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Objective: To explore the effectiveness of the insulin‐like growth factor 1 receptor (IGF‐1R)/PI3K/AKT pathway in promoting the synthesis of the auricular chondrocyte extracellular matrix (ECM) using concentrated growth factor (CGF). Methods: Chondrocytes isolated from the remnant auricular cartilage of microtia patients were randomly divided into different experimental and control groups, then stimulated with a reagent. IGF‐1 released by CGF was quantified by enzyme‐linked immunosorbent assay. Glycosaminoglycan (GAG), proteoglycan, and type II collagen (COLAII) were examined by histological and immunohistological analysis. Expression levels of IGF‐1R, pIGF‐1R, PI3K, pPI3K, AKT, pAKT, COLAII, and Aggrecan were detected by western blot analysis technique and gene expression was tested by real‐time polymerase chain reaction. Results: CGF significantly stimulated the synthesis of COLAII and Aggrecan and increased the phosphorylation levels of IGF‐1R, PI3K, and AKT. Small interfering RNA IGF‐1 blocked ECM synthesis, COLAII and Aggrecan gene expression, and IGF‐1R/PI3K/AKT activation. Inhibitor AG1024 and LY294002 significantly inhibited ECM synthesis and the phosphorylation of IGF‐1R, PI3K, and AKT. Conclusion: CGF‐released IGF‐1 stimulates the synthesis of the auricular chondrocyte ECM via the IGF‐1R/PI3K/AKT signaling pathway. [ABSTRACT FROM AUTHOR]

Selective cementing technology has been used to exploit the carbonate reservoir, which has satisfied the needs of multistage reform and later stimulation of reservoir. External Casing Packer (ECP), which is the key tool to selective cementing technology, is discussed in this paper to explore its main failure causes during the selective cementing operation. Analysis of the bottom hole temperature, running-in influencing factors, sealing position diameter and pipe string structure shows that rubber tear strength reduced by higher bottom temperature, unsmooth running-in influenced by oversized hole curvature, intensified friction during running-in induced by incompetent drifting measure, loading capacity reduced by oversized sealing position diameter and unreasonable pipe string structures, and non-effective protection to the ECP are the main causes of the ECP failure. According to the failure causes above, corresponding technical measures have been established: the actual maximum operating temperature is rated operating temperature multiplying by a safety factor; using the effective technical measures to control the borehole curvature; simulating drifting with the watermelon mill; choosing the rational borehole diameter of the sealing up position and connecting short casing fitted with centralizer at both ends in the ECP. These measures are significant for reducing the possibility of ECP failure and improving the safety reliability of selective cementing technology. [ABSTRACT FROM AUTHOR]

Objective: To discuss the effects of the temporoparietal fascial flap and the postauricular fascial flap as the materials to cover the postauricular-frame during the second stage operation of the total auricular reconstruction., Methods: From June 2005 to May 2007, the second stage elevation of the reconstructed auricle was performed at 6-10 months after the first stage total auricular reconstruction for 72 cases (left 31, right 41), 47 males and 25 females, aged 5-28 years old (12 on average). According to the Nagata's classification, 56 cases were lobule-type microtia with no external auditory canal, and the other 16 cases were concha-type microtia with external auditory canal (narrow in 9 cases). Homolateral temporoparietal fascial flap was used to cover the postauricular-frame in 29 patients (group A), and the homolateral postauricular fascial flap was used in the other 43 patients (group B)., Results: All the patients were followed up for 3-22 months. A total of 55 cases had excellent skin flap and fascial flap (22 in group A and 33 in group B). Darker epidermis could be seen in 15 cases (6 in group A and 9 in group B), and it healed within one month after the operation. Two cases (1 in group A and 1 in group B) suffering from partial grafted skin and fascial flap necrosis (< 1 cm2) healed by means of coverage of local flap transfer. All the patients' reconstructed auriculocephalic angles were close to the normal side. There existed scars of varying degrees at the area of skin graft in both groups: 47 cases had flat scars (19 in group A and 28 in group B); 18 cases had hyperplastic scars (7 in group A and 11 in group B); and 7 cases had severe scars with the auriculocephalic angles draw-off (3 in group A and 4 in group B). Furthermore, there were obvious scars in temporal region and severe hair thinning at the donor site in group A, but there were no such conditions in group B. At 6 months of follow-up, reduction of the auriculocephalic angle occurred in 3 cases of group A and obvious in 5 cases of group B (> 0.5 cm)., Conclusion: Both the temporoparietal fascial flap and the postauricular fascial flap can be applied to cover the postauricular-framework in the second stage reconstructed ear elevation, with superiority of the latter over the former.

Objective: To explore an effective method to repair penile-scrotal or perineal hypospadias in one stage with prepuce island flap., Methods: Different prepuce island flaps were designed according to the different pathological anatomy of the penile-scrotal or perineal hypospadias. The prepuce island flaps were thus translocated and sutured to form the urethra. Thirty-one cases of hypospadias (21 cases of peinil-scrotal type, 10 cases of perineal type) were repaired with prepuce island flap. The biggest length and the width of the prepuce island flap were 7.5 cm and 1.5-1.8 cm respectively., Results: All the cases resulted in a good contour of the penis and a normal anatomic position of urethral meatus without any redundancy or tortuosity. The urination was perfect and acceptable., Conclusion: One stage repair of penile-scrotal or perineal hypospadias with prepuce island flap can be considered as an acceptable effective surgical technique.