Insight into the mechanism of the decrease in mechanical strength and water-holding capacity of gels made from oxidized gelatin.

The purpose of this study was to investigate the effect of oxidation on the physicochemical properties of gelatin and gelatin gels. Porcine skin gelatin was oxidized with different concentrations of H2O2 (0-30 mM). Upon oxidation of gelatin, a significant modification of amino acid residues including glycine, proline, hydroxyproline, and hydroxylysine occurred. Zeta-potential, ordered secondary structure and the fraction of triple-helix decreased, while particle size and surface hydrophobicity increased. Gels made from oxidized gelatin showed a looser network structure indicated by scanning electron microscope, and the gels had a weakened mechanical strength and water-holding as compared to non-oxidized gelatin gels. Based on these results, a mechanism of how oxidation affects the gelatin gel properties was proposed: Oxidation-induced increase of hydrophobicity and decrease of net charges promoted aggregation between gelatin molecules, thereby limiting the formation of triple-helix, which subsequently leads to a loose network structure and eventually a weakened gel strength and water-holding capacity.

Histopathologic changes after tracheal reconstruction with a scraped partial mucosa jejunal autograft / 临床耳鼻咽喉头颈外科杂志

OBJECTIVE@#To explore the histopathological changes of the new trachea reconstruction with a scraped partial mucosa jejunal autograft hy microscope and transmission electron microscope.@*METHOD@#Eight canine models of extensive circumferential tracheal defects with revascularized jejuna combined with NiTi alloy mesh tube were established. Operations were performed on these dogs under general anesthesia by intravenous ketamine. A 6.5 cm length of segment of the jejunum was resected. The graft was prepared by scraping the partial mucosa with operating knife blade and dry gauze. During the resecting course, micro-vascular anastomoses were done between the mesenteric artery and the right common carotid artery,and the mesenteric vein with the right common carotid vein. The silicone intraluminal stent was placed in the lumen of the jejunal segment and was removed the fourth week after operation. A Ni-Ti alloy prothesis was placed over the jejunal segment, with the mesenteric vascular supply egressing through the longitudinal defect of the mesh tube. Then the free jejunum was used to reconstruct the tracheal defects. Biopsy were performed and recorded at the 1 at, 2nd, 3rd and 4th postoperative months. All specimens were observed by microscope and transmission electron microscope examinations.@*RESULT@#Eight dogs postoperative all survived expected time. One month after operation, the tracheointestinal snastomosis showed smooth and was covered by continuous internal lining. The mucosa of the jejunum was slightly atrophied. Two months after operation, examination of the jejunal mucosa of the autografts demonstrated obviously thinned. The lumen of the reconstructed trachea was covered by squamous epithelium entirely at 3 months postoperatively. The partial squamous epithelium has transformed ciliated columnar epithelium at 4 months postoperatively.@*CONCLUSION@#A free scraped partial jejunum reconstructed trachea can accelerated the atrophying process of mucous epithelization and promoted mucosal metaplasia of the jejunum. The reconstructed tracheal lumen has completely transformed squamous epithelium at 3 months postoperatively and partial squamous epithelium has transformed ciliated columnar epithelium at 4 months postoperatively.

Study on the height and weight in children with obstructive sleep apnea hypopnea syndrome / 临床耳鼻咽喉头颈外科杂志

OBJECTIVE@#To investigate the influence of obstructive sleep apnea hypopnea syndrome (OSAHS) on children's growth.@*METHOD@#Fifty-three children diagnosed as OSAHS were included in the treatment group and underwent tonsillectomy or adenoidectomy, and 51 normal children were employed as the control group. Main data monitored by PSG and growth hormone (GH) in children of the treatment group were recorded before and after surgery, in addition, growth hormone, height and weight of children in the treatment group and control group were respectively recorded and compared.@*RESULT@#Height and weight of children with OSAHS before treatment were lower than that of the normal children and the difference was significant (P<0.05). Compared with the data before surgery, oxygen saturation of blood in children of treatment group recorded by PSG increased (P<0.05), while value of other data decreased (P<0.05). Growth hormone in children of the treatment group was lower than that of the control group and the difference between two group was significant (P<0.05), while the content of growth hormone in children of the treatment group elevated after 3 months postoperatively and at this time no difference was found between the two groups.@*CONCLUSION@#Children with OSAHS present the symptom of upper airway obstruction, which badly affects sleep quality and results in decreased secretion of growth hormone and finally the height and weight of children is got involved. Timely surgery is necessary to alleviate the symptom.

Clinical analysis of 111 patients with non-invasive fungal rhino-sinusitis / 临床耳鼻咽喉头颈外科杂志

OBJECTIVE@#To analyze the clinical characteristics, diagnosis and treatment course and clinical effect of non-invasive fungal rhino-sinusitis, and to investigate the diagnostic and treating methods and factors affecting the clinical outcome.@*METHOD@#A retrospective study was conducted on 111 patients who were diagnosed with noninvasive fungal rhino-sinusitis from 2005 to 2009 in our department. Clinical symptoms, endoscopic and CT examinations, surgical methods, surgical outcomes and the treatment of the recurrent cases were reviewed.@*RESULT@#Eighty-six cases were reassured of the non-invasive fungal rhino-sinusitis by means of clinical symptoms, endoscopic and CT examinations. All the patients who underwent functional endoscopic sinus surgery showed satisfying clinical effect and no complications occurred. During the follow-up, recurrence was found in 12 cases 1 to 5 years postoperatively, and 7 were cured after medication and debridement under endoscope in outpatient department while the clinical outcome of the other 5 was unsatisfactory.@*CONCLUSION@#Non-invasive fungal rhino-sinusitis is distinctive in endoscopic and CT examination which is different from common chronic rhino-sinusitis, and endoscopic sinus surgery is an effective treatment for the disease. Radical debridement and successful drainage of the nasal sinus is the key factor affecting the effect of the treatment and clinical outcome.

Primary study of diagnosis and treatment of huge petrous apex cholesteatoma( clinical analysis of 2 cases) / 临床耳鼻咽喉头颈外科杂志

Objective:To investigate the clinical features, operative approach and method of petrous apex chol-esteatoma, to improve the effect of operation and to reduce surgical complications. Method:Two cases of patients with giant petrous apex cholesteatoma were treated by trans labyrinth approach,one of which was successfully operated with oto-endoscope-assisted surgery. Result; No cerebrospinal fluid leakage, infection, vertigo or disequilibrium was found in the two cases after operation. Conclusion:Temporal CT and MRI are of great importance in clinical diagnosis and choice of surgical approach. Surgery by trans-labyrinth approach paves way for removing cholesteatoma thoroughly, dealing with facial nerve and repairing cerebrospinal fluid leakage. Surgery is considered to be the only way to cure petrous apex cholesteatoma, while the key procedure to prevent recurrence lies in complete removal of lesion, long-time strict follow up and regular clearance of the surgical field.

Primary study of diagnosis and treatment of huge petrous apex cholesteatoma (clinical analysis of 2 cases) / 临床耳鼻咽喉头颈外科杂志

OBJECTIVE@#To investigate the clinical features, operative approach and method of petrous apex cholesteatoma, to improve the effect of operation and to reduce surgical complications.@*METHOD@#Two cases of patients with giant petrous apex cholesteatoma were treated by trans labyrinth approach, one of which was successfully operated with oto-endoscope-assisted surgery.@*RESULT@#No cerebrospinal fluid leakage, infection, vertigo or disequilibrium was found in the two cases after operation.@*CONCLUSION@#Temporal CT and MRI are of great importance in clinical diagnosis and choice of surgical approach. Surgery by trans-labyrinth approach paves way for removing cholesteatoma thoroughly, dealing with facial nerve and repairing cerebrospinal fluid leakage. Surgery is considered to be the only way to cure petrous apex cholesteatoma, while the key procedure to prevent recurrence lies in complete removal of lesion, long-time strict follow up and regular clearance of the surgical field.