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Biomedical subjects

R Bergman

Publications and source records attributed to R Bergman.

At least 73 records · Page 4Linked to original sources
PubMed1999

Immunohistopathologic diagnosis of epidermolysis bullosa.

Routine histologic study usually is insufficient to subclassify epidermolysis bullosa (EB); currently, electron microscopic evaluation has been the gold standard. A major advance recently has been made in elucidating the molecular basis of several major forms of EB. Concomitantly, immunoreagents have been developed to map antigens in the basement membrane zone. Some of these reagents facilitate the classification of EB into types and subtypes and can be used as an adjunct informative screening procedure to direct mutation identification efforts using DNA technologies. The current review provides an overview of these recent developments and a more detailed account of the immunohistopathologic diagnosis of EB.

Autoantigens↗
PubMed1999

How useful are T-cell receptor gene rearrangement studies as an adjunct to the histopathologic diagnosis of mycosis fungoides?

The diagnosis and differential diagnosis of mycosis fungoides (MF) is often difficult, clinically and histologically. Recent attempts to enhance diagnostic sensitivity have involved T-cell receptor (TCR) gene rearrangement studies, using Southern blot or polymerase chain reaction (PCR) technique. PCR is more widely used because of its increased sensitivity, lower labor- and cost-intensive analytic steps, lack of radioactive substances, and applicability to routinely processed biopsies. Several studies that use this technique detect clonal bands in 50% to 83% of the MF specimens from patch, patch/plaque, and erythrodermic stages, which often pose a diagnostic challenge. This compares with no clonality in the control groups of most of these studies, or with up to 13% in a few studies, although long-term follow-up reveal that some cases of so-called "clonal dermatitis" eventually progress into overt cutaneous T-cell lymphoma. Furthermore, retrospective studies on archival histologic material from patients with MF demonstrate similar rates of clonality in histologically "inconclusive," "borderline," and diagnostic MF biopsies. Therefore, in the proper clinicopathologic setting, and with consideration of the known limitations of this technique, TCR gene rearrangement studies on lesional skin using PCR may be helpful as an adjunct to the histopathologic diagnosis of MF.

Diagnosis, Differential↗
PubMed1999

Apoptosis, Fas and Fas-ligand expression in melanocytic tumors.

Impaired regulation of apoptosis is known to be associated with the development of various forms of cancer. Fas binding to its ligand, Fas ligand (Fas-L), has been shown to trigger apoptosis in various cell types. Fas-L is expressed by melanoma cells and has been suggested to play a role in melanoma escape from immune surveillance. In the present study, we assessed apoptotic activity and examined Fas and Fas-L expression in malignant melanomas, Spitz nevi and ordinary melanocytic nevi. We evaluated apoptotic activity using terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick end labeling. Apoptotic activity was found to be minimal in melanomas and moderate in Spitz nevi. In contrast, common nevi demonstrated significant levels of apoptosis in the deep parts of the tumor. Fas was found to be expressed by all Spitz nevi, most melanocytic nevi and approximately half of the malignant melanoma specimens. Fas expression was also significantly more pronounced in Spitz nevus cells as compared with the two other tumors. The anti-Fas-L antibody was found to stain all three melanocytic tumors. Staining was shown to be stronger and more frequent in melanoma cells as compared to the nevus cells. Using the Spearman test, no significant correlation between Fas-L expression in melanoma cells and apoptosis in MM-infiltrating mononuclear cells was found, suggesting that Fas-L expression in melanoma cells may not be instrumental in their ability to escape immune mechanisms of defense. In contrast, increased levels of apoptosis in the deep parts of melanocytic nevi may reflect and possibly contribute to their benign nature.

Apoptosis↗
PubMed1999

Sexuality among institutionalized elderly patients with dementia.

The subject of sexuality among elderly patients with dementia was examined, focusing on two main aspects: the sexual behaviour of institutionalized elderly people with dementia; and the reactions of other patients, staff and family members to this behaviour. The behaviour was found to be mostly heterosexual and ranged from love and caring to romance and outright eroticism. Reactions varied, being accepting of love and care but often objecting to erotic behaviour. Understanding of the sexual needs of elderly people should become an integral part of the training and continued education of health care staff, thus helping to resolve conflicts and clarify common misconceptions.

Aged↗
PubMed1998

Atrichia with papular lesions maps to 8p in the region containing the human hairless gene.

Atrichia with papular lesions (APL) (OMIM 209500) is a hereditary form of alopecia. Hair loss occurs soon after birth and is followed years later by the development of a diffuse papular eruption. Its mode of transmission is still uncertain. A related but clinically distinct form of alopecia, known as alopecia universalis (OMIM 203655), has recently been found to be associated with a mutation in the human hairless gene. The present report describes the largest consanguineous kindred of APL reported to date and provides strong evidence for autosomal recessive inheritance of this rare disorder. On the basis of a linkage analysis of this kindred using six microsatellite markers spanning the human hairless gene region, we found that the APL locus maps to chromosome region 8p12 in a 5 cM interval between marker D8S560 and marker D8S1739. A maximum lodscore of 3.7 was obtained with marker D8S1786, at a recombination fraction of 0. Our results suggest phenotypic variability at the hairless locus although they do not rule out the existence of a gene cluster associated with hair disorders in the same region.

Alopecia↗
PubMed1998

Reduced folate carrier (RFC-1) gene expression in normal and psoriatic skin.

Methotrexate is widely used in the treatment of severe psoriasis. However, little is currently known about the mechanisms underlying its therapeutic activity in the skin. Methotrexate has been shown to be carried into cells through the reduced folate carrier (RFC-1). The recent cloning and characterization of the human gene encoding this transmembranal carrier enabled us to investigate RFC-1 gene expression in human skin. Biopsies were obtained from the skin of healthy and psoriatic volunteers. RNA extracted from these biopsies was analyzed by the reverse transcriptase-polymerase chain reaction technique. While RFC-1 gene expression was barely detectable in the uninvolved skin of psoriatic patients and in the skin of healthy volunteers, high levels of RFC-1 transcripts were found in biopsies obtained from psoriatic plaques. To further investigate this pattern of gene expression, we studied skin biopsies by in situ hybridization with a labeled antisense riboprobe specific for the RFC-1 gene. The RFC-1 gene was found to be weakly expressed in the epidermis, in biopsies obtained from the skin of healthy subjects as well as in those from the uninvolved skin of psoriatic patients. In contrast, in biopsies obtained from psoriatic plaques, high levels of RFC-1 gene transcripts were found mostly in the spinous layer of the epidermis. These results suggest the existence of a specific methotrexate carrier in the human epidermis, and may bear relevance to the cutaneous manifestations of methotrexate toxicity.

Adult↗
PubMed1998

Immunophenotyping and T-cell receptor gamma gene rearrangement analysis as an adjunct to the histopathologic diagnosis of mycosis fungoides.

BACKGROUND: The histopathologic diagnosis of mycosis fungoides (MF) may be difficult. OBJECTIVE: Our purpose was to evaluate the role of immunophenotyping and T-cell receptor (TCR) gene rearrangement studies as an adjunct to the histopathologic diagnosis of MF. METHODS: Immunohistochemical studies with antibodies to CD4, CD5, CD7, and CD8 and TCR gamma gene rearrangement analysis with a polymerase chain reaction were performed on fresh-frozen material of patients with "classic" histology of MF, "inconclusive" histology, and benign inflammatory dermatoses. RESULTS: Clonal TCR gamma gene rearrangements were found in 11 of 16 (69%) of classic MF cases, in 3 of 19 (16%) of inconclusive cases, and in none of the 12 inflammatory dermatoses cases (P < .05 and P < .001, respectively). Only the mean CD7 counts were statistically significantly different between these 3 groups (MF < inconclusive < inflammatory). CONCLUSION: Inconclusive histology is probably a heterogeneous group in which CD7 counts and TCR gamma gene rearrangement studies might help to differentiate the MF cases from the benign cases.

Adolescent↗
PubMed1998

Ability of alternative indices of insulin sensitivity to predict cardiovascular risk: comparison with the "minimal model". Insulin Resistance Atherosclerosis Study (IRAS) Investigators.

INTRODUCTION: Although recognition of insulin sensitivity as a risk factor for cardiovascular disease is growing, a deeper understanding of its role is impeded by the cost and complexity of currently available measures. This report evaluates previously described alternative indices of insulin sensitivity with the goal of identifying a reliable, but logistically simpler, alternative. METHODS: Data from 1460 participants in the Insulin Resistance Atherosclerosis Study (IRAS) were used to assess the proportion of the relationship between a recognized measure of insulin sensitivity (Bergman's SI) and cardiovascular risk factors that is contained in each of nine alternative measures. RESULTS: A number of the alternative indices contained a substantial proportion of the information available in Bergman's SI. The Galvin's index and the homeostasis model were most promising. However, there remained a significant amount of the information in Bergman's SI that was not contained in any of the alternative indices. DISCUSSION: There are simpler alternative indices of insulin sensitivity for use in epidemiological studies, but each alternative is associated with some loss of information. It may be possible that this loss can be overcome with an increased sample size; however, using the alternative indices may also confound the assessment of insulin sensitivity with other underlying factors (i.e., hyperinsulinemia). The alternative indices are not recommended for the clinical assessment of insulin sensitivity for an individual patient or subject.

Cardiovascular Diseases↗
PubMed1998

Diabetic dermopathy and internal complications in diabetes mellitus.

BACKGROUND: Diabetic dermopathy is the most common cutaneous marker of diabetes mellitus. The relationship of diabetic dermopathy to internal complications of diabetes mellitus, such as nephropathy, retinopathy, and neuropathy, is still unknown. METHODS: The possible role of diabetic dermopathy as a clinical sign of internal complications in diabetes mellitus was investigated. One hundred and seventy-three patients with diabetes mellitus, of whom 125 (72%) had insulin-dependent diabetes mellitus and 48 (28%) had non-insulin-dependent diabetes mellitus, were studied. RESULTS: Diabetic dermopathy was present in 69 (40%) of patients, statistically more significant in patients 50 years of age and older. The mean diabetic duration was significantly higher in patients with diabetic dermopathy than in those without. The associations of diabetic dermopathy with retinopathy, nephropathy, and neuropathy were each statistically significant, and the increased frequency of diabetic dermopathy correlated with an increased number of these three complications in each patient. CONCLUSIONS: Some of the factors that affect the development of internal complications in diabetes mellitus may play a role in the development of diabetic dermopathy, and diabetic dermopathy may serve as a clinical sign of an increased likelihood of these internal complications in diabetic patients.

Adolescent↗
PubMed1998

C-fos protein expression in Spitz nevi, common melanocytic nevi, and malignant melanomas.

The expression of c-fos protein was studied in formalin-fixed, paraffin-embedded sections of 11 compound Spitz nevi (SNs), 16 ordinary compound melanocytic nevi (MNs), and 17 malignant melanomas (MMs) using monoclonal antibody MAB1283 and an immunoperoxidase technique. Eleven (100%) SNs, 15 (94%) MNs, and 16 (94%) MMs showed positive reactions in some of the tumor cells (p = nonsignificant). In the majority of the tumors the staining was located in nuclei and graded as moderate to strong in intensity. The percentages of positively stained cells did not differentiate the three types of tumor, although they were higher in the melanocytic nevi. Most of the lesions with a significant dermal component did not show stratification of staining with progressive descent into the dermis. Positive staining for c-fos was also frequently found in the normal skin constituents within and adjacent to the melanocytic tumors. In conclusion, the pattern of expression of c-fos in routinely processed specimens does not differentiate between SNs, MNs, and MMs.

Cell Nucleus↗
PubMed1998

Peeling skin syndrome with hair changes.

A 13-year-old boy with typical peeling skin syndrome (PSS) is described. The clinical picture corresponded to the inflammatory variant of PSS (type B). In addition, the patient had gross and microscopic hair anomalies such as trichorrhexis invaginata-like changes, irregular hair shaft torsions and moniliform hair shaft diameter reductions. The observed dysmorphic hair changes are discussed and interpreted as being an integral component of the dermatosis in this case. To the best of our knowledge, such hair anomalies have not yet been described in PSS.

Adolescent↗