Cytochemical and comparative transcriptome analyses elucidate the formation and ecological adaptation of three types of pollen coat in Zingiberaceae.

BACKGROUND: The pollen ornate surface of flowering plants has long fascinated and puzzled evolutionary biologists for their variety. Each pollen grain is contained within a pollen wall consisting of intine and exine, over which the lipoid pollen coat lies. The cytology and molecular biology of the development of the intine and exine components of the pollen wall are relatively well characterised. However, little is known about the pollen coat, which confers species specificity. We demonstrate three types of pollen coat in Zingiberaceae, a mucilage-like pollen coat and a gum-like pollen coat, along with a pollen coat more typical of angiosperms. The morphological differences between the three types of pollen coat and the related molecular mechanisms of their formation were studied using an integrative approach of cytology, RNA-seq and positive selection analysis. RESULTS: Contrary to the 'typical' pollen coat, in ginger species with a mucilage-like (Caulokaempferia coenobialis, Cco) or gum-like (Hornstedtia hainanensis, Hhn) pollen coat, anther locular fluid was still present at the bicellular pollen (BCP) stage of development. Nevertheless, there were marked differences between these species: there were much lower levels of anther locular fluid in Hhn at the BCP stage and it contained less polysaccharide, but more lipid, than the locular fluid of Cco. The set of specific highly-expressed (SHE) genes in Cco was enriched in the 'polysaccharide metabolic process' annotation term, while 'fatty acid degradation' and 'metabolism of terpenoids and polyketides' were significantly enriched in SHE-Hhn. CONCLUSIONS: Our cytological and comparative transcriptome analysis showed that different types of pollen coat depend on the residual amount and composition of anther locular fluid at the BCP stage. The genes involved in 'polysaccharide metabolism' and 'transport' in the development of a mucilage-like pollen coat and in 'lipid metabolism' and 'transport' in the development of a gum-like pollen coat probably evolved under positive selection in both cases. We suggest that the shift from a typical pollen coat to a gum-like or mucilage-like pollen coat in flowering plants is an adaptation to habitats with high humidity and scarcity of pollinators.

Population genetic structure and connectivity of a riparian selfing herb Caulokaempferia coenobialis at a fine-scale geographic level in subtropical monsoon forest.

BACKGROUND: Rivers and streams facilitate movement of individuals and their genes across the landscape and are generally recognized as dispersal corridors for riparian plants. Nevertheless, some authors have reported directly contrasting results, which may be attributed to a complex mixture of factors, such as the mating system and dispersal mechanisms of propagules (seed and pollen), that make it difficult to predict the genetic diversity and population structure of riparian species. Here, we investigated a riparian self-fertilizing herb Caulokaempferia coenobialis, which does not use anemochory or zoochory for seed dispersal; such studies could contribute to an improved understanding of the effect of rivers or streams on population genetic diversity and structure in riparian plants. Using polymorphic ISSR and cpDNA loci, we studied the effect at a microgeographic scale of different stream systems (a linear stream, a dendritic stream, and complex transverse hydrological system) in subtropical monsoon forest on the genetic structure and connectivity of C. coenobialis populations across Dinghu Mountain (DH) and Nankun Mountain (NK). RESULTS: The results indicate that the most recent haplotypes (DH: H7, H8; NK: h6, h7, h11, h12) are not shared among local populations of C. coenobialis within each stream system. Furthermore, downstream local populations do not accumulate genetic diversity, whether in the linear streamside local populations across DH (H: 0.091 vs 0.136) or the dendritic streamside local populations across NK (H: 0.079 vs 0.112, 0.110). Our results show that the connectivity of local C. coenobialis populations across DH and NK can be attributed to historical gene flows, resulting in a lack of spatial genetic structure, despite self-fertilization. Selfing C. coenobialis can maintain high genetic diversity (H = 0.251; I = 0.382) through genetic differentiation (GST = 0.5915; FST = 0.663), which is intensified by local adaptation and neutral mutation and/or genetic drift in local populations at a microgeographic scale. CONCLUSION: We suggest that streams are not acting as corridors for dispersal of C. coenobialis, and conservation strategies for maintaining genetic diversity of selfing species should be focused on the protection of all habitat types, especially isolated fragments in ecosystem processes.

Glucagon-like peptide-1 receptor agonists and heart failure in type 2 diabetes: systematic review and meta-analysis of randomized and observational studies.

BACKGROUND: The effect of glucagon-like peptide-1(GLP-1) receptor agonists on heart failure remains uncertain. We therefore conducted a systematic review to assess the possible impact of GLP-1 agonists on heart failure or hospitalization for heart failure in patients with type 2 diabetes. METHODS: We searched MEDLINE, EMBASE, the Cochrane Central Register of Controlled Trials (CENTRAL) and ClinicalTrials.gov to identify randomized controlled trials (RCTs) and observational studies that addressed the effect of GLP-1 receptor agonists in adults with type 2 diabetes, and explicitly reported heart failure or hospitalization for heart failure. Two paired reviewers screened reports, collected data, and assessed the risk of bias. We pooled data from RCTs and observational studies separately, and used the GRADE approach to rate the quality of evidence. RESULTS: We identified 25 studies that were eligible for our review; 21 RCTs (n = 18,270) and 4 observational studies (n = 111,029). Low quality evidence from 20 RCTs suggested, if anything, a lower incidence of heart failure between GLP-1 agonists versus control (17/7,441 vs. 19/4,317; odds ratio (OR) 0.62, 95 % confidence interval (CI) 0.31 to 1.22; risk difference (RD) 19 fewer, 95 % CI 34 fewer to 11 more per 1000 over 5 years). Three cohort studies comparing GLP-1 agonists to alternative agents provided very low quality evidence that GLP-1 agonists do not increase the incidence of heart failure. One RCT provided moderate quality evidence that GLP-1 agonists were not associated with hospitalization for heart failure (lixisenatide vs placebo: 122/3,034 vs. 127/3,034; adjusted hazard ratio 0.96, 95 % CI 0.75 to 1.23; RD 4 fewer, 95 % CI 25 fewer to 23 more per 1000 over 5 years) and a case-control study provided very low quality evidence also suggesting no association (GLP-1 agonists vs. other anti-hyperglycemic drugs: 1118 cases and 17,626 controls, adjusted OR 0.67, 95 % CI 0.32 to 1.42). CONCLUSIONS: The current evidence suggests that GLP-1 agonists do not increase the risk of heart failure or hospitalization for heart failure among patients with type 2 diabetes.

Vacuum frying of peas: effect of coating and pre-drying.

The objective of the research was to compare the effect of coating with sodium carboxymethyl cellulose, hot-air and vacuum microwave pre-drying on the physicochemical properties and sensory scores of vacuum-fried peas. The three pre-treatments prior to frying were shown to obviously reduce oil absorption in vacuum-fried peas. Among the three pre-treatments, coating with sodium carboxymethyl cellulose for peas produced the lowest oil content products (24.53 %), and the chlorophyll retention was 77.08 %. Vitamin C and breaking force for fried products with vacuum microwave pre-drying were 46.56 µg/100 g (db) and 8.64 N, which were significantly (P ≤ 0.05) better than those of other treatments. However, fried peas treated by hot air pre-drying showed the highest breaking force and lowest chlorophyll retention. All the fried peas had water activity (Aw) values of less than 0.35, indicating that the products have a long shelf life. Sensory scores showed vacuum-fried peas treated by vacuum microwave pre-drying had the highest acceptability.

Transcriptional regulations of pollen tube reception are associated with the fertility of the ginger species Zingiber zerumbet and Zingiber corallinum.

Zingiber zerumbet and Zingiber corallinum are economically valuable species in the genus Zingiber. While Z. corallinum is sexually active, Z. zerumbet adopts clonal propagation, although it has the potential for sexual reproduction. It is unclear so far at which step during the sexual reproduction of Z. zerumbet inhibition occurs, and what are the regulatory mechanisms underlying this inhibition. Here, by comparing with the fertile species Z. corallinum using microscopy-based methods, we show that rare differences were observed in Z. zerumbet up to the point when the pollen tubes invaded the ovules. However, a significantly higher percentage of ovules still contained intact pollen tubes 24 h after pollination, suggesting pollen tube rupture was impaired in this species. Further RNA-seq analysis generated accordant results, showing that the transcription of ANX and FER, as well as genes for the partners in the same complexes (e.g., BUPS and LRE, respectively), and those putative peptide signals (e.g., RALF34), were timely activated in Z. corallinum, which ensured the pollen tubes being able to grow, reorient to ovules, and receipt by embryo sacs. In Z. zerumbet, genes for these complexes were cooperatively suppressed, which would result in the maintenance of PT integrity due to the disruption of RALF34-ANX/BUPS signaling in PT and the failure of PT reception by an active synergid due to the insufficiency of the synergid-harbored FER/LRE complex. Taking the results from the cytological and RNA-seq studies together, a model is proposed to illustrate the possible regulation mechanisms in Z. zerumbet and Z. corallinum, in which the regulations for pollen tube rupture and reception are proposed as the barrier for sexual reproduction in Z. zerumbet.

Leaf epidermal micromorphology of Zingiber (Zingiberaceae) from China and its systematic significance.

Leaf epidermal characteristics are important for phylogenetic and taxonomic studies of many plants, but there is currently insufficient such data for this application in Zingiber species. Therefore, the leaf epidermal micromorphology of 22 species in three sections of Zingiber was investigated by light microscopy and scanning electron microscopy. Differences between various taxonomic groups of Zingiberaceae were also compared to assess their phylogenetic and taxonomic significance. As in other genera of Zingiberaceae, the epidermal cells in both the adaxial and abaxial epidermis of Zingiber species were found to be hexagonal or polygonal, with non-sinuous anticlinal walls that are arranged parallel to leaf veins. Tetracytic stomata are mostly randomly distributed in the intercostal regions of both surfaces and are more common on the abaxial surface. The stomatal density of the species in sect. Pleuranthesis is significantly lower than that in sects. Zingiber and Cryptanthium. There are two types of trichome in Zingiber: so-called "delicate" trichomes are present in most species, while "stout" trichomes with a swollen base are only found in Z.corallinum and Z.montanum. Oil cells occur in both epidermal layers of some species in sects. Zingiber and Cryptanthium, but only in the abaxial epidermis of Z.ellipticum in sect. Pleuranthesis. Crystals are found in the abaxial epidermis only in all species, but are present in both epidermal layers of Z.corallinum and Z.montanum. Although the epidermal morphology is similar in most Zingiber species, stomatal density, type of trichome and distribution of oil cells and crystals offer valuable information for the systematic and taxonomic studies in this genus.

Genetic variation and population structure of clonal Zingiber zerumbet at a fine geographic scale: a comparison with two closely related selfing and outcrossing Zingiber species.

BACKGROUND: There has always been controversy over whether clonal plants have lower genetic diversity than plants that reproduce sexually. These conflicts could be attributed to the fact that few studies have taken into account the mating system of sexually reproducing plants and their phylogenetic distance. Moreover, most clonal plants in these previous studies regularly produce sexual progeny. Here, we describe a study examining the levels of genetic diversity and differentiation within and between local populations of fully clonal Zingiber zerumbet at a microgeographical scale and compare the results with data for the closely related selfing Z. corallinum and outcrossing Z. nudicarpum. Such studies could disentangle the phylogenetic and sexually reproducing effect on genetic variation of clonal plants, and thus contribute to an improved understanding in the clonally reproducing effects on genetic diversity and population structure. RESULTS: The results revealed that the level of local population genetic diversity of clonal Z. zerumbet was comparable to that of outcrossing Z. nudicarpum and significantly higher than that of selfing Z. corallinum. However, the level of microgeographic genetic diversity of clonal Z. zerumbet is comparable to that of selfing Z. corallinum and even slightly higher than that of outcrossing Z. nudicarpum. The genetic differentiation among local populations of clonal Z. zerumbet was significantly lower than that of selfing Z. corallinum, but higher than that of outcrossing Z. nudicarpum. A stronger spatial genetic structure appeared within local populations of Z. zerumbet compared with selfing Z. corallinum and outcrossing Z. nudicarpum. CONCLUSIONS: Our study shows that fully clonal plants are able not only to maintain a high level of within-population genetic diversity like outcrossing plants, but can also maintain a high level of microgeographic genetic diversity like selfing plant species, probably due to the accumulation of somatic mutations and absence of a capacity for sexual reproduction. We suggest that conservation strategies for the genetic diversity of clonal and selfing plant species should be focused on the protection of all habitat types, especially fragments within ecosystems, while maintenance of large populations is a key to enhance the genetic diversity of outcrossing species.

Genetic variation and genetic structure within metapopulations of two closely related selfing and outcrossing Zingiber species (Zingiberaceae).

Habitat fragmentation strongly affects the genetic diversity of plant populations, and this has always attracted much research interest. Although numerous studies have investigated the effects of habitat fragmentation on the genetic diversity of plant populations, fewer studies have compared species with contrasting breeding systems while accounting for phylogenetic distance. Here, we compare the levels of genetic diversity and differentiation within and among subpopulations in metapopulations (at fine-scale level) of two closely related Zingiber species, selfing Zingiber corallinum and outcrossing Zingiber nudicarpum. Comparisons of the genetic structure of species from unrelated taxa may be confounded by the effects of correlated ecological traits or/and phylogeny. Thus, we possibly reveal the differences in genetic diversity and spatial distribution of genetic variation within metapopulations that relate to mating systems. Compared to outcrossing Z. nudicarpum, the subpopulation genetic diversity in selfing Z. corallinum was significantly lower, but the metapopulation genetic diversity was not different. Most genetic variation resided among subpopulations in selfing Z. corallinum metapopulations, while a significant portion of variation resided either within or among subpopulations in outcrossing Z. nudicarpum, depending on whether the degree of subpopulation isolation surpasses the dispersal ability of pollen and seed. A stronger spatial genetic structure appeared within subpopulations of selfing Z. corallinum potentially due to restricted pollen flow and seed dispersal. In contrast, a weaker genetic structure was apparent in subpopulations of outcrossing Z. nudicarpum most likely caused by extensive pollen movement. Our study shows that high genetic variation can be maintained within metapopulations of selfing Zingiber species, due to increased genetic differentiation intensified primarily by the stochastic force of genetic drift among subpopulations. Therefore, maintenance of natural variability among subpopulations in fragmented areas is key to conserve the full range of genetic diversity of selfing Zingiber species. For outcrossing Zingiber species, maintenance of large populations is an important factor to enhance genetic diversity. Compared to outcrossing Z. nudicarpum, the subpopulation genetic diversity in selfing Z. corallinum was significantly lower, but the metapopulation genetic diversity did not differ. Most genetic variation resided among subpopulations in selfing Z. corallinum metapopulations, while a significant portion of variation resided either within or among subpopulations in outcrossing Z. nudicarpum, depending on whether the degree of subpopulation isolation surpasses the dispersal ability of pollen and seed. Our study shows that selfing Z. corallinum could maintain high genetic diversity through differentiation intensified primarily by the stochastic force of genetic drift among subpopulations at fine-scale level, but not local adaptation.

Botany: a new self-pollination mechanism.

Pollen grains from most flowering plants are transported by wind or animals and deposited on the receptive surface of the stigma of a different individual, but self-pollination is also common. We have discovered a new process for self-pollination in the laterally orientated flowers of a Chinese herb, in which a film of pollen is transported from the anther (pollen sacs) by an oily emulsion that slides sideways along the flower's style and into the individual's own stigma. This mode of self-pollination is a new addition to the broad range of genetic and morphological mechanisms that have evolved in flowering plants (angiosperms), and may be common in species growing in shady, windless and insect-poor habitats.

[Characteristics of African swine fever virus and difficulties in vaccine development].

African swine fever (ASF) is a devastating disease of pigs caused by African swine fever virus (ASFV), which is considered to be the No. 1 killer to the global pig industry. Highly virulent strains are usually responsible for the peracute and acute forms that provoke high mortality rates that may reach 100%. Since ASF was first introduced in August 2018 into China, 137 outbreaks in domestic and wild pigs had been reported from 32 provinces by June 06, 2019, causing severe socioeconomic consequences. Efforts to develop an ASFV vaccine began in the 1960s, but all failed, the major reason is the lack of in-depth research on the biological characteristics of ASFV. It will be a great challenge for China to control the spread of current ASF, develop safe and effective vaccines. In this review, we outline the biological characteristics of ASFV, including its morphology and basic structure, transmission routes, pathogenicity, genome and proteins, entry mechanism, immune escape, and analyzed the difficulties in vaccine development. We hope to provide basic information for the control of current ASF and understanding of etiology in China.

Concentrations of polycyclic aromatic hydrocarbons in street dust from bus stops in Qingyang city: Estimates of lifetime cancer risk and sources of exposure for daily commuters in Northwest China.

Lifetime cancer risk and exposure of daily commuters to polycyclic aromatic hydrocarbons (PAHs) in cities of Northwest China were determined from a study of street dust samples obtained from bus stops in Qingyang city. The sum of 16 priority PAHs (Σ16 PAHs) concentrations in the dust samples ranged from 0.8 to 18.3 mg kg-1 (mean 3.0 mg kg-1) and the distribution of individual, carcinogenic, combustion specific, low (2-3 rings) and high molecular weight (4-6 rings) PAHs was determined. The benzo[a]pyrene toxic equivalents of Σ16 PAHs ranged from 0.01 to 12.2 mg kg-1 (mean 0.8 mg kg-1). Incremental lifetime cancer risk from exposure to PAHs in dust at bus stops in Qingyang city was estimated at 1.9 × 10-6 for adults and 3.5 × 10-6 for children (confidence limit ≥ 95%). Emission source analysis of PAHs in bus stop dust showed that they were mainly derived from residential coal, oil and biomass combustion, e.g. from boilers, traffic vehicles, and Kang heaters. Higher concentrations of PAHs were obtained at bus stops near transport hubs, commercial districts, and administrative institutions.

Genetic differentiation between two varieties of Oreocharis benthamii (Gesneriaceae) in sympatric and allopatric regions.

The pattern of genetic differentiation between diverging species receives much attention as one of the key observable features of speciation. It has often been suggested that introgression between closely related species occurs commonly where their distributions overlap, leading to their becoming more morphologically and genetically similar, but there are a few opposite results. However, most of these studies have been carried out with animals and separate species; few have looked at intraspecific cases, especially in plants. Here, we conduct a comparative study on patterns of genetic differentiation among populations of two varieties of Oreocharis benthamii in allopatry and sympatry based on ISSR data for 754 individuals from 26 populations, in order to understand the processes leading to speciation. Contrary to expectations, the facultative xenogamy (mixed mating) species O. benthamii has a relatively low genetic diversity within populations (H = 0.1014, I = 0.1528) and high genetic differentiation among populations (G ST = 0.5867, ФST = 0.659), as is typically found for selfing species. Genetic variance between the two varieties in sympatric populations (44%, ФST = 0.444) is significantly more than that in allopatric populations (14%, ФST = 0.138). Consistent with the taxonomical delimitation of the two varieties, all sampled individuals of O. benthamii clustered into two genetic groups. Moreover, the genetic structures of populations of both varieties are correlated with their different geographical origins. Our studies show that significant divergence between sympatric populations of the two varieties could be attributed primarily to reinforcement by genetic divergent selection in sympatry where secondary contact had occurred. The major proportion of the genetic variation in outcrossing and mixed mating plants may exist among populations when the populations are distributed in fragmented habitats, due to the paucity of suitable habitat combined with inefficient seed dispersal mechanism and limited pollinator foraging area that may limit the gene flow.

Oreocharisodontopetala, a new species of Gesneriaceae from Guizhou, China.

A new species, Oreocharisodontopetala Q.Fu & Y.Q.Wang from Guizhou Province in southwest China, is described and illustrated, based on morphological comparison with existing species. It is morphologically most similar to O.elegantissima, but can be easily distinguished by its adaxially bullate leaf blade, abaxially conspicuous reticulate veinlets, brown-purple peduncles, triangular adaxial corolla lobes and abaxial corolla lobe margins bearing 4-10 long teeth, glabrous style and shorter stamens with confluent thecae at the apex, as well as leaf epidermal characters.

Comparative studies on population genetic structure of two closely related selfing and outcrossing Zingiber species in Hainan Island.

How mating system impacts the genetic diversity of plants has long fascinated and puzzled evolutionary biologists. Numerous studies have shown that self-fertilising plants have less genetic diversity at both the population and species levels than outcrossers. However, the phylogenetic relationships between species and correlated ecological traits have not been accounted for in these previous studies. Here, we conduct a comparative population genetic study of two closely related selfing and outcrossing Zingiber species, with sympatric distribution in Hainan Island, and obtain a result contrary to previous studies. The results indicate that selfing Z. corallinum can maintain high genetic diversity through differentiation intensified by local adaptation in populations across the species' range. In contrast, outcrossing Z. nudicarpum preserves high genetic diversity through gene exchange by frequent export of pollen within or among populations. Contrary to expectations, the major portion of genetic variation of outcrossing Z. nudicarpum may exist among populations, depending on the dispersal ability of pollen and seed. Our results also reveal that the main factor affecting population structure of selfing Z. corallinum is mountain ranges, followed by a moist climate, while that of outcrossing Z. nudicarpum is likely moisture, but not mountain ranges, due to gene flow via pollen.

Dipeptidyl peptidase-4 inhibitors and risk of heart failure in type 2 diabetes: systematic review and meta-analysis of randomised and observational studies.

OBJECTIVES: To examine the association between dipeptidyl peptidase-4 (DPP-4) inhibitors and the risk of heart failure or hospital admission for heart failure in patients with type 2 diabetes. DESIGN: Systematic review and meta-analysis of randomised and observational studies. DATA SOURCES: Medline, Embase, Cochrane Central Register of Controlled Trials, and ClinicalTrials.gov searched up to 25 June 2015, and communication with experts. ELIGIBILITY CRITERIA: Randomised controlled trials, non-randomised controlled trials, cohort studies, and case-control studies that compared DPP-4 inhibitors against placebo, lifestyle modification, or active antidiabetic drugs in adults with type 2 diabetes, and explicitly reported the outcome of heart failure or hospital admission for heart failure. DATA COLLECTION AND ANALYSIS: Teams of paired reviewers independently screened for eligible studies, assessed risk of bias, and extracted data using standardised, pilot tested forms. Data from trials and observational studies were pooled separately; quality of evidence was assessed by the GRADE approach. RESULTS: Eligible studies included 43 trials (n=68,775) and 12 observational studies (nine cohort studies, three nested case-control studies; n=1,777,358). Pooling of 38 trials reporting heart failure provided low quality evidence for a possible similar risk of heart failure between DPP-4 inhibitor use versus control (42/15,701 v 33/12,591; odds ratio 0.97 (95% confidence interval 0.61 to 1.56); risk difference 2 fewer (19 fewer to 28 more) events per 1000 patients with type 2 diabetes over five years). The observational studies provided effect estimates generally consistent with trial findings, but with very low quality evidence. Pooling of the five trials reporting admission for heart failure provided moderate quality evidence for an increased risk in patients treated with DPP-4 inhibitors versus control (622/18,554 v 552/18,474; 1.13 (1.00 to 1.26); 8 more (0 more to 16 more)). The pooling of adjusted estimates from observational studies similarly suggested (with very low quality evidence) a possible increased risk of admission for heart failure (adjusted odds ratio 1.41, 95% confidence interval 0.95 to 2.09) in patients treated with DPP-4 inhibitors (exclusively sitagliptin) versus no use. CONCLUSIONS: The relative effect of DPP-4 inhibitors on the risk of heart failure in patients with type 2 diabetes is uncertain, given the relatively short follow-up and low quality of evidence. Both randomised controlled trials and observational studies, however, suggest that these drugs may increase the risk of hospital admission for heart failure in those patients with existing cardiovascular diseases or multiple risk factors for vascular diseases, compared with no use.

The concrete evidence of flexistyly in Plagiostachys: pollination biology of a wild ginger on Hainan Island, China.

Flexistyly in Plagiostachys was first reported by Takano et al., while they provided no detailed study on pollination biology and breeding system. In this study, we tested this suspicion in one species of Plagiostachys (Plagiostachys austrosinensis). Field observations suggested that flexistyly was present in this species, and stigmatic behavior was similar to that reported for Alpinia and Amomum species. Two phenotypes (anaflexistylous and cataflexistylous) occurred in a ratio of 1:1 in natural populations. Anthesis began around 1530-1600 h and lasted for about 24 h. Pollen viability and stigma receptivity remained high throughout the flowering process. Mean nectar volume (4.15-11.30 µL) and mean sugar concentration (>32%) also remained at a high level during the flowering process. No fruit set occurred in unpollinated bagged plants. Two pollinators (Bombus pyrosoma and Vespidae spp.) and one pollen robber (Mutillidae spp.) were found as flower visitors. Fruit set following self-pollination and cross-pollination did not differ significantly in the cataflexistylous morph. Partial self-incompatibility was apparent in the anaflexistylous morph. These results provide the concrete evidence of flexistyly in Plagiostachys and a more thorough understanding of its evolutionary origin in gingers.

Triclosan inhibits enoyl-reductase of type I fatty acid synthase in vitro and is cytotoxic to MCF-7 and SKBr-3 breast cancer cells.

BACKGROUND AND PURPOSE: Human type I fatty acid synthase has been proposed as a chemotherapeutic target for the treatment of breast cancer based on the inactivation of human beta-ketoacyl synthase activity by cerulenin. Triclosan, a common antibiotic, functions by inhibiting the enoyl-reductase enzymes of type II fatty acid synthases in susceptible bacteria. If triclosan is an inhibitor of human fatty acid synthase and if inhibition of fatty acid synthase is toxic to breast cancer cell lines, triclosan could prove to be a lead compound for the treatment of breast cancer. Consequently, the inhibitory activity of triclosan against vertebrate type I fatty acid synthases and its effects on breast cancer lines in cell culture were investigated. METHODS: The inhibitory activities of triclosan against human and goose fatty acid synthases and each of the partial reactions were investigated using spectrophotometric assays. The ability of triclosan at various concentrations to inhibit growth and reduce the viability of MCF-7 and SKBr-3 cells in culture was evaluated. RESULTS: Kinetic studies showed triclosan to be a slow binding inhibitor of human and goose type I fatty acid synthase and to inhibit the partial activity of enoyl-reductase with IC(50) values between 10 and 50 microM. Triclosan at similar concentrations was also shown to inhibit both viability and growth of MCF-7 and SKBr-3 cells in culture. CONCLUSIONS: The results corroborate the hypothesis that fatty acid synthase may be a target of breast cancer chemotherapy and suggest that inhibitors of the enoyl-reductase partial activity of fatty acid synthase may have chemotherapeutic potential.

Radiofrequency ablation versus hepatic resection for small hepatocellular carcinomas: a meta-analysis of randomized and nonrandomized controlled trials.

OBJECTIVES: To evaluate the efficacy and safety of radiofrequency ablation (RFA) versus hepatic resection (HR) for early hepatocellular carcinoma (HCC) meeting the Milan criteria. METHODS: A meta-analysis was conducted, and PubMed, Web of Science, the Cochrane Library, CBM, CNKI and VIP databases were systematically searched through November 2012 for randomized and nonrandomized controlled trials (RCTs and NRCTs). The Cochrane Collaboration's tool and modified MINORS score were applied to assess the quality of RCTs and NRCTs, respectively. The GRADE approach was employed to evaluate the strength of evidence. RESULTS: Three RCTs and twenty-five NRCTs were included. Among 11,873 patients involved, 6,094 patients were treated with RFA, and 5,779 with HR. The pooled results of RCTs demonstrated no significant difference between groups for 1- and 3-year overall survival (OS), recurrence-free survival (RFS) and disease-free survival (DFS) (p>0.05). The 5-year OS (Relative Risk, RR 0.72, 95% CI 0.60 to 0.88) and RFS (RR 0.56, 95% CI 0.40 to 0.78) were lower with RFA than with HR. The 3- and 5-year recurrences with RFA were higher than with HR (RR 1.48, 95% CI 1.14 to 1.94, and RR 1.52, 95% CI 1.18 to 1.97, respectively), but 1-year recurrence and in-hospital mortality showed no significant differences between groups (p>0.05). The complication rate (RR 0.18, 95% CI 0.06 to 0.53) was lower and hospital stays (Mean difference -8.77, 95% CI -10.36 to -7.18) were shorter with RFA than with HR. The pooled results of NRCTs showed that the RFA group had lower 1-, 3- and 5-year OS, RFS and DFS, and higher recurrence than the HR group (p<0.05). But for patients with very early stage HCC, RFA was comparable to HR for OS and recurrence. CONCLUSION: The effectiveness of RFA is comparable to HR, with fewer complications but higher recurrence, especially for very early HCC patients.

A systematic assessment of the quality of systematic reviews/meta-analyses in radiofrequency ablation versus hepatic resection for small hepatocellular carcinoma.

OBJECTIVES: The systematic reviews (SRs) of radiofrequency ablation (RFA) versus hepatic resection (HR) for early hepatocellular carcinoma (HCC) are increasing with varies qualities. The aim of this study is to evaluate quality and their impacts on outcomes of these studies. METHODS: We searched six databases and five official websites to find the SRs of RFA versus HR for early HCC. The Overview Quality Assessment Questionnaire (OQAQ), the Cochrane Collaboration's tool, and modified MINORS score were applied to assess their quality for SRs, randomized (RCTs) and nonrandomized controlled trials (NRCTs), respectively. RESULTS: Nineteen SRs were included. The results showed that the overall quality was poor, with a mean OQAQ score of 3.3 and 95%CI 2.6 to 4.1, only five (26.3%) SRs were good quality, six (31.6%) misused the statistical models, and three of them changed outcome direction after modification. Five SRs taken retrospective studies as RCT. In addition, a total of 39 primary studies referenced by these 19 SRs were included. The results showed that 3 RCTs were leveled grade B, and 35 NRCTs were of moderate quality, with an estimated mean MINORS score of 15.0 and 95%CI 14.6 to 15.4. CONCLUSIONS: The overall quality of SRs comparing the effects between RFA and HR for early HCC was poor. There was high heterogeneity and low evidence level. Physicians should take caution when applying the results from these studies to their clinical practice.

The safety and effectiveness of Da Vinci surgical system compared with open surgery and laparoscopic surgery: a rapid assessment.

OBJECTIVE: The primary objectives of this rapid assessment were to assess the clinical evidence of Da Vinci surgical system (DVSS) comparing with open procedures and laparoscopic procedures, and in order to provide the evidence for health decision makers and clinician. METHODS: A comprehensive search of electronic databases (EMbase, PubMed, The Cochrane Library, Web of Science, CNKI, VIP, CBM and Wanfang) and HTA websites were completed up to 9 October, 2013. Two reviews (Jiajie Yu and Yingqiang Wang) independently extracted data of the manuscripts, and assessed quality of included studies using AMSTAR tools. Qualitative description and GRADE were used to report the outcomes and evidence quality. OUTCOMES: A total of 17 studies were included: 3 were HTA and 14 were SR/meta-analysis. The included studies focused on prostatectomy, nephrectomy, hysterectomy colorectal surgery, and cardiac surgery. DVSS was shown to be associated with statistically significant reduction in length of hospital stay, blood loss, and transfusion rate compared with open and laparoscopic surgery, but increase in operative time when compared with open surgery. CONCLUSION: Based on the evidence included in this rapid assessment, DVSS has a limited impact on several clinical outcomes. Considering no available data from randomized controlled trials and much higher cost, decisions will be complex and need to be made carefully. Decision makers should cut down the quantity of purchasing and reasonable allocate them.