Objective To study expression and significance of keratin 17 and 19 in psoriatic lesion.Method The expression of keratin 17 and 19 in 30 psoriatic lesion and 10 normal skin was measured by immunohistochemistry method.Results The expression level of keratin 17 in the psoriatic lesion was higher than that in the normal skin,the expression level of keratin 19 in the psoriatic lesion was lower than that in the normal skin,there were significant differences in the expression of keratin 17 and 19 between them(P ＜0.05).The optical density level of keratin 17 in the psoriatic lesion was obviously raised compared with the normal skin(5.81 ± 1.42 vs.0,P＜ 0.01).The optical density level of keratin 19 in the psoriatic lesion was obviously decreased compared with the normal skin(0.49 ±0.03 vs.2.03± 1.08,P＜0.05).The optical density level of keratin 17 and 19 showed negative correlation in the psoriatic lesion(r =-0.479,P＜ 0.01).Conclusion Keratin 17 and 19 may play a role in the pathogenesis of psoriasis.

OBJECTIVETo analyze the causes of the vascular crisis and necrosis of free flaps used for reconstruction of defects following head and neck cancer resection and the managements of these issues.

METHODSA total of 850 cases with head and neck tumors who underwent free flap reconstruction from October 2010 to April 2014 were studied retrospectively. The risks for vascular crisis and necrosis were analyzed with one-factor analysis and multivariate analysis.

RESULTSThe total success rate of 95.1% (808/850) for the free flap reconstruction was obtained. Twelve flaps due to poor blood supply indicated during operation were replaced by other free flaps. Among 73 flaps with vascular crisis, 31 flaps were salvaged by surgical exploration and subcutaneous injection of low molecular heparin calcium. Obesity, smoking, preoperative radiotherapy and surgeon's experience, rather than age, hypertension and diabetes, were the risk factors of skin flap necrosis. Two-vein anastomosis had a higher success rate than one-vein anastomosis.

CONCLUSIONSThe necrosis rate of free flaps can be reduced by the choice of suitable flaps, subtly preparation of flaps, carefully vascular anastomosis, and prompt perioperative managements. The two-vein anastomosis is recommended. Diabetes, hypertension and elderly patients are not the contraindications for free flap reconstruction.

Aged ; Free Tissue Flaps ; Head ; Head and Neck Neoplasms ; surgery ; Heparin ; Humans ; Necrosis ; etiology ; Postoperative Complications ; etiology ; Reconstructive Surgical Procedures ; Retrospective Studies ; Risk Factors ; Surgical Flaps