Prevalence of Coxiella burnetii in western grey kangaroos (Macropus fuliginosus) in Western Australia

We investigated the role of the western grey kangaroo (Macropus fuliginosus) in the maintenance and transmission of Coxiella burnetii in Western Australia. Sera from 1,017 kangaroos were tested using an indirect enzyme-linked immunosorbent assay (ELISA) for the presence of C. burnetii antibodies. The overall antibody prevalence across 12 locations throughout mid- to southwestern Western Australia was 24.1% (95% CI: 21.6-26.8). Feces from 990 of the same animals were tested using PCR to identify active shedding of C. burnetii in excreta. Coxiella burnetii DNA was detected in 4.1% (95% CI: 3.1-5.6) of samples. Our results suggest that kangaroos are reservoirs for C. burnetii in Western Australia and may contribute to transmission of the organism to domestic livestock and humans.     

实时无标记细胞分析系统 (RTCA) 在药物心肌毒性检测和生物活性研究中的应用

实时无标记细胞分析系统 (Real time xCELLigence analysis system,RTCA) 是一种新型细胞检测技术,能够连续监测、记录及分析细胞活动产生的各种信息,在药物研究中的心肌毒性评估和细胞生物活性考察方面都可以发挥重要作用。文中首先对RTCA的原理与特点进行了介绍,然后分别对RTCA在心肌毒性和细胞生物活性研究中的应用现状进行了综述,为了解和使用RTCA提供了参考。RTCA技术具有实时无标记、非侵入性、高通量、准确性高等特点,不仅有助于药物研究和新药开发,在其他一些领域也有着广阔良好的应用前景。     

Sleep Disturbances and Health-Related Quality of Life in Adults with Steady-State Bronchiectasis

Background

Sleep disturbances are common in patients with chronic lung diseases, but little is known about the prevalence in patients with bronchiectasis. A cross sectional study was conducted to investigate the prevalence and determinants associated with sleep disturbances, and the correlation between sleep disturbances and quality of life (QoL) in adults with steady-state bronchiectasis.

Methods

One hundred and forty-four bronchiectasis patients and eighty healthy subjects were enrolled. Sleep disturbances, daytime sleepiness, and QoL were measured by utilizing the Pittsburgh Sleep Quality Index (PSQI), Epworth Sleepiness Scale (ESS) and St. George Respiratory Questionnaire (SGRQ), respectively. Demographic, clinical indices, radiology, spirometry, bacteriology, anxiety and depression were also assessed.

Results

Adults with steady-state bronchiectasis had a higher prevalence of sleep disturbances (PSQI>5) (57% vs. 29%, P<0.001), but not daytime sleepiness (ESS≥10) (32% vs. 30%, P = 0.76), compared with healthy subjects. In the multivariate model, determinants associated with sleep disturbances in bronchiectasis patients included depression (OR, 10.09; 95% CI, 3.46–29.37; P<0.001), nocturnal cough (OR, 1.89; 95% CI, 1.13–3.18; P = 0.016), aging (OR, 1.04; 95% CI, 1.01–1.07; P = 0.009) and increased 24-hour sputum volume (OR, 2.01; 95% CI, 1.22–3.33; P = 0.006). Patients with sleep disturbances had more significantly impaired QoL affecting all domains than those without. Only 6.2% of patients reported using a sleep medication at least weekly.

Conclusions

In adults with steady-state bronchiectasis, sleep disturbances are more common than in healthy subjects and are related to poorer QoL. Determinants associated with sleep disturbances include depression, aging, nighttime cough and increased sputum volume. Assessment and intervention of sleep disturbances are warranted and may improve QoL.     

Middle‐Late Ordovician iron‐rich nodules on Yangtze Platform,South China,and their palaeoenvironmental implications

Iron‐rich nodules occur on the Yangtze Platform, South China, especially along the marginal area, during the late Middle and early Late Ordovician (Darriwilian–Sandbian). Based on the study of samples from the Daling section, Anhui Province, these nodules include: (1) oncoids; (2) coated bioclasts; and (3) coated micritic intraclasts, all of which potentially have a similar biological origin. The nodule‐bearing strata were deposited in a midouter ramp setting, indicating sediment starvation and open marine conditions, possibly combined with anoxia in deeper basinal areas and cool water upwelling during the formation of the nodules, rather than terrestrial input or local tectonic movement. The widespread distribution of iron‐rich nodules at this time was probably favoured by high sea level and cooling climate, conditions that simultaneously favoured the evolutionary radiations of the GOBE in South China. Thus, these nodules form a time‐specific signature of a critical time in the evolution of the marine ecosystem in the context of local environmental background along the marginal Yangtze Platform.     

The transport kinetics of lanthanide species in a single erythrocyte probed by confocal laser scanning microscopy

 A novel method has been developed to visualize and follow the temporal course of lanthanide transport across the membrane into a single living erythrocyte. By means of confocal scanning microscopy and the optical section technique, the entry of lanthanide ions was followed by the fluorescence quenching of fluorescein isothiocyanate (FITC)-labeled membrane and cytosol. From the difference of the quenching kinetics of the whole section and the central area, the time for diffusion through the membrane and the diffusion in the extracellular and intracellular media can be deduced. To clarify the mechanism of lanthanide-induced fluorescence quenching of FITC-labeled erythrocytes and to ensure that this reaction can be used in this method, the reaction was investigated by steady-state fluorescence techniques. The results showed that the lanthanides strongly quenched the florescence emitted by FITC covalently bound to membrane proteins and cytosolic proteins. The static quenching mechanism is responsible for the fluorescence quenching of FITC-labeled proteins by Ln species. The quenching mechanism is discussed on the basis of complex formation. The dependence of fluorescence quenching on both ion size and the total orbital angular momentum L supports the complexation mechanism. The transport time across the membrane is strikingly correlated with Ln species and extracellular concentration. For a given concentration, the transport time of [Ln(cit)₂]^3– is much shorter than that of Ln³⁺, since they enter the cells via the anion channel. This is supported by the inhibition effect of 4,4′-diisothiocyanato-2,2′-stilbenendisulfonate on the transport of [Ln(cit)₂]^3–. On the other hand, the transport of free Ln³⁺ might be attributed to the enhanced permeability of erythrocytes owing to Ln³⁺ binding. These findings strongly demonstrate the existence of the non-internalization mechanism of Ln species uptake by erythrocytes. Received: 7 January 1999 / Accepted: 7 May 1999     

Design and <Emphasis Type="Italic">In Vitro</Emphasis> Evaluation of Capsaicin Transdermal Controlled Release Cubic Phase Gels

The purpose of this study was to design and investigate the transdermal controlled release cubic phase gels containing capsaicin using glycerol monooleate (MO), propylene glycol (1,2-propanediol, PG), and water. Three types of cubic phase gels were designed based on the ternary phase diagram of the MO–PG–water system, and their internal structures were confirmed by polarizing light microscopy (PLM) and small-angle X-ray scattering (SAXS). Release results showed the cubic phase gels could provide a sustained system for capsaicin, while the initial water content in the gels was the major factor affecting the release rate. Release kinetics was determined to fit Higuchi’s square-root equation indicating that the release was under diffusion control. The calculated diffusion exponent showed the release from cubic phase gels was anomalous transport. The unique structure of the cubic phases, capsaicin distributed in the lipid bilayers, and cubic phase gel swelling contributed to the release mechanism. The cubic phase gel may be an interesting application for transdermal delivery system of capsaicin in alleviating the post-incision pain.     

Prevalence of Cryptosporidium species in recreational versus non-recreational water sources

Cryptosporidiosis, caused by the protozoan parasite Cryptosporidium, represents the major public health concern of water utilities in developed nations due to its small size, resistance to disinfection and ability to be shed in large numbers in faeces. In Australia, recreational access is not allowed on direct supply sources, however, in Western Australia, limited recreational access to drinking water catchments has been allowed, although only in the outer catchment. Recreational activities within 2 km of the drinking water body is prohibited. The present study compared the amount, prevalence and species of Cryptosporidium in recreational versus non-recreational water catchments in the south west of Western Australia (WA). Recreational water catchments, which allowed swimming and camping had a higher prevalence of Cryptosporidium and the majority of samples were the human-associated C. hominis. Non-recreational catchments had a lower prevalence and all the samples genotyped were C. parvum. Risk analysis identified increasing population as strongly correlated with an increase in the prevalence of Cryptosporidium in recreational catchments. This suggests that recreational access to drinking water catchments is a serious public health risk and government policy limiting activities to the outer catchment should be supported.     

Molecular characterization of Eimeria species in macropods

A total of 597 faecal samples were collected from western grey kangaroos (Macropus fuliginosus), Euros (M. robustus), red kangaroos (M. rufus) in Western Australia and Eastern Grey Kangaroos (M. giganteus) from Victoria and screened for the presence of Eimeria by PCR at the 18S ribosomal RNA (rRNA) locus. The overall prevalence was 24.3% (145/597). At the 18S rRNA locus, sequences were obtained for 25 of the 145 positives. Phylogenetic analysis indicated that all the macropod-derived Eimeria species grouped in a separate marsupial clade that included Eimeria trichosuri from brushtail possums. At least 6 different clades were identified within the marsupial isolates and many of the genotypes identified are likely to be valid species, however morphological and biological data need to be collected to match sequences to previously characterized Eimeria species or identify if they are new species.     

Performance of a pilot-scale submerged membrane bioreactor (MBR) in treating bathing wastewater

Bathing wastewater was treated by a pilot-scale submerged membrane bioreactor (MBR) for more than 60 days. The results showed that the removal rates of main pollutants of wastewater such as COD(Cr), LAS, NH(4)(+)-N and total nitrogen (TN) were above 93%, 99%, 99%, and 90%, respectively. The results of denaturing gel gradient electrophoresis (DGGE) and fluorescent in situ hybridization (FISH) indicated that the bacteria were stable. The abundant nitrobacteria intercepted by the membrane led to the high removal rate of ammonia and TN. FISH and 16S rDNA gene sequence analysis revealed that some specific phylogenetic group of bacteria, the Pseudomonas sp. Ochrobactrum anthropi sp. and Enterobacter sp. probably played a major role in the development of the mature biofilms, which led to the severe irreversible membrane biofouling.