Objective:To explore the effect of Notch1 signaling on regulatory T cells and its roles in vascular damage in patients with Kawasaki disease (KD).Methods:A total of 42 children with KD were enrolled in the present study from March 2019 to June 2020, as 32 age-matched healthy children were recruited as control. The proportions of CD4 +CD25 hiFoxp 3+ regulatory T cells (Treg) and expressions of transcription factor forkhead box protein 3 (Foxp3), cytotoxic T lymphocyte associated antigen-4 (CTLA4), glucocorticoid-induced tumor necrosis factor receptor (GITR), and Notch1 protein were evaluated by flow cytometry. Chromatin immunoprecipitation was conducted to detect acetylation level of histone H4 (H4Ac) associated with the promoter of Foxp3 gene and its binding abilities of Notch1 intracellular domain 1 (NICD1), recombination signal binding protein for immunoglobulin kappa J region (RBP-J) and p300 in CD4 + T cells. Transcription levels of Foxp3, presenilin 1 (PSEN1), mastermind like transcriptional coactivator 1 (MAML1), and RBP-J in CD4 + T cells were determined by real-time polymerase chain reaction (PCR). Concentrations of interleukin (IL)-10 and transforming growth factor-β (TGF-β) in plasma and culture supernatant stimulated with Jagged1 were measured by enzyme linked immunosorbent assay. Independent-sample t-test, Pearson correlation analysis was used as the statistical method in this study. Results:① The frequencies of Treg in acute KD patients decreased significantly [(4.3±1.5)% vs (7.9±2.9)%; t=6.41, P<0.001], as protein levels of Foxp3, CTLA4 and GITR and concentrations of IL-10 and TGF-β in plasma reduced remarkably in acute KD patients ( t=6.87, P<0.001; t=4.26, P<0.001; t=7.88, P<0.001; t=8.42, P<0.001; t=13.01, P<0.001). All parameters afore-mentioned in patients combined with coronary artery lesions (CAL) were lower than those of patients without coronary artery lesions (NCAL) ( t=5.83, P<0.001; t=3.83, P<0.001; t=3.28, P=0.002; t=5.05, P<0.001; t=5.96, P<0.001; t=5.17, P<0.001), and increased after therapy ( t=7.13, P<0.001; t=6.10, P<0.001; t=4.31, P<0.001; t=6.55, P<0.001; t=7.40, P<0.001; t=7.84, P<0.001). ② H4Ac associated with promoter of Foxp3 gene and the binding abilities of NICD1 and p300 in acute KD patients were lower than those of the controls ( t=10.25, P<0.001; t=6.93, P<0.001; t=6.75, P<0.001), and increased remarkably after therapy ( t=7.72, P<0.001; t=4.16, P<0.001; t=5.76, P<0.001). Meanwhile, the three items in CAL group were found to be less than those of NCAL group ( t=6.08, P<0.001; t=2.66, P=0.011; t=6.02, P<0.001). Pearson correlation analysis showed a positive correlation between H4Ac associated with Foxp3 promoter and its mRNA level in acute KD patients ( r=0.47, P<0.001). No statistical significant difference about the binding ability of RBP-J with Foxp3 promoter were found among the groups ( t=0.57, P>0.05; t=0.61, P>0.05; t=1.20, P>0.05). ③ Protein level of Notch1 and the expressions of PSEN1, MAML1 and RBP-J mRNA in CD4 + T cells from acute KD patients were down-regulated remarkably ( t=5.28, P<0.001; t=6.31, P<0.001; t=11.78, P<0.001; t=8.06, P<0.001), and restored after therapy ( t=4.77, P<0.001; t=6.43, P<0.001; t=11.95, P<0.001; t=7.79, P<0.001). In parallel, the four indexes aforementioned of CAL group were lower than those of NCAL group ( t=3.16, P=0.003; t=4.13, P<0.001; t=5.42, P<0.001; t=4.05, P<0.001). Upon rhJagged1 stimulation for 48 hours, H4Ac level of Foxp3 promoter and its binding abilities with NICD1 and p300 in CD4 + T cells in KD patients and control group was significantly higher than those of untreated group [(KD: t=15.36, P<0.001; t=7.25, P<0.001; t=14.29, P<0.001), (Ctrl: t=7.87, P<0.001; t=5.71, P<0.001; t=8.74, P<0.001)], as the binding ability of RBP-J with Foxp3 promoter increased slightly without statistically significant difference (KD: t=1.11, P>0.05; Ctrl: t=1.37, P>0.05). Simultaneously, H4Ac level of Foxp3 promoter and its binding abilities with NICD1 and p300 in KD group were still lower than those of the control group after stimulation ( t=3.86, P<0.001; t=3.42, P=0.001; t=2.85, P=0.006). ④ After incubation of PBMC from heathy children with KD serum, the proportion of Treg cells, protein level of Foxp3 and expressions of Notch1 and RBP-J in CD4 + T cells in the group treated with IVIG increased significantly compared with the untreated group ( t=7.10, P<0.001; t=10.16, P<0.001; t=8.06, P<0.001; t=9.77, P<0.001), as well as H4Ac level of Foxp3 promoter and its binding abilities with NICD1 in the group treat with IVIG were also higher than the latter ( t=7.24, P<0.001; t=8.24, P<0.001). Conclusion:Insufficiency and impaired function of Treg caused by aberrant Notch1 signaling may be the important factor contributing to immune dysfunction and vascular damage in KD.

Objective:To investigate the changes and significance of granulocyte-like myeloid-derived suppressor cells (G-MDSC) in the acute phage of Kawasaki disease (KD).Methods:Forty-two children with acute KD were enrolled in the present study and 32 age-matched healthy children were selected as control group. The proportion of HLA-DR -CD11b + CD33 + CD14 -CD15 + G-MDSC, the concentration of reactive oxygen species (ROS) and the expression of arginase-1 (Arg-1), programmed death-ligand 1 (PD-L1), cytotoxic T lymphocyte associated protein 4 (CTLA4), glycoprotein 130 (gp130) and phosphorylated signal transducer and activator of transcription 3 (pSTAT3) at protein level were detected by flow cytometry. Quantitative real-time PCR was used to measure the expression of inducible nitric oxide synthase (iNOS), interferon regulatory factor 8 (IRF-8), IL-6 receptor α subunit (IL-6Rα), granulocyte colony-stimulating factor receptor (G-CSFR), CCAAT/enhancer binding protein β (C/EBPβ), suppressor of cytokine signaling 1 (SOCS1) and SOCS3 at mRNA level in G-MDSC. Chromatin immunoprecipitation was performed to detect the acetylation of histone H3 at the promoters of SOCS1 and SOCS3 genes. Plasma concentrations of IL-6 and granulocyte colony-stimulating factor (G-CSF) and protein levels of IL-10, transforming growth factor-β (TGF-β) and nitric oxide (NO) in the culture supernatant of G-MDSC stimulated with LPS were measured by ELISA. Results:(1) Compared with the control group, the proportion of HLA-DR -CD11b + CD33 + CD14 -CD15 + G-MDSC as well as the concentration of ROS and the expression of inhibitory molecules (Arg-1, PD-L1 and CTLA4) in G-MDSC increased significantly in patients with acute KD ( P<0.05). Moreover, the concentrations of IL-10 and TGF-β in culture supernatant of G-MDSC were also higher than those of the control group after stimulation with lipopolysaccharide for 48 h ( P<0.05). All of the seven afore-mentioned indexes in KD patients with coronary artery lesion (CAL group ) were lower than those in patients without coronary artery lesion (NCAL group) ( P<0.05), and restored to some extent after IVIG therapy ( P<0.05). There were no statistical differences in iNOS expression or NO concentration in culture supernatant of G-MDSC among different groups ( P<0.05). (2) Plasma concentrations of IL-6 and G-CSF, and the expression of IL-6Rα, gp130, G-CSFR, pSTAT3 and C/EBPβ increased remarkably during acute phase of KD ( P<0.05). The expression of IRF-8 at transcription level in patients with acute KD was found to be lower than that of healthy controls ( P<0.05), and restored significantly after IVIG therapy ( P<0.05). Moreover, the plasma concentrations of IL-6 and G-CSF and the expression of IL-6Rα, gp130, G-CSFR and IRF-8 in the CAL group were higher than those in the NCAL group ( P<0.05), while the expression of pSTAT3 and C/EBPβ was lower in the CAL group ( P<0.05), which were restored by IVIG therapy ( P<0.05). (3) In patients with acute KD, the expression of SOCS1 and SOCS3 at mRNA level and histone acetylation at the promoters of SOCS1 and SOCS3 genes were reduced significantly in comparison with those in healthy controls ( P<0.05) , but were increased remarkably after IVIG treatment( P<0.05). The four indexes were higher in the CAL group than in the NCAL group ( P<0.05). Pearson correlation analysis showed the expression of SOCS1 and SOCS3 was negatively correlated with the protein level of pSTAT3 in G-MDSC of patients with acute KD ( r=-0.46 and -0.32, P<0.05). Conclusions:Changes in the number and function of G-MDSC caused by aberrant histone acetylation at SOCS1 and SOCS3 genes might contribute to the immune dysfunction and vascular damage in patients with KD.

Objective:To investigate the changes of monocytic myeloid-derived suppressor cells (M-MDSC) in children with acute Kawasaki disease (KD) and its roles in the immunological pathogenesis of KD.Methods:A total of 38 children with acute KD were enrolled in the present study and 32 age-matched healthy children were selected as control group. The proportions of HLA-DR -CD11b + CD33 + CD15 -CD14 + M-MDSC and CD4 + CD25 + CD127 - regulatory T cells (Treg) in peripheral blood, concentrations of reactive oxygen species (ROS) and expression of arginase-1 (Arg-1), CD39, CD73, CD40, CD40L and CCR5 at protein levels were detected by flow cytometry. Quantitative real-time PCR was used to evaluate the transcription levels of inducible nitric oxide synthase (iNOS) in M-MDSC and the transcription levels of cytotoxic T-lymphocyte associated antigen 4 (CTLA4) and lymphocyte-activation gene 3 (LAG3) in Treg. Concentrations of NO, CCL3, CCL4, CCL5, IL-10 and TGF-β in the supernatants of cell culture were measured by ELISA. Results:(1) The proportion of HLA-DR -CD11b + CD33 + CD15 -CD14 + M-MDSC, the concentration of intracellular ROS and the expression of iNOS, CD39 and CD73 in M-MDSC decreased significantly in patients with acute KD as compared with those in the control group ( P<0.05), and the concentrations of NO, IL-10 and TGF-β in culture supernatant of M-MDSC were lower than those in the control group upon lipopolysaccharide (LPS) stimulation for 48 h ( P<0.05). All of the aforementioned indexes restored to some extent after intravenous immunoglobulin (IVIG) therapy ( P<0.05). No statistical differences were found in Arg-1 expression between healthy controls and patients with KD before or after IVIG therapy ( P<0.05). (2) CD40 expression on M-MDSC was significantly lower in the acute KD group than in the control group ( P<0.05). The concentrations of CCL3, CCL4 and CCL5 in the culture supernatants of M-MDSC were lower in the acute KD group than in the control group after LPS stimulation ( P<0.05). With IVIG treatment, all of the indexes were up-regulated significantly ( P<0.05), although CD40 expression was still lower in the acute KD group than in the control group ( P<0.05). (3) The proportion of CD4 + CD25 + CD127 -Treg and the expression of CTLA4, LAG3, CD40L and CCR5 reduced significantly in patients with acute KD as compared those in healthy controls ( P<0.05), and all increased remarkably after IVIG therapy ( P<0.05). Pearson correlation analysis showed a positive correlation between the proportions of M-MDSC and Treg in patients with acute KD ( r=0.58, P<0.05). Conclusions:Insufficiency and impaired function of M-MDSC might be a major cause of immune dysfunction in patients with acute KD.

To scientifically evaluate the intervention effect of Chinese medicine preventive administration(combined use of Huo-xiang Zhengqi Oral Liquid and Jinhao Jiere Granules) on community population in the case of coronavirus disease 2019(COVID-19), a large cohort, prospective, randomized, and parallel-controlled clinical study was conducted. Total 22 065 subjects were included and randomly divided into 2 groups. The non-intervention group was given health guidance only, while the traditional Chinese medicine(TCM) intervention group was given two coordinated TCM in addition to health guidance. The medical instructions were as follows. Huoxiang Zhengqi Oral Liquid: oral before meals, 10 mL/time, 2 times/day, a course of 5 days. Jinhao Jiere Granules: dissolve in boiling water and take after meals, 8 g/time, 2 times/day, a course of 5 days, followed up for 14 days, respectively. The study found that with the intake of medication, the incidence rate of TCM intervention group was basically maintained at a low and continuous stable level(0.01%-0.02%), while the non-intervention group showed an overall trend of continuous growth(0.02%-0.18%) from 3 to 14 days. No suspected or confirmed COVID-19 case occurred in either group. There were 2 cases of colds in the TCM intervention group and 26 cases in the non-intervention group. The incidence of colds in the TCM intervention group was significantly lower(P<0.05) than that in the non-intervention group. In the population of 16-60 years old, the incidence rate of non-intervention and intervention groups were 0.01% and 0.25%, respectively. The difference of colds incidence between the two groups was statistically significant(P<0.05). In the population older than 60 years old, they were 0.04% and 0.21%, respectively. The incidence of colds in the non-intervention group was higher than that in the intervention group, but not reaching statistical difference. The protection rate of TCM for the whole population was 91.8%, especially for the population of age 16-60(95.0%). It was suggested that TCM intervention(combined use of Huoxiang Zhengqi Oral Liquid and Jinhao Jiere Granules) could effectively protect community residents against respiratory diseases, such as colds, which was worthy of promotion in the community. In addition, in terms of safety, the incidence of adverse events and adverse reactions in the TCM intervention group was relatively low, which was basically consistent with the drug instructions.
Adolescent ; Adult ; Betacoronavirus ; Coronavirus Infections ; drug therapy ; Drugs, Chinese Herbal ; Humans ; Medicine, Chinese Traditional ; Middle Aged ; Pandemics ; Pneumonia, Viral ; drug therapy ; Prospective Studies ; Young Adult

Objective To explore the clinical features and genetic characteristics of primary immunodeficiency disease (PIDs) with skin symptoms in children. Methods The clinical data of PIDs with skin symptoms in 15 children from January 2014 to March 2017 were analyzed retrospectively. Results The median age at onset in 15 children was 4 months (neonatal period to 11 years 8 months). All of them showed obvious skin symptoms, including eczema or chilblain rash, pustular psoriasis, skin infections, subcutaneous hemorrhage or skin ecchymosis, ichthyosiform erythroderma, progeroid appearance, or other cutaneous vasculitis. The accompanying manifeslations included recurrent infections, auto inflammation, autoimmunity, growth retardation, or lymphoid proliferation, and impairment of brain, lung, kidney and other important organs. Eosinophil counts were increased in 5 children, IgE levels were elevated in 5 children, and 4 children were abnormal in both indicators. Gene detection showed WAS, RNASEH2C, NLRP12, IL36RN, NRAS, PIK3CD, STAT1, FOXP3, STAT3, DOCK8, TYK2, SPINK5, NBAS or ITGB2 gene mutations, respectively. Two children died from multiple organ dysfunction syndrome, 1 child was lost for follow up, the remaining 12 children survived and were under the individualized treatment. Conclusions A variety of PIDs can have skin symptoms. When accompanied by recurrent infections, auto inflammation, autoimmune, growth retardation, or lymph proliferation, PIDs should be considered, and gene detection is helpful for the diagnosis.

Objective: To investigate the clinical features and genetic characteristics of cases with X-linked immunodeficiency with magnesium defect, Epstein-Barr virus (EBV) infection, and neoplasia (XMEN). Methods: Characteristics of clinical material, immunological data and gene mutation of two cases with XMEN in the same family in China were retrospectively analyzed. The related reports literature were searched by using search terms'MAGT1 gene’or'XMEN’. Results: The proband, a 2-year-eight-month old boy, was admitted due to 'Urine with deepened color for two days and yellow stained skin for one day’. He had suffered from recurrent upper respiratory tract infection and sinusitis previously. Hemoglobin level was 38 g/L. The absolute count of reticulocytes was 223.2×10⁹/L. Urobilinogen level was 38 μmol/L (3-16 μmol/L). Coomb's test was positive. Both total (77.2 μmol/L) and indirect bilirubin (66 μmol/L) levels were elevated. There was an inverted CD4⁺/CD8⁺T cell ratio (0.89). The gene sequencing results showed MAGT1 gene c.472delG, p.D158Mfs*6 mutation. His 1-year-6-month old brother, was also identified to have MAGT1 gene c.472delG, p.D158Mfs*6 mutation.The younger brother mainly suffered from recurrent upper respiratory tract infection, accompanied by an inverted CD4⁺/CD8⁺T cell ratio (0.45), an elevated ratio and number of total B cells (45.7%). A total of 7 reports were retrieved including 11 male cases caused by MAGT1 gene mutation. These 11 cases were characterized by EBV viremia (11 cases), recurrent upper respiratory tract infection, otitis media or sinusitis (10 cases), secondary neoplasia diseases (8 cases), reduction of CD4⁺/CD8⁺ T cell ratio (7 cases),and autoimmune thrombocytopenia or hemolytic anemia (2 cases). Conclusion XMEN often manifests as male onset, recurrent upper respiratory tract infection, otitis media or sinusitis, EBV viremia, lymphoproliferative disease or lymphoma, autoimmune diseases and reduction of CD4⁺/CD8 ⁺T cell ratio. NKG2D expression in NK cells is significantly reduced, and gene sequencing analysis shows a pathogenic mutation in MAGT1 gene.

A method for simultaneous determination of 12 kinds of chlorinated disinfection byproducts (DBPs) in drinking water was developed based on liquid-liquid extraction gas chromatography equipped with electron capture detector (GC/ECD).The procedural standard calibration was adopted to eliminate the interference of different matrix.The method detection limits for 12 DBPs were 0.08-0.21 μg/L and the entire analytical procedure was finished in 21.50 min.The recoveries were in the range of 80.9%-115.7% and the relative standard deviations (RSD) were between 0.9% and 9.9% at different concentration levels (5 and 50 μg/L) in tap water and surface water.The correlation coefficients for all 12 kinds of DBPs were greater than 0.99 in the linearity range of 0.5-200 μg/L.The method was applied to determine DBPs in drinking water and source water.This method was rapid and competent for detection of volatile DBPs in drinking water.

Objective To investigate the changes and significances of inducible IL-35-producing regulatory T cells(iTR35) in immunological pathogcnesis of Kawasaki disease (KD).Methods Forty-eight children with KD and 32 age-matched healthy children (healthy control group) consented to participate in this study.Flow cytometry was performed to evaluate the proportions of CD4+ FOXP3-IL-12p35+IL-27EBI3+iTR35 and CD4+CD25high FOXP3+regulatory T cells (Treg),and expression levels of associated molecules such as programmed death-ligand 1 (PD-L1),CD169,programmed death 1 (PD-1),CD43,IL-12p35,Epstein-Barr virus induced 3 (IL-27EBI3),glycoprotein 130(gp130),IL-12 receptor beta 2 (IL-12Rβ2),phosphated signal transducer and activator of transcription 1 (pSTAT1) and phosphated signal transducer and activator of transcription 4 (pSTAT4).Transcription levels of the Sre homology 2 domain-containing protein tyrosine phosphatase 2 (SHP-2),phosphatase and tensin homolog (PTEN),Vavl guanine nucleotide exchange factor(Vav) in CD4+T cells were determined by quantitative real-time PCR.Plasma concentrations of IL-35,IL-10,TNF-α and IL-12 were measured by enzyme-linked immunosorbent assay.Results (1) The proportions of iTR35 and its expressions of IL-12p35 and IL-27EBI3 in patients with acute KD dccreased remarkably[iTR35:(0.72±0.26) ‰ vs (1.65±0.43) ‰,P＜0.05],and restored after treatment [iTR35:(1.58±0.63) ‰ vs (0.72±0.26) ‰,P＜0.05].(2) The proportions of Treg and transcriptional levels of IL-12p35 and IL-27EBI3 were down-regulated during acute phase of KD [Treg:(3.26±1.21) ％ vs (7.26±2.86) ％,P＜0.05],and increased to some extent after therapy [Treg:(5.89±2.60)％ vs (3.26±1.21)％,P＜0.05].Meanwhile,plasma concentrations of IL-35 and IL-10,and expressions of gp130,IL-12Rβ2,pSTAT1 and pSTAT4 in iTR35 of patients with acute KD were found lower than those of the healthy control group (all P＜0.05),and increased after treatment (P＜0.05).Additionally,positive correlations were found between plasma concentrations of IL-35 and the proportion of iTR35 or its expressions of IL-12p35 and IL-27EBI3,respectively.(3) Expressions of PD-L1 and CD169 on CD14 + cells and plasma concentrations of TNF-α and IL-12 were elevated significantly during acute KD(all P＜0.05),as well as expression levels of the ligands (PD-1 and CD43) and its downstream molecules (SHP-2,PTEN,Vav) in CD4 + T cells were found to be lower in patients with acute KD (P＜0.05),and restored remarkably after therapy.Conclusion Insufficiency of iTR35 and its expression of IL-35 might be one of the important factors contributing to immunological dysfunction in KD.

Objective To investigate the changes and significance of ubiquitination of Foxp3 pro-tein during the acute phage of Kawasaki disease ( KD) .Methods Forty-eight children with KD and twenty-eight age-matched healthy children were recruited in this study.Co-immunoprecipitation and Western blot assays were performed to determine the poly-ubiquitination status of Foxp3 in CD4+T cells.The percentages of CD4+CD25high Foxp3+regulatory T cells ( Treg) and the levels of IL-10, transforming growth factor-β( TGF-β) , cytotoxic T lymphocyte-associated protein-4 ( CTLA4 ) , STIP1 homology and U-Box containing protein 1 (STUB1), heat shock protein 70 (HSP70), ubiquitin-specific-processing protease 7 (USP7) and pSTAT3 were analyzed by flow cytometry analysis.Quantitative real-time PCR was used to evaluate the tran-scription levels of TLR1-10, IL-1R1, IL-1RAP, IL-6Rα, gp130, TNFR1, MyD88 and RIP1 in CD4+T cells.Plasma concentrations of IL-1β, IL-6 and TNF-αwere measured by enzyme-linked immunosorbent as-say.Results (1) The percentages of Treg cells and the levels of IL-10, TGF-β, CTLA4 and forkhead box P3 (Foxp3) in patients with acute KD were lower than those of healthy subjects (P<0.05), while the poly-ubiquitination of Foxp3 protein was significantly enhanced in patients with acute KD [(0.52 ±0.19) vs (0.08±0.02),P<0.05].Meanwhile, the four former items in KD patients with coronary artery lesions (KD-CAL+) were lower than those of KD patients without coronary artery lesions (KD-CAL-) (P<0.05), while the polyubiquitination level of Foxp3 protein in KD-CAL+group was much higher than that of KD-CAL-group [(0.70±0.28) vs (0.43±0.17), P<0.05].The levels of Treg cells, IL-10, TGF-βand CTLA4 in patients with KD were increased and the ubiquitination of Foxp3 protein was inhibited [(0.24±0.10) vs (0.52±0.19), P<0.05] upon the treatment with IVIG.(2) The levels of STUB1 and HSP70 in CD4+T cells were significantly elevated during acute KD, while the levels of USP7 were decreased (P<0.05).The ratios of STUB1/USP7 in patients with acute KD were much higher than those of the control group [(2.65± 0.92) vs (1.09±0.37), P<0.05], but were significantly decreased after IVIG therapy [(1.46±0.53) vs (2.65±0.92), P<0.05].A negative correlation was found between STUB1/USP7 ratio and Foxp3 level during acute KD (r=-0.56, P<0.05).Moreover, KD patients with CAL+showed higher levels of STUB1 and HSP70 and higher ratios of STUB1/USP7 (P<0.05), but lower levels of USP7 as compared with those of KD-CAL-group (P<0.05).(3) The plasma concentrations of inflammatory cytokines (IL-1β, IL-6 and TNF-α), the levels of surface receptors ( IL-1R1/IL-1RAP/TLR4, IL-6Rα/gp130 and TNFR1) and its downstream molecules ( MyD88, pSTAT3 and RIP1) in CD4+T cells were up-regulated during acute KD ( P<0.05), especially in patients with CAL+, but were down-regulated upon the IVIG therapy (P<0.05).No significant differences with other TLRs were found among the groups (P>0.05).Conclusion Hyper-ubiq-uitination of Foxp3 protein might be involved in the immune dysfunction during Kawasaki disease.

OBJECTIVETo analyze the clinical features and mutation of MUT gene in a Chinese patient with isolated methylmalonic acidemia.

METHODSThe clinical characteristics and laboratory tests data were collected. Genomic DNA was extracted from peripheral blood leukocytes. The 13 exons and their flanking sequences of the MUT gene were amplified with polymerase chain reaction and subjected to direct DNA sequencing.

RESULTSThe patient has featured failure to thrive, lethargy, seizure, hypotonia, severe ketoacidosis and hyperammonemia. Tandem mass results showed reduction of multiple acylcarnitine. Urine organic acid testing showed pronounced increase in methylmalonate excretion. Homocysteine was normal. The patient showed no response to vitamin B12 treatment. The above results suggested that the patient had isolated methylmalonic acidemia. DNA sequencing analysis confirmed that the patient has carried two MUT gene mutations, c.755dupA and a novel mutation c.944dupT.

CONCLUSIONInherited metabolic disease screening plays an important role in the diagnosis of clinical diseases. However, to confirm the results will need gene mutation analysis.

Amino Acid Metabolism, Inborn Errors ; enzymology ; genetics ; Base Sequence ; Female ; Humans ; Infant, Newborn ; Methylmalonyl-CoA Mutase ; genetics ; Molecular Sequence Data ; Mutation