Objective To explore the characteristics and ecological risk assessment of heavy metals pollution in the fluvial sediment in Hengyang section of Xiang river.Methods The fluvial sediments in 18 sites in 10 sections of Hengyang section of Xiang river were collected for determination of heavy metals(Cu,Zn,As,Hg,Cd,Cr,Pb) in 2007.The accumulation levels of heavy metals in the fluvial sediment and their potential ecological risks were assessed by the Hankanson potential ecological risk(PER) factors method.Results The average potential ecological risk index of Cd in sediment of Xiang river was 352.1 with the highest ecological risk,the index of Hg was 272.1 with higher ecological risk,the index of Pb and As was 150.1 and 104.7 with high ecological risk,the index of Cr,Zn and Cu were all lower than 40 with low ecological risk.On the whole,the integrated pollution index of seven kinds of heavy metal was 913.4.Conclusion The fluvial sediment of Hengyang section of Xiang rive has been polluted by heavy metals in a certain degree and is characterized as a complex pollution situation with a higher ecological risk.

ObjectiveTo evaluate the efficacy of stereotactic body radiotherapy combined with coinstan taneous gemcitabine,and gemcitabine alone for advanced pancreatic cancer.Methods56 advanced pancreatic cancer patients were assigned into observation group,which accepted stereotactic body radiotherapy combined with coinstantaneous gemcitabine 500 mg/m2,d1,d8.Other 50 patients were assigned into the control group which only accepted gemcitabine 1 000 mg/m2,d1,d8,d15.Stereotactic body radiotherapy was delivered with a total dose of 4 000-4 500 cGy in 10 fractions.ResultsCT examinations were carried out 2 months after treatment.The response rate of the observation group and control group was 82％ and 16％ respectively,and the pain relief rate was 67％ and 17％ respectively.The time to progression of the observation group was 14 months,and was better than that of the control group(7.5 months,x2 =7.31,P =0.032).The median survival time of the observation group and control group was 15.8 months and 13.2 months,and the difference had no statistical significance(x2 =3.28,P =0.082).ConcolusionStereotactic body radiotherapy combined with gemcitabine has a better overall response rate and a pain relief rate.It can prolong the time to progression,but can't improve the overall survival.

Objective: To reveal the molecular epidemiologic characteristics of glucose-6-phosphate dehydrogenase (G6PD) gene and to evaluate based on the genetic analysis the newborn screening program performance and enzymatic diagnosis of G6PD deficiency in Guangzhou. Methods: G6PD enzyme activities were measured by quantitative fluorescence assay in dry blood spots of 16 319 newborns(8 725 males, 7 594 females) 3-7 days after birth in Guangzhou Newborn Center. They were born in Guangzhou form Oct. 1 to 20, 2016. The cutoff value of G6PD was less than 2.6 U/g Hb in dry blood spots. G6PD deficiency was diagnosed when G6PD<1 700 U/L or G6PD/6PGD<1 in red blood cells. Genetic analysis of G6PD gene was performed on the dry blood spot samples of 823 newborns (including positive 346, negative 477)with various levels of G6PD enzyme activities through fluorescence PCR melting curve analysis(FMCA) to detect 15 kinds of mutations reported to be common among Chinese.G6PD gene Sanger sequency was performed in seven highly suspicious patients with negative results by FMCA. Results: (1) Using the cutoff value of G6PD< 2.6 U/g Hb , a total of 687(4.2%) newborns showed positive screening results, including 560 (6.4%) males and 127(1.7%) females. (2) Among the newborns with positive screening results, 214 males and 122 females were randomly chosen for G6PD gene analysis. The results showed that 197 (92.1%) males were hemizygote and 108(88.6%) females were mutation carriers with one to four alleles. Among the newborns with negative screening results, 41 males with G6PD 2.6-2.8 U/g Hb and 436 females with G6PD 2.6-4.5 U/g Hb were chosen for genetic analysis.Mutations were detected in 5(12.2%)boys, and 226(51.8%) girls were carriers.G6PD gene Sanger sequency of seven highly suspicious patients showed that c.406C>T, c.551C>T, c.835A>T hemizygote were found in 3 male's samples, respectively. (3) The estimated prevalence of harboring mutation was 6.0% in males and 13.5% in females according to rates of mutation in samples with various levels of G6PD enzyme activities. Six common mutations were c.1388G>A、c.1376G>T, c.95A> G, c.871G>A, c.1024C>T, c.392G>T, accounting for 95.5% of detected alleles .(4) based on results of G6PD gene analysis, the newborn scereening of G6PD deficiency with cutoff value G6PD<2.6 U/g Hb yielded a positive predict value(PPV) of 93.5%, a false-positive rate of 0.5%, and a sensitivity of 99.0% for males. A PPV of 88.5%, a false-positive rate of 0.2% . The prevalence of severe type G6PD deficiency in females was about 1.5%. Compared with to genetic analysis, the sensitivity and PPV of G6PD activity assay in red blood cells were 95.5%, 97.2%, respectively. Conclusions The prevalence of G6PD deficiency in males was 6.0% in Guangzhou. Six mutations c.1388G>A, c.1376G>T, c.95A>G, c.871G>A, c.1024C>T, c.392G>T accounted for 95.5%. The cutoff value of G6PD<2.6 U/g Hb innewborn screening program and the criteria of biochemical diagnosis could accurately identify G6PD deficiency . Combined with biochemical and molecular analysis will improve the accuracy of diagnosis of G6PD deficiency and detect more heterozygous females.

Objective: To investigate prospectively molecular and clinical characteristics of infants with congenital hypothyroidism (CH) caused by DUOX2 mutations in Guangzhou. Methods: A population-based cohort of 83 patients with CH were recruited based on newborn screening results among 108 899 newborns who were born in Guangzhou between April 1 and September 30 in 2015.Genetic analysis of DUOX2 hotspots(including 11 exons)by PCR-direct sequencing was performed in 52 patients with suspected thyroid dyshormonogenesis (SDH) according to thyroid ultrasound at diagnosis.All the patients were followed up for 3 years.The data of this cohort study(prevalence of CH, detection rate of DUOX2, clinical features) were compared with those of 96 patients with SDH in 2011-2012. Results: (1) The incidence of CH in 2015 was 1∶1 312, and 73.5%(61/83 cases) of CH patients were classified as SDH.Compared with those founded in 2011-2012, the incidence of CH was increased (1∶1 312 vs.1∶2 779), and the difference was significant (P<0.001), while the frequency of SDH was not different significantly (73.5%vs.76.6%, P=0.593). (2)There were 27 cases(51.9%) with SDH detected DUOX2 hotspots variants, including 6 cases with biallelic variants, 21 cases with monoallelic variants, and 1 possible new pathogenic variant p. S1091F.The p. K530X was the most common mutation accounting for 51.5%(17/33 cases) detected allelic and involving in 16 cases (30.8%) with SDH.Novel p. S1091F variant was probably damaging variant.Both detected rate and spectrum of DUOX2 variant were not significantly different compared with those in 2011-2012 (all P>0.05). (3) There were no significant differences in the levels of thyrotropin (bsTSH), serum TSH (sTSH), free thyroxine (FT4) and thyroglobulin in neonates with dry blood spot at diagnosis between children with DUOX2 and without DUOX2 variants cases(all P>0.05). Among 27 cases, 24(88.9%) patients with DUOX2 mutation were transient CH, and 3 cases were permanent CH. Conclusions The incidence of CH was increased in last few years in Guangzhou.Most of them were SDH, and 51.9% of SDH cases had DUOX2 hotspots variants.Temporary CH is the main clinical outcome.The p. K530X was the most common mutation in this cohort population.

Objective:To investigate the sensitivity of newborn screening for neonatal intrahepatic cholestasis caused by Citrin deficiency (NICCD) based on tandem mass spectrometry and the carrying rate of known pathogenic variants of SLC25A13 in Guangzhou population. Methods:A total of 124 250 neonates born in Guangzhou from January 1, 2015 to December 31, 2018 were performed newborn screening for NICCD by tandem mass spectrometry technology. SLC25 A13 gene mutation analysis was performed to diagnose patients with suspected NICCD.The carrying rate of known pathogenic variants of the SLC25 A13 gene in the whole exon sequencing results of 2 395 healthy children in Guangzhou was retrospective analyzed. Results:Among the 124 250 screened neonates, 31 cases were screened positive for NICCD and one of them was confirmed.Three false negative patients with NICCD were found in this cohort.NICCD screening sensitivity was 25%(1/4 cases). All of the four patients were homozygous for c. 851_854del of SLC25A13.Among 2 395 controls, 60 cases were detected heterozygous variant of SLC25A13, including 8 kinds of reported pathogenic variants.The carrying rate of pathogenic alleles was 1/40 (60/2 395 cases). The estimated prevalence of citrin deficiency was about 1/6 400.The most common variant was c. 851_854del (56.7%, 34/60 cases), and the second was c. 790G>A (23.3%, 14/60 cases). The controversial variant c. 2T>C was detected in 113 children with heterozygous and 2 cases with homozygous and the carrying rate of c. 2T>C was 1/20(117/2 395 cases). Conclusions:The carrying rate of pathogenic variants of SLC25A13 and the estimated prevalence of Citrin deficiency in Guangzhou population are high.The sensitivity of newborn screening for NICCD by tandem mass spectrometry is limited.Even if the negative results for screening of multiple genetic and metabolic diseases by tandem mass spectrometry, it is recommended to recheck blood for newborns or infants with delayed jaundice to avoid missed diagnosis.

Objective To evaluate the sensitivity and specificity of enzyme assays,and to provide disease spectrum of lysosomal storage diseases (LSDs).Methods Three thousand three hundred and sixty-four high risk individuals were screened for 24 LSDs at Guangzhou Women and Children's Medical Center between January 2009 and December 2016.Twenty-two kinds of enzyme activities from peripheral blood leucocytes or plasma were measured by using the fluorometry or colorimetry of corresponding artificial substrates,screening for 24 LSDs diseases.Measurement data were represented by (x) ± s,and count data were expressed as a percentage or composition ratio.Results A total of 283 subjects were diagnosed with 18 different kinds of LSDs,and the positive rate of high-risk screening was 8.4％.Among the identified patients,172 cases (60.8％) were mucopolysaccharidosis (MPS),79 cases (27.9％) were sphingolipidoses,18 cases (6.4％) were Pompe diseases,10 cases (3.5％) were affected with mucolipidoses,3 cases (1.1％) were glycoprotein storage diseases,and 1 case(0.4％) was Wolman disease.Of the MPS cases,there were 75 cases of MPS Ⅱ (43.6％),45 cases of MP5 ⅣA (26.2％),24 cases of MPS Ⅵ (14.0％) and 20 cases of MPS Ⅰ (11.6％).Gaucher disease (23/79 cases,29.1％) and metachromatic leukodystrophy (MLD) (21/79 cases,26.6％) were common in sphingolipidoses group.Both the sensitivity and specificity of enzyme assays on peripheral blood leucocytes for LSDs were 100％.Conclusions The most common kinds of LSDs are MPS Ⅱ,MPS Ⅳ A,MPS Ⅵ,Gaucher disease,MLD and Pompe disease.Leukocyte enzymology analysis of high-risk screening LSDs has high sensitivity and specificity.

Objective: To investigate the profiles of blood amino acid and acylcarnitine in early neonates with neonatal intrahepatic cholestasis caused by citrin deficiency (NICCD) and the sensitivity of newborn screening, and to explore potential biochemical metabolic markers for newborn screening program. Methods: Amino acid and acylcarnitine profiles in dried blood spots of newborn screening program were analyzed by tandem mass spectrometry (MS/MS). A total of 158 651 neonates born in Guangzhou from January 1, 2015 to June 30, 2019 were enrolled in this newborn screening program, and additionally 55 patients with NICCD confirmed by SLC25A13 gene analysis in Guangzhou Women and Children Medical Center were included in this study. NICCD screen-positive was defined as the cutoff value of citrulline (Cit) ≥ 30 μmol/L. The values of blood sampling time of the true positive group and those of the false negative group were compared by t-test. The levels of amino acid and acylcarnitine among different groups, including true positive group (Cit≥30 μmol/L), false negative group (Cit 21-<30 μmol/L and Cit<21 μmol/L) and the normal control group, were analyzed by F test, respectively. Results: Among 158 651 neonates, 39 neonates were positive for NICCD screening. Three of them were confirmed NICCD and 4 cases were found to be false negatives. The positive predictive value was 7.7% and the sensitivity was about 43.0%. Among 55 patients with NICCD, 18 cases (18/55, 32.7%) were true positives and 37 cases (37/55, 67.3%) were false negatives based on the cutoff value of citrulline in the dried blood spots for newborn screening. The blood sampling time was significantly different between true positive group and false negative group ((4.28±1.6) vs. (2.98±0.74) d, t=4.06, P<0.01). The increased levels of tyrosine((176.0±98.4) μmol/L), methionine ((37.0±26.9) μmol/L) and phenylalanine ((133.0±80.9)μmol/L) in Cit≥30 μmol/L group (n=18) were significantly different as compared with those in the other three groups, respectively (F=117.0, 58.5, 135.0, P<0.01). The levels of arginine ( (10.0±9.2) , (11.0±9.3) , (9.0±17.8) μmol/L), valine ( (119.0±29.8) , (107.6±14.1) , (102±68) μmol/L) and leucine ( (167.0±37.1) , (161.0±37.7) , (163.5±180.6) μmol/L) were not statistically significant among groups of Cit≥30 μmol/L(n=18), Cit21-<30 μmol/L(n=7) and Cit<21μmol/L(n=30,P>0.05), but they were significantly higher than those of the normal control group ((4±3), (78±21), (114.0±31.5) μmol/L, n=1 000), respectively(F=30.1, 23.0, 29.8, P<0.01). Alanine (Ala) ( (150±50) , (156.0±30.2), (168±105), (152±52) μmol/L) levels showed no significant difference (F=0.86, P>0.05) but the ratios of Ala/Cit (1.52±1.44, 6.82±1.56, 12.06±7.71, 19.42±6.27) decreased significantly among the four groups (F=69.0, P<0.05). The acylcarnitine levels showed no statistically significant results among the different groups (P>0.05). With Cit≥30 μmol/L and Ala/Cit<7.5 as cutoff values, the number of screen-positive cases reduced from 39 to 22 cases with no additional false negative case. With Cit≥21 μmol/L and Ala/Cit<7.5 as cutoff values the number of screen-positive cases increased to 117 cases with 1 additional true positive. Conclusions The profiles of blood amino acid in early neonates with NICCD present the increased levels of multiple amino acids including citrulline, tyrosine, methionine and phenylalanine, and decreased ratio of Ala/Cit. Taking citrulline and ratio of Ala/Cit as screening markers can improve the positive predictive value appropriately. The limited sensitivity of NICCD newborn screening may be related to early blood sampling time.

Objective: To explore the application value of 3.0 T MultiVane XD (MVXD) technique in female patients with uterine adenomyosis and fibroids. Methods: Patients diagnosed with uterine fibroids with ultrasound and suspected of adenomyosis were involved prospectively from March to May 2018, 3.0 T pelvic MRI examinations were performed during peri-ovulatory period. Axialconventional turbo spin echo (TSE) T₂WI, axial MVXD T₂WI, sagittal conventional TSE T₂WI and MVXD sagittal T₂WI were acquired. Two observers rated those 4 series in the aspects of sharpness of uterine border, motion artifacts, identification capability of lesions, confidence of diagnosis and overall image quality. Cohen Kappa analysis was used to evaluate the consistency of scores between 2 observers. Scores of TSE T₂WI and MVXD T₂WI qualities were compared using Wilcoxon matched-pairs signed-ranks test. Results: Twenty patients were enrolled. Axial conventional TSE T₂WI, axial MVXD T₂WI were aquired on all of them. Sagittal conventional TSE T₂WI, sagittal MVXD T₂WI were aquired on 19 among them. Nine patients had only obvious adenomyosis, 6 had only uterinefibroids, and 5 had adenomyosis and uterine fibroids. Compared to conventional TSE technique, scores of two observers in the sharpness of uterine border, motion artifacts, and overall image quality is higher by MVXD with significant difference (P<0.05). The Kappa values for image quality scores of two observers ranged from 0.615 to 0.971, the agreement was good or very good. Conclusion Applying MVXD T₂WI technique to patients with uterine fibroids and adenomyosiscould improve image quality, without sacrificing the ability to recognize and diagnose lesions, compared to conventional TSE T₂WI technique.