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In massive MIMO systems, due to inversion of Hermitian matrix, the complexity of the traditional ZF precoding method increases exponentially with increase of the number of users. To solve this problem, a low complexity digital ZF precoding scheme based on weighted Gauss-Seidel (WGS) was proposed. That was weighted addtion the iteration results of previous step and Gausee-Seidel iteration results to accelerate the iterative convergence. The weighting factor was determined by the least mean square sum, and the weighting factor was proved to make the algorithm converge. The simulation results show that the WGS algorithm can approximate the performance of ZF precoding scheme with very few iterations, and reduce the complexity of ZF precoding from O(K¹) to O(K²), where K is the number of users. [ABSTRACT FROM AUTHOR]

A 2-year-old boy was admitted to Shanghai Children's Medical Center, Shanghai Jiao Tong University School of Medicine in Nov 30 th , 2018, due to polydipsia, polyphagia, polyuria accompanied with increased glucose levels for more than 2 weeks. He presented with symmetrical short stature [height 81 cm (－2.2 SD), weight 9.8 kg (－2.1 SD), body mass index 14.94 kg/m 2 ( P 10 - P 15 )], and with no special facial or physical features. Laboratory results showed that the glycated hemoglobin A1c was 14%, the fasting C-peptide was 0.3 ng/mL, and the islet autoantibodies were all negative. Oral glucose tolerance test showed significant increases in both fasting and postprandial glucose, but partial islet functions remained (post-load C-peptide increased 1.43 times compared to baseline). A heterozygous variant c.1366C>T (p.R456C) was detected in GATA6 gene, thereby the boy was diagnosed with a specific type of diabetes mellitus. The boy had congenital heart disease and suffered from transient hyperosmolar hyperglycemia after a patent ductus arteriosus surgery at 11 months of age. Insulin replacement therapy was prescribed, but without regular follow-up thereafter. The latest follow-up was about 3.5 years after the diagnosis of diabetes when the child was 5 years and 11 months old, with the fasting blood glucose of 6.0-10.0 mmol/L, and the 2 h postprandial glucose of 17.0-20.0 mmol/L.

Objectives: To analyze the clinical and genetic characteristics of children with autosomal dominant neurodevelopmental disorders caused by kinesin family member 1A (KIF1A) gene variation., Methods: Clinical and genetic testing data of 6 children with KIF1A gene de novo heterozygous variation diagnosed in Shanghai Children's Medical Center Affiliated to Shanghai Jiao Tong University School of Medicine from the year 2018 to 2020 were retrospectively analyzed. Pathogenic variants were identified based on whole exome sequencing, and verified by Sanger sequencing. Moreover, the effect of variants on three-dimensional structure and stability of protein was analyzed by bioinformatics., Results: Among 6 patients there were 4 males and 2 females, and the age of consultation varied from 7 months to 18 years. All cases had varying degrees of motor developmental delay since childhood, and 4 of them had gait abnormalities or fell easily. In addition, 2 children were accompanied by delayed mental development, epilepsy and abnormal eye development. Genetic tests showed that all 6 cases had heterozygous de novo variations of KIF1A gene, including 4 missense mutations c.296C>T (p.T99M), c.761G>A (p.R254Q), c.326G>T (p.G109V), c.745C>G (p.L249V) and one splicing mutation c.798+1G>A, among which the last three variants have not been previously reported. Bioinformatics analysis showed that G109V and L249V may impair their interaction with the neighboring amino acid residues, thereby impacting protein function and reducing protein stability, and were assessed as "likely pathogenic". Meanwhile, c.798+1G>A may damage an alpha helix in the motor domain of the KIF1A protein, and was assessed as "likely pathogenic"., Conclusions: KIF1A -associated neurological diseases are clinically heterogeneous, with motor developmental delay and abnormal gait often being the most common clinical features. The clinical symptoms in T99M carriers are more severe, while those in R254Q carriers are relatively mild.

Objective: To explore the clinical characteristics and genetic basis of a child with Teebi hypertelorism syndrome 1 (TBHS1)., Methods: A child with TBHS1 who was admitted to the Children's Medical Center Affiliated to Shanghai Jiao Tong University School of Medicine on July 13, 2021 was selected as the study subject. Clinical data of the child was collected. Peripheral blood samples of the child and his parents were collected and subjected to whole exome sequencing (WES). Candidate variant was verified by Sanger sequencing and bioinformatic analysis., Results: The child, a 13-year-old male, had manifested delayed growth and development. WES results revealed that he has harbored a heterozygous c.1244A>G variant of the SPECC1L gene, which was verified to be de novo in origin. The variant has not been included in the HGMD and gnomAD databases. As predicted by online software including PolyPhen-2, SIFT, and Mutation Taster, the variant may affect the function of protein domain. And PyMOL software has predicted that the structural stability of SPECC1L protein (p.Gln415Arg) might be reduced. Based on the guidelines of the American College of Medical Genetics and Genomics (ACMG), the variant was classified as pathogenic (PM6+PM1+PP4+PM2_Supporting+PP3)., Conclusion: The heterozygous c.1244A>G variant of the SPECC1L gene probably underlay the TBHS1 in this child. Above finding has expanded the genotypic and phenotypic spectrum of the SPECC1L gene and provided a basis for the clinical diagnosis of this child.

Objective: To investigate the clinical and genetic characteristics of a patient with STISS syndrome due to variant of PSMD12 gene., Methods: Clinical data and result of genetic testing of a patient who was admitted to Shanghai Children's Medical Center, Shanghai Jiaotong University School of Medicine on October 4, 2020 were analyzed, together with a review of relevant literature., Results: The patient was found to harbor a heterozygous c.601C>T (p.Arg201*) nonsense variant of the PSMD12 gene, which was unreported previously. Clinically, the height of the patient has differed significantly from reported in the literature. An extremely rare case of STISS syndrome due to variant of the PSMD12 gene has been diagnosed., Conclusion: Whether the severely short stature is part of the clinical spectrum for PSMD12 gene variants needs to be further explored, and the efficacy and safety of growth hormone therapy has yet to be determined.

Objective: To explore the clinical and genetic characteristics of a child with frontometaphyseal dysplasia 1 (FMD1) due to variant of FLNA gene., Methods: Clinical phenotype of the patient was analyzed. Whole exome sequencing (WES) was carried out to detect pathogenic genetic variants. Sanger sequencing was used to verify the result in his parents., Results: The 2-year-and-9-month-old boy presented with facial dysmorphism (supraorbital hyperostosis, down-slanting palpebral fissure and ocular hypertelorism), skeletal deformities (bowed lower limbs, right genu valgum, left genu varus, slight deformity of index and middle fingers, and flexion contracture of little fingers). He also had limited left elbow movement. High-throughput sequencing revealed that he has carried a de novo heterogeneous c.3527G>A (p.Gly1176Glu) missense variant of the FLNA gene. The same variant was found in neither parent., Conclusion: The clinical manifestations of FMD1 such as joint contracture and bone dysplasia can occur in infancy and deteriorate with age, and require long-term follow-up and treatment. Above finding has expanded the spectrum of FLNA gene variants.

Objective: To explore the genetic basis for 7 patients with Alström syndrome., Methods: DNA was extracted from peripheral blood samples of the patients and their parents. Whole exome sequencing was carried out for the patients. Suspected variant was verified by Sanger sequencing and bioinformatic analysis., Results: Genetic testing revealed 12 variants of the ALMS1 gene among the 7 patients, including 7 nonsense and 5 frameshift variants, which included c.5418delC (p.Tyr1807Thrfs*23), c.10549C>T (p.Gln3517*), c.9145dupC (p.Thr3049Asnfs*12), c.10819C>T (p.Arg3607*), c.5701_5704delGAGA (p.Glu1901Argfs*18), c.9154_9155delCT (p.Cys3053Serfs*9), c.9460delG (p.Val3154*), c.9379C>T (p.Gln3127*), c.12115C>T (p.Gln4039*), c.1468dupA (p.Thr490Asnfs*15), c.10825C>T (p.Arg3609*) and c.3902C>A (p.Ser1301*). Among these, c.9154_ 9155delCT, c.9460delG, c.9379C>T, and c.1468dupA were unreported previously. Based on the standards and guidelines of American College of Medical Genetics and Genomics, the c.9379C>T and c.12115C>T variants of the ALMS1 gene were predicted to be likely pathogenic (PVS1+PM2), whilst the other 10 variants were predicted to be pathogenic (PVS1+ PM2+ PP3+PP4)., Conclusion: ALMS1 variants probably underlay the Alström syndrome in the 7 patients, and genetic testing can provide a basis for the clinical diagnosis of this syndrome. The discovery of four novel variants has expanded the mutational spectrum of Alström syndrome.

Objective: To analyze the clinical characteristics and genetic variation in a child with acrodysostosis type 2., Methods: The child has undergone history taking and physical examination. Genome DNA was extracted from peripheral blood samples from him and his parents. High-throughput sequencing was carried out. The result was verified by Sanger sequencing., Results: The 8-year-old boy presented with midface hypoplasia, hypertelorism, prominent nasal bridge, small and upturned nostrils, broad thumb and great toes, and brachydactyly of remaining fingers and toes. Genetic testing revealed that the child has carried a heterozygous c.1813T>C (p.Tyr605His) missense mutation of the PDE4D gene. The same mutation was not found in either parent and was unreported previously., Conclusion: The child was diagnosed with acrodysostosis type 2 due to the novel mutation of the PDE4D gene.

Objective: To explore the clinical characteristics and genetic basis for an infant featuring combined pituitary hormone deficiency., Methods: Clinical data and results of DNA sequencing of the child were analyzed., Results: The 10-month-old male infant presented with recurrent hypoglycemia, extremely poor appetite and constipation, and severe growth retardation from 2 months on, in addition with pituitary hormone deficiency involving growth hormone, thyroid stimulating hormone, and prolactin. Next generation sequencing revealed a novel heterozygous c.767-769del (p.Glu256del) variant of the POU1F1 gene in the patient., Conclusion: The patient was diagnosed with combined pituitary hormone deficiency due to the POU1F1 gene variant, for which replacement therapy including thyroxine and growth hormone was provided. Hypoglycemia is unusual in patients carrying POU1F1 gene variants and requires close attention in clinical practice. For children with multiple pituitary hormone deficiency, genetic testing should be recommended to determine the cause.

Noonan syndrome is a common genetic disease characterized by peculiar face, short stature, congenital heart disease and thoracic deformity. The pathogenesis of Noonan syndrome is mainly related to abnormal Ras-MAPK signal pathway which involves more than 16 genes including (PTPN11, SOS1, RAF1)] and KRAS. At present, there is a lack of experience in the diagnosis and treatment of Noonan syndrome in China. This guideline has summarized the clinical manifestation, pathogenesis, diagnostic criteria and treatment for Noonan syndrome, with an aim to improve the diagnostic level and clinical management of patients with this syndrome.

Objective: To analyze clinical manifestations and genetic mutation in a child with severe short stature and other malformations., Methods: The child has undergone history taking and physical examination. Genome DNA was extracted from peripheral blood samples of the proband and her family members. Candidate genes were captured with Agilent SureSelect and sequenced on an Illumina platform. Suspected mutation was verified by Sanger sequencing., Results: The patient, a six-year-and-10-month old girl, presented with non-symmetrical short stature, dysmorphism, abnormalities of limbs and spine, amblyopia of left eye, and cataract of right eye, in addition with frequent respiratory infection and micturition. Laboratory testing suggested 25-hydroxy vitamin D deficiency (18.9 ng/mL). Spine X-ray showed multiple malformations with centrums. Her mother also featured short stature (138 cm). Her aunt had short stature (130 cm) and limb-length discrepancy. Her little brother was 2.5 years old, and his height was 81 cm (-3.4 SD). Exome sequencing revealed a heterozygous mutation c.184C to T (p.Arg62Trp) in the proband and her mother. The same mutation was not found in her father and brother., Conclusion: The patient was diagnosed with X-linked chondrodysplasia punctata 2. Mutation of the EBP gene probably underlied the disease in this family.

Objective: To analyze two Chinese pediatric patients with multiple malformations and growth and development delay., Methods: Both patients were subjected to targeted gene sequencing, and the results were analyzed with Ingenuity Variant Analysis software. Suspected pathogenic variations were verified by Sanger sequencing., Results: High-throughput sequencing showed that both patients have carried heterozygous variants of the CHD7 gene. Patient 1 carried a nonsense mutation in exon 36 (c.7957C>T, p.Arg2653*), while patient 2 carried a nonsense mutation of exon 2 (c.718C>T, p.Gln240*). Sanger sequencing confirmed the above mutations in both patients, while their parents were of wild-type for the corresponding sites, indicating that the two mutations have happened de novo., Conclusion: Two patients were diagnosed with CHARGE syndrome by high-throughput sequencing.

Objective: To identify the genetic cause for a 11-year-old Chinese boy with Meier-Gorlin syndrome (MGS)., Methods: Chromosomal microarray analysis (CMA) was used to detect potential variations, while whole exome sequencing (WES) was used to identify sequence variants. Sanger sequencing was used to confirm the suspected variants., Results: The boy has featured short stature, microtia, small patella, slender body build, craniofacial anomalies, and small testes with normal gonadotropin. A complete uniparental disomy of chromosome 16 was revealed by CMA. WES has identified a novel homozygous mutation c.67A>G (p.Lys23Glu) in ORC6 gene mapped to chromosome 16. As predicted by Alamut functional software, the mutation may affect the function of structural domain of the ORC6 protein., Conclusion: The patient is probably the first diagnosed MGS case in China, who carried a novel homozygous mutation of the ORC6 gene and uniparental disomy of chromosome 16. The effect of this novel mutation on the growth and development needs to be further investigated.

Objective: To investigate the clinical symptoms and potential mutations in the PLA2G6 gene for a child with infantile neuroaxonal dystrophy., Methods: Clinical data of the patient was collected. The coding regions of PLA2G6 gene was subjected to Sanger sequencing using blood DNA from the patient and her parents., Results: The patient has presented with psychomotor regression and hypotonia, followed by development of tetraparesis. A novel homozygous mutation G68A in the PLA2G6 gene was found by DNA sequencing, while her parents were both heterozygous carriers., Conclusion: The psychomotor regression and tetraparesis of the patient was caused by infantile neuroaxonal dystrophy due to a novel homozygous mutation in the PLA2G6 gene, which was inherited from her parents.

Parkinson's disease (PD) is a common degenerative disease of the central nervous system, but no drug has been found to be surely able to protect neurons so far, delay onset or slow progression of the disease. Currently there are a variety of Chinese formulas, single herb medicines, active fractions and monomers showed prophylactic and therapeutic effect on PD animal models. The mechanisms include protection of substantia nigra cells, improvement of neurotransmitter content, anti-oxidation, immune regulation, enhancement of Western medicine efficacy, reduction of side effects, etc. All these mechanisms may play integrated effect and slow disease progression. In particular, Chinese medicine compound may have some advantages in neuroprotective treatment of PD, because a variety of active ingredients can exert multi-links, multi-levels and multi-targets integrated regulation effect on human body. However, the level and standard of Chinese medicine studies on PD animal still need to be improved.

Objective: To investigate the relationship between the subjective sensation of nasal obstruction and the corresponding objective parameters of acoustic rhinometry., Method: Three hundred and sixty-five patients with nasal diseases were divided into two groups: one group included 220 cases with nasal obstruction, and the second group of 145 cases without nasal obstruction. Seventy healthy adults were selected as control. Each one were assessed for nasal minimal cross-sectional area (NMCA), volume of nasal cavity (NV), nasal airway resistance (NAR) and distance of the minimal cross section area from the nostril (DCAN) by using acoustic rhinometry, and the subjective test were performed using the VAS scores. The results were statistically analyzed., Result: NV, DCAN and NAR had a significant difference between nasal obstruct group and control group (P < 0.05). The VAS score had linear correlation with NMCA, NV, DCAN and NAR, and the correlation coefficient were R(NAR) = 0.7385, R(NV) = -0.853 2, R(NMCA) = -0.745 4 and R(DCAN) = 0.369 7, respectively., Conclusion: Since NAR and NV coincide with the subjective perception of patients with nasal obstruction, they can be used as the sensitive parameters to evaluate subjective symptoms of patients.