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Sudden disease outbreaks may not necessarily reflect a recent pathogen introduction but may instead arise from the disruption of a host-pathogen equilibrium. Together with invasive species, emerging pathogens pose significant threats to biodiversity. The dynamics of each stressor have been studied separately, yet rarely when interacting. Using a 40-year dataset, we tested the hypothesis that the introduction of an invasive fish leads to such a disruption, manifested by ranavirosis outbreaks on amphibian hosts. MCP sequencing revealed the historical presence of two major Ranavirus clades, with low prevalence. The introduction of fish was not followed by the emergence of new viruses, but rather by an increase in the prevalence of the strains already present, fitting the ‘endemic pathogen hypothesis’. Two decades after the first die-offs, one amphibian species persists in extremely low numbers, but Ranavirus prevalence is closer to the enzootic phase that preceded the outbreaks. Models show that host population collapse and lack of recovery are best explained by the concerted interaction of Ranavirus and invasive fish. We provide robust evidence that invasive species can impact naïve communities by disrupting the host-pathogen balance, exacerbating health threats. This study emphasizes the importance of exploring the historical interactions between multiple stressors to understand population declines.

Greenery can affect spatial characteristics such as relationship between hard and soft surfaces and activities inside open spaces. Among different types of greenery, trees have influences on summer shading and winter solar access, and hence usage patterns in open spaces. However, the relationship between tree planting and open space characteristics such as typology, proportion and height-to-width ratio in terms of shading and solar access was rarely investigated. On the other hand, there has been an increasing number of studies on using parametric tools to design urban environment recently. Despite the success in urban fabric planning by parametric tools, the utilization of these tools to design open spaces with a relatively smaller scale has not been revealed. Even worse, parameters that should be included in a parametric design tool for open space planning are still unknown. Accordingly, the primary objective of this study is to, by investigating the design characteristics and concepts of different open spaces, identify parameters for a parametric tool to design green open spaces. Specifically, the possibility of using shaded areas projected by trees and surrounding buildings as one of the parameters will be revealed. The study also aims at examining how the height-to-width ratios, proportions and typologies of open spaces will affect tree planting positions when optimizing shading or solar access of the spaces in different climate zones. Results from this study will provide designers with an additional layer of information when designing open spaces.

A five-sentence letter published in the Journal in 1980 has been heavily cited as evidence that long-term opioid therapy has seldom been associated with addiction. Of the 608 citations, 72.2% used the letter uncritically as evidence that such addiction was rare.

Background. A single-nucleotide polymorphism (SNP), rs2268388, in the acetyl-coenzyme A carboxylase beta (ACACB) gene is associated with susceptibility to type 2 diabetic nephropathy (T2DN) in Japanese and European-American populations. Whether this association also exists in Chinese patients is unclear. Attempts at replication in small Singaporean and Korean samples were not significant.Methods. Eight ACACB SNPs were genotyped in 595 subjects with type 2 diabetes mellitus born in Hong Kong or southern China, 295 with advanced T2DN and 300 with long-standing diabetes lacking nephropathy. Association analyses were focused primarily on SNP rs2268388 and secondarily on flanking SNPs and haplotypes.Results. Adjusting for age, gender and diabetes duration, ACACB SNP rs2268388 was significantly associated with advanced T2DN (odds ratio=2.39; recessive model; P=0.0129).Conclusion. These results in the Chinese replicate the association between T2DN and rs2268388, as seen in Japanese and European Americans. The ACACB gene and attendant alterations in fatty acid oxidation may play important roles in susceptibility to T2DN. Targeting this pathway may provide novel treatment options for the prevention of diabetic nephropathy. © 2010 The Author. Published by Oxford University Press on behalf of ERA-EDTA. All rights reserved., link_to_OA_fulltext

This paper presents a method for automatic mould parting direction selection in computer-aided design of moulds and dies. When given a three-dimensional CAD model, the minimum volume bounding box of the model is found first. Three pairs of possible parting directions are defined based on the bounding box surface normal vectors. They are in the length direction, the width direction and the height direction of the bounding box. Now, a dexel model is constructed along each parting direction. Parting lines corresponding to the three possible parting directions are estimated using a slice method. Finally, criteria such as undercut, draw, projected area and flatness in all parting directions are quantified using the dexel model of the part. A designer's preferences, coded as fuzzy weighting factors, are set-up for the evaluation of the most promising parting direction. Uncertainty that is assumed to be inherent in the assessments of the ratings and weights is accounted for by the proposed fuzzy heuristic.

The nutritive composition of a hot aqueous extract of wild Ganoderma fruit bodies was determined. This extract was assessed for cytotoxicity and in vivo genotoxicity by both acute and subchronic exposure of mice (given by mouth at a dose equivalent to extract of 220g fresh Ganoderma fruit body/kg body weight). To test any alleged protection against mutagens by Ganoderma treatments, the mice were injected intraperitoneally with the radiomimetic mutagen ethyl methanesulfonate (EMS), and after 24hr of treatment their lymphocytes were examined using the comet assay. Ganoderma extract consisted of Folin-positive material (68.9% of dry weight), but protein comprised only 7.3% of dry weight. Glucose accounted for 11. 1% and metals 10.2% of dry weight (K, Mg and Ca being the major components with Ge (often touted as being of value in sales literature for Ganoderma preparations) having the fifth highest metal concentration at 489 microg/g). In comparison to rodent chow, Ganoderma extract was a modest dietary supplement. No evidence was found for genotoxic chromosomal breakage nor cytotoxic effects by Ganoderma extract in the mouse, nor did it protect against the effects of ethyl methanesulfonate. We found no support in this study for the extract having any value in protecting against the test mutagen.

The airway epithelium participates in chronic airway inflammation by expressing adhesion molecules that mediate the transmigration of neutrophils into the inflamed airways. We hypothesize that, in patients with bronchiectasis, cytokines in their bronchial secretions enhance the expression of intercellular cell adhesion molecule (ICAM-1) in the bronchial epithelium and thus contribute to sustained recruitment of neutrophils into the inflamed airways. In the present study, we investigated the effect of bronchial secretions on the regulation of ICAM-1 in bronchial epithelial cells, and its modulation by pharmacologic agents. The expression of ICAM-1 mRNA and protein in human bronchial epithelial cells upon exposure to sputum sol from subjects with bronchiectasis were evaluated by reverse transcription-polymerase chain reaction (RT-PCR) and ELISA, respectively. Modulating effects of dexamethasone, ibuprofen, MK-663 or triptolide on ICAM-1 regulation were investigated in vitro. We demonstrated that changes in ICAM-1 expression correlated with levels of TNF-alpha in the sputum sol, and treatment of sol samples with TNF-alpha antibodies attenuated both the increase in ICAM-1 mRNA and protein. The role of TNF-alpha was further demonstrated when TNF-alpha elicited dose dependent increase in ICAM-1 expression. The sputum effect could also be suppressed dose-dependently by pre-incubation of bronchial epithelial cells with dexamethasone, ibuprofen, MK-663 or triptolide. Evidence is thus provided for the upregulation of bronchial epithelial ICAM-1 expression by airway secretions in bronchiectasis and a specific role for TNF-alpha in the secretions. The success of drug attenuation of this upregulation provides insight into possible therapeutic paradigms in the management of the disease.

The present article describes a new method of microvessel dimensions measurement in which a writing oscilloscope is used to continuously and graphically record the microvessel video signal from television microscopy at a fast rate of 50 records per second. Dimensions of interest, such as the microvessel red blood cell flux diameter, are then easily marked out manually from the graphic records and a dynamic electrical signal proportional to the dimensions is generated. The signal is then recorded on one channel of a multichannel voltage recorder and is synchronised with other experimental signals which have previously been recorded on-line during the experiment. The result is that the dimension signal appears to have been recorded on-line during the experiment as well. This is desirable for electronic signal correlation and processing. This method is useful when poor experimental conditions, commonly encountered, make automatic recording of microvessel dimension unsatisfactory and manual inspection and processing become necessary.

A tibial lengthening apparatus has been developed which incorporates a distractive force measurement system. Lengthening is carried out generally in accordance with the 2-stage Anderson method. After closed percutaneous osteoclosis (clinically performed fracture), the tibial fragments are held in place by Steinmann pins and novel Steinmann pin-clamping blocks to ensure rigid fixation and accurate alignment. The blocks provide electrical insulation between the patient and the apparatus and are able to accommodate different sizes of Steinmann pins and misalignment of the pins as a result of their insertion in the tibia by drilling. A metric distraction mechanism provides controlled lengthening and the distractive force is sensed by two transducers, each consisting of an aluminium ring to which are bonded electrical resistance strain gauges in a full bridge configuration. Electronic instrumentation is used to process the transducer signals and the resulting force readings are displayed on a digital panel meter as well as being recorded on a digital printer.