13 research outputs found
Content analysis of systematic reviews on the effectiveness of Traditional Chinese Medicine
AbstractObjectiveTo evaluate evidence for the efficacy of Traditional Chinese Medicine (TCM) in systematic reviews.MethodsChinese (TCMPeriodical Literature Database, Chinese Biological Medicine database, Chinese Medical Current Contents, China Hospital Knowledge Database journal fulltext database, Virtual Machining and Inspection System, and Wanfang) and English (Cochrane Database of Systematic Reviews, PubMed and Embase) databases were searched.ResultsThree thousand, nine hundred and fifty-five articles were initially identified, 606 of which met the inclusion criteria, including 251 in English (83 from the Cochrane Database) and 355 in Chinese. The number of articles published each year increased between 1989 and 2009. Cardiocerebrovascular disease was the most studied target disease. Intervention measures includedTCM preparations (177 articles), acupuncture (133 articles) and combinations of TCM and western medicine (38 articles). Control measures included positive medical (177 articles), basic treatment (100 articles), placebo (219 articles), and blank and mutual (107 articles). All articles included at least one reference; the greatest number was 268. Six of 10 articles with high quality references demonstrated curative effectsagainst target diseasesincludingupper respiratory tract infection, dementia and depression. Interventions that were not recommendedwere tripterygium for rheumatoid arthritis andTCM syndrome differentiation for pediatric nocturia. In 10.4% of the studies, the authors concluded that the intervention had a curative effect. The assessors agreed with the authors' conclusions in 88.32% of cases, but rejected 8.94% (54 articles).Conclusion1) Training in systematic review methods, including topic selection, study design, methods and technology, should be improved. 2) Upper respiratory tract infection, dementia and depression may become the predominant diseases treatedby TCM, and the corresponding interventions could be developed into practical applications. 3) Use of non-recommended interventions should be controlled, and there should be more research on side effects
Heterologous Expression of Alteromonas macleodii and Thiocapsa roseopersicina [NiFe] Hydrogenases in Synechococcus elongatus
Oxygen-tolerant [NiFe] hydrogenases may be used in future photobiological hydrogen production systems once the enzymes can be heterologously expressed in host organisms of interest. To achieve heterologous expression of [NiFe] hydrogenases in cyanobacteria, the two hydrogenase structural genes from Alteromonas macleodii Deep ecotype (AltDE), hynS and hynL, along with the surrounding genes in the gene operon of HynSL were cloned in a vector with an IPTG-inducible promoter and introduced into Synechococcus elongatus PCC7942. The hydrogenase protein was expressed at the correct size upon induction with IPTG. The heterologously-expressed HynSL hydrogenase was active when tested by in vitro H2 evolution assay, indicating the correct assembly of the catalytic center in the cyanobacterial host. Using a similar expression system, the hydrogenase structural genes from Thiocapsa roseopersicina (hynSL) and the entire set of known accessory genes were transferred to S. elongatus. A protein of the correct size was expressed but had no activity. However, when the 11 accessory genes from AltDE were co-expressed with hynSL, the T. roseopersicina hydrogenase was found to be active by in vitro assay. This is the first report of active, heterologously-expressed [NiFe] hydrogenases in cyanobacteria
Large expert-curated database for benchmarking document similarity detection in biomedical literature search
Document recommendation systems for locating relevant literature have mostly relied on methods developed a decade ago. This is largely due to the lack of a large offline gold-standard benchmark of relevant documents that cover a variety of research fields such that newly developed literature search techniques can be compared, improved and translated into practice. To overcome this bottleneck, we have established the RElevant LIterature SearcH consortium consisting of more than 1500 scientists from 84 countries, who have collectively annotated the relevance of over 180 000 PubMed-listed articles with regard to their respective seed (input) article/s. The majority of annotations were contributed by highly experienced, original authors of the seed articles. The collected data cover 76% of all unique PubMed Medical Subject Headings descriptors. No systematic biases were observed across different experience levels, research fields or time spent on annotations. More importantly, annotations of the same document pairs contributed by different scientists were highly concordant. We further show that the three representative baseline methods used to generate recommended articles for evaluation (Okapi Best Matching 25, Term Frequency-Inverse Document Frequency and PubMed Related Articles) had similar overall performances. Additionally, we found that these methods each tend to produce distinct collections of recommended articles, suggesting that a hybrid method may be required to completely capture all relevant articles. The established database server located at https://relishdb.ict.griffith.edu.au is freely available for the downloading of annotation data and the blind testing of new methods. We expect that this benchmark will be useful for stimulating the development of new powerful techniques for title and title/abstract-based search engines for relevant articles in biomedical research.Peer reviewe
Discovery of [NiFe] Hydrogenase Genes in Metagenomic DNA: Cloning and Heterologous Expression in Thiocapsa roseopersicina▿
Using a metagenomics approach, we have cloned a piece of environmental DNA from the Sargasso Sea that encodes an [NiFe] hydrogenase showing 60% identity to the large subunit and 64% to the small subunit of a Thiocapsa roseopersicina O2-tolerant [NiFe] hydrogenase. The DNA sequence of the hydrogenase identified by the metagenomic approach was subsequently found to be 99% identical to the hyaA and hyaB genes of an Alteromonas macleodii hydrogenase, indicating that it belongs to the Alteromonas clade. We were able to express our new Alteromonas hydrogenase in T. roseopersicina. Expression was accomplished by coexpressing only two accessory genes, hyaD and hupH, without the need to express any of the hyp accessory genes (hypABCDEF). These results suggest that the native accessory proteins in T. roseopersicina could substitute for the Alteromonas counterparts that are absent in the host to facilitate the assembly of a functional Alteromonas hydrogenase. To further compare the complex assembly machineries of these two [NiFe] hydrogenases, we performed complementation experiments by introducing the new Alteromonas hyaD gene into the T. roseopersicina hynD mutant. Interestingly, Alteromonas endopeptidase HyaD could complement T. roseopersicina HynD to cleave endoproteolytically the C-terminal end of the T. roseopersicina HynL hydrogenase large subunit and activate the enzyme. This study refines our knowledge on the selectivity and pleiotropy of the elements of the [NiFe] hydrogenase assembly machineries. It also provides a model for functionally analyzing novel enzymes from environmental microbes in a culture-independent manner