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Biomedical subjects

R Bergman

Publications and source records attributed to R Bergman.

At least 37 records · Page 2Linked to original sources
PubMed2004

Deleterious mutations in SPINK5 in a patient with congenital ichthyosiform erythroderma: molecular testing as a helpful diagnostic tool for Netherton syndrome.

The congenital erythrodermas represent a heterogeneous group of inherited and acquired disorders often accompanied by systemic infections, impaired epidermal barrier function and concomitant life-threatening fluid and electrolyte imbalance. In the present report, we describe a patient who was considered to have congenital ichthyosiform erythroderma for 26 years until molecular testing led to the correct diagnosis of Netherton syndrome.

Adult↗
PubMed2003

Dielectric relaxation studies of poly(propylene glycol) confined in vermiculite clay.

The molecular dynamics of oligomeric poly(propylene glycol) (PPG) liquids (M(w)=1200, 2000 and 4000 g/mol) confined in a two-dimensional layer-structured Na-vermiculite clay has been studied by broadband dielectric spectroscopy. In addition to the alpha-relaxation, the normal mode relaxation process was studied for all samples both in bulk and confinement. For the normal mode process the relaxation rate in the clay is drastically shifted to lower frequencies compared to that of the bulk material in contrast to the alpha-process whose relaxation time is only slightly affected by the confinement. Also the temperature dependence of the relaxation time for the normal mode process is strongly affected by the confinement. Moreover, in the clay the intensity of the normal mode is stronger than that of the alpha-process, in contrast to the bulk samples where the opposite is observed.

Journal Article↗
PubMed2003

Chain-length-dependent relaxation scenarios in an oligomeric glass-forming system: from merged to well-separated alpha and beta loss peaks.

We have studied the relaxation dynamics of a homologous series of propylene glycol based dimethyl ethers in the supercooled regime by means of broadband dielectric spectroscopy. The system is chosen in order to minimize changes of the intermolecular interactions with varying molecular weight, M. A gradual transformation from a scenario of well-separated to one of merged alpha and beta loss peaks was observed with decreasing M. The results give strong evidence for the currently debated excess wing being due to an underlying beta relaxation. The study suggests that the main difference between glass formers with and without excess wings is the relaxation time at the merging temperature.

Journal Article↗
PubMed2003

Compound heterozygosity for mutations in the hairless gene causes atrichia with papular lesions.

BACKGROUND: Congenital atrichias represent a complex and heterogeneous group of genodermatoses, which have been shown in several consanguineous families to result from homozygous mutations in the hairless gene (HR). OBJECTIVES: To identify the molecular basis of congenital atrichia in a non-consanguineous family. METHODS: Genetic analysis was carried out in a two-generation family with two children with congenital atrichia and one healthy child. RESULTS: We established a diagnosis of atrichia with papular lesions based on clinical and histopathological data. We identified a heterozygous 11-bp deletion (189-199del) in the two affected children and their mother. In addition, the two affected children and their father were shown to carry a non sense mutation (Q478X), which has previously been described in a Pakistani family. Haplotype analysis revealed that mutation Q478X occurred independently in the two families. CONCLUSIONS: We have identified the first case of compound heterozygosity for mutations in HR as well as the first instance of a recurrent mutation in this gene. These data further expand our understanding of the molecular pathomechanisms underlying congenital atrichias.

Alopecia↗
PubMed2003

Resolution of orofacial granulomatosis with amalgam removal.

A 61-year-old woman presented with a 2-year history of an abnormal erythematous swelling on the upper lip and cheek. Upon examination there were no other physical findings. Histological examination found discreet sarcoidal granulomas in the lower dermis. Routine laboratory studies, chest radiographs and pulmonary functions were all normal. Clinical presentation and histological findings were, therefore, compatible with the diagnosis of orofacial granulomatosis (OFG). The patient was patch tested with an extended standard series that included metal-salt, dental prosthesis, bakery and corticosteroids series. The patch test was positive (score ++) after 48 and 72 h for mercury in the metal-salt and dental prosthesis series. During the past decade the patient had received amalgam fillings of several dental cavities, including one adjacent to the swollen cheek. The unilateral localization of the soft tissue swelling adjacent to the amalgam tooth fillings, along with the positive patch test for mercury, raised the possibility that the OFG was part of a delayed hypersensitive reaction to the fillings. The patient therefore underwent a total amalgam replacement procedure; complete disappearance of the swelling overlying the right cheek was observed within 7 weeks and the swelling of the upper lip subsided completely within 6 months. We propose that mercury in amalgam tooth fillings is another cause of OFG and suggest appropriate patch testing in patients who do not have an apparent cause of OFG.

Cheek↗
PubMed2003

Alopecia areata and relapsing polychondritis or mosaic autoimmunity? The first experience of co-trimoxazole treatment.

A 13 year old girl presented with auricular chondritis and recurrent episodes of unexplained chest pain, arthritis, bronchitis, conjunctivitis, prolonged steroid resistant alopecia areata, and a history of recurrent tonsillitis. Both the mosaic of autoimmunity and relapsing polychondritis were considered in the differential diagnosis. The patient was successfully treated with co-trimoxazole. The significance of co-trimoxazole, which is an antibiotic and an immunomodulatory drug, in the treatment of autoimmune disease is discussed.

Adolescent↗
PubMed2003

Dynamics of propylene glycol and its oligomers confined in clay.

The dynamics of propylene glycol (PG) and its oligomers 7-PG and PPG, with Mw = 4000 (about 70 monomers), confined in a Na-vermiculite clay have been investigated by quasi-elastic neutron scattering and dielectric spectroscopy. The liquids are confined to a single molecular layer between the clay platelets, thus giving a true 2D liquid. The results show that the average relaxation time [tau], deduced from neutron scattering at a momentum transfer Q of about 1 A(-1) is in perfect agreement with the dielectric alpha-relaxation time, although neutron scattering does not only probe the main (alpha-) relaxation, but all motions of hydrogens on the experimental time scale. At room temperature 1/[tau] is proportional to Q(2), indicating that the relaxations are mainly due to ordinary translational diffusion. The most unexpected finding is that [tau](or the dielectric alpha-relaxation time) is almost unaffected by the 2D confinement, in contrast to the dielectrically active normal mode of PPG which is substantially slower in the confinement. Only the 7-mer has a significantly slower segmental translational diffusion in the clay. The results suggest that the interactions to the clay surfaces are weak and that the present 2D confinement has a very small influence on the time scale of all our observed relaxation processes, except the normal-mode relaxation.

Adsorption↗
PubMed2003

Stress in a case of SAPHO syndrome.

In this article, we describe a case of seemingly stress-induced SAPHO (synovitis, acne, pustulosis, hyperostosis, osteitis) syndrome in a man who exhibited the central features of palmoplantar psoriasis and anterior chest involvement. We also review the etiology, pathogenesis, and treatment of SAPHO syndrome and emphasize the important differences between this syndrome and psoriatic arthritis.

Acquired Hyperostosis Syndrome↗
PubMed2002

Acoustic waves in cylindrical gap, filled by polymeric liquid.

Propagation of acoustic waves in thin-walled elastic tube with coaxial internal rigid rod is investigated in conjugated quasi-one-dimensional formulation. The cylindrical gap between the tube's wall and the central rod is filled by polymeric liquid, described by hereditary model with a discrete spectrum. Dynamics of the tube is treated within Kirchhoff-Love approximation. The dispersion equation accounting for viscoelastic effects in the fluid in coupling with inertia, radial and longitudinal deformations of the tube's wall has been obtained. Its analysis has showed strong influence of the liquid's rheological properties and geometrical parameters of the system on pressure signals dispersion and attenuation. The results can be used for rheological characterization of polymeric liquids by acoustic means.

Journal Article↗
PubMed2002

Radioactive contamination in the Arctic--sources, dose assessment and potential risks.

Arctic residents, whose diets comprise a large proportion of traditional terrestrial and freshwater foodstuffs, have received the highest radiation exposures to artificial radionuclides in the Arctic. Doses to members of both the average population and selected indigenous population groups in the Arctic depend on the rates of consumption of locally-derived terrestrial and freshwater foodstuffs, including reindeer/caribou meat, freshwater fish, goat cheese, berries, mushrooms and lamb. The vulnerability of arctic populations, especially indigenous peoples, to radiocaesium deposition is much greater than for temperate populations due to the importance of terrestrial, semi-natural exposure pathways where there is high radiocaesium transfer and a long ecological half-life for this radionuclide. In contrast, arctic residents with diets largely comprising marine foodstuffs have received comparatively low radiation exposures because of the lower levels of contamination of marine organisms. Using arctic-specific information, the predicted collective dose is five times higher than that estimated by UNSCEAR for temperate areas. The greatest threats to human health and the environment posed by human and industrial activities in the Arctic are associated with the potential for accidents in the civilian and military nuclear sectors. Of most concern are the consequences of potential accidents in nuclear power plant reactors, during the handling and storage of nuclear weapons, in the decommissioning of nuclear submarines and in the disposal of spent nuclear fuel from vessels. It is important to foster a close association between risk assessment and practical programmes for the purposes of improving monitoring, formulating response strategies and implementing action plans.

Agaricales↗
PubMed2002

Atmospheric transport patterns and possible consequences for the European North after a nuclear accident.

The main purpose of this study is to examine possible impacts and consequences of a hypothetical accident at the Kola nuclear plant in north-west Russia on different geographical regions: Scandinavia, central Europe, European FSU and Taymyr. The period studied is 1991-1996. An isentropic trajectory model has been used to calculate forward trajectories that originated over the nuclear accident region. Atmospheric transport patterns were identified using the isentropic trajectories and a cluster analysis technique. From the trajectory model results, a number of cases were chosen for examination in detail using more complete transport models. For this purpose, the models MATHEW/ADPIC, DERMA and a newly developed FOA Random Displacement Model have been used to simulate the radionuclide transport and contamination in the case of a nuclear accident and their results have been compared with those of the trajectory modelling. Estimation of the long-term consequences for populations after an accident has been performed for several specific dates by empirical models and correlation between fallout and doses to humans on the basis of the Chernobyl accident exposures in Scandinavia.

Air Movements↗
PubMed2001

A comparison of three models of 137Cs transfer in forest ecosystems.

The predictions of three models of 137Cs transfer in forest ecosystems (FOA, LOGNAT and FORESTLAND) were compared. The scenario for the model-model comparison consisted of an acute dry deposition of 137Cs over a coniferous forest. The model predictions were subsequently compared (model-data comparison) with values derived from experimental data measured in forests of the Bryansk region in Russia that were contaminated by the Chernobyl accident and that have similar characteristics to the forests described in the scenario. The predictions of radiocaesium levels in the litter-soil layer, berries, needles, wood, whole tree and moose made with the models were in relatively good agreement with each other (within a factor of 1.4-2.9). The best agreement was observed for berries and moose and the worst for wood. There was also good agreement between the model predictions for the same variables and the experimental data (within a factor of 1.2 3.2). In this case, the best agreement was observed for the litter-soil layer and the worst for wood and the whole tree. Overall, at least for the studied scenario and for the first 10 years after deposition, any of the models can be used if the final aim is to estimate average concentrations in different forest components. The agreement between the model predictions worsens with time and there were differences in the form of the time dependencies predicted by the models, especially for wood. This may lead to larger differences between the model predictions and the experimental data for times beyond the period for which data were available for comparison (10 years after the deposition).

Cesium Radioisotopes↗
PubMed2001

Hypotrichosis with juvenile macular dystrophy is caused by a mutation in CDH3, encoding P-cadherin.

Congenital hypotrichosis associated with juvenile macular dystrophy (HJMD; MIM601553) is an autosomal recessive disorder of unknown etiology, characterized by hair loss heralding progressive macular degeneration and early blindness. We used homozygosity mapping in four consanguineous families to localize the gene defective in HJMD to 16q22.1. This region contains CDH3, encoding P-cadherin, which is expressed in the retinal pigment epithelium and hair follicles. Mutation analysis shows in all families a common homozygous deletion in exon 8 of CDH3. These results establish the molecular etiology of HJMD and implicate for the first time a cadherin molecule in the pathogenesis of a human hair and retinal disorder.

Adolescent↗
PubMed2001

MIB-1 monoclonal antibody to determine proliferative activity of Ki-67 antigen as an adjunct to the histopathologic differential diagnosis of Spitz nevi.

BACKGROUND: The histopathologic differential diagnosis of Spitz nevus (SN) from malignant melanoma (MM) may be difficult. OBJECTIVE: Our purpose was to determine the staining pattern and usefulness of MIB-1 antibody, which recognizes Ki-67 antigen in formalin-fixed, paraffin-embedded tissue, as an adjunct to the histopathologic differential diagnosis of SN. METHODS: Twenty-five compound SNs, 27 MMs, and 26 compound nondysplastic melanocytic nevi (MNs) were immunostained with the MIB-1 antibody. RESULTS: The mean counts of MIB-1--stained tumor cells of the epidermal and dermal components, both alone and together, were significantly lower in SNs and MNs than in MMs (P <.0001). The dermal counts showed the best discriminating power. In addition, the mean dermal/epidermal count ratios for MIB-1 in SNs and MNs (0.25 and 0.23, respectively) were significantly lower than the corresponding ratio (0.94) in MMs (P <.0001). CONCLUSION: MIB-1-stained tumor cell counts, especially of the dermal component, and dermal/epidermal MIB-1 count ratios may be helpful as an adjunct to the histopathologic differential diagnosis of SN.

Antibodies, Monoclonal↗
PubMed2001

A case report of olanzapine-induced hypersensitivity syndrome.

Hypersensitivity syndrome is defined as a drug-induced complex of symptoms consisting of fever, rash, and internal organ involvement. The hypersensitivity syndrome is well recognized as being caused by anticonvulsants. Olanzapine is an atypical antipsychotic agent whose side effects include sedation, weight gain, and increased creatinine kinase and transaminase levels. To date, there have been no reports of hypersensitivity syndrome related to this drug. A 34-year-old man developed a severe generalized pruritic skin eruption, fever, eosinophilia, and toxic hepatitis 60 days after ingestion of olanzapine. After termination of olanzapine treatment, the fever resolved, the skin rash was reduced, eosinophil count was reduced to normal, and the transaminase levels were markedly reduced. Clinical features and the results of skin and liver biopsies indicated that the patient developed hypersensitivity syndrome caused by olanzapine.

Adult↗
PubMed2001

Clinicopathologic, immunophenotypic, and molecular characterization of primary cutaneous follicular B-cell lymphoma.

OBJECTIVE: To determine the clinicopathologic, immunophenotypic, and molecular characteristics of primary follicular cutaneous B-cell lymphoma (CBCL) as defined by the revised European-American lymphoma classification. DESIGN: A retrospective survey of the medical records, an immunohistochemical study of archival biopsy specimens. and molecular studies of preserved DNA of all patients with follicle center lymphoma-follicular (FCL-F) primary CBCL from 1987 to 1997. SETTING: A single-center outpatient specialty clinic at an academic medical center. PATIENTS: Twenty-one patients (68% of all new primary CBCL cases), including 14 men and 7 women (age range, 33-88 years; mean, 55 years). RESULTS: The head and neck region was the most frequent primary site. Following treatment, recurrences were relatively frequent, but the overall mortality rate during 1.0 to 11.3 years (mean, 6.3 years) of follow-up was 4.8%. Immunohistochemical analysis for B- and T-cell lineages was helpful in enhancing the folliclelike structures. CD10, bcl-2, and CD43 were expressed by the neoplastic cells in 9 (47%) of 19 cases, 4 (21%) of 19 cases, and 2 (13%) of 16 cases, respectively. Immunohistochemical detection of cytoplasmic immunoglobulin light chains, using steaming in EDTA as the antigen-retrieval technique, was successful in 12 (71%) of 17 cases. The Ig heavy-chain gene rearrangements, using the Southern blot technique, detected clonality in 17 (94%) of 18 cases. The bcl-2 gene rearrangements were detected in only 2 (13%) of 15 of the primary cutaneous FCL-F cases, compared with 9 (75%) of 12 of the primary nodal FCL-F cases (P =.002). CONCLUSIONS: Primary cutaneous FCL-F is a relatively common subtype of CBCL, with a relatively indolent course. It has many features in common with primary nodal FCL-F, except for low rates of bcl-2 expression and bcl-2 gene rearrangements.

Adult↗