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Biomedical subjects

D Heim

Publications and source records attributed to D Heim.

At least 37 records · Page 2Linked to original sources
PubMed2001

Targeted screening of high-risk cattle populations for BSE to augment mandatory reporting of clinical suspects.

In Switzerland, the first case of bovine spongiform encephalopathy (BSE) was diagnosed in November 1990. Case numbers peaked in 1995, with a total of 352 BSE cases identified by 30 April 2000. Reporting of clinically suspect cattle is currently the most commonly used method world-wide to detect BSE cases. The effectiveness of mandatory reporting depends on a variety of factors; for other diseases passive surveillance underestimates the incidence of clinical cases. The efficiency of passive surveillance systems for BSE will remain unknown until screening tests able to identify clinically affected cattle have been applied in several countries. This paper provides the first detailed description of a targeted screening programme for BSE. Two populations of cows >24 months of age were included in the targeted screening: (i) cows found dead or culled on site where the carcass was submitted to rendering (fallen stock) and (ii) cows with health-related problems unfit for routine slaughter that were slaughtered under emergency procedures (emergency slaughter). Between 1992 and 1999, on average 81 clinical BSE suspects per year were reported to the veterinary authorities (passive surveillance), of which 43% were confirmed with BSE. A total of 30 clinical cases were captured by passive surveillance and an additional 20 BSE cases detected by targeted screening between May 1999 and April 2000. The odds of finding a BSE case was 49 times higher in the fallen stock and 58 times higher in emergency-slaughtered cattle when compared to passive surveillance. The targeted screening of fallen stock and emergency-slaughtered cattle considerably increased the number of detected cases in this 12-month period. Targeted-screening cases were on average 4 months younger than the clinical suspect cases. In conclusion, post-mortem testing of fallen stock and emergency-slaughtered cows >24 months for BSE is an important active surveillance element within a total surveillance system that principally is based on mandatory reporting of clinical suspect cases. Without ante-mortem screening tests to detect BSE-infected cattle during the incubation period, a combination of effectively functioning passive and active BSE surveillance strategies might be the only approach to assess the BSE situation reliably in a given country or region - and it is necessary to substantiate claims of freedom from the disease.

Animals↗
PubMed2001

[Occurrence of scrapie in Switzerland: an anonymous cross-sectional study].

Scrapie is a transmissible spongiform encephalopathy of sheep and goats, which leads to neurological signs and ends with the death of the infected animal. In Switzerland only a few cases were reported since 1982. In 1999, a questionnaire survey was conducted to increase information about neurological diseases in sheep and goat breeding farms. The aim was to estimate the frequency of neurological disorders including Scrapie and to increase the disease awareness of sheep and goat breeders. The main goal of the study was to increase the reporting of suspect cases of Scrapie and its differential diagnoses. Out of a database of all registered farms with at least five breeding sheep or breeding goats a random sample of 4711 was drawn to which anonymous questionnaires were sent. The return rate was 36%. In a parallel study, 150 voluntarily participants were interviewed using the same questionnaire. The results of both parts of the survey coincided. For the years 1997 and 1998, on average 1.0% of the breeding sheep and breeding goats showed neurological signs. 7.7% of the breeders indicated to have observed animals with neurological symptoms in their flock. At the population level, a total of 1954-2336 animals with neurological signs are observed in 691-929 flocks. The minority is reported to the veterinary authorities.

Animals↗
PubMed2000

Surveillance of BSE.

The current method used to identify suspect BSE cases is based on reporting cattle displaying clinical signs compatible with BSE. The reporting of such cases is dependent on the ability of farmers and veterinarians to recognise the disease symptoms and on the willingness to report such cases. Furthermore, it depends on the stage of the disease, because early clinical signs of BSE are not always typical. Histology and immunohistochemistry are established and reliable to confirm BSE in cattle, but the procedure is cumbersome, time consuming and therefore not suited for mass testing of animals. A targeted surveillance system using the Prionics-Western-Blot Test was initiated in Switzerland in 1999. Prionics-positive results are confirmed by histology or immunohistochemistry by the BSE-reference laboratory. This surveillance scheme has confirmed fallen stock and cows subjected to emergency slaughter as the major risk groups. Currently all cattle from these two categories are tested. As a further measure a random sample of cows from regular slaughtering is tested. This enables to determine the BSE status independent of the inaccuracies of a clinical case reporting system. This approach may be helpful to reliably assess the BSE situation in countries with low incidence in order to verify their BSE status and in countries which want to prove their BSE-free status.

Animals↗
PubMed2000

Application of Prionics Western blotting procedure to screen for BSE in cattle regularly slaughtered at Swiss abattoirs.

Disease-specific PrP (PrP(Sc)) is at least part of the infectious particle (prion) causing bovine spongiform encephalopathy (BSE) or scrapie in sheep. Digestion with protease allows a distinction between normal PrP (PrP(C)) and PrP(Sc) i.e. PrP(C) is completely digested while PrP(Sc) is cleaved at the N-terminus leading to a fragment of reduced molecular weight (PrP 27-30). Detection of this fragment by Western blotting has been described more than a decade ago for rodent PrP. We have now optimized the technique in order to allow rapid analysis of hundreds of samples per day. Here we report the application of this technique to the analysis of 3000 regularly slaughtered cattle from Swiss abattoirs. For comparison all the animals were subsequently examined by classical methods (i.e. histology and immunohistochemistry). All but one animal were negative for BSE by all methods. The Western blot positive animal was confirmed to be a BSE case and the carcass was removed from the food chain. We conclude that it is feasible to examine slaughtered cattle on a routine basis without causing delays to the meat processing industry.

Abattoirs↗
PubMed2000

[Plate osteosynthesis of distal radius fractures--incidence, indications and results].

UNLABELLED: From 1.1.95 to 31.12.98 133 distal radius fractures were treated surgically. Internal fixation with a plate was carried out in 34 fractures (25%). 17 plates were placed dorsally, 16 plates on the volar aspect and one fracture was treated with a combined dorsal and volar plate. 29/34 fractures (87%) were reviewed 1 year after surgery. All fractures healed without further surgery. No infection occurred. 15 implants were removed. 23/29 (79%) internal fixations showed a good or excellent result, 6/29 (21%) a fair result. These 6 patients had in common: an intraarticular fracture (5), a volar tilt (5), a postoperative algodystrophy (5) or a secondary dorsal displacement (2). IN CONCLUSION: One fourth of all surgically treated distal radius fractures underwent plate osteosynthesis with about 80% of good or excellent results. Dorsal plate osteosynthesis showed better results than volar plate fixation. An additional, temporary external fixator in fractures with radial shortening proved a reliable help intraoperatively. Secondary displacement in these fractures did not occur.

Adolescent↗
PubMed2000

[Ten years of BSE in Switzerland. The development of an extraordinary disease].

The first case of bovine spongiform encephalopathy (BSE) in Switzerland was diagnosed in November 1990. BSE is--in particular considering its eradication--different from many other livestock diseases. Strict disease control measures were taken from the very beginning by the Swiss authorities in order to protect public as well as animal health. In addition, BSE has stimulated enormous media interest and public concern. The occurrence of the born after the ban (BAB) cases, increasing questions about the zoonotic potential of the disease and trade restrictions against Switzerland led to the "BSE-crisis". In 1999, Switzerland internationally took a leading role in the surveillance of BSE by active investigation of targeted risk population.

Animals↗
PubMed1999

In vivo marking of rhesus monkey lymphocytes by adeno-associated viral vectors: direct comparison with retroviral vectors.

We have compared adeno-associated virus (AAV)-based and retrovirus-based vectors for their ability to transduce primary T lymphocytes in vitro and then tracked the persistence of these genetically marked lymphocytes in vivo, using the rhesus monkey model. To avoid the complication of immune rejection of lymphocytes transduced with xenogeneic genes in tracking studies primarily designed to investigate transduction efficiency and in vivo kinetics, the vectors were designed without expressed genes. All vectors contained identically mutated beta-galactosidase gene (beta-gal) and neomycin resistance gene (neo) DNA sequences separated by different length polylinkers, allowing simple differentiation by polymerase chain reaction (PCR). Each of 2 aliquots of peripheral blood lymphocytes from 4 rhesus monkeys were transduced with either AAV or retroviral vectors. The in vitro transduction efficiency (mean vector copy number/cell) after the ex vivo culture was estimated by PCR at 0.015 to 3.0 for AAV, varying depending on the multiplicity of infection (MOI) used for transduction, and 0.13 to 0.19 for the retroviral transductions. Seven days after transduction, Southern blot analysis of AAV-transduced lymphocytes showed double-stranded and head-to-tail concatemer forms but failed to show integration of the AAV vector. AAV and retroviral aliquots were reinfused concurrently into each animal. Although the retrovirally marked lymphocytes could be detected for much longer after infusion, AAV transduction resulted in higher short-term in vivo marking efficiency compared with retroviral vectors, suggesting possible clinical applications of AAV vectors in lymphocyte gene therapy when long-term vector persistence is not required or desired.

Animals↗
PubMed1999

Modelling the expected numbers of preclinical and clinical cases of bovine spongiform encephalopathy in Switzerland.

The objective of this study was to model the expected numbers of cattle incubating bovine spongiform encephalopathy (BSE) and the numbers of clinical cases of BSE in the Swiss cattle population between 1984 and 2005. The results were compared with the observed number of clinical BSE cases and with the results of a culling and testing scheme on herdmates of cattle with BSE. The age distribution of the Swiss cattle population, the age-at-death distribution of the first 235 BSE cases and exposure information were used to calculate the expected number of infected cattle in each birth cohort and the resulting numbers of clinical cases and survivors incubating the disease for each year. The model which did not assume any under-reporting of cases fitted the observed epidemic curve of clinical cases reasonably well, and predicted that the Swiss BSE epidemic would come to an end between 2003 and 2005. The age of survivors incubating BSE is increasing. The higher than expected incidence of subclinical cases observed in animals from the culling scheme is most probably the result of the heterogeneous distribution of infected animals and affected herds in the population. The results of the model need to be taken into account when designing surveillance and testing schemes for BSE.

Age Distribution↗
PubMed1999

Validation of a western immunoblotting procedure for bovine PrP(Sc) detection and its use as a rapid surveillance method for the diagnosis of bovine spongiform encephalopathy (BSE).

In this report we document the results of several independent studies testing the sensitivity, specificity and reliability of the Prionics Western blotting (PWB) procedure to detect bovine and ovine disease-specific, protease-resistant prion protein (PrP(Sc)). Validation of the technique was obtained by blind analysis of samples from cattle affected with bovine spongiform encephalopathy (BSE), clinically normal animals or cattle with neurological diseases unrelated to BSE. Overall, very high sensitivity, specificity and reliability was observed. It became clear that sampling of the correct brain region and the method used for protein extraction are important factors for correct diagnosis. Furthermore, we tested the usefulness of the PWB technique as an instrument for surveillance purposes. We analyzed animals from a culling scheme as well as older animals from abattoirs to determine the number of subclinical BSE cases detectable by histopathological examination, immunohistochemistry for PrP(Sc) and PWB. In both studies, BSE-affected animals with no overt clinical symptoms were detected. These results demonstrate the usefulness of the PWB procedure in surveillance systems serving as a rapid diagnostic tool to identify animals subclinically infected with BSE.

Animals↗
PubMed1999

[Quality assurance: the AO documentation at a peripheral hospital].

Follow-up of fracture treatment one year after surgery based on AO Documentation in a small, rural hospital in a region with many tourists is demanding. How many patients can be contacted and assessed at the one year follow-up? From 1.1.95 to 31.12.96 302 patients with 314 fractures were operated on and the results subsequently documented. 255 patients (84%) were assessed personally (221) or by an AO member or family doctor (34). 15 patients died before the appointment, 32 patients could not be contacted or their data was incomplete. To achieve this rate of follow-up, some internal organization in the hospital was necessary, as will be described in this paper. AO Documentation is an important tool for personal quality assurance, especially in small hospitals. Small hospitals might be interesting for the AO since their follow-up rate can be high due to a simple organization and a personal patient-doctor relationship.

Aged↗
PubMed1999

Bovine spongiform encephalopathy in Switzerland--the past and the present.

The first case of bovine spongiform encephalopathy (BSE) in Switzerland was diagnosed in November 1990, although the risk factors identified in the United Kingdom were not all present in Switzerland. At 29 December 1998, a total of 282 BSE cases (all animals born in Switzerland), had been recorded. The number of cases is declining, with fourteen cases diagnosed in 1998 (at 29 December 1998). The measures taken are effective. However, the potential weakness in current activities that allow the disease to exist are being evaluated. Further measures to avoid even minimal risk for human and animal health will be taken if required. Experience gained from the past indicates that it is necessary to review the situation constantly and to inform the public and professionals regularly and in a transparent manner.

Animals↗
PubMed1999

The skier's thumb.

The incidence of skier's thumb (rupture of the ulnar collateral ligament of the first metacarpophalangeal joint) is increasing. To determine whether conservative or surgical treatment is indicated, ultrasound (US) and magnetic resonance imaging (MRI) have been advocated in the last few years. Surgery should be performed in the case of an unstable joint with a ligamentous tear or in the presence of a displaced bony fragment. Several techniques for surgical repair in acute and old ruptures are proposed. Conservative and postoperative treatment consists of immobilization of the joint in a splint or thumb spica cast for 4 weeks. The best results are obtained in bony avulsion fractures. Conservative treatment of lesions requiring surgical treatment may result in permanent disability of the joint; thus, correct diagnosis is mandatory.

Casts, Surgical↗
PubMed1999

Effects of acarbose treatment in Type 2 diabetic patients under dietary training: a multicentre, double-blind, placebo-controlled, 2-year study.

This 24-months, placebo-controlled, double-blind, randomised, group comparison study investigated the effect of acarbose vs placebo for improving metabolic control in patients with Type 2 diabetes under dietary training insufficiently controlled by diet alone. Patients randomised to acarbose had their dose increased in a stepwise manner to week 5. From week 5 onwards, they received 100 mg three times daily. This incremental dosing scheme was matched in the placebo group. All patients received specialist, intensive, continuous dietary training and counselling throughout the 2 yr of the study. Of the 74 patients randomised, 60 were included in the per-protocol analysis (28 receiving acarbose; 32 receiving placebo). HbA1c was the primary target variable. Per-protocol analysis found that, after 24 months, the mean difference in HbA1c relative to baseline value was -1.71+/-1.6% in the acarbose group and -0.82+/-1.1% in the placebo group. End-point values were 6.85+/-1.7% in the acarbose group and 7.41+/-1.1% in the placebo group. This difference between acarbose and placebo was statistically significant (p=0.02). Patients were defined as responders if they did not require additional treatment with an antidiabetic agent during the study. The responder rate under acarbose therapy was 89%, compared with 47% for placebo (p=0.0005). Acarbose-treated responders improved their HbA1c level to 6.45+/-0.82% after 24 months. The efficacy of acarbose was consistent throughout the study; decreasing efficacy was not evident. The results demonstrate the efficacy of acarbose for improving metabolic control in patients with Type 2 diabetes, even when such patients receive good dietary treatment and counselling.

Acarbose↗
PubMed1998

Quantitative immunophenotypic characterization, cryopreservation, and enrichment of second- and third-trimester human fetal cord blood hematopoietic stem cells (progenitor cells).

OBJECTIVE: The aims of this study were (1) to assess the hematopoietic stem cell (progenitor cell) contents of umbilical cord blood samples from second-trimester and early-third-trimester fetuses versus term fetuses and (2) to determine the feasibility of cryopreservation and enrichment of cord blood from fetuses of different gestational ages. STUDY DESIGN: Cord blood between 13 and 42 weeks' gestation (n = 31) was sampled after delivery or fetal expulsion. Fluorescence-activated cell sorting was used to measure CD34(+) and CD34(+)CD38(-) cell numbers. Samples were cryopreserved with 10% dimethylsulfoxide, and CD34(+) enrichment was performed by magnetically activated cell sorting with the MiniMACS system (Miltenyi Biotech, Bergisch Gladbach, Germany). Kruskal-Wallis analysis of variance and the Mann-Whitney U test were used for analysis of data. RESULTS: CD34(+) and CD34(+)CD38(-) cell contents were significantly higher in second- and early third-trimester fetuses than in term fetuses (CD34(+) 2.57% +/- 0.38%, 1.48% +/- 0. 31%, and 0.7% +/- 0.13%, respectively, P =.0067; CD34(+)CD38(-) 0. 72% +/- 0.26%, 0.18% +/- 0.05%, and 0.06% +/- 0.02%, respectively, P =.0132). Mononuclear cell recovery, viability, and CD34(+) cell purity after cryopreservation and enrichment were similar among different gestational ages. CONCLUSION: Cord blood stem cell content decreases significantly from the second trimester to term. Cryopreservation and enrichment of these cells from earlier gestational ages is feasible. This might be especially useful for allogeneic stem cell transplantation and for in utero gene therapy.

ADP-ribosyl Cyclase↗
PubMed1998

[182 offspring of cows with bovine spongiform encephalopathy (BSE) in Switzerland. 2. Epidemiology and pathological findings].

In order to detect lesions of a spongiform encephalopathy and/or accumulation of the protease resistant prion protein (PrPres), 182 offspring of cows affected with BSE were examined neuropathological and immunohistochemically. Neither spongiform encephalopathy nor PrPres accumulation were found. In seven animals other neuropathological lesions were seen, significant ones in three. Because of the small risk of exposure to contaminated feed in these animals, nearly all of which were born after the introduction of the protein feed ban for ruminants, the occurrence of spongiform encephalopathy in this series of BSE offspring would be suggestive of maternal transmission. However, the value of the study in this respect is quite limited. Only half of the animals were old enough to develop clinical and pathological evidence of the disease. If a maternal effect on the risk for the offspring is only to be expected during the last 6 months of the incubation of the dam as suggested by British investigations, only few animals in this study would fulfil the requirement of having been born during this critical period. Since it cannot be entirely excluded that the BSE agent transiently invades extraneural tissues in the early stages of infection, the above mentioned restriction to the final 6 months of the incubation time of the dam would not necessarily be applicable to all situations. We concluded that this study supports previous observations according to which maternal transmission of BSE is at best a rare event.

Animals↗
PubMed1997

[Frequency of neurologic diseases in cattle].

The cases of neurological diseases at the Institute of Animal Neurology, University of Berne, from 1985-1994 were assessed. During this period 532 cattle with neurological symptoms were examined. After 1980 differential diagnostic investigation of rabies negative brains were not pursued anymore and the number of examined cattle brains had declined to 25-30 per year. With the occurrence of bovine spongiform encephalopathy (BSE) in 1990 in Switzerland the number of cattle brains examined has increased to 75-80 yearly. The most frequently diagnosed neurological diseases found are BSE, followed by listeriosis and viral encephalitides.

Animals↗