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Biomedical subjects

M Kristensen

Publications and source records attributed to M Kristensen.

At least 19 recordsLinked to original sources

Appropriate treatment of malaria? Use of antimalarial drugs for children's fevers in district medical units, drug shops and homes in eastern Uganda.

OBJECTIVE: To evaluate the quality of pharmaceutical care of malaria for children in eastern Uganda prescribed at government health units and drug shops, and administered by caretakers at home; and to assess its appropriateness in relation to national treatment guidelines, which recommend chloroquine over 3 days. METHODS: We followed 463 children under 5 years whose caretakers attended two drug shops and two government health units to seek treatment for fever. The children were examined and the caretakers interviewed on the day of enrollment in the study (day 0), and in their homes on days 3 and 7. Data was collected on drug use prior to attending the shop or health unit, the treatment provided at these study sites, and the administration of drugs at home over the following 3 days. RESULTS: Before attending the study sites, 72% of children had already been given some biomedical drugs, and 40% had received the recommended drug, chloroquine. Health workers prescribed chloroquine for 94% of the children, but only 34% of the recommended doses followed guidelines. Two-thirds of the children were prescribed an injection of chloroquine. By day 3, according to caretaker reports, about 38% of the children had received chloroquine in compliance with the instructions given by the health workers and drug shop attendants. Only 28% of the children had received chloroquine at the optimal dose of 20-30 mg/kg recommended by national policy. CONCLUSION: The methods were useful for examining adherence of both caretakers and health care providers to national guidelines and the extent to which caretakers were compliant with providers' prescriptions. Chloroquine and antipyretics were the drugs of choice for fever in these areas of rural eastern Uganda. But children did not receive the recommended dosage of chloroquine because of lack of compliance on the parts of providers as well as users of health care.

Administration, Oral↗

Identification and characterization of mutations in housefly (Musca domestica) acetylcholinesterase involved in insecticide resistance.

Acetylcholinesterase (AChE) insensitive to organophosphate and carbamate insecticides has been identified as a major resistance mechanism in numerous arthropod species. However, the associated genetic changes have been reported in the AChE genes from only three insect species; their role in conferring insecticide insensitivity has been confirmed, using functional expression, only for those in Drosophila melanogaster. The housefly, Musca domestica, was one of the first insects shown to have this mechanism; here we report the occurrence of five mutations (Val-180-->Leu, Gly-262-->Ala, Gly-262-->Val, Phe-327-->Tyr and Gly-365-->Ala) in the AChE gene of this species that, either singly or in combination, confer different spectra of insecticide resistance. The baculovirus expression of wild-type and mutated housefly AChE proteins has confirmed that the mutations each confer relatively modest levels of insecticide insensitivity except the novel Gly-262-->Val mutation, which results in much stronger resistance (up to 100-fold) to certain compounds. In all cases the effects of mutation combinations are additive. The mutations introduce amino acid substitutions that are larger than the corresponding wild-type residues and are located within the active site of the enzyme, close to the catalytic triad. The likely influence of these substitutions on the accessibility of the different types of inhibitor and the orientation of key catalytic residues are discussed in the light of the three-dimensional structures of the AChE protein from Torpedo californica and D. melanogaster.

Acetylcholinesterase↗

The status and development of insecticide resistance in Danish populations of the housefly Musca domestica L.

Samples of housefly (Musca domestica) field populations were collected from Danish livestock farms in 1997. The tolerance of the first-generation offspring was determined for a number of insecticides. Dose-response values were obtained by topical application for the pyrethroids bioresmethrin and pyrethrum, both synergised with piperonyl butoxide, and the organophosphate dimethoate. The organophosphates azamethiphos and propetamphos and the carbamate methomyl were tested in discriminating dose feeding bioassays. Resistance was low to moderate in most of the populations for most of the compounds tested, but this study also revealed the existence of high resistance to pyrethroid, organophosphate and carbamate insecticides in some populations. The resistance factors at LD50 for bioresmethrin/piperonyl butoxide ranged between 2 and 98, and for pyrethrum/piperonyl butoxide between 2 and 29. Our results indicate that pyrethroid resistance in Denmark is increasing, since four of the 21 farms showed more than 100-fold resistance at LD95, a level of resistance only observed once before. Resistance factors at LD50 for dimethoate ranged from 9 to 100, and showed two distinct trends: populations with either decreasing or increasing resistance. Resistance to azamethiphos was found to be widespread and high. Although two strains with high methomyl and propetamphos resistance were observed, methomyl and propetamphos resistance is moderate and appears not to be increasing.

Animals↗

Shared experience in 13 local Danish EPR projects: the Danish EPR Observatory.

In 1996 a national strategy for the development of electronic patient records (EPR) for the Danish hospitals and primary care was launched. An element in the strategy was to support a number of regional EPR development projects. The EPR-Observatory has in the two recent years collected data from the regional projects, dealing with the expectations in four areas: 1) Impact on organisational issues, 2) Benefits of EPR, 3) Integration of EPR with other information systems and 4) security aspects of EPR. Among the observations an increasing teamwork and im-proved knowledge about the patient was found. What was expected, but not found, was resistance to EPR, as a result of changes in skills and power. The most obvious benefits are increased data accessibility and improved decision ma-king. The most considerable disadvantage is an enormous growth in discontent with the systems performance and the fact, that all the projects are delayed. Many different types of integration solutions are chosen, because of a lack of a common model for integration. Generally the projects find, that EPJ yields increased security, but logistical problems arise in having the systems running 24 hours 7 days a week. Economical benefits cannot be documented. This relates to the fact, that the regional projects are stand-alone projects. The ongoing growth in discontent with the EPR-systems and the fact, that all the projects are delayed must be subject to further exploration.

Attitude to Computers↗

Selection and reversion of azamethipos-resistance in a field population of the housefly Musca domestica (Diptera: Muscidae), and the underlying biochemical mechanisms.

The organophosphorus insecticide, azamethiphos, is widely used throughout the world to control the housefly, Musca domestica (L.). Since its commercial introduction to Denmark in 1983 for this purpose, we have monitored the toxicity of azamethiphos to housefly populations at livestock farms throughout the country and carried out regular field studies. The findings of our field studies, which have revealed a strong potential for resistance development, have been born out by regular surveys showing that resistance has increased in recent years. Through the analysis of a field derived laboratory strain, we have implicated oxidative and hydrolytic mechanisms together with altered acetylcholinesterase in this resistance. Our field and laboratory studies have also indicated that resistance is relatively unstable, and can revert in the absence of selection. The implications of our findings for the continued efficacy of azamethiphos are discussed.

Acetylcholinesterase↗

Technological changes in the healthcare sector. A method to assess change readiness.

This paper describes the theory, method and recent results of a study developing methods for assessment of change readiness. The empirical focus is on development and implementation of clinical IT systems in the Danish healthcare sector. To assess change readiness, a questionnaire has been developed. The questionnaire has been tested in a hospital department as a part of a pre analysis related to development and implementation of an IT quality assurance system. The study shows a general positive attitude to the IT system and the organisational changes, related to the implementation and use of the system. It also supplies the project organisation with specific information, useful to the project organisation to continue the essential dialogue with the healthcare professionals during the change process. Furthermore it provides a useful tool for planning the ongoing developing processes. Several other healthcare organisations are at the moment entering the study.

Attitude to Computers↗

The Danish EPR Observatory. Assessing organisational impact from EPR implementation.

The EPR Observatory has studied 13 local Danish electronic patient record (EPR) projects through 2 years. The focus has been on expectations and experiences in relation to organisational changes. The main conclusions are that the healthcare professionals, working with the development, implementation and/or use of EPR, are in a very important and difficult process settling up with old traditions and cultures tied to the healthcare professions. Especially the healthcare professionals, working with EPR, shows interest and readiness to participate in new ways of collaboration and to work with highly structured data in structured frameworks. EPR is at this point of time only diffused in few relatively small and isolated healthcare organisations, and the preliminary assessment in the study only outlines the perspectives for what will happen on a wider scale when EPR systems get more diffused.

Denmark↗

Isolation and characterization of the gene encoding the starch debranching enzyme limit dextrinase from germinating barley.

The gene encoding the starch debranching enzyme limit dextrinase, LD, from barley (Hordeum vulgare), was isolated from a genomic phage library using a barley cDNA clone as probe. The gene encodes a protein of 904 amino acid residues with a calculated molecular mass of 98.6 kDa. This is in agreement with a value of 105 kDa estimated by SDS-PAGE. The coding sequence is interrupted by 26 introns varying in length from 93 bp to 825 bp. The 27 exons vary in length from 53 bp to 197 bp. Southern blot analysis shows that the limit dextrinase gene is present as a single copy in the barley genome. Gene expression is high during germination and the steady state transcription level reaches a maximum at day 5 of germination. The deduced amino acid sequence corresponds to the protein sequence of limit dextrinase purified from germinating malt, as determined by automated N-terminal sequencing of tryptic fragments coupled with matrix assisted laser desorption mass spectrometry. The sequenced peptide fragments cover 70% of the entire protein sequence, which shows 62% and 77% identity to that of starch debranching enzymes from spinach and rice and 37% identity to Klebsiella pullulanase. Sequence alignment supports the multidomain architecture and identifies both secondary structure elements of the catalytic (beta/alpha)8-barrel substrate, catalytic residues, and specificity associated motifs characteristic of members of the glycoside hydrolase family 13 which cleave alpha-1,6-glucosidic bonds. A remarkable distribution of the secondary structure elements to individual exons is observed.

Amino Acid Sequence↗

Preserved arterial flow secures hepatic oxygenation during haemorrhage in the pig.

1. This study examined the extent of liver perfusion and its oxygenation during progressive haemorrhage. We examined hepatic arterial flow and hepatic oxygenation following the reduced portal flow during haemorrhage in 18 pigs. The hepatic surface oxygenation was assessed by near-infrared spectroscopy and the hepatic metabolism of oxygen, lactate and catecholamines determined the adequacy of the hepatic flow. 2. Stepwise haemorrhage until circulatory collapse resulted in proportional reductions in cardiac output and in arterial, central venous and pulmonary wedge pressures. While heart rate increased, pulmonary arterial pressure remained stable. In addition, renal blood flow decreased, renal vascular resistance increased and there was elevated noradrenaline spill-over. Further, renal surface oxygenation was lowered from the onset of haemorrhage. 3. Similarly, the portal blood flow was reduced in response to haemorrhage, and, as for the renal flow, the reduced splanchnic blood flow was associated with an elevated noradrenaline spill-over. In contrast, hepatic arterial blood flow was only slightly reduced by haemorrhage, and surface oxygenation did not change. The hepatic oxygen uptake was maintained until the blood loss represented more than 30 % of the estimated blood volume. At 30 % reduced blood volume, hepatic catecholamine uptake was reduced, and the lactate uptake approached zero. 4. Subsequent reduction of cardiac output and portal blood flow elicited a selective dilatation of the hepatic arterial vascular bed. Due to this dilatation liver blood flow and hepatic cell oxygenation and metabolism were preserved prior to circulatory collapse.

Animals↗

The Extended Staff Observation Aggression Scale (SOAS-E): development, presentation and evaluation.

The Staff Observation Aggression Scale (SOAS) was developed as a scale for reporting aggressive incidents involving psychiatric in-patients. The SOAS -- Extended Version (SOAS-E) has the same aim, but has additional categories and subcategories. The SOAS-E clearly distinguishes between violent and non-violent aggressive behaviour and characterizes in more detail the associated situation. However, the main contribution of the SOAS-E is the introduction of a category of 'warning signals' that precede the releasing 'provocation factor' as a separate and primary aspect of the cyclus of aggressive incidents. The development of the SOAS-E is described, and the testing and inter-rater reliability of the warning signals category are examined. Compared to the SOAS, the additional categories of the SOAS-E are found to increase the scope for a detailed characterization of aggressive behaviour in psychiatric wards.

Adult↗

Major foot trauma: the dilemma of reconstruction versus amputation.

Advances in medicine and surgery have allowed for dramatic improvements in the management of severe foot trauma. Some salvage attempts have led patients to repeated hospitalizations, extensive complications, and a poor functional outcome. The decision for an early amputation versus salvage of the foot remains a difficult one. Two case studies from Loyola University Medical Center and the current predictive indices for limb salvage are reviewed in this chapter.

Adult↗

[Abnormal flora in the small intestine. Diagnostic evaluation of the H2 breath test].

Jejunal aspiration in order to diagnose intestinal bacterial overgrowth is more unpleasant for patients than breath testing. The object of this study was to compare the results of the glucose H2 breath test and the lactulose H2 breath test with the results of intestinal culture. On separate days, cultures of intestinal fluid collected from the Treitz region, glucose H2 breath tests (80 g glucose) and lactulose H2 breath tests (15 g lactulose) were undertaken in 20 patients with diseases predisposing to small intestinal bacterial overgrowth and in 20 controls. Twelve patients had bacterial overgrowth. Abnormal glucose H2 breath tests were observed in 11 patients, ten of whom had bacterial overgrowth. Glucose H2 breath tests were normal in seven out of eight patients without bacterial overgrowth. Only four patients had an abnormal lactulose H2 breath test. It is concluded that the glucose H2 breath test is acceptable for diagnosing bacterial overgrowth, whereas the lactulose H2 breath test in not.

Adult↗