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Biomedical subjects

R Nilsen

Publications and source records attributed to R Nilsen.

At least 55 records · Page 3Linked to original sources
PubMed1994

Microbial associations of 4 putative periodontal pathogens in Sudanese adult periodontitis patients determined by DNA probe analysis.

The few previous cultivation studies on the in vivo associations between various periodontal microbial species have shown several positive and negative associations. The present investigation utilized DNA probe analysis to examine possible in vivo associations between the periodontal pathogens Porphyromonas gingivalis, Prevotella intermedia, Fusobacterium nucleatum, and Bacteroides forsythus in subgingival plaque samples obtained from 25 Sudanese untreated adult periodontitis patients. The standard paper point technique was used to sample 99 sites with a mean probing depth of 6.8 mm (range 6.0 to 10.0). Microbial associations were determined by detecting the effect of the presence or absence of one species (effector) on the occurrence of the other 3 species (target). The Wilcoxon signed rank test was used to examine variations in occurrence of each target bacteria in the presence or absence of the effector. In addition, the Spearman's rank correlation test was used to assess the relationship between the level of each bacteria to that of the other 3. Results showed bacterial associations with the following effector-on-target effects: F. nucleatum (P < 0.01 Wilcoxon; P < 0.001 Spearman) >> P. gingivalis (P < 0.01 Wilcoxon; P < 0.001 Spearman), and B. forsythus (P < 0.05 Wilcoxon; P < 0.001 Spearman) > P. intermedia (P < 0.01 Spearman). The study demonstrated positive associations between the 4 species investigated, while no neutral or negative associations were revealed. The most striking finding was the effect exerted by F. nucleatum on the colonization of P. intermedia; P. intermedia was never detected in a site unless F. nucleatum was also present.

Adult↗
PubMed1992

In situ characterization of mononuclear cells in marginal periodontitis of patients with Down's syndrome.

An indirect immunofluorescence technique on cryostat sections was used to study the cellular composition in chronic marginal periodontitis (CMP) of patients with Down's syndrome (DS). The findings were compared with CMP lesions in otherwise normal patients (NP). The distribution and amount of CD22+ cells (B lymphocytes), CD3+ cells (pan T lymphocytes), CD4+ cells (helper T subset), CD8+ cells (suppressor/cytotoxic T subset), and CD11c+ cells (in tissue, mainly monocytes and macrophages) were investigated. Morphologic studies showed a denser inflammatory infiltrate in DS than in NP. Countings showed significant differences in cell distribution (p = 0.0003) and cell profiles (p = 0.0273) between the two groups. The median CD4+/CD8+ ratio in DS (2.73) was significantly higher (p = 0.0024) than found in gingival inflammatory lesions from NP (1.08). The present study shows that DS patients have a different, more pronounced, immune response in CMP than NP.

Adult↗
PubMed1991

[Dentistry in developing countries].

The author presents different approaches to dental activities in developing countries. The general prevalence of dental caries and periodontitis in developing countries is low. The limited resources for health programmes, and for oral health in particular, underscore the need to make priorities in order to improve the health of the inhabitants. To promote oral health, it is necessary to focus on improving knowledge about the major oral diseases and the possibility of developing community-based programmes of intervention and prevention. The integration of oral health into general health programmes is a major goal in the prevention and combat of oral diseases. Knowledge and research in fields of oral medicine, preventive oral programmes as well as in fluoride toxicology as part of water programmes is important.

Dental Care↗
PubMed1991

[Testing of a simple information program to improve elderly patients' knowledge about their medication].

The programme, which was provided as a supplement to the standard information on the patient's medication upon discharge from hospital, consisted of oral information about which drugs to use and how to take them, a medication card, and one page of general information on how to take drugs. The programme was tested in an open, controlled manner in 24 test and 23 control patients, mean age 80 years. The results revealed that the patients' knowledge about their medication was generally good at follow-up four weeks later. The test group achieved a significantly higher score on questions about the technique for taking oral medication and why this is important. It is concluded that this type of information should be supplied when elderly patients are discharged from hospital.

Age Factors↗
PubMed1990

[What do health care institutions do to inform the aged and train them in the correct use of drugs?].

We reviewed the routines for providing information on drugs, and for training in the use of drugs and aids to medication in hospital and nursing homes by interviewing 11 ward supervisors. We found that little attention was given to systematic training in the use of drugs, training and aids to medication as part of the patient rehabilitation. All wards informed the patients about the type and dosage of drugs to be taken after discharge. However, printed information from the Norwegian Medicines Control Authority was not used to any significant extent. Lack of time was stated as the major reason for not providing more systematic information and training on drug usage as part of the rehabilitation programme for elderly inpatients.

Aged↗
PubMed1990

The pathogenesis of Leishmania aethiopica infection in BALB/c mice.

A mouse model for L. aethiopica infection is described. BALB/c mice were unable to clear an infection with 1 x 10(7) promastigotes injected into the hind footpad. However, there was no ulceration of the lesion and no development of overt clinical symptoms after 203 days of infection. Spread of viable organisms was evident in the draining lymph node but not in the spleen or liver. The control of the infection was associated with the development of classical delayed hypersensitivity responses to phenolized promastigotes and appeared as a localized granulomtaous infiltration. The infiltration had features of classical tuberculoid granulomas, but superimposed on it was a strong eosinophilic infiltration. The relevance of such cells though unclear is discussed.

Animals↗
PubMed1990

The composition of gingival inflammatory cell infiltrates in children studied by enzyme histochemistry.

Gingival biopsies were obtained from 23 children, aged 5-11 years (8.6 +/- 1.8 years). Specimens were taken from areas of the gingiva adjacent to the teeth which were to be extracted because of caries or its sequelae and which clinically had a gingival index score of at least 1. Staining for alpha-naphthyl acetate esterase with unspecific esterase at pH 5.8 (ANAE) permitted identification of T lymphocytes, monocytes/macrophages, plasma cells and non-reactive (ANAE-negative) cells. Cells which tentatively were identified as "natural killer" (NK) cells were also observed. Differential cell counting was performed for 10 specimens, selected on the basis of the presence of a well-defined inflammatory infiltrate, clear morphology throughout and good ANAE staining. Cell counts confirmed earlier studies showing that lymphocytes predominate in the inflammatory infiltrates in childrens' gingivitis. T lymphocytes dominated particularly in the periphery of the most densely infiltrated areas. Relatively few plasma cells were seen. It was concluded that T lymphocytes dominate in the inflammatory infiltrate in childrens' gingivitis.

Cell Count↗
PubMed1990

Variation in the composition of gingival inflammatory cell infiltrates.

Biopsy specimens were taken at gingivectomy from 18 adult patients undergoing treatment for chronic marginal periodontitis. They were embedded so that the cut surface of the gingiva was parallel to the top of the block to obtain a comprehensive view in a transversal plane of the inflammatory cell infiltrate near the bottom of the pocket. Sections were stained with HES or with toluidine blue for histological description, and acid alpha-naphthyl acetate esterase (ANAE) was used to differentially stain T lymphocytes, plasma cells and monocytes/macrophages. Sections stained with HES showed that the density and size of the cell infiltrates varied along the circumference of a tooth over very short distances and on various surfaces on neighbouring teeth. Differential counts of cells stained for ANAE demonstrated great variation in the composition of the cell infiltrates, particularly along the pocket epithelium. The predominating ANAE positive cell type in this area was T lymphocytes, while in the central connective tissue, plasma cells predominated. There was no systematic covariation between the localization of the gingiva (i.e. mesial, facial, etc.) and the composition of the cell infiltrates. The local variation in the composition of the cellular infiltrate most likely reflects local variability in the noxious substances (i.e. plaque composition) within the periodontal pocket, and in the resulting local inflammatory response.

Adult↗
PubMed1989

In situ localization of interferons in psoriatic lesions.

An indirect immunofluorescence technique, using murine monoclonal antibodies (MoAbs) against human IFN-alpha and human IFN-gamma was used to study IFNs in cryostat sections from psoriatic skin lesions. The IFNs were more pronounced in sections from highly active psoriasis than in sections from stationary psoriasis. In highly active psoriatic lesions IFN-alpha was localized to keratinocytes is stratum basale, to some epidermal dendritic cells, probably Langerhans cells, and to some mononuclear cells in dermis. IFN-alpha was usually not detected in sections from stationary psoriasis. IFN-gamma was localized to stratum corneum, to keratinocytes around microabcesses and to mononuclear cells in the dermal cell infiltrates, predominantly in highly active psoriatic lesions. Both IFN-alpha and IFN-gamma were localized to some endothelial cells in the papillary dermis. The MoAbs did not stain sections from unaffected skin from patients with psoriasis or sections from healthy individuals. The findings indicate that the IFN system in the skin may be of significance in the pathophysiology of psoriasis.

Antibodies, Monoclonal↗
PubMed1989

Localization of Fc gamma receptors and complement receptors CR1 on human peripheral nerve fibres by immunoelectron microscopy.

The localization of receptors for the Fc part of IgG (Fc gamma R) and for the complement C3b/C4b components (CR1) on human peripheral nerve fibres was investigated by indirect immunoperoxidase staining of frozen nerve sections with monoclonal antibodies. Transmission electron microscopy revealed that Fc gamma R and CR1 are localized to the entire surface membrane and inner membrane (axolemma) of the Schwann cell. Myelin and axons were not stained. The presence of Fc gamma R and CR1 in human Schwann cells adds further evidence for the immunocompetence of these cells.

Animals↗
PubMed1989

The role of nerve biopsies in the diagnosis and management of leprosy.

Skin and nerve biopsies from 81 patients clinically suspected to have leprosy were studied. Histologically 54% of the patients showed leprosy. Both nerve and skin biopsies were histologically diagnostic of leprosy in 64% of these cases while 32% were diagnostic in the nerve but not skin biopsy. In the 11 patients with multibacillary leprosy (BI greater than or equal to 2) a multibacillary picture was seen in all nerve biopsies while 8 patients exhibited a paucibacillary leprosy of the skin and a multibacillary leprosy in the nerve. The present results emphasize that leprosy is a disease of peripheral nerves and that diagnostic criteria other than skin parameters is important to reach a proper diagnosis. The evident possibility of having patients with a multibacillary leprosy in peripheral nerves and paucibacillary in skin emphasize the need of clinical studies to clarify the criteria for the diagnosis of paucibacillary leprosy and the drug regimen for this group of patients.

Adolescent↗
PubMed1987

In situ characterization of the cutaneous immune response in Ethiopian cutaneous leishmaniasis.

Cryostat sections from 10 patients with localized cutaneous leishmaniasis (LCL) and eight patients with diffuse cutaneous leishmaniasis (DCL) from Ethiopia were studied with immunofluorescence methods for the phenotypic characterization of cells in the lesions. Higher numbers of Leu 2+ and Leu 3+ cells (P less than 0.005) were found in LCL than in DCL, while the Leu 3a + b/Leu 2a ratios were the same. No differences were found in the numbers of transferrin receptor, HLA-DR, and HLA-DQ expressing cells in the granulomas. Significantly (P less than 0.0001) lower numbers of IL-2 receptors expressing (Tac+) cells were found in DCL than LCL lesions, suggesting interference in the activation of the T cells. IL-2-containing cells were absent in DCL and were found in LCL lesions. Epidermal keratinocytes above the LCL but not the DCL lesions expressed HLA-DR (but not HLA-DQ) antigen, suggesting a lower gamma-interferon production in the DCL granulomas. The number of Langerhans' cells (Leu 6+) was higher in the epidermis of DCL (P less than 0.005) than in LCL, while a lower number of Leu 6+ cells were seen in the dermal lesions (P less than 0.001). These observations could account for some of the mechanisms responsible for the disturbed immunostimulation and immunoregulation observed in the lesions of DCL.

Ethiopia↗
PubMed1987

In situ demonstration of Fc gamma-receptors in human chronic marginal and apical periodontitis.

The distribution of receptors for the Fc portion of IgG (Fc gamma R) in chronic marginal and apical periodontitis were studied by using a monoclonal antibody against placental Fc gamma R and soluble immune complexes as indicators. Cryostat sections were used in indirect immunofluorescence technique. Fc gamma R were detected on varying numbers of cells in the inflammatory cell infiltrates, on endothelial cells of certain vessels and in fibrous tissue. In chronic marginal periodontitis Fc gamma R were also observed on cells within the oral gingival epithelium (OGE) and the pocket epithelium (PE). There was a distinct fluorescence in stratum spinosum and occasionally in stratum basale of OGE and in the coronal portion of the PE. Fc gamma R on Langerhans cells could not be demonstrated. In apical periodontitis Fc gamma R were also detected on cells within the epithelium. In some cases epithelium in periapical cysts was positive. Soluble immune complexes bound to morphologically similar, but fewer cells compared to the monoclonal antibody against Fc gamma R. The results indicate that Fc gamma R are generally expressed on cells in inflamed tissue. Thus, this presence of Fc gamma R on certain specialized cells such as endothelial cells and keratinocytes, may endow these cells with functions previously thought to be restricted to cells of the lymphoreticular system.

Adolescent↗
PubMed1986

In situ characterization of the inflammatory cell infiltrates of hyperplastic denture stomatitis.

Cryostat sections from 14 surgical specimens were examined to determine whether selected factors of the immune response related to histopathological reactions are present in the palatal mucosa affected by hyperplastic denture stomatitis. By means of various immunological techniques the presence of IgG, IgA, IgM, complement factor C3c, receptors for the Fc region of IgG (FcR) and for complement factor C3b (C3bR), T lymphocytes, and macrophages were studied. The inflammatory infiltrate was mainly located in the papillary part of the lamina propria. IgG, IgA, and IgM appeared both in plasma cells and intercellularly. FcR, C3bR, and T lymphocytes were present in the areas with inflammatory cell infiltrate. Macrophages were found in the papillary part of the lamina propria and within the epithelium. The immunological response in the mucosa affected by denture stomatitis was in many respects similar to that of marginal and apical periodontitis. We conclude that hyperplastic denture stomatitis is a complex inflammatory lesion showing elements of both humoral and cellular immune responses.

Antibody Formation↗
PubMed1985

Complications that may occur in those with spinal cord injuries who participate in sport.

The purpose of this study was to determine the risk of developing complications in paraplegics taking part in sport. It is a retrospective study of patients with complete spinal cord injury at the spinal level of C7--cauda equina/conus injury, and consists of 61 patients admitted to the Beitostølen Healthsportcenter, Norway. All of them had achieved satisfactory bladder/bowel function. The wheelchair dependents were all skilled in the use of the wheelchair. They participated in a training programme with an average duration of 25 days. Different activities were tried, such as weight-lifting, pulking, swimming, volleyball, calisthenics in a group, horseback-riding, archery, tabletennis, canoeing, totalling 11 955 training hours. During the training period the following complications were observed: urinary tract infections, pressure sores, and sprains and strains. There were 30 complications, most of them only of minor type. The incidence of complications, expressed as number of complications/1000 training-hours was, for urinary tract infections--0,50, pressure sores 0,42, sprains/strains 1,33, others 0,25: in all 2,51. Sprains and strains were the most common complications, accounting for about 55 per cent of the total, all of which were successfully treated before discharge. Sport activities are an important part of the rehabilitation of the spinal cord injured and the risk of serious complications appears to be low.

Athletic Injuries↗