Objective To investigate the diagnosis and treatment characteristics of pure red cell aplasia (PRCA)caused by human parvovirus (HPV)B19 infection after renal transplantation.Methods Two cases with PRCA caused by HPV B19-induced after renal transplantation,who were treated in the Department of Organ Transplantation,Nanfang Hospital,Southern Medical University,were summarized.Combined with literature review,the clinical characteristics,diagnostic method,course of treatment and prognosis of such disease were investigated.Results Two renal transplant recipients developed severe anemia early after transplantation with progressive deterioration and failed transfusion therapy.Other causes of anemia were ruled out and two patients were diagnosed as PRCA caused by HPV B19 infection according to bone marrow aspiration and biopsy as well as HPV DNA detection by fluorescent polymerase chain reaction (PCR).The symptoms of anemia were improved significantly after adjustment of immunosuppressive treatment protocol and intravenous immunoglobulin (IVIG).Conclusions For patients with unexplained and progressed anemia early after renal transplantation,especially those complicated with reticulocyte deficiency,the possibility of PRCA caused by HPV B19 infection shall be considered.The results of bone marrow aspiration and fluorescent PCR are the main bases for diagnosing PRCA.Immunosuppressive agents reduction and application of IVIG are the major treatment measures.Most of patients have great prognosis after treatment,but this disease is likely to recur.

Objective To conclude the experience of restoration of fat compartments volume intreatment of facial volume lost aging.Methods From May 2015 to May 2018,126 patients with facialvolume lost aging,aged from 34 to 52 years (mean age 42.6 years),were corrected by restoring fatcompartments volume using different sized autologous fat granule grafting technique.Patients' satis-faction was rated using Visual Analogue Scale (VAS) ranging from 1 (most unsatisfactory) to 10(most satisfactory).Results 126 patients with volume lost aging face were followed up from 3months to 2.5 years,the sculpted appearance became more fullness,the laxity,wrinkles and textureof skin were improved obviously,the patients' VAS score was (8.2±1.4).Conclusions Restorationof fat compartments by using different sized autologous fat granule grafting can augment the facicalfullness,reshape the facial contour and improve the aging skin.Therefore it proves to be a safe,multi-effecive and satisfying technique in the treatment of facial volume lost aging.

Objective:To design magnets to locate colorectal neoplasms based on magnetic tracer technology, and to test its feasibility and safety by animal experiments.Methods:The magnets used for endoscopic localization of colorectal tumors consist of a tracer magnet and a pursuit magnet, both of which are ring-shaped Nd-Fe-B magnets. Eight healthy Beagle dogs were used as animal models. Tumor locations were assumed in the different parts of the colon and rectum under colonoscopy. The tracer magnet was sent to the hypothetical tumors by endoscopic soft tissue clamp and fixed near the tumors. After 24 hours, laparoscopic surgery was performed under general anesthesia. The pursuit magnet was inserted near the resected colon or rectum through the main operating hole. The tracer magnet was absorbed to the pursuit magnet to identify the location of tumors.Results:The tracer magnet and pursuit magnet were successfully designed and processed. The suction force between the tracer magnet and the pursuit magnet at zero distance was 16 N. All the 8 Beagle dogs successfully received indwelling of magnets under colonoscopy, and no magnets fell off after 24 hours. After the placement of pursuit magnet under laparoscopy, the two magnets attracted each other rapidly and accurately, and successfully completed localization of tumor site without any damage during the operation.Conclusion:Colonoscopy combined with laparoscopy for colorectal neoplasms localization based on magnetic tracer technique is simple, accurate, safe and feasible.

Objective:To study the feasibility of establishing gastrointestinal anastomosis by magnetic compression technique in rabbits.Methods:Ten healthy New Zealand rabbits were selected as models for gastrointestinal anastomosis by magnetic compression technique. Daughter and parent magnets suitable for gastrointestinal anastomosis in rabbits were designed and manufactured. A daughter magnet was inserted into the stomach through the purse fistula in the lack of blood vessel area of gastric body, and was pushed into the duodenum along the intestinal tract. And then a parent magnet was inserted through the stomach fistula. The daughter and parent magnets were automatically attracted and pressed the gastric and intestinal walls after they were adjusted in the proper position. The stomach fistula was closed with purse string suture. After ischemia, necrosis, detachment of the tissues between magnets, gastrointestinal anastomosis was established, and the magnets and necrotic tissues were expelled together from the body through the digestive tract. Survival of experimental animals was observed. Anastomotic specimens were obtained one month after operation. The blasting pressure of anastomotic stoma was measured, and the healing of anastomotic stoma was observed with naked eyes.Results:According to the pre-designed operative route, 10 New Zealand rabbits all successfully completed the operation and survived one month after surgery. No complications occurred during perioperative period. The operation time was 35.80±4.71 min (range 28.00-43.00 min), and the magnet discharge time was 11.40±1.56 days (range 9.00-14.00 days). Anastomotic specimens were obtained one month after the operation. Gross observation showed that the anastomotic stoma of gastrointestinal bypass anastomosis healed well, and the surrounding tissues adhered slightly. The anastomotic bursting pressure was 103.00±7.95 mmHg (range 94.00-113.00 mmHg) (1 mmHg=0.133 kPa).Conclusion:The establishment of gastrointestinal anastomosis by magnetic compression technique in rabbits is simple and effective.

Objective To verify the feasibility and safety of stomach tumor marker localization based on magnetic tracer technique in dogs.Methods Six male Beagle dogs were examined by gastroscopy.Then tracer magnets were sent to the "tumor" locations assumed in advance and fixed near the "tumors" by endoscopic soft tissue clamp.Laparoscopic gastric tumor localization was performed under general anesthesia 24 hours later.The tracer magnet was placed near the tumor on the surface of the stomach through the operating hole after the conventional establishment of laparoscope puncture parallel mirror to explore the tracer magnet.After the two magnets were attracted,the location of the tracer magnet seen under the laparoscope was the location of the gastric tumor,so as to complete the labeling and positioning of the lesion.Results All the 6 Beagle dogs were successfully implanted with tracer magnets under gastroscopy.Twenty-four hours after the gastroscopy,the pursuit magnet was successfully implanted during laparoscopic surgery.The two magnets automatically attracted each other and formed a sandwich structure of "tracer magnet-gastric wall-pursuit magnet ",which completed the location and identification of gastric tumor under the laparoscopy.Conclusion Gastroscopy combined with laparoscopy based on magnetic tracer technique is simple,accurate,safe and feasible.