Arsenic contamination of coarse-grained and nanostructured nitinol surfaces induced by chemical treatment in hydrofluoric acid.

XPS measurements of coarse-grained and nanostructured nitinol (Ni(50.2)Ti(49.8)) before and after chemical treatment in hydrofluoric acid (40% HF, 1 min) are presented. The nanostructured state, providing the excellent mechanical properties of nitinol, is achieved by severe plastic deformation. The near-surface layers of nitinol were studied by XPS depth profiling. According to the obtained results, a chemical treatment in hydrofluoric acid reduces the thickness of the protective TiO(2) oxide layer and induces a nickel release from the nitinol surface and an arsenic contamination, and can therefore not be recommended as conditioning to increase the roughness of NiTi-implants. A detailed evaluation of the resulting toxicological risks is given.

Surface studies of coarse-grained and nanostructured titanium implants.

The results of XPS measurements of nanostructured Ti (ns-Ti) prepared with a help of severe plastic deformation (SPD) have been presented. We have measured XPS spectra of core levels (Ti 2p, O 1s, C 1s, F 1s) and valence bands before and after treatment of ns-Ti-implants in HF. The obtained data have been compared with XPS measurements of untreated and acid treated coarse-grained Ti (cg-Ti). According to these measurements the surface composition has not practically been changed by reduction of grains size of Ti-implants. It has been found that the surface of both types of implants is covered with thick TiO2 layer. The acid treatment reduces the surface contamination of ns-Ti and cg-Ti by hydrocarbons and induces better passivation and formation of more thick TiO2 layer. It has been shown that severe plastic deformation not only improves mechanical properties but also preserves corrosion stability of Ti-implants.

Pitanguy's method of protruding ear correction from our own experience: review of 80 cases.

A recent review of the literature revealed more than 20 methods of correction of protruding ears. Pitanguy's cartilage island flap technique is still not widespread. However, it is extraordinarily versatile and effective from our own experience. The aim of this study is to present our own experience in the correction of prominent ears using this method. According to Pitanguy's cartilage island flap technique, 80 patients were operated on at the Private Plastic Surgery Clinic from 1992 to 1999. There were 45 (56%) female and 35 (44%) male patients, aged from 9 to 37 years (22 years on average). All procedures were performed under local anesthesia. In the follow-up period of 1 to 8 years the final aesthetic results were estimated as very good in 68 (85%) patients and good in 12 (15%) patients. Early complications in the form of bleeding occurred in three (3.75%) patients. Asymmetry in the ears' position was qualified as a late complication and occurred in four (5%) patients.

General anesthesia via tracheosubmental intubation from our own experience.

In our department from 1995 to 1998, 30 patients were operated on under general anesthesia via tracheosubmental intubation (TSI). No local or general complications were observed. Operating in the field free from the intubation tube is very comfortable for a surgeon, while for an anesthesiologist the safety of the tube and efficiency of ventilation are very important. TSI, as a technically simple, safe, and efficient procedure, is extremely helpful in the surgical treatment of patients with simultaneous multifragmentaric and comminuted fractures of the maxilla and mandible, and in orthognathic and aesthetic plastic surgery of the face, where assessment of facial symmetry and occlusion is especially important.

Marcus Gunn Jaw-Winking Phenomenon: management and results of treatment in 19 patients.

From 1980-1995, 19 patients displaying the Marcus Gunn Phenomenon (MGP) were treated in the Department of Maxillofacial Surgery of the Jagiellonian University in Kraków, Poland. Sixteen patients were operated on according to the Neuhaus method, in one case bilaterally. In three patients, the upper eyelid, after partial transsection of the levator muscle, was suspended from the frontal muscle on autogenous temporal fascia strips. At postoperative follow-up, the width and symmetry of the palpebral fissures were evaluated as well as persistent symptoms of synkinetic eyelid movement. In 13 (68.4%) patients, proper width and symmetry of the palpebral fissures were obtained, whereas in the remaining six (36.1%) marked improvement and decreased asymmetry of palpebral fissures were achieved. Pathological synkinesis disappeared totally in 16 (84.2%) of the patients on operated.

Comparison of the DNA content in recurrent and nonrecurrent basaliomas of the face.

The ploidy status of 5 recurrent and 7 nonrecurrent basaliomas was investigated using a CAS 200 image analyser. All recurrent basaliomas were aneuploid in contrast to nonrecurrent ones representing the euploid status. The percentage of cells in S phase in recurrent basaliomas was twice as high as in nonrecurrent ones. The authors conclude that aneuploidy in primary tumour can be a warning signal for recurrences and these patients should undergo special control.

Actinomycotic osteomyelitis of the mandible: review of 15 cases.

The authors have analysed 15 cases of actinomycotic osteomyelitis of the mandible. Primary actinomycotic inflammation of the mandible was diagnosed in nine patients, secondary in six patients (following fracture or resection of the mandible). The diagnosis was established on the basis of the clinical examination confirmed by bacteriological and/or histopathological tests. The basic method of treatment was antibiotic therapy of long duration. Surgical treatment was performed in all patients. Twelve of fifteen patients who had received the therapy and proved asymptomatic for 1 year to 23 years were recognized to be cured of the disease. In three patients, a single recurrence of the disease was observed after 1.5-2 months.

Regulation and function of the tissue-specific transcription factor HNF1 alpha (LFB1) during Xenopus development.

We review the data available on the structure, developmental appearance and embryonic regulation of the tissue-specific transcription factor HNF1 alpha (LFB1) in Xenopus. The expression of the HNF1 alpha gene starts early in embryogenesis shortly after mid-blastula transition and the protein accumulates in the region of the embryo where liver, pronephros and gut--tissues that contain HNF1 alpha in the adult--are developing. The cofactor DCoH, known to stabilize dimer formation of HNF1 alpha, is present as a maternal factor in the egg and has a partially distinct tissue distribution compared to HNF1 alpha. This implies that DCoH does not only modulate HNF1 alpha dimerization but may also cooperate with other transcription factors. By injecting HNF1 alpha promoter CAT constructs into fertilized Xenopus eggs we obtained activation of the injected gene restricted to the region of the developing larvae expressing endogenous HNF1 alpha. Deletion analysis allowed to define the OZ-element that is essential for embryonic activation. This element also occurs in other promoters activated at mid-blastula transition in the embryo and interacts with the maternal factor OZ-1. As the HNF1 alpha promoter also contains functional binding sites for HNF4 and HNF1, we postulate that all of these transcription factors contribute to the cascade leading to proper embryonic activation of the HNF1 alpha gene.

Significance of P-53 antigen in malignant melanomas and naevi of the head and neck area.

DO-7 antibody against p-53 antigen was applied for investigation of melanomas of facial skin (25 cases), oral cavity (17 cases), eye (18 cases) and naevi (25 cases). The p-53 index value (% of p-53 positive cells) was correlated with the thickness of the tumour, the presence of metastases and survival time. The difference in p-53 index between naevi and melanomas was statistically significant (p < < 0.01). A significant correlation was found between the p-53 index value and the thickness of the tumour, the presence of metastases and follow-up for patients with skin, oral and ocular melanomas. The possible diagnostic and prognostic significance of p-53 antigen in melanomas and naevi of the head and neck area is discussed.

CD-44: a marker of metastases of head and neck melanomas.

Specimens of 38 melanomas of the oral cavity and facial skin and 23 lymph nodes with melanoma metastases were stained immunohistochemically for the presence of variants 5, 6, 7 and 8 of CD-44 antigen. A positive reaction was observed only for variant 7-8 in primary melanomas as well as in lymph nodes with metastases from melanoma. The CD-44 score (percentage of CD-44 positive cells chi intensity of reaction) correlated with metastatic behaviour of tumours and was greater in metastatic lymph nodes than in primary tumours.

Immunohistochemical demonstration of S100 protein in malignant melanomas of the facial skin and oral cavity.

Immunohistochemical demonstration of S100 protein was performed in 56 cases of malignant melanoma of the facial skin and oral cavity. The depth of invasion was measured comparatively in HE sections and in sections stained for S100 protein. Comparison of measured melanoma invasion depth in S100- and HE-stained sections revealed a deeper invasion of the tumor in S100-stained slides than in slides stained routinely with HE according to Breslow's melanoma staging procedure. A reverse relationship between the intensity of immunohistochemical staining for S100 protein and survival rate was found in both melanomas of the facial skin and oral cavity. Although the presence of S100 protein has been demonstrated previously in skin melanomas, no similar investigations concerning the oral mucosa have been performed up to now.

[Diagnosis and results of treatment of blow-out fracture of the orbital floor]. / Rozpoznawanie i wyniki leczenia rozprezajacego zlamania dna oczodolu.

In the last 20 years, 273 patients with blow-out fracture of the orbital floor were treated. Surgery was performed in 242 of them (88.6%). The typical features of this type of fracture as well as the methods and results of treatment are presented. Criteria of the recovery were disappearance of diplopia and decrease of enophthalmos.

Squamous cell carcinoma arising in an odontogenic cyst. Report of three cases.

Primary intraosseous carcinoma of the jaws is an uncommon lesion. The majority of these develop in preexisting odontogenic cysts. Three cases of primary intraosseous squamous cell carcinomas of the mandible and maxilla, with evidence of origin in the odontogenic cysts are described. The recent literature on carcinomas arising in jaws cysts is reviewed.

An application of MIB antibody to the retrospective study of melanomas of oral mucosa and facial skin.

A new monoclonal antibody prepared against a fragment of Ki-67 antigen MIB, from Dianova, was applied for investigation of malignant melanomas of facial skin (25 cases) and the oral cavity (25 cases), which were routinely embedded in paraffin. The values of the Ki-67 index (expressed as a percentage of positive nuclei) were correlated with TNM characteristics of tumors and patient survival. Significant correlation was found between the Ki-67 index and the level of lymph node involvement (N value), the presence of distant metastases and the time of patient survival. A positive relationship between the Ki-67 value and tumor size was also observed although it lacked statistical significance.

Genomic structure of the Xenopus laevis liver transcription factor LFB1.

Liver factor B1 [LFB1, also called hepatocyte nuclear factor 1 (HNF1)] is a tissue-specific vertebrate transcription factor that is present in the liver, intestine, stomach and kidney. The LFB1 protein contains an unusual homeobox that is characterized by an insertion of 21 amino acids (aa) not found in any other homeodomain protein. We have isolated and characterized the genomic sequences encoding the LFB1 of Xenopus laevis. By comparing the genomic sequences with the cDNA clones, we could identify nine exons. In general, the position of the introns is identical to the one previously found in the rat. However, the C-terminal activation domain of LFB1 contains, in each species, an exon that is split in two in the other species. The homeobox of the X. laevis LFB1 contains an intron at exactly the position where the 21 aa typical for LFB1 are inserted. This is in agreement with the structure found in the rat gene and supports the notion that the LFB1 homeobox evolved separately from the other genes encoding homeodomain proteins.

Elements and factors involved in tissue-specific and embryonic expression of the liver transcription factor LFB1 in Xenopus laevis.

LFB1 (HNF1) is a tissue-specific transcription factor found in the livers, stomachs, intestines, and kidneys of vertebrates. By analyzing the promoter of the Xenopus LFB1 gene, we identified potential autoregulation by LFB1 and regulation by HNF4, a transcription factor with a tissue distribution similar to that of LFB1. Injection of LFB1 promoter-chloramphenicol acetyltransferase constructs into Xenopus eggs revealed embryonic activation that is restricted to the region of the developing larvae expressing endogeneous LFB1. Proper embryonic activation was also observed with a rat LFB1 promoter. Deletion analysis of the Xenopus and rat promoters revealed that in both promoters embryonic activation is absolutely dependnet on the presence of an element that contains CCNCTCTC as the core consensus sequence. Since this element is recognized by the maternal factor OZ-1 previously described by N. Ovsenek, A. M. Zorn, and P. A. Krieg (Development 115:649-655, 1992), we might have identified the main constituents of a hierarchy that leads via LFB1 to the activation of tissue-specific genes during embryogenesis.

Chimeric liver transcription factors LFB1 (HNF1) containing the acidic activation domain of VP16 act as positive dominant interfering mutants.

The transcription factor LFB1 (HNF1) involved in the expression of liver-specific genes is characterized by a serine/threonine-rich activation domain whose transactivation potential differs between mammals and Xenopus. Exchanging the activation domain between the Xenopus and rat LFB1, we produced chimeric transactivators whose activities are primarily determined by the origin of the activation domain. By replacing the serine/threonine-rich activation domain of LFB1 with the acidic activation domain of VP16, we generated transcription factors that act as dominant positive interfering mutants on endogenous LFB1 in differentiated hepatoma cells. As these LFB1/VP16 chimeras show no self-squelching as observed with wild-type LFB1 and increase the activity of saturating LFB1, we postulate that acidic and serine/threonine-rich activation domains use different targets of the basal transcription machinery. Stable transfection of various LFB1 derivatives, including those containing the VP16 transactivation domain, into the dedifferentiated C2 hepatoma cell resulted in cell clones stably expressing LFB1 function. However, as in none of these clones the chromosomal albumin genes are activated, we conclude that the presence of functional LFB1 may not be sufficient to reactivate liver-specific functions lost in dedifferentiated hepatoma cells.