Unveiling osteoprotective potential of biologically active naringenin in rats with dexamethasone-induced osteoporosis

Objective To investigate the protective effects of naringenin(NRG)against dexamethasone(DEX)-induced osteoporosis(OP)in rats.Methods Molecular docking of NRG was done with AutoDock Vina 1.2.0 software.Forty-eight female Wistar rats were randomly divided into six groups(n=8 each):normal control(NC),DEX(7 mg/kg,i.m.),NRG-low(NRG-L;25 mg/kg,i.g.),NRG-medium(NRG-M;50 mg/kg,i.g.),NRG-high(NRG-H;100 mg/kg,i.g.),and alendronate(ALN;0.25 mg/d,i.g.)groups.OP was induced by administering DEX once a week for five weeks in all groups except NC group.Begining in the third week after the initial DEX administration,the rats in NRG-L,NRG-M,NRG-H,and ALN groups received the corresponding treatments daily for three weeks,while NC and DEX groups received no additional treatment.Serum samples were collected at the end of the experiment for biochemical,bone turnover,antioxidant,lipid profile,and inflammatory cytokine analyses.Femur bones underwent physical parameter testing and histopathological examination.Results The molecular docking results illustrated that NRG docked with calcitonin(CT),lowdensity lipoprotein(LDL),bone morphogenetic protein(BMP),vascular endothelial growth factor(VEGF)receptor,forkhead transcription factors,and osteoprogenitor cells showed good binding energy.In rats administered with 25,50,and 100 mg/kg NRG,there was a significant enhancement in serum biochemical indices,characterized by a reduction in tartrate-resistant acid phosphatase(TRAP),parathyroid hormone(PTH),and an elevation in osteocalcin(OC)and CT levels(P<0.05,P<0.01,and P<0.001,respectively).Despite no significant changes in thickness,weight,and length(P>0.05),there was a marked increase in bone mineral density(BMD)(P<0.01,P<0.001,and P<0.001,respectively).Antioxidant enzyme markers showed significant upregulation,with higher glutathione,superoxide dismutase,and catalase,and a concurrent decrease in malondialdehyde(MDA)(P<0.05,P<0.01,and P<0.001,respectively).The lipid profile also improved significantly,with lower cholesterol(CH),triglycerides(TG),and low-density lipoprotein(LDL)levels,and an increase in high-density lipoprotein(HDL)level(P<0.05,P<0.01,and P<0.001,respectively).Inflammatory cytokine levels were reduced,as evidenced by decreases in tumor necrosis factor(TNF),interleukin(IL)-6,and IL-1β(P<0.05,P<0.01,and P<0.001,respectively).Furthermore,histological alterations revealed obvious improvements,and the body weight of rats treated with NRG showed an increase compared with DEX group.Conclusion These findings imply that NRG exhibited a protective effect against DEX-induced OP in rats as it promotes the bone formation process by increasing the number of bone turnover markers including OC and CT,and restoring of antioxidant status,lipid metabolism,and inflammatory markers.

Physiological Character and Gene Mapping in a New Green-revertible Albino Mutant in Rice

A green-revertible albino mutant-Qiufeng M was found from the japonica rice （Oryza sativa L. ssp. japonica） Qiufeng in the field. The first three leaves of the mutant were albino with some green. The leaf color became pale green since the fourth leaf and the glume had the same phenomenon as the first three leaves. The measuring data of the pigment content confirmed the visually observed results. It truly had a remarkable changing process in the leaf color in Qiufeng M. Comparison of the main agronomic characters between Qiufeng and Qiufeng M indicated that the neck length and grain weight showed significant difference at the 1% level, and other characters were not different. Genetic analysis showed that the green-revertible albino trait was controlled by a single recessive nucleic gene. Using 209 recessive mutant individuals in the F2 population derived from the cross Pei＇ai 64S × Qiufeng M, a gene, tentatively named gra（t）, was located between the SSR markers of RM475 and RM2-22 on the long arm of chromosome 2. The genetic distance were 17.3 cM and 2.9 cM respectively.

Development of RAPD Markers and SCAR Markers Linked to Bentazon Susceptible Lethality Gene in Rice

Rice cultivar Norin 8 and its mutant Norin 8m harbour bentazon resistance trait and bentazon susceptibility trait respectively. A total of 360 arbitrary 10-mer oligonucleotide primers were screened on the genomic DNA of Norin 8 and Norin 8m with RAPD technique. Among which, five primers produced seven polymorphic RAPD bands between Norin 8 and Norin 8m. Amplified RAPD polymorphic products were cloned and sequenced. The sequences were used to design primers for PCR. Five SCAR markers, SCAR/G18/883, SCAR/G18/890, SCAR/G18/919/948, SCAR/D10/1237 and SCAR/F03/1186, were developed from OPG18/943, OPG18/972, OPD10/1248 and OPF03/1198. F-2 progeny of 320 individuals was analyzed to map SCAR markers in relationship to ben or Ben genes. SCAR markers of SCAR/G18/883, SCAR/G18/890, SCAR/G18/919/948 were shown to cosegregate with ben or Ben genes, and SCAR/D10/1237 to be linked of Ben gene with a distance of (14.8 +/- 2.1) cM. The genetic linkage to ben gene and SCAR markers was identified by a pair of near isogenic lines H121 and Hben121. Southern blotting analysis and segregation ratio of F-2 progeny revealed that OPG18/943 and OPG18/972 were single-copy in genome, and locus of OPG18/943 and OPG18/972 were allelic and sequence tagged sites. It is the first report on molecular markers linked to ben or Ben genes. The markers are useful to marker-assisted selection for the breeding and tag ben gene with map-based cloning.

Molecular Tagging and Effect Analysis of a New Small Grain Dwarf Gene in Rice

Plant height is one of the important agronomic traits of rice. Over higher plant would easily result in plant lodging and output reducing. On the other hand, the dwarf varieties with proper plant height had higher lodging resistance and a greater harvest index, allowing for the increased use of nitrogen fertilizer. Dwarf breeding had made a great breakthrough in the rice breeding. The breeding and extension of excellent dwarf varieties remarkably improved the yield potential of rice. Therefore, the plant height is still one of the focuses in rice genetic research.

Screening and Cloning of RAPD Marker of Fluoride Tolerance Gene in Silkworm,Bombyx mori

In this study,silkworm strain T6,tolerant to fluoride,and silkworm strain 733xin,highly sensitive to fluoride,were used to construct the near-isogenic lines.300 random primers were used in RAPD amplification to DNAs of these lines.A molecular marker named S207 was found linked to the fluoride tolerance gene.Examination to F 2 segregated individuals of the above lines verified that this molecular marker was reliable.Subsequently,the molecular marker was cloned into a T vector (pUCm-T) for sequencing.Comparing with sequences available in the GenBank showed that this molecular marker was novel.We plan to convert it into a SCAR marker to facilitate establishment of a molecular marker assisted breeding system.

The Construction of Heat-resistant Near Isogenic Line (NIL) of Bombyx mori and the Development of Molecular Marker Breeding Technique

[Objective] The study aimed to provide theoretical basis for development and application of molecular marker breeding technique to obtain Bombyx mori near-isogenic lines （NILs）. [Method] Thermotolerance gene was introduced into sensitive variety Ou17 by developing NILs and recurrent backcross,then through six generations of backcross,thermotolerance-assisted selection,and two generations of self-cross. [Result] Bombyx mori NILs carrying thermotolerance gene （new germplasm） were produced. Meanwhile,thermotolerance level of progenies of each backcross and molecular markers of NILs were determined,and then attempts were made to produce practical thermotolerance hybrids by using thermotolerance varieties whose thermotolerance gene is linked to SSR markers. [Conclusion] The study successfully construct thermotolerance NILs,monitor thermotolerance level and breeding results of progenies of each backcross,and determine molecular marker of NILs.

Development of Isogenic Lines of Morphological Markers in Indica Rice

A total of 28 accessions of rice (Oryza sativa L.) germplasms were collected from International Rice Research Institute (IRRI), Philippine and Gene Pool of China National Rice Research Institute (CNRRI). These germplasms were attributed as a Donor Gene Pool, consisting of 27 diverse morphological marker lines with each having a unique valuable trait (gene), and the recurrent parent-Zhefu 802, an early-season indica cultivar in south of China in the 1980s and 1990s. A set of 27 isogenic lines with 2-3 markers on every chromosome were obtained after more than 10 successive backcrosses. Moreover, 15 accessions of double-marker isogenic lines were developed by further pyramiding markers on the same chromosome. Key agronomic traits such as heading date, plant height, tillering number and panicle length in this set of lines were similar to that of Zhefu 802 except the marker traits.

ACC Synthase Gene (ACSG) as a Possible Molecular Marker for Female Lines in Cucumber

利用本实验室根据已知序列分离得到的ACC合酶基因 (ACSG)为探针对不同黄瓜 (CucumissativusL .)品种(系 )的基因组DNA进行Southern杂交 ,初步分析了该基因与黄瓜性别表型之间的相关性。发现在所检测的 10个不同品系中 ,ACSG与雌性系表型之间存在明显的相关关系 ,而且这种相关关系在不同的实验中具有良好的重复性。ACSG基因可能是鉴定黄瓜雌性系的一个分子标记。

Improvement of Resistance to Rice Blast in Zhenshan 97 by Molecular Marker-aided Selection

Fungi blast is one of the most serious diseases of rice worldwide. Breeding resistant varieties have been proved to be the most effective and economical means to control the disease. This paper describes the molecular marker-assisted selection (MAS) procedure for a broad-spectrum blast resistant gene Pi1 integrated into an elite hybrid maintainer line, Zhenshan 97. A simple sequence repeat (SSR) based on molecular marker-aided selection system for Pi1 segment was established. Using a backcross population and a blast isolate F1829, Pi1 gene was mapped on the top of chromosome 11 between markers RZ536 and RM144, with a distance of 9.7 cM and 6.8 cM, respectively. Seventeen families derived from the recurrent parent Zhenshan 97 were obtained with homozygous Pi1 gene. The background of the 17 families was identified with inter simple sequence repeat (ISSR) amplification, the highest recovery of the Zhenshan 97 genetic background was 97.01% after the assay of 167 polymorphic bands.

《三遂平妖传》因果复句研究

《三遂平妖传》是元末明初著名的小说家罗贯中所著的一部长篇小说,其中反映了元末明初语言的发展状况。本文着重对《三遂平妖传》中有关系标志的因果复句进行研究,揭示其特点,以进一步了解复句在这一时期的发展状况。

Population Genetic Structure in Apricot (Prunus armeniaca L.) Cultivars Revealed by Fluorescent-AFLP Markers in Southern Xinjiang,China

Population-wide genetic structure was studied using fluorescent-AFLP markers on 85 apricot （Prunus armeniaca L.） cultivars collected from Kuche, Kashi, Hetian in the Tarim Basin, southern Xinjiang Uygur Autonomous Region of China. The purpose of this study was to determine the genetic structure and genotypic diversity among the different eco-geographical populations. Based on the results from this study, 8 pairs of fluorescent-AFLP primers showed clear electrophoregram and high polymorphism amongst the 64 pairs of EcoR Ⅰ/Mse Ⅰ （Mse Ⅰ - a FAM fluorescent marked primer） primers screened. There was a significant polymorphic difference for the same primer pair in different populations and for the same population with different primer pairs. The percentage of polymorphic loci （P） at species level was higher than Kuche, Hetian, Kashi population levels, respectively. The Nei＇s gene diversity index （H） and Shannon＇s information index （I） at species level were higher than those of Kuche, Hetian, and Kashi at population level, respectively. H and I of Kuche population were the highest amongst the three populations. Apricot population genetic diversity was found mainly within the population, Genetic differentiation coefficient between populations （GST） was 0.0882. Gene flow Nm between the populations was 5.1689. Population genetic identity was between 0.9772-0.9811 and genetic distance was between 0.0191-0.0232. These results further indicated that the similarity between populations was higher and the genetic distance between populations was smaller. The UPGMA cluster analysis indicates that the geographical populations at Kuche, Kashi, Hetian were relatively independent Mendelian populations. Concurrently, there was also partial gene exchange between the populations. All the evidences indicated that the genetic diversity in Kuche population was the highest, suggesting that it could be a transition population from wild apricot to cultivated apricot. There were abundant genetic diversities in apricot cultivar populations in southern Xinjiang, China, which provide promising germplasm for further breeding and theoretical basis for biodiversity conservation and utilization for apricot population in this area.

Expression of the Glypican-3 Gene in α-fetoprotein-negative Human Hepatocellular Carcinoma

Objective： To investigate the expression of Glypican-3 gene in （α-fetoprotein （AFP）-negative hepatocellular carcinoma （HCC） and clarify whether Glypican-3 expression is a useful parameter for the diagnosis of hepatocelhllar carcinoma （HCC）, especially for AFP-negative ones. Methods： Forty-one specimens of AFP-negative hepatocellular carcinoma and para-carcimoma tissue were studied for the expression of Glypican-3 by Northern blot. The expression of Glypican-3 protein was detected immunohistochemically with specific polyclonal antibody. Results： Northern blot analysis indicated that the expression of Glypican-3 mRNA was intensively detected in 30 of 41 AFP-negative HCC （73.17%）. In contrast, Glypican-3 mRNA was only weakly detected in 4 of the surrounding non-tumor liver tissues. There was significant difference in the Glypican-3 mRNA expression in large tumors （〉5 cm） （79.31%） and in small tumors （〈5 cm） （41.67%） （P〈0.01）. Gypican-3 mRNA was more frequently overexpressed in poorly differentiated HCC than in well differentiated ones （76.47% vs. 42.86%, P〈0.05）. The Glypican-3 expression was not correlated with age. sex. ttbsAg seropositivity, fibroeapsule, portal venous embolus and intrahepatic metastasis. The overexpression of Glypican-3 protein in HCC was targeted in tumor cells, not in bile duct cells and other interstitial cells. Conclusion： Glypican-3 was specially overexpressed in AFP-negative HCC, and its expression was closely correlated with the tumor size and tumor grade. Glypican-3 gene may play important roles in hepatocareinogenesis, and can be used as a new biochemical marker of HCC, especially for AFP-negative HCC.

Mapping of S-b Locus for F_1 Pollen Sterility in Cultivated Rice Using PCR Based Markers

In cultivated rice ( Oryza sativa L.), F-1 pollen sterility is controlled by at least 6 loci of the F, pollen sterility genes. To map S-b, one of loci, rice variety Taichung 65 (T65) carrying S-b(j)/S-b(j) and its near-isogenic line TIST2 carrying S-b(i)/S-b(i) were used to develop the mapping population. One hundred and fifty-eight microsatellite markers were selected to survey T65 and TISL2. RM13 on chromosome 5 was found to be polymorphic between them. Cosegregation indicated that RM13 was closely linked with locus S-b. Eleven RFLP markers were selected on the corresponding region from the genetic map of Rice Genome Research Program (RGP) of Japan to convert into sequence-tagged site (STS) markers. Amplicon length polymorphism (ALP) was carried out, but none of them was found to be polymorphic between T65 and TISL2. Then PCR-based RFLP (PBR) was done using six 4-nucleotide recognizing restriction endonucleases. Polymorphism was detected when PCR products of R830STS and R2213SSTS were digested with Taq I. Genetic analysis indicated that the distance between locus S-b and markers, R830STS, RM13 and R2213SSTS were 3.3 cM (centi-Morgan), 5.2 cM and 5.5 cM, respectively. These PCR-based markers could be directly used in marker-assisted selection. The technical system combining genetic mapping and PCR-based marker-assisted selection will facilitate the development of molecular breeding.

A Method for Detecting Adhesive Related-Factors of Streptococcus suis Serotype 2 by Real-time PCR

[Objective] This study aimed to establish a method for quantitative detection of mRNA transcriptional level of SS2 adhesive related-factors of Streptococcus suis serotype 2 （SS2） by fluorescent quantitative PCR. []Vlethod] The gene fragments en- coding SS2 adhesive related-factors MRP, FBPS and CPS2J and a housekeeping gene aroA were amplified by reverse transcription PCR from the total RNA of SS2, cloned, and sequenced. The recombinant plasmids containing the target genes were constructed, and used as templates in Real-time PCR. [Result] Dynamic curves, stan- dard curves and melting curves of the adhesive related-factors and aroA were ob- tained by the optimized Real-time PCR system. The standard curves showed a good linear relationship between template copy number and circulation number, and the correlation coefficients （FF） of the standard curves were over 0.995. Also, these as- says were highly specific a^d there was single specific melting peak for every gene. Moreover, the assays were highly sensitive and had a detection limit of 1.0×102 copies in 1 μl of initial templates. Finally, it was highly repeatable and had a coeffi- cient of variation less than 2% for intra-assay. [Conclusion] This study will provide a way to reveal the adhesion mechanism of SS2 to different host cells at molecular level.

Molecular Detection of Healthiness of Bombyx mori

[Objective] The paper was to explore the regularity between heat shock protein expression and the healthiness changes of Bombyx moil materials. [Method] The representative heat shock protein gene Bmhsp24.3 was screened by bioinfor- matic analysis method, and carried out real-time PCR expression analysis. [Result] The target gene Bmhsp24.3 expressed in different B. mori materials, but the expres- sion level in different materials significantly varied. The relative expression level of the gene had different degrees of changes under different rearing conditions. With the increase of rearing temperature, the gene expression was upregulated. The ma- terials with better healthiness had remarkable increase in expression of target gene, while the materials with poorer healthiness had less increase in expression of target gene. The expression difference of target gene Bmhsp24.3 was exactly consistent with the healthiness of breeds. [Conclusion] The healthiness of materials had rela- tionship with expression of target gene Bmhsp24.3. the higher the expression of tar- get gene Bmhsp24.3 was, the better the healthiness of materials was; conversely, the lower the expression of target gene Bmhsp24.3 was, the poorer the healthiness of materials was.

Screening and Application of Molecular Markers for Starch Synthesis-related Genes in Rice

In this study, the genotypes of starch synthesis-related genes were systematically screened from different rice varieties using molecular markers. The results showed that starch synthesis-related genes were highly polymorphic between indica and japonica varieties, as they greatly variated among indica varieties, but were conserved among japonica varieties. The genotypes of two indica varieties9311 and Minghui 63 were more similar to that of japonica varieties. Two or three alleles of six starch synthesis-related genes were found in 28 japonica parental varieties. Four genotypes of two soluble starch synthase genes, SSIIa and SSIIIa,were detected in 88 stable lines derived from the cross of Kanto 194/ Wujing 13 using molecular markers.

Establishment and Application of a Multiplex PCR System for the Detection of Blast Resistance Genes Pi-ta and Pi-b in Rice

Rice blast is one of the important diseases in major rice producing areas of China. The main blast resistance genes Pi-ta and Pi-b showed broad-spectrum and durable resistance to rice blast in many rice growing areas of China, which have been widely utilized in rice breeding and commercial production. In this study, on the basis of detection and verification of the genotypes of 22 rice varieties har- boring known blast resistance genes （Pi-ta and Pi-b） and blast susceptibility genes （pi-ta and pi-b）, two multiple PCR systems for these genes were established by us- ing the functional markers of blast resistance genes Pi-ta and Pi-b as well as blast susceptibility genes pi-ta and pi-b, respectively. Specifically, multiple PCR system I could simultaneously detect blast resistance genes Pi-ta and Pi-b, while system II could detect simultaneously blast susceptibility genes pi-ta and pi-b. In addition, the genotypes of 336 high generation breeding materials were detected with these two multiple PCR systems. The results were highly consistent with those of conventional single mark detection, indicating that these two multiplex PCR systems were stable, reliable and time-saving. The established multiplex PCR systems may serve as a rapid and efficient method to identify and screen rice germplasm resources and can be applied in marker-assisted selection to polymerize multiple genes for blast resis- tance in rice breeding.

Construction of AFLP Molecular Marking System in Mangifera indica L.

[Objective ] The study aimed to construct the AFLP molecular marking system in Mangifera indica. [ Method ] Four varieties of Mangifera indica were used to explore new ways for high-quality DNA, and AFLP analysis of 31 varieties of Mangifera indica was carried out to detect the varietal genetic diversity. [ Result] 14 pairs of primers with stronger polymorphism, better banding patterns and higher resolution were screened out from 64 pairs of selective amplification primers. Then they were used to analyse the fingerprint of 31 varieties of Mangifera indica, the results showed that the ratio of polymorphic bands amplificated by the 14 pairs of primers reached 97% in 31 varieties of Mangifera.[ Conclusion] It was suggested that AFLP was suitable for detecting the polymorphism of Mangifera indica resources.

Molecular Tagging of a New Resistance Gene to Maize Dwarf Mosaic Virus Using Microsatellite Markers

With joint analysis based on the parents, F 1, F 2 and backcrosses, the authors found that the resistance of the maize inbred line Huangzaosi to the maize dwarf mosaic virus strain B was conditioned by a major gene and polygene, and identified a new major gene. Bulked segregate and microsatellite analysis of a F 2 progeny from the combination of Huangzaosi×Mo17 were used to identify the resistance gene, mdm1(t), on the long arm of chromosome 6. This new resistance gene is tightly linked to and located between the microsatellite markers loci, phi077 and bnlg391. The linkage distances between phi077-mdm1(t) and mdm1(t)-bnlg391 are 4.74 centiMorgan (cM) and 6.72 cM respectively.

Research Progress on Mechanized Mixed Sowing Seed Production Technology of Hybrid Rice

Hybrid rice planting has been widely popularized and applied in the world. However, the high cost of seed production and the complicated procedures have become a bottleneck in the development of hybrid rice. The research progress on mixed sowing seed production techniques of hybrid rice was introduced from the aspects of rice resources creation, breeding, sowing seed technology research and cost benefit analysis. The production technology of the new mixed seeding combina- tion ＂Xinhunyou 6＂ was investigated, including the research and validation of benta- zon treatment period and dosage, mixing ratio of male and female parents, and the comparative test of different different sowing methods, which revealed that the mechanization technology of seed production of hybrid rice was mature and feasible and would be one of the most important development trend of technological devel- opment of hybrid rice production.