h-BN-layer-induced chiral decomposition in the electronic properties of multilayer graphene.

We discuss the chiral decomposition of non-symmetric stacking structures. It is shown that the low-energy electronic structure of a Bernal stacked graphene multilayer deposited on h-BN consists of chiral pseudospin doublets. N-layer graphene stacks on the h-BN layer have N/2 effective bilayer graphene systems and one effective h-BN layer if N is even or [Formula: see text] effective graphene bilayers plus one graphene monolayer modified by an h-BN layer if N is odd. We present the decomposition procedure and derive the recurrence relations for the effective parameters characterizing the chiral subsystems. In this case, the effective parameters consist of interlayer couplings and on-site potentials in contrast to pure graphene multilayer systems where only interlayer couplings are modified. We apply this procedure to discuss the Klein tunnelling phenomena and quantitatively compare the results with pure graphene multilayer systems.

[Neuroendocrine neoplasms of the breast]. / Neuroendokrine Neoplasien der Mamma.

Neuroendocrine neoplasms (NEN) of the breast are specific tumor entities. According to the literature up to 5% of breast neoplasms are malignant epithelial neoplasms of the breast. They are defined by a neuroendocrine (NE) architecture and cytology combined with an expression of the neuroendocrine vesicle markers chromogranin A and/or synaptophysin. The diagnosis is supplemented by the receptor status and the proliferative activity. According to the World Health Organization (WHO) classification of 2012 the following groups of NEN are distinguished: (1) invasive breast carcinoma with NE differentiation, (2) well-differentiated neuroendocrine tumor (NET) and (3) poorly differentiated small cell carcinoma (NEC). This review article focuses on (1) the definition and basic principles of diagnostics, (2) the history, nomenclature and WHO classification from 2003 and 2012, (3) the frequency of breast NEN, (4) the hereditary background and functional activity, (5) the expression of receptors and (6) the possible clinical implications. In addition, the first results of a retrospective single center study (n = 465 patients with breast cancer over a time period of 4 years) on the frequency of NEN of the breast at the Breast Center of the University Hospital Düsseldorf are presented. In this study a frequency of 4.5% of NEN was found based on a diagnostic cut-off of > 50% Chromogranin A and/or synaptophysin positive tumor cells.

Midfacial fractures in children.

The purpose of the study was to present a modern classification and discuss the treatment of midfacial fractures in children. From the beginning of 1 January 1998 to 31 October 2000, 147 children were treated for different craniofacial fractures. Among them 28 patients (19 %) had extensive midfacial fractures complicated by impaired vision and/or CNS dysfunction and were treated surgically. The fractures were divided into: zygomatico-orbital (1 pt) and zygomatico-orbito-maxillary (5 pts), isolated orbital wall fractures (14 pts) and naso-orbital dislocations (2 pts), upper facial portion dislocations (2 pts) and fronto-naso-orbital (2 pts) or cranio-orbital fractures (2 pts). Clinical examination revealed mainly dysfunction of facial morphology and aesthetics (enophthalmos, telecanthus), CSF leakage, impairment of vision and restricted eyeball movements. Ophthalmological, neurological and radiological (Waters view, CT, NMR) examinations were performed in all cases. The treatment consisted of bone repositioning, reconstruction with autologous bone grafts and three-dimensional stabilisation using titanium plates. Twenty-three pts were operated on before and 5 pts after 7th day after trauma. The restoration of normal facial morphology was achieved in 26 patients. In 2 cases it was impossible because of the destruction of soft tissue and an extremely extensive bony trauma. Better reposition of bony fragments, prompt healing and better final results were achieved in patients operated before day 7 after trauma. Achieving good results in midfacial fractures requires prompt and adequate treatment and a multidisciplinary (paediatric, maxillofacial, plastic surgeons, neurosurgeon, ophthalmologist) team.

Perspectives of clinical application of bone morphogenetic proteins in children.

UNLABELLED: The purpose of the study was to modify the method of Bone Morphogenetic Protein (BMP) extraction from bovine bones, estimate the osteoinductive potential of the extracted protein fractions in relation to the degree of protein purity and to test collagen formed in porous discs as a carrier. It was required before BMP application in reconstructive surgery in children. MATERIAL AND METHOD: BMP preparation from bovine bones was conducted according to a modification of Luyten's method. Three fractions of different degree of purity - demineralised bone matrix "M", extract "E", and fraction after hydroxyapatite column "HP" - were tested for their osteoinductive potential. They were implanted on a collagen carrier into the right rat femoral muscle pouch. Controls were implanted in the same way in the left muscle pouch. The discs were removed after 3 and 6 weeks and tested for alkaline phosphatase activity, a marker of new bone formation. RESULTS: Out of the 10 animals used for testing the osteoinductive potential of matrix fraction, 7 results were positive and 3 negative. In the case of the extract fraction, the analysis was conducted for 3 weeks on 9 rats and 6 weeks on 13 rats. Six and 11 positive results were obtained, respectively. In the HP group 5 animals were observed for 3 weeks (3 positive, 2 negative) and 10 animals for 6 weeks (7 positive, 3 negative). In the case of the extract, the differences in alkaline phosphatase activity after 6 weeks were statistically significant (p

[A case of neurilemmoma of the tongue]. / Przypadek nerwiaka oslonkowego podstawy jezyka.

The rare case of neurilemmoma of radix tongue was presented. The tumor was removed surgically by mouth approach. The main histopathological and clinical features of neurilemmoma were shown. The review of literature was presented.