Floristics of Higher Plants in China——Report from Catalogue of Life: Higher Plants in China Database

Biodiversity research increasingly relies on distribution networks for dealing with large-scale primary data. Up-to-date information on biodiversity is critical for the proper management and conservation of any area. The first step towards conservation should be to compile an authoritative species inventory or checklist. Catalogue of Life: Higher Plants in China (CNPC) is an ongoing biodiversity informatics project with the aim to integrate existing higher plants inventory data, and provide access via an internet based web service to public user and the scientific community. The CNPC, for the first time, provides integrated and authoritative taxonomic information on higher plant species found in China, and this database will be permanent, free and continously updated. Presently, a total of 34377 species have been included in the database. Among of them, 16620 species are only found in China. Taxa are classified into 432 families and 3941 genera. The CNPC will be an important source for scientists working on Chinese flora, and will play an important role in helping to achieve the targets set under the Global Strategy for Plant Conservation in the future.     

Ecophysiological Response of Plants to Combined Pollution from Heavy-duty Vehicles and Industrial Emissions in Higher Humidity

Pollution can be aggravated in industrial areas if traffic exhausts are mixed with industrial emissions under high humidity conditions. Plants growing in such environments may suffer from severe stress. The impact of vehicle emissions on urban vegetation in an industrial area in Qingdao, China, was investigated by studying seven plant species at visible, physiological and chemical levels. The traits of plant species in certain environmental conditions were compared between a clear area, Badaguan (BDG), and polluted area, Roadside (RS). We found that foliar sulfur uptake for all species was not significantly high at RS compared with BDG, although the sulfur content of atmosphere and surface soils at RS were much higher than those at BDG. For Ailanthus altissima Swingle, the content of foliar pigment and net photosynthesis rate (PN) decreased by 20%. Meanwhile, leaves became incrassate and no visible leaf damage was noted, suggesting this species could adapt well to pollution. A 50% decrease in PN occurred in Hibiscus syriacus L., but there was no statistical change in content of chlorophyll a and b and water uptake. Also, thickened leaves may prevent the pollutant from permeation. Foliar water content was still at a low level, although a water compensation mechanism was established for Fraxinus chinensis Rosb. reflected by low water potential and high water use efficiency. More adversely, a 65% decrease in PN happened inevitably with the significant decomposition of photosynthetic pigments, which exhibited visible damage. We also noted in one evergreen species (Magnolia grandiflora L.) that water absorption driven by low water potential should be helpful to supply water loss induced by strong stomatal transpiration and maintain normal growth. Furthermore, photosynthetic pigment content did not decline statistically, but supported a stable net assimilation. Two herbaceous species, Poa annua L. and Ophiopogon japonicus Ker‐Gawl., were very tolerant to adverse stress compared to other woody species, especially in assimilation through a compensatory increase in leaf area. A more remarkable decline in PN (decrease 80%) was noted in the exotic but widespread species, Platanus orientalis L., with serious etiolation and withering being exhibited on the whole canopy. Our results suggested, special for woody species, that most native species are more tolerant to pollution and therefore should to be broadly used in a humid urban industrial environment with heavy‐duty vehicle emissions. (Managing editor: Ya‐Qin Han)     

Evolution of Socioeconomic Conditions and Its Relation to Spatial–Temporal Changes of Giardiasis and Helminthiasis in Amazonian Children

EcoHealth - This study analyzed the evolution of socioeconomic, sanitary, and personal factors as well as spatiotemporal changes in the prevalence of helminthiasis and giardiasis in urban Amazonian...     

The Patterns of Secretory Structure and Their Relation to Hypericin Content in Hypericum

金丝桃属植物分泌结构的类型和金丝桃素含量的相关性 吕洪飞^1,2 沈宗根¹ 李景原¹ 胡正海^1**     

Clonal Growth in Plants in Relation to Resource Heterogeneity:Foraging Behavior

In nature, essential resources for organisms, such as food for animals and light, water and nutrients for plants, are usually heterogeneously distributed, even at very small scale. As a result, all organisms, particularly plants mostly sessile, have a difficulty in acquiring essential resources from their environments. Animals express various types of foraging behavior to capture heterogeneously distributed essential foods. Clonal growth ( a vegetative reproductive process where by more than one individual of identical genetic composition is formed ) provides clonal plant not only with many "mouths" at different spatial positions, but also with a large spacial movability. As a clonal plant grows in environments characterized by a small-scale resource heterogeneity, its inter ramet connection permits a resource-sharing among the connected tamers. In addition, it may also allow certain ramets to respond locally and non-locally to resousce heterogeneity. This may lead to a division of labor among the connected ramets and a selective placement of ramets in favorable micro-habitats. Together these may enhance exploitation of resource heterogeneity by clonal plants, and in turn greatly contribute to maintenance or improvement of fitness. Such a behavior of clonal plants, expressed in heterogeneous environments, is to a large extent comparable to that of animals. Therefore, it has been considered as foraging behavior in clonal plants. More recently, it has been observed that phenotypic plasticity of clonal plants, which is relevant to foraging behavior, varies among species, types of genet architecture as well as among types of plants habitats. Foraging in clonal plants and its diversity have been receiving increasingly intensive investigations.     

The Final Size of an Epidemic and Its Relation to the Basic Reproduction Number

We study the final size equation for an epidemic in a subdivided population with general mixing patterns among subgroups. The equation is determined by a matrix with the same spectrum as the next generation matrix and it exhibits a threshold controlled by the common dominant eigenvalue, the basic reproduction number R₀{\mathcal{R}_{0}}: There is a unique positive solution giving the size of the epidemic if and only if R₀{\mathcal{R}_{0}} exceeds unity. When mixing heterogeneities arise only from variation in contact rates and proportionate mixing, the final size of the epidemic in a heterogeneously mixing population is always smaller than that in a homogeneously mixing population with the same basic reproduction number R₀{\mathcal{R}_{0}}. For other mixing patterns, the relation may be reversed.     

Open and Closed： The Roles of Linker Histones in Plants and Animals

Histones package DNA in all eukaryotes and play key roles in regulating gene expression. Approximately 150 base pairs of DNA wraps around an octamer of core histones to form the nucleosome, the basic unit of chromatin. Linker histones compact chromatin further by binding to and neutralizing the charge of the DNA between nucleosomes. It is well established that chromatin packing is regulated by a complex pattern of posttranslational modifications （PTMs） to core histones, but linker histone function is less well understood. In this review, we describe the current understand- ing of the many roles that linker histones play in cellular processes, including gene regulation, cell division, and devel- opment, while putting the linker histone in the context of other nuclear proteins. Although intriguing roles for plant linker histones are beginning to emerge, much of our current understanding comes from work in animal systems. Many unanswered questions remain and additional work is required to fully elucidate the complex processes mediated by linker histones in plants.     

The Primary Resistance of Helicobacter pylori in Taiwan after the National Policy to Restrict Antibiotic Consumption and Its Relation to Virulence Factors—A Nationwide Study

Objective

The Taiwan Government issued a policy to restrict antimicrobial usage since 2001. We aimed to assess the changes in the antibiotic consumption and the primary resistance of H. pylori after this policy and the impact of virulence factors on resistance.

Methods

The defined daily dose (DDD) of antibiotics was analyzed using the Taiwan National Health Insurance (NHI) research database. H. pylori strains isolated from treatment naïve (N=1395) and failure from prior eradication therapies (N=360) from 9 hospitals between 2000 and 2012 were used for analysis. The minimum inhibitory concentration was determined by agar dilution test. Genotyping for CagA and VacA was determined by PCR method.

Results

The DDD per 1000 persons per day of macrolides reduced from 1.12 in 1997 to 0.19 in 2008, whereas that of fluoroquinolones increased from 0.12 in 1997 to 0.35 in 2008. The primary resistance of amoxicillin, clarithromycin, metronidazole, and tetracycline remained as low as 2.2%, 7.9%, 23.7%, and 1.9% respectively. However, the primary levofloxacin resistance rose from 4.9% in 2000–2007 to 8.3% in 2008–2010 and 13.4% in 2011–2012 (p=0.001). The primary resistance of metronidazole was higher in females than males (33.1% vs. 18.8%, p<0.001), which was probably attributed to the higher consumption of nitroimidazole. Neither CagA nor VacA was associated with antibiotic resistance.

Conclusions

The low primary clarithromycin and metronidazole resistance of H. pylori in Taiwan might be attributed to the reduced consumption of macrolides and nitroimidazole after the national policy to restrict antimicrobial usage. Yet, further strategies are needed to restrict the consumption of fluoroquinolones in the face of rising levofloxacin resistance.     

The Problem of Colliding Networks and its Relation to Cell Fusion and?Cancer

Cell fusion, a process that merges two or more cells into one, is required for normal development and has been explored as a tool for stem cell therapy. It has also been proposed that cell fusion causes cancer and contributes to its progression. These functions rely on a poorly understood ability of cell fusion to create new cell types. We suggest that this ability can be understood by considering cells as attractor networks whose basic property is to adopt a set of distinct, stable, self-maintaining states called attractors. According to this view, fusion of two cell types is a collision of two networks that have adopted distinct attractors. To learn how these networks reach a consensus, we model cell fusion computationally. To do so, we simulate patterns of gene activities using a formalism developed to simulate patterns of memory in neural networks. We find that the hybrid networks can assume attractors that are unrelated to parental attractors, implying that cell fusion can create new cell types by nearly instantaneously moving cells between attractors. We also show that hybrid networks are prone to assume spurious attractors, which are emergent and sporadic network states. This finding means that cell fusion can produce abnormal cell types, including cancerous types, by placing cells into normally inaccessible spurious states. Finally, we suggest that the problem of colliding networks has general significance in many processes represented by attractor networks, including biological, social, and political phenomena.     

SEROTONIN—Its Possible Relation to Allergic Disease

Increased amounts of serotonin as well as histamine have been found in the blood of animals during anaphylactic shock. Certain animals, particularly those in which antihistamines do not prevent anaphylaxis, have been found to have increased quantities of serotonin in the lung tissue during anaphylactic shock.Serotonin is a chemical derived from the amino acid tryptophan, which is widely distributed. It is excreted in the urine as the metabolite 5-hydroxyindoleacetic acid. Serotonin has been found in increased amounts in the blood of patients with carcinoids. The increase of serotonin in the blood and the finding of the excretory product in the urine has become a corroborative sign of the disease. The involvement of serotonin in the production of mental disease is evidenced by the effect of serotonin antagonists, which appear to influence mental behavior.That serotonin antagonists may be of ultimate value in the treatment of allergic disease is a possibility to be considered.     

Long-distance ABA Signaling and Its Relation to Other Signaling Pathways in the Detection of Soil Drying and the Mediation of the Plant’s Response to Drought

In this article we review evidence for a variety of long-distance signaling pathways involving hormones and nutrient ions moving in the xylem sap. We argue that ABA has a central role to play, at least in root-to-shoot drought stress signaling and the regulation of functioning, growth, and development of plants in drying soil. We also stress the importance of changes in the pH of the leaf cell apoplast as influenced both by edaphic and climatic variation, as a regulator of shoot growth and functioning, and we show how changes in xylem and apoplastic pH can affect the way in which ABA regulates stomatal behavior and growth. The sensitivity to drought of the pH/ABA sensing and signaling mechanism is emphasized. This allows regulation of plant growth, development and functioning, and particularly shoot water status, as distinct from stress lesions in growth and other processes as a reaction to perturbations such as soil drying.     

The Biosynthesis of δ-Aminolevulinic Acid in Chlorella

When autotrophically growing cultures of Chlorella are treated with levulinic acid, delta-aminolevulinic acid is excreted into the medium, providing a direct demonstration of alpha-aminolevulinic acid production in a green plant. Evidence is presented which indicates that alpha-aminolevulinic acid formation may be the the rate-controlling step of chlorophyll synthesis in Chlorella, and that control of the rate of alpha-aminolevulinic acid synthesis may be exerted at the level of production and breakdown of an enzyme which catalyzes its formation.     

Induction of Rat Prolactinoma by β－Estradiol and Its Relation to Expression of c－myc Oncogene

ＩｎｄｕｃｔｉｏｎｏｆＲａｔＰｒｏｌａｃｔｉｎｏｍａｂｙβ－ＥｓｔｒａｄｉｏｌａｎｄＩｔｓＲｅｌａｔｉｏｎｔｏＥｘｐｒｅｓｓｉｏｎｏｆｃ－ｍｙｃＯｎｃｏｇｅｎｅ￥ＸＵＲｏｎｇ－ｋｕｎ（许荣琨）；ＧＵＯＣｈｕａｎ－ｈａｉ（郭传海）；ＨＵＡＮＧＭａｎ－ｙ...     

Circadian Rhythmicity of Acid Secretion and Electrical Function in Intact and Injured Rat Gastric Mucosa—The Relation of Timing to Ulcerogenesis

Alteration of electrical function in mammalian gastric mucosa is considered as an indicator of gastric barrier rupture. Measurements of transmucosal potential difference (PD) and electrical resistance (R) have documented such alterations to a variety of mucosal damaging agents. This study was designed to test whether the rat gastric mucosa exhibits circadian rhythms in acid secretion and electrical function and whether the damage produced by a mucosal acting agent (butyric acid) is also circadian-stage dependent. Mucosa was isolated from the gastric body of male rats standardized from birth to a light-dark regimen. Circadian rhythms of acid secretion and PD and R with acrophases during the dark hours were documented. Administration of butyric acid produced circadian-stage dependent damage with an acrophase also during the dark-phase span. Thus, in this experimental model, measurements of electrical function represented a poor index of gastric mucosal susceptibility to damaging agents. The authors discuss the possibility that rhythms other than those related to electrical function may better define mucosal vulnerability to ulcerogenesis.