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T K Jensen

Publications and source records attributed to T K Jensen.

At least 73 records · Page 4Linked to original sources
PubMed1998

Specific detection of Lawsonia intracellularis in porcine proliferative enteropathy inferred from fluorescent rRNA in situ hybridization.

Fluorescent in situ hybridization targeting 16S ribosomal RNA was used for specific detection of the obligate intracellular bacterium Lawsonia intracellularis in enterocytes from pigs affected by proliferative enteropathy. A specific oligonucleotide probe was designed and the specificity of the probe was determined by simultaneous comparison with indirect immunofluorescence assay for detection of L. intracellularis in formalin-fixed tissue samples from 15 pigs affected by porcine proliferative enteropathy. We used 10 tissue samples from pigs without proliferative mucosal changes as negative controls. The results showed that the oligonucleotide probe is specific for L. intracellularis and that fluorescent in situ hybridization targeting ribosomal RNA is a suitable and fast method for specific detection and histological recognition of L. intracellularis in formalin-fixed tissue.

Animals↗
PubMed1998

Cryptorchidism and hypospadias in sons of gardeners and farmers.

Cryptorchidism and hypospadias have been related to prenatal estrogen exposure in animal models. Some chemicals used in farming and gardening have been shown to possess estrogenic and other hormone-disrupting effects. Earlier studies have indicated increased risks of urogenital malformations in the sons of pesticide appliers. In the present study, parental occupation in the farming and gardening industry among 6,177 cases of cryptorchidism, 1,345 cases of hypospadias, and 23,273 controls, born live from 1983 to 1992 in Denmark, was investigated in a register-based case-control study. A significantly increased risk of cryptorchidism but not hypospadias was found in sons of women working in gardening (adjusted odds ratio = 1.67; 95% confidence interval, 1.14-2.47). The risks were not increased in sons of men working in farming or gardening. The increased risk of cryptorchidism among sons of female gardeners could suggest an association with prenatal exposure to occupationally related chemicals.

Adolescent↗
PubMed1998

Association of Serpulina hyodysenteriae with the colonic mucosa in experimental swine dysentery studied by fluorescent in situ hybridization.

The localization of Serpulina hyodysenteriae in experimental swine dysentery was studied by fluorescent in situ hybridization (FISH) using an oligonucleotide probe targeting the 23S rRNA of S. hyodysenteriae. Nine 8-week-old pigs were challenged. Seven of the pigs were intragastrically dosed with 1 x 10(9) cfu S. hyodysenteriae for 3 consecutive days, whereas two pigs were infected by contact. Six non-challenged pigs served as negative controls. The challenged pigs developed clinical swine dysentery from 8 to 14 days postinfection with typical gross lesions. By FISH S. hyodysenteriae cells in huge numbers were found colonizing the mucus layer, the luminal epithelium and the crypts of the large intestinal mucosa. The orientation of the spirochaetes to the epithelium appeared to be random. Spirochaetes in clusters or as single cells were invading the epithelium and were occasionally detected in the adjacent lamina propria. The distribution of spirochaetes in the mucosa provides further evidence that S. hyodysenteriae is intimately associated with the mucus layer and the epithelium in a random pattern. Furthermore, the results demonstrate the applicability of FISH for specific detection of S. hyodysenteriae cells in clusters or as single cells in formalin-fixed tissue samples.

Animals↗
PubMed1997

Meat safety consequences of implementing visual postmortem meat inspection procedures in Danish slaughter pigs.

The consequences of a change from a traditional meat inspection procedure, including manual handling, palpation and incision, to an entirely visual postmortem meat inspection procedure in Danish slaughter pigs were assessed by a comparative study of the two methods in 183,383 slaughter pigs. Out of 58 lesion codes (selected with a prevalence > or = 5.5 x 10(-5)), 26 (45 per cent) were assessed either as merely aesthetic or as the healed stage of an earlier lesion and nine (15 per cent) as active, but local processes, occurring only in non-edible tissue. Five lesion codes (9 per cent) were assessed as active, non-abscessal processes occurring in edible tissue, caused by swine-specific pathogens and 10 (17 per cent) were abscessal or pyaemic lesions occurring in edible tissue. Seven lesion codes (12 per cent) may be associated with consumer health hazards (two frequently and five rarely), and one with occupational health hazards. It was estimated that per 1000 carcases, an additional 2.5 with abscessal or pyaemic lesions (in edible tissue) containing Staphylococcus aureus, 4 x 10(-4) containing ochratoxin, 0.2 with arthritis due to Erysipelothrix rhusiopathiae, 0.1 with caseous lymphadenitis, 0.7 faecally contaminated with Salmonella species, and 3.4 faecally contaminated with Yersinia enterocolitica would remain undetected as a result of changing from the traditional to the visual inspection procedure. Two valuable reasons for implementing a visual control system are the potential for decreased cross-contamination (no handling, cutting and incision) and reduced inspection costs. The resources released as a result may be reallocated to hygiene and surveillance programmes.

Abattoirs↗
PubMed1997

Specific detection of Serpulina hyodysenteriae and potentially pathogenic weakly beta-haemolytic porcine intestinal spirochetes by polymerase chain reaction targeting 23S rDNA.

A 2470-bp section of the 23S ribosomal DNA from Serpulina hyodysenteriae and five biochemically different groups of weakly beta-haemolytic porcine intestinal Serpulina strains was sequenced. The similarity between the sequenced strains was high (96.85% to 99.84%). A phylogenetic tree was estimated by the maximum likelihood method. The sequenced strains formed three groups. Serpulina hyodysenteriae and biochemical group II ('S. intermedius') formed a cluster, but 20 nucleotide positions were different between the two, suggesting that biochemical group II is a separate species. Another cluster consisted of the closely related biochemical group IIIa ('S. murdochii') and IIIb/c (S. innocens) (99.84% similarity), while biochemical group IV (S. pilosicoli) constituted a separate group with a relatively low similarity (96.85% to 97.01%) to the other groups. Three primer pairs were designed for specific PCR detection of the clinically important S. hyodysenteriae and biochemical group II and IV. PCR amplification was accomplished with DNA extracted from bacterial colonies by a simple boiling procedure, and with DNA extracted directly from porcine stool samples using a bead beating extraction procedure. The level of detection for the direct extraction and amplification method was 5 x 10(5) cells added g-1 normal faeces.

Animals↗
PubMed1997

Semen analysis performed by different laboratory teams: an intervariation study.

Some recent studies have indicated that sperm concentration has decreased during the last 50 years. However, comparisons between laboratories have revealed that geographical differences seem to exist and that any decrease may not be global. One point of criticism concerning comparison of results from different laboratories has been that some of the discrepancies detected could reflect the lack of standardized methods used in the different laboratories. Four teams, each consisting of one physician and one technician from groups which have recently published data on semen quality, met in order to evaluate the variability between their laboratories on semen analysis. Twenty-six fresh semen samples from unselected men were analysed. The groups analysed the samples according to the normal practice in their laboratories, using their own equipment. The variation between laboratories was estimated through a random effects model. For sperm concentration and semen volume assessment a remarkable consistency between laboratories was detected, in contrast to the very considerable inter-individual variation. For sperm motility and morphology assessments interlaboratory consistency was much poorer. In conclusion, evaluation of sperm motility and morphology characteristics requires further standardization in order to achieve comparable data from different laboratories. However, semen volume and sperm concentration are characteristics which can be compared reliably between laboratories, when similar methodologies are used.

Adolescent↗
PubMed1997

Microbiology and pathology of fibrinous pericarditis in Danish slaughter pigs.

The prevalence of fibrinous pericarditis detected at slaughter in Danish slaughter pigs is approximately 0.02%. The microbiology and pathology of this disorder was studied through 46 field cases collected at slaughter from May 1994 to August 1995. Mycoplasmas (Mycoplasma hyopneumoniae, M. hyosynoviae and M. hyorhinis) were isolated from the pericardium in 38 cases and from the joints in six. M. Hyopneumoniae dominated with 33 isolates from the pericardium. Actinobacillus pleuropneumoniae was isolated from the pericardium in three cases (as mono-infection in one and together with M. hyopneumoniae in two cases) and Actinomyces pyogenes was isolated from the pericardium twice (as mono-infection in one case and together with M. hyopneumoniae in another). A. pyogenes was also present in the lung, liver and kidney in one of these cases. Streptococcus suis was isolated together with mycoplasmas from the pericardium in three cases. The pericardium was sterile in three cases and contained a low grade mixed flora in two; the latter is believed to be a result of the slaughter procedure rather than an infection. No chlamydiae were found in connection with the microbiological examination. Parvovirus was found in one case in the pericardium and in two cases in the spleen. Forty-five cases were subacute to chronic. The gross pathological examination showed that bronchopneumonia, chronic pleuritis and synovitis or a low grade arthritis occurred in most cases. Only the arthritic lesions are believed to be pathogenetically concurrent with the pericarditis. Slight evidence of stasis of the liver and/or periangiolar edema was present in six cases. The histopathological examination confirmed the above mentioned findings. Bacterial colonies were found within the fibrinous layer on the pericardium in all cases from which either A. pleuropneumoniae, A. pyogenes or S. suis was isolated. It is concluded that in this study mycoplasmas, particularly M. Hyopneumoniae, are the more likely cause of fibrinous pericarditis in slaughter pigs.

Animals↗
PubMed1997

Inhibin B as a serum marker of spermatogenesis: correlation to differences in sperm concentration and follicle-stimulating hormone levels. A study of 349 Danish men.

Recent studies have focused on reproductive health of men in the general population. However, semen samples are difficult to obtain within sampling frames that allow comparisons. Blood samples are easier to obtain than ejaculates. Therefore, serum biomarkers of spermatogenesis are of major interest for population studies. FSH has previously been used as a marker of spermatogenesis, although it is also influenced by the hypothalamus. Serum inhibin B was recently suggested as a possible, more direct serum marker of spermatogenesis in men with testicular disorders. In a Danish nationwide collaborative study, we found an unexpected difference in semen concentration between two groups of men recruited from two different centres. We, therefore, analyzed reproductive hormones in blood, including inhibin B, to test whether the observed difference in semen concentration was reflected in the reproductive hormones. From 1992 to 1995, a total of 430 men, 20-35 yr old, who lived with a partner and who had not previously attempted to achieve a pregnancy, were recruited. The couples were enrolled into the study in one of two centres (centre A, n = 231; and centre B, n = 199) when they discontinued birth control. At enrollment, they provided a semen sample (n = 419), and a blood sample was drawn (n = 349). The semen analysis was performed in accordance with the WHO 1992 guidelines, and interlaboratory differences were tested. Inhibin B was measured in an enzyme immunometric assay, which has previously been described. All blood samples were analyzed in the same laboratory. Median sperm concentration and the percentage of morphologically normal spermatozoa were significantly higher among men from centre A (56.0 mill/mL and 42.5%), compared with men from centre B (44.8 mill/mL and 39%). Men from centre B had a significantly higher median FSH (3.42 IU/L) and a lower inhibin B (186 pg/mL) than men from centre A (3.21 IU/L and 209 pg/mL). The differences persisted after control for potentially confounding variables. A significant correlation was found between the cubic root-transformed serum FSH and inhibin B levels (r = -0.61, P < 0.001), between the cubic root-transformed serum FSH and sperm concentration (r = -0.40, P < 0.001), and between the cubic root-transformed inhibin B and sperm concentration (r = 0.38, P < 0.001). The predictive power of detecting sperm counts below 20 mill/mL among men who's inhibin B and FSH both were below 80 pg/mL and above 10 IU/L, respectively, was 100%. The unexpected significant difference in semen concentration between two groups of normal Danish men was probably caused by differences in sampling procedures in the two centres where the men were recruited, rather than geographical differences. However, similar differences in serum levels of inhibin B and FSH between centres were found. These findings suggest that a real difference in spermatogenic potential between the two groups of men existed. We suggest that serum inhibin B, in future population studies on male reproductive health, may serve as a new marker of spermatogenesis, in addition to sperm concentration and serum FSH.

Adult↗
PubMed1997

A discrete survival model with random effects: an application to time to pregnancy.

Time to pregnancy, the number of menstrual cycles it takes a couple to conceive, and various covariates have been collected among couples ultimately achieving conception. To assess the influence of the covariates, we constructed a discrete survival model that allows time-dependent covariates. A random effect was included to account for unobserved heterogeneity. The collected waiting times are obtained through retrospective ascertainment and are analyzed as truncated data. Maximum likelihood estimation was implemented by Fisher scoring through iteratively reweighted least squares.

Adult↗
PubMed1997

Dose related mucosal hyperplasia induced by Oesophagostomum dentatum infection in pigs.

The present work was undertaken to examine the effects of 3 different population densities of Oesophagostomum dentatum upon the development of worm induced mucosal changes in the colon following single infections. Groups of pigs were infected with single doses of 2000 (low dose), 20,000 (medium dose) or 200,000 (high dose) infective larvae, respectively. A total of 18 infected pigs (6 from each group) were examined for histopathological changes together with 3 helminth-free control pigs. There was a dose related difference in the intensity of colonic lesions; and using morphometry it was observed that the mucosal crypts of pigs in the high dose group were significantly longer than those in the 2 other groups. These differences disappeared by day 25 after infection despite the presence of larvae in the mucosa of the high dose group. This phenomenon may be related to inflammatory reactions in the colon, possibly in connection with the initiation of an immunological response in sites distant from the parasite larvae.

Animals↗
PubMed1996

Male reproductive health and environmental xenoestrogens.

Male reproductive health has deteriorated in many countries during the last few decades. In the 1990s, declining semen quality has been reported from Belgium, Denmark, France, and Great Britain. The incidence of testicular cancer has increased during the same time incidences of hypospadias and cryptorchidism also appear to be increasing. Similar reproductive problems occur in many wildlife species. There are marked geographic differences in the prevalence of male reproductive disorders. While the reasons for these differences are currently unknown, both clinical and laboratory research suggest that the adverse changes may be inter-related and have a common origin in fetal life or childhood. Exposure of the male fetus to supranormal levels of estrogens, such as diethlylstilbestrol, can result in the above-mentioned reproductive defects. The growing number of reports demonstrating that common environmental contaminants and natural factors possess estrogenic activity presents the working hypothesis that the adverse trends in male reproductive health may be, at least in part, associated with exposure to estrogenic or other hormonally active (e.g., antiandrogenic) environmental chemicals during fetal and childhood development. An extensive research program is needed to understand the extent of the problem, its underlying etiology, and the development of a strategy for prevention and intervention.

Animals↗
PubMed1995

Do environmental estrogens contribute to the decline in male reproductive health?

Several observations suggest that male reproductive health has been declining since World War II in many countries. The incidence of testicular cancer, hypospadias, and cryptorchidism has been increasing and semen quality has been decreasing, and these may have a common etiology. Treatment of several million pregnant women with the synthetic estrogen diethylstilbestrol led to an increase in these conditions among the sons of these women. These abnormalities probably arise during fetal development. The similarity between these effects and the adverse change in male reproductive development and function raised the question of whether the adverse changes are attributable to altered exposures to estrogenic and other endocrine-disrupting agents during fetal development. We speculate that alteration in exposure to estrogen in the past half-century may have caused the changes in male reproductive health.

Cryptorchidism↗
PubMed1992

[Cigarette smoking and time before pregnancy among Danish pharmacy assistants].

The relationship between time to pregnancy and cigarette smoking was studied in a group of 4,924 pharmacy assistants under 40. The information was collected by means of a self administered questionnaire and the response rate was 92%. The data were analysed by a recently developed statistical model for description of time to pregnancy, which provides a more revealing test than the classic contingency table analysis. The study shows that smokers have a median time to pregnancy which is 27% longer than for non smokers. This may partly be due to lifestyle associated with smoking (e.g. alcohol and caffeine intake). Lifestyles such as these have been reported to prolong time to pregnancy. It is shown that time to pregnancy is an easily obtained measurement of fecundity. Only 3.6% of the women were unable to remember their time to pregnancy. The conclusion of the study was that information pertaining to the relationship between fertility and smoking habits/lifestyle should be a part of the instruction for women who wish to become pregnant.

Adult↗
PubMed1991

Procedure-related rate of contact of intensive care unit personnel with patient body fluids.

We prospectively recorded the frequency with which ICU personnel came in contact with body fluids in order to provide an empirical basis for the recommendation of relevant protective precautions. ICU personnel completed a questionnaire when performing a range of 29 standardized procedures. The rate of contact with body fluid was: manual ventilation (55%); catheterization of peripheral vein (36%); insertion of central venous catheter (69%); arterial puncture (18%); tracheal intubation (76%); tracheal extubation (87%); suction from mouth, pharynx or trachea (82%); drawing of blood sample (52%); establishing or discontinuing blood transfusion (50%); establishing or discontinuing infusion (20%); changing of wound dressing (52%). We suggest that the contact rates observed should be used in combination with a universal precautions policy, in order to identify procedures that are likely to involve contact with body fluid. By using gloves 95% of contacts to body fluid would have been prevented.

Body Fluids↗
PubMed1991

Hemodynamics and arterial oxygen saturation during preoperative emptying of the stomach.

We studied the hemodynamic response to preoperative emptying of the stomach by means of a gastric tube in 20 non-fasting non-premedicated patients aged 39 (24-54) (median and quartiles) presenting for emergency surgery. Systolic and diastolic blood pressure and heart rate increased by 24.4% (P less than 0.01), 29.9% (P less than 0.01) and 36% (P less than 0.01), respectively. Arterial oxygen saturation decreased by 2.1% (P less than 0.01). The rate pressure product increased by 68% (P less than 0.01), exceeding 20,000 (mmHg.min-1) [2667 kPa.min-1] in nine patients. The cardiovascular response is of the same magnitude as reported after tracheal intubation without use of analgesics and is likely to cause cardiac ischemia and other adverse effects in patients suffering from coronary artery disease.

Adult↗
PubMed1990

Relationship between anesthetic procedure and contact of anesthesia personnel with patient body fluids.

We recorded the frequency with which anesthesia personnel came in contact with patient body fluids in order to provide an empirical basis for the recommendation of relevant precautions. Anesthesia personnel completed a questionnaire when performing a range of standardized procedures. The rate of contact with blood was as follows: catheterization of peripheral vein, 18%; insertion of central venous catheter, 87%; arterial puncture, 38%; lumbar puncture, 23%; catheterization of the extradural space, 34%; tracheal intubation, 4%; tracheal extubation, 9%; suction of oral cavity, pharynx, or trachea, 13%; intramuscular injection of drug, 8%; and establishment or discontinuation of drip for blood transfusion, 43%. By using protective gloves, 98% of contacts with patient blood would have been prevented. Blood contact was more frequent in the emergency ward than in the operating room (P less than 0.05). Health care workers were not able to predict when a specific procedure would imply that contact with patient blood would occur. We recommend that specific precautions be adopted for the various procedures and discuss precautions that could have prevented contact with body fluid.

Anesthesiology↗