Maternal uniparental disomy for chromosome 6 in 2 prenatal cases with IUGR: case report and literature review.

BACKGROUND: Uniparental disomy (UPD) is a rare genetic condition leading to potential disease risks. Maternal UPD of chromosome 6 upd(6)mat is exceptionally rare, with limited cases reported. This study reported two new cases of upd(6)mat and reviewed the literature of previous cases. CASE PRESENTATION: Both cases exhibited intrauterine growth restriction (IUGR), and genetic analysis confirmed upd(6)mat in each case. The literature review identified a total of 19 cases. IUGR and preterm labor were the most common two symptoms observed, and additional anomalies and genetic variations were also reported in some cases. CONCLUSION: upd(6)mat is potentially associatied with IUGR, but the precise genotype-phenotype relationship remains unclear. The cases with upd(6)mat may present clinical features due to imprinting disorders.

Whole-exome sequencing increases the diagnostic rate for prenatal fetal structural anomalies.

BACKGROUND: Prenatal whole-exome sequencing (WES) is becoming increasingly used when karyotype and microarray tests are not diagnostic of fetal malformations. Although the value of WES clearly emerges in terms of higher diagnostic rates, the limitations of prenatal phenotyping together with the counseling challenges for variants of uncertain significance and incidental results suggest that the routine application of prenatal WES is not yet easy. METHODS: Structurally abnormal fetuses with a mean gestational age of 24 weeks (range 13-38 weeks) were recruited from the Chong Qing Health Center for Women and Children. We performed a retrospective WES investigation in 85 fetuses, using DNA from amniotic fluid (66 samples, 77.6%), umbilical cord blood (10 samples, 11.8%), and fetal tissues (9 samples, 10.6%). Parental DNA was extracted from peripheral blood. RESULTS: Molecular diagnosis was obtained in 16 of the 85 fetuses (18.8%). According to the variant segregation mode and family history, 7 fetuses (43.75%) were affected by an autosomal dominant condition (6 variants were de novo and 1 variant was inherited from an unknowingly affected father), 7 fetuses (43.75%) had an autosomal recessive syndrome always associated with compound heterozygosity, and 2 fetuses (12.5%) had an X-linked condition (one mother was a carrier). In addition, the highest diagnostic rate was observed in fetuses with multisystem abnormalities (38.9%, 7/18). A variant of uncertain significance was detected in 16 samples (18.8%, 16/85). CONCLUSION: Our study confirms that prenatal WES is an efficient tool for studying fetal abnormalities, although further improvements are needed to establish stronger fetal genotype-phenotype correlations.

Individualized risk prediction of significant fibrosis in non-alcoholic fatty liver disease using a novel nomogram.

Background: Fibrosis is deemed to be a pivotal determinant of the long-term prognosis in non-alcoholic fatty liver disease (NAFLD). Objective: We aimed to develop a novel nomogram-based non-invasive model to accurately predict significant fibrosis in patients with NAFLD. Methods: We designed a prospective cohort study including 207 patients with biopsy-proven NAFLD. Detailed anthropometric and fibrosis-related laboratory parameters were collected. A nomogram was established based on variables that were independently associated with significant fibrosis identified by the logistic regression model. Then it was compared with aspartate aminotransferase-to-platelet ratio index (APRI), NAFLD fibrosis score (NFS), FIB-4 and BARD score. Diagnostic accuracy was assessed according to area under the receiver operator characteristic curve (AUROC), sensitivity, specificity, positive and negative predictive values, and decision curve analysis. Results: Variables included in the nomogram were: waist-to-height ratio, hyaluronic acid, procollagen-III-peptide, chitinase-3-like protein 1, and cytokeratine-18 neoepitope M65. The discrimination ability of the nomogram (AUROC = 0.829, 95%CI 0.755-0.904) was significantly superior to APRI (AUROC = 0.670, 95%CI 0.563-0.777), NFS (AUROC = 0.601, 95%CI 0.480-0.722), FIB-4 (AUROC = 0.624, 95%CI 0.511-0.736) and BARD (AUROC = 0.579, 95%CI 0.459-0.699) for significant fibrosis (all p < 0.05). The nomogram showed a larger net benefit to aid in decision-making as to whether biopsy is required. Conclusions: This novel nomogram was more accurate, and achieved higher net benefit than APRI, NFS, FIB-4 and BARD to detect significant fibrosis. It can be useful as a non-invasive method to screen ≥F2 fibrosis in the overall population with NAFLD.

Lifestyle interventions for patients with nonalcoholic fatty liver disease: a network meta-analysis.

Lifestyle interventions remain the first-line therapy for nonalcoholic fatty liver disease (NAFLD). This study aims to evaluate the individual impact of exercise and/or dietary interventions on the level of alanine aminotransferase (ALT), aspartate aminotransferase (AST), homeostasis model of assessment for insulin resistance index (HOMA-IR), and BMI. Randomized-controlled trials from patients diagnosed with NAFLD were included in the meta-analysis if they reported the associations between changes in ALT, AST, HOMA-IR, or BMI and types of lifestyle interventions. Nineteen eligible articles were included. Compared with observation, aerobic exercise training (AEx) plus diet [weighted mean difference (WMD)=-25.85; 95% confidence interval (CI): -43.90 to -7.80], AEx (WMD=-8.81; 95% CI: -20.22-2.60) and diet (WMD=-11.85; 95% CI: -47.65-24.95) showed significant efficacy in the improvement of ALT levels. Also AST, AEx plus diet showed a significant tendency to reduce AST levels. In addition, progressive resistance training (WMD=-1.70; 95% CI: -5.61-2.21) led to the most obvious reduction in HOMA-IR compared with observation, but appeared to show no significant effect in BMI (WMD=0.27; 95% CI: -0.48 to -0.07), whereas AEx plus diet (WMD=-0.96; 95% CI: -1.54 to -0.38 and WMD=-1.96; 95% CI: -2.79 to -1.12) showed great efficacy both in the improvement of HOMA-IR and BMI. AEx plus diet is the most effective intervention in the management of patients with NAFLD. Dietary intervention may be more effective in the improvements of aminotransferases, whereas exercise shows superiority in improving insulin sensitivity and reduction of BMI.