[Clinical analysis of immunotherapy rechallenge in advanced gastric cancer].

Objective: To evaluate the efficacy and influencing factors of programmed death protein 1 (PD-1) monoclonal antibody rechallenge therapy in advanced gastric cancer (GC). Methods: The clinical data of patients with advanced GC who were treated with anti-PD-1 rechallenge in Henan Cancer Hospital from January 2020 to December 2021 were collected retrospectively. The progression-free survival (PFS) was defined as the time from the first or second used of anti-PD-1 treatment to the date of disease progression or the last follow-up, named PFS(1) and PFS(2), respectively. Kaplan-Meier method and Log rank test were used for survival analysis, Cox proportional hazard model was used to analyze the influencing factors. Results: A total of 60 patients with anti-PD-1 rechallenge therapy were collected, the median follow-up time was 12.2 months. The median progression-free survival (PFS(2)) of anti-PD-1 rechallenge therapy was 2.9 months, the objective response rate (ORR) was 16.7%, and the disease control rate (DCR) was 55.0%. The median PFS(2) of the first and second anti-PD-1 identical and different rechallenge treatment was 3.5 months and 1.9 months (P=0.007) respectively. The median PFS(2) of positive PD-L1 expression in rechallenge therapy was 3.4 months, ORR was 22.7%, and DCR was 63.6%; the median PFS(2) was 4.5 months, ORR was 27.3%, and DCR was 54.5% in patients with median PFS(1)≥6 months. Multivariate analysis showed that peritoneal metastasis was independently associated with anti-PD-1 rechallenge therapy with PFS(2) (HR=2.327, 95% CI, 1.066-5.082, P=0.034). The incidence of adverse reactions in grade 1-2 and grade 3-4 of anti-PD-1 rechallenge therapy was 83.3%, and 35.0%, respectively, and the safety was controllable. Conclusion: Rechallenge therapy with anti-PD-1 is a feasible treatment in advanced GC, but the screening of suitable population for rechallenge therapy still needs prospective data analysis and verification.

[Strategy of reoperation for pheochromocytoma and paraganglioma].

OBJECTIVE: To explore the surgical strategy and experience of reoperation for pheochromocytoma and paraganglioma which is very challenging. METHODS: The clinical data of 7 patients with pheochromocytoma and paraganglioma who underwent reoperation in Department of Urology, Peking University Third Hospital from August 2016 to February 2021 were analyzed retrospectively. There were 4 males and 3 females, with an average age of (44.1±11.5) years (28-60 years), 6 cases on the right side and 1 case on the left side. The causes of the operations included: (1) 2 cases of tumor recurrence after resection; (2) The primary operations failed to completely remove the tumors in 3 cases, because the tumors were large and closely related to blood vessels. (3) Pheochromocytoma and paraganglioma wasn't diagnosed before primary operation, therefore, drug preparation wasn't prepared. Two cases were interrupted by severe blood pressure fluctuations during the primary operations. Imaging evaluation, catecholamine biochemical examination and adequate adrenergic α receptor blockers were administrated in all the cases. The surgical approaches included open transperitoneal surgery in 4 cases, robot-assisted laparoscopy in 1 case and retroperitoneal laparoscopy in 2 cases. The innovative techniques included mobilization of the liver, inferior vena cava transection and anastomosis, and transection of left renal vein. RESULTS: The average tumor size was (8.0±3.2) cm (3.6-13.9 cm). The median interval between the reoperation and the primary operation was 9 months (IQR: 6, 19 months). The median operation time was 407 min (IQR: 114, 430 min) and the median blood loss was 1 500 mL (IQR: 20, 3 800 mL). Operations of 5 cases were performed successfully, and 1 case failed only by exploration during the operation. One case died perioperatively. There were 5 cases of intraoperative blood transfusion, the median transfusion volume of red blood cells was 800 mL (IQR: 0, 2 000 mL). One case experienced postoperative lymphorrhagia, and recovered after conservative treatment. The renal function was normal in 2 cases after resection and anastomosis of inferior vena cava or transection of left renal vein. The average postoperative hospital stay was (7.2±3.3) d (4-13 d). The median follow-up time of 6 patients was 33.5 months (IQR: 4.8, 48.0 months). The case who failed in the reoperation still survived with tumor and there was no recurrence in the rest of the patients. CONCLUSION: The reoperation of pheochromocytoma and paraganglioma, which can not be resected in the primary operation or recurred postoperatively, is difficult with high risk of hemorrhage, and there is a risk of failure and perioperative death. Different surgical approaches and strategies need to be adopted based on the different situation.

[Diagnosis and surgical treatment of massive adrenal area tumor with tumor thrombus].

OBJECTIVE: To summarize the experience of diagnosis and operation related to massive adrenal area tumor with venous tumor thrombus in clinic. METHODS: From October 2017 to March 2019, a total of 8 cases of massive adrenal area tumor (>7 cm) with venous tumor thrombus were admitted at Peking University Third Hospital including 5 males and 3 females with mean age 50.6 years (31-62 years). There were 6 cases on the right side and 2 cases on the left side. The first symptoms included abdominal discomfort, hypertension, Cushing syndrome and abnormal menstruation; special past history included cirrhosis and lung cancer. Computed tomography (CT) and routine endocrine hormone tests were examined. Preoperative imaging confirmed 5 cases masses with tumor thrombus in inferior vena cava (IVC) and 1 case with tumor thrombus in left renal vein. Two cases presented with tumor thrombus in central adrenal vein were found intraoperatively. Open adrenalectomy and thrombectomy were performed in 4 cases of right side complicated with high tumor thrombus of inferior vena cava. Laparoscopic adrenalectomy and thrombectomy were performed in 3 cases, including 2 cases on the right and 1 case on the left. The case with tumor thrombus in left renal vein gave up operation. The patients were followed up with outpatient and telephone. RESULTS: The mean size of the tumor was 8.9 cm (7-11 cm), the mean operative time was 319 min (120-510 min), while the estimated blood loss was 629 mL (50-1 200 mL). Intraoperative blood transfusion was required in 2 cases and 1 case encountered wound infection. The pathological types included pheochromocytoma, adrenocortical carcinoma, adrenal metastases of haptic carcinoma, and leiomyosarcoma. The case with left lung carcinoma who underwent left pneumonectomy one month before was highly suspected adrenal metastases of lung carcinoma. Tumor thrombus of pheochromocytoma was combined with blood thrombus. Capsule of adrenocortical carcinoma was fragile in adrenocortical carcinoma. Abundant blood supply existed in adrenal metastases. The leiomyosarcoma had unabundant blood supply and invaded IVC to form tumors thrombus. The mean follow-up time was 8.4 months (1-15 months). One case with adrenocortical carcinoma died after 1 year in the follow-up. CONCLUSION: We present the rare cases of different pathological types of massive adrenal tumors with tumor thrombus extending into the IVC extension or other vein. Preoperative diagnosis needs comprehensive evaluation and perfect preoperative preparation. Surgery is difficult and varied. Open approach as well as retroperitoneal laparoscopic approach is feasible.

[Retrospective study of diagnosis and treatment of renal oncocytoma].

OBJECTIVE: To summarize the experience of diagnosis and surgical treatment of renal oncocytoma, and to evaluate the surgical results based on follow-up results, in order to find the best strategy. METHODS: In the study, 21 cases with renal oncocytoma from December 2003 to April 2016 in Peking University Third Hospital were retrospectively analyzed, including 4 males, and 17 females, with 10 cases on the right side and 11 cases on the left side. Their age was between 15 to 80 years (average: 58 years). Ultrasound or CT examination after admission was conducted. Ultrasound examination showed solid nodules. CT manifestations were solid masses with enhancement, and the tumor size was between 1.5 cm to 6.5 cm (average: 3.3 cm). Of the 21 cases, 9 were located in the middle of kidney, 7 were located in the upper pole, and 5 were located in the lower pole. After preoperative examination, according to the size and location of the tumor, laparoscopic partial nephrectomy or laparoscopic nephrectomy was performed, respectively. RESULTS: All the operations were successful, in which 17 cases underwent laparoscopic partial nephrectomy (including 3 cases which were converted to open surgery), and 4 cases underwent laparoscopic radical nephrectomy. The operation time ranged from 75 to 274 min (mean: 144 min), and the blood loss ranged from 10 to 1 000 mL (mean: 115 mL). The postoperative hospital stay time ranged from 6 to 13 d (average: 8.2 d). The pathological results were all renal oncocytoma. In the study, 17 cases were followed up while 4 cases were lost to follow-up. The follow-up time ranged from 12 to 175 months (mean: 44 months). One case died in 20 months after operation with unknown reason, and there were no recurrence or metastasis in the other 16 cases. CONCLUSION: Renal oncocytoma is a benign tumor with good prognosis. Enhanced CT is an effective diagnostic method in assistant examination, but it is difficult to differentiate clear cell carcinoma only from the naked eye. It is worthwhile to measure CT value at different stages of the tumor by picture archiving and communication systems (PACS), and to compare with CT value of adjacent kidney tissue may improve the diagnostic efficiency of CT. Laparoscopic surgery is an effective treatment for renal oncocytoma. We recommend laparoscopic partial nephrectomy for the patients with renal oncocytoma as the best choice if conditions permit.

[Single-center study of laparoscopic radical nephrectomy with Mayo 0-2 level inferior vena cava thrombectomy].

OBJECTIVE: To investigate the safety and feasibility of laparoscopic treatment for renal carcinoma with Mayo 0-2 level venous thrombosis. METHODS: From January 2015 to February 2018, 58 renal carcinoma cases with venous thrombus underwent laparoscopic radical nephrectomy with inferior vena cava thrombectomy in Department of Urology, Peking University Third Hospital, of which, 51 cases were male, and 7 female, aged 29-82 years. According to the Mayo grade classification, 20 cases were level 0, 20 cases were level 1, and 18 cases were level 2, with left side being 22 cases, and right side 36 cases. The patients except for those complicated with hemorrhagic diseases, cardiac and pulmonary insufficiency, or those who could not tolerate anesthesia and surgical contraindications, underwent the operation after comprehensive examinations. RESULTS: The 58 cases of renal tumor with venous tumor emboli were successfully completed with the surgeries, including 50 cases of totally laparoscopic surgery, 8 cases of laparoscopy surgery from convert to open (among the patients who were converted to open surgery, 7 were complicated with grade 2 tumor thrombus and 1 with grade 1 tumor thrombus). The main reasons for converting to open surgery were huge tumors (the largest of which was about 16 cm in diameter), severe adhesion and difficulty of separation. For different patients, different surgical methods and procedures were adopted according to the tumor direction and the different grade of tumor thrombus. Radical nephrectomy combined with vena cava tumor thrombus removal was performed in 55 cases and segmental resection of vena cava in 3 cases. The operation time was 132-557 min, and blood loss was 20-3 000 mL. Post-operative pathological types: 51 cases were clear cell carcinoma, 5 cases were type 2 of papillary carcinoma, 1 case was squamous cell carcinoma, and 1 case was chromophobe cell tumor. In the study, 47 cases were followed up for 1-36 months, and 4 cases died (the survival time was 5-15 months, with an average of 10.2 months). CONCLUSION: Laparoscopic radical nephrectomy with inferior vena cava thrombectomy is a reasonable choice for renal tumor with Mayo 0-2 level venous thrombosis. For different tumor directions and different grades of tumor thrombus, an appropriate operation plan can give the maxim benefit to the patients with skillful surgeons.

[Retrospective study of young bladder urothelial carcinoma from a single center within 16 years].

OBJECTIVE: To evaluate the clinical and pathological features, treatment and prognosis for bladder urothelial carcinoma in relative young patients under 40 years. METHODS: A retrospective study involved a total of 43 consecutive patients of bladder urothelial carcinoma, which were under 40 years old from January 2001 to December 2016. RESULTS: The incidence rate of bladder urothelial carcinoma in the patients under 40 years was 2.2%, and 35 males and 8 females were included. The average age was 33 years (ranging from 23 to 40 years). At initial visit, 62.8% of the patients presented with painless gross hematuria, 9 patients were discovered by routine examination, and 7 patients experienced lower urinary tract symptoms. Solitary tumor occurred in 34 cases whereas multiple carcinomas had been discovered in 9 cases，and all the 9 multiple cases were from 31-40-year-old subgroups. All the patients received proper surgical intervention according to their own clinical stages. Post-operative pathological results showed 29 low-grade urothelial carcinoma and 14 high-grade cases which included 31 Ta cases, with 7 cases of T1, 1 case of T3, and 3 cases of T4 and one case of T1 plus Tis. The total follow-up was from 5 to 165 months, 3 cases were lost. The overall recurrence rate was 12.5% (5 cases from 40). One patient developed distal metastasis, one died of metastasis after 13 months, and the other three received secondary trans-urethral resection of bladder tumors. The average recurrence time was 39 months (ranging from 3 to 105 months). The progression rate was 5% among all the followed-up patients (2 cases from 40). The recurrence rate in multiple lesions group (33%, 3/9) was significantly higher than that (5.9%, 2/34) in solitary lesion group (P=0.000 3). CONCLUSION: The incidence rate of bladder urothelial carcinoma in young patients under 40 years becomes increasingly higher over years. The major initial presentation is painless gross hematuria among these young patients, but lower urinary tract symptoms should also be noticed for young patients to rule out tumor. Postoperative tumor recurrence might be associated with multiple lesions, which is not related to the tumor size or pathological features.

[Laparoscopic ureterovesical reimplantation for ureteral stricture after renal transplantation].

OBJECTIVE: To discuss the safety and efficacy of laparoscopic ureterovesical reimplantation in the treatment of transplanted ureteral stenosis. METHODS: One case of laparoscopic ureterovesicalre implantation in the treatment of ureteral stenosis after renal transplantation was reported, and related literatures was reviewed. A 54-year-old woman was admitted to our hospital with main complaint of hydronephrosis of transplanted kidney for five years after renal transplantation. Her physical examination showed slightly bulging in the transplanted kidney area without tenderness. The magnetic resonance urography (MRU) showed that the transplanted kidney and ureter were dilated obviously, with significant dilatation of renal pelvis and calyx, about 5 cm at the widest point of renal pelvis expansion, and the end of ureter was narrow, without abnormal filling defect in the ureter. The primary diagnosis was distal transplanted ureteral stenosis. After twice endoscopic ureteral dilatation by multi-endoscopic technique, there was no improvement in the hydronephrosis after the removal of the stent. After thorough preoperative preparation, laparoscopic ureterovesical reimplantation was performed under general anesthesia. Firstly, the median umbilical ligament, the lateral umbilical ligament and the peritoneal fold were cut off, and the anterior bladder space was dissociated distally. The space of left side wall of the bladder and the pubic bone was gradually dissociated, and the space of anterior bladder wall and the pubic bone was dissociated. Secondly, the right side wall of the bladder was dissociated from the head to the tail, and the surrounding structure was carefully identified to avoid injury of the ureter of the transplanted kidney. The transplanted ureter was sought between the right side of the bladder and the lower pole of the transplanted kidney. The distal end of the ureter was cut open, and the narrow section was cut off, confirming that no stenosis in the proximal ureter. The ureterocystic anastomosis was performed by Lich-Gregoir method (extra-bladder). Finally, the bladder tissue around the anastomosis site was fixed to the right pelvic wall to reduce tension. RESULTS: The operation was completed successfully, the operation time was 210 min, the amount of bleeding was about 30 mL, and there was no surgical complication. The creatinine was stable after operation, with serum creatinine declining to 68 µmol/L, and serum creatinine 94 µmol/L before operation. The patient was discharged 5 days after operation. After follow-up of 3 months, KUB indicated that the position of ureteral stent was good and the function of renal transplantation was stable. CONCLUSION: Laparoscopic ureterovesical reimplantation is a safe and effective treatment for ureteral ureteral stricture after renal transplantation. Compared with open surgery, laparoscopic surgery has less impact on renal renal allograft, with faster recovery, less bleeding, fewer complications, less postoperative pain and minimally invasive wound. This surgical procedure is difficult and requires an experienced urologist with high laparoscopic skills to perform.

[Technical improvement in retroperitoneal laparoscopic living donor nephrectomy: report of 193 cases].

OBJECTIVE: To summarize our experience of retroperitoneal laparoscopic living donor nephrectomy, our continuous technical improvements and refinement of this skill and standardization of each procedure of this operation. METHODS: Having approved by hospital ethical committee and local government administration, a total of 193 living donors underwent retroperitoneal laparoscopic living donor nephrectomy from Dec.2003 to Feb. 2016 in our department. Under general anaesthesia, the operation was performed through 3 lumbar ports. After the kidney was liberated fully and the ureter was severed 7-8 cm under the lower pole of the kidney, the renal artery and vein were blocked with endo-cut or hem-o-lok separately and then severed. Then the kidney was taken out quickly and flushed with 4 °C kidney preserving fluid immediately, the donor kidneys were then preserved in iced saline until kidney transplantation. Clinical data about operation time, volume of blood loss, perioperative complications, renal function of both donors and recipients before and after operation were collected. RESULTS: The 193 retroperitoneal laparoscopic living donor nephrectomy operations were successful with only one operation was converted to open living donor nephrectomy because of hemorrhage and unclear operation field during the operation. The average operation time was 85 min (55-135 min), the average blood loss was 60 mL (20-200 mL), and no donor needed blood transfusion during or after operation. Three donors were found to have hematoma of renal fossa after operation and none of them required further treatment. The average hospital stay after operation was 5.7 days (4-9 days). In the study, 162 donors were followed up for an average of 42 months (1-58 months) and they were all healthy. Two kidney recipients had urinary bladder anastomosis leakage after operation and both needed surgical repair, a new anastomosis of ureter and bladder were made. Three kidney recipients had kidney subcapsular hematoma but required no further treatment. One kidney recipient had delayed graft function and recovered finally and the renal function of other recipients were all normal. Renal function of both donors and recipients during the follow up period were normal. CONCLUSION: Retroperitoneal laparoscopic living donor nephrectomy is a safe and reliable technique, it may become a standardized operation for living kidney transplantation after continuous technical improvement. Precautions must be taken to avoid complications and a skilled hand is necessary for success.

[Radical nephrectomy and thrombectomy for Mayo clinic stage III tumor thrombus: a surgical technique and clinical experience].

OBJECTIVE: To evaluate the effectiveness and safety of radical nephrectomy and inferior vena cava thrombectomy in the treatment of patients with Mayo III tumor thrombus, and to introduce our experience and surgical technique. METHODS: The clinical data of 8 patients with Mayo III tumor thrombus from October 2014 to September 2016 were analyzed retrospectively. Of the 8 patients, 3 were male and 5 were female. The average age was (50.8±18.7) years (18 to 77 years). The average body mass index (BMI) was (22.7±4.4) kg/m2 (15.2 to 30.8 kg/m2). Imaging suggested the right renal tumor in all the 8 cases. The average tumor size was (7.9±2.5) cm. Open radical nephrectomy and inferior vena cava thrombectomy was conducted in 5 cases and laparoscopic surgery in 3 cases, and 1 case was converted to open surgery. RESULTS: All the 8 surgeries were completed successfully with no death case. The average surgery time was (370.3±101.6) min, ranging from 272-567 min. The average vena cava blocked time was (41.0±12.1) min, ranging from 17-55 min. The blood loss volume was (1 181.3±915.7) mL, ranging from 200-3 000 mL. During the operation, 5 cases were infused with suspended red blood cells, the amount of blood transfusion was 800-2 000 mL. 3 cases were infused of plasma with 400-1 000 mL. The average hospital stay was 9-23 d, with an average of (14.1±4.0) d. In the 8 patients, 4 cases underwent inferior vena cava wall resection because of invasion by tumor thrombus. Preoperative serum creatinine was 60-101 µmol/L, with an average of (76.4±15.3) µmol/L. Serum creatinine 1 week after the operation was 74-127 µmol/L, with an average of (100.8±21.1) µmol/L. Pathological diagnosis showed 6 cases of clear cell carcinoma, 1 case of papillary carcinoma type II, and 1 case of Ewing's sarcoma. Among the 8 patients, early postoperative complications occurred in 5 cases. Postoperative complications were graded as level II, according to the Clavien classifications. The 8 cases were followed up for 2 to 24 months with an average of 11.3 months. There was 1 patient who suffered from lung metastasis. CONCLUSION: Our initial clinical results show that radical nephrectomy and inferior vena cava thrombectomy is safe and effective for patients with Mayo III tumor thrombus. The wide extension of grade III vein tumor thrombus leads to the difficulty of operation technique. Sufficient preoperative preparation, rich operative experience and skills can improve the safety of operation.

Interferon-γ affects leukemia cell apoptosis through regulating Fas/FasL signaling pathway.

OBJECTIVE: Imbalance of hematopoietic cell proliferation and apoptosis is one of the major causes of leukemia. Enhanced cell proliferation and reduced apoptosis lead to hemocytes accumulation. Fas/FasL signaling pathway promotes cell apoptosis. This study investigated the impact of interferon γ (IFN-γ) on chronic myelogenous leukemia cell proliferation and apoptosis to elucidate its interaction with Fas/FasL signaling pathway. PATIENTS AND METHODS: Leukemia K562 cells were routinely cultivated and treated with 10 U/ml, 100 U/ml, and 1000 U/ml interferon for 12 h, 24 h, and 48 h, respectively. MTT assay was applied to test cell proliferation. TUNEL assay was adopted to determine cell apoptosis. Western blot was selected to detect Fas/FasL expression. RESULTS: Different concentrations of IFN-γ inhibited cell proliferation at various time points. IFN-γ at 1000 U/ml treatment for 48 h exhibited the strongest suppressive effect on cell proliferation (p < 0.05). IFN-γ intervention enhanced K562 cell apoptosis with concentration and time dependence (p < 0.05). Fas and FasL proteins expressions upregulated after treated by IFN-γ following dose elevation and time extension (p < 0.05). CONCLUSIONS: IFN-γ inhibits leukemia K562 cell proliferation and promotes cell apoptosis via facilitating Fas and FasL proteins expressions.

[Retroperitoneal laparoscopic nephrectomy with autotransplantation for severe iatrogenic ureteral injury].

OBJECTIVE: To evaluate the safety and efficacy of retroperitoneal laparoscopic nephrectomy with autotransplantation in cases of severe iatrogenic proximal ureteral damage. METHODS: From July 2011 to March 2015, two patients, aged 44 (female) and 54 years (male), underwent retroperitoneal laparoscopic nephrectomy and autotransplantation for treatment of severe iatrogenic proximal ureteral injuries. Both injuries were proximal ureteral avulsion during ureterolithotomy with the holmium laser for ureteral calculi. computed tomography angiography (CTA) and computed tomography urography (CTU) was performed in both patients before operation. A 3-port retroperitoneal technique was used for the patients placed in a lateral decubitus position. A retroperitoneal laparoscopic nephrectomy with autotransplantation approach was used in both the patients, and the kidneys were removed to the right iliac fossa. Case 1's kidney was removed through the right Gibson incision, while Case 2's kidney was removed through the left lumbar incision. The renal artery and renal vein were ligated using the Hem-o-lok. The kidneys were taken out quickly from the patients and infused with 4 °C kidney preserving fluid immediately. RESULTS: The retroperitoneal laparoscopic nephrectomy with autotransplantations was performed 4 hours in Case 1 and 2 years in Case 2 after atrogenic proximal ureteral injuries. Case 2 was associated with dense perinephric and perihilar fibrosis. The procedures were successful, with immediate return of renal function in both the patients. After ex vivo graft preparation, ureteral and vessel length and quality were adequate for transplantation in both the cases. A direct ureterovesical anastomosis was performed in both patients. In the 2 patients, the warm ischemia time was 3 and 5 minutes, the total operation time 185 and 246 minutes, and the estimated blood loss 70 and 200 mL, respectively. No perioperative complications occurred. At the end of the follow-up, the transplanted kidneys were functional, and the patients had returned to their normal activity. CONCLUSION: Retroperitoneal laparoscopic nephrectomy with autotransplantation is an excellent alternative to nephrectomyor bowel interposition in patients with proximal ureteral loss. This procedure is associated with acceptable morbidity and preserves the renal function. This report supports the safety and efficacy of retroperotoneal laparoscopic nephrectomy with autotransplantation in experienced hands.

[Retroperitoneal laparoscopic nephrectomy with autotransplantation for severe iatrogenic ureteral injury].

OBJECTIVE: To evaluate the safety and efficacy of retroperitoneal laparoscopic nephrectomy with autotransplantation in cases of severe iatrogenic proximal ureteral damage. METHODS: From July 2011 to March 2015, two patients, aged 44 (female) and 54 years (male), underwent retroperitoneal laparoscopic nephrectomy and autotransplantation for treatment of severe iatrogenic proximal ureteral injuries. Both injuries were proximal ureteral avulsion during ureterolithotomy with the holmium laser for ureteral calculi. computed tomography angiography (CTA) and computed tomography urography (CTU) was performed in both patients before operation. A 3-port retroperitoneal technique was used for the patients placed in a lateral decubitus position. A retroperitoneal laparoscopic nephrectomy with autotransplantation approach was used in both the patients, and the kidneys were removed to the right iliac fossa. Case 1's kidney was removed through the right Gibson incision, while Case 2's kidney was removed through the left lumbar incision. The renal artery and renal vein were ligated using the Hem-o-lok. The kidneys were taken out quickly from the patients and infused with 4 °C kidney preserving fluid immediately. RESULTS: The retroperitoneal laparoscopic nephrectomy with autotransplantations was performed 4 hours in Case 1 and 2 years in Case 2 after atrogenic proximal ureteral injuries. Case 2 was associated with dense perinephric and perihilar fibrosis. The procedures were successful, with immediate return of renal function in both the patients. After ex vivo graft preparation, ureteral and vessel length and quality were adequate for transplantation in both the cases. A direct ureterovesical anastomosis was performed in both patients. In the 2 patients, the warm ischemia time was 3 and 5 minutes, the total operation time 185 and 246 minutes, and the estimated blood loss 70 and 200 mL, respectively. No perioperative complications occurred. At the end of the follow-up, the transplanted kidneys were functional, and the patients had returned to their normal activity. CONCLUSION: Retroperitoneal laparoscopic nephrectomy with autotransplantation is an excellent alternative to nephrectomyor bowel interposition in patients with proximal ureteral loss. This procedure is associated with acceptable morbidity and preserves the renal function. This report supports the safety and efficacy of retroperotoneal laparoscopic nephrectomy with autotransplantation in experienced hands.

Detection of neurotrophin-4 (NT-4) in ejaculated bull spermatozoa and its effect on spermatozoa mitochondrial activity.

Recently, we demonstrated that two members of neurotrophins, nerve growth factor and brain-derived neurotrophic factor, and two types of receptor, tyrosine kinase A (TrkA) and tyrosine kinase (TrkB), exist in ejaculated bull spermatozoa, and play a crucial role in the normal function of spermatozoa. Neurotrophin-4 (NT-4) is another neurotrophic factor that signals predominantly through the TrkB receptor tyrosine kinase, and no reports of detection of NT-4 in spermatozoa have been published. In the present study, the presence of NT-4 in mature bull spermatozoa was investigated using RT-PCR, immunofluorescence and Western blotting. The result shows that there was no RT-PCR evidence for NT-4 transcripts in bovine spermatozoa. However, the NT-4 protein was present in bovine spermatozoa, and the NT-4 immunoreactivity was localized to the equatorial segment and midpiece of bovine spermatozoa. In addition, effects of NT-4 on function of spermatozoa were studied. Significant increased mitochondria activity of mature bovine spermatozoa was observed in response to 300 or 500 ng/ml exogenous NT-4 (p < 0.05), in comparison with the control, while addition of inhibitors (40 ng/ml k252α) specific for tyrosine protein kinase significantly blocked the increase of mitochondria activity. However, NT-4 had no effects on the viability or acrosome reaction of spermatozoa (p > 0.05). Consequently, this study provided evidence that NT-4 protein was presented in the mature bull spermatozoa and can influence the mitochondrial activity of bovine spermatozoa through TrkB tyrosine kinase-dependent pathways.

Progress in cell membrane chromatography.

Cell membrane chromatography (CMC) was first established by He et al. in 1996. A bioaffinity chromatography technique, CMC has since proven to be an important method for studying drug-receptor interactions and screening active compounds from medicinal herbs. This paper briefly reviews the characteristics of the cell membrane stationary phase (CMSP), the CMC analytical system, and its applications.