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PubMed2004

Body Worlds: clinical detachment and anatomical awe.

If studying anatomy in medical school promotes clinical detachment, how do lay people respond to the crash course in anatomy they receive on visiting the Körperwelten / Body Worlds exhibition? If late modernity's celebration of the living body makes the dead body problematic, how do visitors respond to the aestheticised dead bodies on display? Through examining the written comments of visitors, the article identifies a number of responses. The chief is an elementary scientific gaze in which obvious interest is shown in anatomical details. But because the exhibits are dry, odourless and anonymous, this does not generate the defence of emotional detachment; indeed, among several emotional responses, are fascination and, for some, awe. Body Worlds is less a popularised anatomy lab than a shrine to the human body, a shrine in which medically untrained people can look at the body in new ways.

Adaptation, Psychological↗
PubMed2003

Comparative studies of the cell structures of Mycobacterium leprae and M. tuberculosis using the electron microscopy freeze-substitution technique.

The cell envelope and cytoplasmic architecture of the Mycobacterium leprae Thai-53 strain were examined using the freeze-substitution technique of electron microscopy and compared with those of the M. tuberculosis H37Rv strain. Both strains had similarly multilayered envelope architectures composed of an electron-translucent layer, a peptidoglycan layer and the plasma membrane, from outside to inside. A comparison of the structures of these two mycobacteria revealed that the M. leprae cell was smaller in size and had a thinner peptidoglycan layer than the M. tuberculosis cell. The cell widths measured on electron micrographs were 0.44 microm for M. tuberculosis and 0.38 microm for M. leprae. The peptidoglycan layer of M. leprae was 4-5 nm, while the corresponding layer of M. tuberculosis was 10-15 nm.

Animals↗
PubMed2004

Effect of diode laser and fluoride varnish on initial surface demineralization of primary dentition enamel: an in vitro study.

INTRODUCTION: Previous investigations have demonstrated improved enamel caries resistance after laser irradiation. The purpose of this in vitro study was to assess the caries-preventive potential of 809 nm diode laser treatment of the enamel of primary teeth compared to topical fluoride application. METHODS: Eighty samples of sound primary teeth were embedded in plastic and stored in saline solution. The enamel surface of 80 samples was polished in an area of 2 x 2 mm. These tooth specimens were randomly assigned to one control and three test groups: (1) no treatment/control; (2) application of 0.1 mg of fluoride varnish (Duraphat) for 6 h; (3) diode laser application (809 nm, 140 mJ, 50 Hz, Ø 600 micro m fibre, contact mode, absorber, 1 min; ORA-LASER01 I.S.T.); and (4) combined application - laser/fluoride varnish. Caries-like lesions were created by pH-cycling. After lesion formation, longitudinal sections were taken and examined by polarized light microscopy. RESULTS: In the control group, all samples showed lesions up to 30 micro m in depth. After laser application, lesions could be identified in 15 out of 20 samples. Topical fluoride treatment in groups 2 (varnish) and 4 (laser/varnish) completely inhibited the development of caries-like lesions in all samples. CONCLUSION: In this in vitro investigation, topical fluoride treatment enhances the resistance of sound enamel of primary teeth more effectively than diode laser application.

Chi-Square Distribution↗
PubMed1982

Labelled-replica techniques: post-shadow labelling of intramembrane particles in freeze-fracture replicas.

Three methods are described for direct post-fracture, post-shadow labelling of individual classes of intramembrane particles (IMPs) in freeze-fracture replicas of biological membranes. The P-face IMPs corresponding to the acetylcholine receptor complexes (AChRs) of vertebrate neuroeffector junctions are identified by post-replication labelling with ferritin-antibody complexes and with neurotoxin-biotin-avidin-colloidal gold affinity ligands. (The freeze-etch nomenclature of Branton et al., 1975, is used in this report.) These post-shadow labelling techniques resemble conventional en bloc labelling techniques except that the labelling reagents must penetrate a thin but discontinuous layer of platinum superimposed on the molecules of interest. In the 'sectioned labelled-replica technique', the replicated and labelled tissues are stained, embedded in plastic and sectioned parallel to the replica-tissue interfaces. In the direct 'labelled-replica techniques', the replicated and labelled samples are freeze-dried or critical point dried, the labelled surfaces are stabilized by carbon coating, and the underlying tissues are dissolved, allowing the labelled-replicas to be examined as conventional freeze-fracture replicas. The unshadowed side of each AChR IMP is shown to retain sufficient biochemical information to permit both immunospecific and neurotoxin specific labelling despite formaldehyde fixation, freezing, fracturing, platinum shadowing, and thawing in aqueous media. A new mixed ferricyanide-osmium staining method reveals electron opaque structures spanning the membrane bilayer in the same size, number and distribution as the labelled IMPs. These experiments demonstrate the feasibility of identifying individual IMPs in freeze-fracture replicas and may allow the identification of specific membrane lesions in human disease.

Animals↗
PubMed1991

Cryoultramicrotomy of muscle: improved preservation and resolution of muscle ultrastructure using negatively stained ultrathin cryosections.

Ultrathin sections of rapidly frozen, briefly pre-treated muscle tissue are cut and thereafter are thawed and contrasted using a negative staining technique. The method has provided micrographs in which the in-vivo order in the muscle fibres has been preserved well enough to enable both a more complete interpretation of X-ray diffraction evidence from muscle, and also a gain of new ultrastructural information on aspects of myofibril and myofilament architecture in different types of fibre. Examples here are taken from chicken, rabbit and fish muscles and show both the M-band and the bridge region of the A-band in great detail. To enhance the detail in the original images, one-dimensional (1-D) and 2-D averaging techniques (lateral smearing and step averaging, respectively) are used. Although there is major shrinkage in section thickness to about one-third of its original value, demonstrated here for the first time is the fact that the characteristic A-band lattice planes are preserved in these sections in 3-D. This confirms the usefulness of cryosections not just for 1-D and 2-D image processing, but also for 3-D reconstruction. Thus, in combination with techniques of image processing, cryoultramicrotomy can give the muscle morphologist the detailed data that are needed to match the molecular biologists, biochemists and immunologists in the interpretation of their data about physiological and pathophysiological events in muscle fibres at the macromolecular level.

Animals↗
PubMed2005

The sow endosalpinx at different stages of the oestrous cycle and at anoestrus: studies on morphological changes and infiltration by cells of the immune system.

The aim of this study was to investigate the morphological changes of the sow endosalpinx and the distribution of leukocytes throughout the oestrous cycle and at anoestrus. Nineteen crossbred sows (Swedish Landrace x Swedish Yorkshire) at late dioestrus (three), prooestrus (three), oestrus (three), early dioestrus (three), dioestrus (three) and anoestrus (four) were used. Oviductal samples from three different parts (isthmus, ampulla and infundibulum), taken immediately after slaughter, were fixed, embedded in plastic resin and stained with toluidine blue or stored in a freezer at -70 degrees C until analysed by immunohistochemistry (prooestrus and anoestrus) with an avidin-biotin peroxidase method. Quantitative and qualitative examinations of oviductal epithelium and subepithelial connective tissue were performed by light microscopy. During all stages, a lower degree of morphological changes (pseudostratification, mitosis and secretory granules) was found in the isthmus compared with ampulla and infundibulum. In ampulla and infundibulum, pseudostratification, mitotic activity and secretory granules of the epithelium were high at prooestrus/oestrus. Cytoplasmic protrusions of epithelial cells with some extruded nuclei were prominent in ampulla and infundibulum at all stages except for oestrus and early dioestrus. Lymphocytes as well as CD2- and CD3-positive cells were the predominant immune cells in the epithelial layer. The numbers of lymphocytes and CD3-positive cells did not differ among segments and stages. Numbers of CD2-positive cells did not differ between prooestrus and anoestrus while the numbers were significantly higher in the infundibulum than in ampulla and isthmus. Neutrophils were only occasionally found and mainly in the infundibulum. In the subepithelial connective tissue layer, the two most commonly observed immune cell types were lymphocytes and plasma cells. The numbers of lymphocytes as well as CD2- and CD3-positive cells was lower in isthmus than in the other segments (p < or = 0.001). Higher numbers of plasma cells (p < or = 0.001) were found in infundibulum than in ampulla and isthmus. The numbers of lymphocytes and plasma cells were not significantly different between stages of the oestrous cycle. However, the number of neutrophils differed and were highest at prooestrus in ampulla and infundibulum. The numbers of CD2-, CD3- and CD79-positive cells did not differ between prooestrus and anoestrus whereas for CD14- and SWC3-positive cells, the numbers were higher at prooestrus (p < or = 0.05) than at anoestrus. In the oviduct, the morphology differed in ampulla and infundibulum with oestrous cycle stages, which indicates an effect by ovarian steroid hormones. The immune cell infiltration was less influenced by cyclic changes. However, the immune cell infiltration (in the connective tissue) in the upper part, especially infundibulum, differed significantly from the one in the lower part, isthmus, indicating different immune functions within various parts of the oviduct.

Animals↗
PubMed2006

The endometrium of the anoestrous female pig: studies on infiltration by cells of the immune system.

The aim of this study was to investigate the distribution of immune cells in the endometrium of anoestrous female pigs, five sows in anoestrus by lactation and five pre-pubertal gilts (Swedish Landrace x Swedish Yorkshire). Uterine samples, taken immediately after slaughter, were fixed, embedded in plastic resin and stained with toluidine blue or cryo fixed and stored in a freezer at -70 degrees C until analysed by immunohistochemistry with an avidin-biotin peroxidase method. Immune cells in the surface (luminal) and the glandular epithelium as well as the subepithelial and the glandular connective tissue layers were counted using light microscopy. In the surface (luminal) and the glandular epithelia of gilts and sows, lymphocytes were the predominant immune cells found. There were no significant differences between gilts and sows. Macrophages were detected in the glandular epithelium of sows but not in gilts. In the subepithelial and the glandular connective tissue layers of both gilts and sows, lymphocytes were also the most common immune cells found. The numbers of lymphocytes and macrophages were significantly higher in the sows than in the gilts (p <or= 0.05) in both the layers of connective tissue. Numbers of plasma cells, mast cells, eosinophils and neutrophils in the connective tissue were low and not significantly different between sows and gilts. In both the surface (luminal) epithelium and the subepithelial connective tissue, higher numbers of CD2 than CD3 positive cells were found (p <or= 0.01). The numbers of CD2 positive cells in both epithelium and connective tissue and the number of CD3 positive cells in the epithelium were significantly higher in the sows than the gilts (p <or= 0.05). A few CD79 positive cells were found in the subepithelial connective tissue and none in the epithelia. A few CD14 and SWC3 positive cells were found in the epithelia. The numbers of CD14, SWC3 and MHC class II positive cells were significantly higher in the sows than in the gilts (p <or= 0.05) in the subepithelial connective tissue. In conclusion, the distribution of immune cells in the endometrium of anoestrous female pigs was affected by experienced pregnancy and parturition. In sows with lactation-induced anoestrus, there was a markedly higher cell infiltration (lymphocytes and macrophages) than in the pre-pubertal gilts. In pre-pubertal gilts, lymphocytes dominated, which indicates a role in the maturation of the endometrium.

Aging↗
PubMed2006

The influence of pre- and post-ovulatory insemination and early pregnancy on the infiltration by cells of the immune system in the sow oviduct.

The aim of this study was to investigate the influence of pre- and post-ovulatory insemination and early pregnancy on the distribution of immune cells in the oviduct. Eighteen sows were pre-ovulatory and sixteen sows were post-ovulatory inseminated and slaughtered at different times, 5-6 h after insemination, 20-25 h and approximately 70 h after ovulation, day 11 and day 19. Immediately after slaughter, oviductal samples of three different segments (isthmus, ampulla and infundibulum) were fixed, embedded in plastic resin and stained with toluidine blue or cryofixed and stored in a freezer at -70 degrees C until analysed by immunohistochemistry (pre-ovulatory inseminated sows) with an avidin-biotin peroxidase method. Quantitative and qualitative examinations of oviductal epithelium and subepithelial connective tissue were performed by light microscopy. After pre- or post-ovulatory insemination, neutrophils were not observed in the oviductal epithelium from any of the segments or groups. The numbers of intraepithelial lymphocytes of all sows as well as CD2- and CD3-positive cells of the pre-ovulatory inseminated sows were higher in the infundibulum than in the other segments (p < or = 0.001). In the subepithelial connective tissue of the pre-ovulatory inseminated sows, significantly higher numbers of lymphocytes (p < or = 0.001) and plasma cells (p < or = 0.001) were found in infundibulum than in isthmus. Neutrophils were found mainly in infundibulum, the number approximately 40 h after pre-ovulatory insemination was significantly higher (p < or = 0.05) than in the other groups and segments. Significantly higher numbers of CD2 than CD3-positive cells were found for all groups and segments. In the subepithelial connective tissue of post-ovulatory inseminated sows, the numbers of lymphocytes was higher (p < or = 0.001) at day 19 than up to 50 h after insemination and lower (p < or = 0.001) in isthmus than in ampulla and infundibulum. Neutrophils were found in infundibulum in almost all groups and the number was significantly higher (p < or = 0.05) in the infundibulum up to 50 h after insemination than in other segments. In the oviductal epithelium, no influence of insemination was found on the presence of phagocytes, i.e. neutrophils and macrophages, but on lymphocytes. In the infundibular connective tissue, pre-ovulatory insemination had an effect on neutrophil distribution, indicating an active immune response to insemination in the upper segment. Post-ovulatory insemination changed the oviductal immune cell pattern.

Animals↗
PubMed2006

Bodyworlds and the ethics of using human remains: a preliminary discussion.

Accepting the claim that the living have some moral duties with regard to dead bodies, this paper explores those duties and how they bear on the popular travelling exhibition Bodyworlds. I argue that the concept of informed consent presupposes substantial duties to the dead, namely duties that reckon with the meaning of the act in question. An attitude of respect and not regarding human remains as mere raw material are non-alienable substantial duties. I found the ethos of Bodyworlds premature but full of promises such as public attitudes to organ donations. At the practical level I conclude that Bodyworlds should use only willed donations or unclaimed bodies for which dignified funerals are not available. In the case of live donations, Bodyworlds has a duty to participate in the medical care of needy donors. However, secrecy with regard to the source of cadavers seems to be the most troublesome aspect of Bodyworlds.

Anatomy, Artistic↗
PubMed2005

Different working memory capacity in normal young adults for visual and tactile letter recognition task.

Thirty-nine young adult participants performing the visual and tactile n-back working memory task were compared. In the visual task, letters were presented on a computer screen and in the tactile task, plastic letters embedded on a board were explored tactually. The amount of incorrect responses increased with increasing memory load in both tasks, but was significantly lower in the visual task. Subgrouping the participants with extreme performances into "skilled" and "poor" performers showed that the best performance was found among "skilled" visual performers, and the worst one among "poor" tactile performers. There was more interindividual variation among tactile than visual performance. We conclude that tactile working memory capacity, measured here by letter recognition and letter memory, is generally more limited and shows more variability than visual memory in normal sighted participants.

Adolescent↗
PubMed2005

The sectional anatomy of the carpal tunnel and its related neurovascular structures studied by using plastination.

The aim of this study was to evaluate the morphology of the carpal tunnel and its related neurovascular structures. A slice anatomy study was performed on 12 right wrists of unfixed human cadavers by using the plastination technique. The measurements were performed at the level of the pisiform, hook of the hamate and in the middle between these structures. The diameters of the carpal tunnel and the median nerve were measured at the level of the hook of the hamate. The median nerve can be predicted to be 18 +/- 1.6 mm radial to the pisiform and the ulnar neurovascular bundle 6.8 +/- 1.4 mm radial to the pisiform. Between those structures there will be at least a 9-mm area, localized 8 mm radial to the pisiform, where the incision of the transverse carpal ligament could be performed risk-free. At the hamate hook the median nerve can be predicted at 9.24 +/- 1.18 mm and the ulnar artery lies usually 1.26 +/- 2.5 mm radial to the hook. An understanding of the contents and their positions, and relationships to each other allows an accurate identification of neurovascular structures in the carpal tunnel. Our findings can be used as anatomic landmarks of the carpal tunnel and could be helpful to physicians performing carpal tunnel investigations.

Aged↗
PubMed2000

Microcomputed tomography of kidneys following chronic bile duct ligation.

BACKGROUND: In hepatic cirrhosis, renal sodium and water retention can occur prior to decreases in renal blood flow (RBF). This may be explained in part by redistribution of the intrarenal microcirculation toward the juxtamedullary nephrons. To appreciate this three-dimensional spatial redistribution better, we examined the intrarenal microcirculatory changes using microcomputed tomography (micro-CT) in rats subjected to chronic bile duct ligation (CBDL). METHODS: Six kidneys from control rats and eight kidneys from rats that had undergone CBDL for 21 days were perfusion fixed in situ at physiological pressure, perfused with silicon-based Microfil containing lead chromate, embedded in plastic, and scanned by micro-CT. The microvasculature in the reconstructed three-dimensional renal images was studied using computerized image-analysis techniques. To determine the physiological condition of the rats, parallel experiments were conducted on six control and six CBDL rats to measure mean arterial pressure (MAP), RBF, glomerular filtration rate (GFR), urine flow (UF) rate, and sodium excretion by conventional methods. RESULTS: The percentage of vasculature in the renal cortex from CBDL rats was significantly decreased (10.8 +/- 0.4% vs. 16.8 +/- 2.7% control values). However, the vascular volume fractions of the medullary tissues were not significantly altered. There were no significant differences in the number of glomeruli between groups (36,430 +/- 1908 CBDLs, 36,609 +/- 3167 controls). The CBDL rats had a similar GFR than the controls but a reduced MAP, RBF, UF, and sodium excretion. CONCLUSIONS: The results indicate that after CBDL, there is a selective decrease in cortical vascular filling, which may contribute to the salt and water retention that accompanies cirrhosis.

Animals↗
PubMed2001

The effect of dental implant spacing on peri-implant bone using the rabbit (Oryctolagus cuniculus) tibia model.

PURPOSE: This study investigated the effects of implant proximity on inter-implant bone height, density, and osseointegration using digital radiography and histology. MATERIALS AND METHODS: After a feasibility study, a total of 80 endosteal implants were placed in 20 New Zealand White Rabbit tibias. With the aid of a surgical jig, four 8.5-mm implants were placed in the medial aspect of the tibial crest at inter-implant distances of approximately 1, 1.5, and 3 mm. Standardized digital radiographs using a paralleling device were made immediately after placement of implants. Implants were allowed to osseointegrate for 90 days. After this healing period, the animals were sacrificed, and the standardized radiographs were repeated. The tibias were harvested, processed, and invested in epoxy. Sagittal sections were made from each specimen for histologic evaluation. The initial and postmortem digital radiographs were evaluated for inter-implant distances, vertical bone height changes over time and between implant pairs, and bone density changes over time and between implant pairs using a computer image analysis program and computer statistics program. RESULTS: The actual inter-implant distances were consistent in a range of 0.2 mm. Bone height increased significantly from presurgical levels at all 3 locations (p < .0005). Repeated measures analysis of variance comparing change in bone height at the 3 implant pair distances showed significant differences among the 3 (p = .002). Paired t tests showed that the amount of bone growth at the 1-mm separation site was significantly greater than the 1.5-mm site (p = .026) and the 3-mm site (p = .001), whereas bone growth at the 1.5- and 3-mm sites did not show significant differences (p = .162). A repeated measures analysis of variance comparing change in bone density showed no significant differences (p > .05) among the 3 inter-implant distances for either the 8-mm position (approximately crestal bone height) or the 6-mm position (approximately 2 mm subcrestal). CONCLUSION: Within the limits of this study, it seems placing implants closely together does not adversely affect bone height or density. Conversely, it seems that placing implants closer together may increase bone growth.

Analysis of Variance↗
PubMed2001

Soil bacteria Pseudomonas putida and Alcaligenes xylosoxidans subsp. denitrificans inactivate triclosan in liquid and solid substrates.

Triclosan is a broad-spectrum antimicrobial agent that has been incorporated into many household and medical products. Bacteria with high levels of triclosan resistance were isolated from compost, water, and soil samples. Two of these bacteria, Pseudomonas putida TriRY and Alcaligenes xylosoxidans subsp. denitrificans TR1, were able to use triclosan as a sole carbon source and clear particulate triclosan from agar. A decrease in triclosan concentration was measured by HPLC within 6 h of inoculation with strain TriRY and 24 h with strain TR1. Bioassays demonstrated that triclosan was inactivated in liquid cultures and/or embedded in plastic by the growth of strain TriRY and strain TR1, permitting the growth of triclosan-sensitive bacteria.

Alcaligenes↗
PubMed1997

New cementum formation induced by cyclosporin A: a histological, ultrastructural and histomorphometric study in the rat.

Cyclosporin A (CsA), a widely used immunosuppressive agent, is known to induce gingival overgrowth; 30 mg/kg/d of CsA were administrated orally in young and adult male Sprague-Dawley rats. The same number of rats received oil-based vehicle solution. After 4, 9, 14 and 19 wk of CsA or vehicle administration 3 control and 3 experimental rats were anaesthetized and tissues fixed by an intracardiac perfusion of fixative solution. Upper and lower jaws were dissected, demineralized and processed for Epon inclusion. Histological examination revealed the presence of large amounts of new cementum (NC) covering extensive areas of the acellular extrinsic fibre cementum (AEFC) in all the root surfaces. NC was particularly abundant at the cervical third of the roots facing the gingival connective tissue, where it occurred as layers, spurs or in both configurations. NC was characterized by its irregular outline, globular body content and infrequent presence of incremental lines. Histomorphometric evaluation by semi-automatic image analysis indicated that the volume and the external surface of NC spurs were 2.86-6.49 and 1.29-1.97-fold increased comparative to those of the AEFC covering the same root areas. Electron microscopy revealed that NC was a functional tissue with insertion of collagen fibres perpendicularly to the long axis of the root. It can be concluded that under some experimental conditions formation of abundant amounts of NC can be achieved and that these results must be taken into account for a new approach in the treatment of periodontal disease.

Administration, Oral↗
PubMed1997

Maintenance of new cementum formed during cyclosporin A administration after suspension of the treatment.

The aim of the present investigation was to examine if new cementum (NC) formed during cyclosporin A (CsA) administration was maintained after suspension of the treatment. Thirty mg/kg/d of CsA were given to 3 male Sprague-Dawley rats. Three control rats received oil-based vehicle solution. Nine wk later the drug and vehicle administration were stopped and the rats continued to be fed with the same standard laboratory diet and water ad libitum for 5 months. The rats were anaesthetized, the tissues fixed by intracardiac perfusion of fixative solution and the mandibles processed for Epon inclusion. Histological, histomorphometric and ultrastructural analysis revealed that (a) NC covered extensive areas of the root surfaces; its structural characteristics were identical to those observed in the rats killed during CsA administration. (b) collagen fibres of the adjacent connective tissue were functionally inserted into the NC. (c) In the presence of cervical NC spurs the extent of the apical downgrowth of the junctional epithelium, measured parallel to the cemento-dentinal junction, was decreased (up to 64%) compared to the one occurring in areas devoid of NC deposits. These results suggest that (a) NC deposition and its functional relations with the adjacent connective tissue are not reversible after cessation of CsA treatment and (b) in the presence of cervical NC spurs the amount of connective tissue attachment on the root surfaces is increased.

Animals↗
PubMed1979

Mechanical properties and hydroxyproline content of connective tissue in porous ceramic implants.

The present study describes a model applying ceramic implants (A1203) for in vivo studies of connective tissue regeneration. Two types of implants have been developed: a one-piece model for histological examination and chemical analyses, and a two-piece implant which can also be used for mechanical testing of connective tissue. When these were implanted subcutaneoulsly on the back of rats, a correlation was found between the mechanical strength and the hydroxyproline content of connective tissue in the implants. The peak synthesis occurred between the 7th and the 14th day after implantation, and a plateau was reached for both strength-increases and hydroxyproline-formation between the 14th and the 21st days. For histological examination, the implants were embedded in plastic materials and prepared as hard tissue specimens. The model presented can be applied to study connective tissue regeneration in normal and pathological conditions, including studies of the effects of various drugs on the connective tissue.

Aluminum Oxide↗