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Featured researches published by Yong-zhong Mao.


Journal of Pediatric Surgery | 2011

Laparoscopically assisted anorectal pull-through for high imperforate anus in infants: intermediate results

Qiangsong Tong; Shao-Tao Tang; Jiarui Pu; Yong-zhong Mao; Yong Wang; Shiwang Li; Quo-qing Cao; Qing-Lan Ruan

PURPOSE The aim of this study was to evaluate the clinical outcomes and postoperative anal function in infants with congenital high imperforate anus treated with laparoscopically assisted anorectal pull-through (LAARP). METHODS From January 2004 to July 2007, 33 patients (28 boys and 5 girls, age ranging from 3 to 10 months) with high imperforate anus underwent LAARP. Clinical data of the LAARP group were retrospectively compared with those treated by posterior sagittal anorectoplasty (PSARP; n = 28) during the same time period. Anorectal function of these patients was evaluated using the following 3 methods: the Kelly score, anorectal vector volume manometry, and magnetic resonance imaging between the ages of 3.1 and 4.4 years. RESULTS The mean operative time in LAARP and PSARP groups was 112.5 ± 12.4 and 120.4 ± 18.5 minutes (P > .05), respectively. The mean length of hospital stay in the LAARP group was shorter than that of PSARP group (11.3 ± 2.1 vs 14.6 ± 2.3 days, P < .01). No significant difference was observed between LAARP and PSARP groups regarding the Kelly score (3.52 ± 1.42 vs 3.49 ± 0.82). Although magnetic resonance imaging revealed lower malposition rates of rectum in the LAARP group than those of the PSARP group at both I-line (3.0% vs 14.3%) and M-line (3.0% vs 10.7%) levels, this was not statistically different (P > .05). Compared with the PSARP group, lower asymmetric index, larger vector volume, and higher anal canal pressure at rest and during voluntary squeeze were observed in LAARP group (P < .05). However, there were no significant differences in the length of high-pressure zone (15.2 ± 5.8 vs 15.1 ± 6.2 mm) and the presence of rectoanal relaxation reflex (84.8% vs 85.7%). CONCLUSIONS Satisfactory fecal continence can be achieved in patients with high-type imperforate anus after LAARP. Laparoscopically assisted anorectal pull-through has advantages over PSARP, including shorter hospital stay and better position of rectum. However, long-term follow-up is necessary to compare the benefits of LAARP against PSARP.


Journal of Laparoendoscopic & Advanced Surgical Techniques | 2012

10 years of experience with laparoscopic-assisted endorectal Soave pull-through procedure for Hirschsprung's disease in China.

Shao-tao Tang; Guo-bin Wang; Guo-qing Cao; Yong Wang; Yong-zhong Mao; Shiwang Li; Shuai Li; Ying Yang; Jun Yang; Li Yang

OBJECTIVE To report early and late results of laparoscopic-assisted endorectal Soave pull-through (LAEPT) with a short and V-shaped partial resection muscular cuff for Hirschsprungs disease (HD) over a 10-year period. METHODS The clinical courses of 218 patients who underwent modified LAEPT for HD were reviewed. LAEPT was described by the Georgeson technique. The main modifications included less dissection of the bottom of the pelvis, rectal mucosa dissection with a long cuff, coloanal anastomosis with a short cuff, and a V-shaped partial resection in the posterior wall of the muscular cuff. RESULTS From September 1999 to July 2009, 218 patients were operated on by the same surgeon. Ages ranged from 15 days to 12 years old. The aganglionic segment was located in the rectum or sigmoid colon in 176 patients, in the left colon in 38 children, and in the transverse colon in 4 patients. The median operating time was 176 minutes. Conversion to open surgery was required in 2 patients. Bleeding of the left iliac vein occurred in 1 patient, and a 180° twist of the neorectum occurred in 2 cases. Median first bowel movement time was 23 hours, and median postoperative hospital stay was 10.4 days. Median daily defecation frequency was 4.6 within 2 weeks and 2.3 at 3 months postoperatively. The immediate postoperative complications included intestine herniation from the trocar site in 2 patients, perianal excoriation in 32 patients, and anastomotic leakage in 3 patients. Follow-up ranging from 6 to 120 months was obtained for 182 patients. Late postoperative complications included postoperative adhesive bowel obstruction (1.1%), enterocolitis (7.7%), anasomostic stenosis (2.2%), constipation (1.6%), and soiling (3.6%). Eighty-seven percent had excellent and good bowel function. CONCLUSION LAEPT with a short muscular cuff with a V-shaped partial resection in the posterior wall is a safe and effective procedure for HD.


World Journal of Pediatrics | 2010

Laparoscopic extensive colectomy with transanal Soave pull-through for intestinal neuronal dysplasia in 17 children

Shao-Tao Tang; Ying Yang; Guo-bin Wang; Qiangsong Tong; Yong-zhong Mao; Yong Wang; Shiwang Li; Qing-Lan Ruan

BackgroundOpen colectomy has been preferred for intestinal neuronal dysplasia type B (IND) due to its low morbidity rate and good functional results. The aim of this study was to investigate the feasibility and results of laparoscopic colectomy with transanal Soave pull-through for the treatment of IND in children.MethodsSeventeen infants and children suffering from IND were treated by laparoscopic extensive colectomy with transanal Soave pull-through. The diagnosis of IND was made via anorectal manometry, X-ray contrast enema, suction biopsies, and laparoscopic full-thickness biopsies with hematoxylin-eosin staining. The technique used four or five abdominal ports. The sigmoid, transverse, and right colon up to the last ileal cove were mobilized laparoscopically in the extended form of IND. A modified Soave’s anastomosis was performed. The patients’ data, surgical procedures, operative data, postoperative complications and clinical outcomes were analyzed.ResultsFive patients underwent laparoscopic left colectomy with modified transanal Soave procedures, and the other 12 were treated by laparoscopic subtotal colectomy and required a Deloyers’ maneuver for the Soave pull-through. The proximal margin of barium stagnation in patients with left colectomy was restricted to the distal end of the descending colon, sigmoid colon, and that in patients with subtotal colectomy was restricted to the proximal end of the descending colon, transverse colon, hepatic flexure, and ascending colon. Postoperative complications included anastomotic leakage, severe perianal erosions, postoperative enterocolitis, and soiling. During a mean follow-up of 4 years, bowel frequency was 4–10 times per day in 3 months postoperatively in patients with subtotal colectomy. The clinical results were good, with no stool incontinence or constipation.ConclusionsLaparoscopic procedure for left colectomy and subtotal colectomy with transanal Soave pull-through in infants and children with IND is safe, feasible, and effective. The location of barium stagnation in proximal margin may be used as a method to predict initially the proximal margin of the resected bowel segment.


Journal of Pediatric Surgery | 2009

Clinical value of pelvic 3-dimensional magnetic resonance image reconstruction in anorectal malformations

Shao-Tao Tang; Guo-qing Cao; Yong-zhong Mao; Yong Wang; Shiwang Li; Ying Yang; Qiang-Song Tong

OBJECTIVE The study aimed to build a 3-dimensional (3D) reconstruction of pelvic magnetic resonance images and evaluate the clinical value in anorectal malformations (ARMs). METHODS Magnetic resonance imaging (MRI) examinations were performed on a 1.5-T magnet. Sagittal, coronal, and transverse turbo spin-echo T1-weighted and fast spin-echo T2-weighted images of the pelvic region were obtained in 22 children. A 3D reconstruction was made on a computer and assisted by the 3D-Doctor software (Trial Version, Able Software Corp). The level and type of ARM and the developmental state of the striated muscle complex (SMC) were analyzed with 3D reconstruction image. RESULTS The 3D images of the pelvic were confirmed in 22 cases. Three-dimensional reconstructed images perfectly displayed the anatomical relationships of the SMC and the rectal atresia in these spaces. The 3D configuration of the SMC was different in each of the high- and low-type cases. The high-type malformation of SMCs differed particularly from the descriptions. CONCLUSIONS Pelvic magnetic resonance 3D reconstructed images were able to show the dimensional anatomical relations of pelvis, bladder, urethra, rectum, and SMC. Both a 3D image and positional information with MRI offers the surgeon a simulated operative profile of the SMC superior to MRI slices alone, which will help in providing morphological data for image diagnosis and operation of the ARM.


Journal of Pediatric Surgery | 2009

Laparoscopy-assisted orchiopexy for recurrent undescended testes in children ☆

Qiang-Song Tong; Li-Duan Zheng; Shao-Tao Tang; Yong-zhong Mao; Yong Wang; Yuan Liu; Jia-Bin Cai; Qing-Lan Ruan

OBJECTIVE Reoperative orchidopexy is a technical challenge to pediatric surgeons. The laparoscopy-assisted procedure is described for securing the testis in the scrotum in patients with a past history of open orchidopexy and testes in an unsatisfactory position. PATIENTS AND METHODS Thirty-one patients with 35 abnormally positioned testes (4 bilateral) were evaluated. All patients had a past history of inguinal surgery, and ages ranged between 2.5 and 13 years (mean, 5.5 years). Previous surgical procedures included 32 orchiopexies and 3 testicular detorsion of undescended testis. If needed, inguinal dissection was performed to loose the adherence between the cord and inguinal canal. Laparoscopic orchidopexy was applied to allow the testis to remain in the scrotum without tension. Patients underwent follow-up every 3 months after the operation with physical and ultrasound examinations. RESULTS Ten low inguinal testes were treated directly with open inguinal redo orchidopexy, whereas laparoscopy-assisted orchidopexy was possible in 23 (92%) of the remaining 25 reoperations. In 2 (8%) of these cases, severe scarring was present between the cord and the inguinal canal impeding the laparoscopy-assisted orchidopexy. For laparoscopy-assisted procedure, the operation time was 42 to 67 minutes (mean = 52 min). After the laparoscopy-assisted reoperations, 23 (92%) testes remain within the scrotum after a mean follow-up of 22 months (range, 6-32 months). CONCLUSION When feasible, laparoscopy-assisted orchiopexy is a simple and effective technique for securing testicles in reoperative orchiopexy procedures.


World Journal of Pediatrics | 2009

Nuss operation for pectus excavatum: a single-institution experience

Yong-zhong Mao; Shao-Tao Tang; Yong Wang; Qiang-Song Tong; Qing-Lan Ruan

BackgroundThe Nuss procedure for repair of pectus excavatum (PE) has been accepted worldwide because of minimal invasiveness and excellent cosmetic results. We summarized our experience with the treatment of 115 patients aged 2.7–18 years.MethodsAll the 115 patients underwent the Nuss procedure successfully from July 2003 to February 2008. They were divided into two groups: children group (below 12 years) and adolescents group (aged 12–18 years).ResultsThe rate of complications was 14.7% and 37.5% in the children and adolescents groups, respectively (P<0.05). There was significant difference in operation time, length of hospital stay, and analgesic time between the two groups (P<0.05). The initial results of Nuss procedure were excellent.ConclusionsThe Nuss procedure can be performed with excellent early results in children. We suggest that children with PE should accept the Nuss procedure as early as possible when they are over 5 years old.


Journal of Pediatric Surgery | 2010

Endoscopic transaxillary approach for congenital muscular torticollis

Shao-Tao Tang; Ying Yang; Yong-zhong Mao; Yong Wang; Shiwang Li; Qiangsong Tong; Guo-qing Cao; Shuai Li

BACKGROUND Surgical correction of the congenital muscular torticollis (CMT) is recommended for patients with unsuccessful conservative treatment. Open operative techniques all leave noticeable scars. We proposed a modified endoscopic 1-trocar transaxillary and neck microincision approach for the treatment of CMT. METHODS Endoscopic release of the sternocleidomastoid (SCM) muscle was performed in 45 infants and children aged 6 months to 15 years. One 5-mm incision was made in the anterior axillary fold, and a subcutaneous tunnel over the clavicular and sternal heads of the SCM muscle was made. A subcutaneous space was established by CO₂ inflation at a pressure of 8 mm Hg and then endoscopically using a 5-mm endoscope. Two additional 1.5- to 2-mm supraclavicular mini-incisions were made beside the SCM muscle for the introduction of miniforceps and electrocautery, respectively. The sternal and clavicular attachments were dissected and divided by electrocautery. Clinical evaluation was performed using the Lee scoring system. RESULTS The operation was successfully completed endoscopically in all 45 children. The mean operative time was 40 minutes. No injuries of major blood vessels or nerves were encountered. A small bleed was noted in 1 child owing to reoperation. Follow-up for 6 months to 3 years in 42 patients showed complete muscular release and satisfactory cosmetic appearance with no recurrence. The results were classified as excellent in 88.1% (37/42), good in 9.5% (4/42), fair in 2.4% (1/42), and poor in 0 using the Lee scoring system. The neck scars were not visible 1 month after the procedure. CONCLUSIONS The subcutaneous endoscopic transaxillary and micro-neck incision approach for the treatment of CMT is a safe, practical procedure that provides good functional and cosmetic outcomes without vascular or neural injury.


World Journal of Pediatrics | 2008

Expression of matrix metalloproteinase 1 and 2 in congenital choledochal cyst and its clinical significance

Yong-zhong Mao; Shao-Tao Tang; Qing-Lan Ruan

BackgroundThe pathogenesis of congenital choledochal cyst (CCC) is still not well elucidated. This study was conducted to detect the expression of matrix metalloproteinase-1 and 2 (MMP-1 and MMP-2) in CCC. The roles of MMP-1 and MMP-2 in CCC formation were also discussed.MethodsSpecimens of CCC and gallbladders were taken from 53 patients with CCC, including 21 boys and 32 girls aged from 4 months to 17 years (mean: 6.5 years old). Twenty-eight normal gallbladders served as controls. Immunohistochemical method was used to detect the expressions of MMP-1 and MMP-2. Image analysis was made to quantitatively analyze the protein expression.ResultsThe expressions of MMP-1 and MMP-2 were located in epithelial cells, matrix cells, and inflammatory cells of the CCC wall. Various expressions were also found in the mucosa membrane cells of the CCC gallbladder. The expressions of MMP-1 and MMP-2 were low in the control group. Quantitatively, the expressions of MMP-1 and MMP-2 in the CCC wall were markedly higher than in the CCC gallbladder and the control group (P<0.01). There was no significant difference between the CCC gallbladder and the control group (P>0.05).ConclusionsThe expression of MMP-1 and MMP-2 in the CCC wall is higher than in the CCC gallbladder and controls. The over-expression of MMP-1 and MMP-2 may be involved in the pathogenesis of CCC.


Journal of Pediatric Surgery | 2017

Duhamel operation vs. transanal endorectal pull-through procedure for Hirschsprung disease: A systematic review and meta-analysis

Yong-zhong Mao; Shao-tao Tang; Shuai Li

OBJECTIVE To compare treatment outcomes in children with Hirschsprungs disease who underwent treatment using the Duhamel or TERPT surgical procedures. METHODS Medline, Cochrane, EMBASE, and Google Scholar databases were searched through December 26, 2016. Search strings included Hirschsprungs disease, fecal incontinence, transanal endorectal pull-through, and Duhamel operation. Randomized controlled studies (RCTs) and retrospective studies that compared the treatment of Hirschsprungs disease in with TERPT or Duhamel surgical procedures in neonates, infants, or children were included. RESULTS The study included six studies with a total of 280 patients. The meta-analysis indicated that the Duhamel and TERPT interventions were similar with respect to rate of postoperative fecal incontinence (OR=0.85, 95% CI=0.37 to 1.92, P=0.692) and operation time (difference in means=46.68min, 95% CI=-26.96 to 114.31, P=0.226). The Duhamel procedure was associated with longer postoperative hospital stay (Difference in means=3.14days, 95% CI=1.46 to 4.82, P<.001) and a lower rate of enterocolitis (OR=0.21, 95%=0.07 to 0.68, P=0.009) compared with the TERPT procedure. CONCLUSIONS The study found that Duhamel and TERPT procedures showed similar benefit in treating Hirschsprungs disease, although differences exist with respect to length of postoperative hospital stay and the incidence of enterocolitis. THE TYPE OF STUDY Meta-analysis. LEVEL OF EVIDENCE Level II.


Cellular Physiology and Biochemistry | 2018

Inhibition of the Notch Signaling Pathway Reduces the Differentiation of Hepatic Progenitor Cells into Cholangiocytes in Biliary Atresia

Yong-zhong Mao; Shaotao Tang; Li Yang; Kang Li

Background/Aims: Viral infections, especially with rotavirus, are often considered an initiator of the pathogenesis of biliary atresia (BA). However, the mechanism by which rotavirus induces BA is still unclear. Methods: A BA mouse model was induced in newborn mice by i.p. inoculation with rhesus rotavirus within 6 h of birth. The expression of Notch pathway-associated molecules (JAG1, JAG2, Notch1, Notch2, Notch3, Notch4, DII1, DII3, and DII4) was measured by quantitative PCR and western blot analysis. Bile duct obstruction was detected by hematoxylin and eosin staining and CK-19 immunohistochemical staining. DAPT was used to inhibit the Notch pathway in vivo and in vitro. Results: In the livers of patients with BA and rotavirus-induced BA mice, the expression of JAG1 and Notch2 was significantly increased. Inhibition of the Notch pathway by DAPT in vivo ameliorated bile duct obstruction and delayed BA-induced mortality. The serum levels of inflammation cytokines (TNF-α, IL-2, IL-8, and IL-18) were reduced by inhibiting the Notch pathway. The expression of CK19, Sox9, and EpCAM was significantly increased in BA liver, while DAPT treatment decreased the expression of CK19, Sox9, and EpCAM. Conclusion: Notch activation is involved in the pathogenesis of BA by promoting the differentiation of hepatic progenitor cells into cholangiocytes.

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Yong Wang

Huazhong University of Science and Technology

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Shao-Tao Tang

Huazhong University of Science and Technology

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Shiwang Li

Huazhong University of Science and Technology

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Qing-Lan Ruan

Huazhong University of Science and Technology

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Guo-qing Cao

Huazhong University of Science and Technology

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Qiangsong Tong

Huazhong University of Science and Technology

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Ying Yang

Huazhong University of Science and Technology

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Shao-tao Tang

Huazhong University of Science and Technology

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Li Yang

Huazhong University of Science and Technology

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Shuai Li

Huazhong University of Science and Technology

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