PubMed Health⌕ Search

Biomedical subjects

J Krutmann

Publications and source records attributed to J Krutmann.

At least 19 recordsLinked to original sources

The effect of processed water on constitutive and ultraviolet-A-radiation-induced level of mitochondrial DNA mutations in human dermal fibroblasts.

The integrity of the mitochondrial genome is of crucial importance for the cellular energy metabolism, and increased mutation rates are causally related to premature ageing. We demonstrate that replacement of normal deionized water with processed water in cell culture medium decreases the constitutive levels of the most frequent large-scale deletion of the mitochondrial genome in human dermal fibroblasts. In addition the presence of processed water also prevented the generation of the common deletion which was induced in these cells by repetitive UVA irradiation (3 x 8 J/cm(2) daily). Thus, processed water appears to protect the mitochondrial genome and may thus exert anti-oxidative and anti-ageing effects.

Cells, Cultured↗

[Systemic photoprotection through carotenoids].

Nutritional supplements are increasingly used to protect human skin against environmentally-induced damage, most importantly as a consequence of ultraviolet radiation exposure. beta-carotene is a major constituent of comercially available products administered for systemic photoprotection. Studies on the systemic use of beta-carotene provide evidence that 15-30 mg/d over a period of about 10-12 wk produces a protective effect against UV-induced erythema. Similar effects have been attributed to mixtures of carotenoids or after long-term intake of dietary products rich in carotenoids. Supplementation with carotenoids contributes to basal protection of the skin but is not sufficent to obtain complete protection against severe UV irradiation.

Administration, Oral↗

Prognostic value of T-1 cell numbers prior to allogeneic stem cell transplantation in patients with severe graft-versus-host disease.

Assessment of risk factors for acute graft-versus-host disease (aGvHD) might help in tailoring the intensity of prophylactic immunosuppression after allogeneic stem cell transplantation (SCT), thereby decreasing the relapse rate in leukaemia patients. In this study, we analysed whether the number of recipient blood T cells and plasma levels of different cytokines were correlated with the risk of aGvHD after allogeneic SCT. Analyses were performed in 23 patients receiving pSCT immediately before or during the first 2 days of the conditioning regimen. In all, 40 or more Tc-1 cells/microl pretransplant were associated with a significantly increased risk of aGvHD (10/10 patients with GvHD>/=II; 4/13 patients without aGvHD with a Tc-1 number >40/microl, P<0.002, Fisher's exact test). In addition, 40 or more Th-1 cells/microl pretransplant were also associated with a significantly increased risk of aGvHD (P<0.04, Fisher's exact test). Furthermore, the number of Th-2 cells was significantly higher in patients with severe aGvHD even though the median absolute cell counts were very low. However, all other investigated parameters did not reveal predictive value. In conclusion, determination of T-1 cells prior to SCT might determine patients with high/low risk of aGvHD and could thus be used to control immunosuppression after SCT.

Adult↗

[Sun protection during holidays].

Ultraviolet radiation is causally involved in induction of skin cancer, premature skin aging and photodermatoses. The longing of our western society for a "healthy tanning" as well as the unbroken trend to spend the holidays in sunny regions lead to the fact that human skin is increasingly exposed to ultraviolet radiation and its detrimental effects. Because of the socio-political importance of the vacation period as the "most beautiful and most important time of the year", effective prevention of these unwanted UV effects has an enormous importance to the general population. In this article the most important methods for effective sun protection are critically discussed.

Adult↗

[Premature skin aging by ultraviolet radiation and other environmental hazards. The molecular basis].

The study of the molecular basis of aging is becoming increasingly important for environmental and dermatological research. In addition to ultraviolet radiation, there are other environmental influences which play a significant role in premature aging processes of the human skin. These include tobacco smoke and, according to recent results, also infrared radiation, ozone and other environmental hazards. Based on our current understanding of the molecular biological basis of the effects of environmental hazards, this overview aims at listing the most important findings which contribute to aging of the skin.

Animals↗

Hohenheimer Consensus Talk. Oxidative and premature skin ageing.

To elucidate the scientific state of the art with respect to the role of nutrition in skin ageing, nine experts from different disciplines discussed the role of micronutrients on 'oxidative and premature skin ageing'. In this 25th Hohenheim Consensus Meeting, 13 questions were discussed and, based on published valid data, answered by mutual agreement. The consensus answers achieved during the meeting are justified by a scientific background text. The importance of in vitro and in vivo models regarding oxidative and premature skin ageing was critically evaluated. There was a special focus on prevention and intervention of skin ageing with nutrition. Finally, the paper summarizes the scientific background from different areas related to oxidative and premature skin ageing.

Animals↗

[Skin aging].

Explore the source record for details and available documents.

Humans↗

[Xeroderma pigmentosum and related syndromes].

Xeroderma pigmentosum, trichothiodystrophy and Cockayne-syndrome are rare, autosomal recessive genodermatoses, which are clinically heterogeneous. Generally, the first signs and symptoms appear at an early age. Although all three syndromes show photosensitivity and an underlying defect in the repair of UV-induced DNA damage, only patients with xeroderma pigmentosum have an increased skin cancer risk. The fact that all three of these syndromes can be caused by mutations in the same gene further emphasizes the role of these syndromes as an important model system for the pathogenesis of skin tumors. Recent findings in the fields of DNA repair, regulation of transcription and immunology have not only further unraveled the underlying mechanisms of these diseases but also provided important insights into the pathogenesis of skin tumors. The clinical characteristics of xeroderma pigmentosum and related DNA repair deficiencies are reviewed with an attempt to point out direct connections between clinical signs and symptoms and their underlying mechanisms.

Adolescent↗

Successful treatment of solar urticaria by extracorporeal photochemotherapy (photopheresis)--a case report.

UNLABELLED: Solar urticaria is characterized by erythema and whealing immediately after exposure to ultraviolet radiation and/or visible light. We report about a patient with severe solar urticaria, who was highly sensitive to both UVA radiation and visible light with a Minimal Urticaria Dose (MUD) of 7 J/cm2 UVA. Management of this patient was extremely difficult because standard treatment with oral antihistamines, hardening with UVA, UVB, visible light or oral PUVA and even oral cyclosporin A were completely ineffective. We therefore decided to perform extracorporeal photochemotherapy (photopheresis, ECP). After nine treatment cycles with photopheresis the MUD increased from 7 J/cm2 UVA before treatment to 22 J/cm2 UVA. This hardening effect was associated with a significant decrease of the frequency and severity of whealing and the accompanying symptoms (pain, fatigue, pruritus). CONCLUSION: Photopheresis might be of some benefit in selected patients with otherwise intractable solar urticaria.

Humans↗

Two individuals with features of both xeroderma pigmentosum and trichothiodystrophy highlight the complexity of the clinical outcomes of mutations in the XPD gene.

The xeroderma pigmentosum group D (XPD) protein is a subunit of transcription factor TFIIH with DNA helicase activity. TFIIH has two functions, in basal transcription and nucleotide excision repair. Mutations in XPD that affect DNA repair but not transcription result in the skin cancer-prone disorder, xeroderma pigmentosum (XP). If transcription is also affected, the result is the multi-system disorder trichothiodystrophy (TTD), in which there is no skin cancer predisposition, or in rare cases, XP combined with Cockayne syndrome. Up till now there have been no reports of combined clinical features of XP and TTD. We have now identified two patients with some features of both these disorders. One of these, XP189MA, a 3-year-old girl with sun sensitivity, mental and physical developmental delay, has XPD mutations not previously reported, and barely detectable levels of nucleotide excision repair. The other, XP38BR, a 28-year-old woman with sun sensitivity, pigmentation changes and skin cancers typical of XP, has a mutation that has been identified previously, but only in TTD patients with no features of XP. The level of repair of UV damage in XP38BR is substantially higher than that in other patients with the same mutation. With both patients, polarized light microscopy revealed a 'tiger-tail' appearance of the hair, and amino acid analysis of the hair shafts show levels of sulfur-containing proteins intermediate between those of normal and TTD individuals. Our findings highlight the complexities of genotype-phenotype relationships in the XPD gene.

Adult↗

[Photocarcinogenesis].

Sunlight-induced skin cancer is the most frequent cancer. Ultraviolet-B (UVB) (290-315 mm) and UVA (320-400 mm) radiation can induce DNA damage with resulting epithelial squamous cell carcinoma and melanoma by causing mutations and immunosuppressive effects that presumably contribute to photocarcinogenesis. The efficacy of photo- and photochemotherapeutic modalities is thought to result, at least in part, from the induction of immunomodulatory effects. In particular, UV radiation has been shown to affect (i) the production of soluble mediators, (ii) the expression of cell-surface receptors and (iii) to induce apoptosis in pathogenetically relevant cells. UVB radiation-induced immunomodulatory effects are limited to the epidermis, whereas UVA radiation-affects both epidermal and dermal cell populations. UVB and UVA radiation can exert essentially identical immunomodulatory effects, which result, however, from different photobiological mechanisms. UVB radiation-induced cyclobutane pyrimidine dimers within the DNA of epidermal cells are detrimental to human health. Photolyase-induced dimer repair completely prevented these UVB radiation-induced immunosuppressive effects as well as erythema and sunburn-cell formation. The Xeroderma pigmentosum (XP) is a rare syndrome of sensitivity to UV due to an inherited defect in nucleotide excision repair or daughter strand repair. Ionising radiation sensitivity is not part of the recognised syndrome. Extreme caution is advised before treating XP patients with radiotherapy. Determining the complementation group and radiosensitivity prior to treatment is recommended.

Animals↗