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Taenia solium taeniasis and cysticercosis in three communities in north Vietnam.

OBJECTIVES: (1) To investigate the response to a serum antigen-detecting ELISA for cysticercosis and a stool coproantigen test for taeniasis in two rural communities (mountainous and coastal areas) and one group of (peri-)urban factory workers; and (2) to examine clinical features of human cysticercosis in northern Vietnam. METHODS: Villagers and factory workers and their families were informed and invited to participate in the study. Blood and faecal samples were collected from the participants and a simple questionnaire on taeniasis/cysticercosis completed. Serum was examined for the presence of circulating cysticercus antigen by a monoclonal-based sandwich ELISA. Ag-ELISA positive persons underwent a clinical examination and a computed tomography (CT) scan. Stool samples were examined microscopically for the presence of Taenia eggs and for copro-antigens. Tapeworms were identified following therapeutic expulsion using morphology and PCR-RFLP. RESULTS: Circulating cysticercus antigens, suggesting active infection, were detected in 5.3% (16/303), 0.6% (1/175) and 0.0% (0/229) of the sampled individuals from the mountainous, coastal and urban regions, respectively. Clinical examination and CT scan of the cysticercus antigen positive persons showed that active cysticercosis did not cause severe disease in most cases. Taenia copro-antigens were found in 0.3% (1/297), 1.8% (3/166) and 0.0% (0/228) of the stool samples from the mountainous, coastal and urban communities, respectively. Three tapeworms were expelled after treatment: two Taenia solium and one Taenia saginata. CONCLUSION: This survey points to a focal distribution of taeniasis/cysticercosis and suggests that human cysticercosis is rather acquired due to close contact with a T. solium carrier and self-infection, than through infection from the environment.

Adolescent↗

A radial basis classifier for the automatic detection of aspiration in children with dysphagia.

BACKGROUND: Silent aspiration or the inhalation of foodstuffs without overt physiological signs presents a serious health issue for children with dysphagia. To date, there are no reliable means of detecting aspiration in the home or community. An assistive technology that performs in these environments could inform caregivers of adverse events and potentially reduce the morbidity and anxiety of the feeding experience for the child and caregiver, respectively. This paper proposes a classifier for automatic classification of aspiration and swallow vibration signals non-invasively recorded on the neck of children with dysphagia. METHODS: Vibration signals associated with safe swallows and aspirations, both identified via videofluoroscopy, were collected from over 100 children with neurologically-based dysphagia using a single-axis accelerometer. Five potentially discriminatory mathematical features were extracted from the accelerometry signals. All possible combinations of the five features were investigated in the design of radial basis function classifiers. Performance of different classifiers was compared and the best feature sets were identified. RESULTS: Optimal feature combinations for two, three and four features resulted in statistically comparable adjusted accuracies with a radial basis classifier. In particular, the feature pairing of dispersion ratio and normality achieved an adjusted accuracy of 79.8 +/- 7.3%, a sensitivity of 79.4 +/- 11.7% and specificity of 80.3 +/- 12.8% for aspiration detection. Addition of a third feature, namely energy, increased adjusted accuracy to 81.3 +/- 8.5% but the change was not statistically significant. A closer look at normality and dispersion ratio features suggest leptokurticity and the frequency and magnitude of atypical values as distinguishing characteristics between swallows and aspirations. The achieved accuracies are 30% higher than those reported for bedside cervical auscultation. CONCLUSION: The proposed aspiration classification algorithm provides promising accuracy for aspiration detection in children. The classifier is conducive to hardware implementation as a non-invasive, portable "aspirometer". Future research should focus on further enhancement of accuracy rates by considering other signal features, classifier methods, or an augmented variety of training samples. The present study is an important first step towards the eventual development of wearable intelligent intervention systems for the diagnosis and management of aspiration.

Journal Article↗

Development of a passive sampler to measure personal exposure to gaseous PAHs in community settings.

A sensitive, simple, and cost-effective passive sampling methodology was developed to quantify personal exposure to gaseous polycyclic aromatic hydrocarbons (PAHs). A Fan-Lioy passive PAH sampler (FL-PPS) is constructed from 320 sections of 1-cm long SPB-5 GC columns (0.75-mm i.d. and 7-microm film thickness), similar to a mini-honeycomb denuder. Given the unique feature of the GC column stationary phase, gaseous PAHs are collected on the inner surfaces of the columns by molecular diffusion and thermally desorbed to GC/MS for analysis. The sampling rates of FL-PPS were determined in the laboratory using a controlled test atmosphere containing eight PAHs for a range of face velocity, temperature, relative humidity, PAH concentration, and sampling duration. The sampling rate (mean, %RSD, cm3/min) was 26.7 (21%) for acenaphthylene, 37.6 (25%) for acenaphthene, 56.2 (13%) for fluorene, 49.1 (25%) for phenanthrene, 62.7 (22%) for anthracene, 65.4 (24%) for fluoranthene, and 64.4 (18%) for pyrene over a sampling duration of 8-48 h. The sampling rate for naphthalene was approximately 14.1 (12%) cm3/min over a sampling period of 8 h but decreased along with an increase of sampling time. The effects of temperature, humidity, face velocity, and PAH concentration on the sampling rate were not significant for all the compounds tested. A reasonable agreement (<30%) was obtained for most compounds measured by FL-PPS and a conventional active PAH sampling method colocated side-by-side in the field, but a sampling time of 24 h or longer was required for detection of less abundant PAHs in community settings.

Air Pollutants↗

Bacterial communities in acidic and circumneutral streams.

The relationship between pH and the abundance and activity of bacteria in streams was examined as part of a study of the effect of acidification on stream communities. Of the bacterial communities examined, the epilithic community appeared to be the most significantly affected by acidification. Microbial biomass, as quantified by measuring the ATP level, on rock surfaces was significantly correlated with pH. Also, bacterial production by the epilithic bacteria, indicated by incorporation of tritiated thymidine into DNA, was always higher at high-pH sites than at low-pH sites of the same stream order and elevation. Bacterioplankton concentrations varied between 0.53 x 10 and 9.42 x 10 cells . ml in the first- to fourth-order streams examined. The bacterioplankton concentration in one sample from a spring was 0.17 x 10 cells . ml. Bacterioplankton concentrations were not correlated with pH but were significantly correlated with seston concentrations. The correlation with seston is a result of increases in particle-associated bacteria at high seston concentrations. The proportion of bacterioplankton attached to particles varied from 0 to 70%. Bacterial numbers and production in the sediments were significantly correlated with the organic content of the sediment rather than with the pH of the overlying water. Thus, reduced abundance and activity of bacteria as a result of acidification could be detected only for the relatively active community on rock surfaces; this community was exposed to the low pH because of the unbuffered nature of its environment.

Journal Article↗

[Comparison of the number of Norovirus genome copies in patients and healthy persons].

In viral gastroenteritis outbreaks occurred by Norovirus (NV), NV was detected not only from patients but also from healthy persons who have taken the same food, and also detected from healthy staff members working at community places such as hospital, school and nursing home. The number of fecal NV genome copies of patients, healthy persons and food handlers are examined by real-time PCR method, to investigate foodborne gastroenteritis and person to person transmission outbreaks. There is no significant difference on the number of NV genome copies in feces between patients, and NV-detected healthy persons. Those result indicate asymptomatic carrier of NV who were working as food handlers or staff members at community places will become an origin of food-borne gastroenteritis or person to person transmission outbreaks.

Caliciviridae Infections↗

Helicobacter pylori and dyspepsia: a population-based study of the organism and host.

OBJECTIVE: The role of Helicobacter pylori (HP) infection in dyspepsia in the absence of peptic ulcer remains controversial. Specific attributes of the organism or the host response may be important. We aimed to determine whether HP infection overall, CagA status, serum gastrin, or serum pepsinogen levels are associated with dyspepsia in the community. METHODS: A self-report bowel disease questionnaire was mailed to a random sample of Olmsted County, Minnesota residents, aged 20-50 yr. All respondents who reported symptoms of dyspepsia or irritable bowel syndrome (cases) and all respondents without significant GI symptoms (controls) were invited to participate (n = 260). They were each assessed by a physician and their medical records reviewed. Serum was obtained to measure HP and CagA antibodies, pepsinogen I and II levels, and basal serum gastrin using validated assays. RESULTS: Of the 148 (57%) subjects who agreed to participate, 36 had dyspepsia (17 had ulcer-like dyspepsia), 35 had irritable bowel syndrome (IBS) without dyspepsia, and 77 were asymptomatic. The proportion who were seropositive for HP were 17% in dyspepsia (24% in ulcer-like dyspepsia), 20% in IBS, and 12% in asymptomatic controls. HP was not associated with dyspepsia, ulcer-like dyspepsia, or IBS after adjusting for age. Pepsinogen levels and serum gastrin were not associated with any of the conditions studied. However, CagA antibody positivity was associated with IBS (p < 0.05), and a borderline statistically significant association with dyspepsia was detected (p = 0.08). CONCLUSIONS: In this community, HP infection overall does not seem to explain dyspepsia, although the role of CagA-positive HP strains deserve further study.

Adult↗

Water quality and macroinvertebrate community response following pesticide applications in a banana plantation, Limon, Costa Rica.

Pesticides used in banana production may enter watercourses and pose ecological risks for aquatic ecosystems. The occurrence and effects of pesticides in a stream draining a banana plantation was evaluated using chemical characterization, toxicity testing and macrobenthic community composition. All nematicides studied were detected in the surface waters of the banana plantation during application periods, with peak concentrations following applications. Toxicity tests were limited to the carbofuran application and no toxicity was observed with the acute tests used. However, since pesticide concentrations were generally below the lowest LC50 value for crustaceans but above calculated aquatic quality criteria, there remains a risk of chronic toxicity. Accurate ecological assessments of pesticide use in banana plantations are currently limited by the lack of local short-term chronic toxicity tests and tests using sensitive native species. Relatively constant levels of four pesticides (imazalil, thiabendazole, chlorpyrifos and propiconazole), which had toxic effects according to the 96h hydra and 21d daphnia chronic test, were recorded in the effluent of the packing plant throughout the study, indicating that the solid waste trap used in this facility was not effective in eliminating toxic chemicals. Certain taxa, such as Heterelmis sp. (Elmidae), Heteragrion sp. (Megapodagrionidae, Odonata), Caenis sp. (Caenidae, Ephemerotera), and Smicridea sp. (Hidropsychidae, Trichoptera), were more abundant at reference sites than in the banana farm waters, and may be good candidates for toxicity testing. Multivariate analyses of the macroinvertebrate communities clearly showed that the banana plantation sites were significantly different from the reference sites. Moreover, following the pesticide applications, all the banana plantation sites showed significant changes in community composition, with the same genera being affected at all sites and for all pesticides (terbufos, cadusafos and carbofuran). Consequently, the results presented here show that multivariate analysis of community composition was more sensitive in distinguishing pesticide effects than the toxicity tests and richness and composition measures used. We conclude that monitoring macroinvertebrate communities can be a powerful tool in the assessment of ecological effects of banana production.

Agriculture↗

Identifying the elderly at risk for malnutrition. The Mini Nutritional Assessment.

In more than 10,000 elderly persons, the mean prevalence of malnutrition is 1% in community-healthy elderly persons, 4% in outpatients receiving home care, 5% in patients with Alzheimer's disease living at home, 20% in hospitalized patients, and 37% in institutionalized elderly persons. In community-dwelling elderly persons, the MNA detects risk of malnutrition and life-style characteristics associated with nutritional risk while albumin levels and the BMI are still in the normal range. In outpatients and in hospitalized patients, the MNA is predictive of outcome and cost of care. In home care patients and nursing home residents, the MNA is related to living conditions, meal patterns, and chronic medical conditions and allows targeted intervention. The MNA has been used successfully in follow-up evaluation of outcome, nutritional intervention, nutritional education programs, and physical intervention programs in elderly persons. The MNA-SF allows quick screening to determine a person's risk of malnutrition. Early detection of malnutrition is important to allow targeted nutritional intervention and should be a key component of the geriatric assessment. The MNA test is a simple, noninvasive, well-validated screening tool for malnutrition in elderly persons and is recommended for early detection of risk of malnutrition. The MNA, as a two-step procedure (screening with the MNA-SF followed by assessment, if needed, by the full MNA), is reliable and can be easily administered by general practitioners and by health professionals at hospital or nursing home admission for early detection of risks of malnutrition. The MNA has the following characteristics: * The MNA is a two step procedure: (1) the MNA-SF to screen for malnutrition and risk of mainutrition; (2) assessment of nutritional status with the full MNA. * The MNA is an 18-item questionnaire comprising anthropometric measurements (BMI, mid-arm and calf circumference, and weight loss) combined with a questionnaire regarding dietary intake (number of meals consumed, food and fluid intake, and feeding autonomy), a global assessment (lifestyle, medication, mobility, presence of acute stress, and presence of dementia or depression), and a self-assessment (self-perception of health and nutrition). The MNA-SF comprises 6 items from the 18. * The MNA is well validated. It correlates highly with clinical assessment and objective indicators of nutritional status (albumin level, BMI, energy intake, and vitamin status). * A low MNA score can predict hospital-say outcomes in older patients and can be used to follow up changes in nutritional status. * Because of its validity in screening and assessing the risk of malnutrition, the MNA should be integrated in the comprehensive geriatric assessment. * In more than 10,000 elderly persons, the prevalence of undernutrition assessed by the MNA is 1% to 5% in community-dwelling elderly persons and outpatients, 20% in hospitalized older patients, and 37% in institutionalized elderly patients.

Aged↗

Identification of serious drug-drug interactions: results of the partnership to prevent drug-drug interactions.

OBJECTIVE: To develop a list of clinically important drug-drug interactions (DDIs) likely to be encountered in community and ambulatory pharmacy settings and detected by a computerized pharmacy system. DESIGN: Cross-sectional, one-time evaluation. SETTING: United States in fall 2001. PARTICIPANTS: An expert panel comprising two physicians, two clinical pharmacists, and an expert on DDIs. INTERVENTIONS: Systematic review of drug interaction compendia and published literature, ratings (on a 1 to 10 scale) of various clinical aspects of DDIs (e.g., clinical importance, quality and quantity of evidence, causal relationship, risk of morbidity and mortality), and a modified Delphi consensus-building process. MAIN OUTCOME MEASURE: Panelists' opinions about clinical importance of DDIs. RESULTS: The expert panel considered 56 DDIs. Of these, 28 had a mean clinical importance score of 8.0 or more. The ratings for clinical importance ranged from 3.2 to 9.6, with a mean +/- SD of 7.5 +/- 1.5 across the combinations examined. The mean score for the quality of literature suggesting the interaction exists ranged from 1.0 to 9.6, with a mean +/- SD of 5.8 +/- 2.5. In terms of substantiation of the interactions evaluated, the mean +/- SD rating was 6.3 +/- 2.2, with a range from 1.4 to 9.2. Through the modified Delphi process, the panel determined that 25 interactions were clinically important. CONCLUSION: Using an expert panel and a standard evaluation tool, 25 clinically important drug interactions that are likely to occur in the community and ambulatory pharmacy settings were identified. Pharmacists should take steps to prevent patients from receiving these interacting medications, and computer software vendors should focus interaction alerts on these and similarly important DDIs.

Community Pharmacy Services↗

Development and application of new nucleic acid-based technologies for microbial community analyses in foods.

Several challenges still persist in the analysis of microorganisms in foods, particularly in studies of complex communities. Nucleic acid-based methods are promising tools in addressing new questions concerning microbial communities. We have developed several new methods in the field of nucleic acid-based microbial community analyses. These methods cover both sample preparation and detection approaches. The sample preparation method involves simplified DNA purification using paramagnetic beads. As an extension of this method, the same paramagnetic beads are used for both cell separation and DNA purification. This enables full automation. The separate detection of viable and dead bacteria is a major issue in nucleic acid-based diagnostics. We have applied a living/dead dye that binds covalently to DNA and inhibits the PCR from dead cells. In addition, a DNA array-based detection assay has been developed. The assay combines the specificity obtained by enzymatic labeling of DNA probes with the possibility of detecting several targets simultaneously by DNA array hybridization. In combination with 16S rDNA amplification, this is a promising tool for community analyses. Also, we have developed a novel approach for multiplex quantitative PCR. The multiplex PCR has been combined with our DNA array-based detection method. Finally, we are now in the process of adapting a system for monitoring microbial growth and death in real-time through the tagging of bacteria with green fluorescent protein (GFP) combined with fluorescence detection using a high-resolution confocal laser scanner.

Bacteria↗

Payment for cancer prevention. Community and government perspectives.

PURPOSE: The development of a stronger interest in cancer prevention and early detection programs has led to the opportunity for mechanisms to provide adequate financial support at the individual, practitioner, and community levels. This discussion draws on the experiences of public health systems and emerging models for personal care to describe a framework for consideration of prevention and early detection funding, and to discuss the prospects of funding. OVERVIEW: Some prevention and early detection services are financed appropriately through individual payment mechanisms and can be covered in indemnity and capitated insurance plans. Population-based approaches to prevention do not fit this model, however, and need to be financed at the community level, through taxes or other shared financing schemes. CLINICAL IMPLICATIONS: Lack of public understanding of the differences between individual- and population-based prevention makes resource development difficult. Practitioners interested in such approaches need to join with others in the community to gain support. Long-term support of community efforts currently remains unclear. Although the actions identified are essential, they are not sufficient to support a comprehensive cancer prevention and detection program fully. The concerned clinician should become a part of the community-wide effort. This may be done individually, through participation on a local board of health or a hospital-based health promotion coalition. This also may be achieved through associations such as the local medical society or the local American Cancer Society.

Community Networks↗

[An episode of the prevention of cardiovascular risk factors by age and sex in the Community of Valencia].

OBJECTIVE: To typify the episodes of early detection of cardiovascular risk factors (CRF) and to calculate their frequency by age and sex groups. DESIGN: An observational, prospective and multi-centred study. SETTING: Twenty health centres distributed in the three provinces of the Community of Valencia. PATIENTS: Episodes of prevention of CRF in users of both sexes aged between 18 and 64 who, in the three years prior to the study, had undergone no CRF early diagnosis protocol. They were included by means of consecutive proposal with informed consent. MEASUREMENTS AND RESULTS: The diagnostic protocol of the Plan for Prevention of Cardiovascular Diseases (PPCVD) was applied. The variables analysed were: age, sex, number and duration of consultations, CRF diagnosed previously, and CRF diagnosed at the intervention. 632 episodes were analysed, with a mean 1.44 (CI: 1.39-1.49) consultations per episode and a mean duration of 10 minutes 53 seconds. At the start of the study 60.3% of the population did not have CRF, but after the intervention only 17.2% had no CRF diagnosed. CRF frequency after the intervention was: diabetes 4.5% (CI: 3.2-12.2), alcohol consumption 5.5% (CI: 2.2-13.1), hypertension 14.9% (CI: 7.7-22.2), obesity 30.8% (CI: 24.3-37.3), tobacco habit 33.2% (CI: 26.8-39.6), lipaemia 42.5% (CI: 36.6-48.5), and sedentary life-style 54.9% (CI: 49.6-60.2). CONCLUSIONS: CRF diagnosed most often after the intervention were: sedentary life-style, tobacco habit and obesity; and the least commonly diagnosed was alcohol consumption. The application of the PPCVD protocol was most effective in the youngest age-groups and women. The "episode" as a unit of analysis is a useful and feasible instrument for investigating the procedures and results of primary care preventive activities.

Adolescent↗

Mycobacterium ulcerans infection: control, diagnosis, and treatment.

The skin disease Buruli ulcer, caused by Mycobacterium ulcerans, is the third most common mycobacterial disease after tuberculosis and leprosy and mainly affects remote rural African communities. Although the disease is known to be linked to contaminated water, the mode of transmission is not yet understood, which makes it difficult to propose control interventions. The disease is usually detected in its later stages, when it has caused substantial damage and disability. Surgery remains the treatment of choice. Although easy and effective in the early stages of the disease, treatment requires extended excisions and long hospitalisation for the advanced forms of the disease. Currently, no antibiotic treatment has proven effective for all forms of M ulcerans infection and research into a new vaccine is urgently needed. While the scientific community works on developing non-invasive and rapid diagnostic tools, the governments of endemic countries should implement active case finding and health education strategies in their affected communities to detect the disease in its early stages. We review the diagnosis, treatment, and control of Buruli ulcer and list priorities for research and development.

Bacterial Vaccines↗

Assessment of MIST Alert, a commercial qualitative assay for detection of paralytic shellfish poisoning toxins in bivalve molluscs.

A recently developed commercial rapid test kit (MIST Alert) was assessed for determination of the presence of paralytic shellfish poisoning (PSP) toxins in shellfish. Several commercially important shellfish species obtained from the UK shellfish toxin monitoring program, containing a range of total PSP toxicities as determined by the mouse bioassay (MBA), were tested. The kit detected toxin in all samples containing the European Community tolerance level of 80 microg saxitoxin (STX) equivalents/100 g shellfish flesh as determined by the MBA. With one exception, the kit detected toxin in all samples that contained >40 microg STX equivalents/100 g according to the MBA. Among samples in which the MBA did not detect toxin, the kit disagreed in 25% of the tests, although further analysis by liquid chromatography (LC) and MBA of some samples confirmed the presence of toxins. These results suggest that MIST Alert may be suitable as an initial screen for PSP toxins as part of routine monitoring programs, thereby greatly reducing the number of MBAs. Trials were also performed by nonscientific personnel to evaluate the ease of use and interpretation of results obtained by MIST Alert. The results indicated that the kits could be readily used and accurately interpreted by individuals with no technical or scientific background.

Animals↗

Effect of permethrin-treated bed nets on the spatial distribution of malaria vectors in western Kenya.

The effect of insecticide (permethrin)-treated bed nets (ITNs) on the spatial distribution of malaria vectors in neighboring villages lacking ITNs was studied during a randomized controlled trial of ITNs in western Kenya. There was a trend of decreased abundance of Anopheles gambiae with decreasing distance from intervention villages both before (P = 0.027) and after (P = 0.002) introduction of ITNs, but this trend was significantly stronger after ITNs were introduced (P = 0.05). For An. funestus, no pre-intervention trend was observed (P = 0.373), but after the intervention, a trend of decreased abundance with closer proximity to intervention compounds developed (P = 0.027). Reduction in mosquito populations in villages lacking ITNs was most apparent in compounds located within 600 meters of intervention villages. Sporozoite infection rates decreased in control areas following the introduction of ITNs (P < 0.001 for both species), but no spatial association was detected between sporozoite rates and distance to nearest intervention village. We conclude that high coverage of ITNs is associated with a community-wide suppression of mosquito populations that is detectable in neighboring villages lacking ITNs, thereby affording individuals residing in these villages some protection against malaria.

Animals↗

Development and validation of a diagnostic microbial microarray for methanotrophs.

The potential of DNA microarray technology in high-throughput detection of bacteria and quantitative assessment of their community structures is widely acknowledged but has not been fully realised yet. A generally applicable set of techniques, based on readily available technologies and materials, was developed for the design, production and application of diagnostic microbial microarrays. A microarray targeting the particulate methane monooxygenase (pmoA) gene was developed for the detection and quantification of methanotrophs and functionally related bacteria. A microarray consisting of a set of 59 probes that covers the whole known diversity of these bacteria was validated with a representative set of extant strains and environmental clones. The potential of the pmoA microarray was tested with environmental samples. The results were in good agreement with those of clone library sequence analyses. The approach can currently detect less dominant bacteria down to 5% of the total community targeted. Initial tests assessing the quantification potential of this system with artificial PCR mixtures showed very good correlation with the expected results with standard deviations in the range of 0.4-17.2%. Quantification of environmental samples with this method requires the design of a reference mixture consisting of very close relatives of the strains within the sample and is currently limited by biases inherent in environmental DNA extraction and universal PCR amplification.

Bacteria↗

Organochlorine and heavy metal contaminants in wild mink in western Northwest Territories, Canada.

The mink (Mustela vision) is a top trophic level species that readily bioaccumulates environmental pollutants and is considered to be a sensitive indicator of ecosystem health. Spatial trends in levels of organochlorine and heavy metal contaminant burdens were determined from 1991 to 1995 for wild mink from western Northwest Territories (NWT), Canada. Tissue samples from 207 mink from seven communities were analyzed for residues of 63 organochlorines and 10 heavy metals. All groups of organochlorines were detected in mink livers at relatively low levels; maximum community means were 9.52 ng/g sigma DDT and 73.07 ng/g sigma PCB (sum of 43 congeners). There was a general trend of decreasing organochlorine burdens along a northerly or westerly gradient for some groups of compounds, primarily sigma DDT, sigma PCB, sigma chlordane and dieldrin. Toxic equivalents (TEQs) of mink liver tissue were low, with the maximum community mean of 0.28 pg/g wet weight (5.5 pg/g lipid weight). Levels of heavy metal burdens in liver and kidney tissues were found to be relatively low, with the exception of Hg, which was found at moderate levels. There was no obvious geographic trend to the pattern of heavy metal burdens. The available evidence suggests that long-range atmospheric transport is the main source of the organochlorine contaminants observed. Local conditions (geology, water and soil chemistry, diet, etc.) may determine heavy metal burdens. Levels of contaminants in NWT mink appear to be one to two orders of magnitude lower than levels observed to cause reproductive impairment, reduced survival of kits, or lethality in adult mink. In the western NWT mink may be the best indicator to assess trends in environmental contaminants and ecosystem health; periodic monitoring is recommended.

Animals↗

Delayed diagnosis and treatment of acoustic neuroma.

The records of 25 patients who underwent excision of acoustic neuroma between 1980 and 1987 were reviewed. All patients originated from southern New England. Facial nerve function was preserved in 92% of all patients, and 42% of patients with tumors less than 2.0 cm retained residual hearing postoperatively. These rates compare favorably with those found in larger series. Our series demonstrated that 60% of patients complained of hearing loss for longer than 2 years prior to tumor diagnosis. The mean duration of hearing loss prior to diagnosis was 4.2 years. Although sophisticated diagnostic methods were generally available, early detection of tumors did not occur, despite the early onset of auditory symptoms. The emergence of sophisticated computer-assisted diagnostic tests and the development of technologically advanced operative methods have reduced operative morbidity, but interestingly, have had little influence on early tumor diagnosis. Late detection of acoustic neuroma in an otherwise medically sophisticated community suggests the need for improved awareness among patients and their primary care providers. Failure of early detection may occur more commonly than generally appreciated, despite the availability of technologically advanced methods of diagnosis.

Adult↗