Embryonic stem cells undergo extensive self-renewal and have the capacity to differentiate along multiple cell lineages.Research on totipotency and directional differentiation of embryonic stem cells in order to treat intractable disease,such as cancer,heart failure,atherosclerosis by tissue regeneration and cell transplantation are investigated.Epigenetic modification,including DNA methylation,chromatin restructure,and non-coding RNA-mediated regulatory events,regulate the differentiation of embryonic stem cells without detectable genetic changes.These mechanisms are often associated with starting-up and maintenance of epigenetic silence.The achievement and focuses on the molecular mechanism of embryonic stem cells during directional differentiation regulated by epigenetic modification are reviewed.

Objective To statistically summarize the adverse reactions of anti-TB drugs treatment,to analyze the influencing factors of leucopenia and to compare the effect of Qijiao Shengbai Capsule and Leucogen Tablet in the treatment of leucopenia.Methods The adverse reactions in 840 TB patients diagnosed from September 2014 to November 2015 were statistically analyzed.The influencing factors of leucopenia were analyzed.Finally,the effect of Qijiao Shengbai Capsule(n=480) and Leucogen Tablets (n=360) for treating leucopenia.Results Clinicians paid less attention to routine blood monitoring (39.4 ％).Among adverse reactions,the damage of liver function had the highest incidence rate(abnormal liver enzymes 27.0％,increased bile acid 8.2％),followed by leukopenia [25.4％,mainly degree Ⅰ (16.9％)];female patients(P=0.000) and complicating liver damage(P=0.010) might be the risk factors of leukopenia.After treatment by two kinds of drug,white blood cells count was increased,the difference was statistically significant(P=0.000).Conclusion The occurrence rate of leucopenia is higher,females and liver function damage are easier to appear,so more attention should be paid to monitoring the blood routine in return visit.The two kinds of drug for treating leucopenia induced by anti-TB drugs have definite effect and could be used in clinic.

Objective To evaluate efficacy on treatment of acute iliofemoral lower extremity deep venous thrombosis with thrombectomy and pharmacological thrombolysis or pharmacological thrombolysis alone. Methods The clinical data of 175 cases of lower extremity iliofemoral deep venous thrombosis wereanalysed retrospectively. Patients were divided into thrombectomy group and thrombolysis group. There were 85 patients treated by thrombectomy, among these patients there were 46 with common iliac vein occlusion or stenosis. According to state of illness suitable treatment was selected, urokinase and low molecular weight heparin were given after operation. The other 90 patients were treated by pharmacological thrombolysis only,including urokinase and low molecular weight heparin. Results No significant differences were found in age, course of disease, swelling and associated diseases between the two groups before treatment (P ＜0. 05); After 1 month of treatment the circumference difference between bilateral limbs was reduced from (4.6±1.6) cm to (0.8 ±0.5) cm in operation group,and declined from (4.0±1.9) cm to (1.8 ±1.3) cm in thrombolysis group. The cure rate was 71.8% (61/85) in thrombectomy group and 38.9% (35/90) in thrombolysis group. 64.6% patients were followed up for an average of (28 ± 11 ) months.After 12 months of treatment the circumference difference between bilateral limbs was (0.4 ± 0.3 ) cm in thrombectomy group and ( 0.9 ± 0.7 ) cm in thrombolysis group respectively. The cure rate was 86.0% (49/57) in thrombectomy group and 53.6% (30/56) in thrombolysis group. In surgical group the incidence of deep venous thrombosis sequelae was less than in thrombolysis group( P ＜0. 05 ). The incidence of venous valve dysfunction in thrombectomy group was less than in thrombolysis group (P ＜ 0.05 ).Conclusions Thrombectomy and pharmacological thrombolysis was more effective than pharmacological thrombolysis alone in the treatment of acute iliofemoral deep venous thrombosis.

ObjectiveTo evaluate the mid- and long-term efficacy of subfascial endoscopic perforator surgery (SEPS)in the treatment CEAP classification C4 - C6 of primary chronic venous insufficiency(CVI). MethodsClinical data of 82 cases of chronic venous insufficiency were analysed retrospectively. According to operative method adopted,patients were divided into group A in which perforator veins were ligated under subfascial endoscopic surgery (SEPS group ),and group B in which perforator veins were not ligated (non-SEPS group).Diagnosis was established by clinical symptoms,color Doppler or ascending venography in all patients.Postoperatively patients were followed up regularly.The clinical outcomes between different surgicalmethods in two groups were assessed byCEAP clinical classification,CEAP clinical symptom scores,cumulative ulcer healing rate and cumulative ulcer recurrence rate.ResultsNo significant differences were found in CEAP clinical classification,CEAP clinical symptom scores between the two groups preoperatively ( P ＞ 0.05 ). There were significant differences in CEAP clinical classification such as edema,lipodermatosclerosis,venous ulceration between the two groups on 2 years postoperatively (P ＜ 0.05 ).The amount of swelling limbs,healed ulceration,active ulceration in group A was less than group B (P ＜ 0.05 ) on 3' and 5' years postoperatively.Significant differences were found postoperatively in total clinical symptom scores between group A and B.Clinical symptoms such as swelling,lipodermatosclerosis,ulcer healing in group A relieved more markedly than group B ( P ＜ 0.05 ).The median healing time of ulcers was 2.3 and 3.7 months respectively in group A and B.Log-rank test on group differences was sensitive to long-term cumulative ulcer healing rate ( x2 =4.063,P =0.044).But Breslow test on group differences was sensitive to early cumulative ulcer healing rate ( x2 =5.471,P =0.019).Cumulative ulcer healing rate in group A was significantly higher than in group B postoperatively (P ＜ 0.05 ).The cumulative ulcer recurrence rate in group A was significantly lower than group B (P ＜ 0.05).ConclusionsSuperficial vein resection combined with perforator vein ligation significantly enhanced clinical efficacy,accelerated ulcer healing and decreased mid- and long-term ulcer recurrence rate.

Objective To compare complication between clamp harmonic scalpel and traditional pattern of bipolar electric knife in open thyroidectomy.Methods Patients undergoing open thyroidectomy from Jan.2009 to Dec.2010 in Thyroid Surgery Department of Sun Yat-sen Memorial Hospital of Sun Yat-sen University were analyzed retrospectively.Patients fell into 2 groups according to operative pattern:633 cases in clamp harmonic scalpel group and 587 cases in bipolar electric knife group.Complications such as intraoperative and postoperative blood loss,reooperative hemostatic rate,transient or permanent recurrent laryngeal nerve palsy,transient or permanent hypocalcaemia,and infection rate were compared.Results Compared with bipolar electric knife group,intraoperative and postoperative blood loss,reoperative hemostatic rate,transient recurrent laryngeal nerve palsy and transient hypocalcaemia in clamp harmonic scalpel group were significantly lower:(21.0 ±0.7)ml vs (10.0±0.3) ml,(31.0±1.1) mlvs (12.0±1.4) ml,1.53％ vs0.47％,2.39％ vs0.95％,1.87％vs 0.63％,and 3.58％ vs 1.73％ respectively(P ＜0.05).There was no significant difference in complications of permanent hypocalcaemia,permanent recurrent laryngeal nerve palsy and infection rate for the 2 groups:0％ vs 0％,0％ vs 0％,and 0.68％ vs 0.63％ respectively ( P ＞ 0.05 ).Conclusions Compared with traditional pattern of thyroidectomy,complication rate in clamp harmonic scalpel is significantly lower.Thyroidectomy by clamp harmonic scalpel is a safer operative pattern and worth to be popularized.

ObjectiveTo discuss the management of chronic thyroid abscess in children. MethodsThe diagnosis and management of 16 children with chronic thyroid abscess admitted from Jul. 2007 to Jun. 2010 in Department of Thyroid Surgery of Sun Yat-ssn Memorial Hospital of Sun Yat-sen University were retrospectively analyzed. All the patients were checked by Doppler ultrasound. ResultsOf the patients, 6 were males and 10 were females. The time of onset was from 3.2 years to 8.5 years, with 4. 6 years as the median. Hypoechoic or mixed echoic lesions in thyroid were seen on Doppler ultrasound scan in all patients. Abscess was found on the left side of thyroid in 11 cases (68.8％), and on the right side in 5 cases (31.2％). Abscess in 12 cases (75％) occupied the whole thyroid and began encroaching the adjacent tissues. Hypodermic fistula was found in 7 cases (43.75％). 12 cases (75％) underwent part resection of thyroid gland, and 4 cases (25％) underwent total resection of thyroid gland and debridement. All patients recovered and no complication like vocal hoarseness occurred. No recurrence happened within the follow-up of 3 months to 5 years. ConclusionsThe effective diagnosis of chronic thyroid abscess in children is to perform Doppler ultrasound scan of thyroid gland before operation. Abscess and fistula resection, partial or total resection of the affected side of thyroid gland are needed. Wound drainage and postoperative antibiotc are also helpful.

Objective To investigate the causes of thyroid carcinoma reoperation and to explore the tim-ing, surgical pattern of reoperation .Methods The clinicopathologic data of 127 patients undergoing reoperation for differentiated thyroid carcinoma ( DTC) from Sep 2006 to Sep 2011 were retrospectively analyzed .Results The residual rate of first thyroid operation was 54.3%, and the lymphatic metastasis rate was 31.5%.The rate of temporary and permanent recurrent laryngeal nerve injury after reoperation was 3.1%(4/127)and 1.6%(2/127) respectively .The rate of temporary and permanent hypoparathyroidism was 4.7%( 6/127 ) and 0.8%( 1/127 ) respectively .No recurrence of thyroid carcinoma or metastasis of cervical lymph node was reported after reopera -tion during a follow-up of 6 months to 6years.Conclusions Reoperation should be performed according to the initial operative and pathological findings in DTC patients who underwent local resection .The rate of complication in the reoperation , recurrence of thyroid carcinoma and metastasis of cervical lymph node can be effectively re -duced in meticulous and experienced hands .

Objective To investigate activated nano carbon in prophylactic central lymph node dissection of T1 papillary thyroid non-microcarcinoma.Methods Patients with T1 papillary thyroid non-microcarcinoma in Thyroid Surgery Department of Sun Yat-sen Memorial Hospital of Sun Yat-sen University undergoing surgery from Jan.2012 to Jun.2013 were divided into 2 groups:odd numbers were the experimental group,and even numbers were the control group.Activated nano carbon was injected in the affected side of the thyroid in the experimental group.The lymph node metastasis,parathyroid function,and the rate of recurrent laryngeal nerve (RLN) injury were compared between the 2 groups.Results The total number of resected lymph nodes in the experimental group and the control group were 327 and 238 respectively.The positive lymph nodes in the experimental group and the control group were 120 (36.7％)and 56 (23.5 ％)respectively.The difference had statistical significance (P =0.000 85).The number of patients with lymphatic metastasis in the experimental group and the control group was 42 (56％) and 30 (40％) respectively.The difference had statistical significance (P =0.049 9).The average number of positive lymph node for patients in the experimental group and the control group was (2.86 ± 0.13) and(1.87 ± 0.09) respectively.The difference had statistical significance(P =0.009).The rate of transient hypoparathyroidism in the experimental group and the control group was 34.7％ and 60％ respectively.The difference had statistical significance (P =0.002).The incidence of hoarseness caused by RLN injury was 2.7％ and 4％ respectively in the experimental group and the control group.The difference had no statistical significance(P =1.000).Conclusions Activated nano carbon plays an important role in prophylactic central lymph node dissection of T1 papillary thyroid non-microcarcinoma phase.It not only contributes to lymph node dissection,but also protects parathyroid.However,it can't reduce the incidence of RLN injury.

Objective To investigate the extent of reoperation for patients of differentiated thyroid carcinoma(DTC) who require total thyroidectomy.Methods The data of 137 patients undergoing reoperation for DTC were analyzed.These 137 patients were firstly diagnosed as benigh tumors and underwent local resection in our department from June 2004 to June 2010,however,they were proved to be DTC by postoperative pathology.Results In the reoperation,78 cases received ipsilateral residual thyroid resection plus contralateral lobectomy,11 cases received contralateral lobectomy,4 cases received contralateral near total lobectomy,22 cases received bilateral remnant resection,15 cases received ipsilateral remnant resection plus isthmuscectomy,and 7 cases received contralateral remnant resection.46 cases received unilateral cervical lymph node dissection,and 15 cases received bilateral cervical lymph node dissection.The incidence of temporary and permanent recurrent laryngeal nerve injury was 2.9％ (4/137)and 0.7％ (1/137) respectively.The incidence of temporary and permanent hypoparathyroidism was 3.6％ ( 5/137 ) and 1.5％ (2/137) respectively.There was no clinical evidence of recurrence or cervical lymph node metastasis during the 6 months to 6 years of follow-up.Conclusions For DTC patients after local resection,reoperation methods should be selected according to the first operation and pathological results.Careful operation can effectively reduce complications and improve prognosis.

Objective To develop and validate a method for detecting factor 8 gene (F8) mutations in hemophilia A patients by Ion Torrent semiconductor sequencing .Methods Intron 22 and intron 1 inversions of F8 gene were identified by long distance PCR (LD-PCR), other mutations in the F8 gene were identified by Ion Torrent sequencing.Candidate variants were validated by Sanger sequencing .Sanger sequencing was applied to screen HA carriers from 11 female family members in the 8 pedigrees.One pregnant woman was offered prenatal diagnosis via analyzing the fetal DNA obtained through amniocentesis . Results Four missense mutations ( c.1331A >C, 1648C >T, c.6506G >A, c.6544C >T), two frameshift mutations ( c.2393 _2394insT, c.6320delG), one splicing mutation ( IVS5 +5G >A), one nonsense mutation (c.43C >T) and one Inv22 mutation were identified in all nine probands respectively . Among 11 female family members, 10 females were identified to be HA carriers, and one didn′t carry the maternal pathogenic mutation.Prenatal diagnosis result showed that the fetus inherited the wild -type maternal allele and was predicted to be unaffected by HA .Conclusion The targeted Ion Torrent sequencing is a reliable and efficient method to detect F8 mutations in patients with Hemophilia A disease .