[Efficacy of ibutilide for cardioversion of persistent atrial fibrillation during radiofrequency ablation].

OBJECTIVE: The aim of this study was to investigate the efficiency and safety of ibutilide for cardioversion of persistent atrial fibrillation (AF) during radiofrequency ablation. METHODS: Eighteen patients (16 males) with persistent atrial fibrillation were enrolled in this study. All patients underwent circumferential pulmonary vein ablation guided by a Carto three-dimensional mapping system. In addition, linear ablation at the top of the left atrium and the isthmus of mitral valves and complex fractionated atrial electrogram (CAFE) ablation were performed. All patients were still in either atrial fibrillation or atrial flutter after ablation, the patients were treated with 1 mg intravenous ibutilide injection within 10 minutes after unsuccessful ablation. Intravenous injection was stopped in case of sinus rhythm (SR) restoration or occurrence of severe adverse reactions such as ventricular tachycardia. Cardioversion rate within 30 min and adverse reactions within 4 h were observed. Patients were divided into either conversion group or non-conversion group according to whether AF was converted to sinus rhythm within 30 minutes after injection. RESULTS: Eleven patients (61.11%) converted to SR after ibutilide injection. There were no significant differences in gender, age, body mass index, left atrium and left ventricular function between conversion group and non-conversion groups. The average conversion time was (13.80 ± 7.64) min, left atrium scar area ratio was significantly larger in non-conversion group (12.40 ± 11.03)% than in conversion group (5.12 ± 3.83)%, P < 0.05. Ibutilide significantly prolonged the average wavelength of the AF wave (171.8 ± 29.5) ms vs. (242.0 ± 40.0) ms at baseline, P < 0.01. The QT interval at 30 min after ibutilide injection (0.39 ± 0.21) s was significantly longer than before injection (0.51 ± 0.08) s, P < 0.05. There was no serious arrhythmias or other adverse reactions post ibutilide injection. CONCLUSIONS: Ibutilide is highly effective and safe agent for cardioversion in patients underwent unsuccessful ablation. Left atrium scar area ratio is an important determinant for the conversion rate in this cohort.

A double-spliced defective hepatitis B virus genome derived from hepatocellular carcinoma tissue enhanced replication of full-length virus.

In hepatitis B virus (HBV) replication cycle, pregenomic RNA undergoes splicing and the reverse transcribed defective genomes can be packaged and released. Various types of spliced defective HBV genomes have been isolated from the sera and liver tissues of viral hepatitis B patients. To explore the functions of a 2.2 kb double spliced HBV variant, a 3.2 kb full-length HBV isolate (#97-34) and its 2.2 kb double-spliced HBV variant (#AP-12) from the tumor tissue of a patient with hepatocellular carcinoma (HCC) were amplified and cloned. Sequencing results showed that #AP12 had deletions in pre-S2, part of pre-S1, S genes, part of the spacer, and part of the reverse transcriptase gene, while the X gene was intact. When this defective double-spliced genome and its full-length counterpart genome were co-transfected into HepG2 cells, the former was shown to enhance the replication of the latter, both by real-time PCR and Southern blotting. When a replication incompetent clone 97-34G1881A was used to co-transfect with #AP12, #AP12 DNA was increased, indicating that replication of the wild-type virus was not the only factor involved in this observation. However, the replication enhancing competency of #AP12 was shown to require an intact HBV X expression cassette. The double-spliced defective variant might contribute to persistent HBV replication in a subpopulation of HCC patients.

[Correction of secondary lip whistle deformities and nasal base depression after bilateral cleft lip repair with lip subdermal soft tissue flap].

OBJECTIVE: To explore a new method to correct secondary lip whistle deformities and nasal base depression after bilateral complete cleft lip (BCCL) repair with lip subdermal soft tissue flap. METHODS: Bilateral subdermal soft tissue "C" flaps and "lambda" flap were designed to repair secondary deformities of nasal base and reconstruct vermilion tubercle in patients after BCCL repair. RESULTS: Good results were achieved in all the patients with primary healing. No flap necrosis happened. The result was satisfactory. CONCLUSIONS: With bilateral subdermal soft tissue "C" flaps and " lambda" flap, nasal base depression deformities and lip whistle deformities can be corrected. It is an ideal method for correction of deformities after BCCL repair.

[Preliminary study on the phenomenon of epidermal stem cell ectopy in expanded skin].

OBJECTIVE: To observe the differentiation and distribution of epidermal stem cell (ESC) after skin soft tissue expansion, and to initially probe into the growth mechanism of expanded skin tissue. METHODS: Samples of normal skin and expanded skin (mean effusion period 45 days) were harvested from head and cervical region in 15 patients who underwent II stage surgery after skin expansion. Samples were divided into scalp adjacent to the center of expander group (expanded scalp, 3 cm from the vertical axis of the expander), scalp from lateral part of the expander group (expanded scalp, 5 - 7 cm lateral to the vertical axis of the expander), cervical skin expansion group, un-expanded scalp control group, and un-expanded cervical skin control group, according to the position of skin harvested. The tissue structure of skin in each group was observed with HE staining, and the differentiation and distribution characteristics of cytokeratin 19 (CK19) positive cells were observed with immunohistochemical staining. RESULTS: Compared with those in the un-expanded control groups, uneven, relatively thickened and obviously folded epidermis with more cell layers and cells with obvious aggregation close to the basal layer were observed in the expanded groups, but those cells were not well-arranged and the transition of polarity was not obvious. The continuity of CK19 positive cells in the basal layer of skin was observed in each of the expanded group with immunohistochemical staining, and positive cells increased obviously and arranged in multilayer in certain parts of basal layer. Clustered or dispersed CK19 positive cells were also observed outside the basal layer. No above-mentioned phenomenon was observed in the un-expanded control group. CONCLUSIONS: The proliferation and differentiation of ESC with ectopic distribution may enhance the repair process after skin soft tissue expansion.

Proteomic analysis of hepatitis B surface antigen positive transgenic mouse liver and decrease of cyclophilin A.

The small, 22-nm spherical particles associated with hepatitis B infection are composed of hepatitis B surface antigen (HBsAg) and usually outnumber the virions by a ratio of 10(2) or 10(3). To study the interactions and pathogenesis between liver cells and the expression of HBsAg, global protein profiles were compared by two dimensional gel-based differential proteomics between the livers of a lineage of HBsAg positive transgenic mice and their HBsAg negative control siblings. A total of 93 proteins were identified in the HBV transgenic mice. Around 45% of these differentially expressed proteins were enzymes associated with metabolism, suggesting that the processing of lipids, carbohydrates and certain amino acids were up- or down-regulated. Among these proteins, cyclophilin A (CypA), the major target for the potent immunosuppressive drug cyclosporin A, was found decreased in HBsAg positive transgenic mouse liver and in a stable cell line expressing HBsAg when compared to their controls. The decrease of intracellular CypA was accompanied by an increased secretion of this protein into the supernatant of HBsAg positive cells. Possible implications of HBsAg expression and the intracellular decrease of CypA are discussed.

[The applications of the repetitive sub-platysmal expansion in repair the defects of skin and soft tissue in face and neck].

OBJECTIVE: To study a new effective approach which repairs large defects of skin and soft tissue in neck and face. METHOD: This procedure accomplishes repetitive sub-platysmal expansion to form large musculocutaneous flap with underlying pedicel. The surgeon slides it toward neck and face to repair the defects of skin and soft tissue. RESULT: Eleven patients, who had such defects in neck, face, cheek, chin or submental skin and soft tissue, underwent this treatment. All the flaps survive with no complications of blood supply deficiency or necrosis. The short-term and long-term results are both satisfying. CONCLUSION: This method, making repetitive sub-platysmal expansion to form musculocutaneous flap and then slide it toward neck/face to repair large defects of skin and soft tissue, proves to be safe and reliable. And appropriate cases and strict operations are important.