When an extremely thick rock bed exists above a protected coal seam in the bending zone given the condition of a mining protective seam, this extremely thick rock bed controls the movement of the entire overlying stra...When an extremely thick rock bed exists above a protected coal seam in the bending zone given the condition of a mining protective seam, this extremely thick rock bed controls the movement of the entire overlying stratum. This extremely thick rock bed, called a "main key stratum", will not subside nor break for a long time, causing lower fractures and bed separations not to close and gas can migrate to the bed separation areas along the fractures. These bed separations become gas enrichment areas. By analyzing the rule of fracture evolution and gas migration under the main key stratum after the deep protective coal seam has been mined, we propose a new gas drainage method which uses bore holes, drilled through rock and coal seams at great depths for draining pressure relief gas. In this method, the bores are located at a high level suction roadway (we can also drill them in the drilling field located high in an air gateway). Given the practice in the Haizi mine, the gas drainage rate can reach 73% in the middie coal group, with a gas drainage radius over 100 m.展开更多
Distant hybridization makes it possible to transfer the genome of one species to another, which results in changes in phenotypes and genotypes of the progenies. This study shows that distant hybridization or the combi...Distant hybridization makes it possible to transfer the genome of one species to another, which results in changes in phenotypes and genotypes of the progenies. This study shows that distant hybridization or the combination of this method with gynogenesis or androgenesis lead to different ploidy fishes with genetic variation, including fertile tetraploid hybrids, sterile triploid hybrids, fertile diploid hybrids, fertile diploid gynogenetic fish, and their derived progenies. The formations of the different ploidy fishes depend on the genetic relationship between the parents. In this study, several types of distant hybridization, including red crucian carp (Carassius auratus red var.) (2n=100, abbreviated as RCC) (♀)×common carp (Cyprinus carpio L.) (2n=100, abbreviated as CC) (♂), and RCC (2n=100) (♀)×blunt snout bream (Megalobrama amblycephala) (2n=48, abbreviated as BSB) (♂) are described. In the distant hybridization of RCC (♀)×CC (♂), bisexual fertile F3–F18 allotetraploid hybrids (4n=200, abbreviated as 4nAT) were formed. The diploid hybrid eggs and diploid sperm generated by the females and males of 4nAT developed into diploid gynogenetic hybrids and diploid androgenetic hybrids, respectively, by gynogenesis and androgenesis, without treatment for doubling the chromosome. Improved tetraploid hybrids and improved diploid fishes with genetic variation were derived from the gynogenetic hybrid line. The improved diploid fishes included the high-body RCC and high-body goldfish. The formation of the tetraploid hybrids was related to the occurrence of unreduced gametes generated from the diploid hybrids, which involved in premeiotic endoreduplication, endomitosis, or fusion of germ cells. The sterile triploid hybrids (3n=150) were produced on a large scale by crossing the males of tetraploid hybrids with females of diploid fish (2n=100). In another distant hybridization of RCC (♀)×BSB (♂), different ploidy fishes were obtained, including diploid bisexual fertile natural gynogenetic fish (2n=1展开更多
Wheat is a staple food crop in the world as well as in China. Because of the progress of wheat breeding and other agricultural "sci-technologies, the wheat grain yield per unit area has increased more than five folds...Wheat is a staple food crop in the world as well as in China. Because of the progress of wheat breeding and other agricultural "sci-technologies, the wheat grain yield per unit area has increased more than five folds from 1952 to 2006 in China. The first part of this article briefly reviews the history of wheat breeding in China. Second, the establishment of "Triticum aestivum-Agropyron" distant hybridization system and its contribution to wheat production and breeding in China are summarized. Finally, the future challenges of wheat breeding are discussed, which include how to increase the utilization efficiencies of water, soil nutrient and light energy through breeding. As an example, our research progress on how to increase light use efficiency in wheat through breeding is introduced and discussed.展开更多
The most common malignancy of biliary tract is gallbladder cancer(GBC) which is the third most common cancer in gastrointestinal tract. It is a lethal disease for most patients in spite of growing awareness and improv...The most common malignancy of biliary tract is gallbladder cancer(GBC) which is the third most common cancer in gastrointestinal tract. It is a lethal disease for most patients in spite of growing awareness and improved diagnostic techniques. GBC has a verypoor prognosis and the 5 year survival rate is < 10%. Although etiology of the carcinoma of the gallbladder is still obscure, various factors have been implicated, cholelithiasis being the most frequent. The incidence of GBC worldwide is based on the gender, geography and ethnicity which suggest that both genetic and environmental factors can cause GBC. The major route of spread of gallbladder cancer(GC) is locoregional rather than distant. It spreads by lymphatic, vascular, neural, intraperitoneal, and intraductal routes. Sonography is usually the most common imaging test to evaluate symptoms of biliary tract disease including suspected GC. With recent advances in imaging modalities like multi-detector computed tomography(CT) scanners, magnetic resonance imaging-positron emission tomography/CT diagnosis of gallbladder cancer has improved. Studies have also targeted molecular and genetic pathways. Treatment options have included extended and radical surgeries and adjuvant chemotherapy. This review article deals in detail with important aspects of carcinoma gallbladder and its manifestations and challenges. Role of various imaging modalities in characterization and accurate staging has been discussed. The loco-regional spread of this aggressive malignancy is dealt explicitly.展开更多
AIM: To identify the gastrointestinal stromal tumors(GISTs) that are negative for CD117 expression by immunohistochemistry and to characterize their malignant potential.METHODS: A total of 108 primary mesenchymal tumo...AIM: To identify the gastrointestinal stromal tumors(GISTs) that are negative for CD117 expression by immunohistochemistry and to characterize their malignant potential.METHODS: A total of 108 primary mesenchymal tumors of the gastrointestinal tract were screened to select CD117-negative tumors, from which KIT(exons 9, 11, 13, and 17)and PDGFRA (exons 10, 12, 14, and 18) were sequenced to identify GISTs. Tumor recurrence and distant metastasis were used as the criteria of malignancy.RESULTS: The result showed that approximately 25%(29/108) of the gastrointestinal mesenchymal tumors were negative for CD117 and approximately 6% (7/108)of the tumors were CD117-negative GISTs. All these CD117-negative tumors had a mutated KITand a wildtype PDGFRA. All CD117-negative GISTs with mutations at codons 557/558 of KIThad mitotic counts >10/50 high power field, and 75% (3/4) of them showed multiple recurrence or distant metastasis.CONCLUSION: CD1 17-negative KITmutated GISTs account for approximately 6% of the gastrointestinal mesenchymal tumors. Tumor recurrence or distant metastasis correlates to both theKITmutations at codons 557/558 and the mitotic counts, but not to the tumor size.展开更多
A substantial portion of patients with newly diagnosed gastric cancer has distant metastases(M1 disease).These patients have a very poor prognosis and it is generally accepted that they should be treated with noncurat...A substantial portion of patients with newly diagnosed gastric cancer has distant metastases(M1 disease).These patients have a very poor prognosis and it is generally accepted that they should be treated with noncurative intent. Because it dramatically changes prognosis and treatment plans, it is very important to diagnose distant metastases. In this article, the definition, pathways, incidence and sites of distant metastases in gastric cancer are described.Subsequently, the current performance of imaging in detecting distant metastases in newly diagnosed gastric cancer is outlined and future prospects are discussed.展开更多
Postoperative recurrence occurs in approximately half of patients with non-small cell lung cancer(NSCLC), even after complete resection. Disease recurrence after surgical resection reduces the patient's life expec...Postoperative recurrence occurs in approximately half of patients with non-small cell lung cancer(NSCLC), even after complete resection. Disease recurrence after surgical resection reduces the patient's life expectancy sharply. The prognosis after postoperative recurrence is considered to largely depend on both the mode of first recurrence(distant, locoregional or combined) and the treatment modality:(1) The majority of cases of postoperative recurrence involve distant metastasis with or without locoregional recurrence. Platinum-based systemic chemotherapy is practically accepted as the treatment for these diseases on the basis of evidence for original stage Ⅳ disease. The advent of both pemetrexed and molecular-targeted drugs has improved the survival of nonsquamous NSCLC and changed the chemotherapeutic algorithm for NSCLC;(2) Among patients with distant metastatic recurrence without locoregional recurrence at the primary tumor site, the metastasis is often limited in both organ and number. Such metastases are referred to as oligometastases. Local therapy, such as surgical resection and radiotherapy, has been suggested to be the first-line treatment of choice foroligometastatic recurrence; and(3) While locoregional recurrence is likely to cause troublesome symptoms, it is a potentially limited disease. Therefore, providing local control is important, and radiation is usually beneficial for treating local recurrence. In order to obtain better control of the disease and provide treatment with curative intent in patients with limited disease, the administration of concurrent platinum-based chemoradiotherapy is recommended according to the results of originally nonresectable stage ⅢA and ⅢB disease.展开更多
Lung cancer represents the leading cause of cancer mortality worldwide. Despite improvements in preoperative staging, surgical techniques, neoadjuvant/adjuvant options and postoperative care, there are still major dif...Lung cancer represents the leading cause of cancer mortality worldwide. Despite improvements in preoperative staging, surgical techniques, neoadjuvant/adjuvant options and postoperative care, there are still major difficulties in significantly improving survival, especially in locally advanced non-small cell lung cancer(NSCLC). To date, surgical resection is the primary mode of treatment for stage?Ⅰ?and Ⅱ NSCLC and has become an important component of the multimodality therapy of even more advanced disease with a curative intention. In fact, in NSCLC patients with solitary distant metastases, surgical interventions have been discussed in the last years. Accordingly, this review displays the recent surgical strategies implemented in the therapy of NSCLC patients.展开更多
Stereotactic body radiation therapy(SBRT) is the treatment of choice for medically inoperable patients with early stage non-small cell lung cancer(NSCLC). A literature search primarily based on PubMed electronic datab...Stereotactic body radiation therapy(SBRT) is the treatment of choice for medically inoperable patients with early stage non-small cell lung cancer(NSCLC). A literature search primarily based on PubMed electronic databases was completed in July 2018. Inclusion and exclusion criteria were determined prior to the search, and only prospective clinical trials were included. Nineteen trials from 2005 to 2018 met the inclusion criteria, reporting the outcomes of 1434 patients with central and peripheral early stage NSCLC. Patient eligibility,prescription dose and delivery, and follow up duration varied widely. Threeyears overall survival ranged from 43% to 95% with loco-regional control of up to 98% at 3 years. Up to 33% of patients failed distantly after SBRT at 3 years. SBRT was generally well tolerated with 10%-30% grade 3-4 toxicities and a few treatment-related deaths. No differences in outcomes were observed between conventionally fractionated radiation therapy and SBRT, central and peripheral lung tumors, or inoperable and operable patients. SBRT remains a reasonable treatment option for medically inoperable and select operable patients with early stage NSCLC. SBRT has shown excellent local and regional control with toxicity rates equivalent to surgery. Decreasing fractionation schedules have been consistently shown to be both safe and effective. Distant failure is common, and chemotherapy may be considered for select patients. However, the survival benefit of additional interventions, such as chemotherapy, for early stage NSCLC treated with SBRT remains unclear.展开更多
Distant hybridization refers to crosses between two different species or higher-ranking taxa that enables interspecific genome transfer and leads to changes in phenotypes and genotypes of the resulting progeny.If prog...Distant hybridization refers to crosses between two different species or higher-ranking taxa that enables interspecific genome transfer and leads to changes in phenotypes and genotypes of the resulting progeny.If progeny derived from distant hybridization are bisexual and fertile,they can form a hybrid lineage through self-mating,with major implications for evolutionary biology,genetics,and breeding.Here,we review and summarize the published literature,and present our results on fish distant hybridization.Relevant problems involving distant hybridization between orders,families,subfamilies,genera,and species of animals are introduced and discussed,with an additional focus on fish distant hybrid lineages,genetic variation,patterns,and applications.Our review serves as a useful reference for evolutionary biology research and animal genetic breeding.展开更多
Background: According to the 7 th edition of the American Joint Committee on Cancer(AJCC) staging system, over50% of patients with nasopharyngeal carcinoma(NPC) have N1 disease at initial diagnosis. However, patients ...Background: According to the 7 th edition of the American Joint Committee on Cancer(AJCC) staging system, over50% of patients with nasopharyngeal carcinoma(NPC) have N1 disease at initial diagnosis. However, patients with N1 NPC are relatively under-researched, and the metastasis risk of this group is not well-stratified. This study aimed to evaluate the prognostic values of gross tumor volume of metastatic regional lymph node(GTVnd) and pretreatment serum copy number of Epstein-Barr virus(EBV) DNA in predicting distant metastasis of patients with N1 NPC, and to develop an integrated prognostic model that incorporates GTVnd and EBV DNA copy number for this group of patients.Methods: The medical records of 787 newly diagnosed patients with nonmetastatic, histologically proven N1 NPC who were treated at Sun Yat-sen University Cancer Center between November 2009 and February 2012 were analyzed. Computed tomography-derived GTVnd was measured using the summation-of-area technique. Blood samples were collected before treatment to quantify plasma EBV DNA. The receiver operating characteristic(ROC) curve analysis was used to evaluate the cut-off point for GTVnd, and the area under the ROC curve was used to assess the predicted validity of GTVnd. The survival rates were assessed by Kaplan-Meier analysis, and the survival curves were compared using a log-rank test. Multivariate analysis was conducted using the Cox proportional hazard regression model.Results: The 5-year distant metastasis-free survival(DMFS) rates for patients with GTVnd > 18.9 vs.≤ 18.9 mL were82.2% vs. 93.2%(P < 0.001), and for patients with EBV DNA copy number > 4000 vs. < 4000 copies/mL were 83.5% vs.93.9%(P < 0.001). After adjusting for GTVnd, EBV DNA copy number, and T category in the Cox regression model, both GTVnd > 18.9 mL and EBV DNA copy number > 4000 copies/mL were significantly associated with poor prognosis(both P < 0.05). According to combination of GTVnd and EBV DNA copy number, all patients were divided into low-,moderate-, and high-ris展开更多
AIM: DMA mismatch repair (MMR) is an important mechanism for maintaining fidelity of genomic DNA. Abnormalities in one or more MMR genes are implicated in the development of many cancers. We investigated the role of e...AIM: DMA mismatch repair (MMR) is an important mechanism for maintaining fidelity of genomic DNA. Abnormalities in one or more MMR genes are implicated in the development of many cancers. We investigated the role of expression of MMR genes (hMLH1, hPMS1, hPMS2, GTBP/hMSH6, hMSH2) in hepatocellular carcinogenesis. METHODS: We evaluated the expression level of MMR genes in 33 hepatocellular carcinoma (HCC) cases using the multiplex reverse transcription (RT) PCR assays, as well as in 16 cases of normal adjacent hepatic tissues. β-actin gene was used as an internal control and calibrator for quantification of gene expression. RESULTS: Out of the 33 studied cases, 25 were HCV positive and 30 (90.9%) showed reduced expression in one or more of the studied MMR genes. Reduced expression was found in hMSH2(71.9%), hMLH1 (53.3%), GTBP(51.1%), hPMS2 (33.3%) and hPMS1 (6%). A significant correlation was found between reduced expression of hPMS2(P= 0.0069) and GTBP(P= 0.0034), hPMS2 and non-cirrhosis (P= 0.0197), hMLH1 and high grade. On the other hand, 57.1%, 50%, 20%, 18.8%, and 6% of the normal tissues distant to tumors showed reduced expression of hMSH2, hMLH1, GTBP, hPMS2, and hPMS1 respectively. Multivariate analysis revealed a significant correlation between the expression level of hMSH2(P= 0.008), hMLH1 (P= 0.001) and GTBP (P= 0.032) and HCC, between hPMS2, GTBP and HCV-associated HCC (P<0.001, 0.002). CONCLUSION: Reduced expression of MMR genes seems to play an important role in HCV-associated HCC. hPMS2 is likely involved at an early stage of hepatocarcinogenesis since it was detected in normal adjacent tissues. Reduced expression of hPMS2 provides a growth advantage and stimulates proliferation which encourages malignant transformation in non-cirrhotic HCV-infected patients via acquisition of more genetic damages.展开更多
Polyploids are organisms with three or more complete chromosome sets. Polyploidization is widespread in plants and animals, and is an important mechanism of speciation. Genome sequencing and related molecular systemat...Polyploids are organisms with three or more complete chromosome sets. Polyploidization is widespread in plants and animals, and is an important mechanism of speciation. Genome sequencing and related molecular systematics and bioinformatics studies on plants and animals in recent years support the view that species have been shaped by whole genome duplication during evolution. The stability of polyploids depends on rapid genome recombination and changes in gene expression after formation. The formation of polyploids and subsequent diploidization are important aspects in long-term evolution. Polyploids can be formed in various ways. Among them, hybrid organisms formed by distant hybridization could produce unreduced gametes and thus generate offspring with doubled chromosomes, which is a fast, efficient method of polyploidization. The formation of fertile polyploids not only promoted the interflow of genetic materials among species and enriched the species diversity, but also laid the foundation for polyploidy breeding. The study of polyploids has both important theoretical significance and valuable applications. The production and application of polyploidy breeding have brought remarkable economic and social benefits.展开更多
Background:Promising efficacy and manageable toxicity of docetaxel-based concurrent chemoradiotherapy(CCRT)were reported in head and neck cancer.In addition,the effect of CCRT in combination with cisplatin and/or 5-fl...Background:Promising efficacy and manageable toxicity of docetaxel-based concurrent chemoradiotherapy(CCRT)were reported in head and neck cancer.In addition,the effect of CCRT in combination with cisplatin and/or 5-fluorouracil on both locoregionally advanced and metastatic/recurrent nasopharyngeal carcinoma(NPC)was verified.However,CCRT with docetaxel for locoregionally advanced NPC are not well studied.This study aimed to compare effectiveness and toxicities of CCRT with weekly docetaxel versus tri-weekly cisplatin for locoregionally advanced NPC.Methods:Clinical data of patients with locoregionally advanced NPC newly diagnosed between January 2010 and December 2014 receiving CCRT with either weekly docetaxel(15 mg/m2)or tri-weekly cisplatin(80-100 mg/m2)were reviewed.Propensity score matching at a 1:1 ratio was performed to balance baseline characteristics.Adverse events and survival were compared between the two groups.Results:A total of 962 patients were included as the whole cohort,and 448 patients were matched and were regarded as the matched cohort.The median follow-up duration was 48 months for the whole cohort.The 3-year nodal recurrence-free survival rate was significantly increased for patients treated with docetaxel in both the whole(hazard ratio[HR]=0.37,95%confidence interval[CI]0.19-0.72,P=0.030)and matched cohorts(HR=0.33,95%CI 0.14-0.79,P=0.023).However,no significant differences were observed in overall survival,local recurrence-free survival,and distant metastasis-free survival between the two groups in both cohorts.Significantly higher rates of grade 3 radiodermatitis(6.7%vs.1.8%,P=0.001),mucositis(74.5%vs.37.9%,P<0.001),and leucopenia(2.2%vs.11.6%,P<0.001)were observed in the docetaxel group,but any grade of renal injury(1.8%vs.15.1%,P<0.001),vomiting(18.8%vs.88.3%,P<0.001),and ALT elevation(19.2%vs.31.3%,P=0.027)were more common in the cisplatin group.Conclusions:CCRT with weekly low-dose docetaxel is an effective and tolerable therapeutic regimen for locally advanced NPC.It provides a surv展开更多
Hybridization is widely used. However, for a long time, systematic theories and technologies related to hybridization in fish have been lacking. In this study, through long-term systematic research, we investigated an...Hybridization is widely used. However, for a long time, systematic theories and technologies related to hybridization in fish have been lacking. In this study, through long-term systematic research, we investigated and obtained the main rules regarding inheritance and reproduction related to fish distant hybridization. Furthermore, we established one-step and multistep breeding technologies that were suitable for interspecific hybridization and intraspecific hybridization. Simultaneously, we used these two breeding technologies to produce a batch of diploid fish lineages and tetraploid fish lineages and improved fishes. In addition, we widely discuss the methods, technologies and results of hybridization breeding, referring to the domestic and foreign literature on fish hybridization. We hope that this paper will be beneficial for the research and application of fish hybrid breeding.展开更多
AIM:To investigate the impact of intestinal ischemia/reperfusion(I/R) injury and lymph drainage on distant organs in rats.METHODS:Thirty-two Sprague-Dawley male rats,weighing 280-320 g,were randomly divided into blank...AIM:To investigate the impact of intestinal ischemia/reperfusion(I/R) injury and lymph drainage on distant organs in rats.METHODS:Thirty-two Sprague-Dawley male rats,weighing 280-320 g,were randomly divided into blank,sham,I/R,and ischemia/reperfusion and drainage(I/R + D) groups(n = 8).All rats were subjected to 60 min ischemia by clamping the superior mesenteric artery,followed by 120 min reperfusion.The rats in the I/R + D group received intestinal lymph drainage for 180 min.In the sham group,the abdominal cavity was opened for 180 min,but the rats received no treatment.The blank group served as a normal and untreated control.A chromogenic limulus assay kit was used for quantita-tive detection of serum endotoxin.The serum concentrations of tumor necrosis factor-α(TNF-α),interleukin(IL)-6,IL-1β,soluble cell adhesion molecules(sICAM-1),and high mobility group protein box 1(HMGB1) were determined with an enzyme-linked immunosorbent assay kit.Histological evaluations of the intestine,liver,kidney,and lung were performed by hematoxylin and eosin staining and immunohistochemistry.HMGB1 protein expression was assayed by western blot analysis.RESULTS:The serum levels of endotoxin and HMGB1 in the I/R and I/R + D groups were significantly higher than those in the sham group(endotoxin,I/R and I/R + D vs sham:0.033 ± 0.004 EU/mL,0.024 ± 0.003 EU/mL vs 0.017 ± 0.009 EU/mL,respectively,P < 0.05;HMGB1,I/R and I/R + D vs sham:5.473 ± 0.963 EU/mL,4.906 ± 0.552 EU/mL vs 0.476 ± 0.406 EU/mL,respectively,P < 0.05).In addition,endotoxin and HMGB1 were significantly lower in the I/R + D group compared to the I/R group(P < 0.05).The serum inflammatory factors IL-6,IL-1β,and sICAM-1 in the I/R and I/R + D groups were significantly higher than those in the sham group(IL-6,I/R and I/R + D vs sham:41.773 ± 9.753 pg/mL,19.204 ± 4.136 pg/mL vs 11.566 ± 2.973 pg/mL,respectively,P < 0.05;IL-1β,I/R and I/R + D vs sham:144.646 ± 29.378 pg/mL,65.829 ± 10.888 pg/mL vs 38.178 ± 7.157 pg/mL,respectively,P < 0.05;sICAM-1,I/R and 展开更多
基金Projects 2005CB221503 supported by the National Basic Research Program of China70533050 and 50674089 by the National Natural Science Foundation of China2005BA813B-3-06 by the National Tenth 5-Year Key Scientific and Technological Project
文摘When an extremely thick rock bed exists above a protected coal seam in the bending zone given the condition of a mining protective seam, this extremely thick rock bed controls the movement of the entire overlying stratum. This extremely thick rock bed, called a "main key stratum", will not subside nor break for a long time, causing lower fractures and bed separations not to close and gas can migrate to the bed separation areas along the fractures. These bed separations become gas enrichment areas. By analyzing the rule of fracture evolution and gas migration under the main key stratum after the deep protective coal seam has been mined, we propose a new gas drainage method which uses bore holes, drilled through rock and coal seams at great depths for draining pressure relief gas. In this method, the bores are located at a high level suction roadway (we can also drill them in the drilling field located high in an air gateway). Given the practice in the Haizi mine, the gas drainage rate can reach 73% in the middie coal group, with a gas drainage radius over 100 m.
基金supported by the National Natural Science Fund for Distin-guished Young Scholars (Grant No. 30725028)the National Natural Sci-ence Foundation of China (Grant No. 30930071)+1 种基金the State Key Basic Research and Development Program of China (Grant No. 2007CB109200)the Specially-appointed Professor for Lotus Scholars Program of Hunan Province (Grant No. 080648)
文摘Distant hybridization makes it possible to transfer the genome of one species to another, which results in changes in phenotypes and genotypes of the progenies. This study shows that distant hybridization or the combination of this method with gynogenesis or androgenesis lead to different ploidy fishes with genetic variation, including fertile tetraploid hybrids, sterile triploid hybrids, fertile diploid hybrids, fertile diploid gynogenetic fish, and their derived progenies. The formations of the different ploidy fishes depend on the genetic relationship between the parents. In this study, several types of distant hybridization, including red crucian carp (Carassius auratus red var.) (2n=100, abbreviated as RCC) (♀)×common carp (Cyprinus carpio L.) (2n=100, abbreviated as CC) (♂), and RCC (2n=100) (♀)×blunt snout bream (Megalobrama amblycephala) (2n=48, abbreviated as BSB) (♂) are described. In the distant hybridization of RCC (♀)×CC (♂), bisexual fertile F3–F18 allotetraploid hybrids (4n=200, abbreviated as 4nAT) were formed. The diploid hybrid eggs and diploid sperm generated by the females and males of 4nAT developed into diploid gynogenetic hybrids and diploid androgenetic hybrids, respectively, by gynogenesis and androgenesis, without treatment for doubling the chromosome. Improved tetraploid hybrids and improved diploid fishes with genetic variation were derived from the gynogenetic hybrid line. The improved diploid fishes included the high-body RCC and high-body goldfish. The formation of the tetraploid hybrids was related to the occurrence of unreduced gametes generated from the diploid hybrids, which involved in premeiotic endoreduplication, endomitosis, or fusion of germ cells. The sterile triploid hybrids (3n=150) were produced on a large scale by crossing the males of tetraploid hybrids with females of diploid fish (2n=100). In another distant hybridization of RCC (♀)×BSB (♂), different ploidy fishes were obtained, including diploid bisexual fertile natural gynogenetic fish (2n=1
基金Chinese Academy of Sciences (No. KSCXZ-YW-N-059 and KSCX1-YW-03)the National Natural Science Foundation of China (No. 30330390 and 30521001)the State Key Basic Research and Development Plan of China (No.2005CB 120904
文摘Wheat is a staple food crop in the world as well as in China. Because of the progress of wheat breeding and other agricultural "sci-technologies, the wheat grain yield per unit area has increased more than five folds from 1952 to 2006 in China. The first part of this article briefly reviews the history of wheat breeding in China. Second, the establishment of "Triticum aestivum-Agropyron" distant hybridization system and its contribution to wheat production and breeding in China are summarized. Finally, the future challenges of wheat breeding are discussed, which include how to increase the utilization efficiencies of water, soil nutrient and light energy through breeding. As an example, our research progress on how to increase light use efficiency in wheat through breeding is introduced and discussed.
文摘The most common malignancy of biliary tract is gallbladder cancer(GBC) which is the third most common cancer in gastrointestinal tract. It is a lethal disease for most patients in spite of growing awareness and improved diagnostic techniques. GBC has a verypoor prognosis and the 5 year survival rate is < 10%. Although etiology of the carcinoma of the gallbladder is still obscure, various factors have been implicated, cholelithiasis being the most frequent. The incidence of GBC worldwide is based on the gender, geography and ethnicity which suggest that both genetic and environmental factors can cause GBC. The major route of spread of gallbladder cancer(GC) is locoregional rather than distant. It spreads by lymphatic, vascular, neural, intraperitoneal, and intraductal routes. Sonography is usually the most common imaging test to evaluate symptoms of biliary tract disease including suspected GC. With recent advances in imaging modalities like multi-detector computed tomography(CT) scanners, magnetic resonance imaging-positron emission tomography/CT diagnosis of gallbladder cancer has improved. Studies have also targeted molecular and genetic pathways. Treatment options have included extended and radical surgeries and adjuvant chemotherapy. This review article deals in detail with important aspects of carcinoma gallbladder and its manifestations and challenges. Role of various imaging modalities in characterization and accurate staging has been discussed. The loco-regional spread of this aggressive malignancy is dealt explicitly.
文摘AIM: To identify the gastrointestinal stromal tumors(GISTs) that are negative for CD117 expression by immunohistochemistry and to characterize their malignant potential.METHODS: A total of 108 primary mesenchymal tumors of the gastrointestinal tract were screened to select CD117-negative tumors, from which KIT(exons 9, 11, 13, and 17)and PDGFRA (exons 10, 12, 14, and 18) were sequenced to identify GISTs. Tumor recurrence and distant metastasis were used as the criteria of malignancy.RESULTS: The result showed that approximately 25%(29/108) of the gastrointestinal mesenchymal tumors were negative for CD117 and approximately 6% (7/108)of the tumors were CD117-negative GISTs. All these CD117-negative tumors had a mutated KITand a wildtype PDGFRA. All CD117-negative GISTs with mutations at codons 557/558 of KIThad mitotic counts >10/50 high power field, and 75% (3/4) of them showed multiple recurrence or distant metastasis.CONCLUSION: CD1 17-negative KITmutated GISTs account for approximately 6% of the gastrointestinal mesenchymal tumors. Tumor recurrence or distant metastasis correlates to both theKITmutations at codons 557/558 and the mitotic counts, but not to the tumor size.
文摘A substantial portion of patients with newly diagnosed gastric cancer has distant metastases(M1 disease).These patients have a very poor prognosis and it is generally accepted that they should be treated with noncurative intent. Because it dramatically changes prognosis and treatment plans, it is very important to diagnose distant metastases. In this article, the definition, pathways, incidence and sites of distant metastases in gastric cancer are described.Subsequently, the current performance of imaging in detecting distant metastases in newly diagnosed gastric cancer is outlined and future prospects are discussed.
文摘Postoperative recurrence occurs in approximately half of patients with non-small cell lung cancer(NSCLC), even after complete resection. Disease recurrence after surgical resection reduces the patient's life expectancy sharply. The prognosis after postoperative recurrence is considered to largely depend on both the mode of first recurrence(distant, locoregional or combined) and the treatment modality:(1) The majority of cases of postoperative recurrence involve distant metastasis with or without locoregional recurrence. Platinum-based systemic chemotherapy is practically accepted as the treatment for these diseases on the basis of evidence for original stage Ⅳ disease. The advent of both pemetrexed and molecular-targeted drugs has improved the survival of nonsquamous NSCLC and changed the chemotherapeutic algorithm for NSCLC;(2) Among patients with distant metastatic recurrence without locoregional recurrence at the primary tumor site, the metastasis is often limited in both organ and number. Such metastases are referred to as oligometastases. Local therapy, such as surgical resection and radiotherapy, has been suggested to be the first-line treatment of choice foroligometastatic recurrence; and(3) While locoregional recurrence is likely to cause troublesome symptoms, it is a potentially limited disease. Therefore, providing local control is important, and radiation is usually beneficial for treating local recurrence. In order to obtain better control of the disease and provide treatment with curative intent in patients with limited disease, the administration of concurrent platinum-based chemoradiotherapy is recommended according to the results of originally nonresectable stage ⅢA and ⅢB disease.
文摘Lung cancer represents the leading cause of cancer mortality worldwide. Despite improvements in preoperative staging, surgical techniques, neoadjuvant/adjuvant options and postoperative care, there are still major difficulties in significantly improving survival, especially in locally advanced non-small cell lung cancer(NSCLC). To date, surgical resection is the primary mode of treatment for stage?Ⅰ?and Ⅱ NSCLC and has become an important component of the multimodality therapy of even more advanced disease with a curative intention. In fact, in NSCLC patients with solitary distant metastases, surgical interventions have been discussed in the last years. Accordingly, this review displays the recent surgical strategies implemented in the therapy of NSCLC patients.
文摘Stereotactic body radiation therapy(SBRT) is the treatment of choice for medically inoperable patients with early stage non-small cell lung cancer(NSCLC). A literature search primarily based on PubMed electronic databases was completed in July 2018. Inclusion and exclusion criteria were determined prior to the search, and only prospective clinical trials were included. Nineteen trials from 2005 to 2018 met the inclusion criteria, reporting the outcomes of 1434 patients with central and peripheral early stage NSCLC. Patient eligibility,prescription dose and delivery, and follow up duration varied widely. Threeyears overall survival ranged from 43% to 95% with loco-regional control of up to 98% at 3 years. Up to 33% of patients failed distantly after SBRT at 3 years. SBRT was generally well tolerated with 10%-30% grade 3-4 toxicities and a few treatment-related deaths. No differences in outcomes were observed between conventionally fractionated radiation therapy and SBRT, central and peripheral lung tumors, or inoperable and operable patients. SBRT remains a reasonable treatment option for medically inoperable and select operable patients with early stage NSCLC. SBRT has shown excellent local and regional control with toxicity rates equivalent to surgery. Decreasing fractionation schedules have been consistently shown to be both safe and effective. Distant failure is common, and chemotherapy may be considered for select patients. However, the survival benefit of additional interventions, such as chemotherapy, for early stage NSCLC treated with SBRT remains unclear.
基金supported by the Major International Cooperation Projects of the National Natural Science Foundation of China(31210103918)Training Program of the Major Research Plan of the National Natural Science Foundation of China(91331105)+3 种基金the National Key Basic Research Program of China(2012CB722305)the National High Technology Research and Development Program of China(2011AA100403)the Cooperative Innovation Center of Engineering and New Products for Developmental Biology of Hunan Province(20134486)the Construct Program of the Key Discipline in Hunan Province and China
文摘Distant hybridization refers to crosses between two different species or higher-ranking taxa that enables interspecific genome transfer and leads to changes in phenotypes and genotypes of the resulting progeny.If progeny derived from distant hybridization are bisexual and fertile,they can form a hybrid lineage through self-mating,with major implications for evolutionary biology,genetics,and breeding.Here,we review and summarize the published literature,and present our results on fish distant hybridization.Relevant problems involving distant hybridization between orders,families,subfamilies,genera,and species of animals are introduced and discussed,with an additional focus on fish distant hybrid lineages,genetic variation,patterns,and applications.Our review serves as a useful reference for evolutionary biology research and animal genetic breeding.
基金supported by Grants from the National Natural Science Foundation of China(Nos.81372409,81402532)the Sun Yat-sen University Clinical Research 5010 Program(No.2012011)
文摘Background: According to the 7 th edition of the American Joint Committee on Cancer(AJCC) staging system, over50% of patients with nasopharyngeal carcinoma(NPC) have N1 disease at initial diagnosis. However, patients with N1 NPC are relatively under-researched, and the metastasis risk of this group is not well-stratified. This study aimed to evaluate the prognostic values of gross tumor volume of metastatic regional lymph node(GTVnd) and pretreatment serum copy number of Epstein-Barr virus(EBV) DNA in predicting distant metastasis of patients with N1 NPC, and to develop an integrated prognostic model that incorporates GTVnd and EBV DNA copy number for this group of patients.Methods: The medical records of 787 newly diagnosed patients with nonmetastatic, histologically proven N1 NPC who were treated at Sun Yat-sen University Cancer Center between November 2009 and February 2012 were analyzed. Computed tomography-derived GTVnd was measured using the summation-of-area technique. Blood samples were collected before treatment to quantify plasma EBV DNA. The receiver operating characteristic(ROC) curve analysis was used to evaluate the cut-off point for GTVnd, and the area under the ROC curve was used to assess the predicted validity of GTVnd. The survival rates were assessed by Kaplan-Meier analysis, and the survival curves were compared using a log-rank test. Multivariate analysis was conducted using the Cox proportional hazard regression model.Results: The 5-year distant metastasis-free survival(DMFS) rates for patients with GTVnd > 18.9 vs.≤ 18.9 mL were82.2% vs. 93.2%(P < 0.001), and for patients with EBV DNA copy number > 4000 vs. < 4000 copies/mL were 83.5% vs.93.9%(P < 0.001). After adjusting for GTVnd, EBV DNA copy number, and T category in the Cox regression model, both GTVnd > 18.9 mL and EBV DNA copy number > 4000 copies/mL were significantly associated with poor prognosis(both P < 0.05). According to combination of GTVnd and EBV DNA copy number, all patients were divided into low-,moderate-, and high-ris
文摘AIM: DMA mismatch repair (MMR) is an important mechanism for maintaining fidelity of genomic DNA. Abnormalities in one or more MMR genes are implicated in the development of many cancers. We investigated the role of expression of MMR genes (hMLH1, hPMS1, hPMS2, GTBP/hMSH6, hMSH2) in hepatocellular carcinogenesis. METHODS: We evaluated the expression level of MMR genes in 33 hepatocellular carcinoma (HCC) cases using the multiplex reverse transcription (RT) PCR assays, as well as in 16 cases of normal adjacent hepatic tissues. β-actin gene was used as an internal control and calibrator for quantification of gene expression. RESULTS: Out of the 33 studied cases, 25 were HCV positive and 30 (90.9%) showed reduced expression in one or more of the studied MMR genes. Reduced expression was found in hMSH2(71.9%), hMLH1 (53.3%), GTBP(51.1%), hPMS2 (33.3%) and hPMS1 (6%). A significant correlation was found between reduced expression of hPMS2(P= 0.0069) and GTBP(P= 0.0034), hPMS2 and non-cirrhosis (P= 0.0197), hMLH1 and high grade. On the other hand, 57.1%, 50%, 20%, 18.8%, and 6% of the normal tissues distant to tumors showed reduced expression of hMSH2, hMLH1, GTBP, hPMS2, and hPMS1 respectively. Multivariate analysis revealed a significant correlation between the expression level of hMSH2(P= 0.008), hMLH1 (P= 0.001) and GTBP (P= 0.032) and HCC, between hPMS2, GTBP and HCV-associated HCC (P<0.001, 0.002). CONCLUSION: Reduced expression of MMR genes seems to play an important role in HCV-associated HCC. hPMS2 is likely involved at an early stage of hepatocarcinogenesis since it was detected in normal adjacent tissues. Reduced expression of hPMS2 provides a growth advantage and stimulates proliferation which encourages malignant transformation in non-cirrhotic HCV-infected patients via acquisition of more genetic damages.
基金supported by the National High Technology Research and Development Program of China (Grant No. 2011AA100403)the National Natural Science Foundation of China (Grant No. 30930071)+2 种基金the National Special Fund for Scientific Research in Public Benefits (Grant No. 200903046)the Specially-appointed Professor for Lotus Scholars Program of Hunan Province (Grant No. 080648)the Doctoral Fund Priority Development Area (Grant No. 20114306130001)
文摘Polyploids are organisms with three or more complete chromosome sets. Polyploidization is widespread in plants and animals, and is an important mechanism of speciation. Genome sequencing and related molecular systematics and bioinformatics studies on plants and animals in recent years support the view that species have been shaped by whole genome duplication during evolution. The stability of polyploids depends on rapid genome recombination and changes in gene expression after formation. The formation of polyploids and subsequent diploidization are important aspects in long-term evolution. Polyploids can be formed in various ways. Among them, hybrid organisms formed by distant hybridization could produce unreduced gametes and thus generate offspring with doubled chromosomes, which is a fast, efficient method of polyploidization. The formation of fertile polyploids not only promoted the interflow of genetic materials among species and enriched the species diversity, but also laid the foundation for polyploidy breeding. The study of polyploids has both important theoretical significance and valuable applications. The production and application of polyploidy breeding have brought remarkable economic and social benefits.
文摘Background:Promising efficacy and manageable toxicity of docetaxel-based concurrent chemoradiotherapy(CCRT)were reported in head and neck cancer.In addition,the effect of CCRT in combination with cisplatin and/or 5-fluorouracil on both locoregionally advanced and metastatic/recurrent nasopharyngeal carcinoma(NPC)was verified.However,CCRT with docetaxel for locoregionally advanced NPC are not well studied.This study aimed to compare effectiveness and toxicities of CCRT with weekly docetaxel versus tri-weekly cisplatin for locoregionally advanced NPC.Methods:Clinical data of patients with locoregionally advanced NPC newly diagnosed between January 2010 and December 2014 receiving CCRT with either weekly docetaxel(15 mg/m2)or tri-weekly cisplatin(80-100 mg/m2)were reviewed.Propensity score matching at a 1:1 ratio was performed to balance baseline characteristics.Adverse events and survival were compared between the two groups.Results:A total of 962 patients were included as the whole cohort,and 448 patients were matched and were regarded as the matched cohort.The median follow-up duration was 48 months for the whole cohort.The 3-year nodal recurrence-free survival rate was significantly increased for patients treated with docetaxel in both the whole(hazard ratio[HR]=0.37,95%confidence interval[CI]0.19-0.72,P=0.030)and matched cohorts(HR=0.33,95%CI 0.14-0.79,P=0.023).However,no significant differences were observed in overall survival,local recurrence-free survival,and distant metastasis-free survival between the two groups in both cohorts.Significantly higher rates of grade 3 radiodermatitis(6.7%vs.1.8%,P=0.001),mucositis(74.5%vs.37.9%,P<0.001),and leucopenia(2.2%vs.11.6%,P<0.001)were observed in the docetaxel group,but any grade of renal injury(1.8%vs.15.1%,P<0.001),vomiting(18.8%vs.88.3%,P<0.001),and ALT elevation(19.2%vs.31.3%,P=0.027)were more common in the cisplatin group.Conclusions:CCRT with weekly low-dose docetaxel is an effective and tolerable therapeutic regimen for locally advanced NPC.It provides a surv
基金supported by the National Natural Science Foundation of China (31730098, 31430088, and 31802287)the Earmarked Fund for China Agriculture Research System (CARS-45)+2 种基金the Key Research and Development Program of Hunan Province (2018NK2072)Hunan Provincial Natural Science and Technology Major Project (2017NK1031)the Cooperative Innovation Center of Engineering and New Products for Developmental Biology of Hunan Province (20134486)
文摘Hybridization is widely used. However, for a long time, systematic theories and technologies related to hybridization in fish have been lacking. In this study, through long-term systematic research, we investigated and obtained the main rules regarding inheritance and reproduction related to fish distant hybridization. Furthermore, we established one-step and multistep breeding technologies that were suitable for interspecific hybridization and intraspecific hybridization. Simultaneously, we used these two breeding technologies to produce a batch of diploid fish lineages and tetraploid fish lineages and improved fishes. In addition, we widely discuss the methods, technologies and results of hybridization breeding, referring to the domestic and foreign literature on fish hybridization. We hope that this paper will be beneficial for the research and application of fish hybrid breeding.
基金Supported by The National Natural Science Foundation of China,No. 30940069the Natural Sciences Foundation of Beijing,No. 7102127
文摘AIM:To investigate the impact of intestinal ischemia/reperfusion(I/R) injury and lymph drainage on distant organs in rats.METHODS:Thirty-two Sprague-Dawley male rats,weighing 280-320 g,were randomly divided into blank,sham,I/R,and ischemia/reperfusion and drainage(I/R + D) groups(n = 8).All rats were subjected to 60 min ischemia by clamping the superior mesenteric artery,followed by 120 min reperfusion.The rats in the I/R + D group received intestinal lymph drainage for 180 min.In the sham group,the abdominal cavity was opened for 180 min,but the rats received no treatment.The blank group served as a normal and untreated control.A chromogenic limulus assay kit was used for quantita-tive detection of serum endotoxin.The serum concentrations of tumor necrosis factor-α(TNF-α),interleukin(IL)-6,IL-1β,soluble cell adhesion molecules(sICAM-1),and high mobility group protein box 1(HMGB1) were determined with an enzyme-linked immunosorbent assay kit.Histological evaluations of the intestine,liver,kidney,and lung were performed by hematoxylin and eosin staining and immunohistochemistry.HMGB1 protein expression was assayed by western blot analysis.RESULTS:The serum levels of endotoxin and HMGB1 in the I/R and I/R + D groups were significantly higher than those in the sham group(endotoxin,I/R and I/R + D vs sham:0.033 ± 0.004 EU/mL,0.024 ± 0.003 EU/mL vs 0.017 ± 0.009 EU/mL,respectively,P < 0.05;HMGB1,I/R and I/R + D vs sham:5.473 ± 0.963 EU/mL,4.906 ± 0.552 EU/mL vs 0.476 ± 0.406 EU/mL,respectively,P < 0.05).In addition,endotoxin and HMGB1 were significantly lower in the I/R + D group compared to the I/R group(P < 0.05).The serum inflammatory factors IL-6,IL-1β,and sICAM-1 in the I/R and I/R + D groups were significantly higher than those in the sham group(IL-6,I/R and I/R + D vs sham:41.773 ± 9.753 pg/mL,19.204 ± 4.136 pg/mL vs 11.566 ± 2.973 pg/mL,respectively,P < 0.05;IL-1β,I/R and I/R + D vs sham:144.646 ± 29.378 pg/mL,65.829 ± 10.888 pg/mL vs 38.178 ± 7.157 pg/mL,respectively,P < 0.05;sICAM-1,I/R and