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Reuven Bergman

Publications and source records attributed to Reuven Bergman.

At least 19 recordsLinked to original sources
PubMed2006

Classic Kaposi sarcoma. Which KSHV-seropositive individuals are at risk?

BACKGROUND: Classic Kaposi sarcoma (CKS) is a relatively rare vascular disease primarily affecting human immunodeficiency virus (HIV)-uninfected elderly men. The infection with Kaposi sarcoma-associated herpesvirus (KSHV) is necessary for the establishment of Kaposi sarcoma (KS), although it is not sufficient. Thus, only a small fraction of KSHV-infected individuals develops KS. The cofactors that influence risk of KS among HIV-uninfected individuals are yet to be determined. The objective of the current study was to assess potential risk factors for CKS in the KSHV-infected Jewish population in Israel. METHODS: A case-control study involved 35 CKS cases and 48 matched KSHV-infected controls. Lifestyle and medical history data from case patients and controls were compared by logistic regression analysis. RESULTS: In a multivariate analysis, the authors identified an age-related small increased risk for CKS in subjects originating from Asia and Africa. The risk for CKS increased, although not significantly statistically, in subjects who reported alcohol consumption, diabetes mellitus, herpes simplex, and asthma. No relation was found with cigarette smoking, family size, number of lifetime sexual partners, or sexually transmitted disease. CONCLUSIONS: A borderline increase in CKS risk among elderly subjects originating from Africa or Asia was identified. These results need to be further evaluated by larger studies. The authors believe that genetic and immunologic parameters may alter risk for CKS and, therefore, should also be investigated.

Adult↗
PubMed2006

Molecular epidemiology of hereditary epidermolysis bullosa in a Middle Eastern population.

Epidermolysis bullosa (EB) encompasses a large group of inherited blistering skin disorders caused by mutations in at least 10 genes. Numerous studies, mainly performed in European and US families with EB, have revealed a number of characteristic epidemiological and genetic features, which form the basis for current diagnostic and counseling strategies. However, little is currently known about the molecular epidemiology of EB in Middle East populations. In the present study, we assessed 55 EB families for pathogenic sequence alterations in the 10 genes known to be associated with EB. Our results show unique EB subtype distribution and patterns of inheritance in our cohort. We also failed to detect recurrent mutations frequently encountered in Europe and the US, and did not consistently observe genotype-phenotype correlations formerly established in Western populations. Thus, the molecular epidemiology of EB in the Middle East is significantly different from that previously delineated in Europe and the US. Our data raise the possibility that similar differences may also be found in other genetically heterogeneous groups of disorders, and indicate the need for population-specific diagnostic and management approaches.

Asian People↗
PubMed2005

A novel homozygous missense mutation in FGF23 causes Familial Tumoral Calcinosis associated with disseminated visceral calcification.

Hyperphosphatemic Familial Tumoral Calcinosis (HFTC; MIM211900) is a rare autosomal recessive disorder characterized by the progressive deposition of calcified masses in cutaneous and subcutaneous tissues, associated with elevated circulating levels of phosphate. The disease was initially found to result from mutations in GALNT3 encoding a glycosyltransferase. However, more recently, the S71G missense mutation in FGF23, encoding a potent phosphaturic protein, was identified in two families. In the present report, we describe a second mutation in FGF23 underlying a severe case displaying calcifications of cutaneous and numerous extracutaneous tissues. The mutation (M96T) was found to affect a highly conserved methionine residue at position 96 of the protein. These observations illustrate the extent of genetic and phenotypic heterogeneity in HFTC.

Amino Acid Substitution↗
PubMed2005

Targeting perlecan in human keratinocytes reveals novel roles for perlecan in epidermal formation.

Heparin-binding growth factors are crucial for the formation of human epidermis, but little is known about the role of heparan sulfate proteoglycans in this process. Here we investigated the role of the heparan sulfate proteoglycan, perlecan, in the formation of human epidermis, by utilizing in vitro engineered human skin. By disrupting perlecan expression either in the dermis or the epidermis, we found that epidermally derived perlecan is essential for epidermal formation. Perlecan-deficient keratinocytes formed a strikingly thin and poorly organized epidermis because of premature apoptosis and failure to complete their stratification program. Exogenous perlecan fully restored epidermal formation. Perlecan deposition in the basement membrane zone correlated with formation of multilayered epidermis. Perlecan deficiency, however, had no effect on the lining and deposition of major basement membrane components as was evident by a continuous linear staining of laminin and collagen IV. Similarly, perlecan deficiency did not affect the distribution of beta1 integrin. Addition of the perlecan ligand, fibroblast growth factor 7, protected perlecan-deficient keratinocytes from cell death and improved the thickness of the epidermis. Taken together, our results revealed novel roles for perlecan in epidermal formation. Perlecan regulates both the survival and terminal differentiation steps of keratinocytes. Our results suggested a model whereby perlecan regulates these processes via controlling the bioavailability of perlecan-binding soluble factors involved in epidermal morphogenesis.

3T3 Cells↗
PubMed2005

A mutation in SNAP29, coding for a SNARE protein involved in intracellular trafficking, causes a novel neurocutaneous syndrome characterized by cerebral dysgenesis, neuropathy, ichthyosis, and palmoplantar keratoderma.

Neurocutaneous syndromes represent a vast, largely heterogeneous group of disorders characterized by neurological and dermatological manifestations, reflecting the common embryonic origin of epidermal and neural tissues. In the present report, we describe a novel neurocutaneous syndrome characterized by cerebral dysgenesis, neuropathy, ichthyosis, and keratoderma (CEDNIK syndrome). Using homozygosity mapping in two large families, we localized the disease gene to 22q11.2 and identified, in all patients, a 1-bp deletion in SNAP29, which codes for a SNARE protein involved in vesicle fusion. SNAP29 expression was decreased in the skin of the patients, resulting in abnormal maturation of lamellar granules and, as a consequence, in mislocation of epidermal lipids and proteases. These data underscore the importance of vesicle trafficking regulatory mechanisms for proper neuroectodermal differentiation.

Antigens, Polyomavirus Transforming↗
PubMed2005

Infection with Kaposi's sarcoma-associated herpesvirus among families of patients with classic Kaposi's sarcoma.

BACKGROUND: Classic Kaposi's sarcoma (CKS) primarily affects elderly Mediterranean or Eastern European men. Incidence rates of CKS in Israel are among the world's highest. In practically all cases, antibodies against Kaposi's sarcoma-associated herpesvirus (KSHV) can be detected. A relatively high seroprevalence rate of KSHV in Israel generally correlates with the incidence of CKS. A sexual mode of virus transmission is recognized among homosexual men, whereas the precise transmission routes in the heterosexual population and those with CKS are still unclear. OBJECTIVE: To better assess the transmission routes of KSHV in Israeli patients with CKS and their first-degree relatives as compared with a control group. DESIGN: Serum was collected from all study participants and tested for KSHV antibodies by means of latent and lytic immunofluorescence assays. An open reading frame 65 (ORF65) Western blot assay was applied as a confirmatory tool. SETTING: Three dermatological departments in Israel. PATIENTS: Sixty-four Jewish patients with CKS, 143 of their first-degree relatives, and 186 hospital-based control subjects. RESULTS: Seropositivity to KSHV was detected in 62 (96.9%) of the patients with CKS, in 56 (39.2%) of their first-degree relatives, and in only 21 (11.3%) of the hospital controls (P<.001). The specific relationship with the index patient (spouse, offspring, or sibling) had no significant effect on the prevalence of serpositivity in the family members. CONCLUSION: Our serologic evidence of familial clustering of KSHV infection suggests a predominantly nonsexual horizontal transmission route of the virus.

Adolescent↗
PubMed2005

The alopecias associated with vitamin D-dependent rickets type IIA and with hairless gene mutations: a comparative clinical, histologic, and immunohistochemical study.

OBJECTIVE: To establish the unique and common clinical and microscopic characteristics of the alopecias associated with vitamin D-dependent rickets (VDDR) type IIA and with hairless gene mutations. DESIGN: A comparative clinical, histologic, and immunohistochemical study of the alopecias in 6 patients with VDDR IIA and 4 patients with atrichia with papular lesions (APL) and/or alopecia universalis congenita (AUC) (hereinafter "APL/AUC"). MAIN OUTCOME MEASURES: Clinical data were gathered from medical records, personal interviews, and physical examinations. Histologic and immunohistochemical studies were performed on 6 scalp punch biopsy specimens from each of the 2 studied groups. RESULTS: The alopecias in VDDR IIA and APL/AUC showed similar clinical, histologic, and immunohistochemical features. The clinical presentation of the VDDR alopecia resembled either the APL phenotype (ie, with papules and milia) or the AUC phenotype (without papules and milia). The main histologic findings included void infundibula; absence of the lower two thirds of the hair follicles, often replaced by vertically oriented irregular epithelial structures or epithelial cysts; irregular epithelial structures, often with small cysts in the middle and lower dermis; and small, medium, and large keratinizing cysts at all levels of the dermis. The larger epithelial cysts in the upper dermis stained positively for cytokeratin (CK) 10, which suggests an infundibular derivation, whereas the remaining irregular epithelial structures and cysts in the middle and lower dermis stained positively most frequently for CK17, CK19, and CD34, which suggests an outer root sheath derivation. CONCLUSIONS: The alopecias associated with VDDR IIA and with hairless gene mutations show striking clinical and microscopic similarities. Disintegration of the lower two thirds of the hair follicles seems to be the underlying defect, and a common pathogenetic pathway might be involved.

Adolescent↗
PubMed2005

Diffuse nonepidermolytic palmoplantar keratoderma caused by a recurrent nonsense mutation in DSG1.

BACKGROUND: Mutations in genes coding for 2 desmosomal proteins, desmoglein 1 and desmoplakin, have been shown to cause autosomal dominant keratoderma palmoplantaris striata. OBSERVATIONS: We describe a family affected with a diffuse nonstriated form of palmoplantar keratoderma. Histopathologic examination of skin biopsy specimens disclosed cell-cell disadhesion in the suprabasal layers of the epidermis, as previously described in keratoderma palmoplantaris striata. We therefore genotyped all family members using microsatellite markers encompassing 3 keratoderma palmoplantaris striata-associated loci. Haplotype analysis suggested linkage of the disease to 18q12.1, which harbors the DSG1 gene, encoding desmoglein 1. Mutation analysis eventually led to the identification of a causative recurrent nonsense mutation in this gene. CONCLUSIONS: Mutations in DSG1 are not exclusively associated with striated palmoplantar keratoderma. The present study illustrates the efficacy of an integrative diagnostic approach to palmoplantar keratodermas involving clinical assessment, pathologic examination, microsatellite marker screening, and mutational analysis.

Arginine↗
PubMed2005

Familial mycosis fungoides: report of 6 kindreds and a study of the HLA system.

BACKGROUND: The familial occurrence of mycosis fungoides (MF) has been reported only in 8 families. Recently, the HLA class II alleles DRB1* 11 and DQB1* 03 have been found to be significantly increased for patients with sporadic MF, suggesting a possible immunogenetic basis for the pathogenesis of this malignancy. OBJECTIVE: We sought to detect familial occurrences of MF, to describe familial features, and to investigate the possible association or linkage with the HLA system in such cases. METHODS: The files of 300 patients with MF were reviewed to search for familial occurrence in at least two first-degree relatives. A group of 252 healthy unrelated individuals served as control subjects. Tissue typing for HLA class I was performed using the microlymphocytotoxicity technique. DNA-based analysis for DRB1* and DQB1* alleles was performed using polymerase chain reaction amplification. RESULTS: Six families comprising 12 Jewish patients (9 male and 3 female) were detected: in 5, two first-degree relatives had MF; and in one, one member had MF and another had parapsoriasis en plaque. There were 5 families with two affected siblings and one family with a parent-child pair. In all but one family, the age of onset, clinical features, and response to therapy were similar to those in sporadic MF. One family, however, was exceptional: both affected siblings were children and both exhibited a similar but unusual morphology in the form of a hypopigmented variant of MF in conjunction with a psoriasiform variant. The allele frequency of HLA DQB1* 03 was found to be significantly greater among the patients than in the control group (66.7% vs 33%, respectively; P = .027), supporting an association of this allele with familial MF. Analysis of the HLA typing in the affected sibling pairs, when grouped together, did not support linkage to the HLA locus because no segregation distortion could be demonstrated ( P = .76). CONCLUSIONS: Familial aggregation of MF among Israeli Jews may not be as rare as is reflected in the literature. This familial clustering, together with the detection of certain HLA class II alleles with this malignancy (sporadic and familial), suggests that genetic factors may play a role in MF.

Adolescent↗
PubMed2005

Histopathological and ultrastructural study of ectodermal dysplasia/skin fragility syndrome.

Ectodermal dysplasia/skin fragility syndrome (EDSFS) (MIM604536) is a newly described autosomal recessive disorder characterized by skin fragility and blistering, palmoplantar keratoderma, abnormal hair growth, nail dystrophy, and occasionally defective sweating. It results from mutations in the PKP1 gene encoding plakophilin 1 (PKP1), which is an important component of stratifying epithelial desmosomes and a nuclear component of many cell types. Our study was performed to further characterize the histopathology of EDSFS in different cutaneous sites with a special emphasis on the hypotrichosis and keratoderma. A total of 4 biopsies were obtained from 2 EDSFS female patients, aged 9 days to 4 years. The biopsies were taken from the blistering skin of the leg and trunk, the hyperkeratotic skin of the sole, and the hypotrichotic scalp. The observed histopathologic features included: widened intercellular spaces, suprabasal intraepidermal clefts and blisters with acantholytic keratinocytes, detachments of the upper epidermal layers due to disadhesion, varying degrees of dyskeratosis that were much more pronounced in the plantar hyperkeratotic skin, and increased number of catagen-telogen hair follicles. The electron-microscopic observations attributed the disadhesion and acantholysis to reduced numbers of small hypoplastic desmosomes, and the dyskeratosis to the detachment of intracellular keratin filaments from the desmosomes with perinuclear condensation, which might also underlie the plantar keratoderma. The hair follicle findings suggest disturbance in the hair cycle, which might be attributed to disturbed nuclear PKP1 function or result from aberrant desmosomal signaling.

Blister↗
PubMed2005

Absence of intraepidermal glycosyltransferase ppGalNac-T3 expression in familial tumoral calcinosis.

Hyperphosphatemic familial tumoral calcinosis (HFTC) is a rare autosomal recessive disorder characterized by progressive, tumor-like calcifications in the dermis and subcutaneous tissues. The disease is associated with primary hyperphosphatemia due to increased renal tubular reabsorption of phosphate. We recently identified mutations in GALNT3 as the proximal cause of this metabolic disorder. GALNT3 encodes the glycosyltransferase UDP-N-acetyl-alpha-D-galactosamine:polypeptide N-acetylgalactosaminyl-transferase 3 (ppGalNAc-T3), which initiates mucin-type O-glycosylation and thus takes part in posttranslational modification and formation of mucin-type glycoproteins. A number of studies have previously described the histopathological and ultrastructural features of lesional skin in HFTC, but little is currently known about the morphology of the normal-appearing non-lesional skin. We obtained biopsies of uninvolved skin from two HFTC patients carrying a known splice site mutation in GALNT3. Light and electron microscopic examination of a biopsy of one of the two patients did not reveal abnormal findings in the epidermis or dermis. However, immunohistochemical studies of frozen skin sections of biopsies of the two patients using monoclonal antibodies directed against three ppGalNac isoforms revealed the complete absence of immunostaining for ppGalNAc-T3 while the staining pattern for ppGalNAc-T2 and -T6 was identical in skin biopsies obtained from HFTC patients and healthy control individuals. Our data provide for the first time evidence for ppGalNAc-T3 deficiency in the skin of HFTC patients and suggest that immunostaining of skin biopsy samples for ppGal-Nac-T3 might be a useful tool for the diagnosis of HFTC.

Calcinosis↗
PubMed2005

Identification of a novel locus associated with congenital recessive ichthyosis on 12p11.2-q13.

Congenital recessive ichthyoses represent a vast and markedly heterogeneous group of diseases that have been mapped to at least seven distinct chromosomal loci. In this study, we ascertained two consanguineous families presenting with congenital ichthyosis. Using homozygosity mapping, we identified a 6.5 cM homozygous region on 12p11.2-q13 shared by all affected individuals. Multipoint logarithm of odds ratio (LOD) score analysis placed the new locus between markers D12S345 and D12S390 with a maximum LOD score of 4.79 at marker CH12SSR13. This region harbors PPHLN1, encoding periphilin 1, a protein involved in the cornification process. No deleterious mutations were identified within the coding region of this gene, suggesting the existence of another gene associated with epidermal differentiation on 12p11.2-q13.

Antigens, Neoplasm↗
PubMed2005

A comparison of anti-desmoglein antibodies and indirect immunofluorescence in the serodiagnosis of pemphigus vulgaris.

BACKGROUND: Indirect immunofluorescence (IIF) is the standard method for the detection of pemphigus autoantibodies. Commercially available enzyme-linked immunosorbent assays (ELISAs) have recently become available to measure serum antibodies (Abs) against desmoglein1 (Dsg1) and desmoglein3 (Dsg3). It has been suggested that patients with mucosal-dominant pemphigus vulgaris (PV) have serum Abs against Dsg3 only, patients with mucocutaneous PV have Abs to both Dsg1 and Dsg3, and patients with pemphigus foliaceus (PF) have Abs against Dsg1 only. AIM: To compare the sensitivity and specificity of the IIF and ELISA tests in the diagnosis of pemphigus and its subsets. METHODS: Thirty-three patients with PV and five patients with PF were studied, and compared with 50 healthy individuals or patients with unrelated skin diseases. Monkey esophagus was used as a substrate for the IIF test. RESULTS: The IIF and ELISA tests were each positive in 26 of the 32 (81%) PV patients, and in none (0%) and 3 (6%) of the 50 controls, respectively. Both the IIF and ELISA results were concordant in 69% of the PV patients, and only one of these two tests was positive in the remaining 31% of patients. Forty-six per cent of the PV patients with a positive ELISA test did not have the PV phenotype (mucosal or mucocutaneous) predicted by their autoantibody profile. CONCLUSION: The IIF and ELISA tests may be used as complementary tests for the serologic diagnosis of pemphigus.

Adult↗
PubMed2004

Identification of a recurrent mutation in GALNT3 demonstrates that hyperostosis-hyperphosphatemia syndrome and familial tumoral calcinosis are allelic disorders.

Hyperphosphatemia-hyperostosis syndrome (HHS) is a rare autosomal recessive metabolic disorder characterized by elevated serum phosphate levels and repeated attacks of acute, painful swellings of the long bones with radiological evidence of periosteal reaction and cortical hyperostosis. HHS shares several clinical and metabolic features with hyperphosphatemic familial tumoral calcinosis (HFTC), which is caused by mutations in GALNT3 encoding a glycosyltransferase responsible for initiating O-glycosylation. To determine whether GALNT3 is involved in the pathogenesis of HHS we screened two unrelated Arab-Israeli HHS families for pathogenic mutations in this gene. All affected individuals harbored a homozygous splice site mutation (1524+1G-->A) in GALNT3. This mutation was previously described in a large Druze HFTC kindred and has been shown to alter GALNT3 expression and result in ppGalNAc-T3 deficiency. Genotype analysis of six microsatellite markers across the GALNT3 region on 2q24-q31 revealed that the HHS and HFTC families share a common haplotype spanning approximately 0.14 Mb. Our results demonstrate that HHS and HFTC are allelic disorders despite their phenotypic differences and suggest a common origin of the 1524+1G-->A mutation in the Middle East (founder effect). The heterogeneous phenotypic expression of the identified splice site mutation implies the existence of inherited or epigenetic modifying factors of importance in the regulation of ppGalNAc-T3 activity.

Calcinosis↗
PubMed2004

Familial clustering of classic Kaposi sarcoma.

It is widely accepted that there is a causal association between Kaposi sarcoma-associated herpesvirus (KSHV) and Kaposi sarcoma (KS). However, the majority of individuals infected with KSHV never develop KS. Here, we present a unique familial case of classic KS, in which the disease occurs in 4 siblings who have no recognized underlying immunodeficiency. We examine risk factors that could play a role in this condition, including KSHV infection, KSHV DNA load, genetic variants of KSHV, infection with additional viruses, interleukin-6-promoter polymorphism, and HLA genotype. We hypothesize that a genetic susceptibility to KS, in combination with KSHV infection, may play an important role in the presented familial case.

Adult↗
PubMed2004

Mutations in GALNT3, encoding a protein involved in O-linked glycosylation, cause familial tumoral calcinosis.

Familial tumoral calcinosis (FTC; OMIM 211900) is a severe autosomal recessive metabolic disorder that manifests with hyperphosphatemia and massive calcium deposits in the skin and subcutaneous tissues. Using linkage analysis, we mapped the gene underlying FTC to 2q24-q31. This region includes the gene GALNT3, which encodes a glycosyltransferase responsible for initiating mucin-type O-glycosylation. Sequence analysis of GALNT3 identified biallelic deleterious mutations in all individuals with FTC, suggesting that defective post-translational modification underlies the disease.

Base Sequence↗