Neonatal Smith-Kingsmore syndrome: case report and literature review / 中国新生儿科杂志

Objective:To study the clinical and genetic features of neonatal Smith-Kingsmore syndrome (SKS).Methods:The clinical data of a newborn with SKS admitted to our hospital in November 2021 were reviewed. Using "Smith-Kingsmore", "rapamycin gene", "newborn", "premature infant", "the mammalian target of rapamycin", "MTOR", "mTOR", "Smith-Kingsmore syndrome", "megalencephaly", "macrocephaly" and "hemimegalencephaly" as keywords, databases including CNKI, Wanfang Database, VIP database, PubMed, Embase, Web of Science and the Cochrane Library were searched from the date of establishment to January 1, 2022. The clinical and genetic features of neonatal SKS from published literature were summarized.Results:The case admitted to our hospital was a male preterm infant. The presenting symptoms were groan and hypotonia. The facial abnormalities included macrocrania, ocular hypertelorism, depressed nasal bridge and low-set ears. Brain MRI showed lateral ventricle enlargement. Whole-genome sequencing (WGS) showed mTOR gene nonsense heterozygous mutation (NM_004958.4:c.7255G>A:p.Glu2419Lys). Neither father nor mother had any pathogenic gene mutations. The infant had seizure at 2-month and phenobarbital was effective reducing seizure. Gross motor delay was present at 3-month. Sixteen related articles were retrieved, including eight articles with 10 neonatal cases. Among them, 6 cases were male. The main clinical features were megalencephaly or hemimegalencephaly (9/10), facial developmental malformation (8/10), hypotonia (6/10), large-for-gestational age (LGA) infants (5/10), cerebral ventricle dilation (4/10) and abnormal corpus callosum (4/10). All the gene mutations were missense mutations, including c.5395G>A(p.Glu1799Lys) mutation in 5 cases, c.4448G>T(p.Cys1483Phe) mutation in 1 case, c.4448G>T(p.Cys1483Tyr) mutation in 1 case, c.7235A>T(p.Asp2412Val) mutation in 1 case, c.5663T>G(p.Phe1888Cys) mutation in 1 case, c.5390C>T(p.Thr1799IIe) mutation in 1 case.Conclusions:The clinical phenotypes of neonatal SKS are diverse, including megalencephaly, facial malformation, LGA and hypotonia. The brain MR findings included (hemi) megalencephaly, cerebral ventricle dilation and corpus callosum hypoplasia. Most of the gene mutations are missense mutations and c.5395G>A(p.Glu1799Lys) is the hotspot.

Early risk factors for the failure of the INSURE strategy in premature infants with respiratory distress syndrome / 中国新生儿科杂志

Objective:To study the early risk factors for the failure of INtubation-SURfactant-Extubation (INSURE) strategy in preterm infants with respiratory distress syndrome (RDS).Methods:From November 2016 to October 2020, preterm infants with gestational age (GA) <34 weeks admitted to our hospital were enrolled in this study. Infants required invasive ventilation within 72 hours after extubation were assigned into INSURE failure group and other infants INSURE success group. SPSS 25.0 was used to compare the clinical data of the two groups and Logistic regression analysis was used to analyze the independent risk factors of INSURE failure.Results:The incidence of INSURE strategy failure was 25.0% (34/136). The antenatal dexamethasone use, GA, birth weight, 1 min Apgar score, 5 min Apgar score, respiratory index (PaO 2/FiO 2) and mean hemoglobin (Hb) in INSURE failure group were significantly lower than INSURE success group ( P<0.05). INSURE failure group had significantly delayed use of first-time pulmonary surfactant (PS), longer duration of positive pressure ventilation resuscitation, higher respiratory score in Apgar, higher procalcitonin (PCT) level, more placental chorioamnionitis and more RDS radiological grade ≥3 cases than INSURE success group ( P<0.05). Logistic regression analysis showed that respiratory score ≥8 ( OR=10.609, 95% CI 2.630~42.797, P=0.001), RDS radiological grade ≥ 3 ( OR=8.813, 95% CI 2.022~38.423, P=0.004) and Hb<145 g/L ( OR=9.074, 95% CI 1.771~46.147, P=0.008) were independent risk factors for INSURE failure. And antenatal dexamethasone use ( OR=0.270, 95% CI 0.075~0.978, P=0.046) was a protective factor for INSURE failure. Conclusions:Respiratory score ≥8 in Apgar, RDS radiological grade ≥3, Hb<145 g/L and the insufficient use of antenatal dexamethasone are independent risk factors for INSURE failure.

Baeyer-Villiger monooxygenases in the biosynthesis of microbial secondary metabolites / 生物工程学报

Baeyer-Villiger monooxygenases, a well-studied class of flavin-dependent enzymes, catalyze the conversion of ketones to lactones or esters and the oxygenation of heteroatoms, which possesses great practical prospect in synthetic chemistry and biocatalysis. In this review, we focus on Baeyer-Villiger oxidations involved in biosynthesis of microbial secondary metabolites and discuss the characteristics of these Baeyer-Villiger oxidations and Baeyer-Villiger monooxygenases, to provide reference for the protein engineering of Baeyer-Villiger monooxygenases.

Optimization of the Extraction Process of Total Flavonoids from Pueraria lobata by Uniform Design / 中国药房

OBJECTIVE:To optimize the extraction conditions of total flavones from Pueraria Lobata by ultrasonic method.METHODS:The uniform design method was applied to investigate the effects of alcohol content,the quantity of solvent,extraction time,extraction temperature and the extraction times on the result of extraction.The content of total flavone of Pueraria Lobata was determined by ultraviolet-visible spectrophotometry.The extraction conditions were optimized with the extraction yield and the mass fraction of total flavone of Pueraria lobata in the extract as indexes.RESULTS:The optimal extraction conditions were as follows:extracting with 75% alcohol(20 mL?g-1) for 40 min(extraction time) at 68 ℃(extraction temperature) for a total of 5 times.CONCLUSION:The extraction process is reasonable and feasible and it provides theoretic basis for the industrialized production.