Objective To summarize the experiences of diagnosis and treatment of dermatofibrosarcoma protuberans (DFSP). Methods The clinical data of 16 patients with DFSP were analyzed retrospectively. All the patients with DFSP underwent extensive tumor resection (3～5cm margin from the tumors).Free full-thickness skin flap transplantations was performed on 6 cases , three cases received skin flap shifting operations, and 1 patient with abdominal wall deficiency was repaired by artificial mesh . Results All the 16 patients presented as painless cutaneous nodules which enlarged slowly, but the majority of the tumors grew quickly in recent shorter time. Ten cases were primary tumors, and six were recurrence. The time of recurrence after surgery ranged from 3 months to 10.5 years with 1～3 times recurrence. There was no operative complications. Eleven patients were followed-up for 1～11 years and all survived,only one patient developed tumor local recurrence seven years after surgery. Conclusions A slowly enlarged painless cutaneous or subcutaneous nodules quickly growing in recent time is the clinical characteristic feature of DFSP. Extensive tumor resection is the treatment of primary DFSP.

Objective To explore the cause of and treatment for superior mesenteric artery syndrome (SMAS). Methods Clinical data of 21 patients from 1992 to 2002 with SMAS were analyzed retrospectively. Results Three cases of SMAS recovered with nonoperative treatments, eighteen recovered after surgical therapy including lysis and downward movement of the ligament of Treitz and extensive mobilization of the duodenum in 4 cases (Type Ⅰ), lysis and Roux-en-Y duodenojejunostomy in 9 cases (Type Ⅱ), side to side duodenojejunostomy in one (Type Ⅲ), and Billroth-Ⅱ gastrectomy in 2 cases (Type Ⅳ), and anterior side to side duodenojejunostomy or Roux-en-Y reconstruction in 2 cases (Type Ⅴ). Conclusion Correct diagnosis and appropriate surgery for SMAS lead to satisfactory outcomes.

Occult hepatitis B virus infection (OBI) is a special type of hepatitis B virus(HBV) infection in which the hepatitis B surface antigen (HBsAg) test is negative but the HBV nucleic acid test is positive. This article provides a review of the prevalence of OBI among blood donors, the likelihood of transmission, and recommendations of detection. The prevalence of OBI in blood donors varies between some countries in the world and representative regions in China. The analysis showed that the prevalence of OBI in blood donors is much higher in Africa than in the rest of the world, and the prevalence of OBI is higher among blood donors in the south of China than in the north. Blood donor with OBI has the possibility of transmitting HBV. Nucleic acid testing and hepatitis B core antibody detection are important in OBI screening for blood donors, and appropriate testing method should be selected according to the local HBV prevalence and economic situation, in order to minimise the impact of OBI on blood transfusion safety.

Objective:To study the serological and molecular biological characteristics and differences of occult hepatitis B infection (OBI) between blood donors and chronic hepatitis B (CHB) patients.Methods:Nineteen OBI samples from blood donors and Nineteen OBI samples from CHB patients were collected, and named as group A and group B, respectively. Chemiluminescence method was used for hepatitis B five items detection. Real-time PCR method was used for HBV DNA quantification, and S gene was amplified by nested PCR and sequenced by DNA sequencing.Results:The level of HBV DNA in group A was significantly lower than that in group B ( P<0.05), and there were no significant differences in the serological result between the two groups. The mutation rate in the " a" determinant of S gene in group B was significantly higher than that in group A ( P<0.05). Conclusions:Compared with CHB patients, OBI blood donors have lower levels of viral replication and less chance of S gene mutation, and the use of highly sensitive nucleic acid detection reagents and method during blood screening can maximize the safety of blood transfusion.

Objective:The serological characteristics and S gene sequencing of intermittent detection of hepatitis B virus (HBV) DNA from an unpaid blood donor were analyzed to provide a basis for correct interpretation of intermittent detection of HBV DNA from blood donors and better guarantee of blood safety.Methods:The samples of blood donors with intermittent detection of HBV DNA were collected for two blood donations. ELISA was used to detect HBsAg and NAT screening for HBV DNA. Electrochemical luminescence method was used to detect five items of hepatitis B. Nested PCR was used to amplify the HBV S gene, and gene sequencing was performed. Genotype and mutation were compared and analyzed.Results:HBsAg was negative in both samples by ELISA.NAT result were non-reactive once and reactive once. Hepatitis B e antibody (Anti-HBe) and hepatitis B core antibody (Anti-HBc) were positive. The same S gene sequence was obtained from two samples of the donor by amplification and sequencing, and the genotype was HBV genotype C. No mutation was found in the reference sequence comparison with S gene.Conclusions:The donor has occult HBV infection (OBI), which is manifested as intermittent detection by routine screening nucleic acid detection reagent, which is easy to miss HBV detection and seriously affects the safety of transfusion. Sensitive screening reagents and method are very important for the safety of blood transfusion.

Objective:To explore the application of nested PCR in the detection of occult hepatitis B virus infection (OBI) in blood donors, and improve the detection rate of OBI in blood screening before blood transfusion.Methods:From July 2021 to August 2022, 37 blood donors who donated blood in our center were found to have HBsAg- and nucleic acid testing (NAT)+ by serological tests and nucleic acid amplification tests. The CT value of nucleic acid amplification test was recorded, and the HBV DNA was quantitatively detected by fluorescent quantitative PCR; Conventional PCR primers and nested PCR primers were designed to amplify HBV S gene and pre-S gene using conventional PCR and nested PCR respectively, and gene sequencing was performed for the amplification result.Results:Among the 37 HBsAg- and NAT+ blood donors, 33 nucleic acid detection CT values were in the gray area, and the fluorescent quantitative PCR detection of HBV DNA value was negatively correlated with the nucleic acid detection CT value; 37 cases of HBsAg-, NAT+ blood donors could not be amplified by conventional PCR. After using nested PCR, 34 cases could detect the S gene of HBV virus, and 28 cases could detect the pre S gene of HBV virus; The amplified bands were all HBV genome bands by gene sequencing.Conclusions:The plasma HBV viral load of HBsAg- and NAT+ blood donors was very low; nested PCR has high sensitivity, which can improve the detection rate of HBV S gene and pre-S gene, and has certain application value for the pre transfusion screening and follow-up research of OBI.