Objective To analyze 4 child patients with 3-methylcrotonyl-coenzyme A carboxylase deficiency (MCCD) identified by neonatal screening and confirmed by urine gas chromatography-mass spectrometry (GC/MS) and genetic analysis.Methods Newborns whose C4DC + CSOH concentration was above 0.6 μmol/L in newborn screening were recalled for rescreening,and the CADC + C5OH concentrations in their mothers were detected.The child patients suspected with MCCD were further confirmed by urine GC/MS and genetic analysis.Results Three child patients were definitely diagnosed as MCCD by genetic analysis,including 1 MCCD,1 maternal MCCD and 1 paternal MCCD.The other 1 child patient suspected with MCCD had only one allele in MCCC1.Conclusion The mother and father of newborns with elevated C4DC + C5OH identified in neonatal screening should routinely perform MS / MS testing.When only one pathogenic locus is found in the suspected MCCD child patients by genetic analysis,they should be followed up regularly.

Objective:To investigate the effect of miR-424-5p on radiosensitivity and its mechanism in cervical cancer patients.Methods:The expression levels of miR-424-5p in the cervical cancer tissues and Hela cells were detected by RT-qPCR. The apoptosis rate of Hela cells was determined by flow cytometry. The proliferation activity of Hela cells was detected by CCK-8 assay. The protein expression levels in Hela cells were measured by Western blot.Results:Compared with normal tissues and cells, the expression level of miR-424-5p was significantly down-regulated in the cervical cancer tissues and Hela cells (1.03 vs. 0.88, P<0.01; 1.00 vs. 0.75, P<0.01). Overexpression of miR-424-5p significantly inhibited the proliferation activity of Hela cells after radiation treatment ( P<0.01), and significantly increased the apoptosis rate of Hela cells after radiation treatment (24.82% vs. 49.94%, P<0.001). Overexpression of miR-424-5p inhibited HMGA1 expression (1.01 vs. 0.63, P<0.01). miR-424-5p directly affected HMGA1, thereby impacting the radiosensitivity of cervical cancer radiotherapy. Conclusion:miR-424-5p can improve the radiosensitivity of cervical cancer radiotherapy by directly targeting HMGA1.

Objective To explore the clinical feature and gene types in patients with primary carnitine deficiency. MethodsClinical data of 6 patients with primary carnitine deficiency and 2 patients with maternal carnitine deficiency found in the screening by tandem mass spectrometry technology during December 2013 to December 2016 were retrospectively analyzed. Results The free carnitine levels of 8 patients in initial and recall screening were 5.85±1.65 μmol/L and 5.22±1.02 μmol/L. Two pathogenic alleles were detected in each patient with primary carnitine deficiency by genetic and metabolic disease panel based on Ion Torrent semiconductor sequencing. After treatment with oral L-carnitine, the free carnitine levels of 6 patients with primary carnitine deficiency were 20.24±3.88 μmol/L. The carnitine levels returned to normal after mixed feeding for one week in 2 patients with maternal carnitine deficiency, and no genetic diagnosis was carried out. Conclusion Primary carnitine deficiency can be effectively detected using tandem mass spectrometry technology and next generation sequencing panel and the prognosis is good with early standard treatment.

Objective To investigate clinical manifestations,histopathological features and treatment of ulcerative colitis (UC) complicated by pyoderma gangrenosum (PG).Methods Data on clinical manifestations,auxiliary examination findings,treatment and prognosis were collected from 8 inpatients with UC complicated by PG in Peking Union Medical College Hospital between July 2009 and July 2016,and analyzed retrospectively.Results Of the 8 cases,5 were male,and 3 were female.Theaverage age of onset was 30.6 years and 35.1 years in males and females respectively.All the patients developed intestinal symptoms of UC before the onset of PG with an average time interval of 5 years.Moreover,all the patients had active total colonic type UC at the onset of PG,including 6 with moderately active UC and 2 with mildly active UC.PG manifested as painful ulcers in 8 patients,and affected lower limbs in 7 patients.Histopathological examination of skin lesions showed typical characteristics of vasculitis in 5 patients.Five patients were complicated by arthralgia.All the patients were treated with glucocorticoids and 5-aminosalicylic acid agents as the basic therapy,3 patients received extra treatment with immunosuppressive agents or minocycline,and 2 with infliximab.Conclusions PG is a severe skin manifestation of UC,commonly occurs in patients with total colonic type UC in the active stage,and mostly affects the lower limbs,with typical histopathological features of vasculitis.

Objective To explore the diagnostic significance of CT and MRI in dermatofibrosarcoma protuberans.Methods Analyze the CT and MRI images of 16 cases which were confirmed as dermatofibrosarcoma protuberans by pathology.The medical imaging features of dermatofibrosarcoma protuberans were summarized.In the total 16 cases(including 6 male cases,10 female cases),15 cases had suffered from dermatofibrosarcoma protuberans for more than 1 year, 11 cases for more than 5 years, and 9 cases had history of recurrence.Results On MRI, the mass was slightly hypointense on T 1 WI, inhomogeneously hyperintense on T 2 WI with inhomogenous enhancement.The diameters of mass were less than 5 cm in 3 cases,and were more than 5cm in 13 cases.Fifteen cases had clear demarcation between the masses and their adjacent muscles , 7 cases had “suspension sign” in shapes, 10 cases had “sub-nodules outward” features at the edge of the tumors , 12 cases had “multinodular” features inside the tumor , and 8 tumors grew into the surrounding fat layer like roots.Conclusion Dermatofibrosarcoma protuberans can be diagnosed accurately based on the features displayed on CT and MRI.

Objective To determine the reference values of 11 amino acids measured by non-derivatized tandem mass spectrometry ( MS/MS).Methods 22 430 healthy newborns and 14 children with metabolic dysfunction in Nanjing were enrolled in this study.The levels of the 11 amino acids, including Ala, Arg, Cit, Gly, Leu +Ile, Met, Orn, Phe, Pro, Tyr and Val, were measured by non-derivatized tandem mass spectrometry using dry blood spots.After pre-setting up different cutoff values according to the amino acid levels of the newborns, reference value ranges of the 11 amino acids were determined by using the method of percentile combined with ROC curves.Results According to the results of frequency distribution histogram, the levels of the 11 amino acids of newborns belong to approximate normal distribution.By analysis of ROC curves, the cut-off values for amino acids were 0.2%-99.8%.Conclusion It established reference values of 11 amino acids in newborn and provided basis for the other screening center to make the cut-off value.

Objective: To explore an efficient method for the establishment of 3D finite element model based on CBCT images. Methods: Mandible of a male volunteer was scanned by CBCT, and the resulting DICOM data was used for 3D reconstruction in Mimics17 software. Then with the. stl format file, the result of 3D reconstruction was imported into Geomagic Warp 2015, in which 3D models consisting of triangular patches for dentition, periodontal ligament and alveolar bone were created. With free meshing algorithm, the 3D finite element model of mandible with full dentition consisting of 10-node tetrahedron elements was obtained under the constraint that the maximum inner angle was set to be 25°. Results: The 3D finite element model for human mandible with full dentition was established. The total number of nodes is 299286, the elements number for dentition, periodontal ligament and alveolar bone are105805, 122427 and 577529, respectively. Conclusion: The proposed method can be used for the establishment of 3D finite element model of mandible with full dentition based on CBCT images, and it has the merits of good stability, high precision and wide application compared with the traditional modeling method.

Objective:To investigate the clinical characteristics and pathogenic mutations of propionic acidemia.Methods:Clinical data of two patients with propionic acidemia admitted to the Obstetrics and Gynecology Hospital of Nanjing Medical University from May 2017 to June 2018 were collected. Genomic DNA was extracted from the peripheral blood of the patients and their parents. Inherited disease panel based on Ion Torrent semiconductor sequencing technology was performed to detect gene mutations, and those with suspected pathogenic mutations were verified by Sanger sequencing. Descriptive statistical analysis was used for data analysis.Results:Case 1 was suspected of sepsis and admitted to the Obstetrics and Gynecology Hospital of Nanjing Medical University due to "drowsiness and milk rejection" on the second day after birth. Tandem mass spectrometry suggested the level of propionyl carnitine and its ratios to acetylcarnitine and free carnitine were increased. Urine gas chromatography-mass spectrometry showed elevated 3-hydroxypropionic acid and methylcitric acid. Genetic analysis revealed that the infant carried c.331C>T (p.R111X)/c.1228C>T (p.R410W) compound heterozygous mutations in the PCCB gene. The infant was diagnosed with propionic acidemia and treated with a special diet with an L-Carnitine supplement but died of sudden coma and vomiting without precipitating factors at three months of age. Case 2 presented with sudden vomiting, drowsiness, and anergia on the admission at five-months old. Tandem mass spectrometry showed increased propionyl carnitine level and its ratios. Compound heterozygous mutations of c.146delG (p.G49EfsX16)/c.1253C>T (p.A418V) in the PCCB gene were identified in the patient, of which c.146delG (p.G49EfsX16) was a de novo mutation and was evaluated as a pathogenic mutation. The patient was on a special diet with an L-Carnitine supplement, but with disobedience. Followed up to the age of three years and eight months, the child was severely underdeveloped. Conclusions:Neonates with clinically suspected sepsis may have propionic acidemia, and tandem mass spectrometry and genetic testing should be performed as soon as possible to confirm or rule out the diagnosis. Further investigations on the pathogenesis and function of the new mutation are still needed.

OBJECTIVETo detect potential mutations of MAT1A gene in a child suspected with simple hypermethioninemia by MS/MS neonatal screening.

METHODSClinical data of the child was collected. Genomic DNA was extracted by a standard method and subjected to targeted sequencing using an Ion AmpliseqInherited Disease Panel. Detected mutations were verified by Sanger sequencing.

RESULTSThe child showed no clinical features except evaluated methionine. A novel compound mutation of the MAT1A gene, i.e., c.345delA and c.529C>T, was identified in the child. His father and mother were found to be heterozygous for the c.345delA mutation and c.529C>T mutation, respectively.

CONCLUSIONThe compound mutation c.345delA and c.529C>T of the MAT1A gene probably underlie the disease in the child. The semi-conductor sequencing has provided an important means for the diagnosis of hereditary diseases.

Amino Acid Metabolism, Inborn Errors ; genetics ; pathology ; Base Sequence ; DNA Mutational Analysis ; methods ; Family Health ; Fathers ; Female ; Genetic Predisposition to Disease ; genetics ; Glycine N-Methyltransferase ; deficiency ; genetics ; Heterozygote ; Humans ; Infant, Newborn ; Infant, Newborn, Diseases ; genetics ; pathology ; Male ; Methionine Adenosyltransferase ; genetics ; Mothers ; Mutation

Objective To investigate the combined application value of tandem mass spectrometry ( MS/MS) and high performance liquid chromatogram-tandem mass spectrometry ( LC-MS/MS ) in the newborn screening of children with methylmalonic acidemia ( MMA ) . Methods The dried blood spot samples from the newborn with abnormal propionylcarnitine ( C3) or C3/acetylcarnitine ( C2) or C3/free carnitine ( C0) levels in the preliminary screening of MS/MS were collected, and the concentrations of MMA, methylcitric acid ( MCA) and homocysteine ( Hcy) in these samples were detected with LC-MS/MS. The neonates with increased MMA, MCA or Hcy levels were recalled, and their urinary organic acids were analyzed with gas chromatographic mass spectrometry (GC/MS). Last, gene mutation anal-ysis was performed to make a definite diagnosis.Results A total of 423 samples with abnormal C3 or C3/C2 or C3/C0 levels in the new-born screening were collected, and the positive rate of preliminary screening was about 1％. The LC-MS/MS results showed that 8 neo-nates had higher MMA and tHcy levels. The GC/MS results further showed that the level of MMA increased slightly. Conclusion The combined application of MS/MS and LC-MS/MS may increase the positive predictive value and decrease the false positive rate of MMA screening in the newborn, which may have an important clinical significane in the screening of inherited metabolic disorders.