Four PQQ-Dependent Alcohol Dehydrogenases Responsible for the Oxidative Detoxification of Deoxynivalenol in a Novel Bacterium Ketogulonicigenium vulgare D3_3 Originated from the Feces of Tenebrio molitor Larvae.

Deoxynivalenol (DON) is frequently detected in cereals and cereal-based products and has a negative impact on human and animal health. In this study, an unprecedented DON-degrading bacterial isolate D3_3 was isolated from a sample of Tenebrio molitor larva feces. A 16S rRNA-based phylogenetic analysis and genome-based average nucleotide identity comparison clearly revealed that strain D3_3 belonged to the species Ketogulonicigenium vulgare. This isolate D3_3 could efficiently degrade 50 mg/L of DON under a broad range of conditions, such as pHs of 7.0-9.0 and temperatures of 18-30 °C, as well as during aerobic or anaerobic cultivation. 3-keto-DON was identified as the sole and finished DON metabolite using mass spectrometry. In vitro toxicity tests revealed that 3-keto-DON had lower cytotoxicity to human gastric epithelial cells and higher phytotoxicity to Lemna minor than its parent mycotoxin DON. Additionally, four genes encoding pyrroloquinoline quinone (PQQ)-dependent alcohol dehydrogenases in the genome of isolate D3_3 were identified as being responsible for the DON oxidation reaction. Overall, as a highly potent DON-degrading microbe, a member of the genus Ketogulonicigenium is reported for the first time in this study. The discovery of this DON-degrading isolate D3_3 and its four dehydrogenases will allow microbial strains and enzyme resources to become available for the future development of DON-detoxifying agents for food and animal feed.

Quantitative PCR assays for the species-specific detection of Fusarium graminearum sensu stricto and Fusarium asiaticum in winter wheat growing regions in China.

Fusarium graminearum species complex (FGSC) is one of the most devastating fungal plant pathogens of cereal crops worldwide, resulting in a corresponding mycotoxins contamination in cereal-based food. The detection of FGSC to study its population structure and species distribution is of great concern for the integrated control of mycotoxins contamination in grains entering food supply chains. In this study, real time quantitative PCR (RT-qPCR) and droplet digital PCR (ddPCR) methods were developed for the species-specific detection of Fusarium graminearum species complex in winter wheat growing regions in China. Primers and probes were designed basing the on the sequence of Fg-16 SCAR fragment (sequence characterized amplified regions analysis) and confirmed to make a distinguishment between the two prevailing species including Fusarium graminearum sensu stricto and Fusarium asiaticum. The assay specificity was tested against 24 isolates of target Fusarium species and several non-target Fusarium species that were frequently isolated from wheat in China. Consistent results could be obtained by the developed RT-qPCR and ddPCR assays, and both of them were sensitive enough for the detection of FGSC in these regions. Population structure and species distribution of FGSC in North China plain and Yangtze River plain by the developed qPCR assays accorded with previous results obtained by fungal isolation method. The newly developed qPCR assays are time-saving and will provide new insights during the routine surveillance of FGSC in winter wheat growing regions in China and possibly other countries.

Predictive models for assessing the risk of Fusarium pseudograminearum mycotoxin contamination in post-harvest wheat with multi-parameter integrated sensors.

Reliable prediction of the risk of mycotoxin contamination in post-harvest wheat will aid in improvement of the quality and safety. To establish the relationship between Fusarium pseudograminearum mycotoxins and CO2 production, changes in their respective concentrations were monitored for the artificial contamination of wheat under different values of water activities (0.84 aw, 0.92 aw, and 0.97 aw) and temperatures (20 ℃, 25 ℃, and 30 ℃). Water activity played a significant role in all these processes. CO2 concentration together with moisture content and temperature were used as the main parameters to establish DON and ZEN contamination prediction models. The prediction accuracy for DON was 98.15 % (R2 = 0.990) and 90.74 % for ZEN (R2 = 0.982). These models were combined with T/RH/MC/CO2 multi-parameter integrated sensors to form an early warning system, which offers a great prospect to minimise the risk of DON/ZEN contamination in post-harvest wheat.

Reduction of natural killer cells is associated with poor outcomes in patients with hepatitis B virus-related acute-on-chronic liver failure.

BACKGROUND AND AIMS: Natural killer (NK) cells are critical innate effectors that respond to viral infections and contribute to immunopathology. Here, we aimed to investigate the role of NK cells in hepatitis B virus-related acute-on-chronic liver failure (HBV-ACLF) and elucidate the underlying mechanism by examining their phenotypic and functional profiles. METHODS: We included patients with HBV-ACLF (n = 37) and chronic hepatitis B (n = 19), and healthy controls (n = 13) in our study. We examined the phenotype and function of different subsets of peripheral NK cells using flow cytometry and RNA-sequencing analysis, and screened liver NK cells using immunohistochemistry. We detected inflammatory cytokines using a Luminex assay. In addition, we analyzed the relationships between these parameters and disease severity. RESULTS: Peripheral NK cells were decreased and characterized by high expression of caspase-3, Ki67, CXCR3, NKG2D, NKp46, CD107a, and GM-CSF, and typified by higher cell migration and immune response by RNA-sequencing analysis in patients with HBV-ACLF than in those with chronic hepatitis B. Accumulations of CXCL-10 and NK cells were found in the liver, and excessive production of CXCL-10 in the peripheral blood contributed to the apoptosis of NK cells in vitro. The decrease in NK cells was associated with the level of HBV DNA and disease severity and had good prognostic performance in predicting the outcome of patients with HBV-ACLF through AUROC analysis. CONCLUSION: NK cells were significantly decreased and showed dysfunction of phenotypic and functional profiles across distinct subsets in the peripheral blood of patients with ACLF. Crosstalk between CXCL-10 and NK cells may mediate the unbalanced distribution of NK cells. Understanding the dysfunction and decrease in NK cells may provide new insights into ACLF pathogenesis.

Development and validation of a rapid and efficient method for simultaneous determination of mycotoxins in coix seed using one-step extraction and UHPLC-HRMS.

Coix seed is an important food and traditional Chinese medicine in China and other Asian countries. Notably, coix seed is currently being used as a traditional medicine for the treatment of COVID-19 in China. However, coix seeds are generally contaminated by mycotoxins, and this risk cannot be ignored. In this paper, we developed a method that involves direct extraction and UHPLC-HRMS analysis for the simultaneous detection of 24 mycotoxins in coix seeds. UHPLC-HRMS instrument and data acquisition parameters, and the sample pretreatment were optimised. One-step extraction showed several advantages compared to the three commercial solid-phase extraction clean-up methods, including ease of use, reduced time of sample preparation, low cost, good recovery, and acceptable matrix effect. The method validation results indicate that all mycotoxins have good linearity and sensitivity. Recoveries were between 74.2-101.1%, and RSD ranged from 0.1-5.8%. The LOQs for 24 mycotoxins were in the range of 0.5-100 µg/kg. To survey the contamination levels of these mycotoxins in commercial coix seeds, more than 70 samples were collected from Chinese markets and were analysed using the newly developed method. Zearalenone (positive ratio: 98.7%, range:1.1-1562 µg/kg), deoxynivalenol (positive ratio: 87%, range: 8.4-382.5 µg/kg), nivalenol (positive ratio: 85.7%, range: 26.8-828.2 µg/kg), fumonisin B1 (positive ratio: 84.4%, range:2.5-314.5 µg/kg), fumonisin B2 (positive ratio: 75.3%, range:1.6-72.8 µg/kg), fumonisin B3 (positive ratio: 48%, range:1.0-203.6 µg/kg), aflatoxin B1 (positive ratio: 29.9%, range: 0.39-14.7 µg/kg), sterigmatocystin (positive ratio: 29.9%, range: 1.4-51.6 µg/kg), and tenuazonic acid (positive ratio: 19.5%, range 36.1-105.7 µg/kg) were the most frequent mycotoxin contaminants. These results highlight the importance of routine monitoring and control of mycotoxins in coix seeds.

Discovery of CRR1-targeted copper deficiency response in Chlamydomonas reinhardtii exposed to silver nanoparticles.

The molecular mechanisms behind the adaptive responses for interactions between organisms and nanoparticles, such as silver nanoparticles (AgNPs), are of great concern. In this study, the transcriptome of freshwater alga Chlamydomonas reinhardtii was characterized via RNA sequencing (RNA-seq) after exposure to a nontoxic concentration of AgNPs (0.5 mg/L). The cytochrome c6 (CYC6) and ferredoxin-5 (FDX5) genes were identified with the greatest increase in expression level, which were indications of the copper deficiency in the algae. Gene set enrichment analysis also showed significant enrichment of copper deficiency responsive genes in the transcriptome of algae exposed to AgNPs. These results indicated that AgNPs induced a copper deficiency response in algae, and the excessive intracellular copper content suggested this was due to functional copper deficiency. This deficiency response was further validated to be regulated by transcription factor CRR1 (copper response regulator 1) according to the assays on the mutant strain with defect of CRR1. To the best of our knowledge, this is the first corroboration of a CRR1-targeted copper deficiency response in algae following AgNP exposure. Given the function of copper in fundamental metabolic pathways, such as photosynthesis and respiration, we propose a potential role of CRR1-targeted copper deficiency as an adaptation of algae after exposure to AgNPs.

Identification and Determination of Rubrofusarin, Rubrofusarin Isomer, and Their Quinone Forms in Grains Using High-Resolution Mass Spectrometry.

Fungi of the genus Fusarium can produce secondary metabolites such as naphthopyrones and naphthoquinones that are toxic and expected to threaten the food and feed safety. In this study, the occurrence of rubrofusarin, rubrofusarin isomer, and their quinone forms in grains was identified and confirmed using ultrahigh-performance liquid chromatography coupled with hybrid quadrupole orbital ion trap mass spectrometry (Q-Orbitrap MS). The quantitation of these compounds in grain samples was also investigated using Q-Orbitrap MS. The results showed the concentrations of rubrofusarin ranged from 3.278 to 33.82 µg/kg, from 0.815 to 61.86 µg/kg, and from 7.362 to 47.24 µg/kg for the maize, rice, and wheat samples, respectively. By comparison, the abundances of their quinone forms were relatively lower, and the concentration of quinone form of rubrofusarin isomer was relatively higher than that of quinone form of rubrofusarin. These compounds were also confirmed to coexist with other known Fusarium mycotoxins. The data-dependent tandem mass spectra obtained from the Q-Orbitrap MS were validated to provide a wealth of valuable information that allowed for advanced data interpretation for solid confirmation of these compounds in grains. To the best of our knowledge, this is the first study that concerns the occurrence and quantitation of rubrofusarin, rubrofusarin isomer, and their quinone forms in grains.

Development and Interlaboratory Study of a Liquid Chromatography Tandem Mass Spectrometric Methodfor the Determination of Multiple Mycotoxins inCereals Using Stable Isotope Dilution.

An efficient, rapid, accurate, and cost-effective method based on stable isotope dilution and LC tandem MS was developed for the determination of multimycotoxins in cereals. The samples were extracted using acetonitrile-water-acetic acid (70 + 29 + 1, v/v/v), followed by dilution and centrifugation without any further cleanup. The mycotoxins were separated on a C18 column. Interference due to matrix effects was efficiently compensated for with [13C]-labeled stable isotope internal standards. The method demonstrated excellent linear relations, with regression coefficients above 0.999. Spiked recoveries at three different concentrations ranged from 80.9 to 115.9%, and RSDs were below 14% for all mycotoxins. The trueness of the method was also verified by participating in two proficiency tests, and satisfactory z-scores (|z| < 1.1) were obtained. In addition, an international interlaboratory study was organized to evaluate the methods. Eight laboratories characterized recovery, repeatability, and reproducibility studies in wheat, maize, and barley. The interlaboratory results were analyzed according to ISO 5725-2. Cochran and Grubbs tests were used to remove outliers. The mean recoveries of all 16 mycotoxins ranged from 87 to 111%. Repeatability, reproducibility, and Horwitz ratio values were 3.5-16.2, 5.4-33.6, and 0.16-1.65%, respectively. The results demonstrate that the method is reliable to determine multimycotoxins in cereals.

Risk assessment for human health in a seleniferous area, Shuang'an, China.

Shuang'an in Ziyang is a typical high-selenium (Se) area in China, where human selenium (Se) poisoning was reported 30 years ago. To assess the risk of Se poisoning in the area, the Se content in agricultural soil, plant, and water in Naore, Shuang Hekou, and Lin Benhe villages of Ziyang was systematically investigated. The probable daily intake (PDI) was calculated on the basis of Se contents in food, water, and dietary habits to evaluate the risk of selenosis. Se content in hair from local habitants (32 men and 34 women) was determined to further verify the risk. Results showed that Se content in the soil ranged from 0.21 to 36.07 mg/kg, with a geometric means of 3.02 ± 5.16 mg/kg, respectively. Approximately 60% of soil reached the Se toxicity threshold (>3 mg/kg). The Se content in plants ranged from 0.02 to 17 mg/kg, with an average of 0.76 ± 2.51 mg/kg. Approximately 40% of the plant reached the toxicity standard (1 mg/kg). Se content in soil and plant of Naore village was significantly higher than that from two adjacent villages. The Se content in vegetables (on fresh weight basis) was higher than that in cereals. Se contents were 3.73 ± 9.08 and 1.32 ± 3.50 mg/kg in eggplant and pepper, respectively. The Se content in drinking water was 7.85 ± 6.04 µg/L, lower than the upper tolerable limit (40 µg/L) set by WHO. The Se content in stream water (18.5 µg/L) was significantly higher than that in drinking water because of soil erosion. The calculated PDI of habitants in Naore village (1801 µg/day) was significantly higher than that in Lin Benhe (666 µg/day) and Shuang Hekou (686 µg/day), all of which was higher than the tolerable upper Se intake (400 µg/day) set by WHO. The calculated blood Se content was relatively high, especially for habitants of Naore village (2783-2824 µg/L). Moreover, the Se content in the hair of local habitants reached as high as 12.72 ± 13.81 mg/kg, and 78.79% exceeded hair Se toxicity threshold (>3 mg/kg), which further verified the potential selenosis risk. Our study provides significant implications of the potential Se intoxication of local residents. Therefore, governments and other institutions should implement various measures to reduce the daily Se intake and to mitigate the associated health risks.

Cellular internalization and intracellular biotransformation of silver nanoparticles in Chlamydomonas reinhardtii.

It is necessary to elucidate cellular internalization and intracellular biotransformation in order to accurately assess the toxicity and fate of nanoparticles after interaction with organisms. Therefore, this work employed a combination of high resolution imaging and in situ detection spectroscopic techniques to systematically investigate the intracellular localization, morphology and chemical speciation of silver in the cells of Chlamydomonas reinhardtii, a unicellular freshwater green alga, after exposure to AgNPs coated with polyvinylpyrrolidone at a concentration of 2.0 mg/L. High resolution secondary ion mass spectrometry and high-angle annular dark field scanning transmission electron microscopy together with energy dispersive spectroscopy and selected area electron diffraction collectively confirmed that after 48 h of exposure, AgNPs entered the periplasmic space after cellular internalization into the algal cells. Silver was also found to coexist with sulfur inside the cytoplasm in both crystalline and amorphous forms, which were further identified as ß-Ag2S and silver thiolates with synchrotron X-ray absorption spectroscopy. In combination, these analyses demonstrated that silver inside algae could be attributed to the uptake and sequestration of Ag(+) ion released from AgNPs, which was further sequestrated into cellular compartments. This study provides solid evidence for particle internalization and biotransformation of AgNPs after interaction with algae.

Molecular-Scale Investigation with ESI-FT-ICR-MS on Fractionation of Dissolved Organic Matter Induced by Adsorption on Iron Oxyhydroxides.

Adsorption by minerals is a common geochemical process of dissolved organic matter (DOM) which may induce fractionation of DOM at the mineral-water interface. Here, we examine the molecular fractionation of DOM induced by adsorption onto three common iron oxyhydroxides using electrospray ionization coupled with Fourier-transform ion cyclotron resonance mass spectrometry (ESI-FT-ICR-MS). Ferrihydrite exhibited higher affinity to DOM and induced more pronounced molecular fractionation of DOM than did goethite or lepidocrocite. High molecular weight (>500 Da) compounds and compounds high in unsaturation or rich in oxygen including polycyclic aromatics, polyphenols and carboxylic compounds had higher affinity to iron oxyhydroxides and especially to ferrihydrite. Low molecular weight compounds and compounds low in unsaturation or containing few oxygenated groups (mainly alcohols and ethers) were preferentially maintained in solution. This study confirms that the double bond equivalence and the number of oxygen atoms are valuable parameters indicating the selective fractionation of DOM at mineral and water interfaces. The results of this study provide important information for further understanding the behavior of DOM in the natural environment.

[Effects of long-term fertilization on evolution of S forms in a red soil and a black soil].

Sulfur (S) forms in two contrasting soils (a red soil and a black soil) under different long-term fertilization treatments (from 1990 to 2011) from the National Long-term Monitoring Network of Soil Fertility and Fertilizer Effects of China were investigated using a fractionation scheme in order to explore the distribution and transportation of S with different forms in the soils. The soil samples were collected from the topsoil (0-20 cm) and subsoil (20-40 cm) horizons that were treated with no fertilizers (CK), nitrogen, phosphorus, and potassium fertilizers (NPK), or NPK plus organic manures (MNPK) since 1990. The results indicated that when compared with the CK, total S contents in the topsoil layers treated with NPK and MNPK were increased by 42% and 33% for the red soil, and by 6% and 76% for the black soil, respectively, while the total S in the subsoil layer was less affected by the fertilization treatments and obviously lower than in the topsoil layer except for the red soil treated with NPK. The main forms of inorganic S in the red soil and black soil were found to be available S and HCl-extracted S, respectively. The application of NPK and MNPK increased the available S by 447% and 102% in the topsoil layer of the red soil compared with CK, and facilitated the transportation of available S into the lower depth. In contrast, NPK and MNPK only increased the available S by 54% and 93% in the topsoil layer of the black soil, and showed a slight influence on available S in the subsoil. The organic S forms were predominantly composed of ester S and residual S in the two soils. Under long-term fertilization, the residual S significantly increased over 32% and 55% in the topsoil and subsoil layers, respectively, compared with CK. The ester S and carbon-bonded S, which were relatively active, were less affected by the fertilization treatments, but positively related to the level of organic carbon in each soil (P < 0.05). In addition, the results from the long-term experiments indicated that the contribution of S input from atmospheric deposition was significant and should not be neglected.

Selenium fractionation and speciation in agriculture soils and accumulation in corn (Zea mays L.) under field conditions in Shaanxi Province, China.

Upland and paddy soils, as well as corn samples, were collected in the selenosis area of Naore Village, Ziyang County, Shaanxi Province, China. A five-step sequential extraction procedure was used for selenium (Se) fractionation, including soluble Se, exchangeable Se and carbonate-bound Se, iron and manganese oxide-bound Se, organic matter-bound Se, and the residual Se fraction. Species of soluble Se in upland soils included Se(-2), Se(4+), and Se(6+). The results showed that soluble Se and exchangeable Se fractions accounted for less than 1% of the total Se in the upland soil, but approximately 16.1% in the paddy soil. Concentrations of residual Se were lower than those of iron and manganese oxide-bound Se and organic matter-bound Se in both upland and paddy soils. Iron- and manganese oxide-bound Se was the dominant fractions in upland soil, whereas organic matter-bound Se abounded in paddy soil. Concentrations (mg kg(-1)) of Se in the corn samples ranged from 0.05 to 14.5 in seed, 0.31 to 12.3in root, 0.09 to 9.15 in stalk, and 0.16 to 36.15 in leaf. Path analysis indicated that soluble Se(6+) significantly (P<0.05) affected Se accumulation in corn tissues directly, whereas the organic matter-bound Se had a significant (P<0.05) indirect effect. In conclusion, corn did not readily absorb a major portion of soil Se. However, organic matter-bound Se was an important fraction and source of plant Se in agricultural soil.

Individual and joint toxicity effects of Cu, Cr(III), and Cr(VI) on pakchoi: a comparison between solution and soil cultures.

The single and joint toxicity effects of Cu, Cr(III), and Cr(VI) on the root elongation of pakchoi in solution and soil were investigated. The median effective concentration (EC(50)) was determined to examine the toxic thresholds of the test elements. The results showed that individual contamination by Cu, Cr(III), or Cr(VI) can inhibit the root elongation of pakchoi. The EC(50) values of the test elements were 2.02 mg/L and 195.8 mg/kg, 62.2 mg/L and 1,773 mg/kg, and 6.88 mg/L and 8.08 mg/kg in solution and soil, respectively. Toxic unit (TU) was introduced to determine the outcome in combined tests, and different behaviors were observed in both solution and soil. The coexistence of Cu and Cr(III) in solution exhibited an antagonistic effect (EC(50mix) = 1.76 TU(mix)), whereas a synergistic effect was observed in soil (EC(50mix) = 0.76 TU(mix)). In contrast, combined Cu-Cr(VI) showed a less than additive toxicity both in solution and soil, with EC(50mix) values of 3.31 and 1.24 TU(mix). In conclusion, the coexistence of toxicity in Cu-Cr(III) and Cu-Cr(VI) differs from the toxicity exhibited individually by Cu, Cr(III), and Cr(VI). Heavy metal interaction also changes depending on the medium.

[Expressions of CD34 and CD117 in human hepatocellular carcinomas and the clinical significance].

To study the expressions of CD34 and CD117 in the tissues of hepatocelluar carcinoma (HCC) and to explore the relationship with clinical pathology and it's evaluation on the prognosis of HCC patients. The expressions of CD34 and CD117 were examined by two-step methods of PV-9000 of immunohistochemistry in 55 HCC cases, 10 liver cirrhotic specimens and 6 normal liver specimens. Clinical-pathological data, tumor recurrent rate and survival rate after hepatectomy were recorded and analyzed with Fisher's Exact Test, Pearson X2 Test, Kaplan-Meier, Log-Rank Test and Cox Regression. The positive expression of CD34 was found in 65.4% of HCC, 20% of cirrhostic liver specimens and 16.7% of normal liver specimens, respectively. Significant differences found among the three groups, and the CD34 expression was significantly associated with vessel embolus (X2 = 4.000, P = 0.046) and the histological grades (X2 = 11.008, P = 0.001). The positive expression of CD117 was 47.3%, 10% and 0% in HCC, cirrhotic liver specimens and normal liver tissues, respectively, and statistical differences esxisted among the three groups. The CD117 expression was dramatically related to the histological grades (X2 = 5.115, P = 0.024) and clinical stages (X2 = 15.459, P = 0.000). Median disease free survival time after hepatectomy was significantly shorter in the group with positive-expression of CD34 (X2 = 4.105, P = 0.043) and CD117 (X2 = 28.023, P = 0.000) than the negative-expressed groups, respectively. Multivariate analysis showed that CD117 expression status, serum AFP levels and the size of tumor were independently prognostic factors for HCC patients. Tthe results demonstrated that CD34 and CD117 might play an important role in liver carcinogenesis and the progression of HCC, and they might potentially serve as markers for HCC prognosis.

Molecular diagnosis of two families with classic congenital adrenal hyperplasia.

We investigated the genetic defects in two families with classic congenital adrenal hyperplasia (CAH). Clinical data and vein blood of the family members were collected, hormonal evaluation, karyotype analysis, ultrasound and CT scans were performed, and a direct-sequencing of PCR products of the candidate genes was used to identify the mutations. In family A, Patients A-II:1 and A-II:2 were found to be in a compound heterozygous state for mutations of p.I172N (g.1004T>A) in exon 4 and IVS2-13A/C>G (g.659A/C>G) in intron 2 in CYP21A2 gene, their father A-I:1 and mother A-I:2 were found to carry a heterozygous mutation of IVS2-13A/C>G (g.659A/C>G) and p.I172N (g.1004T>A) respectively. In family B, Patient B-II:1 was detected to carry only one heterozygous mutation of p.I172N; no other mutations in CYP11B1, CYP17A1 or HSD3B2 genes were detected. Her father B-I:1 carried a heterozygous mutation of p.I172N (g.1004T>A) and her mother B-I:2 was found to be a wild type in all the candidate genes. Obviously, patients A-II:1 and A-II:2 inherited the p.I172N (g.1004T>A)-bearing maternal allele and the IVS2-13A/C>G (g.659A/C>G)-bearing paternal allele. And this kind of compound heterozygous mutations caused simple virilising (SV) CAH. While patient B-II:1, whose phenotype was SV CAH too, was found to carry only one heterozygous mutation of the p.I172N (g.1004T>A)-bearing paternal allele, and needed further studies.

[Transformation of copper and chromium in co-contaminated soil and its influence on bioavailability for pakchoi (Brassica chinensis)].

Heavy metal fractions in soil play an important role in the bioavailability for plants. A pot experiment was carried out to study the transformation and bioavailability for pakchoi of exogenetic copper and hexavalent chromium in co-contaminated soil. The results showed that one month after tested heavy metals were added into soil, the chromium was present mainly in residual and organic bonded form while copper was mainly bound to hydrated oxides of iron and manganese as well as residual form. Lower concentrations copper (< or = 400 mg x kg(-1)) in soil could promote chromium transform from other forms to exchangeable form while higher concentrations copper (> or = 800 mg x kg(-1)) in soil would inhibit this transformation. Similarly, chromium in low concentrations (< or = 5 mg x kg(-1)) could facility copper transform to residual form while chromium in high concentrations (> or = 20 mg x kg(-1)) would reduce such transformation process. Both added chromium to soil polluted by high concentrations copper and added copper to high chromium content soil could promote the polluted soil reach quasi-equilibrium state. Additionally, adding copper in soil could inhibit chromium uptake of pakchoi by promoting soil OM-Cr transformed into RES-Cr. While adding chromium in soil could reduce copper uptake of pakchoi by stimulating the EXE-Cu transformed into the RES-Cu. Therefore, it is necessary to take into consideration the synthetic effects of copper and chromium when carrying on assessment and phytoremediation to co-contaminated soil.

[Correction of the epicanthal fold and angulus oculi using the Z-epicanthoplasty].

OBJECTIVE: To explore a new procedure for aesthetic correction of the medial epicanthal fold aim at the etiopathogenesis. METHODS: The new Z-epicanthoplasty devise the upper and inferior margin of angle of eye medial as one angle of the Z. RESULTS: From 2004 to 2006, 129 patients were treated by using the method. Follow-up 6 to 24 months, all patients were satisfied by eliminating the medial epicanthal fold without obvious scar. CONCLUSIONS: The method is more effect than traditionally Z-plasty. Our technique is a simple, advanced procedure that can be performed widely.

[Correlation of pathology in chronic hepatitis B to viral markers in serum and hepatic tissue].

OBJECTIVE: To investigate the relation of the viral markers in serum and those expressed by hepatocytes to pathological lesions of hepatic tissue in patients with chronic hepatitis B. METHODS: The relation of viral markers including HBsAg, HBsAb, HBeAg, HBeAb, HBcAb and HBV DNA in serum of 647 patients with chronic hepatitis B and HBsAg, HBcAg expressed by hepatocytes in 418 of these patients to pathological lesions of hepatic tissue was determined. RESULTS: Viral markers in serum and those expressed by hepatocytes in patients with chronic hepatitis B were closely correlated with pathological lesions of hepatic tissue. CONCLUSION: The degree of inflammation and fibrosis in hepatic tissue is milder in serum HBsAg, HBeAb, HBcAb positive and HBV DNA negative patients but more serious in those with negative hepatocytic expression of HBsAg and HBcAg. HBV DNA is not significantly associated with pathological lesions of hepatic tissue.

[Reconstruction of the remnant penis: a 52-case report].

OBJECTIVE: To explore the effects of the combined method of abdominal axial flap transposition and penile elongation for the treatment of the remnant penis. METHODS: Fifty-two cases of the remnant penis treated with the combined method from 1984 April to February 2004 were analyzed retrospectively. Follow-up ranged from 0.5 to 20 years postoperatively. RESULTS: The lengths (both in normal and erectile conditions) and the circumferences of the penis gained after operation were (5.6 +/- 1.4) cm, (6.8 +/- 2.5 cm and (6.9 +/- 2.3) cm respectively. The recovery rates of the sensory function were 94.2% and 100% in the glans (immediately and 3 months after operation) and 32.7%, 51.9% and 75% in the flap area (3, 6 and 12 months postoperatively). The two-point distinguishing sense in the glans and the flap area was (5.1 +/- 0.9) mm and(7.9 +/- 1.3) mm 5 years after operation. Early complications included distant flap necrosis (3 cases), disruption of the wound (2 cases), part necrosis of the skin graft in the abdominal wall (2 cases) and poor contours occurred in 4 cases in the later period because of the thickness of the flaps. All of them were corrected with satisfactory results. CONCLUSION: The combined method of abdominal axial flap transposition and penile elongation was recommendable for the treatment of the remnant penis because of its positive effects and less complications.