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Reichardt M, Moller Jensen P, Andersen Dahl V, Bjorholm Dahl A, Ackermann M, Shah H, Länger F, Werlein C, Kuehnel MP, Jonigk D, Salditt T. 3D virtual histopathology of cardiac tissue from Covid-19 patients based on phase-contrast X-ray tomography. eLife 2021; 10:e71359. [PMID: 34930527 PMCID: PMC8747495 DOI: 10.7554/elife.71359] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2021] [Accepted: 12/10/2021] [Indexed: 11/29/2022] Open
Abstract
For the first time, we have used phase-contrast X-ray tomography to characterize the three-dimensional (3d) structure of cardiac tissue from patients who succumbed to Covid-19. By extending conventional histopathological examination by a third dimension, the delicate pathological changes of the vascular system of severe Covid-19 progressions can be analyzed, fully quantified and compared to other types of viral myocarditis and controls. To this end, cardiac samples with a cross-section of 3.5mm were scanned at a laboratory setup as well as at a parallel beam setup at a synchrotron radiation facility the synchrotron in a parallel beam configuration. The vascular network was segmented by a deep learning architecture suitable for 3d datasets (V-net), trained by sparse manual annotations. Pathological alterations of vessels, concerning the variation of diameters and the amount of small holes, were observed, indicative of elevated occurrence of intussusceptive angiogenesis, also confirmed by high-resolution cone beam X-ray tomography and scanning electron microscopy. Furthermore, we implemented a fully automated analysis of the tissue structure in the form of shape measures based on the structure tensor. The corresponding distributions show that the histopathology of Covid-19 differs from both influenza and typical coxsackie virus myocarditis.
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Affiliation(s)
- Marius Reichardt
- Institut für Röntgenphysik, Georg-August-Universität Göttingen, Friedrich-Hund-PlatzGöttingenGermany
| | | | | | | | - Maximilian Ackermann
- Institute of Anatomy and Cell Biology, University Medical Center of the Johannes Gutenberg-University MainzMainzGermany
| | - Harshit Shah
- Medizinische Hochschule Hannover (MHH)HannoverGermany
- Deutsches Zentrum für Lungenforschung (DZL), Hannover (BREATH)HannoverGermany
| | - Florian Länger
- Medizinische Hochschule Hannover (MHH)HannoverGermany
- Deutsches Zentrum für Lungenforschung (DZL), Hannover (BREATH)HannoverGermany
| | | | - Mark P Kuehnel
- Medizinische Hochschule Hannover (MHH)HannoverGermany
- Deutsches Zentrum für Lungenforschung (DZL), Hannover (BREATH)HannoverGermany
| | - Danny Jonigk
- Medizinische Hochschule Hannover (MHH)HannoverGermany
- Deutsches Zentrum für Lungenforschung (DZL), Hannover (BREATH)HannoverGermany
| | - Tim Salditt
- Institut für Röntgenphysik, Georg-August-Universität Göttingen, Friedrich-Hund-PlatzGöttingenGermany
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Stuart MB, Jensen PM, Olsen JTR, Kristensen AB, Schou M, Dammann B, Sorensen HHB, Jensen JA. Real-Time Volumetric Synthetic Aperture Software Beamforming of Row-Column Probe Data. IEEE Trans Ultrason Ferroelectr Freq Control 2021; 68:2608-2618. [PMID: 33830920 DOI: 10.1109/tuffc.2021.3071810] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Two delay-and-sum beamformers for 3-D synthetic aperture imaging with row-column addressed arrays are presented. Both beamformers are software implementations for graphics processing unit (GPU) execution with dynamic apodizations and third-order polynomial subsample interpolation. The first beamformer was written in the MATLAB programming language and the second was written in C/C++ with the compute unified device architecture (CUDA) extensions by NVIDIA. Performance was measured as volume rate and sample throughput on three different GPUs: a 1050 Ti, a 1080 Ti, and a TITAN V. The beamformers were evaluated across 112 combinations of output geometry, depth range, transducer array size, number of virtual sources, floating-point precision, and Nyquist rate or in-phase/quadrature beamforming using analytic signals. Real-time imaging defined as more than 30 volumes per second was attained by the CUDA beamformer on the three GPUs for 13, 27, and 43 setups, respectively. The MATLAB beamformer did not attain real-time imaging for any setup. The median, single-precision sample throughput of the CUDA beamformer was 4.9, 20.8, and 33.5 Gsamples/s on the three GPUs, respectively. The throughput of CUDA beamformer was an order of magnitude higher than that of the MATLAB beamformer.
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Hossain ZZ, Ferdous J, Tulsiani SM, Jensen PM, Begum A. Quantitative Analysis of Nucleic Acid Extraction Methods for Vibrio cholerae Using Real-time PCR and Conventional PCR. Mymensingh Med J 2018; 27:327-335. [PMID: 29769498] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
The devastating diarrheal disease cholera is caused by the bacterium Vibrio cholerae. Nucleic acid extraction is the primary step for several molecular detection approaches. In order to identify the sources of cholera illness, an efficient, fast and easy DNA extraction method for toxigenic Vibrio cholerae is desired which can be applied on diverse type of samples. This methodology developmental setup study was performed in the Environmental Microbiology Lab, Department of Microbiology, University of Dhaka, Bangladesh from March 2015 to May 2015 attempted to compare three DNA extraction methods for efficient detection and quantification of Vibrio cholerae. Three nucleic acid extraction methods: (Boiled template, Phenol: Chloroform: Isoamyl alcohol, QiaAmp® mini kit), were assessed for four, routinely tested, templates: crude culture, suspension in water, phosphate buffer saline (PBS), and food by conventional and real time PCR targeting the toxin-coding ctxA gene. Finally, the results were compared in context of processing time and overall cost. Cycle threshold (Ct) values were within acceptable parameters by real time PCR (5 to 35 cycles). All the three extraction methods produced sufficient yield of DNA and copy number for detection by real time and conventional PCR. The boiled template method for water samples yielded low amount of DNA in comparison to the other methods, and is therefore sensitive to detect by non-quantitative, conventional PCR only. Despite an overall low detectability from water samples, our comparison reveals that the boiled template method is the most suitable method for high quality and quantity pathogenic DNA particularly in light of limited access to expensive kits and reagents, time constraints, and high sample load.
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Affiliation(s)
- Z Z Hossain
- Zenat Zebin Hossain, PhD Student, Department of Microbiology, University of Dhaka, Dhaka 1000, Bangladesh
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Harries AD, Jensen PM, Zachariah R, Rusen ID, Enarson DA. How health systems in sub-Saharan Africa can benefit from tuberculosis and other infectious disease programmes. Int J Tuberc Lung Dis 2009; 13:1194-1199. [PMID: 19793422] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/28/2023] Open
Abstract
Weak and dysfunctional health systems in low-income countries, particularly in sub-Saharan Africa, are recognised as major obstacles to attaining the health-related Millennium Development Goals by 2015. Some progress is being made towards achieving the targets of Millennium Development Goal 6 for tuberculosis (TB), HIV/AIDS and malaria, with the achievements largely resulting from clearly defined strategies and intervention delivery systems combined with large amounts of external funding. This article is divided into four main sections. The first highlights the crucial elements that are needed in low-income countries in sub-Saharan Africa to deliver good quality health care through general health systems. The second discusses the main characteristics of infectious disease and TB control programmes. The third illustrates how TB control and other infectious disease programmes can help to strengthen these components, particularly in human resources; infrastructure; procurement and distribution; monitoring, evaluation and supervision; leadership and stewardship. The fourth and final section looks at progress made to date at the international level in terms of policy and guidelines, with some specific suggestions about this might be moved forward at the national level. For TB and other infectious disease programmes to drive broad improvements in health care systems and patient care, the lessons that have been learnt must be consciously applied to the broader health system, and sufficient financial input and the engagement of all players are essential.
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Affiliation(s)
- A D Harries
- International Union Against Tuberculosis and Lung Disease, Paris, France.
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Vennestrøm J, Egholm H, Jensen PM. Occurrence of multiple infections with different Borrelia burgdorferi genospecies in Danish Ixodes ricinus nymphs. Parasitol Int 2007; 57:32-7. [PMID: 17804280 DOI: 10.1016/j.parint.2007.07.004] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2006] [Revised: 07/17/2007] [Accepted: 07/19/2007] [Indexed: 10/23/2022]
Abstract
The pathogen Borrelia burgdorferi causes Lyme Borreliosis in human and animals world-wide. In Europe the pathogen is transmitted to the host by the vector Ixodes ricinus. The nymph is the primary instar for transmission to humans. We here study the infection rate of five Borrelia genospecies: B. burgdorferi sensu stricto, B. afzelii, B. garinii, B. valaisiana, B. lusitaniae in nymphs, by IFA and PCR. 600 nymphs were collected in North Zealand of Denmark. Each nymph was first analysed by IFA. If positive for spirochaetal infection, the genospecies was determined by PCR. The infection rate of B. burgdorferi sensu lato was 15.5%, with the primary genospecies being B. afzelii (64.3%), B. garinii (57.1%), and B. lusitaniae (26.8%). It is the first time B. lusitaniae is documented in Denmark. Even though, the highest infection rate was discovered for B. afzelii and B. garinii, mixed infections are more common than single infections. Fifty-one percent (29/56) of these were infected with two genospecies, 7.1% (4/56) with three, and 5.3% (3/56) with four. We try to explain the high infection rate and the peculiar number of multiple infections, with a discussion of changes host abundance and occurrence of different transmission patterns.
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Affiliation(s)
- J Vennestrøm
- Section for Genetics and Microbiology, Department of Ecology, The Royal Veterinary and Agricultural University, Frederiksberg, Denmark.
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Vennestrøm J, Jensen PM. Ixodes ricinus: the potential of two-dimensional gel electrophoresis as a tool for studying host-vector-pathogen interactions. Exp Parasitol 2006; 115:53-8. [PMID: 16904668 DOI: 10.1016/j.exppara.2006.05.008] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2006] [Revised: 05/25/2006] [Accepted: 05/29/2006] [Indexed: 11/16/2022]
Abstract
Ixodes ricinus is a three-host tick, with three active instars. For moulting to occur the tick has to find a host where it can take a blood meal. Throughout feeding I. ricinus can be infected or infect the host with different pathogens, e.g., Tick-Borne Encephalitis virus or Borrelia burgdorferi. The host-vector-pathogen interaction is very complex, making a detailed study difficult. Here we analyse the potential of two-dimensional gel electrophoresis (2DE) to study the host-vector-pathogen interaction. We examined 20 nymphs, which as larvae parasitised either mouse or hen. After moulting, they were kept alive for up to 30 weeks, to analyse whether tick ageing influenced host determination, and for comparison of the 2D-gels. Even though the number of proteins in the gel decreased during ageing, some proteins of the host determination persisted for all 30 weeks. We also discovered persisting proteins in relation to nymphs. These findings showed that 2DE is suitable as a tool for studying host-vector-pathogen interactions.
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Affiliation(s)
- J Vennestrøm
- Department of Genetics and Microbiology, The Royal Veterinary and Agricultural University, Frederiksberg, Denmark.
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Abstract
The tick Ixodes ricinus (L.) is a known vector of several zoonotic diseases such as Tick Borne Encephalitis (TBE), Lyme borreliosis and ehrlichiosis. The interaction between humans and ticks are at the very core of our understanding of the epidemiology of tick borne zoonoses, but only few experimental studies have been performed. Hence our understanding of the epidemiology of tick-borne disease has to rest on the assumption that the potential tick activity, which is reflected in tick samples from the vegetation or samples from animals, corresponds with tick-human interaction. Observations which may reflect the long term tick-human contact are available in Denmark. These observations are records of requests for information on I. ricinus forwarded to the Danish Pest Infestation Laboratory (DPIL). This article was based on the assumption that the request could be seen as a measure of tick-human interaction reflecting the tick densities in relative terms. The perceived tick densities given by the number of requests on I. ricinus divided by the total number of requests to DPIL was fairly stable from 1965 to 1985, while it doubled during the late 1980's reaching a higher level in the beginning of the 1990's. The perceived density was well explained by the variation in temperature, solar radiation (monthly measurement) and deer abundance (yearly assessments). The measure of deviation, i.e. the ratio between observed requests + 1 and modelled requests + 1, for the individual years varied between 0.91 and 1.20, with considerable within-year variation. A gradual change in periodicity of the residual might suggest gradually changing tick population dynamics. In conclusion, the perceived tick densities appear to be consistent with the current knowledge of tick ecology and tick-transmitted diseases.
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Affiliation(s)
- P M Jensen
- Zoology Section, Department of Ecology, The Royal Veterinary and Agricultural University, Thorvaldsensvej 40, DK-1871 Frederiksberg, Denmark.
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Jensen PM, Kaufmann U. Seasonal and diel activity of Ixodes ricinus (Acari: Ixodidae) subpopulations in Denmark. Aspects of size, physiological age, and malate dehydrogenase genotype in a forest site without any undergrowth. Exp Appl Acarol 2003; 30:289-303. [PMID: 14756394 DOI: 10.1023/b:appa.0000006515.66461.32] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
UNLABELLED The underlying population dynamics and the behavioural patterns of the vectors are key issues in understanding the transmission of vector borne pathogens. For the tick Ixodes ricinus both seasonal and diel activity have been described as bimodal patterns, which in seasonal aspect has been interpreted as representing two cohorts. However, recent studies have shown that this interpretation may be incorrect. The aim of this study was to obtain more detailed information on nymph host seeking by studying subpopulations of ticks during the day and season. The study was designed to allow for comparisons of the diel variation and seasonal variation in their dependency in a number of tick characteristics. The study took place in a forest with planted beech trees without any undergrowth. Ticks were collected by flagging the dead leaves on the forest floor. For each nymph, a number of visual observations were made. The size and physiological age was observed and the nymphs were genotyped in the malate dehydrogenase locus (MDH, E.C. 1.1.1.37). Briefly the main results can be given as: (i) There were significant differences in the composition of size classes during the season, but only limited trends in time. (ii) The proportion of the small nymphs was highly variable, with a variation from 3% to 24% in October and September, respectively. (iii) The diel variation in MDH genotypes was significant in May and August. (iv) Nymph size classes and physiological age appeared to interact. The non-random interaction was caused by a relatively even distribution of small nymphs in all four age classes, while large nymphs tended to fall into age class 2 and 3. The length by age interaction for the individual months was noted to be significant in May, July, August and September, but not in June. Similarly the interaction was significant in the morning and afternoon, but not at midday. The overall results describe the seasonal and diel activity patterns as changing systematically for several characteristics under the influence of weather condition and population dynamics. IN CONCLUSION The observations are best interpreted as being produced of a single cohort of ticks, but the revealed complexity of the host seeking activity suggest that measures of activity x abundance should be interpreted very cautiously in relation to population dynamics.
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Affiliation(s)
- P M Jensen
- Zoology Section, Department of Ecology, The Royal Veterinary and Agricultural University Thorvaldsensvej 40, 1871 Frederiksberg, Denmark.
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Grantcharov TP, Bardram L, Jensen PM, Rosenberg J. [Virtual reality-computer simulation as a tool for training and evaluating skills in laparoscopic surgery]. Ugeskr Laeger 2001; 163:3651-3. [PMID: 11445990] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/16/2023]
Affiliation(s)
- T P Grantcharov
- Arhus Universitetshospital, Arhus Kommunehospital, kirurgisk gastroenterologisk afdeling L.
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Abstract
A study of nymphal and adult Ixodes ricinus density was performed in well-defined spruce and beech forest habitats with different levels of roe deer abundance and soil water capacity. In 35 habitats, a total of 489 larvae, 1,611 nymphs and 193 adult I. ricinus ticks were collected. Tick density was found to be influenced by roe deer abundance and soil water capacity. Based on this evaluation, a model predicting increasing number of ticks with increasing roe deer abundance and soil water capacity was suggested. A total of 1,045 nymphs and 106 adult ticks were tested for infection with Borrelia burgdorferi sensu lato Of these, 53 nymphs and 6 adults were found to be infected, leading to an general infection rate of 5% and 6% for nymphs and adults, respectively. Prevalences of Borrelia burgdorferi sensu lato in nymphal I. ricinus were found to be independent of roe deer abundance and soil water capacity. The correlation between human neuroborreliosis incidence and the estimated number of I. ricinus based on roe deer abundance and soil water capacity was examined. Differences in human neuroborreliosis incidence were found to correspond with the expected spatial differences in tick density in 12 counties in Denmark.
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Affiliation(s)
- P M Jensen
- Department of Ecology, The Royal Veterinary and Agricultural University, Copenhagen, Denmark
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Abstract
The prevalence of Borrelia burgdorferi sensu lato in Ixodes ricinus nymphs in Denmark was found to be approximately 5%. The mean abundance of infected nymphs varied from 0.3 to 4.4 per 100 m2 according to site. The seasonal occurrence of infected nymphs in a beech forest coincided with seasonal distribution of neuroborreliosis cases. In order to establish a working hypothesis, it was assumed that the availability of habitats and human habitat preferences is one of the factors leading to low number of neuroborreliosis cases in the spring. In addition, this paper gives a description of the neuroborreliosis cases in Denmark in the period 1985-97 and offers a possible explanation for the variation in cases. The explanation is based on an assessment of tick density, which by comparison with the number of neuroborreliosis cases provides information on the infectivity of ticks. The model suggests that high temperatures and low precipitation in the autumn is essential for the transmission of B. burgdorferi sensu lato to reservoir hosts or development of B. burgdorferi sensu lato within ticks, which secures high tick infectivity in the following season.
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Affiliation(s)
- P M Jensen
- Department of Ecology, The Royal Veterinary and Agricultural University, Copenhagen, Denmark
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Alekseev AN, Jensen PM, Dubinina HV, Smirnova LA, Makrouchina NA, Zharkov SD. Peculiarities of behaviour of taiga (Ixodes persulcatus) and sheep (Ixodes ricinus) ticks (Acarina: Ixodidae) determined by different methods. Folia Parasitol (Praha) 2001; 47:147-53. [PMID: 10945740 DOI: 10.14411/fp.2000.029] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
A comparison of the behavioural peculiarities of Ixodes persulcatus Schulze, 1930 (north-western population, Russia) and Ixodes ricinus (L., 1758) from western Russia and Denmark was determined by using two methods. Method 1 involved a sojourn of ticks on vertical plastic sticks and showed that the questing behaviour of I. ricinus nymphs was dependent on temperature and relative humidity (RH). A significantly greater number of nymphs quested at 22 degrees C and 100% RH than at 18 degrees C. When the humidity was reduced to 30% all of the nymphs departed. In the second method, the activity of ticks on an inclined "ticksdrome" was estimated. The activity of I. ricinus adults from the Danish population was 1.2 times greater than that of ticks from Russia. Females of the species studied and specimens from all study areas were more active than all other stages of development. The locomotor activity of both adult and immature I. ricinus that were infected with Borrelia burgdorferi sensu lato was suppressed when compared with uninfected specimens. The locomotor activity of I. persulcatus females infected by borreliae with exoskeleton anomalies was 1.3 times greater (P<0.05) than that of infected ticks without anomalies. Our data showed that infected females with exoskeleton anomalies could crawl faster on a human and reach uncovered parts of the body that are vulnerable for attachment and feeding. A study of locomotor activity and questing behaviour may be useful for comparing the risk for different tick species and populations to transmit tick-borne pathogens.
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Affiliation(s)
- A N Alekseev
- Zoological Institute, Russian Academy of Sciences, St. Petersburg. devana@@HD1389.spb.edu
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Jensen LS, Christiansen PM, Wara P, Jensen PM. [Complications of cholecystectomy before and after introduction of laparoscopic surgery]. Ugeskr Laeger 2001; 163:763-5. [PMID: 11228805] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
Abstract
OBJECTIVES In the University Department of Surgical Gastroenterology, Arhus University Hospital, the frequency of complications to acute and elective cholecystectomy was investigated before and after introduction of laparoscopic cholecystectomy. MATERIAL AND METHODS A retrospective survey turned up 1768 patients in the period of conventional open surgery (1974-1985) and 1432 patients in the laparoscopic period (1991-1998). All patients with exploration of the common bile duct were excluded. RESULTS In the open period 12 patients (0.68%) had lesions of the common bile duct requiring reconstruction. In patients operated on with laparoscopic cholecystectomy, lesions of the common bile duct were found in three patients (0.21%) (p = 0.06). Lesions of the cystic duct or an aberrant bile duct occurred in 14 patients (0.79%) during the open period and in 24 patients (1.7%) (p < 0.05) operated on with the laparoscopic technique. Infectious and cardiopulmonary complications were seen in significantly more patients operated on with the open technique. DISCUSSION It is concluded that laparoscopic cholecystectomy offers a safe procedure, although the technique can still be improved, especially with respect to decreasing leakage from the cystic duct.
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Affiliation(s)
- L S Jensen
- Arhus Universitetshospital, Arhus Kommunehospital, kirurgisk gastroenterologisk afdeling L
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Abstract
The seasonality of I. ricinus was studied by three daily consecutive flaggings in four sites situated in an ecotone between a spruce forest and a peaty meadow, a spruce forest, a beech forest and a dense spruce forest. First day flagging samples represent the most commonly used method for description of tick seasonality. Since two consecutive flaggings remove ticks in the vegetation, third day flagging samples represent the number of ticks ascending into the vegetation, which was interpreted as being closely related to the size of the free living tick population. First day samples of nymphs were reasonably consistent with the typical bimodal seasonal pattern of activity (Gray, 1991). Third day samples showed a more stable seasonal development with no or only limited bimodality. The host seeking period or retention time in the vegetation, as defined by the ratio between first and third day samples differed within the season. The host seeking periods were found to be long in the spring, short in midsummer and intermediate in autumn. By analysing the host seeking period for dependency of weather parameters, it was found that host seeking periods primarily depend on relative humidity and solar radiation. No significant difference in tick abundance in third day samples could be related to weather conditions.
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Affiliation(s)
- P M Jensen
- Department for Ecology, The Royal Veterinary and Agricultural University, Frederiksberg, Denmark.
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Abstract
Four different alleles in the nymphal Ixodes ricinus were found for the Malate Dehydrogenase enzyme (MDH). The allele frequency of the MDH genotypes in nymphal I. ricinus was observed to change during the day. Some genotypes were present in the morning, but not in the afternoon and evening. The physiological age of the nymphs was also determined. No significant correlation could be found between physiological age and genotypes. Based on the results it must be anticipated that the comparability of tick samples not only differs in quantity but also in quality for various hours, but not necessarily for various months. Therefore isoenzyme analysis of nymphs at least as regards the MDH alleles appears to be a convenient biological tool to analyse differences in host seeking behaviour.
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Affiliation(s)
- P M Jensen
- Department for Ecology and Molecular Biology, Royal Veterinary and Agricultural University, Denmark
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Abstract
OBJECTIVE We aimed to assess criteria when diagnosing acute otitis media and related performance in general practice in Denmark. Furthermore, we aimed to identify the scale of and the reasons for diagnostic uncertainty. METHODS We conducted: (i) a survey among GPs assessing criteria; and (ii) prospective registration of acute otitis-media-related consultations performed by GPs assessing performance. The survey was sent to all 790 GPs in Funen, North Jutland and Ringkøbing counties, Denmark. A total of 568 (72%) of all GPs in the three counties responded. A total of 368 children with acute otitis media or previous acute otitis media visiting 151 GPs were studied. The main outcome measures were: (i) criteria for symptoms and findings suggesting the diagnosis acute otitis media, criteria for use of equipment and reasons for diagnostic uncertainty; and (ii) prevalence of symptoms and findings in diagnosed cases, equipment used and multivariate analysis of factors predicting diagnostic certainty. RESULTS The symptoms of earache, fever, reduced hearing, findings of bulging eardrum, red eardrum and purulent otorrhea were important criteria used during both diagnosis of acute otitis media by the GPs and assessment of performance. In the prospective study, diagnostic certainty of acute otitis media was 67% (95% CI 58-76) in children under 2 years and 75% (95% CI 69-81) in older children. Diagnostic certainty was statistically related (P < 0.05) to a good view of the eardrum and the findings of purulent otorrhea or a bulging eardrum. Logistic regression revealed that the two most important factors predicting diagnostic certainty were a satisfactory view of the eardrum, with an odds ratio (OR) 11.0 (95% CI 4.1-29.5), and purulent otorrhea OR 10.1 (95% CI 3.1-32.9). Main reasons for diagnostic uncertainty given by GPs were differential diagnostic doubts, insufficient view of the eardrum and lack of knowledge. CONCLUSION Danish GPs' criteria for the diagnosis of acute otitis media were stricter than criteria used internationally. The discrepancy between diagnostic criteria and performance was small. Diagnostic accuracy and certainty could be substantially improved by cleaning the ear canal when needed and by widespread use of pneumatic otoscopy.
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Affiliation(s)
- P M Jensen
- Department of General Practice, University of Aarhus, Denmark
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Adamsen S, Hansen OH, Jensen PM, Schulze S, Stage JG. [Treatment of gallstones in Denmark]. Ugeskr Laeger 1999; 161:170-2. [PMID: 9922704] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/11/2023]
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Abstract
OBJECTIVE To assess implicit criteria (i.e. what the general practitioner (GP) considers good clinical practice) for and performance (i.e. what the GP actually does) with regard to antibiotic treatment of acute otitis media in Danish general practice. DESIGN a) Criteria assessed by survey among general practitioners. b) Performance assessed by prospective registration of consultations with general practitioners related to otitis media. SETTING General practices in three Danish counties. SUBJECTS a) All the GPs in the three countries (n = 790). b) 368 children with acute otitis media. MAIN OUTCOME MEASURES a) Criteria for timing of treatment and first drug of choice for acute otitis media; b) prescribed antibiotics and multivariate analysis of factors predicting antibiotic prescription. RESULTS a) The response rate was 72%. Only 51% (95% CI 47-55) of GPs would give antibiotics to all children with acute otitis media, and 79% (95% CI 76-82) of GPs would use penicillin-V as first drug of choice. b) Seventy-four per cent (95% CI 68-81) of children with acute otitis media were given antibiotics. Factors predicting the GPs' decision to prescribe antibiotics were the general condition of the child and the factors that are normally used in diagnosing the condition. CONCLUSION Danish general practitioners' criteria for antibiotic treatment of acute otitis media are restrictive, with non-antibiotic treatment in cases of short duration and penicillin-V as first drug of choice. Performance suggests a less restrictive pattern.
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Affiliation(s)
- P M Jensen
- Institute for General Practice, University of Aarhus, Denmark
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Middelfart HV, Jensen PM, Højgaard L, Kehlet H. [Uncomplicated gallstones: who should be operated on?]. Ugeskr Laeger 1997; 159:2992-8. [PMID: 9190727] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Gallstones are common and occur asymptomatically or symptomatically with or without complications. Treatment is only required for symptomatic gallstones and complications in gallstones. Laparoscopic cholecystectomy is the treatment of choice for symptomatic gallstones and is performed with an increasing frequency. One may fear, that the indications for cholecystectomy have changed, and surgery is now undertaken for a lesser degree of morbidity. Cholecystectomy does not increase life expectancy, and 20-30% of patients cholecystectomized for symptomatic gallstones complain of abdominal pain of unknown origin after the operation. New valid parameters in order to predict which patients will benefit from cholecystectomy are therefore necessary. Symptoms specific to gallstones are not precisely known, and greatest success in treatment seems to be related to the occurrence of severe, often steady pain, of hours' duration, often located in the epigastrium or upper right quadrant, with or without radiation and/or vomiting. Dyspepsia alone is not an indication for cholecystectomy. Psychological vulnerability may predict a poor outcome after cholecystectomy and should lead to reconsideration of the indication for surgery.
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Affiliation(s)
- H V Middelfart
- H:S Hvidovre Hospital, kirurgisk gastroenterologisk afdeling
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20
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Jensen PM, Bardram L, Jensen P, Middelfart HV, Støckel M. [Laparoscopic fundoplication in gastroesophageal reflux]. Ugeskr Laeger 1997; 159:577-81. [PMID: 9045446] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Gastro-oesophageal reflux disease (GORD) is a chronic disorder requiring lifelong medical therapy or surgery. In the present study we evaluated the postoperative course and effect of laparoscopic fundoplication on GORD in 27 patients with a median age of 44 (range 27-73) years. Fifteen were operated on with a Watson procedure, and 12 patients had a Nissen procedure. Median stay and convalescence after surgery was one and 10 days respectively. Three patients had to be converted into open surgery (bleeding: two, unclear anatomy: one). No major complications were seen, but four patients had postoperative complications (stenosis requiring dilatation: one, subcutaneous emphysema: one, wound sepsis: one, hernia: one. The two latter complications were seen in converted patients). Two patients had prolonged dysphagia, and two patients needed slight dietetic advice for gasbloat syndrome. In 25 of 27 patients good control of GORD was accomplished as judged by symptomatology, endoscopy and 24-hour pH measurements. It is concluded that laparoscopic fundoplication offers good control of GORD with few complications, and short hospital stay and convalescence.
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Affiliation(s)
- P M Jensen
- Kirurgisk gastroenterologisk afdeling, Hvidovre Hospital
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21
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Lange A, Bonde-Petersen J, Middelfart HV, Aksglaede KB, Jensen PM, Thommesen P, Schiøtz PO. [24-hour esophageal pH in children]. Ugeskr Laeger 1997; 159:582-4. [PMID: 9045447] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Continuous 24-hour esophageal pH-monitoring was performed in 89 infants. Of 38 patients with respiratory symptoms 74% were found to have a pathological 24-h pH monitoring. The same number of pathological monitorings (71%) were found in 38 patients with clinical symptoms of gastro-oesophageal reflux. We found pathological monitorings in only 25% of eight patients with unusual posturing and five healthy children all had normal monitorings. Gastrooesophageal reflux is common in children with clinical gastrointestinal symptoms as well as in children with respiratory symptoms.
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Affiliation(s)
- A Lange
- Paediatrisk afdeling, Arhus Universitetshospital, Arhus Kommunehospital
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22
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Bardram L, Jacobsen B, Jensen PM, Edvardsen L. [A local course on conventional and laparoscopic surgical techniques. A supplement to surgical education]. Ugeskr Laeger 1995; 157:5845-8. [PMID: 7483063] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
In order to increase the possibilities for learning accurate surgical technique in gastrointestinal surgery, we have established a local course for operative training of the registrars. We used organs from pigs--stomach, intestines and liver/gallbladder. They were collected from the local abattoir with assistance from a vet. Conventional gut anastomosis and gastroenteroanastomosis were performed with "two-layer" and "one-layer" techniques. Laparoscopic cholecystectomy was performed with the liver-gallbladder organ block placed in a "black box", in which the organ was perfused with red fluid--a Pulsatile Organ Perfusion System. The registrars' evaluations of the course were very positive. They all thought that the course gave them opportunities for surgical training that were not available in the busy daily routine. The course now forms part of the education programme for surgical registrars in our department.
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Affiliation(s)
- L Bardram
- Kirurgisk gastroenterologisk afdeling, Hvidovre Hospital, København
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23
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Adamsen S, Hansen OH, Jensen PM, Schulze S, Stage JG, Wara P, Jensen LP. [Laparoscopic cholecystectomy in Denmark. A prospective registration]. Ugeskr Laeger 1995; 157:4449-54. [PMID: 7483024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Laparoscopic cholecystectomy (LC) was introduced in Denmark in 1991, and a prospective case register was established. All departments performing LC agreed to participate. In 1991-1992, 2,415 patients underwent LC in 44 departments. The median number of procedures was 32 (interquartile range 18-58, range 1-370), performed by a median of four surgeons per department (3-5, 1-23). Two hundred and forty-two patients (10%) had acute cholecystitis. Eighteen point five percent had had an ERCP performed prior to LC. The rate of conversion to open operation was 10.5%, occurring significantly more often in acute cholecystitis (25.6%) than in patients with other indications (8.8%) (p < 0.001). Intraoperative cholangiography was used in 22.4%. The median duration of LC was 90 minutes (70-120, 25-415). The postoperative course was without complications in 90.4%. Laparotomy for complications was necessary in 43 patients (2.0%), mainly because of bile leaks. Twelve patients (0.6%) were treated endoscopically for complications. Bile duct injury occurred in 16 patients (0.66%, 95% CI 0.34-0.99%), including three transsections, one stricture, and 12 minor injuries. Six patients (0.25%, 95% CI 0-0.45%), three of whom had procedure-related complications, died postoperatively. All were > or = 72 years of age. Median time to discharge was two days, while median time to resumed work/normal activity was eight days. A comparison with the number of LC registered in the National Patient Register indicates that reporting is complete.
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Affiliation(s)
- S Adamsen
- Dansk Kirurgisk Selskab, Landsregister for Laparoskopisk Kolecystektomi, København
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24
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Abstract
Cigarette smoking is the major addiction of women, the leading cause of women's death, and maternal smoking has substantial negative health effects on children. The majority of smokers quit on their own, but women are more likely than men to seek help, and some prefer women-only programs. Multi-component programs combining cessation techniques with counselling, skills training, and emotional support show the highest quit rates. In this clinical study of a multi-component, eight week cessation program for women, sixty-two percent completed the program and stopped smoking. Over half of these were abstinent six months later, which compares favorably with other women's-only programs in Canada. Based on the literature, we hypothesized that factors related to personal health status, family drug history, current lifestyle and social environment would be the best predictors of program outcome: dropping out of the program, completing the program and quitting smoking, and being abstinent at six months. Over 400 measures of personal and family history, health status, health behavior and social environment were gathered. A multiple regression model using four variables with additive variance and stable parameters explained 48% of the variance in program outcome. These were client's history of asthma, smoking status of the mother when the client was a child, weekly consumption of chocolate and candy, and the number of children the client had. These results identify issues that need to be taken into account when assisting women to quit smoking.
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25
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Frøbert O, Vestergaard H, Jensen PM. [Diagnostic value of upper endoscopy in achalasia of the esophagus]. Ugeskr Laeger 1994; 156:634-6. [PMID: 8184494] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Thirty one patients with achalasia of the oesophagus as diagnosed by manometry between 1978 and 1991 at Aarhus Municipal Hospital (Arhus Kommunehospital) constituted the study group. All had had at least one upper endoscopy prior to oesophageal manometry. At the last endoscopy before manometry the endoscopist had no suspicion of achalasia in 48.4% of the cases. It is concluded, that in patients with dysphagia where an organic cause is excluded by upper endoscopy, oesophageal manometry should be carried out.
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Affiliation(s)
- O Frøbert
- Arhus Kommunehospital, Kirurgisk afdeling L
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26
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Kehlet H, Jensen PM. [Is there to be a renaissance of surgical treatment of ulcers?]. Ugeskr Laeger 1993; 155:2599-603. [PMID: 8212365] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Medical treatment of peptic ulcer disease with H2-blockers has over the last ten years practically replaced surgical treatment of this condition, due to greater patient compliance, high effectivity and negligible side-effects. The treatment is, however, strained by the relatively high cost of medication. Development of techniques for laparoscopic vagotomy, which is associated with a considerably reduced postoperative morbidity and reconvalescence as well as entailing only one to two days hospitalization and a minimal surgical scar, has re-opened the debate on medical versus surgical treatment of ulcers. On the basis of a literature review of risk of ulcer recurrence, risk of ulcer complications, cost and compliance associated with the two types of treatment, it is concluded that surgical treatment of peptic ulcers by laparoscopic parietal cell vagotomy should have a renaissance as regards the treatment of patients, who have frequent recurrences when maintained on ordinary medical treatment. However, the development of new, alternative principles for the cheap, effective and complication-free medical treatment of these patients, for example via elimination of helicobacter pylori infection, will necessitate a re-evaluation as regards the treatment of choice.
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Affiliation(s)
- H Kehlet
- Kirurgisk gastroenterologisk afdeling, Hvidovre Hospital, København
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27
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Jensen PM, Wara P, Bardram L, Stage JG. [Laparoscopic parietal cell vagotomy. Preliminary results]. Ugeskr Laeger 1993; 155:2603-5. [PMID: 8212366] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
The results from 11 laparoscopic parietal cell vagotomies are presented. The procedure could be carried out in all patients. The median day of discharge after the procedure was day 1 (range 1-16), median convalescence time 7 (range 4-50) days. One patient required re-operation due to a perforation at the lesser curvature. This complication is ascribed to the learning phase. If a sufficient reduction in gastric acid secretion can be documented in a larger series of patients, laparoscopic parietal cell vagotomy should be considered a serious alternative to conservative treatment.
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Affiliation(s)
- P M Jensen
- Kirurgisk gastroenterologisk afdeling, Hvidovre Hospital, København
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28
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Jensen SL, Gregersen H, Jensen PM. [Experimental gastrointestinal motility]. Ugeskr Laeger 1993; 155:2328-2330. [PMID: 8346573] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Gastrointestinal motility is a major field of research today; however, despite there being a huge amount of available data in the literature, its exact role as a diagnostic tool has yet to be defined. The purpose of this paper is to describe some of the existing experimental models and methods for conducting motility studies.
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Affiliation(s)
- S L Jensen
- Kirurgisk gastroenterologisk afdeling L, Arhus Kommunehospital
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