polymorphism (RFLP) analysis.Cytokines including TNF-α, IFN-y, IL-6, and IL-8 were measured with ELISA, and T subgroups were detected with alkaline phosphatase anti alkaline phosphatase (APAAP) technique.RESULTS: In patients with severe hepatitis-B, the infective rate of HBV mutant strain was 52.5% (12/23), and only one patient with acute hepatitis-B was infected with the mutant strain. The percentage of CD8+ T lymphocyte was obviously lower (0.16±0.02%) and the ratio of CD4+/CD8+ was obviously higher (2.35±0.89) in mutant group than in wildtype group (0.28±0.05% and 1.31±0.18%, respectively,P＜0.01 or P＜0.05). The levels of cytokines in patients with severe hepatitis-B were higher (TNF-α 359.0±17.2 ng/L, IFNγ 234.7±16.5 ng/L, IL-6 347.5±31.3 ng/L, IL-8 181.1±19.6ng/L) than those in acute hepatitis-B (TNF-α 220.6±8.9ng/L, IFN-γ 174.9±12.0 ng/L, IL-6 285.8±16.5 ng/L, IL-8118.4±5.1 ng/L, P＜0.01 or 0.05). In patients with severe hepatitis-B, the levels of IFN-γ and IL-6 were higher in mutant group (273.4±26.6 ng/L, 387.7±32.5 ng/L) than in wild-type group (207.8±12.8 ng/L, 300.9±16.3 ng/L). The mortality of patients infected with HBV mutant strain was higher (100%)than that with wild-type (0.9%).CONCLUSION: In severe hepatitis-B, the infective rate of HBV mutant strain was high. The mutant strain induces more severe immune disorders in host, resulting in the activation of lymphocyte and release of cytokines. HBV DNA mutates easily in response to the altered immunity. Ultimately liver damage is more prominent.
文摘Objective To review the recent developments in the mechanisms of glucocorticoids induced osteonecrosis of femoral head （ONFH） and introduce a new theory of ONFH.Data sources Both Chinese- and English-language literatures were searched using MEDLINE （1997-2011）,Pubmed （1997-2011 ） and the Index of Chinese-language Literature （1997-2011 ）.Study selection Data from published articles about mechanisms of glucocorticoids induced ONFH in recent domestic and foreign literature were selected.Data extraction Data were mainly extracted from 61 articles which are listed in the reference section of this review.Results Glucocorticoids are steroid hormones secreted by the adrenal cortex that play a pivotal role in the regulation of a variety of developmental,metabolic and immune functions.However,high dose of exogenous glucocorticoids usage is the most common non-traumatic cause of ON FH.Glucocorticoids can affect the metabolisms of osteoblasts,osteoclasts,bone marrow stromal cells and adipocytes which decrease osteoblasts formation but increase adipocytes formation and cause ONFH finally.Conclusions Glucocorticoids affect the differentiation of mesenchymal stem cells,through activating or inhibiting the related transcript regulators of osteogenesis and adipogenesis.At last,the size and volume of mesenchymal stem cells derived adipocytes will increase amazingly,but the osteoblasts will be decreased obviously.In the meantime,the activity of the osteoclasts will be activated.So,these mechanisms work together and lead to ONFH.
基金financially supported by National Natural Science Foundation of China (Grant Nos. 41172186, 40972136 and 40572121)Special Fund for Basic Scientific Research of Central Colleges, Chang’an University, China (Grant Nos.CHD2011TD020, CHD2009JC070, CHD2009JC053 and CHD2009JC046)the Commonweal Geological Survey,the Aluminum Corporation of China and the Land-Resources Department of Qinghai Province (Grant No.200801)
文摘The Helegangnaren feldspar granite exposed in the eastern part of East Kunlun, is characterized by high concentrations of SiO2 and alkaline, low abundances of Fe, Mg and Ca, metaluminous-weak peraluminous. Trace elements analysis shows that the granite is depleted extremely in Ba, Sr and Eu, and rich in some large-ion lithophile elements and high field strength elements. Besides, the granite has high Ga contents, the values of 104（Ga/AI） vary from 2.50 to 2.77, which is mainly greater than the lower limit of A-type granites （2.6）, and is higher than the I- and S- type granites＇ average （2.1 and 2.28, respectively）. Rare earth element （REE） is characterized by relatively high fractionations of light REE （LREE） and heavy REE （HREE） （LREE/HREE=9.3-13.60, （La/Yb）N=10.92-18.02）, pronounced negative Eu anomalies （JEn=0.08-0.13）, and exhibits right- dipping gull pattern. Major elements, rare elements and trace elements features show the granite is ascribed to A-type granite and A2 subtype in tectonic genetic type. They are plotted into post-collision or within-plate area in a variety of tectonic discriminations. Geological and geochemical data comprehensively suggest that the granite is formed in a post-collision extensive tectonic setting. Laser ablation inductively coupled plasma mass spectrometry （LA-ICP-MS） zircon U-Pb dating yields a weighted mean age of 425 Ma, belonging to Middle Silurian, which is similar to the age of the post- collision geological events in the region. The differences of magmatic rocks in formation age, rocks assemblage and rocks series systematically indicate that the regional tectonic stress regime in the East Kunlun orogenic belt experienced a major transformation from compress to extension in Middle Silurianin, and the Helegangnaren feldspar granite intruded in the early stage of tectonic transformation.
基金financial support of National Natural Science Foundation of China(No.51971149)the funding from Science and Technology Innovation Commission of Shenzhen(Nos.KQJSCX20180328095612712,GJHZ20190822095418365)+1 种基金Guangdong Basic and Applied Basic Research Foundation(Nos.2020A1515110869 and 2019A1515110515)Shenzhen-Hong Kong Science and Technology Innovation Cooperation Zone Shenzhen Park Project(No.HZQB-KCZYB-2020030)。
文摘As a revolutionary industrial technology,additive manufacturing creates objects by adding materials layer by layer and hence can fabricate customized components with an unprecedented degree of freedom.For metallic materials,unique hierarchical microstructures are constructed during additive manufacturing,which endow them with numerous excellent properties.To take full advantage of additive manufacturing,an in-depth understanding of the microstructure evolution mechanism is required.To this end,this review explores the fundamental procedures of additive manufacturing,that is,the formation and binding of melt pools.A comprehensive processing map is proposed that integrates melt pool energy-and geometry-related process parameters together.Based on it,additively manufactured microstructures are developed during and after the solidification of constituent melt pool.The solidification structures are composed of primary columnar grains and fine secondary phases that form along the grain boundaries.The post-solidification structures include submicron scale dislocation cells stemming from internal residual stress and nanoscale precipitates induced by intrinsic heat treatment during cyclic heating of adjacent melt pool.Based on solidification and dislocation theories,the formation mechanisms of the multistage microstructures are thoroughly analyzed,and accordingly,multistage control methods are proposed.In addition,the underlying atomic scale structural features are briefly discussed.Furthermore,microstructure design for additive manufacturing through adjustment of process parameters and alloy composition is addressed to fulfill the great potential of the technique.This review not only builds a solid microstructural framework for metallic materials produced by additive manufacturing but also provides a promising guideline to adjust their mechanical properties.
基金supported by the National Science and Technology Major Program (Grant No.2008ZX10005-004)
文摘Various active components have been extracted from the root of Polygonum cuspidatum. However, the genetic basis for their activity is virtually unknown. In this study, 25600002 short reads （2.3 Gb） of P. cuspidatum root transcriptome were obtained via lllumina HiSeq 2000 sequencing. A total of 86418 urtigenes were assembled de novo and annotated. Twelve, 18, 60 and 54 unigenes were respectively mapped to the mevalonic acid （MVA）, methyl-D-erythritol 4-phosphate （MEP）, shikimate and resveratrol biosynthesis pathways, suggesting that they are involved in the biosynthesis of pharmaceutically important anthra- quinone and resveratrol. Eighteen potential UDP-glycosyltransferase unigenes were identified as the candidates most likely to be involved in the biosynthesis of glycosides of secondary metabolites. Identification of relevant genes could be important in eventually increasing the yields of the medicinally useful constituents of the P. cuspidatum root. From the previously published transcriptome data of 19 non-model plant taxa, 1127 shared orthologs were identified and characterized. This information will be very useful for future functional, phylogenetic and evolutionary studies of these plants.
