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E Frenk

Publications and source records attributed to E Frenk.

At least 19 recordsLinked to original sources
PubMed2006

Confirmation of the origin of NISCH syndrome.

Neonatal ichthyosis-sclerosing cholangitis (NISCH) syndrome, a rare autosomal recessive ichthyosis syndrome characterized by scalp hypotrichosis, scarring alopecia, ichthyosis, and sclerosing cholangitis, was described for the first time in 2002. It is caused by a mutation in the gene coding for the tight junction protein claudin-1. Only four patients carrying the same mutation of the CLDN1 gene have been described until now. We report a patient presenting with the clinical characteristics of NISCH syndrome and carrying a novel mutation in the CLDN1 gene.

Adolescent↗
PubMed2000

Induction of the putative protective protein ferritin by infrared radiation: implications in skin repair.

The modification of ferritin in human skin cells in vitro and in vivo following infrared-A irradiation by immunohistochemical analysis and ELISA were evaluated. In addition, we observed that IR-A is not capable of inducing frank damage to DNA (pyrimidine dimers, p53), induction of oxidative stress proteins (heme oxygenase, nitric oxide, superoxide dismutase, heat shock proteins) or proteases (collagenase, stromelysin, gelatinase) involved in carcinogenesis and photoaging of the skin. in vivo, basal levels of ferritin were heterogeneous for all individuals tested but all showed ferritin to stain precisely in the basal layer of unirradiated epidermis. Following IR-A radiation, the ferritin increase was localized to epidermal tissue and showed an increase from 120 to 220%. Parallel to the in vivo analysis, dermal fibroblasts were cultured from six individuals. Quantitative analysis for ferritin in cultured fibroblasts was assessed by ELISA and increases were seen to be dose-dependent and up to 130% of basal levels of ferritin following infrared-A. Our findings indicate that the putative defense system of ferritin that exists in human skin in vivo can be induced by infrared-A radiation and that these wavelengths may prove to be beneficial for human skin. Importantly, following the same doses of IR-A that induced ferritin levels, there was no alteration seen for nuclear DNA type damage, oxidative stress proteins or proteases involved in the degradation of skin. The increased concentrations of this antioxidant in human skin following acute UV radiation could afford increased protection against subsequent oxidative stress.

Adult↗
PubMed1999

In vivo induction of pyrimidine dimers in human skin by UVA radiation: initiation of cell damage and/or intercellular communication?

Pyrimidine dimers participate as important factors in ultraviolet-induced lethality, mutagenicity and tumorgenicity. Substantial efforts have been made in recent years to understand the induction of pyrimidine photodimers and their repair in human skin cells exposed to low physiological fluences of UV-light. Dimers are known to be efficiently induced after UVC and UVB irradiation, but these photoproducts are also highly induced in DNA isolated from human skin irradiated with UVA. By using a sensitive immunohistochemistry dimer detection assay, we confirm that in vivo UVA radiation induces substantial amounts of these DNA changes in the epidermis; in addition, this technique detects them far into the reticular dermis. A considerable number of these photodimers were also seen in non-irradiated control skin up to two centimeters from the irradiation site. All the lesions persist for at least two days post-irradiation. These results sustain the hypothesis that pyrimidine dimer formation and excision could be a modality of epidermal communication.

Adult↗
PubMed1998

Sunlight and carcinogenesis: expression of p53 and pyrimidine dimers in human skin following UVA I, UVA I + II and solar simulating radiations.

DNA damage by UV radiation plays an essential role in skin cancer induction. We report that even sub-erythemal doses of solar simulating radiation, are capable of inducing substantial nuclear damage, namely pyrimidine dimers and p53 induction in human skin in situ. The quantity and distribution of p53 induced in human skin by UV radiation depended highly on the waveband and dose of UV used. Solar simulating radiation induced very high levels of p53 throughout all layers in epidermal keratinocytes 24 hr following an erythemal dose (230+/-15.9/1000 cells), and the induction followed a dose response. Following UVA I + II and UVA I radiations, p53 expression was approximately half of that seen with equivalent biological doses of solar simulating radiation (63.5+/-28.5 and 103+/-15.9, respectively). Expression of p53 was seen in basal cell keratinocytes at lower doses of UVA, but all layers of the epidermis were affected at higher doses. Pyrimidine dimer induction, however, was seen to be the same for equivalent biological doses of UVA I, UVA I + II and solar simulating radiations, which coincides with previous findings that pyrimidine dimers initiate the erythemal response and are implicated in skin carcinogenesis. When equivalent biological doses of pure UVA are used with no UVB contamination, significant nuclear alterations occur in human skin in situ, which can approach those seen with UVB radiation. Our results suggest that DNA damage assessed in vivo by immunohistochemistry could provide a very sensitive endpoint for determining the efficacy of protective measures, such as sunscreens or protective clothing, against both UVB- and UVA-induced damage in human skin.

Adult↗
PubMed1998

Evidence that ferritin is UV inducible in human skin: part of a putative defense mechanism.

As ferritin has been identified as an important factor in antioxidant defense in cultured human skin cells we evaluated the presence of ferritin in human skin in vivo and the modifications following irradiation with UVA I, UVA I + II, and solar simulating light by immunohistochemical analysis. We report that the putative protective protein ferritin is regularly present in the basal layer of unirradiated epidermis in vivo and that the induction of ferritin was dependent on wavelength and cell type. Following UVA I radiation, ferritin increased both in epidermal and in dermal tissue. The same response occurred, although to a lesser extent, with UVA I + II but did not occur following solar simulating radiation. Quantitative analysis for ferritin in cultured keratinocytes and fibroblasts from seven individuals following each UV spectra were also assessed by enzyme-linked immunosorbent assay. The induction of ferritin by UV was highly dependent on the waveband and cell type. UVA I and UVA I + II radiations induced ferritin expression in dermal fibroblasts up to 260% and 200% over basal levels, respectively. Solar simulating radiation produced only a small induction of approximately 130% over basal ferritin levels in dermal fibroblasts. Ferritin increased in cultured fibroblasts as early as 3 h post-UVA with a peak at 6 h that remained until 48 h; there was no observable qualitative or quantitative increase seen in the undifferentiated cultured epidermal keratinocytes. Our findings indicate that the putative defense system of ferritin exists in human skin in vivo and its induction is dependent on UV spectra and cell type. The increased concentrations of this antioxidant in human skin following acute UV radiation could afford increased protection against subsequent oxidative stress.

Adult↗
PubMed1997

Severe, chronic anorexia and extensive leg ulcerations as presenting signs of primary Sjögren's syndrome.

We report the case of a 75-year-old woman with a 15-year history of inappetance resulting in weight loss of approximately 40 kg. On physical examination, the skin of the lower extremities was markedly hyperpigmented with a brown-greyish hue. In addition, the skin of the legs was infiltrated, erythematous, riddled with erosions and necrotic ulcers. Clinical and laboratory evaluation revealed sicca syndrome, a pronounced polyclonal hypergammaglobulinemia (60 g/l), high levels of antinuclear, anti-SSA and anti-SSB antibodies. Histological examination of involved skin demonstrated a leukocytoclastic vasculitis.

Adenosine Triphosphatases↗
PubMed1997

Erythema induction by ultraviolet radiation points to a possible acquired defense mechanism in chronically sun-exposed human skin.

BACKGROUND: It is generally accepted that a UVA-induced erythema is difficult to detect except in the most sensitive individuals. OBJECTIVE AND METHODS: As UVA effects on human skin and skin cells have been shown to depend strongly on anatomical body sites, UVA I, UVA I + II and solar simulator radiations were compared in their ability to induce erythema and melanin pigmentation responses in individuals with skin types I-IV on both previously sun-exposed (arms, forearms, thighs) and nonexposed body sites (buttocks). RESULTS: Erythema induction by UVA I on previously nonexposed skin sites followed a dose response in all skin types which was contrary to the absence of erythema induction seen on previously sun-exposed sites. Melanin expression followed a dose and skin type response and was shown to be more enhanced in previously exposed skin and in skin types III and IV. In contrast, UVA I + II induced erythema on nonexposed skin areas and to a lesser extent on frequently sun-exposed skin. Melanin production by UVA I + II was similar to that seen with UVA I alone in individuals of skin types II and III. Solar simulator radiation was very efficient in erythema induction regardless of previous sun exposure of skin. CONCLUSIONS: We have found that contrary to the widespread opinion that UVA and in particular UVA I could not induce a significant erythema, this waveband is capable of measurable erythema induction on skin nonexposed to sunlight. The diminished erythema induction by UVA I on chronically sun-exposed skin suggests the possibility of a defense mechanism against UVA-induced damage in this tissue.

Adult↗
PubMed1997

[Amiodarone induced iododerma treated by cyclosporine].

INTRODUCTION: Iodine containing agents are used as radiologic contrast media and for the treatment of upper respiratory infections, heart diseases, thyreotoxicosis, erythema nodosum and wound disinfection. Vegetating iododerma is a rare but severe cutaneous side effect. CASE STUDY: We report a case of iododerma in a 84 year-old patient, presenting iododerma 14 months after introduction of amiodarone treatment. Despite cessation of this therapy, an important exacerbation of the skin lesions was observed 3 months later. Therapy with cyclosporine produced a marked regression of the skin lesions. DISCUSSION: We are aware of only one other reported case of amiodarone induced iododerma, which occurred after 2 years of therapy. Our patient was also exposed to iodine containing radiographic contrast media 1 and 18 years before onset of the actual skin disease. A sensitizing role of these injections is possible, but we feel that they did not directly induce the skin eruption as all reported cases occurred within a few days after exposure. CONCLUSION: Amiodarone can exceptionally be responsible for severe iododerma. Cyclosporine is, according to our experience, a valuable therapeutic option.

Aged↗
PubMed1996

Susceptibility of human melanoma cells to oxidative stress including UVA radiation.

Ultraviolet radiation, and in particular UVA (320-400 nm), induces significant oxidative stress to human skin. Ferritin and glutathione have been shown to be among the more important molecules within human skin cells providing protection against this damage, the presence of lower levels of these anti-oxidants giving rise to increased cellular sensitivity to stress. We compared endogenous levels of ferritin and glutathione in human melanoma cells with normal human skin fibroblasts and keratinocytes, also the response of melanoma cells to oxidative stress with fibroblasts and keratinocytes. Ferritin levels were heterogenous in the untreated melanoma cell lines tested and remained the same following oxidative stress (UVA radiation) or hemin treatment. Epidermal keratinocytes were unaffected, as were the melanoma cell lines, but skin fibroblasts showed dose-dependent ferritin depletion. Similar results were seen for glutathione alterations resulting from UVA radiation: melanoma cell lines and epidermal skin keratinocytes remained unchanged following UVA radiation, while skin fibroblasts showed dose-dependent depletion. Our results show that human melanoma cells have low ferritin and glutathione levels, yet are resistant to oxidative stress.

Adult↗
PubMed1996

Ichthyosiform dermatosis with superficial blister formation and peeling: evidence for a desmosomal anomaly and altered epidermal vitamin A metabolism.

We describe a man with generalized congenital ichthyosiform dermatosis, severe cheilitis, and palmar and plantar hyperkeratosis with superficial blistering. Low-dose acitretin therapy induced areas of peeling skin, similar to that seen in the peeling skin syndrome. Histologically, the skin was moderately hyperkeratotic and the palmar blisters were subcorneal. Electron microscopy revealed that the splitting occurred within the desmosomal plaque. Ultrastructural and biochemical investigations indicated epidermal hypervitaminosis A, probably related to alteration of epidermal retinoic acid metabolism. This disease is proposed as a hitherto unreported variant of the peeling skin syndrome.

Adolescent↗
PubMed1996

Positional cloning of a gene for Hermansky-Pudlak syndrome, a disorder of cytoplasmic organelles.

Hermansky-Pudlak syndrome (HPS) is an often-fatal autosomal recessive disease in which albinism, bleeding, and lysosomal storage result from defects of diverse cytoplasmic organelles: melanosomes, platelet dense bodies, and lysosomes. HPS is the most common single-gene disorder in Puerto Rico, with an incidence of 1 in 1,800. We have identified the HPS gene by positional cloning, and found homozygous frameshifts in this gene in Puerto Rican, Swiss, Irish and Japanese HPS patients. The HPS polypeptide is a novel transmembrane protein that is likely to be a component of multiple cytoplasmic organelles and that is apparently crucial for their normal development and function. The different clinical phenotypes associated with the different HPS frameshifts we observed suggests that differentially truncated HPS polypeptides may have somewhat different consequences for subcellular function.

Albinism, Oculocutaneous↗
PubMed1996

Meleda disease: report of two cases investigated by electron microscopy.

We report 2 cases of clinically typical Meleda disease in a family from Herzegovina. Electron microscopy did not reveal major ultrastructural anomalies of keratinization; however, the transition from stratum granulosum to stratum corneum appeared to occur less abruptly than normally by a stepwise process suggesting a slowing down of terminal cornification.

Adult↗
PubMed1996

Acrodermatitis enteropathica secondary to Crohn's disease.

A patient suffering from Crohn's disease (CD) presented with alopecia, eczematoid and psoriasiform lesions located on the extremities, around the orifices and at pressure points, suggesting acrodermatitis enteropathica. Lately, her inflammatory bowel disease had flared up with abdominal pain, diarrhea and weight loss related to a retroperitoneal abscess. Acrodermatitis enteropathica due to zinc deficiency is a well-known complication of CD. In our patient the etiological factors involved appeared to be multiple.

Acrodermatitis↗
PubMed1996

Expression of intercellular adhesion molecule-1 in UVA-irradiated human skin cells in vitro and in vivo.

Ultraviolet A (UVA) radiation represents an important oxidative stress to human skin and certain forms of oxidative stress have been shown to modulate intercellular adhesion molecule-1 (ICAM-1) expression. ICAM-1 has been shown to play an important part in many immune reactions and the perturbations of this molecule by ultraviolet radiation could have implications in many inflammatory responses. An enhancement immunohistochemical method with avidin/biotin was used for analysing the early effects of UVA radiation on human cell cultures and human skin (340-400 nm). Both in vitro and in vivo data show that ICAM-1 staining in epidermal keratinocytes, which was expressed constitutively, decreased in a UVA dose-dependent manner. The decrease was most noted at 3-6 h following UVA radiation with some ICAM-1 staining returning by 48 h post-UVA. ICAM-1 positive staining in the dermis was specific for vascular structures and was increased 24 h after UVA radiation. Cultured dermal fibroblasts exhibited ICAM-1 staining which increased slightly within 6-48 h post-UVA radiation. As epidermal ICAM-1 expression is depleted following UVA radiation and dermal expression increases due to an increase in the vascular structures, ICAM-1 provides a valuable marker following UVA radiation in human skin that can be readily measured in situ.

Adult↗
PubMed1995

Mutations of keratinocyte transglutaminase in lamellar ichthyosis.

Lamellar ichthyosis is a severe congenital skin disorder characterized by generalized large scales and variable redness. Affected individuals in three families exhibited drastically reduced keratinocyte transglutaminase (TGK) activity. In two of these families, expression of TGK transcripts was diminished or abnormal and no TGK protein was detected. Homozygous or compound heterozygous mutations of the TGK gene were identified in all families. These data suggest that defects in TGK cause lamellar ichthyosis and that intact cross-linkage of cornified cell envelopes is required for epidermal tissue homeostasis.

Base Sequence↗