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P Dahl

Publications and source records attributed to P Dahl.

At least 19 recordsLinked to original sources
PubMed2006

[Retrospective evaluation of the results of the microbiological meat examination (MFU) from calves and cows].

The microbiological meat examination (MFU), consisting of a bacteriological analysis and a testing for antibiotic residues, is one of several additional analyses used for an edibility rating of carcasses made during meat inspection. Reasons for performing a microbiological meat examination and procedures in the laboratory are defined in the Swiss ordinance for meat examination (FUV). The aim of this study was to analyze the data of 313 microbiological meat examinations from calves and 2882 microbiological meat examinations from cows carried out at the Institute for Food Safety and Hygiene during a period of 8 years. Reasons for microbiological meat examinations as reported by the meat inspectors were mainly classified to the category of "inflammation and necroses" (FUV, Annex 4, Pt 1.2; calves: 73%, cows: 48%). As declarations of the age of the pathological-anatomical changes (that influences directly the probability of detection of pathogens) were generally missing, it is not surprising that the compliance between a particular pathological-anatomical change and a specific detection of pathogens is poor (calves: 19%, cows: 18% of all MFU). About 18% (calves) and 45% (cows) of the reasons for microbiological meat examinations did not correspond to one of the reasons mentioned in the ordinance for meat examination. However, according to the data set, some reasons require a microbiological meat examination due to an often-found specific detection of pathogens. Otherwise, a remarkable number of reasons mentioned were missing the link to bacteriological etiology. Moreover, 14% (calf) and 7% (cow) of microbiological meat examinations with the declaration "no pretreatment" as well as 15% (calf) and 11% (cow) of microbiological meat examinations without declaration showed a positive result in the testing for antibiotic residues.

Animals↗
PubMed1998

Case-control study on breast cancer and adipose tissue concentrations of congener specific polychlorinated biphenyls, DDE and hexachlorobenzene.

In a case-control study on 43 patients operated for invasive breast cancer (cases) and 35 patients operated for benign breast disease (controls) adipose tissue concentrations of polychlorinated biphenyls (PCBs), 1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene (DDE) and hexachlorobenzene (HCB) were investigated. Approximately 10 g of breast tissue free from tumour was taken and frozen until analysis. No significant difference for the sum of non co-planar PCBs or DDE was found between cases and controls. For postmenopausal women the odds ratio (OR) was increased for co-planar PCB #77 > 4.5 pg/g lipid (OR = 5.8, 95% confidence interval (CI) = 0.8-42), PCB #126 > 145 pg/g lipid (OR = 2.2, 95% CI = 0.2-18), PCB #169 > 90 pg/g lipid (OR = 7.8, 95% CI = 0.6-96), and for HCB > 40 ng/g lipid (OR = 1.9, 95% CI = 0.4-7.2) adjusted for age and parity. The risk increased further for postmenopausal women with oestrogen receptor positive tumours yielding for PCB #77 adjusted OR 33 (95% CI 1.8-588), PCB #126 OR not calculable (no unexposed cases), PCB #169 OR 8.6 (95% CI 0.5-136) and hexachlorobenzene OR 7.1 (95% CI 1.1-45). Also for the sum of PCB > 1230 ng/g lipid adjusted OR increased to 1.8 (95% CI 0.4-7.3) whereas the results were similar for DDE.

Adipose Tissue↗
PubMed1996

Influence of perinatal ochratoxin A exposure on the immune system in mice.

The mycotoxin ochratoxin A (OA) is a well-documented immunotoxic agent which affects both cellular and humoral immunity. In the present study, the effects of maternal exposure to single doses of OA during gestation or lactation were studied in Balb/c offspring. A single dose exposure of the dams to OA (500 micrograms/kg body weight) on day 16 of gestation resulted in decreased proliferation of splenic and thymic lymphocytes in response to mitogens in the pups at 15 days of age. Flow cytometry analysis of thymocyte subpopulations revealed lower percentages of mature CD4+ cells and higher percentages of immature, double-positive (CD4+CD8+) cells in the exposed pups. In contrast, a single exposure of the dams of OA on day 10 postpartum significantly increased the proliferative responsiveness of lymphocytes in the offspring when stimulated with B or T cell mitogens 3 days after the exposure. This effect was most prominent in the highest dose group (500 micrograms/kg body weight). The present results are in accordance with previous observations in rats, and show that the time of exposure significantly influences the immunotoxic effects of OA on the developing immune system in rodents.

Administration, Oral↗
PubMed1996

Increased concentrations of octachlorodibenzo-p-dioxin in cases with breast cancer--results from a case-control study.

Organochlorines are persistent and highly lipophilic environmental contaminants which bioaccumulate in the food chain. Some of these chemicals, 2,2-bis(p-chlorophenyl)-1,1,1-trichloroethane (DDT) and polychlorinated biphenyls (PCBs), have been suggested to be of significance in the aetiology of breast cancer. 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) is an anti-oestrogen in animal studies and should be thus lower the risk of breast cancer. The other isomers of polychlorinated dibenzo-p-dioxins (PCDDs) or the chemically related polychlorinated dibenzofurans (PCDFs) have not been tested regarding carcinogenesis of the breast. The purpose of this study was to investigate whether PCDDs or PCDFs influence the risk for breast cancer. Consecutive patients who underwent surgery for a breast disease between 1993 and 1995 were recruited for the study. Cases were 22 patients with infiltrative breast cancer and controls were 19 patients operated for a benign breast disease during the same time period. Approximately 10 g of breast tissue free from tumour was taken from the specimen and frozen until analysis. Fat was extracted, cleaned and analysed with a high-resolution gas chromatograph coupled to a high-resolution mass spectrometer. Median concentrations of octachlorinated dibenzo-p-dioxin (OCDD) were 598 (170-14,880) and 396 (103-1,847) pg/g lipid in the cases and in the controls, respectively. In a multivariate logistic regression analysis controlling for other risk factors for breast cancer increased odds ratio (OR) was obtained for OCDD: 401-1000 pg/g lipid yielded OR 3.8, 95% confidence interval (CI) 0.4-39, > 1000 pg/g lipid gave OR 5.2, CI 0.4-72. When the lipid OCDD variable was examined as a continuous risk factor there was a 1.09 (9%), CI 0.95-1.25, increase in the adjusted OR for breast cancer per 100 unit (pg/g lipid) increase in OCDD. No differences were found between cases and controls for the other six tested PCDDs. Mean concentration of TCDD was in the cases 3.6 (1.0-7.9) and in the controls 3.3 (1.1-6.3) pg/g lipid. For PCDFs no significant differences were found between cases and controls. The results were not changed if oestrogen or progesterone receptor status, S-phase fraction and DNA ploidy were considered. Breast tissue concentration of OCDD was increased in cancer patients, whereas the concentrations of other PCDDs and PCDFs were equal in cases and controls.

Adult↗
PubMed1996

A new scleral suction trephine for retrieval of corneoscleral donor tissue.

BACKGROUND: Removal of donor corneo-scleral shell from a cadaver, leaving the remainder of the eye in place, has become a popular technique. Manual removal can result in excessive trauma to the corneal endothelium or an uneven scleral rim. METHODS: We describe a new technique for corneal retrieval using a sceral suction trephine. RESULTS: The scleral suction trephine was cut evenly in our eyebank study. There was no additional trauma to the endothelium and the scleral rim was regular. CONCLUSION: Suction trephination of the sclera in retrieval of corneal donor tissue appears to be safe and effective.

Aged↗
PubMed1995

Supercritical fluid extraction of PCBs from human adipose tissue for HRGC/LRMS analysis.

Supercritical fluid extraction (SFE) of 36 PCBs from human adipose is presented. Selective extraction of the PCBs is achieved using supercritical CO2 with a density of 0.9 g/ml (281 bar) at 40 degrees C and with AlOx as a fat retainer. Compared to the traditional liquid extraction method followed by further sample clean up, SFE is not only faster (2 hours compared to three days) but also utilises lower amounts of organic solvents (4 ml compared to over 500 ml). The recoveries of 7 added 13C labelled PCBs are 83-106%. The repeatability in the analysis of 36 PCBs in 6 identical samples is excellent, with an average R.S.D. of less than 10%.

Adipose Tissue↗
PubMed1995

Absorption of polychlorinated biphenyls, dibenzo-p-dioxins and dibenzofurans by breast-fed infants.

The absorption of polychlorinated biphenyls, dibenzo-p-dioxins and dibenzofurans was studied in four breast-fed infants. The absorption was measured by comparing the estimated total intake and the excretion in faeces, during 48 hours, at three different time points; 1, 2 and 3 months post parta. The levels of the analysed compounds in the human milk are typical for Sweden, i.e approximately 20 ppt toxic equivalents for the dibenzo-p-dioxins and dibenzofurans and for the polychlorinated biphenyls approximately 16 ppt toxic equivalents. For most of the congeners the absorption is found to be over 95%. Higher excretion is noticed for heptachlorinated and octachlorinated dioxins.

Absorption↗
PubMed1995

Benefits of specular microscopy in evaluating eye donors aged 66 and older.

In the United States of America and worldwide, supplies of quality donor corneas continue to lag behind the demand. Some of what appears to be a shortage in the U.S.A. is really due to the custom of many surgeons to use only tissue from younger donors, thus creating an unnecessary waiting list. In reality, we do have a sizable pool of good donors in the older age group. With improved evaluation techniques, it is possible to identify these donors and to add their tissue to the supply of available corneas. This study shows that large numbers of corneas from donors over the age of 65 can be used successfully to restore vision. Specular microscopy provides valuable quantitative data to the surgeon, who ultimately makes the decision about the suitability of the donor tissue. For an eye bank, specular microscopy makes it easier to place older tissue, resulting in shorter waiting lists.

Aged↗
PubMed1992

Noninvasive measurement of diameter changes in the distal abdominal aorta in man.

An ultrasound phase-locked, echo-tracking system was used to determine the dynamic properties of the distal abdominal aorta in 10 Caucasian male subjects (mean age, 25 years). Recordings were made at rest and during the blood pressure increase resulting from isometric exercise. The pressure diameter curve was nonlinear with an inflection at about 90-110 mmHg. Above this pressure range, the vessel was stiffer (less compliant), but the pressure diameter relationship was roughly linear above as well as below the inflection. Individual pressure diameter curves showed hysteresis, i.e., the aorta had a smaller diameter during expansion than during retraction at corresponding pressures. The pressure strain elastic modulus (Ep) and stiffness (beta) were at rest [Mean Arterial Pressure (MAP), 81 mmHg] 0.70 10(5) N/m2 and 6.0, respectively. During isometric exercise (MAP, 122 mmHg), Ep increased significantly by 91% and stiffness (beta) nonsignificantly by 27%. The variability of the compliance determinations was 5% when the ultrasonic system was combined with intra-arterial blood pressure measurements and less than 7% when combined with auscultatory blood pressure measurements. It is concluded that the phase-locked, echo-tracking system fulfills clinical requirements for routine measurements of vascular compliance.

Adult↗