[A multicenter prospective study on early identification of refractory Mycoplasma pneumoniae pneumonia in children].

Objective: To explore potential predictors of refractory Mycoplasma pneumoniae pneumonia (RMPP) in early stage. Methods: The prospective multicenter study was conducted in Zhejiang, China from May 1st, 2019 to January 31st, 2020. A total of 1 428 patients with fever >48 hours to <120 hours were studied. Their clinical data and oral pharyngeal swab samples were collected; Mycoplasma pneumoniae DNA in pharyngeal swab specimens was detected. Patients with positive Mycoplasma pneumoniae DNA results underwent a series of tests, including chest X-ray, complete blood count, C-reactive protein, lactate dehydrogenase (LDH), and procalcitonin. According to the occurrence of RMPP, the patients were divided into two groups, RMPP group and general Mycoplasma pneumoniae pneumonia (GMPP) group. Measurement data between the 2 groups were compared using Mann-Whitney U test. Logistic regression analyses were used to examine the associations between clinical data and RMPP. Receiver operating characteristic (ROC) curves were used to analyse the power of the markers for predicting RMPP. Results: A total of 1 428 patients finished the study, with 801 boys and 627 girls, aged 4.3 (2.7, 6.3) years. Mycoplasma pneumoniae DNA was positive in 534 cases (37.4%), of whom 446 cases (83.5%) were diagnosed with Mycoplasma pneumoniae pneumonia, including 251 boys and 195 girls, aged 5.2 (3.3, 6.9) years. Macrolides-resistant variation was positive in 410 cases (91.9%). Fifty-five cases were with RMPP, 391 cases with GMPP. The peak body temperature before the first visit and LDH levels in RMPP patients were higher than that in GMPP patients (39.6 (39.1, 40.0) vs. 39.2 (38.9, 39.7) ℃, 333 (279, 392) vs. 311 (259, 359) U/L, both P<0.05). Logistic regression showed the prediction probability π=exp (-29.7+0.667×Peak body temperature (℃)+0.004×LDH (U/L))/(1+exp (-29.7+0.667×Peak body temperature (℃)+0.004 × LDH (U/L))), the cut-off value to predict RMPP was 0.12, with a consensus of probability forecast of 0.89, sensitivity of 0.89, and specificity of 0.67; and the area under ROC curve was 0.682 (95%CI 0.593-0.771, P<0.01). Conclusion: In MPP patients with fever over 48 to <120 hours, a prediction probability π of RMPP can be calculated based on the peak body temperature and LDH level before the first visit, which can facilitate early identification of RMPP.

[The predictive value of microvascular obstruction for adverse left ventricular remodeling after primary percutaneous coronary intervention in patients with acute ST-elevation myocardial infarction: a prospective study].

Objectives: Microvascular obstruction (MVO) is a specific cardiac magnetic resonance (CMR) imaging feature in patients with acute myocardial infarction. The purpose of this study was to elucidate the predictive value of MVO in left ventricular adverse remodeling after primary percutaneous coronary intervention (PCI) in patients with acute ST-elevation myocardial infarction (STEMI). Methods: A total of 167 patients with STEMI undergoing primary PCI in the Chinese PLA General Hospital from 2016 to 2020 were enrolled in this prospective cohort study, the average age of study patients was 57±10 years old, with 151 males (90.4%) and 16 females (9.6%). The patients were divided into the MVO group (n=81) and non-MVO group (n=86) according to the presence or absence of MVO on CMR imaging, respectively. The primary endpoint of the study was the occurrence of left ventricular adverse remodeling, which was defined as an increase in left ventricular end diastolic volume (LVEDV) by >20% at 6 months after primary PCI compared with the baseline. Patients who completed follow-up were diagnosed as left ventricular adverse remodeling or no left ventricular adverse remodeling according to CMR. The baseline data, perioperative data, and related data of end points were compared between the MVO group and non-MVO group. Finally, the predictive value of MVO in left ventricular adverse remodeling was calculated by receiver operating characteristic curve analysis. Results: In the baseline data, preoperative thrombolysis in myocardial infarction (TIMI) flow (χ2=13.74, P=0.003) and postoperative TIMI flow (χ2=14.87, P=0.001) were both obviously decreased in the MVO group. After 6 months of follow-up, the incidence of left ventricular adverse remodeling in the MVO group was significantly higher than that in the non-MVO group [37.0%(27/73) vs. 18.9%(14/74), χ2=5.96, P=0.015]. The left ventricular end systolic volume at 6 months post infarction in the MVO group was significantly larger than that in the non-MVO group [(94±32) vs. (68±20) ml, t=-5.98, P<0.001], as well as the LVEDV [(169±38) vs. (143±29) ml, t=-4.74, P<0.001]. Receiver operating characteristic curve showed that the area under the curve of MVO size for predicting left ventricular adverse remodeling was 0.637. Conclusion: The risk of left ventricular adverse remodeling is significantly increased in patients with MVO after primary PCI for acute STEMI.

[Long noncoding RNA H19 promotes vascular calcification by repressing the Bax inhibitor 1/optic atrophy 1 pathway].

OBJECTIVE: To investigate whether long noncoding RNA H19 (lncRNA H19) induces vascular calcification by promoting calcium deposition, osteogenic differentiation and apoptosis via inhibiting the Bax inhibitor 1/optic atrophy 1 (BI-1/ OPA1) pathway. METHODS: ß-glycerophosphate and calcium chloride were used to induce calcification in rat vascular smooth muscle cells (VSMCs), and the effects of siH19, alone or in combination with BI-1 or OPA1 knockdown, on calcification of the cells were investigated. Osteogenic differentiation was assessed by measuring Runt-related transcription factor 2 (Runx-2) and bone morphogenetic protein 2 (BMP-2) expression with Western blotting, and cell apoptosis was evaluated by TUNEL staining and Western blotting. An ApoE-/- diabetic mouse model with high-fat feeding for 32 weeks were given an intraperitoneal injection of siH19, and the changes in calcium deposition in the aortic arch were examined using Alizarin red S staining and von Kossa staining. RESULTS: In rat VSMCs with calcification, the expression of lncRNA H19 was significantly increased, and the expressions of BI- 1 and OPA1 were significantly decreased. Downregulation of lncRNA H19 significantly increased the expressions of BI-1 and OPA1 proteins in the cells, and BI-1 knockdown further reduced OPA1 expression (P<0.001). The cells treated with siH19 showed total disappearance of the calcified nodules with significantly reduced expressions of Runx-2, BMP-2 and cleaved caspase-3 and a lowered cell apoptosis rate (P<0.001). Calcified nodules were again observed in the cells with lncRNA H19 knockdown combined with BI-1 or OPA1 knockdown, and the expressions of Runx-2, BMP-2, cleaved-caspase-3 and cell apoptosis rate all significantly increased (P<0.001). In the diabetic mouse model with high-fat feeding, siH19 treatment significantly reduced the calcification area and increased mRNA expressions of BI-I and OPA1 in the aortic arch. CONCLUSION: LncRNA H19 promotes vascular calcification possibly by promoting calcium deposition, osteogenic differentiation and cell apoptosis via inhibiting the BI-1/OPA1 pathway.

[Protection of side-branch ostium by the jailed balloon technique validated by three-dimensional optical coherence tomography].

Objective: To evaluate the protective effect of jailed balloon technique on side branch (SB) ostium using three-dimensional optical coherence tomography(OCT). Methods: This is a retrospective study. Consecutive coronary disease patients with coronary artery bifurcation lesions who underwent percutaneous coronary intervention (PCI) and completed pre-and post-procedural OCT examinations at the Chinese People's Liberation Army General Hospital from September 2019 to March 2022 were enrolled. Patients were divided into the jailed balloon technique group and the unprotected group according to the options applied for the SB. The SB ostium area difference was calculated from OCT images (SB ostium area difference=post-PCI SB ostium area-pre-PCI SB ostium area). The SB ostium area differences were compared between the two groups and compared further in the subgroup of true bifurcation lesions and non-true bifurcation lesions. In the jailed balloon group, the SB ostium area difference was compared between the active jailed balloon technique and the conventional jailed balloon technique, between the jailed balloon>2.0 mm diameter and the jailed balloon≤2.0 mm diameter, and between the higher balloon pressure (>4 atm, 1 atm=101.325 kPa) and the lower balloon pressure (≤4 atm). Multivariate linear regression analysis was used to explore the correlation between the technical parameters of the jailed balloon technique and the SB protection effect. Results: A total of 176 patients with 236 bifurcation lesions were enrolled, aged (60.7±9.3) years, and there were 128 male patients (72.7%). There were 67 patients in the jailed balloon technique group with 71 bifurcation lesions and 123 patients in the unprotected group with 165 bifurcation lesions. Fourteen patients had 2 to 3 lesions, which were treated in different ways, so they appeared in the unprotected group and the jailed balloon technique group at the same time. The area difference in SB ostium was greater in the jailed balloon group than in the unprotected group (0.07 (-0.43, 1.05)mm2 vs.-0.33 (-0.83, 0.26)mm2, P<0.001), and the results were consistent in the true bifurcation lesion subgroup (0.29 (-0.35, 0.96)mm2 vs.-0.26 (-0.64, 0.29)mm2, P=0.004), while the difference between the two groups in the non-true bifurcation lesion subgroup was not statistically significant (P=0.136). In the jailed balloon technique group, the SB ostium area difference was greater in patients treated with the active jailed balloon technique than in those treated with the conventional jailed balloon technique ((0.43±1.36)mm2 vs. (-0.22±0.52)mm2, P=0.013). The difference in SB ostium area was greater in those using>2.0 mm diameter jailed balloons than in those using≤2.0 mm diameter jailed balloons (0.25 (-0.51, 1.31) mm2 vs.-0.01 (-0.45, 0.63) mm2, P=0.020), while SB ostium area difference was similar between those endowed with higher balloon pressure (>4 atm) compared to those with lower balloon pressure (≤4 atm) (P=0.731). Multivariate linear regression analysis showed that there was a positive correlation between jailed balloon diameter and SB ostium area difference (r=0.344, P=0.019). Conclusions: The jailed balloon technique significantly protects SB ostium, especially in patients with true bifurcation lesions. The active jailed balloon technique and larger diameter balloons may provide more protection to the SB.

[Bax inhibitor 1 inhibits vascular calcification in mice by activating optic atrophy 1 expression].

OBJECTIVE: To investigate the effects of Bax inhibitor 1 (BI- 1) and optic atrophy protein 1 (OPA1) on vascular calcification (VC). METHODS: Mouse models of VC were established in ApoE-deficient (ApoE-/-) diabetic mice by high-fat diet feeding for 12 weeks followed by intraperitoneal injections with Nε-carboxymethyl-lysine for 16 weeks. ApoE-/- mice (control group), ApoE-/- diabetic mice (VC group), ApoE-/- diabetic mice with BI-1 overexpression (VC + BI-1TG group), and ApoE-/- diabetic mice with BI-1 overexpression and OPA1 knockout (VC+BI-1TG+OPA1-/- group) were obtained for examination of the degree of aortic calcification using von Kossa staining. The changes in calcium content in the aorta were analyzed using ELISA. The expressions of Runt-related transcription factor 2 (RUNX2) and bone morphogenetic protein 2 (BMP-2) were detected using immunohistochemistry, and the expression of cleaved caspase-3 was determined using Western blotting. Cultured mouse aortic smooth muscle cells were treated with 10 mmol/L ß-glycerophosphate for 14 days to induce calcification, and the changes in BI-1 and OPA1 protein expressions were examined using Western blotting and cell apoptosis was detected using TUNEL staining. RESULTS: ApoE-/- mice with VC showed significantly decreased expressions of BI-1 and OPA1 proteins in the aorta (P=0.0044) with obviously increased calcium deposition and expressions of RUNX2, BMP-2 and cleaved caspase-3 (P= 0.0041). Overexpression of BI-1 significantly promoted OPA1 protein expression and reduced calcium deposition and expressions of RUNX2, BMP-2 and cleaved caspase-3 (P=0.0006). OPA1 knockdown significantly increased calcium deposition and expressions of RUNX2, BMP-2 and cleaved caspase-3 in the aorta (P=0.0007). CONCLUSION: BI-1 inhibits VC possibly by promoting the expression of OPA1, reducing calcium deposition and inhibiting osteogenic differentiation and apoptosis of the vascular smooth muscle cells.

[Bax inhibitor-1 inhibits calcification of vascular smooth muscle cells in vitro].

OBJECTIVE: To investigate the effect of Bax inhibitor-1(BI-1)on calcification of vascular smooth muscle cells(VSMCs). METHODS: VSMCs were isolated from the thoracic aorta of SD rats.VSMCs or BI-1-overexpressing VSMCs(transfected with a BI-1-overexpressing plasmid) were cultured in normal medium or calcified medium containing ß-glycerophosphate and calcium chloride, and the cell calcification was examined with Alizarin red staining.Enzyme-linked immunosorbent assay was used to determine the intracellular calcium content and alkaline phosphatase activity.The expression levels of Runt-related transcription factor 2 (RUNX2), bone morphogenetic protein 2 (BMP-2) and caspase-3 were detected with Western blotting. RESULTS: After 14 days of culture in the calcified medium, the VSMCs showed significantly reduced expression of BI-1 protein(P=0.001).BI-1 overexpression in the VSMCs caused a significant reduction of calcium level and alkaline phosphatase activities(P=0.0006) and lowered the expression levels of RUNX2 and BMP-2 (P=0.0001) in the cells.The VSMCs with induced calcification exhibited a significantly increased apoptosis rate, but BI-1 overexpression obviously inhibited VSMC apoptosis in the calcified medium (P=0.0003). CONCLUSION: BI-1 may attenuate vascular calcification by inhibiting calcium deposition, osteogenic differentiation and apoptosis.

Epidemiologic and clinical characteristics of 91 hospitalized patients with COVID-19 in Zhejiang, China: a retrospective, multi-centre case series.

BACKGROUND: Recent studies have focused on initial clinical and epidemiological characteristics of the coronavirus disease 2019 (COVID-19), which is the mainly revealing situation in Wuhan, Hubei. AIM: This study aims to reveal more data on the epidemiological and clinical characteristics of COVID-19 patients outside of Wuhan, Zhejiang, China. DESIGN: This study was a retrospective case series. METHODS: Eighty-eight cases of laboratory-confirmed and three cases of clinically confirmed COVID-19 were admitted to five hospitals in Zhejiang province, China. Data were collected from 20 January 2020 to 11 February 2020. RESULTS AND DISCUSSION: Of all 91 patients, 88 (96.70%) were laboratory-confirmed COVID-19 with throat swab samples that tested positive for SARS-Cov-2, three (3.30%) cases were clinically diagnosed. The median age of the patients was 50 (36.5-57) years, and female accounted for 59.34%. In this sample, 40 (43.96%) patients had contracted the disease from local cases, 31 (34.07%) patients had been to Wuhan/Hubei, eight (8.79%) patients had contacted with people from Wuhan, and 11 (12.09%) patients were diagnosed after having flown together in the same flight with no passenger that could later be identified as the source of infection. In particular within the city of Ningbo, 60.52% cases can be traced back to an event held in a temple. The most common symptoms were fever (71.43%), cough (60.44%) and fatigue (43.96%). The median of incubation period was 6 (interquartile range 3-8) days and the median time from the first visit to a doctor to the confirmed diagnosis was 1 (1-2) days. According to the chest computed tomography scans, 67.03% cases had bilateral pneumonia. CONCLUSIONS: Social activity cluster, family cluster and flying alongside with persons already infected with COVID-19 were how people got infected with COVID-19 in Zhejiang.

Understanding of metal-insulator transition in VO2 based on experimental and theoretical investigations of magnetic features.

The metal-insulator transition temperature Tc in VO2 is experimentally shown to be almost the same as a magnetic transition temperature Tm characterized by an abrupt decrease in susceptibility, suggesting the evidence of the same underlying origin for both transitions. The measurement of susceptibility shows that it weakly increases on cooling for temperature range of T > Tm, sharply decreases near Tm and then unusually increases on further cooling. A theoretical approach for such unusual observations in susceptibility near Tm or below is performed by modeling electrons from each two adjacent V4+ ions distributed along V-chains as a two-electron system, which indicates that the spin exchange between electrons could cause a level splitting into a singlet (S = 0) level of lower energy and a triplet (S = 1) level of higher energy. The observed abrupt decrease in susceptibility near Tm is explained to be due to that the sample enters the singlet state in which two electrons from adjacent V4+ ions are paired into dimers in spin antiparallel. By considering paramagnetic contribution of unpaired electrons created by the thermal activation from singlet to triplet levels, an expression for susceptibility is proposed to quantitatively explain the unusual temperature-dependent susceptibility observed at low temperatures. Based on the approach to magnetic features, the observed metal-insulator transition is explained to be due to a transition from high-temperature Pauli paramagnetic metallic state of V4+ions to low-temperature dimerized state of strong electronic localization.

[Study on proteomic profiling changes of workers exposed to methylbenzene and healthy individuals].

Objective: This study focused on the proteomicchanges between workers exposed to methylbenzene (WMB) and healthy individuals (HI) . Methods: The serum of WMB and HI was collected and the unmarked label free mass spectrometry was utilized for protein identification and quantitative comparison. The differentlyexpressed proteins in WMB and the HI were screened, followed by the analysis of protein and biological functions by bioinformatics tools. Results: Thirty nine proteins were differently expressed between WMB and HI. Compared with HI, 24 proteins were up regulated and 15 proteins were down regulated over 2 fold change in WMB. Theseproteins were mainly involved in signal transduction, serine endopeptidase activity, inflammatory response, protein modification, stress reaction, coagulation reaction and so on. Conclusion: The differently expressed proteins provide a potential protein marker for the health assessment of WMB and early diagnosis of methylbenzene poisioning and expand our understanding of the molecular mechanism of methylbenzene intoxication.

[Efficacy of microwave ablation in treatment of hepatocellular carcinoma within the Milan criteria: a report of 696 cases].

Objective: To investigate the efficacy of microwave ablation in the treatment of hepatocellular carcinoma (HCC) within the Milan criteria and to investigate the differences in clinical efficacy of microwave ablation in tumors with different sizes. Methods: A retrospective analysis was performed on the clinical data of the patients with HCC within the Milan criteria who received microwave ablation in our hospital from January 2011 to January 2013. The complete ablation rate, incidence rate of major complications, recurrence rate, and overall survival rate were analyzed and the treatment outcomes were compared between two groups with different tumors sizes. The patients were followed up for 3.4-61.8 months. The Kaplan-Meier method was used to calculate overall survival rate, local recurrence rate, and distant recurrence rate. Comparison of rates between groups was made by the chi-square test and comparison of survival rates between groups was made by the log-rank test. Results: A total of 696 patients with HCC within the Milan criteria involving 801 tumors were included in this study. The complete ablation rate was 93.8% (653/696) and the incidence rate of major complications was 1.7% (12/696). The median survival time was 59.6 months and the 1-, 2-, and 3-year overall survival rates were 94.8%, 82.2%, and 71.7%, respectively. The local recurrence rate was 13.4% (93/696) and the rate of intrahepatic distant metastasis was 40.1% (279/696). The overall intrahepatic recurrence rate was 48.1% (335/696), and the 1-, 2-, and 3-year recurrence rates were 22.9%, 38.4%, and 46.8%, respectively. There were no significant differences in complete ablation rate, incidence rate of major complications, and overall survival rate between the two groups with different tumor sizes (diameters≤3 cm and 3-5 cm) (P = 0.12; P = 0.61; P = 0.61). Conclusion: Microwave ablation is a safe and effective treatment modality for HCC within the Milan criteria. And there are no significant differences in safety, effectiveness, and long-term efficacy of microwave ablation between the two groups with different tumor sizes (diameters ≤3 cm and 3-5 cm). However, if the operator's experience is not rich and cannot accurately use conformal ablation and make an individualized treatment, the tumors with a diameter of 3-5 cm should be carefully treated using microwave ablation to avoid residual tumor after treatment.

Role of carboxylic acid groups in the reduction of nitric oxide by carbon at low temperature, as exemplified by graphene oxide.

Graphene oxide (GO) was utilized to investigate the role of carboxylic acid groups in the reduction of nitric oxide (NO) for the first time. As a result, GO with sufficient carboxylic acid groups reduced 45% of NO at 100 °C. However, GO without these oxygen-containing groups barely reduced NO (lower than 5%) under the same conditions. After reduction of NO, the carboxylic acid group content on GO decreased from 8.32 to 5.22 mmol g-1. Simultaneously, the anhydride group content increased from 0.14 to 0.28 mmol g-1. FTIR spectroscopy also indicated that the carboxylic acid groups transformed into anhydride and lactone groups. Moreover, both transient kinetics and TG-MS studies demonstrated that reactive intermediates formed during the reaction between NO and GO at 100 °C. Based on these results, it was proposed that the carboxylic acid groups participated in NO reduction by consumption and regeneration. This mechanism explains why carbon is usually an effective reductant and catalyst support for NO removal at low temperature.

The effect of maternal low flow oxygen administration during the second stage of labour on umbilical cord artery pH: a randomised controlled trial.

OBJECTIVE: To assess the effect of maternal low flow oxygen administration during the second stage of labour on umbilical cord artery pH. DESIGN: A randomised controlled trial. SETTING: A tertiary teaching hospital in China. POPULATION: Women in the second stage of labour with no complications. METHODS: About 443 women were randomly allocated to receive either supplemental oxygen at a flow rate of 2 l/min or a sham supplementation by nasal cannula. Healthcare providers, women and outcome assessors were blinded to allocation. MAIN OUTCOME MEASURES: Umbilical cord artery pH and fetal heart rate (FHR) pattern. RESULTS: Baseline characteristics were similar between the two groups. There were no significant differences between the two groups in the umbilical cord artery pH [median 7.261, interquartile range (IQR) 7.228-7.295 versus 7.266 (IQR 7.232-7.297), P = 0.64], the proportion with pH less than 7.2 [30/219 versus 34/224, P = 0.66, RR (relative risk) 0.9, 95% CI 0.57-1.42], and the proportion with normal FHR pattern (147/219 versus 153/224, P = 0.79, RR 0.98, 95% CI 0.86-1.12). Maternal partial pressure of dissolved oxygen was significantly higher in the oxygen group than in the sham group [median 150.0 mmHg (IQR 142.6-156.7) versus 112.0 (IQR 104.8-118.3), P < 0.001], whereas carbon dioxide was significantly lower in the oxygen group than in the sham group (mean difference -1.1, 95% CI -2.1 to -0.1, P = 0.03). CONCLUSION: The use of 2 l/min maternal oxygen during the second stage of labour did not adversely affect either the umbilical artery pH or the FHR pattern distribution. TWEETABLE ABSTRACT: No difference in abnormal fetal acid base or normal heart rate if maternal O2 given, randomised trial finds.

[Analysis of newborn screening for galactosemia and genotype-phenotype of confirmed galatosemia cases].

Objective: To investigate the prevalence of galactosemia(GAL), and the characteristics of genotype and phenotype of newborns who were confirmed with GAL in newborn screening in Zhejiang province. Method: The number of all live births, newborn screened infants and all clinical data of confirmed newborns with GAL from October 2013 to March 2015 were retrospectively analyzed by reviewing the data of Zhejiang Province screening center database. And the characteristics of genes and the clinical data of GAL cases who were confirmed by correlative gene test and enzyme activity measurement were analyzed. Result: The prevalence of GAL in Zhejiang province was 1/189 857. Among them, there was 1 case confirmed with GAL typeⅠ (prevalence, 1/759 428), with mutations of c. 904+ 1G>T and c. 687G>A, the enzyme activity of galactose-1-phosphate uridyltransferase (GALT) was 56.4% of controls. And there was 1 case of GAL typeⅡ(prevalence, 1/759 428), with mutations of c. 85G>T and c. 502G>A. There were 2 cases confirmed with GAL type Ⅲ(prevalence, 1/379 714), with mutations of c. 505C>T, c. 452G>A, c. 280G>A and c. 925G>A, the enzyme activity of UDP-galactose-4'-epimerase (GALE) were 42% and 38% of controls, respectively. All cases had different abnormal biochemical marks of liver function, and 1 case had combined hyperlactacidemia or hyperammonemia or increase of multiple kinds of amino acids, respectively. The newborn of GAL type Ⅱ had phacoscotasmus before treatment. All the cases were fed with lactose free milk powder, and all the abnormal parameters were improved during following up. Conclusion: The disease of GAL is rare in Zhejiang province, and its genotype distribution is scattered with comparatively mind clinical manifestations, and the cases with early treatment with lactose free milk powder have good prognosis. All cases needed to be treated and followed up for a life-long time. It is recommended that the high risk cases with GAL should be screened as soon as possible.

[Clinical, biochemical and gene mutation characteristics of short chain acyl-coenzyme A dehydrogenase deficiency by neonatal screening].

Objective: To investigate the incidence, clinical, biochemical and gene mutation characteristics of short chain acyl-coenzyme A dehydrogenase deficiency (SCADD). Method: From January, 2009 to October, 2015, a retrospective analysis of the urine organic acids and acyl-coenzyme A dehydrogenase (ACADS) gene mutation characteristics of patients diagnosed as SCADD by newborn screening using tandem mass spectrometry in Department of Genetics and Metabolism (Newborn screening Center of Zhejiang Province), Children's Hospital, Zhejiang University School of Medicine. Dietary guidance, life management and supplementation of L-carnitine were conducted, and growth and intelligence development were observed during follow-up among the SCADD patients. Result: A total of 1 430 024 neonates, seventeen cases were diagnosed with SCADD with an incidence of 1/84 117. All patients had no clinical symptoms, and intelligence and physical development were normal. Blood butylacyl-carnitine (C4) levels and the ratios increased, C4 0.713.14 µmol/L(reference value 0.03-0.48 µmol/L), C4/C2 0.07-0.23(reference value 0.01-0.04), C4/C3 0.65-2.04(reference value 0.05-0.39). Thirteen with increased urinary ethyl malonic acid (9.30-90.99 mg/g creatinine (reference value 0-6.20 mg/g creatinine )), one patient was accompanied by increased methyl succinic acid (12.33 mg/g creatinine(reference value 0-6.40 mg/g creatinine)), one subject with increased acetylglycine (3.52 mg/g creatinine(reference value 0-0.70 mg/g creatinine)). A total of 13 known mutations were detected in the ACADS gene, 1 homozygous mutation (c.1031A>G), the others are compound heterozygous mutations. One frameshift mutation (c.508_509delGC) and 12 missense mutations were detected. Common mutation were c. 1031A>G(35.3%), c. 164C>T(20.6%) and c. 991G>A(11.8%). SCADD in newborn screening program had no clinical symptoms and normal growth development after 8-42 months follow-up. Conclusion: Cases with SCADD had no clinical symptoms with an incidence of 1/84117. The c. 164C>T and c. 1031A>G may be the common mutations.