bluuebunny/crossref_metadata_2025 huggingface dataset:
Experimental induction of anterior disk displacement of the rabbit craniomandibular joint: an immuno‐electron microscopic study of collagen and proteoglycan occurrence in the condylar cartilage
Authors: Sharawy Mohamed , Ali Ayman M. , Choi Won‐Seok
Published: March 2003

Background:  Results from our previous studies suggest that surgical induction of anterior disk displacement (ADD) in the rabbit craniomandibular joint (CMJ) leads to histopathological alterations consistent with osteoarthritis. In addition, molecular changes in collagens and glycosaminoglycans (GAGs) were observed using immunohistochemistry. The purpose of the present study was to further characterize those molecular changes in collagens and GAGs using immuno‐electron microscopy.

Methods:  The right joint of 15 rabbits was exposed surgically and all discal attachments were cut except for the posterior attachment (the bilaminar zone). The disc was then repositioned anteriorly and sutured to the zygomatic arch. The left joint was used as a sham‐operated control. Ten additional joints were used as non‐operated controls. Mandibular condyles were removed 2 weeks following surgery and processed for light and immuno‐electron microscopy using colloidal gold‐labeled antibodies against collagen type I, II, VI and IX and against keratan sulfate, chondroitin‐4 and ‐6‐sulfate, and link protein.

Results:  Light microscopic results showed osteoarthritic changes. Immuno‐electron microscopy of osteoarthritic cartilage demonstrated a decline in type II collagen, the abnormal presence of type I collagen and loss of type VI and IX collagens. Quantitative colloidal gold immuno‐electron microscopy confirmed the depletion of keratan sulfate, chondroitin‐4 and ‐6‐sulfate, and link protein in osteoarthritic cartilage.

Conclusion : Anterior disk displacement leads to molecular alterations in both the collagen and the proteoglycans of rabbit condylar cartilage characteristic of osteoarthritis in other synovial joints. These alterations are consistent with loss of the shock absorber function of the cartilage and injury of the underlying bone.
Non‐functioning adrenal cortical carcinoma presenting with metastasis to the tongue
Authors: Dominici Alberto , Rizzo Michelangelo , Travaglini Fabrizio , Nesi Gabriella , Franchi Alessandro
Published: March 2003

We report a case of non‐functioning adrenal cortical carcinoma (ACC) presenting with metastatic disease to the tongue, which is an extremely uncommon onset for this neoplasm. Histologically, the lesion had the appearance of an anaplastic neoplasm, and a panel of immunohistochemical markers including vimentin, MART‐1, S100 protein, HMB‐45, smooth muscle actin, common muscle actin, desmin, CD31, CD34, CD68, EMA and cytokeratins, was helpful in excluding melanoma, as well as other mesenchymal and epithelial neoplasms.
Latanoprost Stimulates Eumelanogenesis in Iridial Melanocytes of Cynomolgus Monkeys
Authors: PROTA GIUSEPPE , VINCENSI MARIA ROSARIA , NAPOLITANO ALESSANDRA , SELEN GORAN , STJERNSCHANTZ JOHAN
Published: March 2003

Latanoprost, the active principle of XalatanR eye drops, is a prostaglandin F2α analogue in widespread use for the treatment of glaucoma. During chronic treatment with the drug, an increased pigmentation of the iris was observed in both primates and man. To gain an insight into the nature of this effect, we analyzed the stroma of the irides of cynomolgus monkeys subjected to 25–38 weeks of treatment. A highly sensitive procedure, based on chemical degradation by alkaline hydrogen peroxide oxidation, or hydriodic acid hydrolysis, was developed, which allowed eumelanin and pheomelanin analysis of a single iris at a time. Untreated monkey irides were found to be essentially pheomelanic, providing further support to the recently reported occurrence of these pigments in human irides. In the Latanoprost‐treated eyes, the amount of eumelanin increased from three to sevenfold, while the variation of pheomelanin did not exceed 25%. The increase in eumelanin/pheomelanin ratio in the treated eyes, as compared with the contralateral control eyes, varied from three to fivefold, and the change was statistically significant (P<0.01; t‐test). Based on the results of parallel studies, showing that Latanoprost does not induce proliferation of iridial melanocytes, and that the other pigmented layers of the iris which do not contain melanocytes are not affected by the drug, it can be concluded that the observed effect is a result of a direct interaction with the melanogenic mechanism. This probably involves activation of tyrosinase, as suggested, to account for the stimulation of melanin synthesis by related compounds, including natural prostaglandins.
Small GTPase Rab3A is Associated with Melanosomes in Melanoma Cells
Authors: ARAKI KEISHI , HORIKAWA TATSUYA , CHAKRABORTY ASHOK K. , NAKAGAWA KOICHI , ITOH HIROSHI , OKA MASAHIRO , FUNASAKA YOKO , PAWELEK JOHN , ICHIHASHI MASAMITSU
Published: March 2003

Rab3A is a small guanosine triphosphate (GTP)‐binding protein that has been recently implicated in intracellular vesicle transport and the secretion of neurotransmitters in neuronal cells. We demonstrate here that Rab3A is associated with melanosomes in pigment cells. Rab3A as well as Rabphilin3A, a putative target protein of Rab3A, were detected in the melanosome fraction, purified from B16 murine melanoma cells by sucrose density gradient ultracentrifugation. In contrast, Rab GDP dissociation inhibitor (GDI), a GDP/GTP exchange protein for Rab3A, was found in the cytosol fraction. Further studies using confocal laser scanning microscopy and immunoelectron microscopy revealed that immunoreactive Rab3A is localized in conjunction with the melanosomal membrane. These results suggest the possibility of involvement of Rab3A–Rabphilin3A complex, regulated by Rab GDI, in the intracellular transport of melanosomes in pigment cells.
Up‐Regulation and Redistribution of Bax in Ultraviolet B‐Irradiated Melanocytes
Authors: KIM YOUNG GULL , KIM HYE JIN , KIM DONG SEOK , KIM SANG DUK , HAN WON SUK , KIM KYU HAN , CHUNG JIN HO , PARK KYOUNG CHAN
Published: March 2003

Ultraviolet B (UVB) radiation may activate or deteriorate cultured human epidermal melanocytes, depending on the doses and culture conditions. It is also reported that cultured human epidermal melanocytes derived from different pigmentary phenotypes showed different responses to UVB radiation. In this study, we examined whether apoptosis of melanocytes can be induced by physiologic doses of UVB irradiation using cultured human epidermal melanocytes derived from oriental males of skin types III and IV. Propidium iodide staining for DNA condensation and flow cytometric analyses demonstrated the apoptotic cell death of melanocytes following UVB irradiation (0–30 mJ/cm2). The levels of p53, Bax, and Bcl‐2, determined by immunoblotting, revealed a dose‐dependent increase in p53 and Bax, but the level of Bcl‐2 remained unchanged. Confocal microscopic examination showed that Bax moved from a diffuse to a punctate distribution after UVB irradiation. However, there were no changes in the pattern of distribution of Bcl‐2. These data suggest that the high constitutional level of Bcl‐2 may protect melanocytes from UVB‐induced injury, and that apoptotic death of melanocytes may be induced by the elevation and redistribution of Bax.
Colocalization of Dynactin Subunits P150Glued and P50 with Melanosomes in Normal Human Melanocytes
Authors: VANCOILLIE GARNET , LAMBERT JO , VANDER HAEGHEN YVES , WESTBROEK WENDY , MULDER AAT , KOERTEN HENK K. , MIEKE MOMMAAS A. , VAN OOSTVELDT PATRIC , NAEYAERT JEAN MARIE
Published: March 2003

Melanocytic dendrites consist of a central core of microtubules (MT) and a subcortical actin network. In previous reports we showed the presence of MT‐associated motor proteins kinesin and cytoplasmic dynein on the melanosomal surface, forming a link with MT (Vancoillie et al. J Invest Dermatol 2000;114:421–429; Vancoillie et al. Br J Dermatol 2000;143:258–306). We could also demonstrate the association of kinectin, the kinesin receptor, with melanosomes. The interaction of cytoplasmic dynein with its cargoes is thought to be indirectly mediated by dynactin, a complex that binds to the dynein intermediate chain. Therefore, in this study, we investigated the in vitro expression of dynactin subunits P150Glued and P50 in normal human epidermal melanocytes, keratinocytes, and dermal fibroblasts by reverse transcription‐polymerase chain reaction and northern blot analysis. In an attempt to gain an insight into the subcellular localization of dynactin, immunofluorescence and immunoelectron microscopy (IEM) studies were performed. The two isoforms of P150Glued and P50 are expressed in all studied skin cells. Immunofluorescence staining shows punctate distributions for P150Glued and P50 in melanocytes. P150Glued shows a clear centrosomal staining and accentuation in the dendrite tips. P50 is also accentuated in the perinuclear area and dendrite tips. Immunofluorescence double‐labeling with a melanosome marker showed apparent colocalization of both P150Glued and P50 with melanosomes. By IEM, P50 is detected on the surface of the majority of melanosomes in melanocytes. The colocalization of different subunits of the dynactin complex with melanosomes is consistent with the earlier finding of cytoplasmic dynein association with melanosomes and supports the hypothesis that this complex could form a link between cytoplasmic dynein and the melanosomal membrane.
Basic fibroblast growth factor suppresses tropoelastin gene expression in cultured human periodontal fibroblasts
Authors: Palmon A. , Roos H. , Reichenberg E. , Grosskop A. , Bar Kana I. , Pitaru S. , Redlich M.
Published: March 2003

Growth factors are known to play a major role in the regeneration of the periodontium. Basic fibroblast growth factor (bFGF) is a polypeptide growth factor considered to have a role in chemotaxis and mitogenesis of periodontal ligament (PDL) cells. The aim of this study was to assess the effect of bFGF on the transcription level of tropoelastin. As known controls, we assessed the transcription levels of collagen type I, collagen type III and the housekeeping gene, actin. Initially, PDL cells were cultured without bFGF for 3, 7 and 14 days. At each time point, total RNA was extracted and the levels of transcription were assessed by semiquantitative reverse transcription polymerase chain reaction (RT‐PCR) assay. The results showed that tropoelastin mRNA is transcribed in PDL cells and its levels increased from minimal amounts by day 3 to maximal amounts by day 14 of culture. We further examined the effect of the addition of 10 ng/ml bFGF to the culture media by day 14. The results showed that the addition of bFGF suppressed the transcription level of tropoelastin. At that time, as expected, a decrease in collagen type I transcription level was shown, while the transcription level of collagen type III was not affected. The findings that elastin is transcribed in vitro by PDL cells, but only negligibly in vivo, imply mechanisms that downregulate or even shut down the expression of the elastin gene in the functioning PDL. Basic FGF might be one of the cytokines involved in control of elastin expression in vivo.
Phenotypic comparison of periodontal ligament cells in vivo and in vitro
Authors: Lekic P. , Rojas J. , Birek C. , Tenenbaum H. , McCulloch C. A. G.
Published: March 2003

The mammalian periodontal ligament contains heterogeneous populations of connective tissue cells, the precise function of which is poorly understood. Despite close proximity to bone and the application of high amplitude physical forces, cells in the periodontal ligament (PL) are capable of expressing regulatory factors that maintain PL width during adult life. The study of PL homeostasis and PL cell differentiation requires culture and phenotypic methods for precise characterization of PL cell populations, in particular those cells with an inherently osteogenic program. Currently it is unknown if cells cultured from the PL are phenotypically similar to the parental cells that are present in the tissues. We have compared the phenotype of cells in vivo with cells derived from the PL and expanded in vitro to assess the general validity of in vitro models for the study of phenotypic regulation in vivo. Rat PL cells were isolated by either scraping the root of the extracted first mandibular molars (Group A), or by scraping the alveolar socket following extraction of first mandibular molars (Group B), or by obtaining a mixture of cells after disaggregating a block of tissue consisting of first mandibular molar, PL and the surrounding alveolar bone (Group C). Cultured cells at confluence were fixed and immunostained for α‐smooth muscle actin (α‐SMA), osteopontin (OPN), alkaline phosphatase (AP), or bone sialoprotein (BSP). For in vivo assessments, frontal sections of rat first mandibular molar were immunostained for α‐SMA, OPN, AP and BSP. We examined osteogenic differentiation of cultured PL cell cultures by bone nodule‐forming assays. In vivo and at all examined sites, >68% of PL cells were immunostained for AP; ∼50% and ∼51% for OPN and α‐SMA (p=0.3), respectively, while only ∼8% were positively stained for BSP (p<0.01). Analysis of cultured PL cells in Groups A, B and C showed 54%, 53% and 56% positive staining for α‐SMA respectively; 51%, 56%, 54% for OPN; 66%, 70%, 69% for AP and 2.2%, 1.4% and 2.8% for BSP. The mean percentage of PL cells in situ stained for the different markers was similar to that of cultured PL cells (Group A∼Group B∼Group C in situ for p>0.2) except for BSP which was 3 to 4 fold higher in vivo(p<0.01). PL cell cultures treated with dexamethasone showed mineralized tissue formation for all groups (A, B, C), but no mineralized tissue formation was detected in the absence of dexamethasone. As PL cells express quantitatively similar phenotypes in vitro and in vivo, we conclude that the in vitro models used here for assessment of PL cell differentiation appear to be appropriate and are independent of the cell sampling method. Further, dexamethasone‐dependent progenitors are present both on the root and bone‐related sides of the PL.
Expression of bone associated macromolecules by gingival and periodontal ligament fibroblasts
Authors: Ivanovski S. , Li H. , Haase H. R. , Bartold P. M.
Published: March 2003

The expression of hard tissue associated proteins may be used to identify periodontal fibroblasts with the capability to facilitate periodontal regeneration. The aim of this study was to describe, by immunohistochemistry, the distribution of osteocalcin, osteopontin, bone sialoprotein and bone morphogenic proteins‐2 and ‐4 (BMP‐2 and BMP‐4) within the human periodontium. Furthermore, the expression of mRNA for the above proteins and alkaline phosphatase by gingival and periodontal ligament fibroblasts in vitro was also assessed by reverse transcriptase polymerase chain reaction (RT‐PCR). Localization of osteopontin, osteocalcin, BMP‐2 and BMP‐4 within sections of human periodontal structures was stronger in the periodontal ligament compared to the gingiva. Bone sialoprotein was not detected in either of the soft tissues but, along with osteopontin and osteocalcin, it was localized in the cementum and bone. In vitro, both the gingival and periodontal ligament fibroblasts expressed mRNA for alkaline phosphatase, BMP‐2, BMP‐4 and osteopontin. Although there were no differences in the expression of alkaline phosphatase and BMP‐4 mRNA between the two cell types, we noted significantly higher mRNA levels of osteopontin in the periodontal ligament and BMP‐2 in the gingival fibroblasts. Osteocalcin and bone sialoprotein mRNA expression was only noted in the cultured periodontal ligament fibroblasts. From these results, it can be concluded that distinct differences exist between the two fibroblast populations in terms of the localization and mRNA expression of the majority of the hard tissue associated proteins. Furthermore, the elevated in vitro mRNA expression for osteocalcin, osteopontin and bone sialoprotein may be used to identify cells with the potential to facilitate hard tissue formation and hence periodontal regeneration.
Do interleukin‐1 polymorphisms predict the development of jreiodontitis or the success of dental implants?
Authors: Rogers Marina A. , Figliomeni Lisa , Baluchova Katarina , Tan Albert E. S. , Davies Gareth , Henry Patrick J. , Price Patricia
Published: March 2003

Factors which increase the risk of severe adult jreiodontitis (AP) may also contribute to the success of dental implants. To determine which cytokines may be relevant, levels of interleukin‐1α(IL‐1α), interleukin‐1β(IL‐1β), interleukin‐1 receptor antagonist (IL‐1ra), interleukin‐6 (IL‐6) and interferon‐γ(IFN‐γ) mRNA were quantitated in gingival tissue from jreiodontitis patients and healthy controls. Jreiodontitis significantly increased levels of IL‐1α, IL‐1β, IL‐6 and IFN‐γ mRNA relative to healthy tissues. IL‐1 was selected for further study, as it has inflammatory and bone resorbing projreties. We examined IL‐1A(−889) and IL‐1B(+3953) alleles in Caucasian patients with AP and early‐onset jreiodontitis (EOP), patients with dental implants and healthy individuals. The IL‐1B(+3953) polymorphism was associated with AP. This was evident from an increased homozygosity for allele 2 in patients with AP and a decreased heterozygosity in advanced AP patients. IL‐1A(−889) and a composite genotype [IL‐1A(−889)2 plus IL‐1B(+3953)2] showed no association with the incidence of jreiodontitis, disease onset or disease severity. IL‐1A(−889), IL‐1B(+3953) and the composite genotype also showed no association with failure of dental implants.
Participation of endogenous IGF‐I and TGF‐β1 with enamel matrix derivative‐stimulated cell growth in human periodontal ligament cells
Authors: Okubo K. , Kobayashi M. , Takiguchi T. , Takada T. , Ohazama A. , Okamatsu Y. , Hasegawa K.
Published: March 2003

Previous studies have provided the biological basis for the therapeutic use of enamel matrix derivative (EMD) at sites of periodontal regeneration. A purpose of this study is to determine effects of EMD on cell growth, osteoblastic differentiation and insulin‐like growth factor‐I (IGF‐I) and transforming growth factor‐β1 (TGF‐β1) production in human periodontal ligament cells (HPLC). We also examined participation of endogenous IGF‐I and TGF‐β1 with EMD‐stimulated cell growth in these cells. HPLCs used in this study were treated with EMD alone or in combination with antihuman IGF‐I antibody (anti‐hIGF‐I) or anti‐hTGF‐β1, recombinant human bone morphogenetic protein‐2 (rhBMP‐2), 1,25‐dihydroxyvitamin D3[1,25(OH)2D3], rhTGF‐β1 or rhIGF‐I. After each treatment, cell growth, the production of IGF‐I and TGF‐β1 and the expression of osteoblastic phenotypes were evaluated. EMD stimulated cell growth in dose‐dependent and time‐dependent manners. EMD was also stimulated to express IGF‐I and TGF‐β1 at protein and mRNA levels. The EMD‐stimulated cell growth was partially suppressed by cotreatment with anti‐hIGF‐I or anti‐hTGF‐β1, and cell growth was also stimulated by treatment with rhIGF‐I or rhTGF‐β1. rhBMP‐2 stimulated alkaline phosphatase (ALPase) activity and ALPase mRNA expression, and 1,25(OH)2D3 stimulated ALPase and osteocalcin mRNA expression. However, EMD showed no effect on the osteoblastic phenotypes expression. These results demonstrated that EMD has no appreciable effect on osteoblastic differentiation, however it stimulates cell growth and IGF‐I and TGF‐β1 production in HPLC, and that these endogenous growth factors partially relate to the EMD‐stimulated cell growth in HPLC.
Detection of Campylobacter rectus in periodontitis sites by monoclonal antibodies
Authors: Ihara Hideaki , Miura Tadashi , Kato Tetsuo , Ishihara Kazuyuki , Nakagawa Taneaki , Yamada Satoru , Okuda Katsuji
Published: March 2003

Campylobacter rectus, a gram‐negative, microaerophilic, and motile bacterium, has been proposed to play a pathogenic role in human periodontitis. Surface components, such as the flagellum, surface layer (S‐layer), and cytotoxin, have been reported as possible virulence factors of the microorganism. In the present study, monoclonal antibodies against surface components of this bacterium were produced to detect and investigate the pathogenic potential of C. rectus in periodontitis. Two monoclonal antibodies, designated CRT‐1 and CRT‐2, recognized a peculiar 150 kDa S‐layer protein by immunoblot analysis. The CRT‐2 antibody reacted to all C. rectus strains tested, except for the S‐layer negative strain of the species [C. rectus ATCC 33238 S‐layer (–) strain]. The CRT‐3 antibody reacted to a 60‐kDa protein in C. rectus and also cross‐reacted with Campylobacter showae ATCC 51164 and CCUG 11641 strains. Using the dot‐blot method, we were able to detect C. rectus using the CRT‐2 antibody when as few as 103 organisms were present in a subgingival dental plaque sample. Detection of C. rectus in plaque samples correlated significantly with clinical findings such as probing depth (P < 0.001), bleeding on probing (P < 0.001), and gingival index (P < 0.001). These findings indicate that infection by C. rectus may be an important indicator of periodontal disease status.
Comparative quantitative analysis of ultraviolet B‐induced skin blood flow change using laser Doppler perfusion imaging technique
Authors: Youn J.‐I. , Park S.‐B. , Park B.‐S. , Han W.‐S.
Published: March 2003

Laser Doppler perfusion imaging (LDI), recently developed, can generate a color‐coded image of tissue perfusion, making it possible to assess the spatial distribution of skin perfusion without touching the surface. Using this apparatus, we investigated ultraviolet B (UVB)‐induced perfusion profile of the skin and compared the results with those obtained from laser Doppler flowmetry (LDF). Fifteen adult male Korean volunteers were irradiated with several doses of UVB ranging from 25 mJ/cm2 to 186 mJ/cm2. Twenty‐four hours later, the erythema reaction was evaluated with LDF and LDI systems. There was a significant correlation between the logarithmic dose of UVB and erythema values. The curves consisted of two parts, an initial, flat phase and then a linear, steep one. Also, there was a good correlation between LDF and LDI. The LDI is as sensitive as conventional LDF, but has the many advantages of measuring blood flow over large areas without contact with the skin surface. This instrument will be useful in the measurement of skin blood flow in many areas of dermatological application.
p53, cyclin‐D1, PCNA, AgNOR expression in squamous cell cancer of the lip: a multicenter study
Authors: Fabbrocini G. , Russo N. , Pagliuca M. C. , Delfino M. , Staibano S. , Molea G. , Mancini A. , Virgili A. , Valente M. G. , Bratina G. , Galbiati S. , Marzaduri A. , Orlandi K. , Bottoni U. , Calvieri S. , Landro A. , Cainelli T. , Delfino S. , Rosa G.
Published: March 2003

Background: The development of squamous cell carcinoma of the lower lip is an interesting model of photocarcinogenesis because of the structural and topographic characteristics of the lips. The purpose of this study was to evaluate the expression of immunohistochemical markers on the lips of patients with lower lip squamous cell carcinoma (LLSCC), compared with a control population.

Methods: Of the 98 subjects involved in the study, 58 were suffering from squamous cell carcinoma of the lower lip. The remaining 40 acted as a control. The case studies were taken from six university and hospital dermatology and plastic surgery departments. Questionnaires were administered to assess the risk factors for LLSCC. The cases involving squamous cell carcinoma underwent surgical excision and punch biopsy specimens were obtained from 20 control patients. Tissues were prepared in 5‐μm‐thick sections to carry out the following immunohistochemical study: PCNA, p53, AgNOR, cyclin‐D1, bcl‐2.

Results: The lower lip was the predominant location of squamous cell carcinoma, with the following factors playing important roles: chronic sun exposure, history of smoking, alcohol use and familial risk of cutaneous tumors. The male/female ratio in our survey was 5:1. The p53 protein was positive in approximately 50% of SCC cases and in 20% of controls. This protein is mostly associated with chronically photoexposed skin areas. AgNOR positivity increased with the loss of cellular differentiation; a progressive increase in size and a poorly defined shape were evident in poorly differentiated carcinomas.

Conclusions: The results of this multicenter study showed that there is a noticeable difference in the expression of PCNA, p53, cyclin‐D1, and AgNOR in tissues from patients with LLSCC and controls.
Evaluation of the capacity of sunscreens to photoprotect lupus erythematosus patients by employing the photoprovocation test
Authors: Stege H. , Budde M.‐A. , Grether‐Beck S. , Krutmann J.
Published: March 2003

Although sunscreens are widely used to photoprotect patients with photosensitive lupus erythematosus (LE), standardized controlled studies that can prove their efficacy for this indication have been lacking. Therefore, in the present study, the capacity of three different, commercially available sunscreens to prevent the development of skin lesions that have been induced in LE patients under standardized, reproducible conditions by employing a provocative phototest was assessed. In a double blind, intraindividual comparative study, 11 patients with LE were photoprovoked according to a standard protocol. All patients developed LE‐specific skin lesions upon photoprovocation with a combination of UVA plus UVB radiation. Each of the sunscreens tested prevented the development of skin lesions in this assay, but to various extents. Suncreen A (UVB: Octocrylene; UVA: Mexoryl SX, Mexoryl XL, Parsol 1789; TiO2) was by far the most effective by protecting in 11/11 patients. This protective capacity was corroborated by studies in which strong ICAM‐1 mRNA expression was found in unprotected test areas, but not in sunscreen A pretreated sites. In contrast to sunscreen A, sunscreen B (UVB: Eusolex 6300, Parsol MCX, Uvinul T150, Neohelipan; UVA: Parsol 1789; TiO2) protected in 5 patients and sunscreen C (Eusolex 6300, Parsol MCX, Uvinul T150; UVA: Parsol 1789; TiO2) in 3 out of 11 patients. These studies indicate that the use of sunscreens is beneficial to LE patients because it can prevent the development of UV radiation‐induced skin lesions. Effective protection, however, might vary considerably between different sunscreens.
Erythropoietic protoporphyria (EPP) at 40. Where are we now?
Authors: Sarkany R. P. E.
Published: March 2003

Since Professor Magnus first defined erythropoietic protoporphyria (EPP) in 1961, there has been considerable progress in the understanding this disease. The past decade has been a period of spectacular progress in understanding the genetics and pathogenesis of the disease by molecular investigation. However, progress in therapy for EPP has been slower, and has been dogged by difficulty in assessing treatment efficacy in patients. We are now entering an era in which advances in molecular genetics are directly affecting patient management. This review summarises laboratory and clinical progress in EPP in the past 40 years, and assesses the potential impact of molecular biology on clinical practice.
Quantitative assessment of narrow‐band UVB induced tanning during phototherapy in Korea
Authors: Choe Y. B. , Rim J. H. , Youn J. I.
Published: March 2003

Background/Purpose: Narrow‐band (TL‐01) UVB lamps are being increasingly used for phototherapy of psoriasis and other dermatoses, for their excellent effect compared with broad‐band UVB sources. Many patients receiving phototherapy have complained about the tanning effect of ultraviolet radiation especially in dark‐skinned ones. So we wished to know the degree of pigmentation induced by phototherapy during narrow‐band UVB treatment.

Methods: A total of 20 psoriasis patients receiving narrow‐band UVB phototherapy were included in this study. A Minolta spectrophotometer CM‐2002 was used to measure pigmentation. All patients were evaluated for skin color every seventh day for 7 weeks. The L* value (luminance) gives information about the relative lightness ranging from total black to pure white. The a* value represents the balance between red and green, and the b* value between yellow and blue.

Results: The L* values which indicate luminance decreased continuously until the 5th week, when maximum tanning was obtained. Afterwards minimal change was observed until the 7th week. The change of a* and b* values also showed the pattern that was compatible with the above results. The mean individual typology angle of our subjects was 41.9°, which indicated they fell into ‘light’ group of constitutional skin color category.

Conclusion: From this study, we found that pigmentation induced by narrow‐band UVB phototherapy increased continuously until the 5th week and then did not progress. Our results provide standard data of skin pigmentation during narrow‐band UVB phototherapy in Korean brown skin.
Time course of ultraviolet‐induced skin reactions evaluated by two different reflectance spectrophotometers: DermaSpectrophotometer® and Minolta spectrophotometer CM‐2002®
Authors: Park Seok‐Beom , Huh Chang‐Hun , Choe Yong‐Beom , Youn Jai‐Il
Published: March 2003

Backgrounds: Many attempts have been made to quantify ultraviolet (UV)‐induced erythema and pigmentation, but most studies have been focused on the initial changes of reaction for a few hours or days and neglected the later events.

Methods: A time course of skin colour changes induced by fluorescent sunlamp with a broad band of UVA and UVB radiation was evaluated in 15 Korean male volunteers using two different reflectance spectrophotometers for 28 days. The results were presented by E (erythema)‐ and M (melanin)‐index as well as values converted to the L*a*b* system recommended by the CIE (Commission Internationale de l'Eclairage).

Results: The mean individual typology angle of the subjects was 46.6°, which indicated ‘light’ group in constitutional skin colour category. A day after UV exposure, the L* and b* values decreased significantly, following the colour direction of persistent pigment darkening. The values went in the opposite direction persistently until after the 1st week, when maximum tanning was obtained. They then shifted toward their original positions, parallel to the constitutive melanization axis. The a* index showed a significant increase toward the mean colour of haemoglobin on day 1. It returned to its original value along the constitutive melanization axis. The E‐index showed a maximum value at day 1, then returned to baseline. The value of M‐index reached a peak at day 7. There was no significant difference between the two instruments, but each has its own characteristic features.

Conclusion: These promising quantitative methods should enable us to achieve objective measurement of the dermatophysiologic changes and to evaluate the efficacy of therapeutic modalities on skin disorders without the inherent errors associated with subjective judgement. Our results provide standard data on a time course of UV‐induced skin erythema and pigmentation.
Use of human reconstituted epidermis Episkin® for assessment of weak phototoxic potential of chemical compounds
Authors: Portes P. , Pygmalion M. J. , Popovic E. , Cottin M. , Mariani M.
Published: March 2003

Background/purpose: Drug‐induced phototoxicity is a non‐immunological inflammatory skin reaction, caused by concurrent topical or systemic exposure to a specific molecule and ultraviolet radiation. Most of phototoxic compounds absorb energy particularly from UVA light leading to activated derivatives, which can induce cellular damage. This type of adverse cutaneous response can be reproduced, in vitro, using human skin models. In this study, we investigated the ability of human reconstituted epidermis Episkin® to assess skin phototoxicity of weak phototoxic compounds such as 6‐methylcoumarin and ofloxacin, compared to a strong one, chlorpromazine, and two negative controls (sodium dodecyl sulphate (SDS), sulisobenzone).

Methods: After 1 h incubation with five test concentrations of each chemical compound, epidermis was then exposed or not to UVA at a non‐cytotoxic dose (50 J/cm2). 18 h after UVA exposure, cellular damage was evaluated measuring cytotoxicity by MTT conversion test; in addition, pro‐inflammatory mediator IL‐1α release was also investigated.

Results: Topical pretreatment of Episkin®, with weak phototoxic compounds induced, after UVA exposure, a dose‐dependent decrease in cell viability, in concordance with an increasing IL‐1α release. Moreover, compared to chlorpromazine, the lower IL‐1α release observed with 6‐methylcoumarin and ofloxacin could be linked to their weak phototoxic potential.

Conclusion: Human reconstituted epidermis Episkin® can be useful to study in vitro the onset of cutaneous phototoxic reactions and particularly to identify weak phototoxic compounds.
014 In‐vivo determination of UVA sunscreen efficacy using diffuse reflectance spectroscopy
Authors: Moyal D. , Chardon A.
Published: March 2003

A variety of in vitro and in vivo methods have been proposed to evaluate the UVA efficacy of sunscreens. Diffuse reflectance spectroscopy (DRS) is a recent approach that allows measuring sunscreen protectiveness in the UVA portion of the spectrum. FDA representatives have shown a marked interest for the development of this alternative method. The absorption spectrum of the product is obtained by measuring the change in skin reflection due to the product. From this absorption spectrum the UVA efficacy of a sunscreen product can then be calculated for an appropriate UV source and a given skin response action spectrum. One major advantage of this test method is that the UVA protection is determined directly on human skin, thus accounting for sunscreen/skin surface and emulsion interactions encountered in vivo, but not in vitro.

Both DRS and in vivo persistent pigment darkening (PPD) method were used to compare the UVA efficacy of various UVA sunscreens (such as oxybenzone, avobenzone, ecamsule and zinc oxide at different concentrations) and of marketed products. A significant correlation was found between DRS and PPD results only for photostable products. To get a correlation with PPD results with photo‐unstable products, a pre‐exposure of the products applied on skin was found necessary before performing the DRS measurements.

The DRS method allows evaluating both the UVA absorption spectrum of the products and their broadness of absorption and can thus be considered as a powerful tool for the in‐vivo evaluation of sunscreen UVA protective efficacy.
019 The COLIPA Standard for solar simulators failed to standardize sunscreen SPFS
Authors: Sayre R.M.
Published: March 2003

The COLIPA Standard for solar simulators was developed to insure that SPF tested in different laboratories was not different because of the solar simulator used. Indeed for products with lower SPFs 2‐10, the solar simulator standard reasonably assures similar SPFs when tested in different laboratories. For products with SPFs greater than 15, the SPF for the same product could be tested at 15 in one laboratory but as an SPF 100 in another.

Differences in SPF due to solar simulator filtration will occur only for sunscreen products that exhibit absorption like cut‐off filters. Products which generally absorb all UV wavelengths equally will not exhibit differences in SPF due to solar simulator filtration.

In addition because of different amounts of UVA allowed within the COLIPA standard, the actual response for a given exposure may in one laboratory produce persistent pigment darkening and in another a simple sunburn. Ways to correct this flaw will be examined.
003 UVB dose and cell cycle conditions influence the outcome of UVB‐induced HIV activation
Authors: Breuer‐Nicham J. , Cruz P. D. , Zhang C. L. , Actor J. , Lewis D. E. , Duvic M.
Published: March 2003

Having reported previously that suberythmogenic doses of UVB activate HIV in human skin as shown by a 6–10 fold rise in HIV‐1 gag, gene by RT‐PCR and similar increments in HIV+ lymphocytes and dendritic cells by RT‐PCR‐ISH, we dissected the mechanisms underlying these events. Thus, we examined effects of UVB (0–200 J/m2) on HIV transcription, cell cycle distribution, and apoptosis on two Jurkat cell lines (1G5 and DC10). 1G5 and DC10 lines are identical in bearing the HIV‐LTR‐driven luciferase (Luc) gene, but with the latter also carrying the tat gene. Whereas lower doses of UVB (up to 50 J/m2 induced Luc expression in a UVB dose‐dependent manner in DC10 cells and G2/M arrest of these cells, it produced only minimal Luc expression in 1G5 cells with no cell cycle arrest noted. By contrast. higher doses of UVB (100–200 J/m2) led to reduced Luc expression and to apoptosis in DC10 cells, but not in 1G5 cells. Our results are consistent with the concept that activation of the HIV promoter by UVB is dependent on tat. The G2/M arrest induced by lower‐dose UVB may allow accumulation of HIV in activated lvmphoeytes; DNA repair may complete the cell cycle leading to proliferation of HIV+ cells. Apoptosis induced by higher‐dose UVB reduced HIV transcription, but may also release viral particles from dying cells. These findings indicate that even small increments within a subelythmogenic UVB dose range can have a dramatic impact on HIV transcription, that in turn may be related to altered cell cycle programs. Thus, the precise UVB dose and other inter‐current skin conditions affecting cell cycles (e.g., medications, diseases and infections other than HIV) at the time of UVB exposure may influence the net outcome of HIV activation in skin.
008 The time‐course of TL‐01 UVB erythema
Authors: Man I. , Dawe R.S. , Ferguson J. , Ibbotson S.H.
Published: March 2003

We examined the characteristics of TL‐01 UVB erythema and determined the optimal starting dose prior to TL‐01 phototherapy, Twenty‐eight subjects were recruited. Eight test sites on each subject's back were irradiated with a TL‐01 dose series (50‐550 mJ/cm2). Erythema was recorded visually and with a reflectance device at 4, 8, 12, 24, 48 and 72 h in 19 subjects and at 12, 15, 18, 21 and 24 h in nine subjects. Dose‐response curves were constructed and the D0.025 (equivalent to the visual minimal erythema dose [MED]) and the maximum slope determined.

Erythema was evident at 4 h in the 19 subjects tested. The lowest median MED occurred at 12 h (170 mJ/cm2) and this was significantly lower that at 24 h (median 200 mJ/cm2; P = 0.019). the majority of subjects were at maximal erythema at 12 h (22/28) and 15 h (8/9). MED reading at 24 h (MED24 h) would miss peak erythema in 15/28 subjects. If, as is commonly practiced, 70% of the MED24 h was given, 10/28 subjects would have received a first treatment dose that would be equal to or exceed the lowest MED. If 50% of the MED24 h was given, only 2/28 would develop erythema (P = 0.0078, 95% Cl [10‐46.5%]). From the dose‐response data, D0.025 at 12 h was significantly lower than at 24 h (P = 0.0019). The slope of the erythemal dose‐response curve remained constant from 8 to 48 h. Maximal TL‐01 UVB erythema occurs at 12 h. Our data suggest that the optimal first TL‐01 treatment dose is 50% of the MED24 h.
Melatonin increases activities of glutathione peroxidase and superoxide dismutase in fetal rat brain
Authors: Okatani Yuji , Wakatsuki Akihiko , Kaneda Chitose
Published: March 2003

Melatonin is a powerful scavenger of oxygen free radicals. In humans, melatonin is rapidly transferred from the maternal to the fetal circulation. To investigate whether or not maternal melatonin administration can protect the fetal rat brain from radical‐induced damage by increasing the activities of antioxidant enzymes, we administered melatonin to pregnant rats on day 20 of gestation. Melatonin (10 mg/kg) was injected intraperitoneally at daytime (14:00 hr) and, to remove the fetuses, a laparotomy was performed at 1, 2, or 3 hr after its administration. We measured the melatonin concentration in the maternal serum and in fetal brain homogenates and determined the activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH‐Px) in fetal brain homogenates. Melatonin administration markedly increased melatonin concentrations in the maternal serum and fetal brain homogenates, with peak levels achieved 1 hr after melatonin administration (serum: 538.2±160.7 pM/mL; brain homogenates: 13.8±2.8 pM/mg protein). Between 1 and 3 hr after melatonin administration, GSH‐Px activity in fetal brain homogenates increased significantly (P<0.01). Similarly, SOD activity increased significantly
between 1 and 2 hr after melatonin administration (P<0.01). These results indicate that melatonin administration to the mother increases antioxidant enzyme activities in the fetal brain and may thereby provide indirect protection against free radical injury. Thus, melatonin may potentially be useful in the treatment of neurodegenerative conditions that may involve excessive free radical production, such as fetal hypoxia and preeclampsia.
Salivary melatonin response to acute pain stimuli
Authors: Nelson F.A. , Farr L.A. , Ebadi M.
Published: March 2003

Evidence for a relationship between melatonin, nociception, and analgesia in humans is based on data that are only linked by association and simultaneous occurrence. Studies have reported inverse correlation of the circadian melatonin rhythm with nociception latency and enhancement of opioid analgesia by simultaneous administration of melatonin in animals. This study examines the response of salivary melatonin to acute pain stimuli in 18 healthy subjects ranging in age from 19 to 50 years. A biphasic melatonin response following an acute pain stimulus of 36 V was observed, F(8, 8)=17.839, P<0.001. Within 5 min of the stimulus, melatonin decreased and reached a plateau of 36 pg/mL below baseline by 20 min. This decrease was followed by an increase of 5 pg/mL. Melatonin levels subsequently decreased until they had reached levels similar to those anticipated for the time of day and did not vary thereafter. The magnitude of the melatonin response was not related to age or gender. There was no association between voltage and magnitude of the melatonin responses observed at 15 min (r=0.185, P=0.51) or at 30 min (r=0.468, P=0.09). This study provides the first evidence of melatonin utilization and subsequent pineal gland synthesis following acute pain episodes in humans.
Presence of oxytocinergic neuronal‐like cells in the bovine pineal gland: an immunocytochemical and in situ hybridization study
Authors: Badiu Corin , Badiu Liliana , Coculescu Mihail , Vilhardt Hans , Møller Morten
Published: March 2003

In the last decade, there is more and more evidence showing the role of the central innervation of the pineal gland, but there are controversies around the intra or extrapineal origin of oxytocin found within the pineal tissue. In order to check the amount and the site of synthesis of oxytocin in the bovine pineal gland, we performed a morphological and chromatographic study. The anatomical distribution of the pineal oxytocin was explored by immunohistochemistry and in situ hybridization for the corresponding mRNA. The results confirm the presence of oxytocinergic fibres in the bovine pineal, some of them endowed with big varicosities. Immunohistochemistry also displayed neuronal‐like cells in the pineal body. The in situ hybridization for the mRNA encoding pre‐pro/oxytocin‐NFZ I used a mixture of three oligonucleotide probes labelled with 35S. This allowed identification of positive cells in the bovine pineal. The content in oxytocin was evaluated by radioimmunoassay during 5 months, from July to November, and the peptidic extract revealed an increase of pineal oxytocin immunoreactivity in September as compared with July or November. The significance of intrinsic oxytocin innervation of the bovine pineal gland, as well as the threefold increase of the oxytocin content in the pineal in September, remains to be elucidated.
Increased melatonin 1a‐receptor immunoreactivity in the hippocampus of Alzheimer's disease patients
Authors: Savaskan Egemen , Olivieri Gianfranco , Meier Fides , Brydon Lena , Jockers Ralf , Ravid Rivka , Wirz‐Justice Anna , Müller‐Spahn Franz
Published: March 2003

The pineal secretory product melatonin has, in addition to regulating retinal, circadian and vascular functions, neuroprotective effects. Blood melatonin levels are often decreased in Alzheimer's disease (AD), a progressively disabling neurodegenerative disorder. In this study we provide the first immunohistochemical evidence for the localization of melatonin 1a‐receptor (MT1) in aged human hippocampus and a comparison of AD cases. MT1 was localized to pyramidal neurons in the hippocampal cornu ammonis (CA)1‐4 subfields. There was a distinct increase in staining intensity in all AD cases indicating an up‐regulation of the receptor, possibly as a compensatory response to impaired melatonin levels in order to augment melatonin's neuroprotective effects.
No evidence for a phase delay in human circadian rhythms after a single morning melatonin administration
Authors: Wirz‐Justice Anna , Werth Esther , Renz Claudia , Müller Simon , Kräuchi Kurt
Published: March 2003

Although there is good consensus that a single administration of melatonin in the early evening can phase advance human circadian rhythms, the evidence for phase delay shifts to a single melatonin stimulus given in the early morning is sparse. We therefore carried out a double‐blind randomized‐order placebo‐controlled study under modified constant routine (CR) conditions (58 hr bedrest under ˜8 lux with sleep 23:00–07:00 hr) in nine healthy young men. A single (pharmacological) dose of melatonin (5 mg p.o.) or a placebo was administered at 07:00 hr on the first morning. Core body temperature (CBT) and heart rate (HR) were continuously recorded, and saliva was collected half‐hourly for assay of melatonin. Neither the timing of the mid‐range crossing times of temperature (MRCT) and HR rhythms, nor dim light melatonin onset (DLMOn) or offset (DLMOff) were phase shifted the day after melatonin administration compared with placebo. The only change was an altered wave form of the CBT rhythm: longer duration of higher‐than‐average temperature after melatonin administration. Under the same modified CR conditions we have previously demonstrated a clear phase advance of the above circadian rhythms following a single administration of 5 mg melatonin in the evening. This study's failure to find significant delays to a single administration does not negate other positive findings with multiple doses, which may be necessary for a `weak zeitgeber'.