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Abstract: The genetic diversity of the genus Dendrobium is not well known and the phylogenetic relationship of Dendrobium species are mainly determined by studies of the comparative vegetative anatomy and plant systematics. In the present study, we used the technique of inter-simple sequence repeats (ISSRs) to evaluate genetic diversity and phylogenetic relationship among 31 Dendrobium species from Yunnan region of China. In total, 2368 bands were amplified by 17 ISSR primers, resulting from 278 ISSR loci with 100% polymorphism at genus level. Thirty-one species were unequivocally distinguished based on ISSR fingerprinting. Species-specific ISSR markers were identified in nine of 31 tested Dendrobium species. Unweighted pair-group mean analysis (UPGMA) showed that 31 Dendrobium species were grouped into six clusters, indicating the genus was polyphyletic with several well-supported lineages. The high polymorphism and reliable amplification across species demonstrated the utility of ISSR marker for species diagnosis and genetic diversity study of the genus Dendrobium. [Copyright &y& Elsevier]

Based on the study of the relationships between economic growth and industrial pollutant discharge of Suzhou City in 1991-2005, the environmental Kuznets curve (EKC) of the City was estimated by several kinds of function, with the cause analyzed. The results showed that the EKC of Suzhou was not a typical one. The industrial pollution of the City increased dramatically by scale effect of economic growth and the clear environmental benefit of industrial structure adjustment was not received obviously, while generalized discharge reduction technologies showed great results. In general terms, the pollution increase was comparatively slower than the GDP growth. As a whole, the environmental policy of Suzhou was in effect. However, the relationships between economic growth and industrial pollutant discharge had not been a benign development yet. In order to achieve win-win situation of economic growth and pollution reduction, Suzhou needed to optimize its industry structure, push the energy conservation and discharge reduction policy deeply, increase environmental investment, and enforce the strictest environmental and industrial policy. In doing these, Suzhou could turn the traditional ∩-shaped EKC into Λ-shaped EKC. [ABSTRACT FROM AUTHOR]

Plants use various secondary chemicals in their chemical defense against herbivores. While botanical insecticides are crucial for reducing the reliance on chemical pesticides, the development of plant-derived insecticides remains limited. In this study, we fed Henosepilachna vigintioctopunctata with three different host plants (Solanum nigrum, Solanum tuberosum, and Physalis floridana) and observed that feeding on P. floridana led to changes in the body size and a significantly high mortality rate. Through transcriptome analysis, it was found that the trehalose metabolism pathway of H. vigintioctopunctata changed significantly under different host feeding conditions, especially since the expression level of the trehalase gene was extremely different. We subsequently identified eight transcripts of HvTREs and analyzed their evolution and structure. Among them, significant differences are observed in the relative expression levels of HvTRE1-5 in H. vigintioctopunctata after the fourth instar and were affected by different plant diets. Compared with the natural host S. nigrum, the larvae that fed on P. floridana significantly reduced the contents of trehalose, glucose and glycogen and significantly affected the trehalase activity. Knockdown of HvTRE1-5 by RNAi increased mortality at the H. vigintioctopunctata prepupation stage, suggesting that HvTRE1-5 is important for H. vigintioctopunctata pupation. This study provides new insights into developing of green control methods for H. vigintioctopunctata and offers a valuable example for understanding the interaction between host plants and herbivorous insects. [ABSTRACT FROM AUTHOR]

As traditional Chinese medicinal herbs, Physalis plants have a variety of pharmacological activities, such as anti-inflammatory, anti-oxidant, and anti-cancer effects, and have been used for the treatment of malaria, rheumatism, hepatitis, asthma, and cancer. In addition to the medicinal value, many Physalis species are also the high-grade nutrition health care fruits, can be made canned and candied etc. In the study, the application progress of DNA molecular marker technologies in medicinal Physalis plants in recent years was reviewed, in order to provide an important molecular technical basis for the identification, classification and rational development and protection of medicinal Physalis resources., Competing Interests: The authors of this article and the planning committee members and staff have no relevant financial relationships with commercial interests to disclose., (Copyright© by the Chinese Pharmaceutical Association.)

Objective: To study the mechanisms on drug susceptibility and resistance of clinically multidrug-resistant Escherichia coli isolates, to provide information on related treatment., Methods: The susceptibility of E. coli strains that isolated from different kinds of samples in the last 3 years on drugs was analyzed by agar dilution test, with strains that exhibiting resistances to cefotaxime, ciprofloxacin and amikacin simultaneously collected for further analysis. Resistant genes which mediate resistance to β-lactamases, fluoroquinolone and aminoglycoside as well as phylogenic type were detected by PCR amplification while genetic relation was analyzed by PFGE. Transferability of resistant plasmids was identified by conjugation test., Results: In total, 137 multidrug-resistant E. coli isolates were collected. Only 1% of the isolates exhibited resistance to both imipenem and meropenem while 4% of the strains were resistant to piperacillin/tazobactam. Most (85%) of the isolates were positive to ESBL and majority of them produced CTX-M. Target substitution and production of methylases were the main mechanisms causing resistance to fluoroquinolones and aminoglycosides respectively., Conclusion: The main source of clinical multidrug-resistance was collected from urine samples. Carbapenem and enzyme inhibitor-containing antibiotics seemed to be the available antibiotics that were sensitivity to the clinically multidrug-resistant E. coli isolates.

ISSR was applied to detect the relationship between 16 Cymbidium species, and 836 bands were amplified with 15 primers, including 227 polymorphic bands. The polymorphic percentage is 27.2%. UPGMA results showed that the genetic distance were closest between C.goeringii (Rchb.f.) Rchb.f. and C. goeringii var. longibracteatum, and C.lancifolium Hook. was far away from the other 15 species. This result is quite similar to the traditional classification, indicating that the technique could supplement some information to traditional taxonomy in the molecular level.

Cymbidium is one of the Orchidaceae genera. There are 70 Cymbidium species in the world, mainly distributed over the tropical and the subtropical area of Asia and northern Australia. In China, approximately 49 species and some variations are distributed over the provinces to the south of Qinling. The orchid market of China is quite wide, not only because of their view and admiration value, but also their officinal value as well. Some species of Cymbidium are morphologically similar, so the identification of Cymbidium species and the understanding of the relationships between them are very important for new varieties breeding of Cymbidium. This study attempts to apply RMAPD to detect the relationships between the Cymbidium species. 456 pairs of RMAPD combinations were screened, but only 12 pairs of them were used to analyze the genetic polymorphism of 16 Cymbidium. 362 bands were produced by 12 pairs of RMAPD primers in total, including 90 polymorphic bands (24.8%). The polymorphic bands of each primer combination ranged from 3 to 11 with the average of 8. Among all species, genetic similarity coefficient ranged from 0.63 to 0.87. The result showed that the genetic distance was closest between C. floribundum and C. aestivum, C. ensifolium and C. sinense, C. maguanense and C. hookerianum, which is almost the same as the traditional classification. It was the first time that species of Cymbidium were detected by RMAPD technique. This study shows RMAPD is an appropriate and effective molecular marker technique to identify the relationships of Cymbidium.

The techniques of random amplified polymorphic DNA (RAPD) and amplified fragment length polymorphisms (AFLPs) were used to amplify the genomic DNA of 10 species of Ilex, so as to reveal the polymorphism in different species of Ilex. In RAPD analysis, a total of 301 lines were amplified with 11 kinds of primers selected from 100 kinds of 10 bp random primers, and the polymorphism was 98.63%. In AFLPs analysis,a huge diversity was showed by 3 primers combinations carried out on these species. Both RAPD and AFLPs analysis were clustered by UPGMA and the results showed that the genetic distances were the closest between I. purpurea and I. vomitoria Ait, I. Litseaefolia and I. zhejiangensis, I. hylonoma var. glabra and I. triflora var. kanehirai.

To explore a new approach to generating reproductive sterility in transgenic plants, the barnase gene from Bacillus amyloliquefaciens was placed under the control of an 1853-bp nucleotide sequence from the 3'end of the second intron of Arabidopsis AGAMOUS and CaMV 35S (-60) minimal promoter [AG-I-35S (-60)::Barnase], and was introduced into tobacco through transformation mediated by Agrobacterium tumefaciens. All AG-I-35S (-60)::Barnase transgenic plants showed normal vegetative growth and 28% of the transgenic lines displayed complete ablation of flowering. Two transgenic lines, Bar-5 and Bar-15, were 98.1 and 98.4% sterile, respectively, as determined by seed production and germination. When controlled by AG-I-35S (-60) chimeric promoter, barnase mRNA was detected in the reproductive tissues of transgenic tobacco plants, but not in vegetative parts. This study presents the first application of an AG intron sequence in the engineered ablation of sexual reproduction in plants. The AG-I-35S (-60)::Barnase construct can be useful in diminishing pollen and seed formation in plants, providing a novel bisexual sterility strategy for interception of transgene escape and has other potentially commercial use for transgenic engineering.

Amplified fragment length polymorphism (AFLP) was assessed in 13 Chinese species of Dendrobium. Three primer combinations E+ACT/M+CAC, E+AAC/M+CAC and E+ACA/M+CAC were used for selective amplification. Between 100 bp and 300 bp, a totle of 346 fragments were detected, in which 342 are polymorphic. The rate of polymorphism was 98.8%. The AFLP data were analyzed using Nei & Li similarity coefficient and UPGMA Cluster method. The result indicated that the 13 species were clustered into three groups on coefficient level 0.54. Group I included D. falconeri, D. officinale, D. wilsonii, D. hercoglossum, D. crystallinum. D. hancockii, D. guangxiense, D. primulinum, D. crepidatum, D. thyrsiflorum. Group II included D. chrysotoxum. Group III included D. loddigesii. This outcome was corresponding to the classification result by using the traditional method. It is concluded that AFLP markers can be used on the studies of genetic relationships and classification of Dendrobium.

Filamentous and rod-shaped virions, and aggregated crystals were observed in infected leaves of by negative staining and ultramicrotomy. Histologic study synchronously showed typical crystal forms of the two virions: the crystals from filamentous particles congregated in strips, arrayed in multilayer and piled in certain angles or helix between layers; while the crystals from rod-shaped particles arrayed in parallel, angle-layer or helix. The two kinds of crystals both presented in parenchyma cells, plasmodesma, and vascular bundles; as an evidence that indicates the existence of short distance transport of viruses between cells, plasmodesmata were produced through piercing the membrane around the reproducing viral crystals; the chloroplasts in the infected cells were hypoplastic, and the filamentous virion were observed within the chloroplasts; the mitochondrions were over-developed, swelled or even cavitated; the nucleus were also swelled and cavitated. Further multiplex RT-PCR and sequencing that the coat protein genes simultaneously expanded to Cymbidium mosaic potexvirus (CymMV) and Odontoglossum ringspot tobamovirus (ORSV) showed homology with available abstracts from GenBank, and the respective percentages of identity are 98% and 99%-100%. The instant and direct identification evidences of CymMV and ORSV complex infection on phalaenopsis are revealed at both cellular and molecular levels, and the character of its pathological ultrastructural alteration as the gist in cellular pathology for pathogenesis are also presented.

Objective: To evaluate the role of adiponectin in regulating tumor necrosis factor alpha (TNF alpha) production and preventing fulminant autoimmunological damage of hepatocytes following concanavalin A (Con A) injection into mice., Methods: Three days after recombinant plasmids pAA-neo-mAd were injected into the mice via the tail veins, Con A was injected into the mice. Mice transfected with empty pAA-neo vector served as controls. The serum levels of alanine aminotransferase (ALT), TNF alpha and adiponectin were detected, and histological examination of livers was carried out at different time points after the Con A injection. All results were subjected to statistical analyses., Results: Histological examinations showed that the damage in livers of mice with high serum adiponectin levels was milder than that of the controls. The serum levels of ALT and TNF alpha were both lower than those of the controls (P less than 0.01, respectively). Statistical analyses showed the serum levels of ALT was negatively related to the levels of adiponectin in the sera (r=-0.5034)., Conclusion: Adiponectin is effective in protecting hepatocytes from Con A-induced immunological injury. The mechanism of this protective effect may be caused by inhibiting the synthesis and/or release of TNF alpha.

RAPDs and AFLPs were used to investigate the genetic variation of 14 species of Cymbidium. A great diversity was shown by 12 random primers and three primer combinations. UPGMA cluster analysis showed that the results from the RAPD and AFLP analysis were similar and the genetic distances were closest between C. ensifolium and C. sinense, C. kanran and C. faberi var. omeiense, C. mastersii and C. eburneum respectively.

The presence in transgenic plants of antibiotic and herbicide resistant selective marker genes might be an unpredictable hazard to the ecosystem as well as to human health. There are two applicable strategies can be used to resolve this problem. One is to remove the resistant marker genes before the transgenic plants are released to field. The other is to develop and use safe marker genes to produce transgenic plants. The present paper reviewed three technique systems employed to remove resistant marker genes in transgenic plants and several safe marker genes used in plant transformation.

Virus disease is a major cause that affects the quality and output of watermelon which is an important fruit in summer. So it is really urgent to develop disease resistance plants. But it takes a long time to breed such plants in conventional ways, and it is very difficult to get ideal result. With the development of plant genetic engineering, new ways have been found to breed plants with disease resistance. By using plant transgenic technique, much progress was been made in plant improvement. There are many successful cases of transgenic plants against corresponding virus disease through transferring coat protein gene. This paper reports the results of inheritance, segregation, expression of WMV-2 coat protein gene in inbred transgenic watermelon and its resistance to virus. Through PCR analysis of inbred plants, we found WMV-2 coat protein gene in the genome of progeny R1 separated with 3:1. After successive selection and identification of 4 generations, 8 transgenic pure lines with almost the same agronomic traits were obtained from 3 independent transformants of T7, T11 and T32. The result of Western blotting shows all 3 different transgenic lines of R4T7-1, R4T11-3 and R4T32-7 can produce coat protein. Disease resistance experiment on transgenic plants with WMV-2 shows that, compared with the control groups, transgenic plants can delay the disease infection and reduce the incidence and the symptoms of virus disease. And the transgenic line R4T32-7 expressed high resistance to infection by WMV-2, which lays a foundation for breeding of disease resistant varieties through plant transgenic technique.