The prevalence and clinical presentation of Hirschsprung's disease in preterm infants: a systematic review and meta-analysis.

PURPOSE: Hirschsprung's disease (HD) is a rare occurrence in premature infants, and the exact prevalence varying across studies. Thus, we conducted this study to determine the prevalence of and clinical presentation of HD in preterm infants. METHODS: The PubMed, EmBase, and Cochrane library databases were searched for eligible studies throughout May 2021. The pooled incidence with 95% confidence interval (CI) was calculated using the random-effects model. RESULTS: Thirty studies involved 4,557 children with HD were included. The pooled proportion of HD patients who were preterm infants was 7% (95% CI 5-8%; P < 0.001); the sensitivity analysis indicated that the pooled prevalence of preterm infants with HD ranged from 5.0% to 5.6%. Moreover, the pooled incidence of abdominal distention in HD patients was 83% (P < 0.001), that of vomiting was 61% (P < 0.001), that of bilious vomiting was 54% (P < 0.001), that of delayed meconium passage was 48% (P < 0.001), that of constipation was 44% (P < 0.001), and that of enterocolitis was 13% (P < 0.001). CONCLUSIONS: This study reported the prevalence of HD patients who were preterm infants, and the most common presentations were abdominal distention, vomiting, bilious vomiting, delayed meconium passage, constipation, and enterocolitis.

Circulating exosomal microRNA-18a-5p accentuates intestinal inflammation in Hirschsprung-associated enterocolitis by targeting RORA.

The relevance of stem cell-derived exosomes has been implicated in necrotizing enterocolitis, while the involvement of serum-derived exosomes from children with Hirschsprung-associated enterocolitis (HAEC) in pathogenesis of HAEC remains unclear. This study set to identify the roles of exosomal microRNA (miR)-18a-5p from sera of HAEC patients in human-derived colonic epithelial NCM460 cells and in mice with HAEC. Exosomes were isolated from the sera of healthy children (Healthy-exo), patients with Hirschsprung's disease (HSCR) (HSCR-exo) or HAEC (HAEC-exo). A microarray analysis of miRNAs was implemented to assess the enrichment of miRNAs in these exosomes. HAEC-exo was significantly enriched in miR-18a-5p. HAEC-exo led to the generation of a pro-inflammatory microenvironment, inhibition of cellular DNA synthesis, and promotion of apoptosis in NCM460 cells. Mechanistically, miR-18a-5p targeted and repressed retinoid-related orphan receptor α (RORA) expression, thereby regulating the Sirtuin 1 (SIRT1)/nuclear factor-kappa B (NFκB) pathway. Overexpression of RORA ameliorated inflammatory damage in NCM460 cells caused by exosomal miR-18a-5p. HAEC-exo exacerbated inflammatory damage in HAEC mice, and this facilitation was reversed after RORA overexpression. Collectively, exosomal miR-18a-5p was a promoter of HAEC, which induces the intestine cell apoptosis and inflammatory responses through the inhibition of SIRT1/NFκB pathway by targeting RORA.

Testis-sparing surgery in children with testicular tumors: A systematic review and meta-analysis.

Testis-sparing surgery (TSS) has been increasingly used for treating a variety of testicular tumors (TTs) in children. However, the indications and feasibility associated with TSS remain uncertain. This study aimed to present the clinical outcomes of TSS in children with TTs. The PubMed, Cochrane Library, and Embase databases were reviewed for relevant articles on the clinical outcomes of TSS in children. Recurrence rate, benign rate, rate of TSS and its 95% confidence interval (CI) were calculated. A total of nine relevant studies with 320 patients were included in this study. The recurrence rate was 5.8% (95% CI: 2.3%-14.1%), benign rate was 70.9% (95% CI: 56.3%-82.1%), the rate of TSS (RTSS) was 36.2% (95% CI: 26.1%-47.8%), RTSS in benign tumor was 48.4% (95% CI: 34.3%-62.9%) and rate of elevated AFP was 29.3% (95% CI: 19.7%-41.3%) in children with TTs. Regarding the distribution of TTs, 159 (49.6%) were teratomas, 74 (23.1%) were yolk sac tumors, 36 (11.3%) were epidermoid cysts, 3 (0.9%) were rhabdomyosarcomas, 7 (2.2%) were leydig cell tumor, 6 (1.8%) were sex-cord stromal tumor, 8(2.5%) were mixed malignant germ cell tumors, 3(0.9%) were hemangioma, and 4(1.3%) were adrenal rest tumors. The findings of this meta-analysis suggested that most of the TTs in children were benign, and the most common histologic subtype was teratoma. TSS should be provided to children with benign lesions. This study confirmed that very low rates of tumor recurrence were observed in children with TTs.

Tunable multiwavelength fiber laser based on a double Sagnac HiBi fiber loop.

A tunable multiwavelength fiber laser based on double Sagnac loops is proposed and demonstrated. Comb filter characteristics of single and double Sagnac loops are analyzed by Jones matrix. Simulated results show that there are better tunability and controllability with double loops than with a single loop, and this also has been confirmed by experimental results. By adjusting the polarization controller and the length of the polarization maintaining fiber the wavelength range, wavelength spacing, and laser linewidth can be tuned. Experimental results indicate that the linewidth of the multiwavelength fiber laser was 0.0187 nm and the optical sidemode suppression ratio was 50 dB.