Sex differences in fetal brain functional network topology.

The fetal period is a critical stage in brain development, and understanding the characteristics of the fetal brain is crucial. Although some studies have explored aspects of fetal brain functional networks, few have specifically focused on sex differences in brain network characteristics. We adopted the graph theory method to calculate brain network functional connectivity and topology properties (including global and nodal properties), and further compared the differences in these parameters between male and female fetuses. We found that male fetuses showed an increased clustering coefficient and local efficiency than female fetuses, but no significant group differences concerning other graph parameters and the functional connectivity matrix. Our study suggests the existence of sex-related distinctions in the topological properties of the brain network at the fetal stage of development and demonstrates an increase in brain network separation in male fetuses compared with female fetuses.

Endometrial carcinoma: use of tracer kinetic modeling of dynamic contrast-enhanced MRI for preoperative risk assessment.

BACKGROUND: To compare two tracer kinetic models in predicting of preoperative risk types in endometrial carcinoma (EC) using DCE-MRI. METHODS: A prospective study of patients with EC was conducted with institutional ethics approval and written informed consent. DCE-MRI data was analyzed using the extended Tofts (ET) and the distributed parameter (DP) models. DCE parameters blood flow (F), mean transit time, blood volume (Vp), extravascular extracellular volume (Ve), permeability surface area product (PS), extraction fraction, transfer constant (Ktrans), and efflux rate (Kep) between high- and low-risk EC were compared using the Mann-Whitney test. Bland-Altman analysis was utilized to compare parameter consistency and Spearman test to assess parameter correlation. Diagnostic performance of DCE parameters was analyzed by receiver-operating characteristic curve and compared with traditional MRI assessment. RESULTS: Fifty-one patients comprised the study group. Patients with high-risk EC exhibited significantly lower Ktrans, Kep, F, Vp and PS (P < 0.001). ET-derived Ktrans and DP-derived F attained AUC of 0.92 and 0.91, respectively. Bland-Altman analysis showed that the consistency of Ve or Vp between the two models was low (P < 0.001) while Spearman test showed a strong correlation (r = 0.719, 0.871). Both Ktrans and F showed higher accuracy in predicting EC risk types than traditional MRI assessment. CONCLUSIONS: Kinetic parameters derived from DCE-MRI revealed a more hypovascular microenvironment for high risk EC than to low- risk ones, providing potential imaging biomarkers in preoperative risk assessment that might improve individualized surgical planning and management of EC.

[Comparison among three standards of TW2 to skeletal age determination in children with central precocious puberty].

OBJECTIVE: To discuss the diagnostic value of English, Chinese and Japanese standards of TW2 to skeletal age assessment of children with central precocious puberty (CPP), then to confirm the normal thresholds. METHODS: Sixty one children as patient group were definitely assured CPP. The control group had 67 children. Among them, 61 were normal children, another 6 children as a special control group. Left hand-wrist X-ray radiographs were retrospectively analyzed by two doctors separately and their skeletal ages were assessed with the three standards of TW2 method. The differences between skeletal age and chronological age were analyzed with ROC in SPSS 13.0. RESULTS: (1) The skeletal age results showed kappa value is 0.776 deduced by two clinical doctors(u = 16.128, P < 0.05). (2) There were no statistic differences for the areas under ROC curves among three methods. (3) d > or = 1.15 years in TW2, d > or = 1.25 years in TW2-CHN and d > or = 0.65 years in TW2-JP were more susceptive and specific points. CONCLUSION: TW2, TW2-CHN and TW2-JP provided a higher value for the diagnosis of skeletal age in unhealthy children, and TW2-CHN is highest value for Chinese children.