Objective To study the effects of cadmium on hepatocellular DNA damage, expression of proto-oncogenes c-myc, c-fos, and c-jun as well as apoptosis in rats. Methods Cadmium chloride at the doses of 5, 10, and 20 μmol/...Objective To study the effects of cadmium on hepatocellular DNA damage, expression of proto-oncogenes c-myc, c-fos, and c-jun as well as apoptosis in rats. Methods Cadmium chloride at the doses of 5, 10, and 20 μmol/kg was given to rats by i.p. and there were 5 male SD rats in each group. Hepatocellular DNA damage was measured by single cell gel electrophoresis (or comet assay), while expression of proto-oncogenes c-myc, c-fos, and c-jun in rat hepatocytes were measured by Northern dot hybridization. C-Myc, c-Fos, and c-Jun were detected with immuno-histochemical method. Hepatocellular apoptosis was determined by TUNEL (TdT-mediated dUTP Nick End Labelling) and flow cytometry. Results At the doses of 5, 10, and 20 μmol/kg, cadmium chloride induced DNA damage in rat hepatocytes and the rates of comet cells were 50.20%, 88.40%, and 93.80%, respectively. Results also showed an obvious dose-response relationship between the rates of comet cells and the dose of cadmium chloride (r=0.9172, P〈0.01). Cadmium chloride at the doses of 5, 10, and 20 μmol/kg induced expression of proto-oncogenes c-myc, c-fos, and c-jun. The positive brown-yellow signal for c-myc, c-fos, and c-jun was mainly located in the cytoplasm of hepatocytes with immunohistochemical method. TUNEL-positive cells were detected in cadmium-treated rat livers. Apoptotic rates (%) of cadmium-treated liver cells at the doses of 5, 10, and 20 μmol/kg were (17.24 ±2.98), (20.58± 1.35), and (24.06±1.77) respectively, being significantly higher than those in the control. The results also displayed an obvious dose-response relationship between apoptotic rates and the dose of cadmium chloride (r=0.8619, P〈0.05). Conclusion Cadmium at 5-20 μmol/kg can induce hepatocellular DNA damage, expression of proto-oncogenes c-myc, c-fos, and c-jun as well as apoptosis in rats.展开更多
BACKGROUND Ameloblastomas are common benign epithelial odontogenic neoplasms that present an aggressive and unpredictable behavior that may modify treatment strategies.Different signaling pathways that participate in ...BACKGROUND Ameloblastomas are common benign epithelial odontogenic neoplasms that present an aggressive and unpredictable behavior that may modify treatment strategies.Different signaling pathways that participate in the progression of these tumors have been identified.B-raf proto-oncogene serine/threonine kinase(BRAF)is a protein involved in the behavior of ameloblastomas,and it is related to many cell mechanisms.BRAF gene mutations have been identified in ameloblastomas,of which the BRAF V600E(valine substituted by glutamic acid at amino acid 600)mutation has been the most common and can be present concomitantly with other mutations that may be involved in its behavior.Targeted therapies have been used as an alternative in the case of resistance or contraindications to conventional treatments.AIM To document the presence of BRAF V600E and additional mutations,their behavior,and targeted therapies in these tumors.METHODS An electronic literature search was conducted according to PRISMA guidelines in PubMed/MEDLINE,Cochrane,EMBASE,and SpringerLink using the terms“ameloblastomas”,“BRAF V600E”,“additional mutations”,and“targeted therapies”.Ameloblastomas were classified according to WHO guidelines.Inclusion criteria were articles in English,published not more than 10 years ago,and studies with laboratory works related to BRAF V600E.Articles were evaluated by two independent reviewers and retrieved for full-text evaluation.The EBLIP Critical Appraisal Checklist was used to evaluate the quality of the eligible studies.Descriptive statistical analysis was performed.RESULTS Two independent reviewers,with a substantial concordance indicated by a kappa coefficient of k=0.76,evaluated a total of 19 articles that were included in this study.The analysis registered 521 conventional ameloblastomas(AM),81 unicystic ameloblastomas(UA),13 ameloblastic carcinomas(AC),three metastatic ameloblastomas(MA),and six peripheral ameloblastomas(PA),of which the histopathological type,anatomic location,laboratory tests,expression of BRAF mutation,and additional mutations were registered.The BRAF V600E mutation was found in 297 AM(57%),63 UA(77.7%),3 AC(23%),1 MA(50%),and 5 PA(83.3%).Follicular type predominated with a total of 116 cases(40%),followed by plexiform type with 63 cases(22.1%).Furthermore,both types presented additional mutations,in which alterations in JAK3 P132T,SMARCB1,PIK3CA,CTNNB1,SMO,and BRAF G606E genes were found.Four case reports were found with targeted therapy to BRAF V600E.CONCLUSION The identification of BRAF V600E and additional mutations as an aid in targeted therapies has been a breakthrough in alternative treatments of ameloblastomas where surgical treatments are contraindicated.展开更多
The western Kunlun orogen in the northwest Tibet Plateau is related to subduction and collision of Proto-and Paleo-Tethys from early Paleozoic to early Mesozoic. This paper presents new LA-ICPMS zircon U-Pb ages and L...The western Kunlun orogen in the northwest Tibet Plateau is related to subduction and collision of Proto-and Paleo-Tethys from early Paleozoic to early Mesozoic. This paper presents new LA-ICPMS zircon U-Pb ages and Lu-Hf isotopes, whole-rock major and trace elements, and Sr–Nd isotopes of two Ordovician granitoid plutons(466–455 Ma) and their Silurian mafic dikes(~436 Ma) in the western Kunlun orogen. These granitoids show peraluminous high-K calcalkaline characteristics, with(^(87)Sr/^(86)Sr)_i value of 0.7129–0.7224, ε_(Nd)(t) values of -9.3 to -7.0 and zircon ε_(Hf)(t) values of -17.3 to -0.2, indicating that they were formed by partial melting of ancient lower-crust(metaigneous rocks mixed with metasedimentary rocks) with some mantle materials in response to subduction of the Proto-Tethyan Ocean and following collision. The Silurian mafic dikes were considered to have been derived from a low degree of partial melting of primary mafic magma. These mafic dikes show initial ^(87)Sr/^(86)Sr ratios of 0.7101–0.7152 and ε_(Nd)(t) values of -3.8 to -3.4 and zircon ε_(Hf)(t) values of -8.8 to -4.9, indicating that they were derived from enriched mantle in response to post-collisional slab break-off. Combined with regional geology, our new data provide valuable insight into late evolution of the Proto-Tethys.展开更多
High-Al chromite from the Kudi chromitites contains a wide range of mineral inclusions. They include clinopyroxene, amphibole, phlogopite, olivine, orthopyroxene, apatite, base-metal sulfides, calcite and brucite. The...High-Al chromite from the Kudi chromitites contains a wide range of mineral inclusions. They include clinopyroxene, amphibole, phlogopite, olivine, orthopyroxene, apatite, base-metal sulfides, calcite and brucite. The modal abundance of inclusions vary greatly among different grains of chromite. The common inclusions are clinopyroxene and amphibole, which occur as monomineral or polymineral associated with other minerals. The shapes of these inclusions tend to follow the growth plane of host chromite. Mineral assemblages and textures demonstrate that some inclusions(olivine, clinopyroxene) are trapped during magmatic stage, and most of the inclusions(e.g., amphibole, phlogopite) are trapped during recrystallization of chromite. Sulfide inclusions are pentlandite, chalcopyrite and cubanite. They occur either as isolated grains or together with silicate minerals, and formed from the separation of sulfide-bearing liquid from silicate magma. The parental magma of chromitites contains Al2O3 15.0wt%–16.5wt%, TiO20.30wt%–1.05wt% based on calculation with the composition of chromite, similar to parental magma of high-Al chromitites from elsewhere and the estimated melt composition is comparable with that of MORB. Considering the high-Mg olivine in disseminated chromitite and abundant hydrous inclusions, we propose that Kudi chromitites formed beneath a volcanic front during the subduction initiation of Proto-Tethys.展开更多
The proto-Philippine Sea Plate(pPSP)has been proposed by several authors to account for the origin of the Mesozoic supra-subduction ophiolites along the Philippine archipelago.In this paper,a comprehensive review of t...The proto-Philippine Sea Plate(pPSP)has been proposed by several authors to account for the origin of the Mesozoic supra-subduction ophiolites along the Philippine archipelago.In this paper,a comprehensive review of the ophiolites in the eastern portion of the Philippines is undertaken.Available data on the geology,ages and geochemical signatures of the oceanic lithospheric fragments in Luzon(Isabela,Lagonoy in Camarines Norte,and Rapu-Rapu island),Central Philippines(Samar,Tacloban,Malitbog and Southeast Bohol),and eastern Mindanao(Dinagat and Pujada)are presented.Characteristics of the Halmahera Ophiolite to the south of the Philippines are also reviewed for comparison.Nearly all of the crust-mantle sequences preserved along the eastern Philippines share Early to Late Cretaceous ages.The geochemical signatures of mantle and crustal sections reflect both mid-oceanic ridge and suprasubduction signatures.Although paleomagnetic information is currently limited to the Samar Ophiolite,results indicate a near-equatorial Mesozoic supra-subduction zone origin.In general,correlation of the crust-mantle sequences along the eastern edge of the Philippines reveal that they likely are fragments of the Mesozoic pPSP.展开更多
Objective To investigate the expressions of estrogen receptor(ER)subtypes and c-met proto-oncogene in human endometrial carcinomas and to assess the clinical significance of ER and c-met in this carcinoma.Methods Reve...Objective To investigate the expressions of estrogen receptor(ER)subtypes and c-met proto-oncogene in human endometrial carcinomas and to assess the clinical significance of ER and c-met in this carcinoma.Methods Reverse transcription PCR(RT-PCR)was used to detect the expressions of ERα,ERβ and c-met proto-oncogene mRNA in 30 samples of endometrial carcinoma and 11 samples of normal endometrium.Results The expression of ERα in endometrial carcinoma(0.70±0.40)was significantly reduced in comparison to that in normal endometrium(1.14±0.56,P<0.05).A similar finding was made for the expression of ERβ in carcinoma(0.24±0.18)versus normal tissues(0.48±0.20,P<0.05).In contrast,c-met mRNA expression was increased in endometrial carcinoma(1.45±0.72)compared to that in normal endometrium(0.42±0.31,P<0.01).A decrease tendency of the expression of ERα was also found from Stage Ⅰ(0.82±0.41)to a more severe Stag Ⅱ-Ⅲ of endometrial carcinoma(0.42±0.17,P<0.05).The analysis of ERα and ERβ mRNA revealed a decrease tendency from shallow to deep invasion of the uterine muscles(P<0.05).We found that the expressions of ERα and ERβ were negatively correlated with c-met proto-oncogene with a coefficient correlation of-0.63(P<0.01)and-0.32(P<0.05),respectively.Conclusion ERα and ERβ are both involved in mutagenic action of carcinogen.C-met proto-oncogene plays an important role in the carcinogenesis and development of endometrial carcinoma.C-met and ER expressions show a negative correlation in the development of endometrial carcinoma.展开更多
The electron capture timescale may be shorter than hydrodynamic timescale in inner iron core of core-collapse supernova according to a recent new idea. Based on the new idea, this paper carries out a numerical simulat...The electron capture timescale may be shorter than hydrodynamic timescale in inner iron core of core-collapse supernova according to a recent new idea. Based on the new idea, this paper carries out a numerical simulation on supernova explosion for the progenitor model Ws15M. The numerical result shows that the size of proto-neutron star has a significant change (decrease about 20%), which may affects the propagation of the shock wave and the final explosion energy.展开更多
AIM: To investigate pathogenic mutations related to malignant pheochromocytoma in neurofibromatosis(NF).METHODS: We present a patient with NF and metastatic pheochromocytoma in whom genetic screening for presence of p...AIM: To investigate pathogenic mutations related to malignant pheochromocytoma in neurofibromatosis(NF).METHODS: We present a patient with NF and metastatic pheochromocytoma in whom genetic screening for presence of pathogenic mutations in RET protooncogene, von Hippel-Lindau(VHL) and succinate dehydrogenase complex subunits B(SDHB) genes were investigated. RET proto-oncogene mutation screening for exons 10, 11, 13, 14, 15, 16 were examined by polymerase chain reaction(PCR) and direct DNA sequencing in patient. Mutation screening for exons 1, 2, 3 of VHL gene was carried out. Both forward and reverse strandswere subjected to direct sequencing after PCR amplification. The entire coding sequence of SDHB gene was screened for the presence of pathogenic mutations by PCR-sequencing.RESULTS: A 45-year-old man presented with abdominal pain and hypertension over the previous year. The patient was a known case of neurofibromatosis type 1(NF1) who presented at the age of 15 years with hyperpigmented and hypopigmented lesions. After complete evaluation for hypertension, biochemical tests and imagings indicated a malignant pheochromocytoma of 120 mm × 70 mm in size. The patient underwent left adrenalectomy, nephrectomy and splenectomy. After surgery the symptoms improved and blood pressure was controlled. After 5 years he was admitted again for evaluation of hypertensive crisis. Biochemical tests were again consistent with pheochromocytoma and disease relapse. Imaging studies and liver biopsy confirmed metastatic pheochromocytoma to the liver and para-aortic area. 131 Iodine-metaiodobenzylguanidine therapy was carried out. Genetic screening of VHL(exons 1, 2, 3), RET proto-oncogene(exons 10, 11, 13, 14, 15, 16) and SDH complex subunits revealed no pathogenic mutation. CONCLUSION: We conclude that mutations in the NF1 gene are responsible for the patient's clinical findings. However, would be helpful to further examine somatic mutations for a more precise study of genotypephenotype correlation.展开更多
Based on Tyler & Evans' principled polysemy and from the perspective of cognition, this research interprets the protoscene of preposition ON and points out that it is defined by means of two aspects: geometric...Based on Tyler & Evans' principled polysemy and from the perspective of cognition, this research interprets the protoscene of preposition ON and points out that it is defined by means of two aspects: geometric and functional, with the former referring to"the TR being in vertical contact with the upper side of the LM"and the latter"the LM supporting it".展开更多
AIM: To investigate the relationship between mutations of rearranged during transfection (RET) proto-oncogene and Chinese patients with Hirschsprung's disease (HD), and to elucidate the genetic mechanism of famili...AIM: To investigate the relationship between mutations of rearranged during transfection (RET) proto-oncogene and Chinese patients with Hirschsprung's disease (HD), and to elucidate the genetic mechanism of familial HD patient at the molecular level.METHODS: Genomic DNA was extracted from venous blood of probands and their relatives in two genealogies.Polymerase chain reaction (PCR) products, which were amplified using specific primers (RET, exons 11, 13, 15and 17), were electrophoresed to analyze the single-strand conformational polymorphism (SSCP) patterns. The positive amplified products were sequenced. Forty-eight sporadic HD patients and 30 normal children were screened for mutations of RET proto-oncogene simultaneously.RESULTS: Three cases with HD in one family were found to have a G heterozygous insertion at nucleotide 18 974 in exon 13 of RET cDNA (18 974insG), which resulted in a frameshift mutation. In another family, a heterozygosity for T to G transition at nucleotide 18 888 in the same exon which resulted in a synonymous mutation of Leu at codon 745 was detected in the proband and his father. Eight RET mutations were confirmed in 48 sporadic HD patients.CONCLUSION: Mutations of RET proto-oncogene may play an important role in the pathogenesis of Chinese patients with HD. Detection of mutated RET proto-oncogene carriers may be used for genetic counseling of potential risk for HD in the affected families.展开更多
Particle induced X-ray Emission(PIXE) was used to analyze the proto-porcelain excavated from Tingziqiao kiln site of Warring States(475–221 BC) in Deqing County of Zhejiang Province, China. It was found that the porc...Particle induced X-ray Emission(PIXE) was used to analyze the proto-porcelain excavated from Tingziqiao kiln site of Warring States(475–221 BC) in Deqing County of Zhejiang Province, China. It was found that the porcelain body and glaze differ from each other in recipes. The porcelain clay of high silicon and low aluminum might be used to make the body of proto-porcelain. Lime and plant or wood ashes might be added into the glaze of the proto-porcelain. Cluster analysis was done to reveal the compositional relationship between the proto-porcelain samples.展开更多
Multiple endocrine neoplasia type 2A(MEN2A)is an autosomal dominant cancer syndrome that is characterized by medullary thyroid carcinoma(MTC),pheochromocytoma(50%-60% of cases),and hyperplasia of the parathyroid gland...Multiple endocrine neoplasia type 2A(MEN2A)is an autosomal dominant cancer syndrome that is characterized by medullary thyroid carcinoma(MTC),pheochromocytoma(50%-60% of cases),and hyperplasia of the parathyroid glands(20%-30% of cases).MEN2A comprises a heterogeneous group of neoplastic disorders that most commonly have a single missense substitution of the Ret proto-oncogene(RET)involving exons 10 and 11.Here,we reported a novel case of MEN2A associated with two variations in two distinct genes,Cys634Gly in RET and a rare Ser73Gly substitution in succinate dehydrogenase,subunit D(SDHD).Because the patient presented with medullary thyroid carcinoma and pheochromocytoma but without parathyroid gland involvement,we speculated that this clinical feature could be correlated with the two substitutions.This is the first report of a MEN2A case involving two different changes one in the RET gene and the other in the SDHD gene.展开更多
This paper presents in a concise way the main characteristics of life from the physical point of view and the most successful theories of biogenesis, together with a mathematical formulation and simulation of proto-bi...This paper presents in a concise way the main characteristics of life from the physical point of view and the most successful theories of biogenesis, together with a mathematical formulation and simulation of proto-biogenesis. We present here a calculation method for biochemical reactions based on the available reaction data base, and using this method, we calculate precise scenarios for the first life cycle, and for the first stages of terrestrial biological evolution.展开更多
少样本学习是目前机器学习研究领域的热点和难点.针对现有的少样本学习模型不能有效捕捉数据特征与数据标签之间的联系,造成分类模型泛化能力弱的问题,提出一种基于元学习的原型空间图卷积网络少样本学习模型FSL-GCNPS(Few-Shot Learnin...少样本学习是目前机器学习研究领域的热点和难点.针对现有的少样本学习模型不能有效捕捉数据特征与数据标签之间的联系,造成分类模型泛化能力弱的问题,提出一种基于元学习的原型空间图卷积网络少样本学习模型FSL-GCNPS(Few-Shot Learning of Graph Convolutional Network on Prototype Space).首先,利用卷积神经网络提取多任务数据的特征向量;其次,为了将特征向量映射到原型空间中,根据元学习的训练策略得到特征向量的类原型表达;然后,通过类原型向量和类向量之间的嵌入表示,构建图结构数据,并进行图卷积网络训练、推理.实验结果表明,相较于经典少样本学习方法,FSL-GCNPS模型拥有更好的分类准确率和分类稳定性.同时,在医学图像领域数据集上实验表明,FSL-GCNPS具有很好的跨域适应性.展开更多
基金This work was supported by the National Natural Science Foundation of China (No. 30271110).
文摘Objective To study the effects of cadmium on hepatocellular DNA damage, expression of proto-oncogenes c-myc, c-fos, and c-jun as well as apoptosis in rats. Methods Cadmium chloride at the doses of 5, 10, and 20 μmol/kg was given to rats by i.p. and there were 5 male SD rats in each group. Hepatocellular DNA damage was measured by single cell gel electrophoresis (or comet assay), while expression of proto-oncogenes c-myc, c-fos, and c-jun in rat hepatocytes were measured by Northern dot hybridization. C-Myc, c-Fos, and c-Jun were detected with immuno-histochemical method. Hepatocellular apoptosis was determined by TUNEL (TdT-mediated dUTP Nick End Labelling) and flow cytometry. Results At the doses of 5, 10, and 20 μmol/kg, cadmium chloride induced DNA damage in rat hepatocytes and the rates of comet cells were 50.20%, 88.40%, and 93.80%, respectively. Results also showed an obvious dose-response relationship between the rates of comet cells and the dose of cadmium chloride (r=0.9172, P〈0.01). Cadmium chloride at the doses of 5, 10, and 20 μmol/kg induced expression of proto-oncogenes c-myc, c-fos, and c-jun. The positive brown-yellow signal for c-myc, c-fos, and c-jun was mainly located in the cytoplasm of hepatocytes with immunohistochemical method. TUNEL-positive cells were detected in cadmium-treated rat livers. Apoptotic rates (%) of cadmium-treated liver cells at the doses of 5, 10, and 20 μmol/kg were (17.24 ±2.98), (20.58± 1.35), and (24.06±1.77) respectively, being significantly higher than those in the control. The results also displayed an obvious dose-response relationship between apoptotic rates and the dose of cadmium chloride (r=0.8619, P〈0.05). Conclusion Cadmium at 5-20 μmol/kg can induce hepatocellular DNA damage, expression of proto-oncogenes c-myc, c-fos, and c-jun as well as apoptosis in rats.
文摘BACKGROUND Ameloblastomas are common benign epithelial odontogenic neoplasms that present an aggressive and unpredictable behavior that may modify treatment strategies.Different signaling pathways that participate in the progression of these tumors have been identified.B-raf proto-oncogene serine/threonine kinase(BRAF)is a protein involved in the behavior of ameloblastomas,and it is related to many cell mechanisms.BRAF gene mutations have been identified in ameloblastomas,of which the BRAF V600E(valine substituted by glutamic acid at amino acid 600)mutation has been the most common and can be present concomitantly with other mutations that may be involved in its behavior.Targeted therapies have been used as an alternative in the case of resistance or contraindications to conventional treatments.AIM To document the presence of BRAF V600E and additional mutations,their behavior,and targeted therapies in these tumors.METHODS An electronic literature search was conducted according to PRISMA guidelines in PubMed/MEDLINE,Cochrane,EMBASE,and SpringerLink using the terms“ameloblastomas”,“BRAF V600E”,“additional mutations”,and“targeted therapies”.Ameloblastomas were classified according to WHO guidelines.Inclusion criteria were articles in English,published not more than 10 years ago,and studies with laboratory works related to BRAF V600E.Articles were evaluated by two independent reviewers and retrieved for full-text evaluation.The EBLIP Critical Appraisal Checklist was used to evaluate the quality of the eligible studies.Descriptive statistical analysis was performed.RESULTS Two independent reviewers,with a substantial concordance indicated by a kappa coefficient of k=0.76,evaluated a total of 19 articles that were included in this study.The analysis registered 521 conventional ameloblastomas(AM),81 unicystic ameloblastomas(UA),13 ameloblastic carcinomas(AC),three metastatic ameloblastomas(MA),and six peripheral ameloblastomas(PA),of which the histopathological type,anatomic location,laboratory tests,expression of BRAF mutation,and additional mutations were registered.The BRAF V600E mutation was found in 297 AM(57%),63 UA(77.7%),3 AC(23%),1 MA(50%),and 5 PA(83.3%).Follicular type predominated with a total of 116 cases(40%),followed by plexiform type with 63 cases(22.1%).Furthermore,both types presented additional mutations,in which alterations in JAK3 P132T,SMARCB1,PIK3CA,CTNNB1,SMO,and BRAF G606E genes were found.Four case reports were found with targeted therapy to BRAF V600E.CONCLUSION The identification of BRAF V600E and additional mutations as an aid in targeted therapies has been a breakthrough in alternative treatments of ameloblastomas where surgical treatments are contraindicated.
基金funded by the Strategic Priority Research Program of Chinese Academy of Sciences,Grant No.XDA20070304the Fundamental Research Funds for the Chinese Academy of Geological Sciences(YYWF201601)+1 种基金projects of China Geological Survey(DD20160004,20160083-1,12120115000801,121201101000150014)the National Natural Science Foundation of China(grant 41772232)
文摘The western Kunlun orogen in the northwest Tibet Plateau is related to subduction and collision of Proto-and Paleo-Tethys from early Paleozoic to early Mesozoic. This paper presents new LA-ICPMS zircon U-Pb ages and Lu-Hf isotopes, whole-rock major and trace elements, and Sr–Nd isotopes of two Ordovician granitoid plutons(466–455 Ma) and their Silurian mafic dikes(~436 Ma) in the western Kunlun orogen. These granitoids show peraluminous high-K calcalkaline characteristics, with(^(87)Sr/^(86)Sr)_i value of 0.7129–0.7224, ε_(Nd)(t) values of -9.3 to -7.0 and zircon ε_(Hf)(t) values of -17.3 to -0.2, indicating that they were formed by partial melting of ancient lower-crust(metaigneous rocks mixed with metasedimentary rocks) with some mantle materials in response to subduction of the Proto-Tethyan Ocean and following collision. The Silurian mafic dikes were considered to have been derived from a low degree of partial melting of primary mafic magma. These mafic dikes show initial ^(87)Sr/^(86)Sr ratios of 0.7101–0.7152 and ε_(Nd)(t) values of -3.8 to -3.4 and zircon ε_(Hf)(t) values of -8.8 to -4.9, indicating that they were derived from enriched mantle in response to post-collisional slab break-off. Combined with regional geology, our new data provide valuable insight into late evolution of the Proto-Tethys.
基金financially supported by grants from the National Natural Science Foundation of China (No.41472051) to J.Wanga grant from the Natural Science and Engineering Research Council of Canada to K.Hattori+1 种基金supported by grants from the China Geological Survey (Nos.1212011121088 12120114044401)
文摘High-Al chromite from the Kudi chromitites contains a wide range of mineral inclusions. They include clinopyroxene, amphibole, phlogopite, olivine, orthopyroxene, apatite, base-metal sulfides, calcite and brucite. The modal abundance of inclusions vary greatly among different grains of chromite. The common inclusions are clinopyroxene and amphibole, which occur as monomineral or polymineral associated with other minerals. The shapes of these inclusions tend to follow the growth plane of host chromite. Mineral assemblages and textures demonstrate that some inclusions(olivine, clinopyroxene) are trapped during magmatic stage, and most of the inclusions(e.g., amphibole, phlogopite) are trapped during recrystallization of chromite. Sulfide inclusions are pentlandite, chalcopyrite and cubanite. They occur either as isolated grains or together with silicate minerals, and formed from the separation of sulfide-bearing liquid from silicate magma. The parental magma of chromitites contains Al2O3 15.0wt%–16.5wt%, TiO20.30wt%–1.05wt% based on calculation with the composition of chromite, similar to parental magma of high-Al chromitites from elsewhere and the estimated melt composition is comparable with that of MORB. Considering the high-Mg olivine in disseminated chromitite and abundant hydrous inclusions, we propose that Kudi chromitites formed beneath a volcanic front during the subduction initiation of Proto-Tethys.
基金Funding support from the Department of Science and Technology,University of the Philippines-Diliman,National Institute of Geological Sciences and National Research Council of the Philippines
文摘The proto-Philippine Sea Plate(pPSP)has been proposed by several authors to account for the origin of the Mesozoic supra-subduction ophiolites along the Philippine archipelago.In this paper,a comprehensive review of the ophiolites in the eastern portion of the Philippines is undertaken.Available data on the geology,ages and geochemical signatures of the oceanic lithospheric fragments in Luzon(Isabela,Lagonoy in Camarines Norte,and Rapu-Rapu island),Central Philippines(Samar,Tacloban,Malitbog and Southeast Bohol),and eastern Mindanao(Dinagat and Pujada)are presented.Characteristics of the Halmahera Ophiolite to the south of the Philippines are also reviewed for comparison.Nearly all of the crust-mantle sequences preserved along the eastern Philippines share Early to Late Cretaceous ages.The geochemical signatures of mantle and crustal sections reflect both mid-oceanic ridge and suprasubduction signatures.Although paleomagnetic information is currently limited to the Samar Ophiolite,results indicate a near-equatorial Mesozoic supra-subduction zone origin.In general,correlation of the crust-mantle sequences along the eastern edge of the Philippines reveal that they likely are fragments of the Mesozoic pPSP.
文摘Objective To investigate the expressions of estrogen receptor(ER)subtypes and c-met proto-oncogene in human endometrial carcinomas and to assess the clinical significance of ER and c-met in this carcinoma.Methods Reverse transcription PCR(RT-PCR)was used to detect the expressions of ERα,ERβ and c-met proto-oncogene mRNA in 30 samples of endometrial carcinoma and 11 samples of normal endometrium.Results The expression of ERα in endometrial carcinoma(0.70±0.40)was significantly reduced in comparison to that in normal endometrium(1.14±0.56,P<0.05).A similar finding was made for the expression of ERβ in carcinoma(0.24±0.18)versus normal tissues(0.48±0.20,P<0.05).In contrast,c-met mRNA expression was increased in endometrial carcinoma(1.45±0.72)compared to that in normal endometrium(0.42±0.31,P<0.01).A decrease tendency of the expression of ERα was also found from Stage Ⅰ(0.82±0.41)to a more severe Stag Ⅱ-Ⅲ of endometrial carcinoma(0.42±0.17,P<0.05).The analysis of ERα and ERβ mRNA revealed a decrease tendency from shallow to deep invasion of the uterine muscles(P<0.05).We found that the expressions of ERα and ERβ were negatively correlated with c-met proto-oncogene with a coefficient correlation of-0.63(P<0.01)and-0.32(P<0.05),respectively.Conclusion ERα and ERβ are both involved in mutagenic action of carcinogen.C-met proto-oncogene plays an important role in the carcinogenesis and development of endometrial carcinoma.C-met and ER expressions show a negative correlation in the development of endometrial carcinoma.
基金Project supported by the National Natural Science Foundation of China(Grant No10778719)the Scientific Research and Fund of Sichuan Provincial Education Department of China(Grant No2006A079)the Science and Technological Foundation of China West Normal University
文摘The electron capture timescale may be shorter than hydrodynamic timescale in inner iron core of core-collapse supernova according to a recent new idea. Based on the new idea, this paper carries out a numerical simulation on supernova explosion for the progenitor model Ws15M. The numerical result shows that the size of proto-neutron star has a significant change (decrease about 20%), which may affects the propagation of the shock wave and the final explosion energy.
文摘AIM: To investigate pathogenic mutations related to malignant pheochromocytoma in neurofibromatosis(NF).METHODS: We present a patient with NF and metastatic pheochromocytoma in whom genetic screening for presence of pathogenic mutations in RET protooncogene, von Hippel-Lindau(VHL) and succinate dehydrogenase complex subunits B(SDHB) genes were investigated. RET proto-oncogene mutation screening for exons 10, 11, 13, 14, 15, 16 were examined by polymerase chain reaction(PCR) and direct DNA sequencing in patient. Mutation screening for exons 1, 2, 3 of VHL gene was carried out. Both forward and reverse strandswere subjected to direct sequencing after PCR amplification. The entire coding sequence of SDHB gene was screened for the presence of pathogenic mutations by PCR-sequencing.RESULTS: A 45-year-old man presented with abdominal pain and hypertension over the previous year. The patient was a known case of neurofibromatosis type 1(NF1) who presented at the age of 15 years with hyperpigmented and hypopigmented lesions. After complete evaluation for hypertension, biochemical tests and imagings indicated a malignant pheochromocytoma of 120 mm × 70 mm in size. The patient underwent left adrenalectomy, nephrectomy and splenectomy. After surgery the symptoms improved and blood pressure was controlled. After 5 years he was admitted again for evaluation of hypertensive crisis. Biochemical tests were again consistent with pheochromocytoma and disease relapse. Imaging studies and liver biopsy confirmed metastatic pheochromocytoma to the liver and para-aortic area. 131 Iodine-metaiodobenzylguanidine therapy was carried out. Genetic screening of VHL(exons 1, 2, 3), RET proto-oncogene(exons 10, 11, 13, 14, 15, 16) and SDH complex subunits revealed no pathogenic mutation. CONCLUSION: We conclude that mutations in the NF1 gene are responsible for the patient's clinical findings. However, would be helpful to further examine somatic mutations for a more precise study of genotypephenotype correlation.
文摘Based on Tyler & Evans' principled polysemy and from the perspective of cognition, this research interprets the protoscene of preposition ON and points out that it is defined by means of two aspects: geometric and functional, with the former referring to"the TR being in vertical contact with the upper side of the LM"and the latter"the LM supporting it".
基金Supported by the Fund for Excellent Young Talented Persons by Public Health Ministry of China, and Analysis and Testing Foundation of Zhejiang Province, No. 99075
文摘AIM: To investigate the relationship between mutations of rearranged during transfection (RET) proto-oncogene and Chinese patients with Hirschsprung's disease (HD), and to elucidate the genetic mechanism of familial HD patient at the molecular level.METHODS: Genomic DNA was extracted from venous blood of probands and their relatives in two genealogies.Polymerase chain reaction (PCR) products, which were amplified using specific primers (RET, exons 11, 13, 15and 17), were electrophoresed to analyze the single-strand conformational polymorphism (SSCP) patterns. The positive amplified products were sequenced. Forty-eight sporadic HD patients and 30 normal children were screened for mutations of RET proto-oncogene simultaneously.RESULTS: Three cases with HD in one family were found to have a G heterozygous insertion at nucleotide 18 974 in exon 13 of RET cDNA (18 974insG), which resulted in a frameshift mutation. In another family, a heterozygosity for T to G transition at nucleotide 18 888 in the same exon which resulted in a synonymous mutation of Leu at codon 745 was detected in the proband and his father. Eight RET mutations were confirmed in 48 sporadic HD patients.CONCLUSION: Mutations of RET proto-oncogene may play an important role in the pathogenesis of Chinese patients with HD. Detection of mutated RET proto-oncogene carriers may be used for genetic counseling of potential risk for HD in the affected families.
基金Supported by the compass special plan from the bureau of cultural relics of China
文摘Particle induced X-ray Emission(PIXE) was used to analyze the proto-porcelain excavated from Tingziqiao kiln site of Warring States(475–221 BC) in Deqing County of Zhejiang Province, China. It was found that the porcelain body and glaze differ from each other in recipes. The porcelain clay of high silicon and low aluminum might be used to make the body of proto-porcelain. Lime and plant or wood ashes might be added into the glaze of the proto-porcelain. Cluster analysis was done to reveal the compositional relationship between the proto-porcelain samples.
基金Supported by National Nature Science Foundation of China(30771018)Shanghai Rising-Star Program,China(08QA14057)
文摘Multiple endocrine neoplasia type 2A(MEN2A)is an autosomal dominant cancer syndrome that is characterized by medullary thyroid carcinoma(MTC),pheochromocytoma(50%-60% of cases),and hyperplasia of the parathyroid glands(20%-30% of cases).MEN2A comprises a heterogeneous group of neoplastic disorders that most commonly have a single missense substitution of the Ret proto-oncogene(RET)involving exons 10 and 11.Here,we reported a novel case of MEN2A associated with two variations in two distinct genes,Cys634Gly in RET and a rare Ser73Gly substitution in succinate dehydrogenase,subunit D(SDHD).Because the patient presented with medullary thyroid carcinoma and pheochromocytoma but without parathyroid gland involvement,we speculated that this clinical feature could be correlated with the two substitutions.This is the first report of a MEN2A case involving two different changes one in the RET gene and the other in the SDHD gene.
文摘This paper presents in a concise way the main characteristics of life from the physical point of view and the most successful theories of biogenesis, together with a mathematical formulation and simulation of proto-biogenesis. We present here a calculation method for biochemical reactions based on the available reaction data base, and using this method, we calculate precise scenarios for the first life cycle, and for the first stages of terrestrial biological evolution.
文摘少样本学习是目前机器学习研究领域的热点和难点.针对现有的少样本学习模型不能有效捕捉数据特征与数据标签之间的联系,造成分类模型泛化能力弱的问题,提出一种基于元学习的原型空间图卷积网络少样本学习模型FSL-GCNPS(Few-Shot Learning of Graph Convolutional Network on Prototype Space).首先,利用卷积神经网络提取多任务数据的特征向量;其次,为了将特征向量映射到原型空间中,根据元学习的训练策略得到特征向量的类原型表达;然后,通过类原型向量和类向量之间的嵌入表示,构建图结构数据,并进行图卷积网络训练、推理.实验结果表明,相较于经典少样本学习方法,FSL-GCNPS模型拥有更好的分类准确率和分类稳定性.同时,在医学图像领域数据集上实验表明,FSL-GCNPS具有很好的跨域适应性.