Biological and chemical factors of importance in the bioaccumulation and trophic transfer of persistent organochlorine contaminants in Arctic marine food webs

Recent studies of arctic marine food webs have provided detailed insights regarding the biological and chemical factors that influence the bioaccumulation and trophic transfer of persistent organochlorine (OC) contaminants in aquatic systems. The present paper summarizes the recent literature with an emphasis on identifying important ecological factors for explaining variability of OC concentrations among organisms. The Arctic ecosystem has a number of unique attributes, including long food chains, reduced diversity of species, similar food webs across the entire region, and limited influence from pollution point sources. Lipid content, body size, age, gender, reproduction, habitat use, migration, biotransformation, seasonal changes in habitat conditions, feeding ecology, and trophic position have all been demonstrated to influence OC concentrations and bioaccumulation in arctic marine biota. The relative importance of each factor varies among OCs and organisms. Diet or trophic level is the dominant factor influencing OC concentrations and dynamics in seabirds and marine mammals, although biotransformation can significantly influence nonrecalcitrant OCs, such as hexachlorocyclohexane isomers. Dietary accumulation of OCs is also an important route of exposure for arctic fish and zooplankton, and biomagnification of OCs may also occur among these organisms. To date, only limited attempts have been made to model trophic transfer of OCs in the arctic marine food web. Although models developed to assess OC dynamics in aquatic food webs have included some biological variables (e.g., lipid content, feeding rate, diet composition, and growth rate), selection of processes included in these models as well as their mathematical solutions and parameterization all introduce simplification. This reduces biological validity of the models and may be particularly problematic in a highly seasonal environment, such as the Arctic Ocean.     

Women's experiences of the gynecologic examination: factors associated with discomfort

BACKGROUND: The aim of this study was to evaluate how women experience the gynecologic examination and to assess possible factors associated with experiencing discomfort during the gynecologic examination. METHODS: Consecutive patients visiting the Department of Obstetrics and Gynecology at Glostrup County Hospital, Denmark, were invited to participate in the study, and received a postal questionnaire that included questions about the index visit, obstetric and gynecologic history and sexual abuse history. The response rate was 80% (n = 798). The degree of discomfort during the gynecologic examination was indicated on a scale from 0 to 10. Experiencing discomfort was defined as a score of 6 or more, based on the 75th percentile. RESULTS: Discomfort during the gynecologic examination was strongly associated with a negative emotional contact with the examiner and young age. Additionally, dissatisfaction with present sexual life, a history of sexual abuse and mental health problems such as depression, anxiety and insomnia were significantly associated with discomfort. CONCLUSION: The emotional contact between patient and examiner seemed to have great importance when focusing on discomfort during the gynecologic examination. Furthermore, we found that discomfort was associated with a number of factors that are seldom known to the gynecologists, such as sexual abuse history, mental health problems and patients' sexual life. Gynecologists need to focus on the emotional contact and to reevaluate issues for communication before the examination.     

Growth of cultured porcine retinal pigment epithelial cells

PURPOSE: To establish and characterize cultures of porcine retinal pigment epithelial (pRPE) cells in order to produce confluent monolayers of cells for transplantation. METHODS: Primary pRPE cell cultures were established. Cell morphology was assessed by phase contrast and electron microscopy. Growth was determined by the crystal violet dye uptake assay. DNA synthesis and content were measured by incorporation of 3H-thymidine and flow cytometry. RESULTS: This primary culture resulted in cells with well-preserved morphology that could be propagated in up to six passages. The deterioration observed over time in cultures was not due to a constant high rate of cell turnover as postconfluency cell proliferation was limited. However, a large fraction of the cells had a high DNA content despite a lack of active DNA synthesis. CONCLUSIONS: The present method yields pRPE cells of high purity and proliferative capacity with preserved epithelial phenotype. However, aberrant DNA profiles and the deterioration of cell morphology observed over time in this graft material represent serious problems in RPE transplantation.     

Identification of interactive loci linked to insulin and leptin in mice with genetic insulin resistance

Mice double heterozygous (DH) for deletion of insulin receptor and insulin receptor substrate-1 are lean, insulin resistant, and have a phenotype that strongly depends on the genetic background of the mouse. On the C57BL/6 (B6) background, DH mice develop marked hyperinsulinemia and diabetes, whereas on the 129S6 background, DH mice exhibit only mild elevations of insulin and remain free of diabetes. F2 male mice created by an intercross between these two strains exhibit a 60% incidence of diabetes and a bell-shaped distribution of insulin levels as related to glucose, reminiscent of that in humans with type 2 diabetes. These mice also exhibit a wide range of leptin levels as related to body weight. A genome-wide scan of F2 mice reveals a quantitative trait locus (QTL) related to hyperinsulinemia on chromosome 14 (D14Mit55) with a peak logarithm of odds (LOD) score of 5.6, accounting for up to 69% of this trait. A QTL with a LOD score of 3.7 related to hyperleptinemia is present on chromosome 7 at D12Mit38 (a marker previously assigned to chromosome 12) in the area of the uncoupling protein 2/3 gene cluster. This locus also interacts synergistically with D14Mit55 in development of hyperinsulinemia and with a QTL on chromosome 12 (D12Mit231) related to hyperglycemia. These data demonstrate how multiple genetic modifiers can interact and influence the development of diabetes and the phenotype of animals with genetically programmed insulin resistance and provide evidence as to the location and nature of these genes.     

Do impotent men with diabetes have more severe erectile dysfunction and worse quality of life than the general population of impotent patients? Results from the Exploratory Comprehensive Evaluation of Erectile Dysfunction (ExCEED) database

OBJECTIVE: Little is known regarding how diabetic men with erectile dysfunction (ED) differ from the general population of impotent men. The primary objective of this study was to compare disease-specific health-related quality of life (HRQOL) and severity of ED in impotent men with and without diabetes. RESEARCH DESIGN AND METHODS: Validated functional and HRQOL questionnaires (including the International Index of Erectile Function, the Sexual Self-Efficacy Scale, and the Psychological Impact of Erectile Dysfunction scales) were administered to patients in an ED disease registry. Men with ED and a history of diabetes (n = 20) were compared with men with ED and no history of diabetes (n = 90) at baseline and at the 12-month follow-up. RESULTS: Diabetic impotent men reported worse erectile function and intercourse satisfaction at baseline, and ED had a greater impact on their emotional life. Diabetic men with ED had significantly different trends over time in the Erectile Function (P < 0.001), Intercourse Satisfaction (P < 0.013), Sexual Desire (P < 0.016), Overall Satisfaction (P < 0.023), and the Sexual Experience-Psychological Impact domains (P < 0.002). In addition, there was a trend toward a difference over time in the Emotional Life-Psychological Impact domain (P < 0.067). CONCLUSIONS: Impotent men with diabetes present with worse ED than nondiabetic men with ED, resulting in worse disease-specific HRQOL in the diabetic men. Although diabetic patients initially respond well to ED treatment, responses do not appear to be durable over time. Therefore, clinicians must provide longer-term follow-up when treating ED in diabetic patients.     

Photodynamic therapy with topical methyl‐ and hexylaminolevulinate for prophylaxis and treatment of UV‐induced SCC in hairless mice

Please cite this paper as: Photodynamic therapy with topical methyl‐ and hexylaminolevulinate for prophylaxis and treatment of UV‐induced SCC in hairless mice. Experimental Dermatology 2010; 19 : e166–e172. Abstract Background: Hexyl aminolevulinate (HAL) is a long‐chained 5‐aminolevulinic acid‐ester that has been proposed as a novel photosensitizing agent to methyl aminolevulinate (MAL) in topical photodynamic therapy (PDT). The more lipophilic HAL, may improve treatment outcome for non‐melanoma skin cancer. Objective: To compare the prophylactic and therapeutic effects of HAL‐ and MAL‐PDT for ultraviolet‐induced squamous cell carcinomas (SCCs) in hairless mice. Methods: Mice (n = 249) were irradiated with solar UV‐radiation (UVR) until SCC occurred. Before any skin changes developed, two prophylactic PDT treatments were given, using creams of HAL (2%, 6%, 20%) or MAL (20%) followed by illumination (632 nm, Aktilite, Photocure). Two therapeutic PDT‐treatments were given by randomization to the first developed SCC of 1 mm. Primary end‐points were time to first SCC of 1 mm and complete SCC clearance. Secondary end‐points were time to SCC‐recurrence, PpIX fluorescence and skin reactions to PDT. Results: The median time to first SCC was significantly longer for mice treated with prophylactic HAL‐PDT (2%, 6% and 20% HAL, 264 days) and MAL‐PDT (20% MAL, 269 days) than mice exposed to UVR (186 days) and UVR + placebo‐PDT (199 days) (P < 0.0001). The therapeutic efficacy of HAL‐ and MAL‐PDT showed cure rates of 23–61.5% (P = 0.11). Similar PpIX fluorescence intensity and severity of clinical reactions were seen for HAL‐ and MAL‐groups, although mice developed more intense hyper‐pigmentation when treated with 20% MAL‐PDT compared with 2% HAL‐PDT. Conclusions: PDT with HAL (2%, 6% and 20%) and MAL (20%) is equally effective to prevent and treat UV‐induced SCC in hairless mice.     

Activity of creatine kinase in sera from healthy women,carriers of Duchenne muscular dystrophy and cord blood,determined by the “European” recommended method with NAC-EDTA activation

Creatine kinase activity has been measured at 37°C in sera from healthy women, carriers of Duchenne muscular dystrophy and cord blood, with activation by N-acetyl cysteine (NAC) and EDTA as recommended by several European committees on standardisation. The upper limit of the reference range for healthy women was found to be 170 U/1. The distributions of creatine kinase activities in healthy and carrier women have been used to calculate probability of carrier status as a function of creatine kinase activity. Although the range of creatine kinase activities in normal cord blood is wide, the data provide a basis for interpretation when Duchenne muscular dystrophy is suspected.