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T Krieg

Publications and source records attributed to T Krieg.

At least 55 records · Page 3Linked to original sources
PubMed2001

Bullous pemphigoid in a patient treated with UVA-1 phototherapy for disseminated morphea.

Bullous pemphigoid is an autoimmune disease of the skin characterized by the production of antibodies directed at structures of the basement membrane zone (BMZ) leading to subepidermal blisters. Several causative triggers have been described in the literature, among them UV light. Here, we report on a 73-year-old Caucasian female with disseminated morphea who developed blisters on her extremities after receiving whole-body UVA-1 phototherapy. The initial differential diagnosis of a phototoxic versus photoallergic reaction was ruled out as the lesions continued to spread after discontinuation of phototherapy. Histological and direct immunofluorescence examination showing a subepidermal blister and linear IgG deposits along the BMZ along with detection of circulating anti-BMZ antibodies led to the diagnosis of bullous pemphigoid. Immunosuppressive therapy resulted in regression of all blisters. After ruling out other possible causes, such as neoplasias or drugs, we conclude that UVA-1 has to be regarded as the most likely trigger of the disease.

Aged↗
PubMed2001

Gene for the human transmembrane-type protein tyrosine phosphatase H (PTPRH): genomic structure, fine-mapping and its exclusion as a candidate for Peutz-Jeghers syndrome.

Mutations in the serine/threonine kinase STK11 lead to Peutz-Jeghers syndrome (PJS) in a subset of affected individuals. Significant evidence for linkage to a second potential PJS disease locus on 19q13.4 has previously been described in one PJS family (PJS07). In the current study, we investigated this second locus for PJS gene candidates. We mapped the main candidate gene in this region, the gene for the transmembrane-type protein tyrosine phosphatase H (PTPRH), within 15 kb telomeric to the marker D19S880. We determined its genomic structure, and performed mutation analysis of all exons and the exon-intron junctions of the PTPRH gene in the PJS07 family. No disease causing mutation was identified in PTPRH in affected individuals, suggesting the existence of an as yet not identified gene on 19q13.4 as a second PJS gene.

Chromosomes, Human, Pair 19↗
PubMed2001

Apoptosis in v-myc-transfected MSU-1.1 fibroblasts is induced by cell-matrix contact and differs from that of normal dermal fibroblasts.

In order to characterize a fibroblast cell line representing normal human skin fibroblasts in three-dimensional cultures, we compared the fibroblast line MSU-1.1, derived from human foreskin and immortalized by v-myc, to primary human dermal fibroblasts (NDF). Our results demonstrate that in contrast to NDF, all MSU-1.1 fibroblasts die within 3-4 d when cultured within three-dimensional contractile collagen matrices. Also, in contrast to NDF. MSU-1.1 cells die markedly in anchored collagen gels as well. Death is due to apoptosis and is attenuated by addition of antibodies against collagen-recognizing receptors alpha1beta1 and alpha2beta1. Apoptosis of NDF in collagen lattices was repressed by an inhibitor of caspase-1, which was ineffective on apoptosis of MSU-1.1. Further, apoptosis by MSU-1.l fibroblasts was also observed in anchored, i.e., restrained collagen lattices, an environment that supports proliferation of NDF.

Animals↗
PubMed2000

Monocyte chemoattractant protein-1 enhances gene expression and synthesis of matrix metalloproteinase-1 in human fibroblasts by an autocrine IL-1 alpha loop.

Monocyte chemoattractant protein-1 (MCP-1), a member of the C-C chemokine superfamily, has recently been shown to be involved in the pathogenesis of tissue fibrosis. In vitro studies demonstrated that MCP-1 up-regulates type I collagen gene expression via endogenous production of TGF-beta in rat lung fibroblasts. We here show that recombinant human MCP-1 affects gene expression of interstitial collagenase (matrix metalloproteinase-1 (MMP-1)) in primary human skin fibroblasts and a stable fibroblast cell line. MMP-1 mRNA was induced by MCP-1 (10 ng/ml) as early as 6 h and reached a maximal expression at 24 h. MCP-1 also caused an increase of MMP-2 mRNA expression in both types of fibroblasts at 48 h. Interestingly, tissue inhibitor of metalloproteinase-1 (TIMP-1) mRNA was also up-regulated by MCP-1, and TIMP-1 mRNA expression peaked at 48 h in both types of fibroblasts. Immunoblot analysis demonstrated increased levels of MMP-1 and TIMP-1 protein in the culture supernatants of primary fibroblasts stimulated with MCP-1. In addition, MCP-1 strongly induced IL-1 alpha mRNA expression in dermal fibroblasts in parallel with the induction of MMP-1. Preincubation with IL-1 receptor antagonist almost completely abrogated the expression of MMP-1 mRNA, and partially inhibited MMP-1 synthesis induced by MCP-1. Transient transfection of primary skin fibroblasts with a MMP-1 promoter-reporter construct indicated a dose-dependent increase in promoter activity by MCP-1 stimulation. These data demonstrate that MCP-1 up-regulates MMP-1 mRNA expression and synthesis in human skin fibroblasts at a transcriptional level and provide evidence that this is mediated by an IL-1 alpha autocrine loop.

Autocrine Communication↗
PubMed2000

Activation of p70 ribosomal protein S6 kinase is an essential step in the DNA damage-dependent signaling pathway responsible for the ultraviolet B-mediated increase in interstitial collagenase (MMP-1) and stromelysin-1 (MMP-3) protein levels in human dermal fibroblasts.

Ultraviolet B (UVB) irradiation has been shown to stimulate the expression of matrix-degrading metalloproteinases via generation of DNA damage and/or reactive oxygen species. Matrix-degrading metalloproteinases promote UVB-triggered detrimental long term effects like cancer formation and premature skin aging. Here, we were interested in identifying components of the signal transduction pathway that causally link UVB-mediated DNA damage and induction of matrix-degrading metalloproteinase (MMP)-1/interstitial collagenase and MMP-3/stromelysin-1 in human dermal fibroblasts in vitro. The activity of p70 ribosomal S6 kinase, a downstream target of the FK506-binding protein-12/rapamycin-associated protein kinase (FRAP) kinase (RAFT1, mTOR), was identified to be 4.8 +/- 0.8-fold, and MMP-1 and MMP-3 protein levels 2.4- and 11.5-fold increased upon UVB irradiation compared with mock-irradiated controls. The FRAP kinase inhibitor rapamycin and the DNA repair inhibitor aphidicolin significantly suppressed the UVB-mediated increase in p70 ribosomal S6 kinase activity by 50-65% and MMP-1 and MMP-3 protein levels by 34-68% and 42-88% compared with UVB-irradiated fibroblasts. By contrast, the interleukin-1beta-mediated increase in MMP-1 and MMP-3 protein levels could not be suppressed by rapamycin. Collectively, our data suggest that the FRAP-controlled p70 ribosomal S6 kinase is an essential component of a DNA damage-dependent, but not of the interleukin-1/cell membrane receptor-dependent signaling.

Amino Acid Sequence↗
PubMed2000

[Cutaneous metastases from a leiomyosarcoma of the testicular tunica albuginea].

Cutaneous metastases from a leiomyosarcoma of the testicular tunica albuginea are very rare. Primary leiomyosarcomas in this site are uncommon and furthermore cutaneous metastases develop only in 1,4% of all malignant tumors of the internal organs [10]. A 71 year old patient with such a sarcoma underwent primary excision. Nine months later multiple, firm, nodules were identified as cutaneous metastases. Further staging revealed already extensive, diffuse pulmonary and bony metastases without contiguous or regional lymph node involvement.

Aged↗
PubMed2000

Bleomycin increases steady-state levels of type I collagen, fibronectin and decorin mRNAs in human skin fibroblasts.

Bleomycin is a drug capable of inducing tissue fibrosis. In this study, the effects of bleomycin on gene expression of extracellular matrix encoding alpha1(I) collagen, fibronectin and decorin were determined in vitro in human dermal fibroblasts. Northern blot analysis showed that bleomycin upregulated alpha(I) collagen, fibronectin and decorin gene expression dose-dependently between 1 nM and 1 microM. Bleomycin at 100 nM upregulated alpha1(I) collagen, fibronectin and decorin mRNA expression with a peak at 6 h following stimulation in normal skin fibroblast monolayers. Bleomycin enhanced mRNA expression encoding these extracellular matrix proteins in both normal dermal and scleroderma fibroblasts. Concomitant stimulation with bleomycin and interferon-gamma (1,000 U/ml), a representative antifibrotic cytokine, decreased alpha1(I) collagen mRNA expression. Bleomycin also mildly upregulated mRNA expression of transforming growth factor-beta (TGF-beta) and connective tissue growth factor (CTGF) coordinately in normal skin fibroblasts. Our results indicate that bleomycin modulates gene expression of extracellular matrix proteins in dermal fibroblasts, and this effect may be mediated by TGF-beta and CTGF.

Anti-Bacterial Agents↗
PubMed2000

Fibroblast-matrix interactions in wound healing and fibrosis.

The regulation of matrix deposition is a key event in many physiological and pathological situations. It involves the activity of mediators in autocrine and paracrine fashions and the contact of cells with the surrounding extracellular matrix as well. The tightly regulated balance of both mechanisms guarantees rapid and adaptive cellular responses to meet changes in the biological requirements of the environment. Disturbances lead to wound healing defects or the development of fibrosis. The molecular mechanisms for these regulatory events are only partially understood, but involve the activity of integrins and a structural continuum of extracellular matrix-receptor-cytoskeleton-nucleus for transfer of information and the regulation of activated genes.

Collagen↗
PubMed2000

Pseudoscleroderma associated with lung cancer: correlation of collagen type I and connective tissue growth factor gene expression.

Pseudoscleroderma as a paraneoplastic syndrome is a rare disease. We report here a patient with lung cancer (undifferentiated squamous cell carcinoma), who developed acrosclerosis. Using in situ hybridization, marked expression of alpha1(I)-collagen and connective tissue growth factor (CTGF) mRNA was found in fibroblasts scattered throughout the dermis. However, transforming growth factor (TGF)-beta1 expression was not detected. The pattern of CTGF gene expression and collagen synthesis was similar to that in systemic scleroderma. The absence of TGF-beta1 mRNA could indicate that tumour-derived factors induce the expression of CTGF.

Aged↗
PubMed2000

Treatment of pruritus by capsaicin in a patient with pityriasis rubra pilaris receiving RE-PUVA therapy.

Pityriasis rubra pilaris (PRP) is characterized by redness of the skin, scaling and a variable degree of pruritus. We present a patient with extremely itchy PRP successfully treated with oral retinoids and photochemotherapy with 8-methoxypsoralene (RE-PUVA) and topical capsaicin. The PRP-related pruritus which clearly preceded photochemotherapy and for which no other cause was apparent was relieved with capsaicin. This single case report provides evidence that topical capsaicin may be a useful therapeutic option in treating PRP-associated pruritus where antihistamines have been unsuccessful.

Capsaicin↗
PubMed2000

Discrete papular mucinosis-a rare subtype of lichen myxoedematosus.

Lichen myxoedematosus is an uncommon and distinct disease entity characterized by cutaneous mucin deposition which, depending on the distribution and overall skin involvement, can be classified into several subtypes. We now describe the case of a discrete papular type of lichen myxoedematosus in a patient without any conspicious laboratory findings including normal thyroid function and the absence of any abnormal immunglobulins.

Diagnosis, Differential↗
PubMed2000

Foreword

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Journal Article↗
PubMed2000

Mast cells enhance contraction of three-dimensional collagen lattices by fibroblasts by cell-cell interaction: role of stem cell factor/c-kit.

Reorganization of the extracellular matrix is important in many biological and pathophysiological processes, including tissue remodelling, wound healing, or cancer metastasis. The ability of cultured fibroblasts to reorganize and contract three-dimensional type I collagen gels is regarded as an in vitro model for this process. In tissue fibrosis, complex interactions among fibroblasts, inflammatory cells and the extracellular matrix are taking place. Mast cells have often been discussed to play a role in several fibrotic conditions including scleroderma, scar formation, or wound healing. In this study, we examined the effects of mast cells on contraction of collagen lattices. The results demonstrate that co-culture of dermal fibroblasts with a human mast cell line (HMC-1) significantly enhanced contraction of the three-dimensional collagen lattices, whereas mast cells alone failed to contract the gel. Addition of culture supernatants of mast cells did not enhance the speed of gel contraction, indicating the importance of cell-cell contact. Morphological analysis showed that mast cells were incorporated into the lattices. Histological examination also demonstrated that within the lattices, mast cells were localized in close contact to, or attached to, fibroblasts. As fibroblasts and mast cells are known to attach via stem cell factor (SCF)/c-kit interaction when co-cultured in monolayers, we also examined the effect of antibodies against SCF and c-kit in this system. Addition of both antibodies inhibited gel contraction up to 70%. In contrast, antibodies against interleukin-4 (IL-4) and IL-4 receptor did not affect gel contraction. These results indicate that mast cells enhance fibroblast-mediated contraction of collagen lattices via direct cell-cell contact, mediated in part by SCF/c-kit interactions.

Antibodies↗
PubMed2000

Expression and proteolysis of vascular endothelial growth factor is increased in chronic wounds.

Degradation of angiogenic mediators might be an underlying cause of chronic wounds. To test this hypothesis, we evaluated the expression and integrity of vascular endothelial growth factor, a potent angiogenic mediator, and its receptors, Flt-1 and KDR, in chronic venous leg ulcerations. Immunohisto- chemical, in situ hybridization, and semiquantitative reverse transcriptase polymerase chain reaction analyses all indicate that expression of vascular endothelial growth factor is elevated in ulcerative tissue, with vascular endothelial growth factor mRNA being especially pronounced in the hyperplastic epithelium of the wound margin. Flt-1 and KDR protein and mRNA were detected in the papillary vessels in close vicinity to the lesional epithelium of chronic wounds. Although increased expression of vascular endothelial growth factor protein was detected in the epidermis, the intensity of this staining was weak compared with the epidermal staining in psoriatic lesions and compared with the strong vascular endothelial growth factor mRNA signal in chronic wounds and psoriasis. To analyze whether this apparent decrease in immunoreactivity could be the result of degradation of vascular endothelial growth factor by proteolytic activities from the wound environment, we examined the stability of recombinant vascular endothelial growth factor in wound fluid from chronic leg ulcers. As demonstrated by sodium dodecyl sulfate polyacrylamide gel electrophoresis, incubation of rVEGF165 with chronic, but not acute, wound fluid resulted in rapid proteolytic degradation of rVEGF165. Protease inhibitor studies indicate that serine proteases, such as plasmin, are involved in this degradation. Together, our data show that, although vascular endothelial growth factor expression is elevated in chronic wounds, increased proteolytic activity in this environment results in its degradation, which may contribute to an impaired wound healing response.

Chronic Disease↗
PubMed2000

Erythroplasia of queyrat: coinfection with cutaneous carcinogenic human papillomavirus type 8 and genital papillomaviruses in a carcinoma in situ.

Erythroplasia of Queyrat is a carcinoma in situ that mainly occurs on the glans penis, the prepuce, or the urethral meatus of elderly males. Up to 30% progress to squamous cell carcinoma. The cause of erythroplasia of Queyrat is largely unknown. Human papillomavirus type 16 DNA has previously been detected only in very few distinctly characterized patients. We have investigated 12 paraffin-embedded biopsies from eight patients with penile erythroplasia of Queyrat and control biopsies of inflammatory penile lesions, of genital Bowen's disease, and of premalignant/malignant cervical or vulvar lesions by 10 different polymerase chain reaction protocols for the presence of cutaneous and genital/mucosal human papillomaviruses. Human papillomavirus typing was performed by sequencing (cloned) polymerase chain reaction products. Human papillomavirus DNA was detected in all erythroplasia of Queyrat patients and in none of the controls with inflammatory penile lesions. The rare cutaneous carcinogenic epidermodysplasia verruciformis-associated human papillomavirus type 8 was present in all erythroplasia of Queyrat patients and the genital high-risk human papillomavirus type 16 in seven of eight patients (88%). In addition to human papillomavirus type 8 and human papillomavirus type 16, four patients carried the genital carcinogenic human papillomavirus type 39 and/or type 51. All human papillomavirus type 8 sequences found in erythroplasia of Queyrat showed some polymorphism among each other and differed in specific nucleotide exchanges from the human papillomavirus type 8 reference sequence. Viral load determinations (human papillomavirus copies/beta-globin gene copies) by realtime polymerase chain reactions showed that the human papillomavirus type 16 levels in the erythroplasia of Queyrat biopsies were one to five orders of magnitude higher than the human papillomavirus type 8 levels. Human papillomavirus type 8 was not detected in cervical or vulvar precancerous and cancerous lesions and in Bowen's disease lesions that carried genital human papillomavirus types. The data suggest that in erythroplasia of Queyrat, in contrast to other genital neoplasias, a coinfection with human papillomavirus type 8 and carcinogenic genital human papillomavirus types occurs. The presence or absence of human papillomavirus type 8 might help to distinguish between penile erythroplasia of Queyrat and Bowen's diseases.

Aged↗