Vaccine safety surveillance in Kenya using GAIA standards: A feasibility assessment of existing national and subnational research and program systems.

BACKGROUND: Active surveillance systems for monitoring vaccine safety among pregnant women address some of the limitations of a current passive surveillance approach utilized in low- and middle-income countries (LMIC). However, few active surveillance systems in LMIC exist. Our study assessed the feasibility of utilizing three existing data collection systems in Kenya for active surveillance of maternal immunization and to assess the applicability of Global Alignment of Immunization Safety Assessment in pregnancy (GAIA) case definitions that were initially developed for clinical trials within these systems. METHODS: We assessed applicability of GAIA case definition for maternal Tetanus Toxoid exposure, stillbirth, low birth weight, small for gestational age, Neonatal Invasive Blood Stream Infection (NIBSI), prematurity and neonatal death in two routine web-based health information systems (Kenya EMR and DHIS-2), and a web-based population-based pregnancy research platform (ANCOV1) in Kenya. RESULTS: All three HIS were capable of reporting selected outcomes to varying degrees of GAIA certainty. The ANCOV platform was the most robust in collecting and collating clinical data for effective maternal pharmacovigilance. The utilization of facility- and district-aggregated data limits the usefulness of DHIS-2 in pharmacovigilance as currently operationalized. While the Kenya EMR contained individual level data and meets the key considerations for effective pharmacovigilance, it was used primarily for HIV care and treatment records in a small proportion of health facilities and would require additional resources to expand to all antenatal care facilities and to link maternal and infant records. DISCUSSION: Population-based research studies may offer a responsive short-term option for implementing maternal vaccine pharmacovigilance in LMICs. However, the foundation exists for long-term capacity building within the national health electronic data systems to provide this critical service as well as ensure participation of the country in international studies on maternal vaccine safety.

Initial experience of TAS-102 chemotherapy in Australian patients with Chemo-refractory metastatic colorectal cancer.

For patients with refractory metastatic colorectal cancer (mCRC) treatment with Trifluridine/Tipiracil, also known as TAS-102, improves overall survival. This study aims to investigate the efficacy and safety of TAS-102 in a real-world population from Victoria, Australia. A retrospective analysis of prospectively collected data from the Treatment of Recurrent and Advanced Colorectal Cancer (TRACC) registry was undertaken. The characteristics and outcomes of patients receiving TAS-102 were assessed and compared to those enrolled in the registration study (RECOURSE). Across 13 sites, 107 patients were treated with TAS-102. The median age was 60 years (range: 31-83), compared to 63 for RECOURSE. Comparing registry TAS-102-treated and RECOURSE patients, 75% vs 100% were ECOG performance status 0-1, 74% vs 79% had initiated treatment more than 18 months from diagnosis of metastatic disease and 36% vs 49% were RAS wild-type. Median time on treatment was 10.4 weeks (range: 1.7-32). Median progression-free survival (PFS) was 3.3 months compared to 2 months in RECOURSE, while median overall survival was the same at 7.1 months. Two patients (2.3%) had febrile neutropenia and there were no treatment-related deaths, where TAS-102 dose at treatment initiation was at clinician discretion.TRACC registry patients treated with TAS-102 were younger than those from the RECOURSE trial, with similar overall survival observed. Less strict application of RECIST criteria and less frequent imaging may have contributed to an apparently longer PFS.

Cognitive Stimulation for Persons with Dementia: a Systematic Review and Meta-Analysis.

OBJECTIVE: We aim to provide an up-to-date systematic review and meta-analysis of the effects of cognitive stimulation (CS) on cognition, depressive symptoms, and quality of life in persons with dementia. Factors affecting the treatment effect were examined. METHODS: A literature search was performed on databases of MEDLINE, EMBASE, PsycINFO, CINAHL Plus, and Cochrane Library up to 7 March 2019. Only randomised controlled trials investigating the effects of CS in persons with dementia were included. The outcome measures were cognitive function, depressive symptoms, and quality of life. RESULTS: 20 randomised controlled trials with a total of 1251 participants (intervention group: 674; control group: 577) were included for meta-analysis. Most participants had mild to moderate dementia. CS had a significant positive small-to-moderate effect on cognition (Hedges's g = 0.313, p < 0.001). Heterogeneity of CS was low to moderate (Q=30.5854, df=19, p < 0.05, I2 = 37.877%). Inconclusive results were found for depressive symptoms and quality of life. CONCLUSION: CS has a significant positive effect on cognitive function, but its effect on depressive symptoms and quality of life was inconclusive. Future studies with more robust methodology establishing evidence of its efficacy are required.

Mindfulness-Based Cognitive Therapy for Late-Life Depression: a Randomised Controlled Trial.

BACKGROUND: Rumination and overgeneral autobiographical memory are dysfunctional cognitions commonly found in older adults with depression. The theoretical underpinnings of mindfulness-based cognitive therapy (MBCT) address the ruminative tendencies and the non-specific retrieval of autobiographical memories. This study aims to examine the efficacy and cognitive mechanisms of MBCT in older adults with active depressive symptoms. METHODS: 57 older adults (mean age, 70 years) with normal cognition and mild to moderate depressive symptoms were randomly allocated to either the MBCT group or the active control group for 8 weeks. The MBCT group consisted of eight 2-hour weekly sessions and a 7-hour full-day retreat, with different themes for each class, guided mindfulness exercises, feedback and discussion, homework review, and psychoeducation. The active control group comprised a 1-hour physical exercise and a standardised health education of the specific theme with group discussion (eg fall prevention, chronic pain). Participants were assessed before and after the 8-week intervention for four outcome measures: the Hamilton Depression Rating Scale (HAMD), the Ruminative Response Scale (RRS), the Autobiographical Memory Test (AMT), and the Mindful Attention Awareness Scale (MAAS). RESULTS: There was a significant reduction in severity of depressive symptoms (HAMD score) in both the MBCT group (F(1, 27) = 35.9, p < 0.001, η2 = 0.57) and the active control group (F(1, 28) = 9.29, p < 0.01, η2 = 0.24), but only the MBCT group showed substantial improvements in autobiographical memory specificity (AMT score), rumination (RRS score), and mindfulness (MAAS score). CONCLUSION: Although both MBCT and active control programme decrease the severity of depressive symptoms in older adults, only MBCT improves AMS, rumination, and mindfulness. Our findings provide empirical support for the theoretical underpinnings of MBCT. Older adults with more severe depression and more severe dysfunctional cognition may benefit more from the specific therapeutic effects of MBCT.

Prognostic value of MACC1 and proficient mismatch repair status for recurrence risk prediction in stage II colon cancer patients: the BIOGRID studies.

BACKGROUND: We assessed the novel MACC1 gene to further stratify stage II colon cancer patients with proficient mismatch repair (pMMR). PATIENTS AND METHODS: Four cohorts with 596 patients were analyzed: Charité 1 discovery cohort was assayed for MACC1 mRNA expression and MMR in cryo-preserved tumors. Charité 2 comparison cohort was used to translate MACC1 qRT-PCR analyses to FFPE samples. In the BIOGRID 1 training cohort MACC1 mRNA levels were related to MACC1 protein levels from immunohistochemistry in FFPE sections; also analyzed for MMR. Chemotherapy-naïve pMMR patients were stratified by MACC1 mRNA and protein expression to establish risk groups based on recurrence-free survival (RFS). Risk stratification from BIOGRID 1 was confirmed in the BIOGRID 2 validation cohort. Pooled BIOGRID datasets produced a best effect-size estimate. RESULTS: In BIOGRID 1, using qRT-PCR and immunohistochemistry for MACC1 detection, pMMR/MACC1-low patients had a lower recurrence probability versus pMMR/MACC1-high patients (5-year RFS of 92% and 67% versus 100% and 68%, respectively). In BIOGRID 2, longer RFS was confirmed for pMMR/MACC1-low versus pMMR/MACC1-high patients (5-year RFS of 100% versus 90%, respectively). In the pooled dataset, 6.5% of patients were pMMR/MACC1-low with no disease recurrence, resulting in a 17% higher 5-year RFS [95% confidence interval (CI) (12.6%-21.3%)] versus pMMR/MACC1-high patients (P = 0.037). Outcomes were similar for pMMR/MACC1-low and deficient MMR (dMMR) patients (5-year RFS of 100% and 96%, respectively). CONCLUSIONS: MACC1 expression stratifies colon cancer patients with unfavorable pMMR status. Stage II colon cancer patients with pMMR/MACC1-low tumors have a similar favorable prognosis to those with dMMR with potential implications for the role of adjuvant therapy.

A solid state highly emissive Cu(i) metallacycle: promotion of cuprophilic interactions at the excited states.

The straightforward synthesis of a new Cu(i) metal-rich small metallacycle is presented. This compound is luminescent in the solid state with an emission quantum yield of 72% at room temperature and displays a pronounced reversible red-shift of its emission spectra upon cooling. Quantum chemical calculations reveal that these properties are governed by important geometrical relaxations that imply the formation of cuprophilic interactions at the excited states.

Circulating tumor DNA as an early marker of therapeutic response in patients with metastatic colorectal cancer.

BACKGROUND: Early indicators of treatment response in metastatic colorectal cancer (mCRC) could conceivably be used to optimize treatment. We explored early changes in circulating tumor DNA (ctDNA) levels as a marker of therapeutic efficacy. PATIENTS AND METHODS: This prospective study involved 53 mCRC patients receiving standard first-line chemotherapy. Both ctDNA and CEA were assessed in plasma collected before treatment, 3 days after treatment and before cycle 2. Computed tomography (CT) scans were carried out at baseline and 8-10 weeks and were centrally assessed using RECIST v1.1 criteria. Tumors were sequenced using a panel of 15 genes frequently mutated in mCRC to identify candidate mutations for ctDNA analysis. For each patient, one tumor mutation was selected to assess the presence and the level of ctDNA in plasma samples using a digital genomic assay termed Safe-SeqS. RESULTS: Candidate mutations for ctDNA analysis were identified in 52 (98.1%) of the tumors. These patient-specific candidate tissue mutations were detectable in the cell-free DNA from the plasma of 48 of these 52 patients (concordance 92.3%). Significant reductions in ctDNA (median 5.7-fold; P < 0.001) levels were observed before cycle 2, which correlated with CT responses at 8-10 weeks (odds ratio = 5.25 with a 10-fold ctDNA reduction; P = 0.016). Major reductions (≥10-fold) versus lesser reductions in ctDNA precycle 2 were associated with a trend for increased progression-free survival (median 14.7 versus 8.1 months; HR = 1.87; P = 0.266). CONCLUSIONS: ctDNA is detectable in a high proportion of treatment naïve mCRC patients. Early changes in ctDNA during first-line chemotherapy predict the later radiologic response.

Treatment and outcomes of metastatic colorectal cancer in Australia: defining differences between public and private practice.

BACKGROUND: Prior studies have suggested improved outcomes for cancer patients managed in private centres, despite universal healthcare within Australia. AIMS: To compare patient, disease, treatment and survival data for metastatic colorectal cancer (mCRC) managed in private versus public centres. METHODS: Analysis of prospectively collected registry data for consecutive patients with mCRC managed at 16 participating centres from July 2009. RESULTS: Data for 1065 patients were examined. Age, gender and Charlson comorbidity score were similar for public and private patients. Private patients were more commonly Eastern Cooperative Oncology Group performance score 0-1 (85% vs 78%, P = 0.008), in the highest Index of Relative Socioeconomic Advantage and Disadvantage quintile (57% vs 18%, P < 0.001) or had a single metastatic site (62% vs 54%, P = 0.009). Patients treated in private were more likely to receive chemotherapy (84% vs 70%, P < 0.001), bevacizumab (59% vs 50%, P = 0.008), be treated with curative intent (37% vs 26%, P < 0.001) and undergo metastasectomy (30% vs 22%, P = 0.001). These management differences remained statistically significant after adjusting for baseline characteristics. Management in the private setting was associated with superior overall survival (median 27.9 vs 20 months, hazard ratio 0.7, 95% confidence interval: 0.57 to 0.86, P = 0.001), significant in multivariate analysis adjusting for all baseline covariates. CONCLUSIONS: Significant differences in baseline characteristics were noted for private versus public patients. However, these do not explain the higher rates of treatment delivery in the private setting, which likely contributed towards the observed survival difference. Further studies are required to determine if the increased likelihood of intervention in the private setting is driven by patient, clinician and/or institutional factors.

Multicenter retrospective analysis of metastatic colorectal cancer (CRC) with high-level microsatellite instability (MSI-H).

BACKGROUND: The microsatellite instability-high (MSI-H) phenotype, present in 15% of early colorectal cancer (CRC), confers good prognosis. MSI-H metastatic CRC is rare and its impact on outcomes is unknown. We describe survival outcomes and the impact of chemotherapy, metastatectomy, and BRAF V600E mutation status in the largest reported cohort of MSI-H metastatic colorectal cancer (CRC). PATIENTS AND METHODS: A retrospective review of 55 MSI-H metastatic CRC patients from two institutions, Royal Melbourne Hospital (Australia) and The University of Texas MD Anderson Cancer Center (United States), was conducted. Statistical analyses utilized Kaplan-Meier method, Log-rank test, and Cox proportional hazards models. RESULTS: Median age was 67 years (20-90), 58% had poor differentiation, and 45% had stage IV disease at presentation. Median overall survival (OS) from metastatic disease was 15.4 months. Thirteen patients underwent R0/R1 metastatectomies, with median OS from metastatectomy 33.8 months. Thirty-one patients received first-line systemic chemotherapy for metastatic disease with median OS from the start of chemotherapy 11.5 months. No statistically significant difference in progression-free survival or OS was seen between fluoropyrimidine, oxaliplatin, or irinotecan based chemotherapy. BRAF V600E mutation was present in 14 of 47 patients (30%). BRAF V600E patients demonstrated significantly worse median OS; 10.1 versus 17.3 months, P = 0.03. In multivariate analyses, BRAF V600E mutants had worse OS (HR 4.04; P = 0.005), while patients undergoing metastatectomy (HR 0.11; P = <0.001) and patients who initially presented as stage IV disease had improved OS (HR 0.27; P = 0.003). CONCLUSIONS: Patients with MSI-H metastatic CRC do not appear to have improved outcomes. BRAF V600E mutation is a poor prognostic factor in MSI-H metastatic CRC.

Developing a national database for metastatic colorectal cancer management: perspectives and challenges.

BACKGROUND: The changing treatment landscape for metastatic colorectal cancer creates multiple potential treatment strategies. An Australian-centric database capturing comprehensive information across a range of treatment locations would create a valuable resource enabling multiple important research questions to be addressed. AIMS: To establish a collection of a consensus dataset capturing treatment and outcomes at multiple public and private hospitals across Australia. METHODS: An electronic database was developed by a panel of clinicians, to capture an agreed dataset for patients with newly diagnosed metastatic colorectal cancer. Of particular interest were clinician decision-making, the impact of comorbidities and the frequency of major adverse events. RESULTS: Since July 2009, data collection has been established at six public and eight private hospitals across three Australian states and territories. Successful linkage and analysis, with support from BioGrid Australia, of selected data on the initial 864 patients demonstrates that data can be captured from diverse sites, including public and private practice, that multiple factors impact on treatment delivered and outcomes achieved and that comprehensive data on rare but important adverse events can be captured. As a clinical research tool, the project has been highly successful, generating multiple presentations at national and international conferences related to a diverse range of research questions. CONCLUSIONS: Multistate, project-specific data collection involving large numbers of patients is achievable. Providing invaluable insight into the routine clinical management of metastatic colorectal cancer in the era of targeted therapies, this also creates a significant resource for research, including many questions not being addressed by clinical trials.

Parotid abscess in a late premature infant: a case report.

Parotid abscess is uncommon in neonates. It is frequently related to prematurity, prolonged gavage feeding and dehydration. We report a case of a late preterm infant who developed the classical manifestation of unilateral acute Staphylococcus aureus suppurative parotitis progressing to formation of abscess which responded to surgical drainage and antibiotic therapy.

The potential value of faecal lactoferrin as a screening test in hospitalized patients with diarrhoea.

BACKGROUND: Nosocomial diarrhoea is common and its investigation carries a significant healthcare cost. This study aimed to determine the utility of faecal lactoferrin (FL), a readily measurable marker of intestinal inflammation, in hospitalized patients with diarrhoea. METHODS: FL was quantified in consecutive faecal samples submitted to a hospital pathology laboratory. Patient data were extracted from hospital records. Receiver-operator curve (ROC) analysis was performed in a subset of patients where a decision about low or high likelihood of inflammation could be confidently made. Multivariate analyses were performed to identify associations with an elevated FL. Cost analyses were also performed. RESULTS: A total of 511 faecal samples from 433 patients (48% male, median age 67 years) was studied. Median FL concentration was 3.4 µg/mL (range 0-288). ROC analysis indicated an optimal cut-off value of 1.25 µg/mL (sensitivity 92%, specificity 97%, negative predictive value 97%) compared with the manufacturer's cut-off of 7.25 µg/mL (60%, 66% and 85% respectively). Multivariate analysis at the lower cut-off minimized potentially confounding variables. Proton pump inhibitor use independently increased (OR 2.3, 95% CI 1.5-3.8) and current smoking reduced (0.61, 0.38-0.99) the likelihood of an elevated FL. Only one out of 32 bacteriological positive samples would have been missed if FL was instituted as a screening test prior to microbiological assessment, which could have reduced laboratory-related costs by up to 56%. CONCLUSION: In hospitalized patients, a normal FL effectively excludes inflammatory diarrhoea and is proposed as a screening test prior to microbiological assessment of faeces. Prospective evaluation of this approach is warranted.

Insulin-like growth factor-1 promoter polymorphisms and colorectal cancer: a functional genomics approach.

RATIONALE: Insulin-like growth factor-1 (IGF1) has been proposed to mediate the obesity-related carcinogenic effects of "Western lifestyle". While genetic factors explain at least half of inter-individual IGF1 variation, the IGF1 polymorphisms hypothesised to underlie the variation in cancer incidence rates remain ill-defined. METHODS: We used a comparative genomics approach to identify putative regulatory polymorphisms in the IGF1 promoter region within a rapidly westernising population, the Singapore Chinese. Association of IGF1 genotype with colorectal cancer risk was assessed among 298 colorectal cancer cases and 1142 controls nested within the Singapore Chinese Health Study. RESULTS: We identified a common (minor allele frequency = 0.36) single-nucleotide polymorphism (SNP), IGF1-2995 C/A, within a consensus domain for an octamer binding factor (Oct1/Oct2) transcription factor binding site. Possession of one or two copies of the minor allele (genotypes AA and CA) conferred an approximate 40% decrease in risk in comparison to genotype CC (odds ratio, 0.59; 95% confidence interval, 0.45 to 0.77). This association was stronger for colon cancer than for rectal cancer (p(heterogeneity)<0.001) and for those who were physically active versus inactive (p(interaction) = 0.05). Models including other previously identified promoter polymorphisms did not provide a better prediction of colorectal cancer risk. CONCLUSIONS: Our results support the hypotheses that IGF1 plays a role in colonic carcinogenesis and that genetically inherited variation in IGF1 expression influences risk of colorectal cancer.

Comparison of range of motion after standard and high-flexion posterior stabilised total knee replacement.

The purpose of this study was to compare the range of motion after standard version posterior stabilised TKR and high-flexion version TKR in patients receiving bilateral total knee replacement. Thirty-five patients were recruited. The range of motion of the knees was measured clinically with a goniometer in both the pre-operative period and the most recent follow-up. It was found that the pre-operative range of motion was comparable in the two groups. The average post-operative flexion was 105 degrees +/- 13 degrees in the standard version group and 106 degrees +/- 14 degrees in the high-flexion design group (p = 0.201, paired t-test; beta error = 0.073). A slight loss in flexion was observed in the standard version group (0.5 degrees ) as opposed to a slight gain in the high-flexion design group (2 degrees ). However, this was not statistically significant (p = 0.251, paired t-test; beta error = 0.105).

Trace metals and organochlorines in the bamboo shark Chiloscyllium plagiosum from the southern waters of Hong Kong, China.

The bamboo shark Chiloscyllium plagiosum is an abundant benthic species along the shallow continental shelf of Southeast Asia. It is commonly taken by fishermen in China, India, Taiwan and Thailand for human consumption. This study measured trace metal and organochlorine concentrations in C. plagiosum collected from the southern waters of Hong Kong, China. Metals (Ag, Cd, Cr, Cu, Mn, Ni, Pb and Zn) were measured in three different tissues: dorsal muscle, spleen and liver. Polychlorinated biphenyls (PCBs) and chlorinated pesticides in the dorsal muscle were identified and quantified using gas chromatography. Metal concentrations varied among the three different tissues, with liver having higher levels of Ag and Cd, and spleen possessing higher levels of Cu and Mn. Both Ni and Pb in all tissues were below the detection limit. Tissue concentrations of Cr, Cu, Mn and Zn generally decreased with increasing body weight whilst no significant concentration-size relationship was found for other metals. In muscle tissues, total PCBs ranged from 1.056-4.771 ng/g (wet wt.) with a median of 1.801 ng/g, while total DDTs ranged from 0.602-23.55 ng/g with a median of 1.109 ng/g, in which p,p'-DDE was the predominant metabolite. Levels of total hexachlorohexanes and cyclodienes were low. The pesticide p,p'-DDT was the only compound found to be positively correlated with body weight, indicating temporal bioaccumulation of this compound. Zn concentrations in the muscle of C. plagiosum were comparatively higher than recorded in other shark species, however, concentrations of other metals and organochlorines were relatively low. C. plagiosum feeds primarily on polychaetes, shrimps and small fishes, and thus is unlikely to contain levels of contaminants of human health concern.

Sediment TCDD-EQs and EROD and MROD activities in Ranid frogs from agricultural and nonagricultural sites in Michigan (USA).

In vitro studies have demonstrated atrazine-mediated induction of 7-ethoxyresorufin O-deethylase (EROD) activity. EROD is an enzyme active in the metabolism of many compounds, including many xenobiotics. These studies have suggested that atrazine may affect reproductive function by altering steroid metabolism. The goal of this study was to determine whether relationships could be detected between measured atrazine concentrations in surface waters and the liver-somatic index (LSI) and EROD and 7-methoxyresorufin O-deethylase (MROD) activities in the livers of ranid frogs. In addition, sediment dioxin toxic equivalents (TCDD-EQs) were determined using the H4IIE-luc cell bioassay. Adult and juvenile green frogs (Rana clamitans), bullfrogs (R. catesbeiana), and Northern leopard frogs (R. pipiens) were collected from areas with extensive corn cultivation and areas where there was little agricultural activity in south central Michigan in the summer of 2003. Atrazine concentrations at nonagricultural sites ranged from less than the limit of quantification (0.17 microg atrazine/L) to 0.23 microg atrazine/L and did not exceed 1.2 microg atrazine/L at agricultural sites. Sediment TCDD-EQs were measurable only at one agricultural site. Of the measured parameters, only LSI values in adult male frogs differed significantly between agricultural and nonagricultural sites, with greater values observed at agricultural sites. In green frogs, EROD and MROD activities were measurable in both adult and juvenile frogs and were similar among sites. Median EROD activities ranged from 13 to 21 pmol/min/mg protein in adult male green frogs and from 5 to 13 pmol/min/mg protein in adult female green frogs. Juvenile frogs had greater EROD and MROD activities than adult frogs. Bullfrogs and leopard frogs had greater activities than did green frogs. Atrazine concentrations were significantly and negatively correlated with MROD activity in adult male green frogs (Spearman R = -0.800). LSI and EROD and MROD activities of adult female or juvenile green frogs were not significantly correlated with atrazine concentrations. These results suggest that atrazine does not appear to have a consistent association with EROD or MROD activities in wild-caught green frogs.

Organochlorine insecticides in mudflats of Hong Kong, China.

Organochlorine (OC) insecticides were measured in different environmental compartments (including seawater, sediment, and biota) at six sites within the Mai Po Marshes Nature Reserve (MPMNR) and at one site in A Chau (AC) in Hong Kong in June 2002 (wet season) and January 2003 (dry season). MPMNR is a Wetland of International Importance (Ramsar site) situated in the western part of Hong Kong, whereas AC is a relatively remote island in Starling Inlet on the eastern side of the New Territories of Hong Kong. Generally, concentrations of OC insecticides in water, sediment, and biota were greater at MPMNR than at AC. Hexachlorobenzene, dichloro-diphenyl-trichloroethane, and hexachlorocyclohexanes were detected in all samples collected from MPMNR. Preliminary risk assessments were performed by comparing the measured concentrations of OCs in different environmental compartments with the corresponding guidelines promulgated by various environmental protection authorities. Concentrations of some OCs in sediments from certain locations in MPMNR were consistently greater than their corresponding sediment guideline values. These results suggest that the sediment OC concentrations in the sediments of MPMNR might pose a risk to aquatic organisms. Despite this, concentrations of OCs in biota samples were much lower than the relevant guideline values promulgated by government agencies to protect the health of human consumers. It is postulated that the management practices adopted at MPMNR have been effective in limiting the bioaccumulation window (duration) for OCs. This situation may have been aided by a frequent exchange of water between the tidal shrimp ponds at MPMNR and the open sea, again attributable to management practices. The low-cost maintenance practices adopted at MPMNR may potentially be applicable to wetlands in other southeastern Asian countries, thus allowing sustainable fishery production and wildlife conservation.

Risks posed by trace organic contaminants in coastal sediments in the Pearl River Delta, China.

Local marine environments in China's Pearl River Delta (PRD), the most rapidly developing region in one of the world's fastest growing economies, have been experiencing significant environmental stress during the past decades. This investigation was conducted to determine the status and trends of persistence organic pollutants (POPs) such as polycyclic aromatic hydrocarbons (PAHs), petroleum hydrocarbons (PHCs), polychlorinated biphenyls (PCBs), organochlorine (OC) pesticides and dioxin-related compounds in marine sediments collected from sixteen coastal stations in the Pearl River Delta (PRD) in March 2003. Elevated concentrations of PAHs (94-4300 ng/g), PCBs (6.0-290 ng/g), PHCs (14-150 microg/g), and DDTs (1.4-600 ng/g) were detected in sediment samples. In addition, 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD)-like activities in the sediment samples were estimated to range from 0.3 to 440 pg TCDD-EQ/g. Sediments collected from Xiashan contained the greatest concentrations of trace organic contaminations amongst all the sampling stations in the present study. The degree of trace organic contamination was, in general, more severe at stations situated along the west shores of the PRD than their counterparts in the east. A preliminary assessment was performed to examine the probable risks to the marine ecosystem due to POPs. The results showed that OC pesticide contamination in the PRD was particularly serious and might pose a threat to the health of the marine inhabitants.

Estrogenic and dioxin-like activities and cytotoxicity of sediments and biota from Hong Kong mudflats.

Persistent organic pollutants, such as organochlorine insecticides and polychlorinated biphenyls (PCBs), were measured in several environmental matrices including aerial deposition, seawater, sediment, and biota in two important coastal wetlands of Hong Kong, China. Specifically, samples were collected from within the Mai Po Marshes Nature Reserve (Mai Po), an internationally acclaimed wetland situated in the northwestern part of the New Territories of Hong Kong, and A Chau in Starling Inlet, a relatively remote island on the eastern side of Hong Kong. Hexachlorobenzene, dichlorodiphenyltrichloroethanes, and hexachlorocyclohexanes were detected in all samples collected from Mai Po. Environmental endocrine disruptors (including dioxin-like compounds and estrogenic chemicals), measured by the use of cell-based chemical activated luciferase expression assays, were found to occur at concentrations that might pose a risk to the ecologic systems in Mai Po. Dioxin-like PCBs were detected at small concentrations in some of the samples. Concentrations of 2,3,7,8 tetrachlorodibenzo-p-dioxin equivalents (TEQs) were primarily related to the relatively great concentrations (>100 ng/g dry weight) of high molecular-weight polycyclic aromatic hydrocarbons in sediments, whereas the relative proportion of TEQs contributed by nonortho-substituted PCBs was small. Polar compounds primarily contributed estrogen equivalents, which were measured in sediments. Significant concentrations of cytotoxic compounds were detected in fish samples collected from the Mai Po but not in fish collected from A Chau.