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The importance of isoprenylation and Nf1 deficiency in K-RAS-induced cancer /Sjögren, Anna-Karin, January 2009 (has links)
Diss. (sammanfattning) Göteborg : Göteborgs universitet, 2009. / Härtill 3 uppsatser.
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Inteligência em portadores de Neurofibromatose 1.Bolini, Helenice Bianchi 27 October 2010 (has links)
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Previous issue date: 2010-10-27 / The practical problem observed referred to the clinical symptoms of NF1, involving intellectual performance and psychosocial characteristics of their carriers. This sends us to the NF1-intelligence interface. Objective: To identify and compare indices of intelligence and their frequencies in patients with NF1, attended at CEPAN. Methods and Casuistry: Medical records were used in research, semi-structured interview, the Wechsler Scales and Test Progressive Matrices Scale-General. Were applied indidually, to the 77 subjects, of which 30 patients with NF1, 17 family members, and 30 non- carriers between 2006 and 2010. The data were treated qualitative-quantitative. Results: The socioeconomic and cultural rights did not differ between subjects. Minors (<20 ) and larger (>20 ) time spent in the execution of Test Progressive Matrices Sacale-General were relatives of patients with NF1 and most were using medication. Mean correct responses were lower in patients with NF1, they had one and two symptoms that bothered when they were diagnosed, currently, the troubled portability three, four and two symptoms. Patients with NF1 had their first symptoms identified with more than five years age, they had relatives suffering from NF1 1st and/or 2nd degrees of relatedness (vertical transmission). They had mild MR and moderate, and learning disabilities. The subjects of this investigation showed TIQ; VIQ; TIQ/Gc; IOP/Gv; IVP/Gt average and below average; although the ability Reasoning/ Fluid Intelligence Gf category V. Conclusions: The subjects of this investigation have average and average lower, with limited sustainability. There are differences in intellectual performance among them: relatives of patients with NF1 are superior to the carriers and no- carriers are superior to both. There are mental retardation, learning disabilities, difficulties visual-perceptual-motor, memory impairments, and speech in written and spoken language in patients with NF1. There are no correlations between TIQ/Gc; IMO/Gsm; ICV/Gc; IOP/Gv; IVP/Gt and number of symptoms. There is no correlation between IQ, intellectual level, types, numbers, uncomfortable symptoms and age of onset of symptoms. / O problema prático observado, referiu-se aos sintomas clínicos de NF1, que envolviam o desempenho intelectual e as características psicossociais de seu portador, remetendo-nos à interface inteligência Neurofibromatose 1-NF1. Objetivo: Identificar e comparar os índices de inteligência e suas frequências em portadores de NF 1 atendidos no CEPAN. Casuística e Métodos: Utilizou-se pesquisa em prontuários; entrevista semi-estruturada; as Escalas de Wechsler e Testes de Matrizes Progressivas - Escala Geral, aplicados individualmente a 77 sujeitos, dos quais 30 portadores de NF1, 17 seus familiares e 30 não-portadores, entre 2006 e 2010. Os dados receberam tratamento quali-quantitativo. Resultados: As características socioeconômicas e culturais não diferiram entre os sujeitos Os tempos menores (<20 ) e maiores (>20 ) gastos na execução do Raven - Escala Geral foram de familiares e portadores de NF1, que mais faziam uso de medicação. As médias de acertos de portadores de NF1 foram as menores; possuíam 1 e 2 sintomas que os incomodavam quando foram diagnosticados; atualmente, era a portabilidade de 3, 4 e 2 sintomas que os incomodavam; primeiros sintomas identificados com mais de 5 anos; possuíam parentes portadores de NF1 de 1º e/ou 2º graus de parentesco (transmissão vertical); apresentaram RM leve e moderada; e distúrbio de aprendizagem (QI>70) em portadores de NF1. Os sujeitos dessa investigação apresentaram quocientes de inteligência e índices fatoriais médios e médio-inferiores; a capacidade Raciocínio/ Inteligência Fluida Gf encontrou-se comprometida-categoria V. Conclusões: Os sujeitos da investigação possuem inteligência média e média inferior, porém com dificuldade de sustentabilidade. Há diferenças de desempenho intelectual: familiares de portadores de NF1 são superiores aos portadores de NF1; e não portadores são superiores a ambos. Há retardo mental, distúrbio de aprendizagem, disfunção no desenvolvimento da linguagem dificuldades viso-motoras e perceptuais, deficiências de memória e de expressão na linguagem escrita e verbal em portadores de NF1; ausência de correlação entre QIT/Gc; IMO/Gsm; ICV/Gc; IOP/ Gv; IVP/ Gt e número de sintomas; e ausência de relação entre QI; nível intelectual; tipos; números; incômodos de sintomas e faixa etária do aparecimento dos primeiros sintomas.
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Neurofibromatose tipo 1: reparaÃÃo imediata com retalhos cutÃneos loco-regionais / Neurofibromatose type 1: immediate repairing with cutaneous remnants loco-regionaisErcilio Guimaraes do Nascimento 10 December 2004 (has links)
Instituto Dr. Josà Frota / A meta da presente pesquisa foi apresentar tÃcnicas cirÃrgicas associadas ou isoladas, na tentativa de, utilizando cirurgias menos traumÃticas e mais eficientes, proporcionar resultados menos estigmatizantes e deformantes para dar aos portadores da neurofibromatose tipo 1 (NF1) uma qualidade de vida mais digna e melhor integraÃÃo social. Estudou-se neste trabalho 30 pacientes portadores de NF1 por um perÃodo de seis anos, durante os quais se comparou a eficiÃncia de diversas tÃcnicas cirÃrgicas em lesÃes localizadas em vÃrias regiÃes anatÃmicas do corpo e cujas ressecÃÃes atingiram dimensÃes que variaram entre 3 e 51cm. A utilizaÃÃo do tratamento cirÃrgico mostrou ser a maneira mais simples, eficaz e rÃpida para a soluÃÃo de afecÃÃo tÃo traumÃtica para os pacientes. Mesmo quando da utilizaÃÃo de retalhos cutÃneos com comprometimento residual da pele o seguimento operatÃrio mostrou que a doenÃa nÃo evoluiu e nÃo houve qualquer sinal de malignizaÃÃo. Das opÃÃes mais empregadas foram os retalhos cutÃneos loco-regionais, as que melhores resultados proporcionaram, quer do ponto de vista funcional como estÃtico, e os que causaram menor nÃmero de seqÃelas. Vinte e um pacientes se beneficiaram de excisÃes e reparaÃÃes com retalhos e os demais com procedimentos mais simples, o que lhes permitiu uma melhor qualidade de vida e melhor aceitaÃÃo social. Os retalhos cutÃneos loco-regionais foram aqueles que possibilitaram o reparo das maiores Ãreas cruentas e a ressecÃÃo dos mais volumosos tumores, com uma mÃdia de 16,4 x 8,1 cm e um peso mÃdio de 373 g. O âSâ itÃlico com uma mÃdia de 8,5 x 5,5 cm e 135 g e a âZâ plÃstia com 8,5 x 4,8 cm e 82,8 g mostraram-se eficazes para a reparaÃÃo de lesÃes de mÃdio porte onde aparecem como uma das opÃÃes para reparaÃÃo imediata das ressecÃÃes da NF1.ExcisÃo e Sutura com 4,9 x 2,8 cm e 33,8 g e pequenos enxertos de pele estÃo indicados nas lesÃes de dimensÃes menores e de localizaÃÃes especiais, como a face e nariz. NÃo foram detectadas malignizaÃÃes nas 52 peÃas encaminhadas ao laboratÃrio de histopatologia.
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NF1 tumor suppressor in epidermal differentiation and growth - implications for wound epithelialization and psoriasisKoivunen, J. (Jussi) 03 August 2003 (has links)
Abstract
Neurofibromatosis type 1 (NF1) is a dominantly inherited neurocutaneous disorder caused by mutations in the NF1 gene. Common clinical manifestations associated with NF1 are neurofibromas, café-au-lait macules (CALM), axillary freckling and Lisch nodules of the iris. Other important manifestations are vasculopathy, a variety of osseous lesions, including short stature, scoliosis and pseudoarthrosis, optic gliomas and an increased risk for certain malignancies. The best characterized function of the NF1 gene is to act as a downregulator of Ras proto-oncogene signalling by accelerating the switch of active Ras-GTP into inactive Ras-GDP. The NF1 gene is considered a tumor suppressor since some malignancies may display a loss of heterozygosity or homozygotic inactivation of the gene.
The present study investigated the behaviour and function of the NF1 gene during keratinocyte differentiation, wound healing and psoriasis using human epidermis and epidermal keratinocytes as a model. The NF1 protein was shown to associate with the intermediate filament network during keratinocyte differentiation both in vitro and in vivo, and it is thus suggested to play a role in the cytoskeletal re-organization or in the formation of cell adhesions. NF1 gene expression was also studied in psoriasis, in which keratinocytes are hyperproliferative and cell differentiation is altered. NF1 gene expression was downregulated in psoriatic keratinocytes both in vivo and in vitro, suggesting that the NF1 gene might have role in downregulating keratinocyte proliferation. During epidermal wound healing, NF1 gene expression was increased. However, the process of wound healing showed no apparent differences between NF1 patients and controls. Furthermore, an increased number of cells immunoreactive for active Ras-MAPK was demonstrated in vascular tissues of NF1 patients, but not in epidermal keratinocytes or dermal fibroblasts. The finding suggests that the NF1 protein functions as a Ras-GAP in some, but not all tissues.
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Substantial Pain Burden in Frequency, Intensity, Interference and Chronicity among Children and Adults with Neurofibromatosis Type 1Kongkriangkai, Alanna M., B.S. 29 September 2017 (has links)
No description available.
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Human bone marrow stem cells—a novel aspect to bone remodelling and mesenchymal diseasesLeskelä, H.-V. (Hannu-Ville) 28 November 2006 (has links)
Abstract
The stem cell is a primitive cell that is capable of dividing to reproduce itself and can give rise to a selection of differentiated progeny. Stem cells are thought to be involved in or even main factors in many diseases. In postnatal humans, mesenchymal tissues have the capacity to regenerate from stem cells called mesenchymal stem cells (MSC). It is currently thought that these cells will become the basis of therapy for many diseases. In the present study, a novel in vitro method was developed to examine human bone marrow derived MSC differentiation into osteoblast lineage, and to study the role of MSC in a variety of mesenchymal diseases.
The ability of MSCs to differentiate into osteoblasts was investigated during aging. In addition, the interindividual variability in the osteogenesis of MSCs and in the osteoblastic response of MSC to estrogen and testosterone was studied. Furthermore, an ex vivo model using a human aortic valve microenvironment was developed to explore whether the extracellular matrix influences the osteoblastic differentiation of the MSC. Finally, the role of MSC in neurofibromatosis type 1 (NF1) related congenital pseudarthrosis of the tibia (CPT) was studied.
It was found that after menopause the osteogenic potential of MSCs does not decrease. It was also found that estrogen receptor (ER) alpha genotype confers interindividual variability of response to estrogen and testosterone in MSC derived osteoblasts. In addition, it was found that the non-calcified valves with living valve cells inhibited osteogenesis of co-cultured MSCs, whereas the calcified and devitalised valves promoted differentiation towards an osteoblastic lineage. Finally, MSCs from NF1-related pseudarthrosis showed altered NF1 gene expression, poor osteoblastic differentiation and bone formation.
In conclusion, MSC can be easily isolated from the bone marrow and MSC has the capacity to regenerate tissue even at later stages of life. These results could help explain the contradictory effects of 17β-estradiol (E2) on osteoblasts in vitro and might also provide new insights into understanding the differences in responses to hormone replacement therapy. It seems that adult stem cells from bone marrow undergo milieu-dependent differentiation to express phenotypes that are similar to cells in the local microenvironment. Finally, the NF1 gene was shown to have a role in bone development and remodelling.
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NF1 tumor suppressor in skin:expression in response to tissue trauma and in cellular differentiationYlä-Outinen, H. (Heli) 19 April 2002 (has links)
Abstract
Type 1 neurofibromatosis (NF1) syndrome is caused by a mutation of the NF1 gene. NF1 protein (neurofibromin) contains a domain which is related to the GTPase activating protein (GAP) and accelerates the switch of active Ras-GTP to inactive Ras-GDP. The clinical symptoms of NF1 patients include e.g. the formation of benign neurofibroma tumors and hyperpigmented lesions of the skin. The NF1 protein has been referred to as a tumor suppressor since cells of malignant schwannomas of NF1 patients may display loss of heterozygosity of the NF1 gene.
In the present study, the expression of the NF1 gene was investigated during tissue repair in human skin. Elevated NF1 protein levels were seen in a fibroblastic cell population of healing wounds. In vitro studies were designed to investigate NF1 expression in dermal fibroblasts under the influence of growth factors that are operative during wound healing. Platelet-derived growth factor (PDGF) isoforms AB and BB and transforming growth factor β1 (TGFβ1) elevated NF1 mRNA levels in cultured dermal fibroblasts. In further studies, histological examination on apparently healthy skin of NF1 patients revealed frequently small masses of neurofibromatous tissue at the vicinity of hair follicles. Thus, action of the NF1 gene appears to be an integral part of normal tissue repair. Enhanced NF1 tumor suppressor expression may serve to limit excessive fibrosis in wound healing.
As Ras proteins play a role in the regulation of cell differentiation and formation of cell junctions, the functional expression of NF1 protein was elucidated using differentiating keratinocytes as an in vitro model system. The results demonstrate that an intense NF1 tumor suppressor signal on intermediate filaments was temporally limited to the period in which the formation of desmosomes takes place. In analogy to NF1 protein, a rapid elevation of NF1 mRNA level was detected following initiation of differentiation. Interestingly, NF1 mRNA hybridization signal polarized towards cell-cell contact zones. This finding recognizes a potential way for post-transcriptional modification of NF1 expression and targeting of translation to subplasmalemmal location. The results demonstrate that the function of NF1 protein is associated with the formation of cell junctions, and thus to cellular communication.
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PKC and neurofibromin in the molecular pathology of urinary bladder carcinoma:the effect of PKC inhibitors on carcinoma cell junctions, movement and deathAaltonen, V. (Vesa) 16 October 2007 (has links)
Abstract
This study examined the role of tumor suppressor neurofibromin and Protein kinase C (PKC) in urinary bladder cancer, and the effect of PKC inhibitors on cancer cell behaviour.
Tumor suppressor protein neurofibromin is a product of the NF1 gene, a mutation of which causes the most common hereditary tumor syndrome, type 1 neurofibromatosis. NF1 gene mutations and changes in expression have been demonstrated in malignancies, unrelated to type 1 neurofibromatosis. The best known function of neurofibromin is its Ras GTPase accelerating function. Thus, it functions as a Ras inactivator. This study demonstrated for the first time that the NF1 gene is expressed in normal and malignant urinary bladder epithelium and in cultured bladder carcinoma cells in mRNA and at the protein level. Furthermore, neurofibromin expression is decreased during bladder carcinogenesis. It can be speculated that this may lead to increased Ras activity in urinary bladder cancer.
The PKC family is composed of several different isoenzymes which are responsible for a number of important intracellular events and cellular functions. Many of these are also important in cancer development and progression. The results demonstrate changes in expression of PKC α and βI isoenzymes in urinary bladder carcinoma. Furthermore, the results relate the increased expression of isoenzymes to increased PKC enzyme activity and the high proliferation rate of the cancer cells. In addition, this study utilizes small molecular inhibitors of PKC isoenzymes in order to study the effect of the inhibition of these isoenzymes on cancer cell behaviour in vitro and in vivo. The study mainly focuses on the function of PKC α and βI isoenzymes and on the effects of inhibition of these by using Go6976. The results show that Go6976 inhibits cancer cell growth, migration and invasion in vitro, and tumor growth in a mouse model. The use of Go6976 induces changes in desmosomes and adherens junctions, and in focal adhesions and hemidesmosomes. The results also show that Go6976 functions as a cell cycle checkpoint abrogator and increases the cytotoxicity of two classical chemotherapeutic agents, doxorubicin and paclitaxel. In the future, it may be possible that Go6976 or related drugs could be used in clinical cancer treatments.
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Evolution et facteurs pronostiques de la Neurofibromatose 1 / Factors Associated to Neurofibromatosis1Sbidian, Émilie 23 October 2012 (has links)
La Neurofibromatose 1 (NF1) est une maladie autosomique dominante dont l’évolutivité est inconnue. En effet, ni le type de mutation du gène, la gravité d’éventuels cas familiaux, ni une première complication ne permettent de prédire le pronostic de la maladie. L’objectif général de ce travail de thèse était de cibler les malades les plus à risque de morbi-mortalité au cours de la NF1. Méthode. Les différents travaux se sont appuyés sur les données phénotypiques de patients NF1 suivis dans le Réseau NF-France labellisé par le ministère de la Santé. Il s’agit d’une filière nationale monothématique ayant pour mission la prise en charge des malades atteints de NF1. Une cohorte d’environ 2500 malades est actuellement suivie dans ce réseau. Résultats. La mortalité des patients NF1 a tout d’abord été comparée à celle de la population générale française par l’estimation du rapport de mortalité standardisée (SMR). Entre 1980 et 2006, 1 895 patients NF1 ont été rétrospectivement inclus dans la cohorte. Un excès de mortalité était observé chez les [10-20[ ans (SMR=5.2, IC95% : 2.6 – 9.3, p<10-4) et les [20-40[ ans (SMR=4.1, IC95% : 2.8 – 5.8, p<10-4). Les principales causes de décès étaient la transformation de neurofibromes internes en tumeurs malignes des gaines nerveuses (TMGN). Une étude cas témoins portant sur 208 patients NF1 a permis d’expliquer le risque de mortalité accru chez les patients présentant des neurofibromes sous cutanés (SC-NF) en confirmant en IRM la présence chez ces patients de neurofibromes internes à fort risque de transformation en TMGN (OR=4.3, IC95% : 2.2 – 8.2). Cet effet était d’autant plus marqué que le nombre de SC-NF était important et notamment au-delà d’un seuil de 10 (OR=82, IC95% : 10.4 – 647.9) et que les neurofibromes internes étaient diffus (OR=14.7, IC95% : 3.8 – 57.3) et de taille ≥ 3 cm (OR=6.3, IC95% : 2.3 – 17.4). Les patients présentant des SC-NF représentent 20 à 30% de la population NF1. Afin d’identifier les patients à risque de développer une TMGN, nous avons élaboré un score prédictif de la présence des neurofibromes internes à partir des caractéristiques phénotypiques des patients. La présence de SC-NF (OR=4.7, IC95% : 2.1 – 10.5), l’absence de neurofibromes cutanés (OR=2.6, IC95% : 0.9 – 7.5), un âge inférieur ou égal à 30 ans (OR=3.1, IC95% : 1.4 – 6.8) et moins de 6 tâches café au lait (OR=2, IC95% : 0.9 – 4.6) étaient les variables qui constituaient le NF1Score. Le NF1Score = 10*(âge ≤ 30 ans) + 10*(absence de neurofibromes cutanés) + 5*(moins de 6 tâches café-au-lait) + 15*(plus de 2 neurofibrome sous cutanés) avait une excellente adéquation (test C de Hosmer-Lemeshow=4,53 avec 7ddl, p>0,50) et une capacité discriminante satisfaisante (aire sous la courbe ROC non paramétrique = 0,75 [0,68-0,82]). Enfin, l’expression phénotypique variant au cours du temps chez un même patient nous avons réalisé une étude spécifique chez l’enfant. Ainsi, l’âge (OR=1.1, IC95% : 1.0 – 1.2), la présence de xanthogranulomes (OR=4.5, IC95% : 0.9 – 21.7), celle de neurofibromes sous cutanés et plexiformes (OR=5.0, IC95% : 1.8 – 13.6) étaient indépendamment associés à celle des neurofibromes internes chez l’enfant NF1 de moins de 17 ans. Dans cette dernière étude, les neurofibromes internes se développaient de façon exponentielle pendant l’adolescence et plus précocement chez les femmes en accord avec les données de la littérature. Conclusion. La période à risque de développer des neurofibromes internes semblent donc sesituer entre l’adolescence et l’âge de 30 ans. Les recommandations de suivi pourraient prendre en compte le phénotype à risque, mais également la période de survenue de ces complications en réévaluant l’intérêt dans ce contexte d’investigations complémentaires / Neurofibromatosis-1 (NF1) is a common autosomal dominant condition which is a source of various multisystemic manifestations related either to the accumulation of neurofibromas or to specific developmental abnormalities. There are no obvious factors that predict disease progression. Thus, the aim of our project was to characterize the phenotype of NF1 patients with a severe prognosis. Patients were identified among adults with NF-1 followed up in the Réseau NF-France. The Réseau NF-France is a French medical network devoted to neurofibromatosis 1. It has elaborated recommendations for the management of the disease and recommended a coordinated follow-up in specialized multidisciplinary centres. About 2 500 patients were enrolled. We first evaluated the mortality in a large retrospective cohort of NF1 patients. The standardized mortality ratio (SMR) with its 95% confidence interval (CI) was calculated as the ratio of observed over expected numbers of deaths. Between 1980 and 2006, 1895 NF1 patients were seen. The excess mortality occurred among patients aged 10 to 20 years (SMR=5.2; CI, 2.6-9.3; P<10-4) and 20 to 40 years (SMR, 4.1; 2.8-5.8; P<10-4). The main cause of death was the malignant tumors of the nerve sheath (MPNSTs) developing from preexisting internal neurofibromas. Then, a case-control study including 208 patients with NF1 allowed us to explain the increased risk of mortality among NF1 patients harboring subcutaneous neurofibromas (SC-NF) by the presence of internal neurofibromas (NF) at risk of MPNSTs systematically investigated with imaging (MRI) (OR=4.3, IC95% : 2.2 – 8.2). The association with SC-NF was stronger for patients with ten or more SC-NFs (OR=82, IC95% : 10.4 – 647.9) and for diffuse (OR=14.7, IC95% : 3.8 – 57.3), and ≥ 3 cm (OR=6.3, IC95% : 2.3 – 17.4) internal neurofibromas. Patients with SC-NF constituted 20 to 30% of the NF1 population. So, to characterize patients at risk of developping MPNSTs, we developped and validated a clinical score for predicting internal neurofibromas in adults. Four variables were independently associated with internal neurofibromas: at least two subcutaneous neurofibromas (OR=4.7, IC95% : 2.1 – 10.5), age ≤30 years (OR=3.1, IC95% : 1.4 – 6.8), absence of cutaneous neurofibromas (OR=2.6, IC95% : 0.9 – 7.5), and fewer than six café-au-lait spots (OR=2, IC95% : 0.9 – 4.6). The NF1Score was computed as 10 . [age ≤30 years] + 10 • [absence of cutaneous neurofibromas] + 15 • [≥2 subcutaneous neurofibromas] + 5 • [<6 café-au-lait spots]). Calibration was excellent (Hosmer-Lemeshow statistic=4.53; degrees of freedom=7; P>0.5) and discrimination was good (AUC-ROC= 0.75; 95%CI, 0.7-0.8). Finally clinical expressivity is variable and manifestations of NF1 change at different times in an individual’s life. Consequently, a specific study was needed in pediatric patients. We identified easily recognizable clinical characteristics associated with internal neurofibromas in children with NF1. By multivariate analysis, age (OR=1.1, IC95% : 1.0 – 1.2), xanthogranulomas (OR=4.5, IC95% : 0.9 – 21.7), and presence of both subcutaneous and plexiform neurofibromas (OR=5.0, IC95% : 1.8 – 13.6) were independently associated with internal neurofibromas. Moreover internal neurofibromas increased during adolescence. Excess risk of developing internal neurofibromas seems to occur between the adolescence and the age of to 30 in NF1 patients. These clinical features in adults and children would define a new population at risk for complications that may need closer clinical and imaging follow-up
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Calcium signaling in epithelium:special focus on Hailey-Hailey and Darier diseases, neurofibromatosis 1 and transitional cell carcinomaLeinonen, P. (Pekka) 30 December 2008 (has links)
Abstract
This study utilized normal and defective epithelial cell cultures and epidermal skin samples to examine intra- and intercellular calcium signaling. The main interests of this thesis were Hailey-Hailey disease (HHD), Darier disease (DD), neurofibromatosis 1 (NF1) and transitional cell carcinoma (TCC).
HHD and DD diseases are rare autosomal dominant skin disorders characterized by dissociation of epidermal keratinocytes (acantholysis) at the suprabasal layer of the epidermis. HHD and DD diseases are caused by mutations in the genes encoding the calcium pumps in the Golgi apparatus (hSPCA1) and endoplasmic reticulum (SERCA2b), respectively. Due to these mutations calcium uptake into the Golgi apparatus or ER is diminished, which is believed to cause abnormal cell junction protein processing and dissociation of keratinocytes. This study utilized electron probe microanalysis (EPMA) and demonstrated for the first time that lesional areas of HHD and DD and non-lesional areas of DD epidermis display abnormally low calcium content in the basal cell layer. Furthermore, ATP mediated calcium signaling was impaired in cultured HHD and DD keratinocytes and epidermal ATP receptor localization was disrupted. In conclusion, these results suggest that the low calcium content in the basal cell layer is the reason for suprabasal ruptures in HHD but not necessarily in DD lesions, and that abnormal ATP receptor localization contributes to the calcium signaling defects.
NF1 deficient keratinocytes display abnormally low resting cytosolic calcium levels and it has been suggested that the calcium concentration in the lumen of the endoplasmic reticulum is decreased. This study demonstrated that NF1 keratinocytes rely mostly on ATP mediated calcium signaling while normal keratinocytes rely mostly on gap junctional intercellular communication (GJIC).
Studies with TCC cells have demonstrated that gap junctions participate in intercellular calcium wave propagation. This thesis demonstrated that the ATP mediated pathway was also operational in calcium wave propagation in normal uroepithelial and TCC cell cultures. Furthermore, impaired calcium wave propagation in the TCC cell culture could be improved through PKC α/βI –isoenzyme inhibition with Gö6976. Gö6976 treatment increased connexin 26 clustering at plasma membrane but did not alter expression level of the protein.
This thesis contains a wide repertoire of calcium detection techniques including a new cutting-edge technology for elemental calcium detection of epidermal samples. These techniques can be used for molecular specific analysis of calcium signaling in epithelial cells.
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