[Clinical features and genetic analysis of two children with Williams-Beuren syndrome].

OBJECTIVE: To explore the clinical and genetic characteristics of two children with Williams-Beuren syndrome (WBS). METHODS: Two children who had presented at the Department of Pediatrics, General Hospital of Ningxia Medical University respectively on January 26 and March 18, 2021 were selected as the study subjects. Clinical data and results of genetic testing of the two patients were analyzed. RESULTS: Both children had featured developmental delay, characteristic facies and cardiovascular malformation. Child 1 also had subclinical hypothyroidism, whilst child 2 had occurrence of epilepsy. Genetic testing revealed that child 1 has harbored a 1.54 Mb deletion in the 7q11.23 region, whilst child 2 has a 1.53 Mb deletion in the same region, in addition with a c.158G>A variant of the ATP1A1 gene and a c.12181A>G variant of the KMT2C gene. Based on the guidelines from the American College of Medical Genetics and Genomics, the c.158G>A and c.12181A>G variants were rated as variants of unknown significance (PM1+PM2_Supporting+PP2+PP3；PM2_Supporting). CONCLUSION: Both children had characteristic features of WBS, for which deletions of the 7q11.23 region may be accountable. For children manifesting developmental delay, facial dysmorphism and cardiovascular malformations, the diagnosis of WBS should be suspected, and genetic testing should be recommended to confirm the diagnosis.

Rhinitis symptom in patients with self-reported allergic rhinitis is influenced by sensitization pattern: A cross-sectional study of China.

BACKGROUND: Allergic rhinitis (AR) is characterized by distinct clinical heterogeneity and allergic sensitization patterns. We aimed to quantify rhinitis symptoms in patients with self-reported allergic rhinitis according to the potential sensitization patterns for relevant allergens in China. METHODS: We used latent class analysis (LCA; a subset of structural equation modeling) to independently cluster patients into different patterns of atopic sensitization in an unsupervised manner, based on specific immunoglobulin E tests. AR symptom severity was assessed by the visual analogue scale. We evaluated the association between the severity of AR and the allergen sensitization patterns. RESULTS: LCA revealed four phenotypes of atopic sensitization among 967 patients with self-report AR. We labeled latent classes as: Class 1, weed pollens and indoor sensitization (n = 74 [7.7%]); Class 2, weed pollen with low indoor sensitization (n = 275 [28.4%]); Class 3, low or no sensitization (n = 350 [36.2%]); and Class 4, house dust mite-dominated sensitization (n = 268 [27.7%]). AR was more severe in Class 2 compared to the other 3 classes, indicating that upper respiratory symptoms are more severe among patients with isolated seasonal rhinitis. CONCLUSION: We have identified four sensitization patterns in patients with self-reported AR, which were associated with different clinical symptoms and comorbidities.

Hysteresis Compensation for a Piezoelectric Actuator of Active Helicopter Rotor Using Compound Control.

Active rotor with trailing-edge flaps is a promising method to alleviate vibrations and noise level of helicopters. Hysteresis of the piezoelectric actuators used to drive the flaps can degrade the performance of an active rotor. In this study, bench-top tests are conducted to measure the nonlinear hysteresis of a double-acting piezoelectric actuator. Based on the experimental data, a rate-dependent hysteresis model is established by combining a Bouc-Wen model and a transfer function of a second order system. Good agreement is exhibited between the model outputs and the measured results for different frequencies. A compound control regime composed of a feedforward compensator and PID (Proportional-Integral-Derivative) feedback control is developed to suppress the hysteresis of this actuator. Bench-top test results demonstrate that this compound control regime is capable to suppress hysteresis at different frequencies from 10 Hz to 60 Hz, and errors between the desired actuator outputs and the measured outputs are reduced dramatically at different frequencies, revealing that this compound control regime has the potential to be implemented in an active helicopter rotor to suppress actuator hysteresis.

A 10-year retrospective comparative analysis of the clinical features of brucellosis in children and adults.

INTRODUCTION: Brucellosis is a zoonosis with a wide spectrum of clinical manifestations. However, it is still unclear whether the clinical manifestations in children are significantly different from those in adults. METHODOLOGY: Patients with brucellosis and treated at the General Hospital of Ningxia Medical University between 2009 and 2019 were divided into two groups; children (88) and adults (354). Thereafter, the records of the two groups were analyzed retrospectively. RESULTS: The findings showed that: 1. School-age children, young and middle-aged individuals were more likely to suffer from brucellosis and most were male; 2. Fever and arthralgia were the most common manifestations in the two groups. In addition, fatigue and low back pain were rare in children although fever and lymphadenopathy were more common in this group. However, hepatomegaly and splenomegaly were common in both groups; 3. The most common complication was osteoarthritis and peripheral arthritis occurred more frequently in children. On the other hand, spondylitis was the most common in adults (this particularly involved the lumbar and sacral vertebrae); 4. An increase in the erythrocyte sedimentation rate, levels of the C-reactive protein and liver enzymes was common in both two groups; 5. There was no significant difference in the positive rate of the standard agglutination test between children (96.59%) and adults (95.20%). However, the positive rate of blood culture was higher in children (65.85%) than in adults (51.00%). CONCLUSIONS: Brucellosis causes damage to multiple systems and differences in clinical characteristics were found between children and adults.