Isolation and screening of indigenous microalgae species for domestic and livestock wastewater treatment, biodiesel production, and carbon sequestration

The use of indigenous microalgae strains for locally generated domestic (DWW) and livestock wastewater (LWW) treatment is essential for effective and economical applications. Phototrophic microalgae-based biofuel production also contributes to carbon sequestration via CO₂ fixation. However, simultaneous consideration of both isolation and screening procedures for locally collected indigenous microalgae strains is not common in the literature. We aimed to isolate indigenous microalgae strains from locally collected samples on coastlines and islands in South Korea. Among five isolated strains, Chlorella sorokiniana JD1-1 was selected for DWW and LWW treatment due to its ability to grow in waste resources. This strain showed a higher specific growth rate in DWW than artificial growth medium (BG-11) with a range of 0.137-0.154 d^-1. During cultivation, 96.5%-97.1% of total nitrogen in DWW and 89.2% in LWW was removed. Over 99% of total phosphorus in DWW and 96.4% in LWW was also removed. Finally, isolated C. sorokiniana JD1-1 was able to fix CO₂ within a range of 0.0646-0.1043 g CO₂ L^-1 d^-1. These results support the domestic applications of carbon sequestration-efficient microalgae in the waste-to-energy nexus.

Manipulation of Unfrozen Water Retention for Enhancing Petroleum Hydrocarbon Biodegradation in Seasonally Freezing and Frozen Soil

Manipulating the retention of unfrozen water in freezing contaminated soil to achieve prolonged bioremediation in cold climates remains unformulated. This freezing-induced biodegradation experiment shows how nutrient and zeolite amendments affect unfrozen water retention and hydrocarbon biodegradation in field-aged, petroleum-contaminated soils undergoing seasonal freezing. During soil freezing at a site-specific rate (4 to -10 °C and -0.2 °C/d), the effect of nutrients was predominant during early freezing (4 to -5 °C), alleviating the abrupt soil-freezing stress near the freezing-point depressions, elevating alkB1 gene-harboring populations, and enhancing hydrocarbon biodegradation. Subsequently, the effect of increased unfrozen water retention associated with added zeolite surface areas was critical in extending hydrocarbon biodegradation to the frozen phase (-5 to -10 °C). A series of soil-freezing characteristic curves with empirical α-values (soil-freezing index) were constructed for the tested soils and shown alongside representative curves for clays to sands, indicating correlations between α-values and nutrient concentrations (soil electrical conductivity), zeolite addition (surface area), and hydrocarbon biodegradation. Heavier hydrocarbons (F3: C16-C34) notably biodegraded in all treated soils (22-37% removal), as confirmed by biomarker-based analyses (17α(H),21β(H)-hopane), whereas lighter hydrocarbons were not biodegraded. Below 0 °C, finer-grained soils (high α-values) can be biostimulated more readily than coarser-grained soils (low α-values).

Characteristics of long-term changes in microbial communities from contaminated sediments along the west coast of South Korea: Ecological assessment with eDNA and physicochemical analyses

The environmental DNA (eDNA) metabarcoding was applied to assess benthic ecological health in the west coast of South Korea by investigating a long-term microbial community change (2015-17). The ecological interaction among microorganisms, from phylum to family level, and their associations to environmental variables across the five regions were highlighted. As part of the study, the available chemistry and toxicological data in the regions during the monitoring periods were incorporated into an integrated sediment triad assessment. The bacterial communities were dominated by Proteobacteria (34.2%), Bacteroidetes (13.8%), and Firmicutes (10.8%). Proteobacteria and Bacteroidetes dominated consistently across regions and years, while Firmicutes and Cyanobacteria significantly varied by region and years (p < 0.05). The abundance of this phylum declined over time with the increasing abundance of Cyanobacteria, indicating their independent interactions to certain environmental changes. Planctomycetes and Gemmatimonadetes linked to some contaminants (ΣPAHs and Cu), implying indicator taxa. Overall, eDNA-based microbial community analysis combined with exposures of contaminants and responses of microorganisms is a promising strategy for the assessment of benthic ecological health in contaminated sediments from coastal waters.

Integrated assessment of west coast of South Korea by use of benthic bacterial community structure as determined by eDNA, concentrations of contaminants, and in vitro bioassays

During the past few decades, contamination of sediments by persistent toxic substances (PTSs) has been observed in estuarine and coastal areas on the west coast of South Korea. The contaminants are suspected to cause toxicities in aquatic biota, but little is known about their ecological effects, particularly on benthic microbial communities. In this study, an eDNA-based assessment was applied along with classic assessments of exposure, such as chemistry and in vitro bioassays, to evaluate condition of benthic bacterial communities subjected to PTSs. Two strategies were adopted for the study. One was to conduct a comprehensive assessment in space (by comparing seawater and freshwater sites at five coastal regions) and in time (by following change over a 5-y period). Although we found that bacterial composition varied among and within years, some phyla, such as Proteobacteria (28.7%), Actinobacteria (13.1%), Firmicutes (12.7%), and Chloroflexi (12.5%) were consistently dominated across the study regions. Certain bacterial groups, such as Firmicutes and Verrucomicrobia have been linked to contamination at some sites in the study area and at specific points in time. Bacterial communities were not significantly correlated with salinity or AhR- and ER-mediated potencies, whereas concentrations of PAHs, APs, and certain metals (Cd and Hg) exhibited significant associations to the structure of bacterial communities at the phylum level. In fact, the relative abundance of microbes in the phylum Planctomycetes was significantly and negatively correlated with concentrations of PAHs and metals. Thus, the relative abundance of Planctomycetes could be used as an indicator of sedimentary contamination by PAHs and/or metals. Based on our correlation analyses, Cd and ER-mediated potencies were associated more with bacterial abundances at the class taxonomic level than were other PTSs and metals. Overall, the eDNA-based assessment was useful by augmenting more traditional measures of exposure and responses in a sediment triad approach and has potential as a more rapid screening tool.

Recovery of the benthic bacterial community in coastal abandoned saltern requires over 35 years: A comparative case study in the Yellow Sea

Salt is an essential nutrient for humans, and salterns exist worldwide. Although the construction of salterns has stopped and typical salterns are now mostly abandoned, there has been no research on the ecological recovery of the abandoned salterns. Here, we analyzed the bacterial diversity and community structure in three pairs of abandoned salterns that have undergone 1-35 years of natural restoration and tidal flats to determine the recovery time and process. Partial 16S rRNA sequences were amplified and sequenced to investigate the biodiversity and structure of the bacterial community in sediments collected from abandoned salterns and adjacent natural tidal flats (viz., controls) in the Yellow Sea. The most abundant microorganisms across locations were found to be members of Proteobacteria, ranging from 45 to 72%, which was also a crucial taxon in the bacterial recovery process. The benthic bacterial community of the salterns showed time-dependent recovery, as demonstrated by the similarity between the salterns and controls. Indeed, dissimilarities between bacterial communities were significant for the saltern that had been abandoned for one year, according to ANOSIM (R = 1.0, p < 0.01). The genera that were determined to contribute to the dissimilarity exhibited a significant correlation with the sedimentary phosphorus concentration. The dataset generally supported that the indigenous benthic bacterial community in an altered marine environment might require a considerable time to return to a natural status. Meanwhile, a delay between the recovery of the physicochemical environment and biological component was evidenced, which seemed to influence the recovery time in a site-specific manner. Overall, the present study provided new insight and understanding of the recovery of the benthic bacterial community in abandoned salterns in terms of recovery time and the associated process.

Multiple evaluation of the potential toxic effects of sediments and biota collected from an oil-polluted area around Abu Ali Island, Saudi Arabia, Arabian Gulf

After the Gulf War Oil Spill, there have been many investigations about distributions of oil-derived pollutants nearby areas, but lacking in ecotoxicological assessment. We evaluated the potential toxicity of asphalt mats, sediments, and biota (polychaetes, chitons, snapping shrimps, and crabs) by combining two bioassays (H4IIE-luc and Vibrio fischeri) and in situ microbial community (eDNA). Samples were collected from Abu Ali Island, and organic extracts were bioassayed and further fractionated according to the chemical polarity using silica gel column. Great aryl hydrocarbon receptor (AhR)-mediated potencies and inhibition of bioluminescence were mainly found in aromatics (F2) and saturates (F1) fractions of asphalt mat and sediments, respectively, while great toxicological responses in biota samples were found in resins and polar (F3) fraction. We also confirmed that potential toxicities of biota were species-specific; great AhR-mediated potencies were found in polychaetes and great bioluminescence inhibitions were found in crabs. In microbial communities, most genera (up to 90%) were associated with polycyclic aromatic hydrocarbons (PAHs)-degrading bacteria, supporting that PAHs are the primary stressors of the benthic community around Abu Ali Island. The present study provides useful information on the contamination status, risk assessment of environmental matrices and benthic organisms in Abu Ali Island.

Physical activity during pregnancy is associated with a lower prevalence of gestational diabetes mellitus in Vietnam

AIMS

To assess the association between physical activity (PA) during pregnancy and the prevalence of gestational diabetes mellitus (GDM) accounting for sitting time.

METHODS

The study used data from a cohort study of 2030 pregnant women in Vietnam. Women were recruited from six hospitals in Ha Noi, Hai Phong, and Ho Chi Minh City. Baseline measurements including PA and GDM were taken at 24-28 weeks of gestation. PA was assessed during the past 3 months before the interview using the interviewer-administered Pregnancy Physical Activity Questionnaire. GDM was diagnosed at 24-28 weeks of gestation using the 2013 World Health Organization criteria.

RESULTS

1987 out of 2030 pregnant women were included in the final analysis, of which 432 had GDM (21.7%). Women undertaking the highest level (upper tertile) of PA during pregnancy appeared to have a lower risk of GDM [odds ratio (OR) 0.70, 95% confidence interval (CI) 0.53-0.94, P_trend 0.017] when compared to those at the lowest tertile of PA. Similarly, women with increased levels of moderate-intensive activity and household/caregiving activity during pregnancy were associated with reduced risks of GDM (OR 0.66, 95% CI 0.50-0.86, P_trend 0.002 and OR 0.72, 95% CI 0.55-0.95, P_trend 0.020, respectively). These apparent inverse associations were not attenuated by their sitting time. There were no significant associations between sitting time, light-intensity activity, vigorous-intensity activity, occupation, sports/exercise, commuting, or meeting exercise guidelines and GDM risk.

CONCLUSIONS

High levels of PA, particularly moderate-intensity and household/caregiving activities during pregnancy were associated with a lower prevalence of GDM independent of sitting time.

Microbial community composition and PAHs removal potential of indigenous bacteria in oil contaminated sediment of Taean coast, Korea

The tidal flats near Sinduri beach in Taean, Korea, have been severely contaminated by heavy crude oils due to the Korea's worst oil spill accident, say the Hebei Spirit Oil Spill, in 2007. Crude oil compounds, including polycyclic aromatic hydrocarbons (PAHs), pose significant environmental damages due to their wide distribution, persistence, high toxicity, mutagenicity, and carcinogenicity. Microbial community of Sinduri beach sediments samples was analyzed by metagenomic data with 16S rRNA gene amplicons. Three phyla (Proteobacteria, Firmicutes, and Bacteroidetes) accounted for approximately ≥93.0% of the total phyla based on metagenomic analysis. Proteobacteria was the dominant phylum in Sinduri beach sediments. Cultivable bacteria were isolated from PAH-enriched cultures, and bacterial diversity was investigated through performing culture characterization followed by molecular biology methods. Sixty-seven isolates were obtained, comprising representatives of Actinobacteria, Firmicutes, α- and γ-Proteobacteria, and Bacteroidetes. PAH catabolism genes, such as naphthalene dioxygenase (NDO) and aromatic ring hydroxylating dioxygenase (ARHDO), were used as genetic markers to assess biodegradation of PAHs in the cultivable bacteria. The ability to degrade PAHs was demonstrated by monitoring the removal of PAHs using a gas chromatography mass spectrometer. Overall, various PAH-degrading bacteria were widely present in Sinduri beach sediments and generally reflected the restored microbial community. Among them, Cobetia marina, Rhodococcus soli, and Pseudoalteromonas agarivorans were found to be significant in degradation of PAHs. This large collection of PAH-degrading strains represents a valuable resource for studies investigating mechanisms of PAH degradation and bioremediation in oil contaminated coastal environment, elsewhere.

Enhanced bioremediation of nutrient-amended, petroleum hydrocarbon-contaminated soils over a cold-climate winter: The rate and extent of hydrocarbon biodegradation and microbial response in a pilot-scale biopile subjected to natural seasonal freeze-thaw temperatures

A pilot-scale biopile field experiment for nutrient-amended petroleum-contaminated fine-grained soils was performed over the winter at a cold-climate site. The rate and extent of hydrocarbon biodegradation and microbial responses were determined and corresponded to the on-site soil phase changes (from unfrozen to partially frozen, deeply frozen, and thawed) associated with natural seasonal freeze-thaw conditions. Treated and untreated biopiles were constructed (~3500kg each) on an open outdoor surface at a remediation facility in Saskatoon, Canada. The treated biopile received N-P-K-based nutrient and humate amendments before seasonal freezing. Real-time field monitoring indicated significant unfrozen water content in the treated and untreated biopiles throughout the freezing period, from the middle of November to early March. Unfrozen water was slightly more available in the treated biopile due to the aqueous nutrient supply. Soil CO₂ production and O₂ consumption in the treated biopile were generally greater than in the untreated biopile. Total removal percentages for F2 (>C10-C16), F3 (>C16-C34), and total petroleum hydrocarbons (TPH) in the treated biopile were 57, 58, and 58%, respectively, of which 26, 39, and 33% were removed during seasonal freezing and early thawing between November to early March. F3 degradation largely occurred during freezing while F2 hydrocarbons were primarily removed during thawing. Biomarker-based hydrocarbon analyses confirmed enhanced biodegradation in the treated biopile during freezing. The soil treatment increased the first-order rate constants for F2, F3, and TPH degradation by a factor of 2 to 7 compared to the untreated biopile. Shifts in bacterial community appeared in both biopiles as the biopile soils seasonally froze and thawed. Increased alkB1 gene copy numbers in the treated biopile, especially in the partially thawed phase during early thawing, suggest extended hydrocarbon biodegradation to the seasonal freeze-thaw season, due to the nutrients supplied prior to seasonal freezing.

Soyfood and isoflavone intake and risk of type 2 diabetes in Vietnamese adults

BACKGROUND/OBJECTIVES

Animal studies have demonstrated that soy isoflavones exert antidiabetic effects. However, evidence regarding the association between soyfood intake, a unique source of isoflavones, and type 2 diabetes remains inconclusive. This study assessed the relationship between habitual intakes of soyfoods and major isoflavones and risk of type 2 diabetes in Vietnamese adults.

SUBJECTS/METHODS

A hospital-based case-control study was conducted in Vietnam during 2013-2015. A total of 599 newly diagnosed diabetic cases (age 40-65 years) and 599 hospital-based controls, frequency matched by age and sex, were recruited in Hanoi, capital city of Vietnam. Information on frequency and quantity of soyfood and isoflavone intake, together with demographics, habitual diet and lifestyle characteristics, was obtained from direct interviews using a validated and reliable questionnaire. Unconditional logistic regression analyses were performed to examine the association between soy variables and type 2 diabetes risk.

RESULTS

Higher intake of total soyfoods was significantly associated with a lower risk of type 2 diabetes; the adjusted odds ratio (OR) for the highest versus the lowest intake was 0.31 (95% confidence interval (CI): 0.21-0.46; P<0.001). An inverse dose-response relationship of similar magnitude was also observed for total isoflavone intake (OR: 0.35; 95% CI: 0.24 to 0.49; P<0.001). In addition, inverse associations of specific soyfoods (soy milk, tofu and mung bean sprout) and major isoflavones (daidzein, genistein and glycitein) with the type 2 diabetes risk were evident.

CONCLUSIONS

Soyfood and isoflavone intake was associated with a lower type 2 diabetes risk in Vietnamese adults.

Decolorizing an anthraquinone dye by Phlebia brevispora: Intra-species characterization

Remazol brilliant blue R (RBBR) is an anthraquinone dye derived from anthracene that is decolorized by a white rot fungus, Phlebia brevispora. Interestingly, P. brevispora produces two phenomena of yellowish and pinkish colors during the degradation of RBBR. Here, we characterized the decolorization of RBBR by P. brevispora. The fungus was significantly different between the two colors via UV spectrophotometry, and the morphology of the hyphae observed in the respective color culture was also entirely different. Moreover, both of the two ligninolytic enzymes, laccase and manganese-dependent peroxidase (MnP), were remarkably stimulated in the yellowish culture at the beginning of the decolorization. It is possible that the RBBR decolorizing mechanism might be primarily related to the amount of laccase and MnP produced in the yellowish culture. Thus, the decolorized color may be rapidly estimated at initial period of incubation. In addition, GeneFishing technology revealed that two genes were differentially expressed in yellowish culture.

Heterologous expression of a new manganese-dependent peroxidase gene from Peniophora incarnata KUC8836 and its ability to remove anthracene in Saccharomyces cerevisiae

The white rot fungus Peniophora incarnata KUC8836 has received an attention as the greatest degrader of polycyclic aromatic hydrocarbons (PAHs), which are hazardous xenobiotics and recalcitrant pollutants. To characterize the mechanisms through which MnP degrades PAHs, heterologous expression of manganese-dependent peroxidase (MnP) gene pimp1 was performed in Saccharomyces cerevisiae BY4741 via the pGEM-T Easy vector, resulting in the recombinant plasmid pESC-URA/pimp1 containing the MnP signal peptide. MnP was significantly secreted into the culture medium with galactose as an active protein with higher efficiency (3.58 U mL^-1) by transformants than by the wild-type S. cerevisiae. The recombinant MnP protein was shown to have a molecular weight of 44 kDa by western blotting analysis. With regard to enhancing the bioremediation of PAHs in the environment, anthracene was effectively degraded by the MnP encoded by pimp1, with a degradation rate of 6.5% when Tween 80 was added. In addition, the MnP activity of the transformant exhibited the highest efficiency (2.49 U mL^-1) during the degradation. These results show that pimp1 might be useful for biodegradation and gene expression technologies at a transcriptional level, and genetic approaches can be improved by incorporating the highly ligninolytic gene pimp1 and the fungus P. incarnata KUC8836.

Plasma concentrations of coffee polyphenols and plasma biomarkers of diabetes risk in healthy Japanese women

Coffee consumption has been reported to reduce the risk of type 2 diabetes in experimental and epidemiological studies. This anti-diabetic effect of coffee may be attributed to its high content in polyphenols especially caffeic acid and chlorogenic acid. However, the association between plasma coffee polyphenols and diabetic risks has never been investigated in the literature. In this study, fasting plasma samples were collected from 57 generally healthy females aged 38-73 (mean 52, s.d. 8) years recruited in Himeji, Japan. The concentrations of plasma coffee polyphenols were determined by liquid chromatography coupled with mass tandem spectrometer. Diabetes biomarkers in the plasma/serum samples were analysed by a commercial diagnostic laboratory. Statistical associations were assessed using Spearman's correlation coefficients. The results showed that plasma chlorogenic acid exhibited negative associations with fasting blood glucose, glycated hemoglobin and C-reactive protein, whereas plasma total coffee polyphenol and plasma caffeic acid were weakly associated with these biomarkers. Our preliminary data support previous findings that coffee polyphenols have anti-diabetic effects but further replications with large samples of both genders are recommended.

RECENT TRENDS IN GENDER RATIO AT BIRTH IN HANGZHOU, CHINA

INTRODUCTION

Higher than normal sex ratios at birth in China have been reported since the early 1980's. This study aimed to investigate recent trends in sex ratio at birth in Hangzhou, capital of Zhejiang Province in southeast China.

METHODS

Information on selected maternal and birth-related characteristics was extracted from the Hangzhou Birth Information Database for all pregnant women who delivered live births during 2005-2014. The sex ratios at birth were calculated after excluding infants with missing data on gender and those born with ambiguous genitalia.

RESULTS

A total of 478,192 male births and 430,852 female births were recorded giving an overall ratio of 111.0. The sex ratio at birth was almost constant at around 110.7 during the period 2005-2008, followed by an increase to the peak at 113.1 in 2010 and then declined back to 109.6 in 2014.

CONCLUSION

The gender ratio at birth in Hangzhou remained unbalanced for the past decade.

Acute Neurological Illness in a Kidney Transplant Recipient Following Infection With Enterovirus-D68: An Emerging Infection?

We report the first case of enterovirus-D68 infection in an adult living-donor kidney transplant recipient who developed rapidly progressive bulbar weakness and acute flaccid limb paralysis following an upper respiratory infection. We present a 45-year-old gentleman who underwent pre-emptive living-donor kidney transplantation for IgA nephropathy. Eight weeks following transplantation, he developed an acute respiratory illness from enterovirus/rhinovirus that was detectable in nasopharyngeal (NP) swabs. Within 24 h of onset of respiratory symptoms, the patient developed binocular diplopia which rapidly progressed to multiple cranial nerve dysfunctions (acute bulbar syndrome) over the next 24 h. Within the next 48 h, asymmetric flaccid paralysis of the left arm and urinary retention developed. While his neurological symptoms were evolving, the Centers for Disease Control reported that the enterovirus strain from the NP swabs was, in fact, Enterovirus-D68 (EV-D68). Magnetic resonance imaging of the brain demonstrated unique gray matter and anterior horn cell changes in the midbrain and spinal cord, respectively. Constellation of these neurological symptoms and signs was suggestive for postinfectious encephalomyelitis (acute disseminated encephalomyelitis [ADEM]) from EV-D68. Treatment based on the principles of ADEM included intensive physical therapy and other supportive measures, which resulted in a steady albeit slow improvement in his left arm and bulbar weakness, while maintaining stable allograft function.

Fruit and vegetable consumption and risk of esophageal cancer: a case-control study in north-west China

The north-western region of China carries a big burden of esophageal cancer with incidence above the national average. This study ascertained the association between fruit and vegetable consumption and the risk of esophageal cancer in this remote part of China. A case-control study was undertaken in Urumqi and Shihezi, Xinjiang Uyghur Autonomous Region of China, between 2008 and 2009. Participants were 359 incident esophageal cancer patients and 380 hospital-based controls. Information on habitual fruit and vegetable consumption was obtained by face-to-face interview using a validated semiquantitative food frequency questionnaire. Unconditional logistic regression analyses were performed to assess the strength of the associations. The esophageal cancer patients consumed significantly less fruits (mean 364.3, standard deviation [SD] 497.4 g) and vegetables (mean 711.4, SD 727.9 g) daily than their counterparts without the disease (mean 496.5, SD 634.4 g and mean 894.5, SD 746.1 g, respectively). The adjusted odds ratios were 0.48 (95% confidence interval 0.33-0.71) and 0.46 (95% confidence interval 0.32-0.68) for consuming at least 515 g of fruits and 940 g of vegetables per day, respectively, relative to at most 170 g and 520 g. With respect to nutrients contained in fruits and vegetables, intakes of vitamin C, vitamin E, β-cryptoxanthin, potassium, and magnesium at high levels also reduced the esophageal cancer risk. In conclusion, inverse associations were evident between consumption of fruits and vegetables and the risk of esophageal cancer for adults residing in north-west China.

Sustainability of a physical activity and nutrition program for seniors

OBJECTIVE

This prospective cohort study aimed to determine the impact of a low cost, home-based physical activity and nutrition program for older adults at 6 months follow-up.

DESIGN

A follow-up survey was conducted 6 months after program completion via computer-assisted telephone interviewing. The International Physical Activity Questionnaire and the Fat and Fibre Barometer were used to measure physical activity levels and dietary behaviours, respectively. Self-reported height, weight, waist and hip circumferences were obtained. Changes over three time points of data collection (baseline, post-program, follow-up) and differences between the intervention and control groups were assessed. The use of program materials was also evaluated.

SETTING

Community and home-based.

PARTICIPANTS

Insufficiently active 60 to 70 year olds (n = 176, intervention and n = 198, control) residing in suburbs within the Perth metropolitan area.

RESULTS

A sustained improvement was observed for the intervention group in terms of fat avoidance behaviours (p interaction = .007). Significant improvements were found for strength exercises, fibre intake, body mass index and waist-to-hip ratio at either post-program or follow-up, however the overall effect was not significant. At post-program, the intervention group increased time spent participating in moderate activity by 50 minutes (p > .05), which was followed by a significant decline at follow-up (p < .05). Among intervention group participants, males and females differed with respect to strength exercises and moderate physical activity.

CONCLUSION

This low-cost physical activity and nutrition intervention resulted in a sustained improvement in fat avoidance behaviours and overall short-term gains in physical activity. Future studies for older adults are recommended to investigate gender-specific behavioural barriers as well as booster interventions which focus on physical activity.

Comparison between a moving bed bioreactor and a fixed bed bioreactor for biological phosphate removal and denitrification

Moving bed bioreactors (MBBR) and fixed bed bioreactors (FBBR) were compared for biological phosphorus removal and denitrification. The sorption denitrification P-elimination (S-DN-P) process was selected for this study. Results indicated that all nutrients were removed by the FBBR process compared with the MBBR process: 19.8% (total COD), 35.5% (filtered COD), 27.6% (BOD(5)), 62.2% (acetate), 78.5% (PO(4)-P), and 54.2% (NO(3)-N) in MBBR; 49.7% (total COD), 54.0% (filtered COD), 63.2% (BOD(5)), 99.6% (acetate), 98.6% (PO(4)-P), and 75.9% (NO(3)-N) in FBBR. The phosphate uptake and NO(3)-N decomposition in the FBBR process during the denitrification phase were much higher than for the MBBR process despite being of shorter duration. Results obtained from this study are helpful in elucidating the practical implications of using MBBR and FBBR for the removal of bio-P and denitrification from wastewater.

High incidence of respiratory infections in 'nil by mouth' tube-fed acute ischemic stroke patients

BACKGROUND

Respiratory infections are common in acute stroke. Previous studies have found dysphagia is associated with respiratory infections. Of interest is whether patients who are 'Nil by Mouth' (NBM) and tube fed have higher risk of developing infections due to aspiration of bacteria-laden saliva or refluxed material than stroke patients who are fed orally.

METHODS

Prospective cohort of 330 ischemic stroke survivors were followed for 30 days and infections recorded.

RESULTS

115 infections were treated with antibiotics; these included 51 respiratory infections. Incidence of infection in NBM tube-fed stroke patients (n = 74) was 69%, with 30 respiratory infections occurring in 74 patients who received enteral feeding after stroke. Logistic regression analysis showed tube feeding during admission was a significant risk for respiratory infection. We also saw a significant time-to-event effect with 73% (22/30) respiratory infections in tube-fed survivors diagnosed on days 2-4 after stroke, and 76% (39/51) of infections in all tube-fed survivors occurring by day 7 after stroke. Relevance to a theory of critical period of susceptibility to infection in acute stroke is discussed.

CONCLUSIONS

NBM tube-fed survivors were unlikely to have aspirated anything other than saliva/secretions or reflux, yet experienced significantly higher rates of respiratory infections than survivors fed orally. Stringent oral care and measures to prevent reflux are potentially modifiable aspects of stroke management.

Hospital admissions and length of stay for coronary disease in an Aboriginal cohort

BACKGROUND AND AIMS

Coronary disease (CHD)-related hospital admission is more common among indigenous than non-indigenous Australians. We aimed to identify predictors of hospital admission potentially useful in planning prevention programs.

METHODS AND RESULTS

Length of stay (LOS), interval between, and number of recurrent admissions were modelled with proportional hazards or negative binomial models using lifestyle data recorded in 1988-1989 among Aborigines (256 women, 258 men, aged 15-88years) linked to hospital records to 2002. Among 106 Aborigines with CHD, hypertension (hazard ratio (HR) 1.69, 95% CI 1.05-2.73); smoking (HR 1.90, 95% CI 1.02-3.53); consuming processed meat >4 times/month (HR 1.81, 95% CI 1.01-3.24); >6 eggs/week (HR 1.73, 95% CI 1.03-2.94); and lower intake of alcohol (HR 0.54, 95% CI 0.35-0.83) predicted LOS. Eating eggs (HR 1.05, 95% CI 1.01-1.09) and bush meats > or =7 times/month (HR 0.46, 95% CI 0.23-0.92) predicted interval between recurrent admissions. Hypertension (IRR 4.07; 95% CI 1.32-12.52), being an ex-drinker (IRR 6.60, 95% CI 2.30-19.00), eating red meat >6 times/week (IRR 0.98, 95% CI 0.97-0.99), bush meats >7 times/month (IRR 0.26, 95% CI 0.10-0.67), and adding salt to meals (IRR 3.16, 95% CI 1.12-8.92) predicted number of admissions.

CONCLUSION

Hypertension, alcohol drinking, smoking, and diet influence hospital admissions for CHD in Aboriginal Australians.

The CUPDAY Study: prebiotic-probiotic milk product in 1-3-year-old children attending childcare centres

AIM

The aim of the study was to evaluate the efficacy of a milk product containing probiotics and prebiotics (CUPDAY Milk) on the incidence of diarrhoea in children attending daycare centres.

METHODS

The study was undertaken in a randomized controlled trial with 496 children aged 1-3 years attending 29 childcare centres in Perth, Australia. The endpoint for the study was the number of days in which children were recorded as having four or more stools. The diarrhoeal rates were analyzed by Poisson regression using 'intention to treat' (all children) and 'reduced' (children enrolled for more than 10 days) data sets.

RESULTS

There was no difference in demographic characteristics between the case and control groups. In the 'intention to treat' analysis, a total of 41 745 child-days were included in the study. The adjusted risk ratio for those consuming the 'Cupday' milk drink was 0.82 (95% CI 0.73-0.94) for the intention to treat sample (n = 496) and 0.80 (95% CI 0.70-0.91) for the reduced sample (n = 315). The children consuming the 'Cupday' drink had a 20% reduction in the number of days experiencing four or more stools per day.

CONCLUSION

A milk containing probiotics and prebiotics reduced the number of days children attending child care who had four or more stools by 20%.

Health-related behaviours as predictors of mortality and morbidity in Australian Aborigines

OBJECTIVE

To examine predictors of coronary heart disease (CHD) and all-cause mortality in Aboriginal Australians.

METHOD

In 1988-89, a survey of Western Australian Aborigines (256 women, 258 men) aged 15-88 years documented diet, alcohol and smoking habits. Linkage to mortality and hospital admissions to the end of 2002 provided longitudinal data for modelling of coronary heart disease endpoints and all-cause mortality using Cox regression.

RESULTS

Coronary heart disease risk increased with smoking (HR 2.62, 95% CI: 1.19, 5.75), consumption of processed meats >once/week (HR 2.21, 95% CI: 1.05, 4.63), eggs >twice/week (HR 2.59, 95% CI: 1.11, 6.04) and using spreads on bread (HR 3.14. 95% CI: 1.03, 9.61). All-cause mortality risk was lower with exercise >once/week (HR 0.51, 95% CI 0.26, 1.05), increased in ex-drinkers (HR 3.66, 95% CI: 1.08, 12.47), heavy drinkers (HR 5.26, 95% CI: 1.46, 7.52) and with consumption of take away foods >nine times/month (HR 1.78, 95% CI 0.96, 3.29). Greater alcohol intake, smoking and adverse dietary choices clustered in 53% of men and 56% of women and increased risk of coronary heart disease (HR 2.1, 95% CI: 1.1, 4.0) and all-cause mortality (HR 2.3, 95% CI: 1.2, 4.2).

CONCLUSION

Lifestyle in Aboriginal Australians predicts coronary heart disease and all-cause mortality. Clustering of adverse behaviours is common and increases risk of coronary heart disease and death.

Alcohol intake and incidence of coronary disease in Australian aborigines

AIMS

To examine risk for coronary heart disease (CHD) and cardiovascular disease (CVD) in relation to alcohol in a cohort of Australian Aborigines.

METHODS

In 1988-1989, alcohol intake, drinking pattern, and beverage preference were elicited by interviewer-administered questionnaire in Western Australian Aborigines (258 men, 256 women) and cardiovascular outcomes ascertained through linkage to mortality and hospital admission records to 2002.

RESULTS

In proportional hazards models, risk for CHD, relative to lifetime abstainers, was significantly increased in ex-drinkers [Hazard ratio (HR) 2.29, 95% CL 1.23, 4.27], those drinking 41-60 g/day in men or 21-40 g/day in women (HR 2.80, 95% CL 1.04, 7.53), and those drinking >150 g/day for men or >100 g/day for women (HR 2.25, 95% CL 1.03, 4.90) with a J-shaped relationship. Low-to-moderate drinkers had lower waist girth, exercised more, and had a lower prevalence of overweight and smoking than at-risk drinkers. A preference for wine was associated with lower HR (0.28, 95% CL 0.10, 0.95). With CVD, only ex-drinkers showed significantly increased risk (HR 1.87, 95% CL 1.20, 2.91).

CONCLUSIONS

More favourable health-related behaviours in low-to-moderate drinkers suggest that lower risk could be mediated by lifestyle, as proposed in other populations.

Alcohol intake and incidence of coronary disease in Australian aborigines

AIMS

To examine risk for coronary heart disease (CHD) and cardiovascular disease (CVD) in relation to alcohol in a cohort of Australian Aborigines.

METHODS

In 1988-1989, alcohol intake, drinking pattern, and beverage preference were elicited by interviewer-administered questionnaire in Western Australian Aborigines (258 men and 256 women) and cardiovascular outcomes ascertained through linkage to mortality and hospital admission records to 2002.

RESULTS

In proportional hazards models, risk for CHD, relative to lifetime abstainers, was significantly increased in ex-drinkers [Hazard ratio (HR), 2.29; 95% confidence intervals (CI), 1.23-4.27], those drinking 41-60 g/day in men or 21-40 g/day in women (HR 2.80; 95% CI, 1.04-7.53) and those drinking >150 g/day for men or >100 g/day for women (HR, 2.25; 95% CI, 1.03-4.90) with a J-shaped relationship. Low-to-moderate drinkers had lower waist girth, exercised more and had a lower prevalence of overweight and smoking than at-risk drinkers. A preference for wine was associated with lower HR (0.28; 95% CI, 0.10-0.95). With CVD, only ex-drinkers showed significantly increased risk (HR, 1.87; 95% CI, 1.20-2.91).

CONCLUSIONS

More favourable health-related behaviours in low-to-moderate drinkers suggest that lower risk could be mediated by lifestyle, as proposed in other populations.

Emergency presentations by vulnerable road users: implications for injury prevention

Most emergency presentations by vulnerable road users were the result of collisions that did not involve a motor vehicle. Many injuries occurred off-road without police attendance. Hence, reliance on official police records would underestimate the magnitude and scope of these injuries. Suggestions to provide a safer road environment are given.

Morphological and immunophenotypic analysis of breast carcinomas with basal and myoepithelial differentiation

The aim of this study was to assess the morphological characteristics and immunohistochemical profile of breast carcinomas with basal and myoepithelial phenotypes to obtain a better understanding of their biological behaviour and nature. One thousand nine hundred and forty-four invasive breast carcinomas were examined, using tissue microarray (TMA) technology and immunohistochemistry, to identify those tumours that showed basal and myoepithelial phenotypes, and their immunophenotype profile was characterized using a variety of markers. In addition, haematoxylin and eosin-stained sections of these tumours were studied for several morphological parameters. The findings were correlated with patient and tumour characteristics and outcome data. Tumours were classified into two groups: (1) tumours with basal phenotype [expressing one or both basal markers (CK5/6 and/or CK14)] and (2) tumours with myoepithelial phenotype (expressing SMA and/or p63). Group 1 was further subdivided into two subgroups: (A) dominant basal pattern (more than 50% of cells positive) and (B) basal characteristics (10-50% of cells positive). Group 1 tumours constituted 18.6% (8.6% and 10% for groups 1A and 1B, respectively) and group 2 constituted 13.7% of the cases. In both groups, the most common histological types were ductal/no specific type, tubular mixed and medullary-like carcinomas; the majority of these tumours were grade 3. There were positive associations with adenoid cystic growth pattern, loss of tubule formation, marked cellular pleomorphism, poorer Nottingham prognostic index, and development of distant metastasis. In addition, associations were found with loss of expression of steroid hormone receptors and FHIT proteins and positive expression of p53 and EGFR. The most common characteristics in group 1 were larger size, high-grade comedo-type necrosis, development of tumour recurrence, and absence of lymph node disease. Group 2 tumours were more common in younger patients and were associated with central acellular zones, basaloid change, and positive E-cadherin protein expression. Group 1 characteristics were associated with both reduced overall survival (OS) [log rank (LR) = 22.5, p < 0.001] and reduced disease-free interval (DFI) (LR = 30.1, p < 0.001), while group 2 characteristics showed an association with OS (LR = 5, p = 0.02) but not with DFI. Multivariate analysis showed that basal, but not myoepithelial, phenotype has an independent value in predicting outcome. Breast cancers with basal and myoepithelial phenotypes are distinct groups of tumours that share some common morphological features and an association with poor prognosis. The basal rather than the myoepithelial phenotype has the strongest relationship with patient outcome.

Indoor environmental quality in a 'low allergen' school and three standard primary schools in Western Australia

To investigate indoor environmental quality in classrooms, assessments were undertaken in a 'low allergen' school and three standard primary schools in Western Australia. Dust allergens, air pollutants and physical parameters were monitored in the four schools at four times (summer school term, autumn holiday, winter school term and winter holiday) in 2002. The levels of particulate matter (PM(10)) and volatile organic compounds were similar between the four primary schools. Although slightly decreased levels of dust-mite and cat allergens were observed in the 'low allergen' school, the reductions were not statistically significant and the allergen levels in all schools were much lower than the recommended sensitizing thresholds. However, significantly lower levels of relative humidity and formaldehyde level during summer-term were recorded in the 'low allergen' school. In conclusion, the evidence here suggests that the 'low allergen' school did not significantly improve the indoor environmental quality in classrooms. Practical Implications School is an important environment for children in terms of exposure to pollutants and allergens. By assessing the levels of key pollutants and allergens in a low allergen school and three standard primary schools in Western Australia, this study provides useful information for implementation of healthy building design that can improve the indoor environment in schools.

Contraception within six-month postpartum in rural Vietnam: implications on family planning and maternity services

OBJECTIVES

This longitudinal study documents contraception practice and factors influencing contraception decision within the first six months postpartum, amongst women residing in the rural Northern Central region of Vietnam.

METHODS

A sample of 463 rural women who gave birth during August-October 2002 were recruited and interviewed at one, 16 and 24 weeks postpartum.

RESULTS

The proportion of contraceptive users at weeks 16 and 24 were 17% and 43% respectively. At week 24, of contraceptive users, 57% used IUD, 25% used condom, and 14% used traditional methods. Logistic regression analysis found age, sufficient knowledge on contraceptives and husband/partner opinion can significantly affect the contraception decision.

CONCLUSIONS

In order to improve the situation, health authorities should be encouraged to provide counselling on postpartum contraceptive methods during ante- and postnatal care visits. Health education on family planning and breastfeeding should also involve the husband/partner group taking into account local socio-cultural features.

A quantitative food frequency questionnaire for women in southeast China: development and reproducibility

This study describes the development and reproducibility of a 128-item quantitative food frequency questionnaire (FFQ) to measure usual food consumption for women in southeast China. The FFQ was pre-tested using 51 Chinese women who recently migrated to Australia. Cronbach's alpha coefficient was 0.81 for internal consistency. The reliability of the FFQ was then assessed by another test-retest study. A sample of 41 women residing in southeast China was interviewed twice within 12 weeks. Intraclass correlation coefficients were moderate to high for mean food group consumption (0.43-0.96) and mean daily nutrient intakes (0.47-0.89). Kappa statistics for eating habits ranged from 0.27 to 0.89 in the test-retest. The mean ratio of energy intake to basal metabolic rate was 1.73 (S.D. 0.39) in both test and retest samples. The study confirmed that the FFQ method using standard containers is appropriate to assess dietary intake for women in southeast China.

Prolonged lactation reduces ovarian cancer risk in Chinese women

To investigate the effect of lactation on the risk of ovarian cancer for Chinese women, a case-control study was conducted in Hangzhou, capital of Zhejiang province, China. Cases were 275 patients with histologically confirmed epithelial ovarian cancer. Controls were 623 women without neoplasm. All participants were parous women who had given at least one live birth and had been residents of Zhejiang province for at least 10 years. Information was collected using a validated and reliable questionnaire on total months of lactation, number of children breastfed, and average duration of lactation per child. Multivariate logistic regression models were used to assess the association between ovarian cancer risk and lactation variables, accounting for age, locality, full-term pregnancy, oral contraceptive use and family history of the cancer. The adjusted odds ratios were 0.51 (95% confidence interval (CI) 0.3-0.9) and 0.44 (95% CI 0.2-0.9) respectively for women with over 12 months of lactation and at least three children breastfed, compared with those with 4 months or less lactation and one child breastfed. The corresponding dose-response relationships were also significant (P<0.05). Therefore, prolonged lactation could reduce the risk of ovarian cancer for Chinese women.

Altered glycosylation leads to Tr polyagglutination

BACKGROUND

Polyagglutination refers to red blood cells (RBCs) that are agglutinated by a high proportion of ABO-matched adult sera but not by cord sera. Polyagglutinable RBCs have been associated with microbial infection, myeloproliferative disorders, and myelodysplasia. Lectins aid in the identification of polyagglutination.

CASE STUDY

A Hispanic male infant with mild hemolytic anemia, a "Bernard-Soulier-like" syndrome, intermittent neutropenia, mitral valve regurgitation, ligament hyperlaxity, and mild mental retardation was studied. The patient's Group O RBCs were polyagglutinable; they were agglutinated by normal human sera, several lectins [including Arachis hypogea, Salvia sclarea, Salvia horminum, Glycine max, Ulex europaeus, Griffonia simplicifolia I, and Gr. simplicifolia II], and some monoclonal antibodies. His RBCs were not agglutinated by cord sera, Dolichos biflorus, or Phaseolus lunatus. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis on the RBC membranes followed by staining with periodic acid-Schiff stain showed markedly reduced staining of glycophorins A and B. Staining with Coomassie brilliant blue revealed that Band 3 has a faster mobility than normal.

CONCLUSIONS

Collectively, the results suggest that the patient's RBCs have a reduction in N-acetylneuraminic acid on both N- and O-glycans, exposing, respectively, beta1,4-galactosidase and beta1,3-galactosidase. The patient likely has an altered glycosyltransferase that results in defective glycosylation in RBCs and other cell lineages. This type of polyagglutination was named Tr.

Hospitalisation for gastroenteritis in Western Australia

AIMS

To document gastroenteritis hospitalisations of the 1995-96 cohort of infants born in Western Australia to mid-2002, and to assess factors associated with their hospitalisations and readmissions.

METHODS

Retrospective analysis of the State's hospitalisation data, Midwives' Notification of Births data, the Australian Bureau of Statistics mortality data and clinical and demographic information.

RESULTS

Aboriginal infants were hospitalised for gastroenteritis eight times more frequently than their non-Aboriginal peers, and were readmitted more frequently and sooner for diarrhoeal illnesses than the other group. They also stayed in hospital for twice as long and many Aboriginal patients were hospitalised on numerous occasions. Hospitalisation rates were higher in remote areas and were significantly associated with co-morbidities such as undernutrition, anaemia, co-existing infections, and intestinal carbohydrate intolerance.

CONCLUSIONS

Gastroenteritis is very prevalent in Australian Aboriginal infants and children and is a major cause of their hospitalisation in Western Australia. It is often associated with undernutrition, anaemia, intestinal parasitic infestations, other infections, intestinal carbohydrate intolerance, and, in some instances, with low birth weight. This is often due to unhygienic living conditions and behaviours and presents major challenges to public health, health promotion, and clinical personnel, particularly paediatric services. Childhood diarrhoeal diseases occur commonly in other indigenous groups but have not received the attention that they deserve.

Do preserved foods increase prostate cancer risk?

Preserved foods have been found in some studies to be associated with increased cancer risks. The possible relationship between preserved foods and prostate cancer was investigated in a case-control study in southeast China during 2001-2002 covering 130 histologically confirmed cases and 274 inpatient controls without malignant disease. The total amount of preserved food consumed was positively associated with cancer risk, the adjusted odds ratio being 7.05 (95% CI: 3.12-15.90) for the highest relative to the lowest quartile of intake. In particular, the consumption of pickled vegetables, fermented soy products, salted fish and preserved meats was associated with a significant increase in prostate cancer risk, all with a significant dose-response relationship.

Factors influencing hospitalisation of infants for recurrent gastroenteritis in Western Australia

OBJECTIVE

To determine factors affecting length of hospitalisation of infants for recurrent gastroenteritis using linked data records from the Western Australia heath information system.

METHODS

A seven-year retrospective cohort study was undertaken on all infants born in Western Australia in 1995 who were admitted for gastroenteritis during their first year of life (n = 519). Linked hospitalisation records were retrieved to derive the outcome measure and other demographic variables for the cohort. Unlike previous studies that focused mainly on a single episode of gastroenteritis, the durations of successive hospitalisations were analysed using a proportional hazards model with correlated frailty to determine the prognostic factors influencing recurrent gastroenteritis.

RESULTS

Older children experienced a shorter stay with an increased discharge rate of 1.9% for each month increase in admission age. An additional co-morbidity recorded in the hospital discharge summary slowed the adjusted discharge rate by 46.5%. Aboriginal infants were readmitted to hospital more frequently, and had an adjusted hazard ratio of 0.253, implying a much higher risk of prolonged hospitalisation compared to non-Aborigines.

CONCLUSIONS

The use of linked hospitalisation records has the advantage of providing access to hospital-based population information in the context of medical informatics. The analysis of linked data has enabled the assessment of prognostic factors influencing length of hospitalisations for recurrent gastroenteritis with high statistical power.

Factors affecting length of hospitalization of infants and children for recurrent gastroenteritis in Western Australia

AIM

Aboriginal infants in Western Australia (WA) have much higher rates of hospitalization for gastroenteritis than do their non-Aboriginal peers. The aim of this 7-y retrospective study was to investigate the factors affecting the duration of hospitalizations due to recurrent gastroenteritis in WA.

METHODS

All infants born in WA in 1995 and 1996 who had indexed gastroenteritis admissions during their first year of life (n = 1009) were followed until 31 May 2002. Linked hospitalization and birth records were retrieved to derive the outcome measures, associated co-morbidities and other demographic variables. A proportional hazards frailty model was then used to determine factors influencing discharge from hospital for the study cohort.

RESULTS

Aboriginal patients were readmitted to hospital more frequently and stayed in hospital more than twice as long as non-Aborigines. Factors that slowed the rate of discharge from hospital included Indigenous status and the presence of coexisting conditions such as dehydration, sugar intolerance, failure to thrive and iron-deficiency anaemia.

CONCLUSION

Gastrointestinal infections are common illnesses in infants and children, particularly for those who live in overcrowded and unhygienic conditions. Coexisting morbidities including undernutrition, nutrient deficiencies, other infections and gastrointestinal carbohydrate intolerance contribute to prolonged and recurrent hospitalization. Multifaceted clinical, disease prevention and health/hygiene promotion are needed to lessen the burden of these infections.

Perceptions of the quality of life for the adolescent with a chronic illness by teachers, parents and health professionals: a Delphi study

AIMS

The perceptions that teachers, parents and health professionals have on the relative importance of different aspects of quality of life (QOL) for the adolescent with a chronic illness were explored using a three-round Delphi study.

METHODS

The first round questionnaire identified the level of importance each panel attached to 16 aspects relating to QOL. Panellists were also encouraged to provide additional comments on why they felt a particular item was important. In round two, panellists were asked to prioritize the items in order of importance, whereas round three attempted to achieve consensus among each of the three panels.

RESULTS

Differences between and within panels in the prioritization of items in round one and round two were evident. However, consensus was achieved in round three, except for the prioritization of very important items by the panel of teachers. Items identified by all three panels as extremely important included the adolescent's attitude, family relationships and friendships with the same age group. Themes to emerge from the qualitative responses to the open-ended questions included the perception of the chronically ill adolescent 'not wanting to be different' and the importance of a 'positive attitude'. The majority of participants also perceived adolescents with a chronic illness as having worse QOL than their healthy counterparts.

CONCLUSIONS

By increasing the awareness among the different groups of the impact of chronic illness on various aspects of adolescent QOL, the overall care and support of those adolescents could be improved. Further studies should also be undertaken to explore the views of the chronically ill adolescents themselves.

Assessing quality of life for adolescents in western Australia

This study investigates the quality of life (QOL) for adolescents residing in Perth, Western Australia. The Quality of Life Profile-Adolescent Version (QOLPAV), a generic self-reported questionnaire, was administered to 363 adolescents aged between ten and 18 years who were enrolled in 20 high schools within metropolitan Perth. Stepwise regression analysis of the data showed that age, control, opportunity and perceptions of health have significant associations with QOL. It was also found that adolescents with a chronic condition and those without have similar QOL scores. This suggests that, in terms of QOL, the chronically ill adolescents do not view themselves as different from their healthy counterparts.

Diet and ovarian cancer risk: a case-control study in China

This case-control study, conducted in Zhejiang, China during 1999-2000, investigated whether dietary factors have an aetiological association with ovarian cancer. Cases were 254 patients with histologically confirmed epithelial ovary cancer. The 652 controls comprised 340 hospital visitors, 261 non-neoplasm hospital outpatients without long-term diet modifications and 51 women recruited from the community. A validated food frequency questionnaire was used to measure the habitual diet of cases and controls. The risks of ovarian cancer for the dietary factors were assessed by adjusted odds ratios based on multivariate logistic regression analysis, accounting for potential confounding demographic, lifestyle, familial factors and hormonal status, family ovarian cancer history and total energy intake. The ovarian cancer risk declined with increasing consumption of vegetables and fruits but vice versa with high intakes of animal fat and salted vegetables. The adjusted upper quartile odds ratio compared to the lower quartile was 0.24 (0.1-0.5) for vegetables, 0.36 (0.2-0.7) for fruits, 4.6 (2.2-9.3) for animal fat and 3.4 (2.0-5.8) for preserved (salted) vegetables with significant dose-response relationship. The risk of ovarian cancer also appeared to increase for those women preferring fat, fried, cured and smoked food.

Public versus private hospital maternity length of stay: a gamma mixture modelling approach

Application of a gamma mixture model to obstetrical diagnosis-related groups (DRGs) revealed heterogeneity of maternity length of stay (LOS). The proportion of long-stay subgroups identified, which can account for 30% of admissions, varied between DRGs. The burden of long-stay patients borne was estimated to be much higher in private hospitals than public hospitals for normal delivery, but vice versa for Caesarean section. Such differences highlights the impact of DRG-based casemix funding on inpatient LOS and have significant implications for health insurance companies to integrate casemix funding across the public and private sectors. The analysis also benefits hospital administrators and managers to budget expenditures accordingly.

Determinants of maternity length of stay: a Gamma mixture risk-adjusted model

With obstetrical delivery being the most frequent cause for hospital admissions, it is important to determine health- and patient-related characteristics affecting maternity length of stay (LOS). Although the average inpatient LOS has decreased steadily over the years, the issue of the appropriate LOS after delivery is complex and hotly debated, especially since the introduction of the mandatory minimum-stay legislation in the USA. The purpose of this paper is to identity factors associated with maternity LOS and to model variations in LOS. A Gamma mixture risk-adjusted model is proposed in order to analyze heterogeneity of maternity LOS within obstetrical Diagnosis Related Groups (DRGs). The determination of pertinent factors would benefit hospital administrators and clinicians to manage LOS and expenditures efficiently.

Zero-inflated Poisson regression with random effects to evaluate an occupational injury prevention programme

This study presents a zero-inflated Poisson regression model with random effects to evaluate a manual handling injury prevention strategy trialled within the cleaning services department of a 600 bed public hospital between 1992 and 1995. The hospital had been experiencing high annual rates of compensable injuries of which over 60 per cent were attributed to manual handling. The strategy employed Workplace Risk Assessment Teams (WRATS) that utilized a workplace risk identification, assessment and control approach to manual handling injury hazard reduction. The WRATS programme was an intervention trial, covering the 1988-1995 financial years. In the course of compiling injury counts, it was found that the data exhibited an excess of zeros, in the context that the majority of cleaners did not suffer any injuries. This phenomenon is typical of data encountered in the occupational health discipline. We propose a zero-inflated random effects Poisson regression model to analyse such longitudinal count data with extra zeros. The WRATS intervention and other concomitant information on individual cleaners are considered as fixed effects in the model. The results provide statistical evidence showing the value of the WRATS programme. In addition, the methods can be applied to assess the effectiveness of intervention trials on populations at high risk of manual handling injury or indeed of injury from other hazards.

Determining the effects of patient casemix on length of hospital stay: a proportional hazards frailty model approach

OBJECTIVES

To identify factors associated with hospital length of stay (LOS) and to model variations in LOS within Diagnosis Related Groups (DRGs).

METHODS

A proportional hazards frailty modelling approach is proposed that accounts for patient transfers and the inherent correlation of patients clustered within hospitals. The investigation is based on patient discharge data extracted for a group of obstetrical DRGs.

RESULTS

Application of the frailty approach has highlighted several significant factors after adjustment for patient casemix and random hospital effects. In particular, patients admitted for childbirth with private medical insurance coverage have higher risk of prolonged hospitalization compared to public patients.

CONCLUSIONS

The determination of pertinent factors provides important information to hospital management and clinicians in assessing the risk of prolonged hospitalization. The analysis also enables the comparison of inter-hospital variations across adjacent DRGs.

Measuring resident satisfaction in residential aged care

PURPOSE

The aims of this study were to assess the factor structure, reliability, and validity of an existing Resident Satisfaction Questionnaire (RSQ) and to develop a short-form RSQ for regular use in residential aged care settings.

DESIGN AND METHODS

A cross-sectional survey design was adopted to collect the required information, with facilities being selected using stratified random sampling. Both exploratory and confirmatory factor analyses were conducted on a sample of 1,146 residents in 70 residential aged care facilities in Western Australia.

RESULTS

The RSQ is confirmed to be a reliable, valid, context-relevant, and easy-to-use instrument for assessing residents' satisfaction with their residential aged care facilities. Resident satisfaction, as assessed via the RSQ, was found to be a multidimensional construct comprising six factors-Room, Home, Social Interaction, Meals Service, Staff Care, and Involvement.

IMPLICATIONS

A 24-item short version of the RSQ can be constructed based on the six-factor resident satisfaction measurement model and used as a regular monitoring tool of resident satisfaction for quality improvement purposes.

DNA analysis for the Dombrock polymorphism

BACKGROUND

RBC typing for Do(a) and Do(b) is notoriously difficult, and inaccurate typing can predispose patients to hemolytic transfusion reactions. The DO1/DO2 polymorphism is associated with three nucleotide changes: 378 C>T, 624 T>C and 793 A>G. While the 378 C>T- and 624 T>C-containing codons are silent mutations, the 793 A>G polymorphism in codon 265 encodes asparagine for Do(a) and aspartic acid for Do(b).

STUDY DESIGN AND METHODS

Described here are two PCR-RFLP assays, one using the Mnl I site associated with 624C (DO2) and the other altering two nucleotides within the sense primer, which allows recognition of 793G by the Eam 1105 I.

RESULTS

The assays have been performed on over 100 samples for which the RBC typing of one or both antigens was known. Eight samples had been historically mistyped by hemagglutination.

CONCLUSION

This RFLP assay provides a practical method for typing donor blood for Dombrock alleles.