AIM:To investigate the expression of aryl hydrocarbon receptor (AhR) in atrial tissues of the patients with rheumatic heart disease (RHD), and the effects of AhR on rheumatic atrial fibrosis.METHODS:Right atrial specimens obtained from the patients with RHD requiring valve replacement surgery were divided into chronic atrial fibrillation (RHD+cAF, n=11) group and sinus rhythm (RHD+sinus rhythm, n=25) group.The patients with congenital heart disease (CHD) and sinus rhythm (CHD+sinus rhythm, n=12) who underwent heart surgery served as controls.The collagen volume fraction in the atrial specimens was examined by Masson`s trichrome staining.The protein expression and distribution of AhR, AhR nuclear translocator (ARNT) and CYP1A1 were detected by the methods of immunohistochemistry and Western blot.The mRNA expression of AhR, ARNT and CYP1A1 was detected by real-time fluorescence quantitative PCR.RESULTS:Compared with CHD+sinus rhythm group, the collagen content and the expression of AhR, ARNT and CYP1A1 were significantly increased in RHD+sinus rhythm group and RHD+cAF group.Compared with RHD+sinus rhythm group, the collagen content and the expression of AhR, ARNT and CYP1A1 were significantly increased in RHD+cAF group (P<0.05).CONCLUSION:The expression of AhR is correlated with the degree of fibrosis.The expression of AhR/ARNT/CYP1A1 is increased in atrial tissues of patients with RHD, suggesting that AhR/ARNT/CYP1A1 should be involved in atrial fibrosis of the patient with RHD.

Objective: To explore the clinical effects and key techniques of expanded super-thin perforator flaps in the shoulder, neck, and chest in reconstruction of extensive burn scars in the face. Methods: From January 2008 to November 2018, 22 patients with extensive burn scars in the face were admitted to the Department of Plastic Surgery of Dongguan Kanghua Hospital and the Department of Plastic Surgery of Dermatology Hospital of Southern Medical University, with 3 males and 19 females, aged from 4 to 48 years. There were 16 cases of type Ⅱ and 6 cases of type Ⅲ in facial scars. Before the first stage of expansion surgery, Doppler blood flow survey meter or multi-slice CT was used to locate the perforator vessels. One to four expanders with rated capacity ranged from 100 to 600 mL were placed in the patients. We gave 20% to 30% of the rated capacity of expander intro-operation and common injection with 10% to 15% of the rated capacity of expander per week post-operation until the volume reached 1.5 to 2.5 times of the rated capacity of expander during the past 3 to 4 months. At the second stage of surgery, the perforators were located again before surgery with the same method. The size of defects after the excision of facial scars ranged from 6 cm×4 cm to 18 cm×16 cm. With perforators used as nutrient vessels, narrow pedicle flaps or random flaps ranging from 6 cm×6 cm to 22 cm×18 cm were elevated as rotating or advancing to reconstruct the defects. The donor sites were sutured directly. Some of the flaps needed stage Ⅲ operation for cutting the pedicle. The survival of flaps, post-operation complications, and follow-up were assessed. Results: All flaps of 22 patients survived. All the donor sites were closed simultaneously. One patient underwent an additional surgery for 5 cm×4 cm necrosis on distal part of flap caused by subcutaneous hematoma. Two patients with epidermis blister on the flaps were healed by themselves after dressing change. Due to rapid expansion, blood capillary proliferation appeared on the central part of the flap in 3 cases, after slowing down the expansion speed properly, which had no impact on flap transfer. No ischemia or venous congestion phenomenon were observed in the other flaps. During follow-up of 5 to 48 months, the flaps of patients showed no significant bloated appearance, with good complexion and texture, and even could reproduce facial fine-grained expressions naturally. Conclusions For the reconstruction of extensive burn scars in the face, expanded super-thin perforator flaps can not only acquire large and thin flaps with high matching degree surface skin defect, but also reproduce facial fine-grained expressions. It is a simple and safe method which conforms to the facial aesthetic standard.