Arylphorin was purified from larvae of the blowfly Calliphora vicina and studied in its oligomeric form and after dissociation at pH 9.6 into native subunits. In accordance with earlier literature, ...it was electrophoretically shown to be a 500 kDa hexamer (1 X 6) consisting of 78 kDa polypeptides ( = subunits). Electron micrographs of negatively stained hexamers show a characteristic curvilinear, equilateral triangle of 12 nm in diameter (top view) and a rectangle measuring 10 X 12 nm (side view). Alternatively, particles in the top view orientation exhibit a roughly circular shape 12 nm in diameter. Crossed immunoelectrophoresis revealed the presence of a major subunit type; the nature of a very minor and a third immunologically separated component remains unclear. A novel 2 X 6 arylphorin particle was detected and isolated. It comprises less than 10% of the total arylphorin material and shows a long, narrow interhexamer bridge in the electron microscope. An arylphorin dissociation intermediate identified as a trimer (1/2 X 6) was isolated; its possible quaternary structure is discussed on the basis of electron micrographs. The epitope of monoclonal antibody Ec-7 directed against tarantula (Eurypelma californicum) hemocyanin subunit d and also reactive to Calliphora arylphorin was traced to a highly conserved peptide of 27 amino acids localized in the center of the protein. The primary structure of Calliphora arylphorin as published in our preceding paper (Naumann and Scheller 1991) is compared in detail to the sequences of spider and spiny lobster hemocyanin. This revealed a basic framework of 103 strictly conserved amino acids. Isofunctional exchanges are proposed for another 76 positions. On the basis of these similarities, and the published three-dimensional model of spiny lobster hemocyanin, a detailed model of the quaternary structure of Calliphora arylphorin is presented. A second larval storage protein previously termed protein II was purified from Calliphora hemolymph. It was demonstrated to be a 500 kDa hexamer of 83 kDa subunits. In the electron microscope it shows a cubic view 9 nm in length with a large central hole and a rectangular view (9 X 10 nm) with a large central cavity. A morphologically very similar hemolymph protein was detected in Drosophila melanogaster larvae. From its structural appearance it is uncertain whether protein II belongs to the hemocyanin superfamily or not.
Posterior choanal atresia (PCA) is an uncommon congenital anomaly which consists of an anatomical malformation and a bony and/or membraneous diaphragm that separates the nasal cavity from the ...nasopharynx. Therefore nasal breathing as well as mucus discharge are impeded. If present bilaterally it has life threatening consequences. The goal of treatment in neonates and infants is to safely open and maintain the patency of the nasal choana without damaging surrounding normal anatomical structures or affecting future growth patterns of the palate and the posterior nasal cavity – paranasal sinuses complex. In every case an unimpeded nasal breathing and mucus drainage towards the deeper aero-digestive tract must be achieved.
The therapeutical strategy is strictly surgical. Traditional surgical approaches are the transnasal, the transseptal, the transpalatine and – but seldom – the transvestibular-transmaxillary route. All these surgical approaches have one in common: There is either a quite large and tissue compromising access with rather good exposition of PCA and a high risk for intra- and postoperative complications, or a bad access and visibility of the PCA due to a very limited tissue sparing route. Neither intraoperative microscopy nor endoscopy could completely help out of this dilemma. We present with this paper
the new transoral retropalatine approach for endoscopic laser surgery of PCA
. We report on our first five patients with an age of 0 to 9 years all treated from 1998 to 2001 by this approach with fiber guided diode laser surgery (wavelength: 940 nm) and an endoscopic laser application sheath which derives from our concept of Functional Endoscopic Endonasal Laser Surgery (FEELS). Stenting of the re-opened choana with an individually customized U-shaped nasopharyngeally open silicone tube, which was transseptally fixed and hidden in the nasal cavity, was performed for 6 weeks. The outcome and follow up showed excellent results concerning wound healing; no complications, no re-stenosis and no evidence for growth changes in the surrounding choanal and palatal anatomy were encoutered.
Epistaxis is a widespread, though usually bland, symptom of highly varying etiopathogenesis. ENT specialists face the challenge of selecting the best individual treatment modality when it recurs in ...connection with prominent vascular convolutions and angiectases in Kiesselbach's area (Little's spot), pyogenic granulomas of the nasal mucosa, intranasal hemangiomas or disseminated manifestations of Osler-Weber-Rendu's disease in the nasal cavity. Precise dosing and excellent visualization of the entire operating area render videoendoscopy-guided laser surgery an effective approach for sealing these hemorrhage-prone areas. In our clinically controlled prospective study, we examined the suitability of the fiber-guided diode laser for managing the most frequent causes of recurrent epistaxis, as mentioned above. Despite a still limited patient population, a close follow-up ranging up to 24 months has demonstrated the high therapeutic efficiency of this novel laser system (940 nm diode laser), which is already applied with great success for turbinate hyperplasia treatment, septal crest and spur vaporization and concha bullosa resection in functional endoscopic endonasal laser surgery (FEELS) (12a). Diode laser surgery of epistaxis-generating mucosa was usually performed using a bare-fiber-guided noncontact technique with the use of special glass-spatulas for compression and coagulation of vessels in outpatients under local anesthesia; using the chopped mode, moderate, individually adjusted powers were applied over short laser exposure times and relatively long exposure pauses.The diode laser did not differ in its therapeutic efficiency from the Argon or Nd:YAG laser, the two systems we preferred to use for this treatment during the last decade. But rega
rds to its lower optical penetration and coagulation depth in combination with the use of different glass-spatulas, the diode laser appeared to involve a somewhat lower potential risk of wound-healing impairment.
This is particularily significant compared to the “free hand-held treatment” without the compression and coagulation method and compared to the use of the Nd:YAG laser, especially at the nasal septum.
