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Objective To describe 19 years of clinical experience managing pediatric patients with testicular yolk sac tumors at the Chongqing Medical University Affiliated Children's Hospital. Methods This study involved a retrospective review of the records of 61 pediatric patients who presented with testicular yolk sac tumor at our institution between 1995 and 2014. Results All patients presented with a painless scrotal mass. Serum alpha-fetoprotein (AFP) levels were elevated (n = 15). Ultrasonography identified the yolk sac tumors as solid masses. Color Doppler flow imaging showed rich blood flow inside and around the masses in 84.8% cases. X-ray of the scrotum showed no intrascrotal calcification (n = 38). Inguinal orchiectomy was performed in 60 patients, one case was treated with testis-sparing surgery. In 11 cases, radical dissection of the inguinal lymph nodes was performed. Histological analysis showed pathologies typical of yolk sac tumor including microcapsule and reticular structures, gland tube-gland bubble structures, an embryo sinus structure, and papillary structures. All patients received postoperative chemotherapy. Serum AFP levels returned to normal 1 to 2 months after surgery. No patients treated with surgery in our hospital relapsed. Conclusion Testicular yolk sac tumor presents as a painless scrotal mass, increased serum AFP levels, and a solid mass on ultrasound. Chest radiography and abdominal ultrasound should be used to accurately stage the tumor. We advocate for inguinal orchiectomy for Stage I disease and postoperative chemotherapy to prevent recurrence in the ipsilateral or contralateral testis. [ABSTRACT FROM AUTHOR]

The STECE satellite is a small satellite mission of China for space technology experiment and climate exploration. To test the in-flight performance of the CMOS Active Pixel Sensor (APS) based star trackers, the APS-01 star tracker has been loaded on the STECE satellite. The APS-01 star tracker payload delivers 1Hz real time telemetry attitude data during its in-orbit experiment mission. These attitude data have been analyzed and evaluated down to the specification requirements like random noise, systematic bias and low frequency error in this paper. The systematic bias of APS-01, including precession-nutation, aberration and relative installation error, has been calibrated. An approach is proposed to analyze the attitude low frequency errors of APS-01. The results of the evaluation can contribute to a better understanding as well as further refinements of the CMOS APS based star trackers. [ABSTRACT FROM AUTHOR]

A parameter estimation method is presented by an example of an electrohydraulic position servo. The method is based on the Markov chain Monte Carlo approach. The method allows utilization of noisy measurement data in identification process, making use of original physical data possible without the requirement of a filter. The method seeks for the best fitting point estimate of the unknown model parameter vector, but the solution to the parameter estimation problem is given as a statistical distribution that contains "all" the possible parameter combinations. The robustness of the model developed with the proposed method is further demonstrated by verification in operat-ing conditions that are independent of each other and the one used in the identifica-tion step. Results show that the system model with the hybrid leakage formula for the studied valve describes the system dynamics more precisely and matches the real responses better. [ABSTRACT FROM AUTHOR]

Background and PurposeThis study investigated the safety and efficacy of using the minimally invasive operation of laparoscopic orchiopexy to treat palpable inguinal canalicular undescended testes.Patients and MethodsLaparoscopic orchiopexy was performed on 90 Chinese patients (103 testes) with inguinal canalicular palpable undescended testes. Patients with testes that were nonpalpable, ectopic, retractable, or palpable but distal to the external ring were excluded. Patients in the study ranged from 8 months to 6 years old (mean age 17 months). Of the 103 testes undergoing operation, 26.7 were on the left side of the body and 58.9 were on the right; 14.4 of the patients had bilateral undescended testes. Laparoscopic techniques were used by the same surgeon to move the spermatic vessels and transfer the testis into the scrotum.ResultsAll 103 testes were successfully descended by laparoscopy. In the first 46 unilateral cases, the operation took significantly longer for the first 15 patients than the next 31, which were completed in 32.7 ± 5.2 min. Of all 90 patients, a complication was encountered in only one, and this occurred at the beginning of the surgeon's learning curve. Of 77 unilateral undescended testes, a patent processes vaginalis was found in 90.3 of the cases on the ipsilateral side and 15.6 on the contralateral side. All of the testes maintained an adequate size and intrascrotal position with no atrophy or recurrent inguinal hernia during a follow-up of 6 to 12 months.ConclusionsThe laparoscopic approach to orchiopexy is a safe way to descend the inguinal canalicular palpable testis. It offers several advantages of a minimally invasive technique and yield effective results. [ABSTRACT FROM AUTHOR]

The extracellular portion (amino acids 95–281 or 114–281) of the human tumor necrosis factor-related apoptosis-inducing ligand (sTRAIL) was genetically linked to the C terminus of the fluoresce-enhanced green fluorescent protein variant (EGFP) to generate two versions of EGFP–sTRAIL fusion proteins, designated EGFP–sTR95 and EGFP–sTR114, respectively. The two versions of EGFP–sTRAIL fusion proteins both induce extensive apoptosis in lymphoid as well as nonlymphoid tumor cell lines. In addition, the two versions of fusion proteins retain similar fluorescence spectra to those of EGFP and have shown the specific binding to TRAIL receptor-positive cells; thus, the stained cells could be analyzed with flow cytometry. Hence, the two versions of fusion proteins represent a readily obtainable source of biologically active sTRAIL that may prove useful in exploit fully the characteristics of both the soluble TRAIL and its receptor system. [ABSTRACT FROM AUTHOR]

Soybean hull peroxidase (SHP) was crystallised from an enzyme solution with low purity by a simple method. The enzyme solution was purified by cooperation salting out of acetone and ammonium sulphate, and lumpy crystals were obtained with the size of about 40 × 30 μm when ammonium sulphate was quickly added to the enzyme solution. The crystal was examined and confirmed to be an SHP crystal by the method of activity test. The result shows that, though the purity of the enzyme solution was not high, crystals could be formed when the enzyme solution rapidly reached to a degree of supersaturation, which was different from the traditional methods of protein crystallisation. Additionally, a purification method of acetone and ammonium sulphate fractional salting out was also studied, in which the procedure was simplified, and a satisfactory purification effect was obtained. [ABSTRACT FROM AUTHOR]