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Biomedical subjects

J Hau

Publications and source records attributed to J Hau.

At least 19 recordsLinked to original sources
PubMed2004

Implementation of the 'three Rs' in biomedical research.

A systematic sample of 2800 articles published between 1970 and 2000 in 14 major biomedical journals was analysed to assess the implementation of the 'Three Rs' (replacement, reduction and refinement) in biomedical research. During this period the total number of articles published annually by the journals more than doubled, but the proportion of studies using animals decreased by 30 per cent. There was a significant increase, from 21 per cent to 35 per cent, in the proportion of animal studies which made use of untreated euthanased animals as donors of biological materials, a gradual decrease in the number of chronic studies on animals, and a 50 per cent decrease in the average number of animals used per published paper. There was an improvement in the reporting of the specification of the animals' husbandry, conditions of care and environment. Parameters of importance for the evaluation of the scientific quality of the research and the welfare of the animals were generally poorly reported, but the proportion of papers with adequate information on most of the parameters analysed increased between 1970 and 2000.

Animal Husbandry↗
PubMed2004

Surveys on attitudes towards legalisation of euthanasia: importance of question phrasing.

AIM: To explore whether the phrasing of the questions and the response alternatives would influence the answers to questions about legalisation of euthanasia. METHODS: Results were compared from two different surveys in populations with similar characteristics. The alternatives "positive", "negative", and "don't know" (first questionnaire) were replaced with an explanatory text, "no legal sanction", four types of legal sanctions, and no possibility to answer "don't know" (second questionnaire). Four undergraduate student groups (engineering, law, medicine, and nursing) answered. RESULTS: In the first questionnaire (n = 684) 43% accepted euthanasia (range 28-50%), 14% (8-33%) did not, and 43% (39-59%) answered "don't know". Two per cent of the respondents declined to answer. In comparison with previous surveys on attitudes to euthanasia the proportion of "don't know" was large. The results of the second questionnaire (n = 639), showed that 38% favoured "no legal prosecution" (26-50%). However, 62% (50-74%) opted for different kinds of legal sanctions, and two of four groups expressed significantly different views in the two surveys. A proportion of 10% declined to answer the second questionnaire. CONCLUSION: An introduction of an explanatory text and a wider range of response alternatives produced differences between the results of the two surveys conducted.

Attitude of Health Personnel↗
PubMed2004

Impact of chronic catheterization and automated blood sampling (Accusampler) on serum corticosterone and fecal immunoreactive corticosterone metabolites and immunoglobulin A in male rats.

Jugular catheters were inserted in nine male rats under general isofluorane anesthesia and the catheters were connected to a commercially available computerized blood sampling device (Accusampler). Blood samples (150 microl) were collected every 4 h during the first 24 h after surgery and every 12 h during the following 72 h until 94 h after surgery, when the animals were killed. All fecal pellets were collected at blood sampling. Serum corticosterone and fecal concentrations of immunoreactive corticosterone metabolites and immunoglobulin A (IgA) were quantified by ELISAs. In blood, high corticosterone concentrations (>200 ng/ml) were recorded in the first samples obtained after surgery, but the concentrations decreased steadily during the day and became cyclical, showing a diurnal variation with high levels during evenings and low levels in the mornings. The automatic blood sampling itself did not result in recordable increases in serum corticosterone concentrations. The time delay between the presence of elevated corticosterone levels in blood and in feces was approximately 12 h. Fecal immunoreactive corticosterone metabolite levels remained elevated during the 94 h study period after surgery. The fecal concentrations of IgA showed substantial between-animal variation and decreased non-significantly after the surgery. Like serum corticosterone, fecal IgA showed a diurnal variation in amounts excreted, in this case with high values in the morning and low values in the evening. The concentrations of fecal corticosterone and IgA were negatively correlated in samples obtained before surgery but no correlation existed after surgery. This indicates that fecal immunoreactive corticosterone metabolites, but not IgA, constitute a good marker of acute stress. For immunoreactive corticosterone metabolites as well as for IgA, the concentration in feces correlated well with total excretion, making single fecal samplings usable as a measure of total secretion.

Acute Disease↗
PubMed2001

Characterisation of modified whey protein in milk ingredients by liquid chromatography coupled to electrospray ionisation mass spectrometry.

Whey proteins are an important ingredient in the food industry. We have investigated the protein composition of commercial whey samples by liquid chromatography coupled to electrospray ionisation mass spectrometry on a time-of-flight instrument. We found that industrial whey protein contains a multitude of different modifications, ranging from almost native proteins through different degrees of glycosylation and oxidation up to almost completely oxidised forms. The information obtained allows characterisation of the influence of industrial processing on protein modifications and classification of whey protein-based ingredients or milk powders from different suppliers.

Animals↗
PubMed2001

Tandem mass spectrometric accurate mass performance of time-of-flight and Fourier transform ion cyclotron resonance mass spectrometry: a case study with pyridine derivatives.

The interpretation of mass spectra is a key process during compound identification, and the combination of tandem mass spectrometry (MS/MS) with high-accuracy mass measurements may deliver crucial information on the identity of a compound. Obtaining accurate mass data of fragment ions in MS/MS reveals the particular problem of mass calibration when a lockmass, which is frequently used to obtain accurate masses in MS, is absent. An alternative technique is to recalibrate the MS/MS spectrum using a reference MS/MS spectrum acquired under the same conditions. We have tested and validated this approach using a hybrid quadrupole/orthogonal acceleration reflectron-type time-of-flight (TOF) mass spectrometer. The results were compared with those obtained under similar conditions on a Fourier transform ion cyclotron resonance (FT-ICR) instrument. We found that the mass accuracy observed with such an "external" recalibration on the TOF instrument in MS/MS is identical to what can be obtained on a similar instrument operating in one-dimensional MS mode using the lockmass technique. However, mass accuracy in both cases is one order of magnitude inferior to that obtained using FTMS, and also inferior to that observed using sector field MS when operated at comparable resolution. Nevertheless, for small (<200 Da) molecules, this mass accuracy was still sufficient to have the "true" elemental composition identified as the first hit in about 70% of all cases. It was possible to elucidate the fragmentation mechanism of eight azaheterocycles containing a pyridine moiety, where the accurate mass data from the TOF instrument allowed distinction between two alternative fragmentation pathways.

Cyclotrons↗
PubMed2001

Improved method to track chlorophyll degradation.

An analytical method capable of identifying >30 chlorophyll-related compounds in plant extracts has been developed. The method employs liquid chromatography coupled to UV-vis, MS, and MS/MS detection. It can be applied without modification to analyze natural chlorophyll degradation products and other metalloporphyrines. It was successfully applied to identify chlorophyll derivatives found in rehydrated spinach powder and conventionally canned and Veri-Green-processed beans. In the Veri-Green-processed beans several degradation products were identified that are zinc-containing analogues to the chlorophyll derivatives found in vegetables after conventional canning. They have been characterized by liquid chromatography and mass spectrometry.

Chlorophyll↗
PubMed2001

Religious beliefs and opinions on clinical xenotransplantation--a survey of university students from Kenya, Sweden and Texas.

This study investigated the association between religious beliefs and opinions on xenotransplantation among students from three different countries. A lower proportion of religious students accepted xenotransplantation than did non-religious students. A higher proportion of Protestant students seemed to accept xenotransplantation than did Muslim and Roman Catholic students. A higher proportion of the religious respondents had not formed an opinion on xenotransplantation compared to non-religious students. There was no difference according to gender on views on xenotransplantation, but a higher proportion of older students seemed to accept xenotransplantation than did younger students. A higher proportion of non-vegetarians reported acceptance of xenotransplantation than did vegetarians. Acceptance of xenotransplantation was higher in Sweden compared to the two other regions, and the proportion of students who had formed an opinion was higher as well.

Adult↗
PubMed2001

Practical approach to archival and retrieval of analytical data in the laboratory.

Today's analytical laboratory uses a large number of different instruments that are connected in networks. Together with increasing automation, data are produced at a rate that can easily reach gigabytes per month, which generates the problem of systematic archival. In addition, working under Good Laboratory Practice requires that archival of raw data be performed in such a way that they can be readily retrieved upon request, even years later. While systematic archival of data is already performed in most laboratories, it is the retrieval of saved information that is often far from straightforward. This paper describes a simple but systematic approach for both archival and retrieval of data files and related electronic documents. It consists of an unambiguous scheme for the naming of electronic files, an efficient backup strategy, a simple database holding information about any data acquired, and a convenient interface to this database that can be accessed from any workplace while assuring restricted access. The system is capable of handling several databases concurrently and is used in our facility to archive data from several workgroups. The use of freely available software such as the Linux operating system made it possible to implement a fast and stable solution at exceptionally low cost.

Chemistry Techniques, Analytical↗
PubMed2001

Undergraduate and postgraduate students' responses to mandatory courses (FELASA category C) in laboratory animal science.

The results from the analysis of the course evaluations from FELASA category C compulsory courses in laboratory animal science at Uppsala University showed that the students realize that theoretical knowledge of the subject and practical skills are of great importance to the success of their future research involving animal experiments. All the subjects and elements of the course, in particular the practicals on animal handling and procedures using live anaesthetized animals, were fully appreciated by the students.

Adult↗
PubMed2001

An overview of animal models in experimental schistosomiasis and refinements in the use of non-human primates.

The complex nature of the schistosome parasite and its interaction with the mammalian host necessitates the continued use of live intact animal models in schistosomiasis research. This review acknowledges this necessity and highlights some of the important insights into the pathogenesis of the disease that have been gained from using various animal models. The use of non-human primates as more relevant models of human schistosomiasis is stated. In addition, the importance of animal welfare consideration when using primates for research is emphasized. Finally, some guidelines for the refined capture, handling and early humane endpoints for non-human primates to be used in experimental schistosomiasis are suggested.

Animal Welfare↗
PubMed2001

Development and validation of a sensitive ELISA for quantification of secretory IgA in rat saliva and faeces.

Non-invasive measures of immunological markers are an attractive means of stress assessment in laboratory animals. Salivary IgA has been used successfully as a stress marker in the human, and several reports indicate the potential of secretory IgA as a non-invasive measure of stress in animals. The present paper describes the development of an ELISA using commercially available components for the quantification of rat IgA and validation of this assay for the quantification of rat secretory IgA in saliva and faeces. The concentration of IgA in rat saliva varied significantly between duplicate samples obtained from individual rats, and the viscosity and small total volume of rat saliva gave unsatisfactory results for IgA. Faecal IgA was present in high concentrations, and duplicate samples varied by only 2-3%. However, faecal IgA seemed less stable than IgA in other biological compartments, and this finding must be taken into consideration when using quantitative measurements of IgA as a marker of mucous humoral immune status.

Animals↗
PubMed2000

Complement activation in SCID and nude mice is related to severity of tissue inflammation in the Candida mastitis model.

A small animal model of localised candidiasis is needed for the evaluation of new antifungal compounds. Mammary glands of immunocompetent (BALB/cJ) and immunodeficient (SCID and athymic nude) mice were infected with a wild-type of Candida albicans. Some of the animals were treated with amphotericin B (AmB) while others were treated with saline and acted as controls. The histologic changes of infected mammary gland tissues and a number of other organs were evaluated. Complement (C) activation was analysed by immunoelectrophoretic quantification of molecules with C3c epitopes (C3, C3b, iC3b, and C3c) in serum. In all animals the organisms were confined to the mammary glands. Serum C3c levels were significantly higher (P<0.05) in infected untreated BALB/cJ and SCID mice, which also had severe mammary gland tissue inflammation, compared with control mice treated with AmB (4 mg kg(-1) i.p. once daily for 4 days). Both treated and control nude mice showed less tissue inflammation compared to BALB/cJ and SCID mice, and revealed insignificant activation of the complement system. It is concluded that innate immune response is important in the control of candidiasis and that the murine mastitis model is useful for immunopathological studies as well as evaluation of potential antifungal compounds.

Amphotericin B↗
PubMed2000

Attitude of Swedish veterinary and medical students to animal experimentation.

Nearly all veterinary and medical students (94 per cent) found it morally acceptable to use animals in research and believed it to be a necessity in order to treat human diseases. In contrast with the medical students a substantial proportion of veterinary students (40 per cent) considered themselves animal rights activists. Unlike the medical curriculum, the veterinary curriculum contains a two-week course in laboratory animal medicine, and a higher proportion of the students who had not been through this course was opposed to the use of animals in research than of the students who had completed the course. The course modified the views of half the students; more than 26 per cent of them became more positive towards animal use in research after the course, whereas 3 per cent became more negative.

Adult↗
PubMed2000

Determination of the plant growth regulator chlormequat in food by liquid chromatography-electrospray ionisation tandem mass spectrometry.

A confirmatory method for the determination of trace levels of chlormequat in a variety of different food matrices was developed. It entails a single clean-up step over a solid-phase cation exchange resin and subsequent liquid chromatography-electrospray ionisation tandem mass spectrometry using a stable isotopically labelled internal standard. Mass spectral acquisition was done in selected reaction monitoring mode, selecting the transitions from both the 35Cl and the 37Cl isotope of chlormequat. Recoveries after extraction and clean-up, determined with radio-labelled chlormequat and averaged over the spiking range (16-65 microg kg(-1)) in four different commodities, were within 88-96%, with a coefficient of variation better than 8%. The method can be applied to pears, pear juice concentrates, fruit purées, and cereal products, with typical limits of detection for chlormequat estimated at 2-5 microg kg(-1). A survey of different food commodities revealed that chlormequat was detectable--albeit at very low levels--in many of the food samples analysed, with the highest concentration recorded in pears purchased in Switzerland and of South African origin (5.5 mg kg(-1)). Measurements were also conducted on two LC-MS instruments and demonstrate the versatility and robustness of the method and its applicability to instruments of different ion source design.

Calibration↗
PubMed2000

Students' acceptance of clinical xenotransplantation.

The aim of this study was to elucidate undergraduate university students' views on clinical xenotransplantation. A total of 1875 students from eight faculties at Uppsala University and the Swedish University of Agricultural Sciences answered a questionnaire. Three out of four respondents would be prepared to receive a transplant from an animal on medical grounds if necessary. Forty percent had signed an organ donation card. There was no difference in attitude between those who had signed an allotransplantion card and those who had not. According to gender, age, length of university program, and faculty, results showed that a higher proportion of those who approved were male, young, and studying on programs longer than three years; also, they were more likely to study programs in the Faculties of Agriculture and Pharmacy. At the Medical Faculty, nursing students seemed to be less approving, compared to future biomedical analysts, biomedical scientists, and physicians. The acceptance of xenotransplantation also tended to be positively associated with morally accepting and understanding the use of animals in biomedical research, the approval of euthanasia, the approval of early abortion, and the use of human fetuses in research, as well as clinical testing of humans.

Adult↗
PubMed2000

Adrenal cortex and stomach lesions associated with stress in wild male African green monkeys (Cercopithecus aethiops) in the post-capture period.

The objective of this study was to look for early pathological changes in stress target organs, adrenal glands, and stomachs in captured wild African green monkeys (AGMs). Three wild-caught male AGMs and seven singly housed wild AGMs were euthanized on day 1 and day 45 post-capture, respectively, and compared with four wild males euthanized with a rifle as controls. Morphometric analyses of the adrenal cortices and the cortical zones were done using an image analyzer. By day 45, the confined animals were clinically healthy, but had lost 47% mean body weight despite ad libitum feeding. The width of zona fasciculata in the controls was significantly smaller compared with that of 45-day monkeys (P < 0.05). Numerous acidophilic, hyperplastic and hypertrophic cells were present in the zona fasciculata of the 1-day confined AGMs. In the 45-day monkeys, there was glandular hyperplasia in the zona glomerulosa and the acini were distended and vacuous; yellow, granular pigmentation was distributed in the zona fasciculata. Acute stomach lesions represented by petechiation were seen in one monkey on day 1. Deep, circular, mucosal erosions, one to five in number and measuring from 0.5 to 1 mm in diameter, were present in three monkeys on day 45 post-capture. There were no adrenal cortex or stomach lesions in the rifle-shot monkeys. In conclusion, pathological lesions in the adrenal glands, and stomachs of the wild AGMs and weight loss occurred within the initial 45-day period following capture and confinement.

Adrenal Glands↗
PubMed2000

Schistosoma mansoni in mice: the pattern of primary cercarial exposure determines whether a secondary infection post-chemotherapy elicits a T helper 1- or a T helper 2-associated immune response.

Reinfection with Schistosoma mansoni following chemotherapy often results in an ameliorated granulomatous reaction and hence a mild disease. This study examined some of the immunological mechanisms that could be associated with this residual protection. BALB/c mice were infected with either a single dose (group A) of 100 S. mansoni cercariae or with 10 doses of 10 cercariae each (group B) given at 3-day intervals. The mice were treated with praziquantel 8 weeks postinfection and, 2 weeks later, together with another group of naive mice (group C), they were infected with a single dose of 100 cercariae each. All the animals were killed 8 weeks later and schistosome egg antigen (SEA)- and soluble adult worm antigen preparation (SWAP)-induced cytokine recall responses in splenocytes, as well as serum immunoglobulin levels, were quantified and hepatic granuloma sizes measured. Group A animals had higher levels of SEA-induced interferon-gamma (IFN-gamma) but lower levels of interleukin (IL)-5 than groups B and C (P < 0.01). Group B animals had low SEA-induced IFN-gamma levels and elevated IL-5 levels, although these were lower than group C. SEA-induced IL-10 was low in both groups A and B as compared to group C (P < 0.01). SWAP was less effective as an inducer of splenocyte cytokine production than SEA but both SWAP-induced IFN-gamma and IL-5 were detected in groups A and C. SEA- and SWAP-specific immunoglobulin E (IgE) and immunoglobulin G (IgG) titres were not significantly different between the three groups. Granuloma diameters were larger in group C (mean 297 +/- 51.3 microm) as compared to groups A (174 +/- 49 microm, P < 0.01) and B (247.5 +/- 44 microm, P < 0.05). Taken together, these results demonstrate that granuloma size is reduced during a reinfection exposure compared with a primary infection. This reduction is associated with a T helper 1 response in mice exposed to a single large dose of cercariae in the primary infection and with a predominantly T helper 2 response in those infected with multiple small doses.

Animals↗