[A survey on the implementation of cardiovascular surgery for congenital heart disease in China between 2017 and 2021]

Objective: To investigate the inplementation of cardiovascular surgery for congenital heart disease (CHD) in China. Methods: A cross-sectional study was carried out. The CHD cardiovascular surgery data collected by the Chinese Society of Extracorporeal Circulation from 2017 to 2021 in 31 provinces (autonomous regions/municipalities) of China were retrospectively reviewed, the implementation of CHD cardiovascular surgery in different provinces, regions, general/specialized hospitals, and different age groups (whether≤18 years old) were summarized, and the correlation analysis between the number of surgeries carried out in each province/region and the gross regional product and the number of the regional population was performed. Results: Between 2017 and 2021, the annual volume of CHD cardiovascular surgery was 77 120, 77 634, 81 161, 62 663 and 71 492, respectively, showing a decreasing trend. Meanwhile, the proportion of CHD patients aged≤18 years who underwent cardiovascular surgery also showed a downward trend, from 79.8% (61 557/77 120) in 2017 to 58.6% (41 871/71 492) in 2021 (P=0.027). The number of surgical cases varied greatly among different provinces, including 4 provinces with≥5 000 cases and 9 provinces with 2 000-5 000 cases. In the five years, the number of CHD cardiovascular surgeries in Central and East China was the largest, accounting for 41.1%-45.5% of the total surgical cases. The proportion of CHD surgery cases≤18 years old was the highest in Southwest China (69.7%-87.4%) and the lowest in Northeast China (28.2%-68.9%). Except for 2021, the number of cases carried out by each region between 2017 and 2020 was correlated with the gross regional product (r=0.929, 0.929, 0.893 and 0.964, respectively, all P<0.05) and the population (r=0.821, 0.893, 0.821 and 0.857, respectively, all P<0.05). Hospitals that performed more than 100 operations (20.5%±1.2% of the total number of hospitals) completed 86.2%±1.2% of the total number of operations in China during the 5-year period. In 2017 and 2021, the number of CHD cardiovascular surgeries preformed in children's/women's and children's specialized hospitals accounted for 24.3% (18 772/77 120) and 23.8% (17 012/71 492) of the total number of cases in China, respectively. Conclusions: From 2017 to 2021, the number of cardiovascular surgery for CHD decreases slightly, but the proportion of surgery for adult CHD patients increases significantly.There is a strong correlation between the number of CHD operations in each region and their economic development status. The scale of CHD cardiovascular surgery performed in children's hospitals/women's and children's hospitals accounts for about a quarter of the total volume in China.

Trimester-specific effect of maternal co-exposure to organophosphate esters and phthalates on preschooler cognitive development: The moderating role of gestational vitamin D status

Organophosphate esters (OPEs) and phthalate acid esters (PAEs) are prevalent endocrine-disrupting chemicals (EDCs). Humans are often exposed to OPEs and PAEs simultaneously through multiple routes. Given that fetal stage is a critical period for neurodevelopment, it is necessary to know whether gestational co-exposure to OPEs and PAEs affects fetal neurodevelopment. However, accessible epidemiological studies are limited. The present study included 2, 120 pregnant women from the Ma'anshan Birth Cohort (MABC) study. The concentrations of tris (2-chloroethyl) phosphate (TCEP), 6 OPE metabolites and 7 PAE metabolites were measured in the first, second and third trimester using ultra-performance liquid chromatography-tandem mass spectrometry (LC-MS). Cognitive development of preschooler was assessed based on the Wechsler Preschool and Primary Scale of Intelligence-Fourth Edition (WPPSI-IV) of the Chinese version. Generalized estimating equations (GEEs), restricted cubic spline (RCS) and generalized additive models (GAMs) were employed to explore the associations between individual OPE exposure and preschooler cognitive development. The quantile-based g-computation (QGC) method was used to estimate the joint effect of PAEs and OPEs exposure on cognitive development. GEEs revealed significant adverse associations between diphenyl phosphate (DPHP) (β: -0.58, 95% CI: -1.14, -0.01), bis (2-butoxyethyl) phosphate(BBOEP) (β: -0.44, 95% CI: -0.85, -0.02), bis(1-chloro-2-propyl) phosphate (BCIPP) (β: -0.81, 95%CI: -1.43, -0.20) and full-scale intelligence quotient (FSIQ) in the first trimester; additionally, TCEP and bis(2-ethylhexyl) phosphate (BEHP) in the second trimester, as well as DPHP in the third trimester, were negatively associated with cognitive development. Through the QGC analyses, mixture exposure in the first trimester was negatively associated with FSIQ scores (β: -1.70, 95% CI: -3.06, -0.34), mono-butyl phthalate (MBP), BCIPP, and DPHP might be the dominant contributors after controlling for other OPEs and PAEs congeners. Additionally, the effect of OPEs and PAEs mixture on cognitive development might be driven by vitamin D deficiency.

[Use of indocyanine green fluorescence navigation in laparoscopic anatomical hepatectomy]

Objective: To examine the clinical value of fluorescence-guided indocyanine green (ICG) laparoscopic anatomical hepatectomy in the treatment of primary hepatocellular carcinoma. Methods: Data from patients diagnosed with hepatocellular carcinoma and who underwent laparoscopic hepatectomy with ICG fluorescence navigation in the Department of Liver Surgery and Liver Transplantation Center of West China Hospital between September 2020 and May 2022 were retrospectively collected. There were 53 males and 19 females, with an age of (55.5±12.9)years(range:42.6 to 68.4 years). Among them, 13 of the cases underwent laparoscopic anatomical liver resection(LALR) guided by tans-arterial ICG,43 of the cases received LAIR guided by portal vein negative ICG, and 16 of the cases received LALR positive by portal vein. Comparison among the three groups was performed by one-way ANOVA; and the rank sum test was used for comparison between groups. The counting data was expressed as percentage,and the χ² test or Fisher's exact probability method was used for comparison between groups. Results: (1) Postoperative pathology: Resection R0 was achieved in all operations. The maximum tumor diameter of the patients in the arterial staining group, the reverse staining group, and the positive staining group(M (IQR)) was 2.5 (2.4) cm, 3.0 (2.5) cm and 3.0(2.4) cm,respectively. There were no statistically significant differences in the maximum tumor diameter between the three groups (P=0.364). The minimum tumor margin was 1.1 (1.1) cm, 1.0 (1.0) cm, 1.1 (1.6) cm in the the arterial staining group, reverse staining group and the positive staining group, respectively. There was no significant difference in the margin among the three groups (P=0.878). (2) Operation conditions: the operation time of the arterial staining group, the negative staining group, and the positive portal staining group was (348±93)minutes,(277±112)minutes,and (295±116)minutes,respectively. There were no significant differences in operation time among the three groups (P=0.134). The intraoperative blood loss of the three groups was 80(150)ml,200(350)ml,and 100(150)ml,respectively. There was no statistically significant difference in intraoperative bleeding volume between the three groups(P=0.743). All cases were not transfused during the operation and were not converted to laparotomy. ALT in the arterial staining group was higher than in the negative staining group in the first two days after the operation ((559±398)IU/L307(257) IU/L, q=235.5,P=0.004;(611±389)IU/L(331±242) IU/L, q=265.2, P=0.002). There was only one case of a grade III complication (Clavien-Dindo grading system) postoperative complication in the negative and positive staining group of the portal vein, respectively. Tumor markers in all patients decreased to the normal range after 2 months of operation. Conclusion: Laparoscopic anatomical hepatectomy guided by ICG fluorescence through arterial staining and portal vein staining is safe and feasible for primary hepatocellular carcinoma treatment.

Exposure to multiple toxic metals and the risk of early embryonic arrest among women undergoing assisted reproductive techniques

BACKGROUND

Early embryonic arrest is a great challenge for in vitro fertilization. Whether exposure to toxic metals is associated with an increased risk of early embryonic arrest warrants investigation.

OBJECTIVES

Here, we conducted a case-control study in infertile women to estimate the associations between blood barium (Ba), arsenic (As), mercury (Hg), and lead (Pb) exposure levels and the risk of early embryonic arrest.

METHODS

Ba, As, Hg, and Pb exposure levels in fasting blood collected from 74 infertile women (123 cycles) with early embryonic arrest and 157 infertile women (180 cycles) without early embryonic arrest were measured by ICP-MS. Bayesian kernel machine regression (BKMR) was used to assess the association of exposure level of toxic metals mixture with the risk of early embryonic arrest as well as to evaluate which metal playing a leading role in the association, and then generalized estimating equations (GEEs) were used to evaluate the relationship between the selected harmful metal and the risk of early embryonic arrest. Finally, the potential causes of early embryonic arrest originating from the harmful metal exposure were explored.

RESULTS

Blood Ba levels were significantly higher in the case group than that in the control group (p = 0.009) rather than As, Pb and Hg. Results from BKMR showed that exposure to toxic metals mixture increased the risk of early embryonic arrest, with Ba playing a leading role (PIP = 0.9612). GEE analysis showed that high Ba exposure level was related with the increased risk of early embryonic arrest (p < 0.05) and it impacted on the oogenesis significantly.

CONCLUSIONS

Our study found that exposure to toxic metals mixture was associated with the increased risk of early embryonic arrest, and Ba contributed most to the increased risk. Higher Ba exposure in whole blood corresponds to a higher risk of early embryonic arrest and impacted on the oogenesis significantly.

Exposure to antibiotics and mental disorders in children: a community-based cross-sectional study

Although exposure to antibiotics at a critical developmental time window has been implicated in mental health in observational and experimental studies, very limited bio-monitoring data are available for exposure to antibiotics associated with child mental disorders. The goal of our study was to examine the association between urinary exposure of children to antibiotics and mental health. The participants were 278 children from 256 eligible families in the urban-rural fringe of Fuyang city in China since June in 2017. A single-point urine sample was collected to measure the antibiotic concentrations to characterize the exposure levels. A total of 45 antibiotics from nine classes and their two metabolites were monitored through liquid chromatography electrospray tandem mass spectrometry. We used multivariable regressions to estimate the covariate-adjusted associations between urine-antibiotic concentrations and mental impairments, as assessed using the parent version of Strengths and Difficulties Questionnaire. Among the participants, ciprofloxacin was associated with an increased risk of mental disorders at both lower concentrations (OR = 4.06; 95% CI 1.69-9.78) and higher concentrations OR = 6.04; 95% CI 2.59-14.08). After categorizing the detected antibiotics, the positive associations were observed between abnormal score in total difficulties and higher levels exposure to fluoroquinolones (OR = 2.83, 95% CI 1.38-5.80) and antibiotics preferred for veterinary use (PVAs) (OR = 3.20; 95% CI 1.41-7.27), respectively. Our findings suggest that ciprofloxacin, fluoroquinolones and PVAs, probably from contaminated food or environment, may be associated with child mental disorders.

Association of urinary phthalates metabolites concentration with emotional symptoms in Chinese university students

Previous studies have shown the associations between phthalates exposure and psychological behavior problems in children and adolescents, but such associations have not been fully elucidated in university students, especially among Chinese university students. This study aims to examine the association between urinary phthalates metabolites concentration and emotional symptoms in Chinese university students. A school-based cross-sectional survey was carried out among 990 university students aged 17-24 years from two universities in Anhui and Jiangxi provinces of China. Concentration of six phthalate metabolites in urine was determined by high-performance liquid chromatography-tandem mass spectrometry and the emotional symptoms were assessed by the 21-item Depression, Anxiety, and Stress Scale. The detection rate of six phthalate metabolites in urine ranged from 79.6% to 99.7%. The median concentration of six phthalate metabolites ranged from 2.90 to 119.64 ng/mL. The positive rates of depressive symptoms, anxiety symptoms, and stress were 17.4%, 24.8%, and 9.5%, respectively. After adjusting for the confounding variables, mono(2-ethyl-5-hydroxyhexyl) phthalate (MEHHP) was found to be associated with depressive symptoms (β = 8.84, P = 0.017), anxiety symptoms (β = 8.46, P = 0.015), and stress symptoms (β = 9.95, P = 0.012) in males; whereas, monobutyl phthalate (MBP) was found to be associated with depressive symptoms (β = 1.86, P = 0.002), anxiety symptoms (β = 1.81, P = 0.005), and stress symptoms (β = 1.48, P = 0.047) in females. Our study demonstrates that Chinese university students are widely exposed to phthalates; and high- and low-molecular weight phthalates are associated with emotional symptoms in males and females, respectively.

Retraction: Tuning the chemistry of graphene oxides by a sonochemical approach: application of adsorption properties

[This retracts the article DOI: 10.1039/C5RA02021B.].

Retraction: Simultaneous sorption and reduction of U(vi) on magnetite–reduced graphene oxide composites investigated by macroscopic, spectroscopic and modeling techniques

Retraction of ‘Simultaneous sorption and reduction of U(vi) on magnetite–reduced graphene oxide composites investigated by macroscopic, spectroscopic and modeling techniques’ by Wencai Cheng et al., RSC Adv., 2015, 5, 59677–59685, DOI: 10.1039/C5RA10451C.

[Association between the internal exposure levels of phthalates and executive function of preschool children]

Objective: To investigate the association between the internal exposure levels of phthalic acid esters (PAEs) and executive function (EF) of preschool children. Methods: Between October 2008 and October 2010, pregnant women who accepted pregnancy health care services in four municipal medical and health institutions in Ma'anshan city, Anhui Province, were recruited as study objects. A total of 5 084 pregnant women and 4 669 singleton live births were enrolled in this cohort. The follow-up study was conducted from April 2014 to April 2015. A total of 3 725 data-completed preschool children aged 3 to 6 years older entered in this study. The method of analysis seven metabolites of phthalates in urine was high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) and divided objects into low (P(0)-P(24)), medium (P(25)-P(74)) and high (P(75)-P(100)) groups according to their exposure concentrations. To investigate the executive function of preschool children, we used the Behavior Rating Inventory of Executive Function-Preschool Version (BRIEF-P). Univariate and multivariate statistical method was used to analyze the etiology association between the phthalate metabolites levels and preschool children's executive function. Results: In this study, 53.6% (1 997/3 725) of preschoolers were boys, children's age was (51.5±5.6) months. The detection rates of seven phthalate esters were: mono-n-methyl phthalate (MMP) was 99.89% (3 721/3 725); mono-ethyl phthalate (MEP) was 99.97% (3 724/3 725); mono-benzyl phthalate (MBzP) was 69.10% (2 574/3 725); mono-butyl phthalate (MBP), mono-(2-ethyl-5-oxohexyl) phthalate (MEOHP) and mono- (2-ethyl-5-hydroxyhexyl) phthalate (MEHHP) were 100.00% and mono-ethylhexyl phthalate (MEHP) was 99.95% (3 723/3 725). The median concentrations of the seven phthalate metabolites were: 17.71, 15.36, 0.07, 155.24, 10.73, 14.67, 3.59 µg/L, respectively. The median concentrations corrected by urinary creatinine were 29.65, 26.65, 0.12, 257.73, 17.94, 24.80, 6.27 µg/g Cr, respectively. The P(25) and P(7)5 concentration of the total PAEs metabolites corrected by urinary creatinine were 1.20 µmol/g Cr and 3.04 µmol/g Cr. After adjusted the relevant demographic information: children sex, children age in month, maternal age, parental education levels, household exposure to secondhand smoke and whether the child is the only child as confounds, multivariate logistic regression model showed that the risk of inhibitory self-control index (ISCI) dysplasia in MEHHP high concentration group and MEOHP high concentration group were 1.71 and 1.54 times (OR=1.71, 95% CI: 1.11-2.62; OR=1.54, 95% CI: 1.01-2.34) than in low concentration group. The risk of ISCI dysplasia in total PAEs metabolites high concentration group was 1.55 times (OR=1.55, 95% CI: 1.00-2.38) than in low concentration group. Conclusion: Phthalates exposure may damage the executive function of preschool children.

Maternal and cord blood fatty acid patterns with excessive gestational weight gain and neonatal macrosomia

BACKGROUND AND OBJECTIVES

This study evaluated the association of maternal excessive gestational weight gain with saturated and polyunsaturated fatty acid concentrations in maternal and cord serum.

METHODS AND STUDY DESIGN

We included 77 pairs of women and their newborns and classified them into three groups as follows: mothers with normal gestational weight gain and their babies with normal birth weight in group I (30 pairs), mothers with excessive gestational weight gain and their babies with normal birth weight in group II (30 pairs), and mothers with excessive gestational weight gain and their macrosomic babies in group III (17 pairs). Serum fatty acid concentrations were determined through gas chromatography-mass spectrometry.

RESULTS

No remarkable difference in maternal dietary intake was observed among the three groups. C16:0, C18:0, eicosapentaenoic acid, and docosahexaenoic acid concentrations were significantly higher in group III mothers than in group I mothers. Compared with group I neonates, total saturated and polyunsaturated fatty acid concentrations were significantly lower but total n-3 polyunsaturated fatty acid and docosahexaenoic acid concentrations were significantly higher in group II neonates (p<0.05). The n-6: n-3 ratio in maternal and cord serum was approximately 10:1 and 1.5:1, respectively.

CONCLUSION

Women with excessive gestational weight gain who deliver a macrocosmic neonate tend to have higher total saturated fatty acid concentrations but lower docosahexaenoic acid concentrations in their neonate cord serum. Fatty acid concentrations in maternal and cord serum are not associated with maternal dietary pattern.

Perinatal sulfamonomethoxine exposure influences physiological and behavioral responses and the brain mTOR pathway in mouse offspring

Sulfamonomethoxine (SMM) is widely used in the veterinary field in China. Although some clinical surveys have revealed that sulfonamide antibiotics cause adverse nervous system symptoms, the related mechanisms of maternal SMM exposure on the neurobehavioral development of offspring remain unclear. Here, we investigated the effects of perinatal SMM exposure on the physiological and behavioral responses of pubertal offspring mice and the underlying mechanisms. We randomly allocated pregnant mice into the groups treated with SMM at different doses and the saline-treated groups. Maternal mice were orally administered SMM daily from gestational day 1 to postpartum day 21. On postnatal day (PND) 22, the parameters of growth, endocrine hormones, and brain amino acid composition were assessed, as well as the brain transcript levels of key genes involved in the mammalian target of rapamycin (mTOR) signaling pathway. From PND 50 to 55, a battery of behavioral tests relevant to anxiety and memory were then administered. Analysis of the results indicated that the pups, particularly the pubertal female offspring, showed anxiety-like behavior. Moreover, the pubertal offspring showed cognitive impairments and fat accumulation. Furthermore, the relative mRNA expression of genes involved in the mTOR signaling pathway in females on PND 22 was elevated, whereas the expression of N-methyl-d-aspartate receptor 2B (NR2B) was reduced. Together, the results showed that perinatal SMM exposure perturbs neuroendocrine functions, and further alters gene expression in the mTOR pathway and NR2B gene expression early in life, which may contribute to brain dysfunction in pubertal life.

Cubic Mesoporous Silica Material as a Highly Efficient Solid Phase Extraction Sorbent for Bisphenol A, Tert-Nonylphenol from Water

Endocrine disrupting chemicals (EDCs), including bisphenol A (BPA), tert-nonylphenol (t-NP) in aqueous solutions, were extracted by cubic mesoporous silica material (MCM-48) and determined by high performance liquid chromatography--fluorometric detection simultaneously. The effect of eluent solvent and its volume, the pH of sample solution and the sample volume on the extraction recovery of MCM-48 composite for EDCs was investigated by the batch techniques. Comparative studies showed that MCM-48 was superior to C18 for the extraction of the more polar analyte bisphenol A and and at least as effective as C18 for the extraction of tert-nonylphenol. The results showed that the excellent recovery towards BPA (87.4%-95.6%) and t-NP (83.6%-96.3%) was achieved by using this method. The good linearity was obtained for BPA and t-NP (R2 > 0.993) at a range from 5 to 1000 μg L(-1). Under the optimum conditions, the detection limits of this method were 96 and 150 ng L(-1) for BPA and t-NP in water sample, based on a signal-to-noise ratio (S/N) of 3, respectively. This method has been also successfully applied for the determination of other EDCs in natural environmental water samples.

Adsorption of 4-n-Nonylphenol and Bisphenol-A on Magnetic Reduced Graphene Oxides: A Combined Experimental and Theoretical Studies

Adsorption of 4-n-nonylphenol (4-n-NP) and bisphenol A (BPA) on magnetic reduced graphene oxides (rGOs) as a function of contact time, pH, ionic strength and humic acid were investigated by batch techniques. Adsorption of 4-n-NP and BPA were independent of pH at 3.0- 8.0, whereas the slightly decreased adsorption was observed at pH 8.0-11.0. Adsorption kinetics and isotherms of 4-n-NP and BPA on magnetic rGOs can be satisfactorily fitted by pseudo-second-order kinetic and Freundlich model, respectively. The maximum adsorption capacities of magnetic rGOs at pH 6.5 and 293 K were 63.96 and 48.74 mg/g for 4-n-NP and BPA, respectively, which were significantly higher than that of activated carbon. Based on theoretical calculations, the higher adsorption energy of rGOs + 4-n-NP was mainly due to π-π stacking and flexible long alkyl chain of 4-n-NP, whereas adsorption of BPA on rGOs was energetically favored by a lying-down configuration due to π-π stacking and dispersion forces, which was further demonstrated by FTIR analysis. These findings indicate that magnetic rGOs is a promising adsorbent for the efficient elimination of 4-n-NP/BPA from aqueous solutions due to its excellent adsorption performance and simple magnetic separation, which are of great significance for the remediation of endocrine-disrupting chemicals in environmental cleanup.

Retracted Article: Tuning the chemistry of graphene oxides by a sonochemical approach: application of adsorption properties

The change in the chemical properties of graphene oxides (GOs) can be tuned by the sonochemical approach.

Removal of Pb(ii) by nano-titanium oxide investigated by batch, XPS and model techniques

The ion exchange and inner-sphere surface complexation were inferred as the adsorption mechanisms of Pb(ii) on nano-TiO₂.

Retracted Article: Simultaneous sorption and reduction of U(vi) on magnetite–reduced graphene oxide composites investigated by macroscopic, spectroscopic and modeling techniques

U(vi) removal mechanisms by magnetite–reduced graphene oxide composites with different mass% (from 33% to 93%) magnetite contents.

Polybrominated diphenyl ethers in mudsnails (Cipangopaludina cahayensis) and sediments from an electronic waste recycling region in South China

Mudsnails and sediments from an electronic waste recycling region in South China were chosen to study the polybrominated diphenyl ethers (PBDEs) bioavailability of mudsnail in different ambient levels. Significant (p < 0.05) correlations of biota-sediment accumulation factor (BSAF) versus the reciprocal of PBDE concentration in sediment (1/Sed) occurred in all quantitative PBDE congeners except BDE-209, showed that the BSAFs of PBDEs in mudsnails were increased with reciprocal increasing ambient levels. The BDE-183 correlation of mudsnail versus sediment (r = 0.580) was much lower than the correlation of BDE-209 versus BDE-183 in mudsnails (r = 0.812), indicated the main source of BDE-183 in mudsnails was from the debromination of higher brominated PBDEs.

Polybrominated diphenyl ethers in leaves and soil from typical electronic waste polluted area in South China

Polybrominated diphenyl ethers (PBDEs) in leaves and soil from typical e-waste polluted area in South China were investigated. The concentrations (ng/g dry weight) of PBDE congeners and summation operatorPBDE of five leaf samples were much lower than those in soil sample. The general patterns of summation di-BDEs to summation hepta-BDEs percentage distribution in leaf samples were similar to those of the soil sample, except the percentage of BDE209 which were lower than in soil. The percentages of summation di-BDEs to summation hepta-BDEs in soil were in the range of those in leaf samples. The results showed that the contamination of PBDEs in the leaf samples had good correlation with the soil around them.

[Spectroscopic characterization of structure of cerium incorporated MCM-48 mesoporous molecular sieve]

Cerium incorporated MCM-48 molecular sieves have been hydrothermally synthesized using a mixed template and pH adjusting route. The samples were characterized by various physicochemical methods, including X-ray diffraction, diffuse reflectance UV-Vis spectroscopy, FTIR spectroscopy, XRF spectroscopy, and nitrogen adsorption. These results reveal that cerium is incorporated in MCM-48 and it is in the form of well-dispersed tetra-coodinated cerium ion. The proper concentration of cerium and adjusting pH can keep Ce-MCM-48 with higher specific surface area , larger unit-cell parameter, narrower pore-size distribution, and thicker pore wall than those of MCM-48. These deduce higher activity, and better selectivity, thermal stability and hydrothermal stability than those of MCM-48. The concentration of Ce incorporated in MCM-48 affects the vibration of the framewoke Si of molecular sieves.

[Determination of benzo(a)pyrene in cigarette mainstream smoke by second-order-derivative synchronous fluorescence]

The synchronous fluorescence, first-order and second-order-derivative synchronous fluorescence spectra of BaP in cigarette mainstream smoke were studied. It was indicated that the second-order-derivative synchronous fluorescence spectrum could decrease the disturbances of BaP homologous compounds and background of sample. Hereby the present paper introduces a new method to determine BaP in cigarette mainstream smoke by solid-phase-extraction second-order-derivative synchronous fluorescence. The detection limit is 0.2 ng x mL(-1), the average recoveries of BaP are 80.2%-86.2%, and the RSD is 2.64%-3.02%.

Construction of transgenic Bacillus mucilaginosus strain with improved phytase secretion

AIMS

To construct a transgenic Bacillus mucilaginosus strain to increase the secretion capability of a wild-type isolate of B. mucilaginosus D4B1 to hydrolyse phytate phosphorus, which can be used as a microbial fertilizer in field application.

METHODS AND RESULTS

We constructed a phytase secreting expression vector pSP43 with a mini-Tn5 transposon and a Aspergillus fumigatus phytase expression cassette. The vector pSP43 was successfully transferred into the wild-type B. mucilaginosus using the particle bombardment method, and three transgenic strains with a stable copy of phytase expression cassette integrated into the chromosome of the B. mucilaginosus by Tn5 transposition were selected. The phytase activity of the engineered strains increased 36-46-fold when compared with the wild-type strain of D4B1.

CONCLUSIONS

The A. fumigatus phytase gene can be expressed under the direction of p43 promoter in B. mucilaginosus. The expression protein is secreted extracellularly and newly constructed strains showed a high phytase activity.

SIGNIFICANCE AND IMPACT OF THE STUDY

A transgenic Bacillus strain by the particle bombardment method was constructed.

Beta-chemokine, macrophage inflammatory protein-1beta (MIP-1beta), is highly expressed in diffuse type human gastric cancers

Chemokines have been shown to be expressed in some malignant or precancerous tissues. However, the role of these chemokines on tumor development or progression is not clear. The expression patterns of chemokines in gastric cancer tissues were examined in 86 surgically resected samples using immunohistochemistry. Macrophage inflammatory protein-1beta (MIP-1beta) was clearly detected in many gastric carcinoma cells. In most of the differentiated carcinomas, intracellular localization of MIP-1beta was detected in more than 5% of cancer cells, although the percentages of MIP-1beta-positive cells differed among each sample. Undifferentiated carcinomas showed contrasted staining pattern between solid type and non-solid (diffuse) type. MIP-1beta was totally absent in all the poorly differentiated carcinomas with solid type growth pattern (por1). In contrast, MIP-1beta was highly expressed in all of the non-solid type of poorly differentiated carcinoma (por2) and signet-ring cell carcinoma samples. In particular, MIP-1beta was strongly stained in carcinoma cells at the front of invasive lesions. In 43 diffuse type undifferentiated cancers, tumors with high expression of MIP-1beta exhibited significantly more lymph node metastasis. Our results suggest a possibility that MIP-1beta may be related to the scattering and invasion step of gastric carcinoma cells with undifferentiated phenotype.

Oolong tea polyphenol extract induces apoptosis in human stomach cancer cells

The exposure of human stomach cancer KATO III cells to oolong tea polyphenol extact [OTPE] containing oolong tea polyphenol trimer [OTP trimer] as a main component, led to both growth inhibition and the induction of apoptosis. Morphological change showing apoptotic bodies was observed in the cells treated with OTPE. The fragmentation by OTPE of DNA to oligonucleosomalsized fragments that are characteristics of apoptosis was observed to be concentration- and time-dependent. These data suggest that the growth inhibition by OTPE results from the induction of apoptosis in the KATO III cells.

Possible involvement of cyclophilin B and caspase-activated deoxyribonuclease in the induction of chromosomal DNA degradation in TCR-stimulated thymocytes

TCR engagement of immature CD4(+)CD8(+) thymocytes induces clonal maturation (positive selection) as well as clonal deletion (negative selection) in the thymus. However, the cell death execution events of thymocytes during the negative selection process remain obscure. Using a cell-free system, we identified two different DNase activities in the cytosol of in vivo anti-TCR-stimulated murine thymocytes: one that induced chromosomal DNA fragmentation, which was inhibited by an inhibitor of caspase-activated DNase, and another that induced plasmid DNA degradation, which was not inhibited by an inhibitor of caspase-activated DNase. We purified the protein to homogeneity that induced plasmid DNA degradation from the cytosol of anti-CD3-stimulated thymocytes and found that it is identical with cyclophilin B (Cyp B), which was reported to locate in endoplasmic reticulum. Ab against Cyp B specifically inhibited the DNA degradation activity in the cytosol of anti-CD3-stimulated thymocytes. Furthermore, recombinant Cyp B induced DNA degradation of naked nuclei, but did not induce internucleosomal DNA fragmentation. Finally, we demonstrated that TCR engagement of a murine T cell line (EL4) with anti-CD3/CD28 resulted in the release of Cyp B from the microsome fraction to the cytosol/nuclear fraction. Our data strongly suggest that both active caspase-activated DNase and Cyp B may participate in the induction of chromosomal DNA degradation during cell death execution of TCR-stimulated thymocytes.

Ichthyotoxic phloroglucinol derivatives from Dryopteris fragrans and their anti-tumor promoting activity

Two new ichthyotoxic compounds, aspidin PB (8) and dryofragin (9), along with three known phloroglucinol derivatives (1-3) and five terpenoids, were isolated from the whole herbs of Dryopteris fragrans by toxicity-directed fractionation using Oryzias latipes (Japanese name; medaka). The structures of the new compounds were determined by spectroscopic methods including 2D NMR techniques. Amongst the isolates, aspidin PB (8), dryofragin (9), and 1-5 exhibited potent ichthyotoxic activity against medaka with a median tolerance limit (TLm after 24 h) of 1.2-4.3 microg/ml. These compounds which are toxic to fish also had a potent inhibitory effect on the activation of Epstein-Barr virus early-antigen (EBV-EA) induced by tetradecanoyl phorbol 13-acetate, which is an in vitro short-term assay for anti-tumor promoting agents. Aspidin BB (2) and albicanol (4), which exhibited strong inhibitory effects on the EBV-EA activation, significantly suppressed an in vivo two-stage carcinogenesis on mouse skin.

Lineage-specific regulation of the murine RAG-2 promoter: GATA-3 in T cells and Pax-5 in B cells

Recombination activating gene-1 (RAG-1) and RAG-2 are expressed in lymphoid cells undergoing the antigen receptor gene rearrangement. A study of the regulation of the mouse RAG-2 promoter showed that the lymphocyte-specific promoter activity is conferred 80 nucleotide (nt) upstream of RAG-2. Using an electrophoretic mobility shift assay, it was shown that a B-cell-specific transcription protein, Pax-5, and a T-cell-specific transcription protein, GATA-3, bind to the -80 to -17 nt region in B cells and T cells, respectively. Mutation of the RAG-2 promoter for Pax-5- and GATA-3-binding sites results in the reduction of promoter activity in B cells and T cells. These results indicate that distinct DNA binding proteins, Pax-5 and GATA-3, may regulate the murine RAG-2 promoter in B and T lineage cells, respectively. (Blood. 2000;95:3845-3852)

The prevalence of NIDDM and IGT and related factors among residents in some areas of Hubei Province, China

The epidemiological survey of prevalence of NIDDM (non-insulin dependent diabetes mellitus) and IGT(impaired glucose tolerance) was conducted among 9450 residents aged 25-70 in some areas of Hubei Province, China. The results show that NIDDM and IGT prevalences are 2.62% and 4.48%, respectively. There is no significant difference between male and female (P > 0.05). The NIDDM prevalence in cities is slightly higher than that in countryside, but the difference is not significant (P > 0.05). However, the IGT prevalence in city is significantly higher than that in countryside (P < 0.01). The prevalence of both NIDDM and IGT is increasing along with the age of the population. It is also significantly related to the family history of NIDDM, hypertension, and high body mass index (BMI). By using stepwise logistic regression to analyse the risk factors of NIDDM, age (OR = 1.86), BMI(OR = 2.69), family history (OR = 2.84) and hypertension (OR = 2.23) entered the model (significance level is alpha = 0.05).

Monoclonal antibodies against the protein complex that contains the flagellar movement-initiating phosphoprotein of Oncorhynchus keta

We isolated and characterized several monoclonal antibodies against a protein complex containing the flagellar movement-initiating phosphoprotein (MIPP) that appears to play a crucial role in the initiation of flagellar movement in quiescent spermatozoa of Salmonid fish. The effects of the antibodies on the phosphorylation of MIPP, as well as on the initiation of movement, in model sperm cells were studied. Three monoclonal antibodies, namely, FMI7, FMI18, and FMI27, were found specifically to inhibit both the initiation of flagellar movement and the phosphorylation of MIPP. These antibodies did not recognize denatured MIPP; they only recognized the native antigen. FMI7 exclusively recognized the denatured form of a 38-kDa protein, which may possibly be a protein kinase responsible for the phosphorylation of MIPP. Immunofluorescence analysis in situ of model sperm cells with the antibodies showed that the antigen was localized predominantly in the basal structure of the spermatozoon. Thus, the results clearly demonstrate the involvement of MIPP in the initiation of flagellar movement and the control of flagellar motility.

Isolation and properties of a protein complex containing flagellar movement-initiating phosphoprotein from testes of a white salmon

Phosphorylation of a tyrosine residue within a 15-kDa protein has been found to play a role in the initiation of flagellar movement of quiescent spermatozoa of the rainbow trout, Salmo gairdneri [Morisawa & Hayashi (1986) Biomed. Res. 6, 181-184; Hayashi et al. (1987) J. Biol. Chem. 262, 16692-16698]. In order to find a more accessible source of the 15-kDa protein for biochemical studies, phosphorylation of proteins was studied in other organs from other species. Cell-free extracts from spermatozoa and testes of Salmonidae were prepared and all catalyzed the cAMP-dependent, Mg(2+)-requiring, but Ca(2+)-independent phosphorylation of the 15-kDa proteins. Protein from the testes of a white salmon, Oncorhynchus keta, was isolated by conventional purification methods. The 15-kDa protein in the cell-free extract was found to be complexed with several other proteins such that the 15-kDa protein and its phosphorylating activity were copurified. Isolation of a sufficient amount of the complex for the preparation of antibodies against the various constituents is now possible.

[Microspectrophotometric analysis of DNA content in duct epithelial proliferation and invasive carcinoma of the pancreas]

Nuclear DNA content of 131 pancreatic duct epithelial lesions, including 10 normal ducts, 30 intraductal proliferations with mild atypia (groups I-II), 30 with moderate atypia (group III), 24 with severe atypia (group IV), 14 of carcinoma in situ (group V), and 23 invasive carcinomas, was analyzed using microspectrophotometry. DNA histograms were classified into diploid, polyploid and aneuploid patterns. All of normal duct epithelia showed diploidy. Polyploid patterns were observed in 3 (10%) lesions of groups I-II, 17 (56.7%) of group III, 14 (58.4%) of group IV, 7 (50%) of group V, and 6 (26.1%) of invasive carcinomas, and aneuploid patterns were observed in 0%, 10%, 33.3%, 50% and 73.9%, respectively. This distribution of ploidy patterns revealed a gradual shift to the main ploidy from diploid to polyploid followed by aneuploid in proportion to the increase of the degree of epithelial atypia. The frequencies of polyploid cells in each lesion were determined. Their averages were 0.2% in groups I-II, 1.9% in group III, 3.4% in group IV, 4.4% in group V, and 6.7% in invasive carcinoma. The S+G2M phase fractions were significantly higher in proliferative epithelia than in normal. The results of this study suggest that duct epithelial proliferations of the pancreas have "genetic instability" leading to a serial clonal evolution and play a significant role in the progression of pancreatic duct cell carcinoma.