This study aimed to analyze the clinical features and pathological findings of the largest reported case series of testicular regression syndrome (TRS). Data, including age, affected side, color Doppler ultrasound results, surgical methods, intraoperative conditions, and pathological examinations, of children with unilateral TRS who were treated in our center from December 2012 to November 2021 were retrospectively analyzed. A total of 570 patients were included in this study. The mean age at surgery was 38 (range, 5–193) months. There were 457 cases (80.2%) of left TRS. Preoperative color Doppler ultrasonography found nubbins in 172 cases (30.2%). The long diameter of the contralateral testis was 17.11 (±4.22) mm, and the volume was 0.81 (±1.15) ml. The long diameter was ≥1.6 cm in 62.0% of the patients (240/387) aged ≤3 years. Laparoscopy was performed as the initial surgical step in 513 cases, of which 96.7% of the children had closed internal rings. One or more lesions of fibrosis, hemosiderin, and calcification were found in 92.4% (474/513) of the excised remnants. Germ cells were present in 16 cases (3.1%). In conclusion, TRS is more common on the left side and is usually accompanied by a closed internal ring and compensatory hypertrophy of the contralateral testis. Germ cells are only present in cases where the spermatic vessels enters the internal ring. We recommend that further exploration and excision of the remnants may not be applicable in cases where only the vas deferens has entered the internal ring.

The protective effects of Porphyra yezoensis polysaccharides (PYPs) with molecular weights of 576.2 (PYP1), 105.4 (PYP2), 22.47 (PYP3), and 3.89 kDa (PYP4) on the oxidative damage of human kidney proximal tubular epithelial (HK-2) cells and the differences in adherence and endocytosis of HK-2 cells to calcium oxalate monohydrate crystals before and after protection were investigated. Results showed that PYPs can effectively reduce the oxidative damage of oxalic acid to HK-2 cells. Under the preprotection of PYPs, cell viability increased, cell morphology improved, reactive oxygen species levels decreased, mitochondrial membrane potential increased, S phase cell arrest was inhibited, the cell apoptosis rate decreased, phosphatidylserine exposure reduced, the number of crystals adhered to the cell surface reduced, but the ability of cells to endocytose crystals enhanced. The lower the molecular weight, the better the protective effect of PYP. The results in this article indicated that PYPs can reduce the risk of kidney stone formation by protecting renal epithelial cells from oxidative damage and reducing calcium oxalate crystal adhesion, and PYP4 with the lowest molecular weight may be a potential drug for preventing kidney stone formation.

<b><i>Objective:</i></b> This study aimed to explore the clinical characteristics, treatment methods, and prognosis of neonatal pyocele of tunica vaginalis and to provide a reference for the clinical treatment. <b><i>Methods:</i></b> A total of 56 newborns with pyocele of tunica vaginalis were admitted to our hospital due to the scrotal emergency from January 2015 to January 2020. Our study retrospectively analyzed these 56 cases. Of the 56 cases, including 32 full-term infants and 24 premature infants, age ranged from 1 to 27 days. Initially, conservative treatment (intravenous antibiotic treatment) was applied to 42 cases, and surgery to 14 cases. Then, 7 underwent surgical exploration during the conservative treatment, and 2 cases with initial surgical treatment experienced orchiectomy because of complete necrosis. For 56 cases, the average follow-up time was 18 months. <b><i>Results:</i></b> The clinical recovery time of cases with conservative treatment ranged from 8 to 17 days, with an average of 11.02 ± 2.31 days. The clinical recovery time of cases with surgery ranged from 6 to 15 days, with an average of 9.28 ± 2.78 days. During the follow-up, for 56 cases, except for the 2 cases with orchiectomy, the testicular position and Doppler flow both went back to normal, of the 42 cases with initial conservative treatment, 1 case experienced testicular retardation, of the 14 cases with initial surgical treatment, 2 cases experienced testicular retardation, and hydrocele of 42 cases were self-healed. <b><i>Conclusions:</i></b> Neonatal pyocele of tunica vaginalis is mostly secondary to intra-abdominal infection. Color Doppler ultrasound is helpful for the diagnosis. The percutaneous aspiration is a way of collecting pathogenic bacteria during the conservative treatment. If the color Doppler suggests testicular involvement, surgical exploration should be performed.

Endocytosis is a protective mechanism of renal epithelial cells to eliminate retained crystals. This research investigated the endocytosis of 100 nm calcium oxalate monohydrate crystals in human kidney proximal tubular epithelial (HK-2) cells before and after repair by four kinds of tea polysaccharides with molecular weights (MWs) of 10.88 (TPS0), 8.16 (TPS1), 4.82 (TPS2), and 2.31 kDa (TPS3), respectively. When HK-2 cells were repaired by TPSs after oxalic acid injury, the cell viability, wound healing ability, mitochondrial membrane potential, percentage of cells with endocytosed crystals, and dissolution rate of the endocytosed crystals increased; the cell morphology recovered; and the reactive oxygen level and lactate dehydrogenase release decreased. Most of the endocytosed crystals were found in the lysosomes. The repair effects of the four TPSs were ranked in the following order: TPS2>TPS1>TPS3>TPS0. TPS2 with moderate MW presented the optimal repair ability and strongest ability to promote endocytosis.