Association Analysis of Gene Sequencing by NeoSeq Combined with Tandem Mass Spectrum and Four Neonatal Diseases

BACKGROUND

NeoSeq is a new method of gene sequencing for newborn screening. The goal is to explore the relationship between gene sequencing by NeoSeq combined with tandem mass spectrum (TMS) and four neonatal diseases.

METHODS

A total of 1,989 newborns from August 2010 to December 2021 were enrolled. The case number of congenital hypothyroidism, phenylketonuria, adrenocortical hyperplasia, and glucose-6-phosphate dehydrogenase deficiency was counted, and the results of gene sequencing by NeoSeq and TMS were analyzed.

RESULTS

The proportion of male newborns was higher than that of female newborns (51.68% vs. 48.32%). The detection rate of glucose-6-phosphate dehydrogenase deficiency was higher than that of the other three diseases (0.60% vs. 0.05%, 0.05%, 0.15%). A total of 121 newborns were recalled from 1989 newborns by traditional screening technique, and TMS detected phenylketonuria, citrullinemia, glutaric acidemia type I, and 3-methylcro-tonyl-CoA carboxylase deficiency in 1 newborn each. Gene sequencing by NeoSeq of newborns with positive TMS results confirmed the presence of susceptibility genes, and 17 of 1,868 newborns with normal biochemical tests had pathogenic genes.

CONCLUSIONS

The incidence of glucose-6-phosphate dehydrogenase deficiency is relatively higher in four neonatal diseases, and the detection rate of gene sequencing by NeoSeq combined with TMS is high.

A multicenter prospective study of next-generation sequencing-based newborn screening for monogenic genetic diseases in China

BACKGROUND

Newborn screening (NBS) is an important and successful public health program that helps improve the long-term clinical outcomes of newborns by providing early diagnosis and treatment of certain inborn diseases. The development of next-generation sequencing (NGS) technology provides new opportunities to expand current newborn screening methodologies.

METHODS

We designed a a newborn genetic screening (NBGS) panel targeting 135 genes associated with 75 inborn disorders by multiplex PCR combined with NGS. With this panel, a large-scale, multicenter, prospective multidisease analysis was conducted on dried blood spot (DBS) profiles from 21,442 neonates nationwide.

RESULTS

We presented the positive detection rate and carrier frequency of diseases and related variants in different regions; and 168 (0.78%) positive cases were detected. Glucose-6-Phosphate Dehydrogenase deficiency (G6PDD) and phenylketonuria (PKU) had higher prevalence rates, which were significantly different in different regions. The positive detection of G6PD variants was quite common in south China, whereas PAH variants were most commonly identified in north China. In addition, NBGS identified 3 cases with DUOX2 variants and one with SLC25A13 variants, which were normal in conventional NBS, but were confirmed later as abnormal in repeated biochemical testing after recall. Eighty percent of high-frequency gene carriers and 60% of high-frequency variant carriers had obvious regional differences. On the premise that there was no significant difference in birth weight and gestational age, the biochemical indicators of SLC22A5 c.1400C > G and ACADSB c.1165A > G carriers were significantly different from those of non-carriers.

CONCLUSIONS

We demonstrated that NBGS is an effective strategy to identify neonates affected with treatable diseases as a supplement to current NBS methods. Our data also showed that the prevalence of diseases has significant regional characteristics, which provides a theoretical basis for screening diseases in different regions.

Novel ACADVL variants resulting in mitochondrial defects in long-chain acyl-CoA dehydrogenase deficiency

The pathogenesis of very-long-chain acyl-CoA dehydrogenase (VLCAD) deficiency is highly heterogeneous and still unclear. Additional novel variants have been recently detected in the population. The molecular and cellular effects of these previously unreported variants are still poorly understood and require further characterization. To address this problem, we have evaluated the various functions and biochemical consequences of six novel missense variants that lead to mild VLCAD deficiency. Marked deficiencies in fatty acid oxidation (FAO) and other mitochondrial defects were observed in cells carrying one of these six variants (c.541C>T, c.863T>G, c.895A>G, c.1238T>C, c.1276G>A, and c.1505T>A), including reductions in mitochondrial respiratory-chain function and adenosine triphosphate (ATP) production, and increased levels of mitochondrial reactive oxygen species (ROS). Intriguingly, higher apoptosis levels were found in cells carrying the mutant VLCAD under glucose-limited stress. Moreover, the stability of the mutant homodimer was disturbed, and major conformational changes in each mutant VLCAD structure were predicted by molecular dynamics (MD) simulation. The data presented here may provide valuable information for improving management of diagnosis and treatment of VLCAD deficiency and for a better understanding of the general molecular bases of disease variability.

Serine Metabolism Controls Dental Pulp Stem Cell Aging by Regulating the DNA Methylation of p16

To investigate the characteristics and molecular events of dental pulp stem cells (DPSCs) for tissue regeneration with aging, we isolated and analyzed the stem cells from human exfoliated deciduous teeth (SHED) and permanent teeth of young (Y-DPSCs) and old (A-DPSCs) adults. Results showed that the stemness and osteogenic differentiation capacity of DPSCs decreased with aging. The RNA sequencing results showed that glycine, serine, and threonine metabolism was one of the most enriched gene clusters among SHED, Y-DPSCs, and A-DPSCs, according to analysis based on the Kyoto Encyclopedia of Genes and Genomes. The expression of serine metabolism-related enzymes phosphoserine aminotransferase 1 (PSAT1) and phosphoglycerate (PHGDH) decreased in A-DPSCs and provided less methyl donor S-adenosylmethionine (SAM) for DNA methylation, leading to the hypomethylation of the senescence marker p16 (CDNK2A). Furthermore, the proliferation and differentiation capacity of Y-DPSCs and SHED decreased after PHGDH siRNA treatment, which reduced the level of SAM. Convincingly, the ratios of PSAT1-, PHGDH-, or proliferating cell nuclear antigen-positive cells in the dental pulp of old permanent teeth were less than those in the dental pulp of deciduous teeth and young permanent teeth. In summary, the stemness and differentiation capacity of DPSCs decreased with aging. The decreased serine metabolism in A-DPSCs upregulated the expression of p16 via attenuating its DNA methylation, resulting in DPSC aging. Our finding indicated that serine metabolism and 1 carbon unit participated in stem cell aging, which provided new direction for stem cell aging study and intervention.

DPSCs Attenuate Experimental Progressive TMJ Arthritis by Inhibiting the STAT1 Pathway

Severe inflammation, progressive cartilage, and bone destruction are typical pathologic changes in temporomandibular joint (TMJ) arthritis and lead to great difficulty for treatment. However, current therapy is inefficient to improve degenerative changes in progressive TMJ arthritis. This study investigated the therapeutic effects of human dental pulp stem cells (DPSCs) on severe inflammatory TMJ diseases. Progressive TMJ arthritis in rats was induced by intra-articular injection of complete Freund's adjuvant and monosodium iodoacetate. DPSCs were injected into the articular cavity to treat rat TMJ arthritis, with normal saline injection as control. Measurement of head withdrawal threshold, micro-computed tomography scanning, and histologic staining were applied to evaluate the severity of TMJ arthritis. Results showed that local injection of DPSCs in rats with TMJ arthritis relieved hyperalgesia and synovial inflammation, attenuated cartilage matrix degradation, and induced bone regeneration. Inflammatory factors TNF-α and IFN-γ were elevated in progressive TMJ arthritis and partially decreased by local injection of DPSCs. MMP3 and MMP13 were elevated in the arthritis + normal saline group and decreased in the arthritis + DPSCs group, which indicated amelioration of matrix degradation. The isolated primary synoviocytes were cocultured with DPSCs after inflammatory factors stimulated to explore the possible biological mechanisms. The expression of MMP3 and MMP13 in synoviocytes was elevated after TNF-α and IFN-γ stimulation and partially reversed by DPSC treatment in the in vitro study. The signal transducer and activator of transcription 1 (STAT1) was activated by inflammatory stimulation and suppressed by DPSC coculture. The upregulation of MMP3 and MMP13 triggered by inflammation was blocked by STAT1-specific inhibitor, suggesting that STAT1 regulated the expression of MMP3 and MMP13. In conclusion, this study demonstrated the possible therapeutic effects of local injection of DPSCs on progressive TMJ arthritis by inhibiting the expression of MMP3 and MMP13 through the STAT1 pathway.

[Medium-chain acyl-CoA dehydrogenase deficiency: neonatal screening and follow-uP]

OBJECTIVE

To investigate the epidemiological characteristics, phenotype, genotype, and prognosis of medium-chain acyl-CoA dehydrogenase deficiency (MCADD) in the Chinese population.

METHODS

A retrospective analysis was performed for the clinical data of the neonates who underwent screening with high-performance liquid chromatography-tandem mass spectrometry from January 2009 to June 2018 and were diagnosed with MCADD by gene detection.

RESULTS

A total of 2 674 835 neonates underwent neonatal screening, among whom 12 were diagnosed with MCADD. Gene detection was performed for 10 neonates with MCADD and found 13 mutation types at 16 mutation sites of the ACADM gene, among which there were 7 reported mutations (p.T150Rfs*4, p.M1V, p.R206C, p.R294T, p.G310R, p.M328V, and p.G362E), 5 novel mutations (p.N194D, p.A324P, p.N366S, c.118+3A>G, and c.387+1del G), and 1 exon 11 deletion; p.T150Rfs*4 was the most common mutation (4/16). The detection rate of mutation sites in the ACADM gene was 80%. No phenotype-genotype correlation was observed. Dietary guidance and symptomatic treatment were given after confirmed diagnosis. No acute metabolic imbalance was observed within 4-82 months of follow-up. All neonates had good prognosis except one who had brain dysplasia.

CONCLUSIONS

MCADD is relatively rare in southern China, and p.T150Rfs*4 is a common mutation in the Chinese population. Cases with positive screening results should be evaluated by octanoylcarnitine C8 value and gene detection.

Solvent-free nanofluid with three structure models based on the composition of a MWCNT/SiO2 core and its adsorption capacity of CO2

A series of core/shell nanoparticle organic/inorganic hybrid materials (NOHMs) with different weight ratios of two components, consisting of multi-walled carbon nanotubes (MWCNTs) and silicon dioxide (SiO₂) as the core were synthesized. The NOHMs display a liquid-like state in the absence of solvent at room temperature. Five NOHMs were categorized into three kinds of structure states based on different weight ratio of two components in the core, named the power strip model, the critical model and the collapse model. The capture capacities of these NOHMs for CO₂ were investigated at 298 K and CO₂ pressures ranging from 0 to 5 MPa. Compared with NOHMs having a neat MWCNT core, it was revealed that NOHMs with the power strip model show better adsorption capacity toward CO₂ due to its lower viscosity and more reactive groups that can react with CO₂. In addition, the capture capacities of NOHMs with the critical model were relatively worse than the neat MWCNT-based NOHM. The result is attributed to the aggregation of SiO₂ in these samples, which may cause the consumption and hindrance of reactive groups. However, the capture capacity of NOHMs with the collapse model was the worst of all the NOHMs, owing to its lowest content of reactive groups and hollow structure in MWCNTs. In addition, they presented non-interference of MWCNTs and SiO₂ without aggregation state.

[Experts consensus on the management of the right heart function in critically ill patients]

To establish the experts consensus on the right heart function management in critically ill patients. The panel of consensus was composed of 30 experts in critical care medicine who are all members of Critical Hemodynamic Therapy Collaboration Group (CHTC Group). Each statement was assessed based on the GRADE (Grading of Recommendations Assessment, Development, and Evaluation) principle. Then the Delphi method was adopted by 52 experts to reassess all the statements. (1) Right heart function is prone to be affected in critically illness, which will result in a auto-exaggerated vicious cycle. (2) Right heart function management is a key step of the hemodynamic therapy in critically ill patients. (3) Fluid resuscitation means the process of fluid therapy through rapid adjustment of intravascular volume aiming to improve tissue perfusion. Reversed fluid resuscitation means reducing volume. (4) The right ventricle afterload should be taken into consideration when using stroke volume variation (SVV) or pulse pressure variation (PPV) to assess fluid responsiveness.(5)Volume overload alone could lead to septal displacement and damage the diastolic function of the left ventricle. (6) The Starling curve of the right ventricle is not the same as the one applied to the left ventricle,the judgement of the different states for the right ventricle is the key of volume management. (7) The alteration of right heart function has its own characteristics, volume assessment and adjustment is an important part of the treatment of right ventricular dysfunction (8) Right ventricular enlargement is the prerequisite for increased cardiac output during reversed fluid resuscitation; Nonetheless, right heart enlargement does not mandate reversed fluid resuscitation.(9)Increased pulmonary vascular resistance induced by a variety of factors could affect right heart function by obstructing the blood flow. (10) When pulmonary hypertension was detected in clinical scenario, the differentiation of critical care-related pulmonary hypertension should be a priority. (11) Attention should be paid to the change of right heart function before and after implementation of mechanical ventilation and adjustment of ventilator parameter. (12) The pulmonary arterial pressure should be monitored timingly when dealing with critical care-related pulmonary hypertension accompanied with circulatory failure.(13) The elevation of pulmonary aterial pressure should be taken into account in critical patients with acute right heart dysfunction. (14) Prone position ventilation is an important measure to reduce pulmonary vascular resistance when treating acute respiratory distress syndrome patients accompanied with acute cor pulmonale. (15) Attention should be paid to right ventricle-pulmonary artery coupling during the management of right heart function. (16) Right ventricular diastolic function is more prone to be affected in critically ill patients, the application of critical ultrasound is more conducive to quantitative assessment of right ventricular diastolic function. (17) As one of the parameters to assess the filling pressure of right heart, central venous pressure can be used to assess right heart diastolic function. (18). The early and prominent manifestation of non-focal cardiac tamponade is right ventricular diastolic involvement, the elevated right atrial pressure should be noticed. (19) The effect of increased intrathoracic pressure on right heart diastolic function should be valued. (20) Ttricuspid annular plane systolic excursion (TAPSE) is an important parameter that reflects right ventricular systolic function, and it is recommended as a general indicator of critically ill patient. (21) Circulation management with right heart protection as the core strategy is the key point of the treatment of acute respiratory distress syndrome. (22) Right heart function involvement after cardiac surgery is very common and should be highly valued. (23) Right ventricular dysfunction should not be considered as a routine excuse for maintaining higher central venous pressure. (24) When left ventricular dilation, attention should be paid to the effect of left ventricle on right ventricular diastolic function. (25) The impact of left ventricular function should be excluded when the contractility of the right ventricle is decreased. (26) When the right heart load increases acutely, the shunt between the left and right heart should be monitored. (27) Attention should be paid to the increase of central venous pressure caused by right ventricular dysfunction and its influence on microcirculation blood flow. (28) When the vasoactive drugs was used to reduce the pressure of pulmonary circulation, different effects on pulmonary and systemic circulation should be evaluated. (29) Right atrial pressure is an important factor affecting venous return. Attention should be paid to the influence of the pressure composition of the right atrium on the venous return. (30) Attention should be paid to the role of the right ventricle in the acute pulmonary edema. (31) Monitoring the difference between the mean systemic filling pressure and the right atrial pressure is helpful to determine whether the infusion increases the venous return. (32) Venous return resistance is often considered to be a insignificant factor that affects venous return, but attention should be paid to the effect of the specific pathophysiological status, such as intrathoracic hypertension, intra-abdominal hypertension and so on. Consensus can promote right heart function management in critically ill patients, optimize hemodynamic therapy, and even affect prognosis.

[Acetylsalicylic acid treatment enhanced immunomodulatory function of mesenchymal stem cells derived from gingiva]

OBJECTIVE

To analyze the role of acetylsalicylic acid (ASA) in immunomodulation of mesenchymal stem cells derived from gingiva (GMSCs), and to explore the role of ASA in enhancing the immumomodulation of GMSCs and the capacity of GMSCs to treat immune disorders and the underlying mechanism.

METHODS

Flow cytometry analysis were used to analyze the role of ASA in the expression of stem cells surface markers CD146, CD105, CD90, CD34 and CD45 in GMSCs,and the GMSCs proliferation was analyzed by 5-bromo-2-deoxyuridine (BrdU) staining and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The GMSCs and T cells co-culture system was established to analyze the role of ASA in immunomodulation of GMSCs by measuring T cell apoptosis using flow cytometry analysis and inflammatory cytokines using enzyme linked immunosorbent assay (ELISA). Further more, the dextran sulfate sodium (DSS) induced colitis mouse model was established and the mouse body weight, disease activity score, histological index and pathological change of colons were analyzed after GMSC infusion.

RESULTS

The proliferation of GMSCs and the expressions of CD105, CD146 in GMSCs were increased after ASA treatment. In the GMSCs and T cells co-culture system, GMSCs induced T cells apoptosis and inhibited interferon γ (IFN-γ) and tumor necrosis factor α (TNF-α) secretion by T cells, which were enhanced by ASA treatment. In vivo, GMSCs infusion could ameliorate DSS-induced colitis, including inhibited DSS-induced mouse body weight loss, decreased disease activity score and histological index, and decreased inflammation cells infiltration in colons, as shown by hematoxylin-eosin (HE) staining. Moreover, the therapeutic effects of GMSC infusion on DSS-induced colitis could be enhanced by ASA treatment. Mechanically, ASA treatment increased FasL expression of Fas/FasL death pathway in GMSCs to induce T cells apoptosis.

CONCLUSION

ASA enhanced immunomodulation of GMSCs and increased the capacity of GMSCs to ameliorate DSS-induced colitis in mice.

[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.

Genetic transformation and expression of transgenic lines of Populus x euramericana with insect-resistance and salt-tolerance genes

We characterized new transgenic varieties of poplar with multiple insect-resistant and salt stress tolerant genes. Two insect-resistant Bacillus thuringiensis (Bt) genes, Cry1Ac and Cry3A, and a salt-tolerant gene, Betaine aldehyde dehydrogenase (BADH) were inserted into a vector, p209-Cry1Ac-Cry3A-BADH. The clone of Populus x euramericana was transformed by the vector using the Agrobacterium-mediated method. Three transgenic lines were assessed using genetic detection and resistance expression analysis. PCR revealed that exogenous genes Cry1Ac, Cry3A, BADH and selective marker gene NPTII were present in three transgenic lines. Quantitative real-time PCR (qPCR) showed significant differences in the transcriptional abundance of three exogenous genes in different lines. Results of assays for Bt toxic proteins showed that the Cry1Ac and Cry3A toxic protein content of each line was 12.83-26.32 and 2108.91-2724.79 ng/g, respectively. The Cry1Ac toxic protein content of different lines was significantly different; the Cry3A toxic protein content was about 100 times higher than that of the Cry1Ac toxic protein. The insect-resistance test revealed the mortality rate of transgenic lines to Hyphantria cunea L1 larvae varied by 42.2-66.7%, which was significantly higher than non-transgenic lines. The mortality rate of L1 and L2 Plagiodera versicolora larvae was 100%. The insecticidal effect of transgenic lines to P. versicolora larvae was higher than that to H. cunea larvae. NaCl stress tolerance of three transgenic lines under 3-6% NaCl concentration was significantly higher than that of non-transgenic lines.

Interscapulothoracic resection of tumours of shoulder with a note on reconstruction

We retrospectively reviewed the outcomes of 33 consecutive patients who had undergone an extra-articular, total or partial scapulectomy for a malignant tumour of the shoulder girdle between 1 July 2001 and 30 September 2013. Of these, 26 had tumours which originated in the scapula or the adjacent soft tissue and underwent a classic Tikhoff-Linberg procedure, while seven with tumours arising from the proximal humerus were treated with a modified Tikhoff-Linberg operation. We used a Ligament Advanced Reinforcement System for soft-tissue reconstruction in nine patients, but not in the other 24. The mean Musculoskeletal Tumor Society score (MSTS) was 17.6 (95% confidence interval (CI) 15.9 to 19.4); 17.6 (95% CI 15.5 to 19.6) after the classic Tikhoff-Linberg procedure and 18.1 (95% CI 13.8 to 22.3) after the modified Tikhoff-Linberg procedure. Patients who had undergone a LARS soft-tissue reconstruction had a mean score of 18.6 (95% (CI) 13.9 to 22.4) compared with 17.2 (95% CI 15.5 to 19.0) for those who did not. The Tikhoff-Linberg procedure is a useful method for wide resection of a malignant tumour of the shoulder girdle which helps to preserve hand and elbow function. The method of soft-tissue reconstruction has no effect on functional outcome.

A phthalide derivative isolated from endophytic fungi Pestalotiopsis photiniae induces G1 cell cycle arrest and apoptosis in human HeLa cells

MP [4-(3′,3′-dimethylallyloxy)-5-methyl-6-methoxyphthalide] was obtained from liquid culture of Pestalotiopsis photiniae isolated from the Chinese Podocarpaceae plant Podocarpus macrophyllus. MP significantly inhibited the proliferation of HeLa tumor cell lines. After treatment with MP, characteristic apoptotic features such as DNA fragmentation and chromatin condensation were observed in DAPI-stained HeLa cells. Flow cytometry showed that MP induced G1 cell cycle arrest and apoptosis in a dose-dependent manner. Western blotting and real-time reverse transcription-polymerase chain reaction were used to investigate protein and mRNA expression. MP caused significant cell cycle arrest by upregulating the cyclin-dependent kinase inhibitor p27^KIP1 protein and p21^CIP1 mRNA levels in HeLa cells. The expression of p73 protein was increased after treatment with various MP concentrations. mRNA expression of the cell cycle-related genes, p21^CIP1, p16^INK4a and Gadd45α, was significantly upregulated and mRNA levels demonstrated significantly increased translation of p73, JunB, FKHR, and Bim. The results indicate that MP may be a potential treatment for cervical cancer.

Under 5 mortality rate and its contributors in Zhejiang Province of China from 2000 to 2009

OBJECTIVE

By analyzing the under 5 mortality rate (U5MR) and its contributors in Zhejiang Province of China from 2000 to 2009, we tried to understand the trend of U5MR change in Zhejiang Province and thus propose strategies to reduce child mortality.

METHODS

Thirty cities/counties/districts from Zhejiang Province were selected using stratified cluster sampling approach. Children under five years in these areas were enrolled as the subjects. The U5MR and its contributors were analyzed in terms of age, migration status of mothers, and other indicators using classic descriptive methods and Chi square test.

RESULTS

The U5MR in Zhejiang Province showed a declining trend from 14.83‰ in 2000 to 9.49‰ in 2009. In 2009, the U5MR was significantly higher in the rural areas than in the urban areas (9.14‰ vs.6.50‰, P<0.01) and among floating populations than among local residents (12.12‰ vs. 6.42‰, P<0.01). Preterm birth/low birth weight was the leading cause of U5MR in 2009. More specifically, preterm birth/low birth weight, congenital heart disease, and birth asphyxia were the top three causes of deaths among infants (<1 year), while drowning, traffic accidents, and accidental falls were the leading causes of deaths among children (1-4 years).

CONCLUSION

The U5MR in Zhejiang Province in 2009 differed between urban areas and rural areas and between floating populations and local residents. The main causes of death differ between infants and young children. Prevention of preterm birth/low birth weight and congenital anomalies will reduce infant death, while the main intervention for young children is to avoid accidental injuries.

Diagnosis and treatment of subclinical hypothyroidism detected by neonatal screening

BACKGROUND

This study was undertaken to explore the clinical outcome and prognosis of subclinical hypothyroidism detected by newborn screening.

METHODS

Newborn screening was conducted at 1156 health care institutions in Zhejiang Province from October 1999 to September 2006. Included were (1) infants who had thyroid-stimulating hormone (TSH) ≥ 20 mU/L, and normal or lower normal levels of triiodothyronine (T(3)) and thyroxine (T(4)) and (2) infants with TSH between 5.6 mU/L and 20 mU/L at a confirmatory examination and follow-up showing TSH levels ≥ 20 mU/L or delayed reduction in T(4) levels. These infants were considered as having subclinical hypothyroidism and levothyroxine (L-T(4)) at an initial dose of 3-5 μg/kg per day was administered. The levels of TSH and T(4), developmental quotient (DQ), and index of growth were evaluated.

RESULTS

A total of 204 infants met our criteria for subclinical hypothyroidism, with an incidence of 1/8809. After 2-4 weeks of standard therapy, serum TSH level dropped to normal and T(4) reached a higher normal level in all the 204 infants. Evaluations of 60 patients after 2 years of therapy showed that their average DQ was 101 ± 14.61, and body weight and height were within the normal ranges. Bone age test for 54 patients revealed normal development in 44, slightly retarded development in 7, and advanced development in 3.

CONCLUSIONS

Newborns with high TSH levels should be given particular attention to ensure early diagnosis. A L-T(4) dose of 3-5 μg/kg per day was effective in the initial treatment of subclinical hypothyroidism.

Sonographic measurement of thyroid volumes in healthy Chinese infants aged 0 to 12 months

OBJECTIVES

The purposes of this study were to determine thyroid volumes in healthy Chinese infants aged 0 to 12 months and to provide reference data for normal thyroid growth.

METHODS

A total of 408 healthy infants (229 male and 179 female) were enrolled in the study. The length, breadth, and depth of the thyroid gland were measured with sonography. The volume of each lobe was calculated by the correct ellipsoid formula (volume = length × breadth × depth × 0.479).

RESULTS

All of the infants' thyroids showed a normal uniform echo texture on sonography. The thyroid volume increased with age (r = 0.519; P < .001). Moreover, positive associations were noted between thyroid volume and height and weight (r = 0.517; P < . 001; r = 0.499; P < .001, respectively). No significant differences based on sex were found (t = 1.784; P = .075).

CONCLUSIONS

The thyroid volumes in these healthy Chinese infants varied from those reported in the published literature on healthy European infants. It is important to establish local reference ranges for thyroid volumes in healthy infants.

[The under-five mortality rate and the causes of death in Zhejiang Province between 2000 and 2009]

OBJECTIVE

To study the under-five mortality rate and the causes of death in Zhejiang Province between 2000 and 2009 in order to provide a basis for reducing the mortality rate in the region.

METHODS

By stratified random cluster sampling, all the children under 5 years old from 30 sampling areas of Zhejiang Province between 2000 and 2009 were enrolled. The under-five mortality rate and the leading causes of death were investigated by descriptive analysis and Chi-square test.

RESULTS

The under-five mortality rate demonstrated a decreased trend in Zhejiang Province between 2000 and 2009, with the under-five mortality rate of 14.83‰ in 2000 compared to 9.49‰ in 2009. In 2009, the under-five mortality rate in rural regions was significantly higher than that in urban regions (9.14‰ vs 6.50‰; P<0.01). Compared with the resident population, there were an increased under-five mortality rate in floating population (12.12‰ vs 6.42‰; P<0.01). Preterm delivery/low birth weight was the top death cause in children under 5 years old. The top three causes of death in infants less than 1 year old were preterm delivery/low birth weight, congenital heart disease and birth asphyxia compared to drowning, traffic accident and falling in children aged 1-4 years.

CONCLUSIONS

There are differences in the under-five mortality rate between rural and urban children as well as between the floating and resident population in 2009. The leading causes of death in different age groups are different. It is essential to reduce the mortality rate by preventing preterm delivery, low birth weight and congenital malformations to infants and preventing accidental injuries to children aged 1-4 years.

Taxonomic identification of a novel strain of Streptomyces cavourensis subsp. washingtonensis, ACMA006, exhibiting antitumor and antibacteria activity

Taxonomically diverse and genetically specialized, marine microorganisms have great potential in generating bioactive substances. A previous study isolated a novel actinomycete strain designated ACMA006 and revealed that the fermentation broth of ACMA006 (FBA6) significantly inhibited the growth of a series of tumor cell lines. The present study examined various characteristics of the ACMA006 strain, including its morphological, physiological, and biochemical nature, and the 16S rDNA gene sequence of ACMA006 and biological activity of FBA6. The ACMA006 strain grew at an optimal temperature of 28°C on nearly all media tested, except for Czapek's agar, producing an exuberant substrate and aerial hyphae. Phylogenetic analysis showed that the 16S rDNA gene sequence of ACMA006 was closely related to that of Streptomyces cavourensis subsp. washingtonensis, with a sequence similarity of nearly 100%. However, ACMA006 differed somewhat from Streptomyces cavourensis subsp. washingtonensis in terms of its morphological, physiological, and biochemical characteristics. According to a bioactivity assay, FBA6 strongly inhibited the growth of hepatocellular carcinoma cell line HepG2, while it was weakly cytotoxic to human normal hepatocytes LO2 according to an MTT assay. In addition, the growth of bacterial strains Bacillus subtilis and Staphylococcus aureus but not Escherichia coli, B. aerogenes, Pseudomonas fluorescence, and B. proteus was significantly suppressed by FBA6 as indicated by the filter paper disc method. Results of this study indicated that the strain ACMA006 represents a new strain of the Streptomyces cavourensis subsp. washingtonensis and that the active metabolites of this strain are candidates for utilization as anticancer or antibacterial agents.

Anomalous transport properties and phase diagram of the FeAs-based SmFeAsO1-xFx superconductors

We report the detailed phase diagram and anomalous transport properties of Fe-based high-T_{c} superconductors SmFeAsO1-xFx. It is found that superconductivity emerges at x approximately 0.07, and optimal doping takes place in the x approximately 0.20 sample with the highest T_{c} approximately 54 K. T_{c} increases monotonically with doping; the anomaly in resistivity from structural phase or spin-density-wave order is rapidly suppressed, suggesting a quantum critical point around x approximately 0.14. As manifestations, a linear temperature dependence of the resistivity shows up at high temperatures in the x<0.14 regime but at low temperatures just above T_{c} in the x>0.14 regime; a drop in carrier density evidenced by a pronounced rise in the Hall coefficient is observed below the temperature of the anomaly peak in resistivity. A scaling behavior is observed between the Hall angle and temperature: cottheta_{H} proportional, variantT;{1.5} for all samples with different x in SmFeAsO1-xFx system.

Study on the neurotoxic effects of low-level lead exposure in rats

OBJECTIVE

To investigate effects of developmental lead exposure on nitric oxide synthase (NOS) activity in different brain regions and on N-methyl-D-aspartate (NMDA) receptor mRNA expression in the hippocampus of rats. On the basis of these observations, we explored possible mechanisms by which lead exposure leads to impaired learning and memorizing abilities in children.

METHODS

A series of rat animal models exposed to low levels of lead during the developing period was established (drinking water containing 0.025%, 0.05% and 0.075% lead acetate). NOS activities in the hippocampus, the cerebral cortex, the cerebellum and the brain stem were determined with fluorescence measurement and levels of mRNA expression of the NMDA receptor 2A (NR2A) subunit and NMDA receptor 2B (NR2B) subunit in the rat hippocampus were measured with Retro-translation (RT-PCR).

RESULTS

There were no differences in the body weight of rat pups between any of the groups at any given time (P>0.05). The blood lead level of Pb-exposed rat pups showed a systematic pattern of change: at 14 d of age, it was lower than that at 7 d of age, then rising to the peak level at 21 d and finally falling to lower levels at 28 d. The hippocampal NOS activities of lead-exposed groups were all lower than that of the control group on the 21st and 28th day (P<0.01). NOS activities in the cerebellum of lead-exposed groups were all lower than that of the control group on the 21st and 28th day (P<0.001) and the NOS activity of the 0.025% group was significantly lower than that of the 0.05% and 0.075% groups on the 28th day (P<0.05). NOS activity in the cerebral cortex of the 0.075% group was significantly lower than that of the control, 0.025% and 0.05% groups on the four day spans (P<0.001). There was no significant difference of NOS activity in the brain stem between any lead-exposed group and the control group on the four day spans. In the 0.05% and the 0.075% groups, the level of NR2A mRNA expression was higher than that in the control group at 7 d and 14 d of age (P<0.05). In the 0.025% group, the level of NR2A was found to be higher than that in the control group at 7 d of age only (P<0.05). No significant differences were found for the levels of NR2B mRNA expression between any of the groups at any given time.

CONCLUSIONS

NOS activity in the hippocampus, the cerebral cortex and the cerebellum are inhibited by lead exposure. The degree of the inhibitory effect depends on the time span of exposure and the lead concentration. Developmental low-level lead exposure was found to raise the level of NR2A mRNA expression in the hippocampus of rats. Developmental low-level lead exposure does not affect the level of NR2B mRNA expression in the hippocampus.

Effect of lead exposure on the immune function of lymphocytes and erythrocytes in preschool children

OBJECTIVE

To investigate the influence of lead exposure on the immune function of lymphocytes and erythrocytes in preschool children.

MATERIALS AND METHODS

A group of 217 children three to six years of age from a rural area were given a thorough physical examination and the concentration of lead in blood samples taken from each subject was determined. The indices of lymphocyte immunity (CD+3CD+4, CD+3CD+8, CD+4CD+8, CD-3CD+19) and erythrocyte immunity (RBC-C3b, RBC-IC, RFER, RFIR, CD35 and its average fluorescence intensity) of 40 children with blood lead levels above 0.483 micromol/L were measured and compared with a control group.

RESULTS

The blood lead levels of the 217 children ranged from 0.11 micromol/L to 2.11 micromol/L. The CD+3CD+4 and CD+4CD+8 cells were lower (P<0.01) and the CD+3CD+8 cells were higher in the lead-poisoned subjects than those in the control group (P<0.05). CD+3 and CD-3CD+19 did not show significant differences. Although the RBC-C3b rosette forming rate was lower and the RBC-IC rosette forming rate was higher in the lead-poisoned group, this difference could not be shown to be statistically significant (P>0.05). RFIR was found to be lower in the lead-poisoned group (P<0.01). Compared with the control group, the positive rate of CD35 was not found to be significantly different in a group of 25 lead-poisoned children (P>0.05), while the average fluorescence intensity was lower in the lead-poisoned group (P<0.05).

CONCLUSION

Lead exposure can result in impaired immune function of T lymphocytes and erythrocytes in preschool children.

Improvement of ocular blood flow and retinal functions with puerarin analogs

Ischemic retinopathy and, particularly, age-related macular degeneration (AMD) are difficult eye diseases to treat. Since the etiology of these diseases is inadequate blood circulation in the retina and choroid, drugs which can improve blood circulation to these tissues should be beneficial to these diseases. Since fovea is avascular, AMD is closely related to choroidal vascular abnormalities, and drugs which show strong effects to increase choroidal blood flow would be particularly useful. Puerarin and all its derivatives, except ET (puerarin disubstituted with -CH2CH2OH), showed marked increase of choroidal blood flow at various time periods. Even ET showed a tendency to increase choroidal blood flow, though it was not statistically significant. As for b wave recovery, all puerarin analogs showed strong recovery of retinal function after ischemic insult for 30 min. These results indicate that puerarin analogs could be used for the treatment of ischemic retinopathy, and AMD in particular.

The still-face effect in Chinese and Canadian 3- to 6-month-old infants

Studies conducted in China examining cross-cultural differences in 3- to 6-month-olds used the still-face paradigm. In each study, 20 infants were in the experimental group (normal, still-face, normal interactions) and 20 in the control (3 normal periods). In Study 1, infants interacted with either their mother or their father; they looked and smiled less to the still-face of both parents. In Study 2, infants interacted with both their mother and a stranger, with order counterbalanced. Experimental groups showed similar still-face effects to both adults. The control group responded similarly to the stranger in both orders but responded less to their mother when she interacted 2nd. The data were compared with archival data from Canadian infants. Although Chinese infants took longer to begin smiling, responding was similar in both cultures, despite differences in mothers' behavior: Chinese mothers played with the infants' arms; Canadian mothers played with the legs.

The still-face effect in Chinese and Canadian 3- to 6-month-old infants

Studies conducted in China examining cross-cultural differences in 3- to 6-month-olds used the still-face paradigm. In each study, 20 infants were in the experimental group (normal, still-face, normal interactions) and 20 in the control (3 normal periods). In Study 1, infants interacted with either their mother or their father; they looked and smiled less to the still-face of both parents. In Study 2, infants interacted with both their mother and a stranger, with order counterbalanced. Experimental groups showed similar still-face effects to both adults. The control group responded similarly to the stranger in both orders but responded less to their mother when she interacted 2nd. The data were compared with archival data from Canadian infants. Although Chinese infants took longer to begin smiling, responding was similar in both cultures, despite differences in mothers' behavior: Chinese mothers played with the infants' arms; Canadian mothers played with the legs.

Effect of shoot tip and leaf removal on gravitropism in pea

Intact, light-grown pea (Pisum sativum L. cv. Alaska) seedlings were subjected to continuous horizontal gravistimulation and their growth and bending response compared with seedlings whose shoot tip and youngest leaf had been excised and with seedlings to which a counterweight to replace the mass of the decapitated tissue was added. While all seedlings achieved vertical orientation in 2 to 3 h, seedlings that were counterweighted bent upward at a significantly slower rate than the non-counterweighted, decapitated plants. In addition to this effect of mass on the rate of bending, decapitation also removed a major supply of auxin to cells in the bending zone which resulted in the slower bending of treated plants. Thus when using decapitation both the loss of mass and the time course of the response must be considered to understand its effect on gravitropism.

Influence of the shoot tip and leaves on circumnutation in green pea seedlings

Portions of the shoot system from young light-grown pea (Pisum sativum L.) seedlings were excised and circumnutation studied using time-lapse cinematography. Removal of the youngest leaf or shoot tip as well as ringing the stem with 20 mM triiodobenzoic acid severely restricted circumnutation. Treating the stump of the excised leaf with lanolin containing 10(-4) M indole-3-acetic acid or replacing the leaf with an artificial aluminum leaf both partially restored circumnutation. When the leaf was replaced with both auxin and an artificial leaf circumnutation continued at approximately the rate of the intact plant. This graphically shows the involvement of both auxin and gravitropism in circumnutation.

Microsurgical removal of epidermal and cortical cells: evidence that the gravitropic signal moves through the outer cell layers in primary roots of maize

There is general agreement that during root gravitropism some sort of growth-modifying signal moves from the cap to the elongation zone and that this signal ultimately induces the curvature that leads to reorientation of the root. However, there is disagreement regarding both the nature of the signal and the pathway of its movement from the root cap to the elongation zone. We examined the pathway of movement by testing gravitropism in primary roots of maize (Zea mays L.) from which narrow (0.5 mm) rings of epidermal and cortical tissue were surgically removed from various positions within the elongation zone. When roots were girdled in the apical part of the elongation zone gravitropic curvature occurred apical to the girdle but not basal to the girdle. Filling the girdle with agar allowed curvature basal to the girdle to occur. Shallow girdles, in which only two or three cell layers (epidermis plus one or two cortical cell layers) were removed, prevented or greatly delayed gravitropic curvature basal to the girdle. The results indicate that the gravitropic signal moves basipetally through the outermost cell layers, perhaps through the epidermis itself.

Microsurgical removal of epidermal and cortical cells: evidence that the gravitropic signal moves through the outer cell layers in primary roots of maize

There is general agreement that during root gravitropism some sort of growth-modifying signal moves from the cap to the elongation zone and that this signal ultimately induces the curvature that leads to reorientation of the root. However, there is disagreement regarding both the nature of the signal and the pathway of its movement from the root cap to the elongation zone. We examined the pathway of movement by testing gravitropism in primary roots of maize (Zea mays L.) from which narrow (0.5 mm) rings of epidermal and cortical tissue were surgically removed from various positions within the elongation zone. When roots were girdled in the apical part of the elongation zone gravitropic curvature occurred apical to the girdle but not basal to the girdle. Filling the girdle with agar allowed curvature basal to the girdle to occur. Shallow girdles, in which only two or three cell layers (epidermis plus one or two cortical cell layers) were removed, prevented or greatly delayed gravitropic curvature basal to the girdle. The results indicate that the gravitropic signal moves basipetally through the outermost cell layers, perhaps through the epidermis itself.

Effects of abscisic acid and xanthoxin on elongation and gravitropism in primary roots of Zea mays

We examined the involvement of abscisic acid (ABA) and xanthoxin (Xan) in maize root gravitropism by (1) testing the ability of ABA to allow positive gravitropism in dark-grown seedlings of the maize cultivar LG11, a cultivar known to require light for positive gravitropism of the primary root, (2) comparing curvature in roots in which half of the cap had been excised and replaced with agar containing either ABA or indole-3-acetic acid (IAA), (3) measuring gravitropism in roots of seedlings submerged in oxygenated solutions of ABA or IAA and (4) testing the effect of Xan on root elongation. Using a variety of methods of applying ABA to the root, we found that ABA did not cause horizontally-oriented primary roots of dark-grown seedlings to become positively gravitropic. Replacing half of the root cap of vertically oriented roots with an agar block containing ABA had little or no effect on curvature relative to that of controls in which the half cap was replaced by a plain agar block. Replacement of the removed half cap with IAA either canceled or reversed the curvature displayed by controls. When light-grown seedlings were submerged in ABA they responded strongly to gravistimulation while those in IAA did not. Xan (up to 0.1 mM) did not affect root elongation. The results indicate that ABA is not a likely mediator of root gravitropism and that the putative ABA precursor, Xan, lacks the appropriate growth-inhibiting properties to serve as a mediator of root gravitropism.