Amorpha-4,11-diene synthase (ADS) of Artemisia annua catalyzes the conversion of farnesyl diphosphate into amorpha-4,11-diene, the first committed step in the biosynthesis of the antimalarial drug artemisinin. The promoters of ADS contain two reverse-oriented TTGACC W-box cis-acting elements, which are the proposed binding sites of WRKY transcription factors. A full-length cDNA (AaWRKY1) was isolated from a cDNA library of the glandular secretory trichomes (GSTs) in which artemisinin is synthesized and sequestered. AaWRKY1 encodes a 311 amino acid protein containing a single WRKY domain. AaWRKY1 and ADS genes were highly expressed in GSTs and both were strongly induced by methyl jasmonate and chitosan. Transient expression analysis of the AaWRKY1-GFP (green fluorescent protein) reporter revealed that AaWRKY1 was targeted to nuclei. Biochemical analysis demonstrated that the AaWRKY1 protein was capable of binding to the W-box cis-acting elements of the ADS promoters, and it demonstrated transactivation activity in yeast. Co-expression of the effector construct 35S::AaWRKY1 with a reporter construct ADSpro1::GUS greatly activated expression of the GUS (beta-glucuronidase) gene in stably transformed tobacco. Furthermore, transient expression experiments in agroinfiltrated Nicotiana benthamiana and A. annua leaves showed that AaWRKY1 protein transactivated the ADSpro2 promoter activity by binding to the W-box of the promoter; disruption of the W-box abolished the activation. Transient expression of AaWRKY1 cDNA in A. annua leaves clearly activated the expression of the majority of artemisinin biosynthetic genes. These results strongly suggest the involvement of the AaWRKY1 transcription factor in the regulation of artemisinin biosynthesis, and indicate that ADS is a target gene of AaWRKY1 in A. annua.

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A type III polyketide synthase cDNA and the corresponding gene (PcPKS2) were cloned from Polygonum cuspidatum Sieb. et Zucc. Sequencing results showed that the ORF of PcPKS2 was interrupted by three introns, which was an unexpected finding because all type III PKS genes studied so far contained only one intron at a conserved site in flowering plants, except for an Antirrhinum majus chalcone synthase gene. Besides the unusual gene structure, PcPKS2 showed some interesting characteristics: (1) the CHS "gatekeepers" Phe215 and Phe265 are uniquely replaced by Leu and Cys, respectively; (2) recombinant PcPKS2 overexpressed in Escherichia coli efficiently afforded 4-coumaroyltriacetic acid lactone (CTAL) as a major product along with bis-noryangonin (BNY) and p-hydroxybenzalacetone at low pH; however, it effectively yielded p-hydroxybenzalacetone as a dominant product along with CTAL and BNY at high pH. Beside p-hydroxybenzalacetone, CTAL and BNY, a trace amount of naringenin chalcone could be detected in assays at different pH. Furthermore, 4-coumaroyl-CoA and feruloyl-CoA were the only cinnamoyl-CoA derivatives accepted as starter substrates. PcPKS2 did not accept isobutyryl-CoA, isovaleryl-CoA or acetyl-CoA as substrate. DNA gel blot analysis indicated that there are two to four PcPKS2 copies in the P. cuspidatum genome. RNA gel blot analysis revealed that PcPKS2 is highly expressed in the rhizomes and in young leaves, but not in the roots of the plant. PcPKS2 transcripts in leaves were induced by pathogen infection, but not by wounding.

Background:Good's syndrome (GS) is a rare disease characterized by thymoma, hypogammaglobulinemia, low or absent B-cells, decreased T-cells, an inverted CD4+/CD8+ T-cell ratio and reduced T-cell mitogen proliferative responses. GS is difficult to diagnose preoperatively due to its rarity and lack of typical symptoms, the characteristics of Chinese GS patients are still lacking. This study aimed to systematically review all the clinical, laboratory, and immunologic findings of reported cases of Chinese patients with GS.Methods:We searched for case reports and articles up to January 2017 using PubMed, China National Knowledge Infrastructure, Wangfang database and China Science and Technology Journal Database with the following words in combinations as key words: “thymoma,” “hypogammaglobulinemia,” and “Good's syndrome.” The text words and MeSH terms were entered depending on the databases characteristics. The reference lists from retrieved articles were also screened for additional applicable studies. The authors were restricted to Chinese. There was no language restriction.Results:Forty-seven patients were reported in 27 studies. We found that GS has a nationwide distribution and that most cases (83%) have been described on the mainland of China. The initial clinical presentation is varied, ranging from symptoms related to the thymoma to infections resulting from immunodeficiency. Type AB (50%) is the most common histologic type of thymomas in Chinese GS patients according to the World Health Organization classification of thymomas. With respect to infection, sinopulmonary infection (74%) is the most common type, followed by skin infection (10%) and intestinal tract infection (10%). Diarrhea was presented in 36% of patients, and autoimmune manifestations were presented in 36% of patients.Conclusions:GS is a rare association of thymoma and immunodeficiency with a poor prognosis. Astute clinical acumen and increased awareness of the clinical and immunological profile of GS are needed to increase early diagnosis, that would benefit improved therapeutic effects.

Objective Helicobacter pyloriinfection is mostly a family-based infectious disease. To facilitate its prevention and management, a national consensus meeting was held to review current evidence and propose strategies for population-wide and family-basedH. pyloriinfection control and management to reduce the related disease burden. Methods Fifty-seven experts from 41 major universities and institutions in 20 provinces/regions of mainland China were invited to review evidence and modify statements using Delphi process and grading of recommendations assessment, development and evaluation system. The consensus level was defined as ≥80% for agreement on the proposed statements. Results Experts discussed and modified the original 23 statements on family-basedH. pyloriinfection transmission, control and management, and reached consensus on 16 statements. The final report consists of three parts: (1)H. pyloriinfection and transmission among family members, (2) prevention and management ofH. pyloriinfection in children and elderly people within households, and (3) strategies for prevention and management ofH. pyloriinfection for family members. In addition to the ‘test-and-treat’ and ‘screen-and-treat’ strategies, this consensus also introduced a novel third ‘family-basedH. pyloriinfection control and management’ strategy to prevent its intrafamilial transmission and development of related diseases. Conclusion H. pyloriis transmissible from person to person, and among family members. A family-basedH. pyloriprevention and eradication strategy would be a suitable approach to prevent its intra-familial transmission and related diseases. The notion and practice would be beneficial not only for Chinese residents but also valuable as a reference for other highly infected areas.

The purpose of the study is to evaluate a new immunochemical fecal occult blood test method (Hemosure IFOBT), and compare it to the Guaiac-based chemical method (CFOBT) for colorectal cancer detection. A hypothetical sequential method (SFOBT), in which IFOBT was used only as a confirmatory test for CFOBT, was also evaluated. A total of 324 patients were recruited from 5 major hospitals in Beijing, China. For each patient, 3 consecutive stool samples were collected for simultaneous CFOBT and IFOBT tests, followed by colonoscopic examination. We compared the sensitivity and specificity of the 3 methods (CFOBT, IFOBT and SFOBT) in two settings, with the first 2 consecutive samples versus all 3 samples. Although the sensitivity for the detection of cancer and large (>20 mm) or multiple adenoma was similar for all 3 methods in the three-sample setting, in the two-sample setting IFOBT had higher sensitivity than SFOBT for detecting cancer (87.8% vs. 75.5%, respectively, p < 0.05) and large (>20 mm) or multiple adenomas (65.4% vs. 42.3%, respectively, p < 0.05). The IFOBT also had a higher specificity than the CFOBT (89.2% vs. 75.5%, respectively, p < 0.01) in ''normal'' individuals defined by colonoscopy in the three-sample setting. Comparing two-sample setting to the three-sample setting, both CFOBT and SFOBT showed significant loss of sensitivity for the detection of cancer as well as adenoma, whereas the sensitivity for IFOBT did not change significantly. Overall, IFOBT with two-sample testing showed compatible sensitivity and specificity to the three-sample testing, and had a lower relative cost per cancer detected than the three-sample testing. In conclusion, the new Hemosure IFOBT with two consecutive stool samples appears to be the most costeffective approach for colon cancer screening. ' 2006 Wiley-Liss, Inc.