Biodegradable polymer membrane used as septal splint.

The treatment of a crooked nose is one of the most challenging rhinoplastic procedures. Correction of the abnormally curved or fractured septum has been reported using mostly scoring techniques, septoplasty and submucous resection techniques; cartilaginous spreader grafts can also be sutured to the distorted septum. Extracorporal septal straightening and repositioning/refixation is another useful but difficult technique. A common problem of septal cartilaginous grafting techniques is to harvest enough straight cartilage to correct the deformity. (Other donor sites such as rib cartilage are used, but harvesting additional cartilage is a time-consuming procedure and carries the risk of donor site morbidity.) Recent studies have been published using alloplastic internal splinting of the deformed septum. The use of poly p-dioxanone foils and porous polyethylene has been suggested before. In this study, a novel grafting material, a PolyMax membrane that has potential advantages over both materials, is presented. This is a porous biodegradable polymer made out of 70:30 poly(L-lactide-co-D,L-lactide) that remains stable for at least 7 months. Poly p-dioxanone loses its stability after only 2 months, whereas porous polyethylene is a permeable material that is controversial due to possible complications in cases of membrane exposure and infection. In this preliminary report the PolyMax membrane was used successfully in 3 patients.

Salvage therapy with oral etoposide in recurrent and/or metastatic squamous cell carcinoma of the head and neck.

BACKGROUND: The purpose of this retrospective evaluation was to assess the palliative effect of oral etoposide in heavily pretreated patients with squamous cell carcinoma of the head and neck. PATIENTS AND METHODS: Between October 1995 and February 2003, a total of 26 patients with metastatic and/or recurrent squamous cell carcinoma of the head and neck (SCCHN) were treated with oral etoposide. Therapy consisted of etoposide at a total dose of 100 mg daily for 7 days and was repeated every 4 weeks until progression of disease or for a maximum of 8 courses. Eighteen patients underwent primary surgery of the tumour followed by adjuvant irradiation or surgery after neoadjuvant radiochemotherapy. Eight patients had primary irradiation with or without concomitant chemotherapy. All patients previously received at least one palliative chemotherapy with cisplatin/5-floururacil (5-FU) or cisplatin/taxotere. Patients did not routinely receive anti-emetic medication. RESULTS: All patients were eligible for toxicity and survival assessment, and 24 of 26 patients for response evaluation according to an intention-to-treat principle. Two patients had a partial response (8 percent); disease was stable in 9 patients (35 percent) and progressed in 13 patients (50 percent). The median time to progression for all patients was 3 months (range, 2-54), and median overall survival was 10 months (range, 2-52). Toxicity was in general mild and moderate (Grade 1 and 2), except three patients, who experienced Grade 3 anaemia, and one patient who had Grade 3 thrombocytopenia without bleeding complications. Severe nonhematologic adverse reactions were not seen, except for alopecia. CONCLUSION: Our data suggest that oral etoposid is markedly effective, in regard to stabilization of disease and survival, and an excellent tolerated therapy for pretreated patients with recurrent and/or metastatic head and neck carcinomas. Its advantage over other commonly used and more intensive regimens such as 5-fluorouracil (5-FU) + cisplatin or taxane-containing combinations is its superior tolerance, in particular the incidence of nausea and vomiting, complete alopecia, and/or hematologic complications.

Dysgnathia, orthognathic surgery and spinal posture.

The aim of this study was to evaluate the spine by video rasterstereography before and after orthognathic surgery. Twenty-nine patients (17 patients with a skeletal class III, 7 patients with a skeletal class II, and 5 patients with mandibular asymmetry) were evaluated preoperatively and 1 year postoperatively. Video rasterstereography is a method of back surface measurement and shape analysis using the moire topography. Orthognathic surgery in cases of class III and asymmetry did not lead to significant changes in body posture. In class II patients it led to some changes in body posture, but without orthopaedic consequences. It is concluded that orthognathic surgery causes minimal or no change in body posture.

Invitro study of adherent mandibular osteoblast-like cells on carrier materials.

Augmentation of the craniofacial region is necessary for many aesthetic and reconstructive procedures. Tissue engineering offers a new option to supplement existing treatment regimens. In this procedure, materials composed of hydroxyapatite (HA), of synthetic or natural origin, are used as scaffolds. The aim of this study was to evaluate the effects of three HA materials on cultured human osteoblasts in vitro. Explant cultures of cells from human alveolar bone were established. Human osteoblasts were cultured on the surface of HA calcified from red algae (C GRAFT/Algipore), deproteinized bovine HA (Bio-Oss) and bovine HA carrying the cell binding peptide P-15 (Pep Gen P-15). Cultured cells were evaluated with respect to cell attachment, proliferation and differentiation. Cells were cultured for 6 and 21 days under osteogenic differentiation conditions, and tissue-culture polystyrene dishes were used as control. The ability of cells to proliferate and form extracellular matrix on these scaffolds was assessed by a DNA quantification assay, protein synthesis analysis and by scanning electron microscopical examination. Osteogenic differentiation was screened by the expression of alkaline phosphatase. The osteoblastic phenotype of the cells was monitored using mRNA levels of the bone-related proteins including osteocalcin, osteopontin and collagen Type I. We found that cells cultured on C GRAFT/Algipore) and Pep Gen P-15 showed a continuous increase in DNA content and protein synthesis. Cells cultured on Bio-Oss showed a decrease in DNA content from Day 6 (P < 0.05) to Day 21 (P < 0.0001) and protein synthesis on Day 21 (P < 0.005). Alkaline phosphatase activity increased in cells grown on C GRAFT/Algipore and Pep Gen P-15 in contrast to cells grown on Bio-Oss, in which the lowest levels of activity could be observed on Day 21 (P < 0.05). Reverse transcriptase polymerase chain reaction analysis confirmed the osteoblastic phenotype of the cells grown on all three materials throughout the whole culture period. The results of our in vitro study show that the differences in metabolic activity of cells grown on HA materials are directly related to the substrate on which they are grown. They confirm the excellent properties of HA carrying the cell binding peptide P-15 and HA calcified from red algae as used in maxillofacial surgery procedures.

Aggressive fibromatosis of the mandible: a case report.

An extensive tumour in a 7-year-old girl, leading to severe disfigurement, proved to be an aggressive fibromatosis on histological examination. Eighteen months after surgery there was no evidence of recurrent disease. This suggests that tumour resection and reconstruction of the mandible had been successful. Contrary to some reports, tumour resection led to curative therapy whereas radiotherapy failed.

[Evidence of osteocalcin expression in osteoblast cells of mandibular origin growing on biomaterials with RT-PCR and SDS-PAGE/Western blotting]. / Nachweis der Osteokalzinexpression osteoblastärer Zellen mandibulären Ursprungs, wachsend auf Biomaterialien, mittels RT-PCR und SDS-PAGE/Western Blotting.

A new approach to addressing difficult tissue reconstructive or replacement problems in the oral cavity is to engineer new tissue by using selective cell transplantation on polymer scaffolds. The current study characterized the osteoblastic nature of adherent mandibular cells on biomaterials, which could have a potential use as scaffolds for tissue engineering strategies. Cells of mandibular origin from one patient were cultivated on three different biomaterials (PepGen P-15 trade mark, Frios Algipore, and OsteoGraf/LD-700) for 7 and 14 days and osteocalcin expression was demonstrated by RT-PCR and SDS-PAGE/Western blotting. In order to explicitly characterize only the adherent cells on the biomaterials, we first separated the biomaterials with adherent cells from the culture plate before trypsinization. We could demonstrate that cell growth of adherent mandibular osteoblast-like cells was significantly higher on biomaterials with an organic component (PepGen P-15 trade mark ) in comparison to Frios Algipore and OsteoGraf/LD-700, respectively. In conclusion, only the explicit study of adherent cells at the gene and protein levels gives information about the osteoconductivity of biomaterials.

Determination of the protooncogene ets-2 gene transcript in human brain at the atto-gram-level by the use of competitive RT/PCR.

Protooncogenes (PO) play a crucial role for brain biology and pathology. Only the concerted action of protooncogenes enables normal brain development. The reliable and sensitive quantification of brain PO is still holding centre stage in neurobiological research. The aim of our study was therefore the determination of PO in minute amounts of brain areas. For this purpose we decided to apply the most sensitive detection principle of competitive reverse transcriptase polymerase chain reaction using capillary electrophoresis and laser-induced fluorescence detection. We selected the PO ets-2 for our studies as this transcription factor was shown to be involved in neurodegenerative disease. As little as 10 ng of total RNA each were extracted from 5 different regions of human postmortem brain and used in the assay system. Our results revealed that the ets-2 gene transcript was detectable at the atto-gram level in the brain (54.5 +/- 17.7 ag/ 10 ng RNA in the occipital lobe, 34.2 +/- 7.5 in temporal lobe, 40.2 +/- 15.6 in the frontal lobe, 31.4 +/- 15.7 in the cerebellum, and undetectably low in the parietal lobe). This is the first report at this sensitivity level providing neurobiology with a powerful analytical tool.

Evidence against the current hypothesis of "gene dosage effects" of trisomy 21: ets-2, encoded on chromosome 21" is not overexpressed in hearts of patients with Down Syndrome.

BACKGROUND: The major current concept for the pathogenesis of the Down Syndrome (DS) phenotype including congenital heart disease (CHD) is the so-called "gene dosage effect." According to this hypothesis, genes encoded by chromosome 21 at the "critical region" (which is thought to be crucial for the development of the DS phenotype) are overexpressed in the trisomic state, thus leading to an imbalance of genes as, e.g., the protooncogene ets-2, superoxide dismutase, etc. METHODS: We studied heart biopsies obtained at surgery from 6 patients with DS and 7 patients with congenital heart disease. ets-2-mRNA steady state levels were determined by a competitive reverse transcription-polymerase chain reaction (RT-PCR) technique which allowed the determination of this gene at the attomol level. RESULTS: ets-2 mRNA in total ventricular tissue of DS patients showed concentrations of 0.60 +/- 0.42 fg/10 ng total RNA (mean, +/- SD). When normalized versus the housekeeping gene beta-actin to rule out general transcriptional changes in that disorder, the ratio of 0.56 +/- 0.28 (mean, +/- SD) was calculated. ets-2 mRNA in total ventricular tissue of patients with non-DS CHD showed concentrations of 0.45 +/- 0.22 fg/10 ng total RNA (mean, +/-SD) and ratios of 0.48 +/- 0.35 (mean, +/-SD). No differences could be found at the p<0.05 level. CONCLUSION: No absolute quantification of a gene incriminated in the "gene dosage effect-hypothesis" was performed so far and the only approach to (semi-) quantitative determination of the ets-2 gene using northern blotting was published on one individual DS sample only. This is the first report to clearly show that no overexpression of ets-2 can be found in heart of patients with DS, thus providing evidence against the current gene dosage effect-hypothesis.

Expression of the transcription factor ETS2 in brain of patients with Down syndrome--evidence against the overexpression-gene dosage hypothesis.

Overexpression of the transcription factor ETS2 and other genes localized in the socalled critical Down Syndrome region of chromosome 21 due to a gene dosage effect, is an attractive hypothesis for the explanation of the Down Syndrome phenotype. The overexpression of ETS2, however, has never been demonstrated in a human organ. We therefore challenged this hypothesis determining ETS2 levels in several brain regions of patients with Down Syndrome as compared to controls. We used a highly sensitive and quantitative RT-PCR method for the determination of ETS2 mRNA steady state levels in frontal, parietal, temporal, occipital lobe and cerebellum of 9 adult Down Syndrome patients and 9 adult controls. Significantly decreased ETS2 mRNA steady state levels (16.9 +/- 26.7 attogram mRNA ETS2/10 ng total RNA versus 87.7 +/- 92.9 in controls) in frontal lobe of Down Syndrome brain and decreased ETS2 mRNA steady state levels (6.99 +/- 6.4 attogram mRNA ETS2/100 pg beta-actin versus 19.8 +/- 15.7 in controls) in temporal lobe of Down Syndrome brain were found. In the other brain regions no statistically significant difference was detected. Our data provide evidence against the overexpression hypothesis for the development of the Down Syndrome phenotype. Decreased ETS2 transcripts found in temporal and frontal lobe of patients with Down Syndrome, however, may be involved in the pathogenesis of Down Syndrome including specific neurodegenerative processes and deteriorated plasticity of the brain taking place in Down Syndrome brain, as the concerted action of transcription factors may be seriously impaired.

Overexpression of DNAse I in brain of patients with Down syndrome.

Human DNAse I (EC 3.1.21.1) is an enzyme most probably involved in apoptotic processes. Splicing of the DNAse I primary transcript in normal and apoptotic cells into up to 20 splicing forms and the recent description of a different family of caspase-activated DNAses, hampered studies on the role of DNAse I in apoptosis research. Performing gene hunting in fetal brain of patients with DS we found a sequence with 100% homology to DNAse I and this formed the Rationale for studies in adult DS brain. It was therefore the aim of the study to evaluate DNAse I-mRNA steady state levels in DS brain using adult brain without brain pathologies and Alzheimer's Disease (AD) brain as control, in order to rule out that DNAse I--overexpression may not be specific for DS but rather reflecting apoptosis per se, a hallmark of both disorders. Determination of DNAse I-mRNA steady state levels was carried out by a blotting method in frontal, parietal, temporal occipital lobe and cerebellum. We found significantly increased DNAse I transcripts in brain of DS and AD both, when normalized versus the house-keeping gene beta actin or total RNA. We demonstrate the significant increase of DNAse I--transcript in the pathogenesis of DS and AD suggesting a role for this enzyme in the apoptotic process known to occur in both disorders. We are now going to carry out protein and enzyme activity levels in our laboratory to confirm our findings at the transcriptional level.