bluuebunny/crossref_metadata_2025_split huggingface dataset:
Tyrosinase Gene Expression in Human Tissues
Authors: ABATTYANI ZIT , XERRI LUC , HASSOUN JACQUES , BONERANDI JEAN‐JACQUES , GROB JEAN‐JACQUES 
Published: July 2006

The occasional occurrence of primary extra‐cutaneous malignant melanomas (MM) has led to the hypothesis that melanocytes derived from the neural crest may be arrested in their migration and may undergo an in situ malignant transformation. However, aggregates of nevus cells have only rarely been identified by histological examination in a few organs other than skin and eye. Tyrosinase is a melanin biosynthetic enzyme that is considered one of the most specific markers of melanocytic differentiation. We have at‐tempted to detect cells committed to the melanocytic lineage, in human tissues, by means of tyrosinase gene expression. Total RNA was extracted from normal and neoplastic tissues and analyzed using a highly sensitive reverse transcription PCR assay with primers specific for the tyrosinase gene. Peripheral blood mononuclear cells (PBMC) from healthy subjects were used as negative controls. Tyrosinase transcripts were identified in a wide range of normal organs such as skin, lymph nodes, antrum, colon, kidney, lung, testis, ovary, breast, and peripheral nerve. Tyrosinase RNA was also detected in neoplastic samples including benign cutaneous nevi, lymph nodes involved by MM, breast carcinoma, liposarcoma, malignant lymphoma, and schwannoma. PBMC from patients with meta‐static MM were also positive, while no positivity was detected in blood specimens from patients with other cancers.Therefore, it appears likely that cells expressing the tyrosinase gene are present in a wide range of human tissues. Although these cells still have to be accurately identified, one could propose that they might correspond to either fully differentiated melanocytes, melanocytic precursors, or Schwann cells bearing potentialities of melanocytic differentiation. Occurrence of at least some cases of primary extra‐cutaneous MM may be ascribed to any one of these possibilities.
Regulation of Melanogenesis Induced by 5‐Methoxypsoralen Without Ultraviolet Light in Murine Melanoma Cells
Authors: MENGEAUD VALÉRIE , ORTONNE JEAN PAUL 
Published: July 2006

Melanogenesis in melanoma cells can be enhanced by psoralens in the absence of UV light. Melanin biosynthesis is regulated by a number of melanocyte‐specific proteins, including tyrosinase, DOPAchrome tautomerase (DCT), and tyrosinase‐related protein‐1 (TRP‐1, gp75). To get more insight on the molecular mechanisms involved in psoralens‐induced melanogenesis, we determined tyrosinase and DCT activities as well as mRNA and protein levels of tyrosinase, DCT, and TRP‐1 in S91 mouse melanoma cells treated by 5‐MOP. High concentration of 5‐MOP (5 × 10‐5 M) induced a time‐dependent increase of tyrosinase activity and melanin content, which was correlated to an increase of both mRNA and protein levels of tyrosinase. These results demonstrate that the 5‐MOP stimulation of melanogenesis is related to increased tyrosinase synthesis. In addition, 5‐MOP stimulated TRP‐1 synthesis and induced a dose‐dependent decrease of DCT activity without any modification in the expression of the protein.We explored then the signalling pathways involved in 5‐MOP‐induced melanogenesis and, particularly, the role of cyclic AMP and protein kinase C (PKC). A small stimulation of cyclic AMP production was observed in presence of 5‐MOP. Furthermore, 1‐oleoyl‐2‐acetylglycerol (OAG), a PKC activator, potentiated the 5‐MOP stimulation of tyrosinase activity, while calphostin, a specific PKC inhibitor, inhibited the 5‐MOP induction of tyrosinase activity. Phorbol‐myristate acetate (PMA), described as a strong activator of PKC, inhibited also the effect of 5‐MOP when used at long term.Taken together, these results demonstrate that in murine melanoma cells 5‐MOP stimulates melanogenesis by increasing activity and synthesis of tyrosinase. Tyrosinase and TRP‐1 expression are coordinately regulated by 5‐MOP Furthermore, a negative correlation between melanogenesis and DCT activity was observed under 5‐MOP stimulation. At least, PKA and PKC systems appear to play an important role in the melanogenic effect of 5‐MOP.
Keratinocyte Extracellular Matrix‐Mediated Regulation of Normal Human Melanocyte Functions
Authors: NAKAZAWA KEIKO , NAKAZAWA HISAYOSHI , COLLOMBEL CHRISTIAN , DAMOUR ODILE 
Published: July 2006

Active roles of cell‐cell interaction between melanocytes and neighboring keratinocytes for the regulation of melanocyte functions in the skin have been suggested. We examined substantial regulatory mechanisms of keratinocyte extracellular matrix (kECMs) for normal human melanocyte functions without direct cell‐cell contact. We specially devised kECMs from proliferating or differentiating keratinocytes and further treated them with environmental stimulus ultraviolet B (UVB) for skin pigmentary system. Normal human melanocytes (NHM) were cultured on the various keratinocyte ECMs and initially the effects of the kECMs upon melanocyte morphology (dendrite formation and extension), growth, melanin production and expressions of pigmentation‐associated protein (MEL‐5) and proliferation‐associated protein (proliferating cell nuclear antigen; PCNA/cyclin) were studied. Then we compared the effects of these cell‐matrix interactions with those of direct melanocyte‐keratinocyte, cell‐cell contact in co‐culture on melanocyte functions.Melanocytes cultured on any types of the kECMs that were tested significantly extended dendrites more than that on plastic cell culture dish without kECM (control). Melanocytes cultured on the kECM prepared from UVB irradiated differentiating keratinocytes resulted in 219% increase in the number of dendrites. The growth of melanocytes on kECMs was also stimulated up to 280% of control. The kECM produced by proliferating keratinocytes had a more significant effect on the growth than kECM from differentiating keratinocytes. This melanocyte growth stimulating effect was decreased with kECM from UVB treated differentiating keratinocytes. The melanin content per melanocyte was constant on any of the kECMs. Expression of pigmentation‐associated protein detected by monoclonal antibody, MEL‐5, was not changed on the kECM, while it was increased in melanocytes in co‐culture with keratinocytes. Expression of PCNA/cyclin in melanocytes cultured on kECMs was generally downregulated on kECM and in co‐culture compared to that in a control culture.We demonstrated that the kECMs play important roles in the melanocyte morphology and proliferation. These observations suggest that environmental (UVB) and physiological (Ca++) stimuli can regulate melanocyte functions through the keratinocyte extracellular matrix in vivo.
Characterization of Vitiligo Antigens
Authors: CUI JIAN , ARITA YUKO , BYSTRYN JEAN‐CLAUDE 
Published: July 2006

Patients with vitiligo have circulating antibodies directed in part to pigment cell antigens with MWs of approximately 90, 75, and 40‐45 kDs. These antigens are denominated VIT 90, VIT 75, and VIT 40, respectively. To further characterize these “vitiligo” antigens, we examined their relation to antigens defined by a panel of 25 monoclonal antibodies (moab) to pigment cell antigens. We found by immunoprecipitation and SDS‐PAGE analysis of 125I labelled, detergent soluble, human melanocyte macromolecules, that 24 (83%) of 29 patients with vitiligo had antibodies to one or more vitiligo antigens vs. 2 (7%) of 28 control individuals. Seventeen of the 25 moabs did not react with any labelled antigen in the same lysate. Of the remaining eight moabs, only four precipitated an antigen that co‐migrated with one of the vitiligo antigens. Moab TA99, HMSA‐5, and TMH‐1 (all directed to the 75 kD tyrosinase‐related protein [TRP1]) co‐migrated with VIT 75. Moab W6/32 (directed to class I HLA antigen) co‐migrated with VIT 40. Immunodepletion studies with vitiligo antibodies selectively depleted the antigen defined by W6/32 but not the antigen defined by TA99 and HMSA‐5, indicating that VIT 75 was not the 75 kD tyrosinase‐related protein. The vitiligo antigens were easily labelled by the lactoperoxidase technique but poorly labelled with 35S‐methionine, suggesting they are expressed on the cell surface.These studies indicate that VIT 90 and VIT 75 differ from antigens defined by currently available moabs to pigment cell antigens. VIT 40 appears to share a cross‐reactive epitope, or be tightly bound to, class I HLA antigen.
The Effect of Ultraviolet B Induced Adult T Cell Leukemia‐Derived Factor/Thioredoxin (ADF/TRX) on Survival and Growth of Human Melanocytes
Authors: FUNASAKA YOKO , ICHIHASHI MASAMITSU 
Published: July 2006

Ultraviolet B (UVB) radiation is known to induce reactive oxygen species (ROS) in the skin. The skin, however, counteracts ROS by both constitutional and newly produced antioxidants. One such antioxidant, adult T cell leukemia‐derived factor (ADF), a human homologue of thioredoxin (TRX), was shown to be efficiently produced in and released from cultured normal human keratinocytes after UVB irradiation by Northern and Western blot analyses and enzyme‐linked immunoabsorbent assay (ELISA). Recombinant ADF (rADF) did not rescue UVB‐induced melanocyte death, either when added pre‐ or post‐UV irradiation. However, further addition of neutralizing antibody caused cell death of both keratinocytes and melanocytes. rADF was shown to induce higher expression in melanocortin‐1 receptor (MC1‐R) mRNA accompanied by increased binding activity using 125I labeled [Nle4, D‐Phe7]‐α‐MSH in melanocytes, leading to the enhanced increment of DNA synthesis.Taken together, it was shown that released ADF from UVB‐irradiated keratinocytes acts as a survival factor for both keratinocytes and melanocytes but does not rescue UV‐induced melanocyte death. Further, it may work as one of the stimulatory factors for UVB‐induced melanogenesis by upregulating MSH‐R binding activity in combination with the enhanced DNA synthesis by α‐MSH.
Modeling Drug‐Melanin Interaction With Theoretical Linear Solvation Energy Relationships
Authors: LOWREY ALFRED H. , FAMEINI GEORGE R. , LOUMBEV VALERY , WILSON LELAND Y. , TOSK JEFFREY M. 
Published: July 2006

The affinity of drugs and other xenobiotic agents for melanin is a well‐known phenomenon, often occurring with serious physiological consequences. For example, the interaction of anti‐psychotic drugs with neuromelanin may play a pivotal role in the induction of extrapyramidal movement disorders associated with the chronic administration of phenothiazine and other neuroleptic agents. Little, however, is known about the complete nature of melanin‐drug binding and the impact of these interactions on the physicochemical properties of melanin.Data, such as binding affinities, can be analyzed using recently developed computational methods that combine mathematical models of chemical structure with statistical analysis. In particular, theoretical linear solvation energy relationships provide a convenient model for understanding and predicting biological, chemical, and physical properties.By using this modeling technique, drug‐melanin binding of a set of 16 compounds has been analyzed with correlation analysis and a set of theoretical molecular parameters in order to better understand and characterize drug‐melanin interactions. The resulting correlation equation supports a charge transfer model for drug‐melanin complex formation and can also be used to estimate binding constants for related compounds.
The Inhibitory Effect of Glabridin from Licorice Extracts on Melanogenesis and Inflammation
Authors: YOKOTA TOMOHIRO , NISHIO HIROYUKI , KUBOTA YASUO , MIZOGUCHI MASAKO 
Published: July 2006

Glabridin is the main ingredient in hydrophobia fraction of licorice extract affecting on skins. In this study, we investigated inhibitory effects of glabridin on melanogenesis and inflammation using cultured B16 murine melanoma cells and guinea pig skins. The results indicated that glabridin inhibits tyrosinase activity of these cells at concentrations of 0.1 to 1.0 μg/ml and had no detectable effect on their DNA synthesis. Combined analysis of SDS‐polyacrylamide gel electrophoresis and DOPA staining on the large granule fraction of these cells disclosed that glabridin decreased specifically the activities of Tl and T3 tyrosinase isozymes.It was also shown that UVB‐induced pigmentation and erythema in the skins of guinea pigs were inhibited by topical applications of 0.5% glabridin. Anti‐inflammatory effects of glabridin in vitro were also shown by its inhibition of superoxide anion productions and cyclooxygenase activities. These data indicated that glabridin is a unique compound possessing more than one function; not only the inhibition of melanogenesis but also the inhibition of inflammation in the skins.By replacing each of hydroxyl groups of glabridin with others, it was revealed that the inhibitory effect of 2′‐O‐ethyl glabridin was significantly stronger than that of 4′‐O‐ethyl‐glabridin on melanin synthesis in cultured B16 cells at the concentration of 1.0 mg/inl. With replacement of both of two hydroxyl groups, the inhibitory effect was totally lost. Based on these data, we concluded that two hydroxyl groups of glabridin are important for the inhibition of melanin synthesis and that the hydroxyl group at the 4’ position of this compound is more closely related to melanin synthesis.
Dermatoscopy and High Frequency Sonography: Two Useful Non‐Invasive Methods to Increase Preoperative Diagnostic Accuracy in Pigmented Skin Lesions
Authors: KRÄHN GERTRAUD , GOTTLÖBER PETRA , SANDER CHRISTIAN , PETER RALF U. 
Published: July 2006

Dermatoscopy and high frequency sonography have recently been combined to increase diagnostic preoperative accuracy in the treatment of pigmented skin lesions. In this monocentric study 80 patients with pigmented skin lesions were evaluated clinically, by dermatoscopy, and 20 MHz‐sonography followed by dermatohistopathological evaluation; 39 malignant melanomas, 37 common nevi, 3 dysplastic nevi, and 1 nevus Spitz were diagnosed histologically. In 72 of the 80 cases (91.3%) dermatoscopical diagnoses were confirmed by histopathology, compared to only 79% correct clinical diagnoses. For the mere clinical diagnosis of melanoma sensitivity was 79%, specificity was 78% and diagnostic accuracy was 65%. All diagnostic values increased by dermatoscopy: sensitivity reached 90%, specificity was 93%, and diagnostic accuracy was 83%.In order to determine tumor thickness preoperatively tumor thickness was measured by 20 MHz sonography. The correlation of tumor thickness between histometric and sonographic results was determined for nevi (r = 0.93) and melanoma (r = 0.95); 74.3% of melanomas were diagnosed correctly within an 0.2 mm range. Regarding the clinical important limit of 1 mm tumor thickness, 87.2% were diagnosed in accordance with histometric evaluation.An increase of 18% in diagnostic accuracy by dermatoscopy and 87.2% of correctly diagnosed cases of tumor thickness of malignant melanoma by high frequency sonography clearly demonstrate that these methods should be considered standard procedures in the diagnosis of pigmented skin lesions and will facilitate the decision on necessary surgical treatment.
A Comparative Study of the Effect of Pigment on Drug Toxicity in Human Choroidal Melanocytes and Retinal Pigment Epithelial Cells
Authors: EVES PAULA , SMITH‐THOMAS LINDA , HEDLEY SUSAN , WAGNER MARK , BALAFA CHARIKLIA , NEIL SHEILA MAC 
Published: July 2006

The aim of this study was to investigate whether the presence of pigment affects the sensitivity of pigmented cells of the eye, retinal pigment epithelium (RPE) and choroidal melanocytes (CMs) to the cyto‐toxic effects of xenobiotic drugs.Two approaches were used to compare pigmented versus unpigmented cells: RPE cells were repigmented by phagocytosis of synthetic melanin; UVB irradiation was used to induce an increase in pigment in both RPE and CMs. Three drugs known to induce toxicity in the eye, tamoxifen, chloroquine and thioridazine, were used to assess the sensitivity of cells to xenobiotic drugs.RPE cells were more resistant than CMs to the cytotoxic effects of all three drugs by a factor of 5‐fold for tamoxifen, 7‐fold for thioridazine and 30‐fold for chloroquine. When RPE cells were repigmented using synthetic melanin, their sensitivity to tamoxifen was unchanged, they showed a slightly improved response to thioridazine (after 3 days of incubation with this drug), but they showed greatly increased toxicity to chloroquine (after 1 and 3 days of exposure to the drug), suggesting accumulation of this latter drug on the synthetic melanin.UVB irradiation was used to achieve an increase in the pigment content of both RPE and CMs. CMs were much more sensitive to UVB than RPE cells. CMs appeared to synthesise pigment via DOPA oxidase activity; RPE cells showed an increase in fluorescent material independent of any detectable DOPA oxidase activity. Irrespective of the nature of the pigment that UVB induced in melanocytes and RPE cells, their subsequent response to thioridazine and chloroquine was unchanged by the presence of this pigment.
Civil Discovery: Lawyers’ Views of Its Effectiveness, Its Principal Problems and Abuses
Authors: Brazil Wayne D. 
Published: July 2006

This article, the second in a three-part series based on interviews of 180 civil litigators in Chicago, describes lawyers’ assessments of the health of the discovery system and their views about the relative severity of several major problems and abuses that burden the discovery process. The data present a disturbing picture of the way the discovery system functions, especially in larger cases. Big case litigators are much unhappier with the current state of affairs in discovery than are their smaller case counterparts, and apparently for good reason. Tactical jockeying, evasive and dilatory practices, and various forms of harassment play major and costly roles in a high percentage of large lawsuits. And in at least one of every two big cases the discovery system fails to distribute the relevant information to all the parties. Perhaps the most dramatic evidence of disaffection with the current state of affairs in major litigation, however, is the widespread support the lawyers expressed for more aggressive judicial involvement in the process and for more frequent, telling use of sanctions to punish its abusers.The third article in this series will report the lawyers’ reform proposals and will explore some of the implications of the data described here.
Giving and Getting Respect: Prestige and Stratification in a Legal Elite
Authors: Slovak Jeffrey S. 
Published: July 2006

This article focuses on the corporate actor elite of Chicago's legal community—those attorneys who practice law with and for the major business, social, civic, and cultural organizations in the city. A continuation of a previous article, this article focuses on the differential allocation of professional respect made within that elite. Specifically, the discussion centers on the “second-class citizenship” in the legal community to which elite house counsel are relegated by elite partners in private law firms.
The first half of the article probes the social bases for that stigma. Examining a number of alternative explanations, it offers most support to one based on differences in the educational preparations of the respondents, to the effect that house counsel attended less prestigious law schools and performed less outstandingly at these schools than did firm partners at theirs. In the concluding half of the article, the effects of the stigma on elite social cohesion and commonality of purpose are examined. What emerges from this analysis is the finding that the house counsel stigma—strongly felt as it may be by all concerned—nevertheless generates no lasting lines of social cleavage within the corporate actor legal elite.
Processing Workers' Compensation Claims in Illinois
Authors: Sincere Lois R. 
Published: July 2006

The substitution of no-fault compensation for recoveries at tort law in cases of work-related injuries would, according to turn-of-the-century reformers, minimize resort to adjudication. Charges of unanticipated controversy and excessive litigation under state compensation statutes, however, have been raised periodically for several decades.This article presents the findings of current research into the prevalence of disputes, attorney involvement, and court suits under workers' compensation legislation in Illinois, the locale of specific criticism. The author offers an explanation of the obstacles to discovering the incidence of work-related injuries, along with a description of the handling of both undisputed and disputed claims. By following the itinerary of a sample of 6, 652 compensation claims filed during 1978 through several stages of administrative and judicial processing, she then examines the persistence of these primarily disputed claims from initiation to resolution. Her major finding is that under workers' compensation legislation in Illinois, litigation, whether defined as attorney involvement or court action, may not be as excessive as charged. The research uncovers the need for more precise standards for defining a surfeit of controversy and offers suggestions for meeting this need.
Police Accountability and the Media
Authors: Skolnick Jerome H. , McCoy Candace 
Published: July 2006

This article explores First Amendment theory and the role of the media in generating police accountability through public understanding of police organizations. We argue that free speech theory can and should look beyond “abridgment” issues and raise questions about the civic responsibility of the press to inform the public about key governmental institutions. The media's concern with crime news, we found, vastly overshadows its coverage of the police us a complex, in-teresting, and expensive governmental agency. Reporting about police institutional patterns and policies contributes more toward fulfilling First Amendment values-not only that of “checking” police excesses, but of facilitating the goal of enlightened citizen participation in local government.Those who won our independence believed…that public discussion is a political duty; and that this should be a fundamental principle of American government. They recognized the risks to which all human institutions are subject.
Constructing the New Political Criminology: Power, Authority, and the Post-Liberal State
Authors: Scheingold Stuart A. 
Published: July 2006

The purpose of this paper is to make a case for a new political criminology—that is, to argue that a meaningful and coherent intellectual enterprise is developing across disciplinary lines. This new political criminology is distinctive in three ways:
• It is criminology in that it is rooted in conceptions of, and concerns about, the ramifications of street crime.
• It is political in that its focus is on the way crime control strategies both reflect and influence the distribution of power within the polity.
• It is new in that it is influenced by postmodern understandings of, and disillusionment with, the liberal state.