Interaction of titanium, zirconia and lithium disilicate with peri-implant soft tissue: study protocol for a randomized controlled trial.

Background: Against the background of increasing use of dental implants, and thus an increasing prevalence of implant-associated complications, a deeper understanding of the biomolecular mechanisms in the peri-implant tissue is needed. Peri-implant soft tissue is in direct contact with transmucosal dental implant abutments. The aim of this trial is to distinguish the biomolecular and histological interactions of various dental abutment materials with peri-implant soft tissue.

Mechanism of high-power NIR laser bacteria inactivation.

Lasers are used in dentistry for a variety of indications. One of these is the disinfection of root canals or the sterilization of residual caries. Many studies have demonstrated the capacity to kill bacteria for lasers but the fundamental mechanism of the laser effect remains quite unclear.

Numerical abnormalities of the Cyclin D1 gene locus on chromosome 11q13 in non-melanoma skin cancer.

Deregulation of the cell-cycle G1-restriction point control via abnormalities of Rb-pathway components is a frequent event in the formation of cancer. The aim of this study was to evaluate numerical aberrations of the Cyclin D1 (CCND1, PRAD1, bcl-1) gene locus at chromosome 11q13 in basal cell carcinomas (BCCs) and squamous cell carcinomas (SCCs) of the skin and to compare it with the Cyclin D1 protein expression. Fluorescence in situ hybridization with DNA-probes specific for the Cyclin D1 gene locus and the centromere of chromosome 11 as well as immunostaining for Cyclin D1 protein was applied on 5 microm serial paraffin sections.

Additional Cyclin D(1) gene copies associated with chromosome 11 aberrations in cutaneous malignant melanoma.

Cyclin D1 (CCND1, PRAD1, bcl-1) is associated with progression through G1 and entry into S phase of the cell cycle, as a partner of cyclin-dependent kinases (CDKs). The aim of this study was to evaluate cytogenetic aberrations of the gene locus at chromosome 11q13 in cutaneous malignant melanoma. Fluorescence in situ hybridisation (FISH) was applied on metaphase spreads of short-term primary cell cultures as well as on 5 microm paraffin tissue sections of primary melanomas and melanoma metastases, and on melanoma cell lines (C32, WM 266-4, HT 144, RPMI 7951, SK MEL 28).

Expression of c-myc and bcl-2 in primary and advanced cutaneous melanoma.

Apoptosis is an important co-factor in the pathogenesis of a plethora of malignancies. Enhanced c-myc activation can result either in proliferation or apoptosis. Coexpression with antiapoptotic bcl-2, which abrogates the apoptotic function of c-myc might lead to an enormous growth advantage of cells.

Chromosome 7 aneusomy. A marker for metastatic melanoma? Expression of the epidermal growth factor receptor gene and chromosome 7 aneusomy in nevi, primary malignant melanomas and metastases.

Receptor tyrosine kinases such as the epidermal growth factor receptor (EGFR) play an important role in a variety of malignant neoplasias, making the search for aberrations in the relevant chromosomes an important issue. Differential expression of the EGFR gene was investigated by reverse transcriptase (RT)-PCR on tissue samples of normal skin, nevi, primary melanomas, and melanoma metastases. The EGFR gene is located on chromosome 7p12.

UVB-induced decrease of p16/CDKN2A expression in skin cancer patients.

The lack of p16 expression has been shown in cultured melanoma cells, however contradictory evidence for p16 expression in melanoma tissues exist. Ultraviolet (UV) C and UVB have been shown to affect p16 expression, which impairs cell cycle regulation in vitro and in vivo. In this study, p16/CDKN2A gene expression was determined by reverse transcription polymerase chain reaction in seven skin cancer patients, in one dysplastic nevus patient and in seven healthy individuals, prior to UVB exposure and at various times after application of one minimal erythema dose (MED).

Coexpression patterns of EGFR, HER2, HER3 and HER4 in non-melanoma skin cancer.

The receptor tyrosine kinases (RTKs) epidermal growth factor receptor (EGFR), HER2, HER3 and HER4 are involved in the pathogenesis of multiple human malignant neoplasias. However, their role in the carcinogenesis of basal cell carcinomas (BCC) and squamous cell carcinomas (SCC) remains to be elucidated. In order to further define the role of these RTKs, 56 human skin tissue samples of normal skin, BCC and SCC were studied by conventional and differential and quantitative reverse transcriptase-polymerase chain reaction (rtPCR).

Extra c-myc oncogene copies in high risk cutaneous malignant melanoma and melanoma metastases.

Amplification and overexpression of the c-myc gene have been associated with neoplastic transformation in a plethora of malignant tumours. We applied interphase fluorescence in situ hybridization (FISH) with a locus-specific probe for the c-myc gene (8q24) in combination with a corresponding chromosome 8 alpha-satellite probe to evaluate genetic alterations in 8 primary melanomas and 33 advanced melanomas and compared it to 12 melanocytic nevi, 7 safety margins and 2 cases of normal skin. Additionally, in metaphase spreads of 7 melanoma cell lines a whole chromosome 8 paint probe was used.

Mutational analysis and expression studies of the neurofibromatosis type 2 (NF2) gene in a patient with a ring chromosome 22 and NF2.

The case of a seriously disabled and retarded female patient with neurofibromatosis type 2 (NF2) is reported. She suffered from bilateral vestibular schwannomas, multiple intracranial meningiomas and neurinomas. The constitutional karyotype of the patient was 46, XX, r(22)/45,XX,-22.