Dynamics of the Deformable Fluid Interface Interacting with an Approaching Solid under the Electrostatic Field

A theoretical model was developed to describe the dynamics of a deformable fluid interface interacting with an approaching solid without contact by both the attractive electrostatic and van der Waals (i.e., vdW) interaction, analogous to the situation in the experiments by electric force microscopy (i.e., EFM) or electric-surface force apparatus (i.e., E-SFA) involved in the soft fluid interface. On the basis of this model, a numerical study of the deformation of the fluid interface, the force-vs-separation behavior, and the critical limiting conditions of contact has systematically been carried out. Our results show that the surface pressure induced by the electrostatic interaction plays a more prominent role in the deformation of the fluid interface than the vdW interaction does, and there exists a principal length scale associated with the relative strength of the electrostatic field to the surface tension, affecting the fluid interface shape under the electrostatic field. It was also shown that both the force-distance curves and the corresponding curves of fluid interface deformation peak versus distance for various electrostatic fields satisfy the universal scaling power law. Moreover, an analytical solution to the Euler-Lagrange differential equation governing the deformation of the fluid interface under the external electric field is obtained, and two extended formulas for explicitly describing the principal length scales that respectively characterize the lateral and longitudinal deformations of the fluid interface were determined.

Using Fe biofortification strategies to reduce both Ni concentration and oral bioavailability for rice with high Ni

Due to naturally high Ni or soil Ni contamination, high Ni concentrations are reported in rice, raising a need to reduce rice Ni exposure risk. Here, reduction in rice Ni concentration and Ni oral bioavailability with rice Fe biofortification and dietary Fe supplementation was assessed using rice cultivation and mouse bioassays. Results showed that for rice grown in a high geogenic Ni soil, increases in rice Fe concentration from ∼10.0 to ∼30.0 μg g^-1 with foliar EDTA-FeNa application led to decreases in Ni concentration from ∼4.0 to ∼1.0 μg g^-1 due to inhibited Ni transport from shoot to grains via down-regulated Fe transporters. When fed to mice, Fe-biofortified rice was significantly (p < 0.01) lower in Ni oral bioavailability (59.9 ± 11.9% vs. 77.8 ± 15.1%; 42.4 ± 9.81% vs. 70.4 ± 6.81%). Dietary amendment of exogenous Fe supplements to two Ni-contaminated rice samples at 10-40 μg Fe g^-1 also significantly (p < 0.05) reduced Ni RBA from 91.7% to 61.0-69.5% and from 77.4% to 29.2-55.2% due to down-regulation of duodenal Fe transporter expression. Results suggest that the Fe-based strategies not only reduced rice Ni concentration but also lowered rice Ni oral bioavailability, playing dual roles in reducing rice-Ni exposure.

[Epidemiological characteristics and influencing factors of Blastocystis hominis infection among children with diarrhea under five years of age in Guangzhou City]

OBJECTIVE

To investigate the prevalence and influencing factors of Blastocystis hominis infection among children with diarrhea under five years of age in Guangzhou City.

METHODS

Children with diarrhea under 5 years of age admitted to Guangzhou Children's hospital, Guangzhou Maternity and Child Healthcare Hospital and Guangzhou Women and Children's Medical Center during the period between January 1 and December 31, 2020, were enrolled. Participants' demographics, living environments and health status were collected using questionnaire surveys. Stool samples were collected from participants and nucleic acid was extracted. B. hominis infection was identified using PCR assay and sequence alignment, and the factors affecting B. hominis infection among children with diarrhea under 5 years of age were identified using univariate analysis and multivariate logistic regression analysis.

RESULTS

A total of 684 children with diarrhea under 5 years of age were enrolled, including 468 male children and 216 female children, with a mean age of (1.79 ± 1.12) years. The overall prevalence of B. hominis infection was 4.97% [34/684, 95% confidential interval (CI): (3.59%, 6.86%)] among participants, and there was no significant difference in the prevalence of B. hominis infection between children with chronic [7.52% (20/266), 95% CI: (4.92%, 11.33%)] and acute diarrhea [3.35% (14/418), 95% CI: (2.01%, 5.54%)] (χ² = 5.983, P = 0.014). Multivariate logistic regression analysis identified keeping pet [odds ratio (OR) = 6.298, 95% CI: (2.711, 14.633)], drinking non-tap water [OR = 4.522, 95% CI: (1.769, 11.561)], lactose intolerance [OR = 4.221, 95% CI: (1.043, 17.087)], antibiotic use [OR = 0.125, 95% CI: (0.017, 0.944)] and chronic diarrhea [OR = 2.172, 95% CI: (1.018, 4.637)] as factors affecting B. hominis infection among children with diarrhea under 5 years of age in Guangzhou City.

CONCLUSIONS

B. hominis infections is detected in children with diarrhea under five years of age in Guangzhou City. Improving home environments and pet-keeping hygiene is recommended to reduce the likelihood of B. hominis infection among children.

[Immunoprotective effect of recombinant peptidyl-prolyl cis-trans isomerase from Babesia microti against B. microti infection in mice]

OBJECTIVE

To evaluate the immunoprotective effect of active immunization with recombinant peptidyl-prolyl cis-trans isomerase from Babesia microti against B. microti infection in mice.

METHODS

Female BALB/c mice at 6 weeks of age, each weighing approximately 20 g, were divided into the recombinant protein immunization group, the infection control group and the normal control group, of 25, 18, 15 mice in each group, respectively. Mice in the recombinant protein immunization group were given active immunization with recombinant BmPPIase protein, and 18 mice with the highest antibody titers were intraperitoneally injected with 100 μL of B. microti-infected whole blood 2 weeks after the last immunization. Mice in the infection control group were intraperitoneally injected with 100 μL of B. microti-infected whole blood, while 15 mice in the normal control group received no treatment. Blood samples were collected from mice in the recombinant protein immunization group and the infection control group on days 0 to 30 post-immunization for detection of B. microti infection, and blood samples were collected on days 0, 7, 14, 21, and 28 post-immunization for routine blood tests with a blood cell analyzer and for detection of serum cytokines using cytometric bead array.

RESULTS

Anti-BmPPIase antibodies were detected in 25 mice in the recombinant protein immunization group 2 weeks after the last immunization, with titers of 5 × 10³ to 8 × 10⁴. B. microti infection rate peaked in mice in both the recombinant protein immunization and the infection control group on day 7 post-immunization, with positive infection rates of 13.3% and 50.0%, and there were significant differences between the two groups in terms of B. microti infection rate on days 3 (χ²= 113.18, P < 0.01), 5 (χ² = 475.22, P < 0.01), 7 (χ² = 465.98, P < 0.01) and 9 post-infection (χ²= 18.71, P < 0.01), while the B. microti infection rate tended to be 0 in both groups on day 11 post-immunization. Routine blood tests showed higher red blood cell counts [(5.30 ± 0.50) × 10¹² to (9.87 ± 0.24) × 10¹² counts/L)] and hemoglobin levels [(89.67 ± 22.80) to (148.60 ± 3.05) g/L)] in the recombinant protein immunization group than in the infection control group on days 0 to 28 post-immunization. Cytometric bead array detected higher serum interferon-γ [(748.59 ± 17.56) to (3 858.28 ± 1 049.10) fg/mL], tumor necrosis factor-α [(6 687.34 ± 1 016.64) to (12 708.13 ± 1 629.79) fg/mL], interleukin (IL)-6 [(611.05 ± 75.60) to (6 852.68 ± 1 554.00) fg/mL] and IL-17a [(167.68 ± 185.00) to (10 849.27 ± 355.40) fg/mL] and lower IL-10 levels [(247.65 ± 138.00) to (18 787.20 ± 2 830.22) fg/mL] in the recombinant protein immunization group than in the infection control group during the study period.

CONCLUSIONS

Recombinant BmPPIase protein induces up-regulation of interferon-γ, tumor necrosis factor-α and presents a high immunoprotective activity against B. microti infection in mice, which is a potential vaccine candidate protein.

[Mechanism of hepatic fibrosis associated with Echinococcus: a review]

Echinococcosis is a zoonotic parasitic disease caused by Echinococcus infections, and this disorder may cause fibrosis of multiple vital organs, which may further progress into cirrhosis. Early-stage hepatic fibrosis is reversible, and unraveling the mechanisms underlying hepatic fibrosis induced by Echinococcus infections is of great significance for the prevention and treatment of early-stage hepatic fibrosis. Recently, the studies pertaining to hepatic fibrosis associated with Echinococcus infections focus on cytokines and immune cells. This review summarizes the advances in the mechanisms underlying host immune cells- and cytokines-mediated hepatic fibrosis in humans or mice following Echinococcus infections.

[CircRNA circTNPO1 promotes the proliferation and metastasis of osteosarcoma by sponging miR-338-3p]

Objective: To explore the effects of circTNPO1 on the proliferation and metastasis of osteosarcoma (OS) by sponging miR-338-3p. Methods: The expression of circTNPO1 on osteoblasts and multiple OS cell lines were detected by qRT-PCR. CircTNPO1 stable knockdown 143B cell line was constructed by sh-circTNPO1. Cell count kit 8 (CCK-8) assay and wound healing assay were applied to evaluate the proliferation and metastasis of this cell. Luciferase reporter assay was used to explore the binding between circTNPO1 and miR-338-3p. In xenograft tumor model, miR-338-3p inhibitor or its control was injected into the circTNPO1 knockdown tumors. The weight and size of the tumors were evaluated and Ki-67 expression was detected by immunohistochemistry. Results: The RNA expression of circTNPO1 in OS cell lines U2OS, HOS, MG63, 143B, ZOS and ZOSM were 2.73±0.27, 3.18±0.54, 4.33±0.52, 5.75±0.65, 4.50±0.49 and 3.96±0.35, respectively, higher than 1.00±0.09 in hFOB1.19 (P<0.001). CCK-8 assay revealed that after 48 h and 72 h, the absorbance of sh-circTNPO1 #1 was 0.81±0.05 and 1.09±0.06, while sh-circTNPO1 #2 143B cells was 0.84±0.04 and 1.2±0.04, which were sharply reduced compared with the control (1.00±0.06 and 1.49±0.06, P<0.001); after 48 h and 72 h, the absorbance of 143B cells transfected with circTNPO1 #1 and miR-338-3p (0.92±0.06 and 1.32±0.07) were higher than those of cells transfected with sh-circTNPO1 cells and miR NC (0.92±0.06 and 1.32±0.07, P<0.050). Wound healing assay demonstrated that the 24 hour-migration rates of sh-circTNPO1 #1 and sh-circTNPO1 #2 cells were (24.43±2.15)% and (39.70±4.20)% respectively, which were significantly lower than that of the control [(56.51±3.27)%, P<0.010]; the migration rates of sh-circTNPO1 #1+ miR NC and sh-circTNPO1 #1+ miR-338-3p inhibitor were (26.70±2.21)% and (46.10±5.71)%, with a significant difference (P<0.005). In xenograft tumor model, the weight and size of tumors in control, sh-circTNPO1 #1+ miR NC and sh-circTNPO1 #1+ miR-338-3p inhibitor mice were (458.80±158.10) mg, (262.50±82.09) mg, (395.40±137.60) mg and (593.00±228.40) mm(2,) (203.30±144.20) mm(2,) (488.60±208.60) mm(2,) respectively. Compared with control, sh-circTNPO1 tumors were significantly smaller (P<0.01). Injection with miR-338-3p inhibitor significantly reversed both the weight and size of tumors (P<0.05). Conclusion: CircTNPO1 promotes the proliferation and metastasis of OS by sponging miR-338-3p, which could be a new target for OS treatments.

Advances in the study of molecular identification technology of Echinococcus species

The larvae of Echinococcus (hydatidcyst) can parasitize humans and animals, causing a serious zoonotic disease-echinococcosis. The life history of Echinococcus is complicated, and as the disease progresses slowly after infection, early diagnosis is difficult to establish. Due to the limitations of imaging and immunological diagnosis in this respect, domestic and foreign scholars have established a variety of molecular detection techniques for the pathogen Echinococcus over recent years, mainly including nested polymerase chain reaction (PCR), multiplex PCR, real-time quantitative PCR, and nucleic acid isothermal amplification technology. In this article, the research progress of molecular detection technology for Echinococcus infection currently was reviewed and the significance of these methods in the detection and diagnosis of hydatid and hydatid diseases was also discussed.

[Effect of enhanced recovery after surgery on surgical stress response in patients with gastric cancer complicated with type 2 diabetes mellitus]

Objective: To investigate the effect of enhanced recovery after surgery on the stress response of gastric cancer patients complicated with type 2 diabetes mellitus. Methods: We retrospectively analyzed the data of 49 patients with type 2 diabetes who underwent radical gastrectomy for gastric cancer in the Department of gastroenterology of the Affiliated Hospital of Jiangsu University from Jan to Dec 2020. They were randomly divided into experimental group and control group according to different perioperative management measures. The perioperative C-reactive protein (CRP), white blood cell (WBC), interleukin-6(IL-6), insulin resistance (HOMA-IR), blood glucose fluctuation and postoperative recovery were compared between the two groups. Results: A total of 49 patients were enrolled in the study (23 in the experimental group and 26 in the control group). The degree of stress reaction of the experimental group was lighter than that of the control group. The levels of CRP were significantly different on the 5th and 7th day after operation, IL-6 was significantly different on the 1st, 3rd, 5th and 7th day after operation, WBC and HOMA-IR were significantly different on the 1st day postoperatively. And the changes of HOMA-IR and blood glucose in experimental group were more gentle than those in control group. All the differences were statistically significant(P<0.05). In the experimental group, the time of first anal exhaust, indwelling time of drainage tube or nasointestinal tube and the total hospitalization time were significantly shorter than those of the control group(P<0.05). Conclusion: ERAS can reduce the degree of inflammatory stress and the postoperative IR level promote the early recovery of patients with gastric cancer complicated with type 2 diabetes mellitus.

[The expression and clinical significance of long non-coding RNA GIHCG in cholangiocarcinoma]

Objective: To screen long non-coding RNA (lncRNA) related to the prognosis of cholangiocarcinoma patients, detect its expression in cholangiocarcinoma tissue, and analyze its clinical significance by analyzing The Cancer Genome Atlas (TCGA) database. Methods: Using limma package, survival package, and survival receiver operating characteristic curve (ROC) package of R software to analyze the data of cholangiocarcinoma in TCGA and screen the differentially expressed lncRNAs related to patient survival. Real-time PCR and Fish were used to detect the expression of lncRNA and analyze its correlation with the clinical characteristics of patients. Small interfering RNA was used to knock down the expression of lncRNA GIHCG, and its effect on the migration ability of cholangiocarcinoma cell lines was detected by Transwell. Results: The results of the comprehensive analysis of survival, ROC, and correlation analysis with clinical data showed that lncRNA GIHCG has a significant correlation with lymph node metastasis in patients with cholangiocarcinoma. The expression of lncRNA GIHCG in cholangiocarcinoma tissue is significantly increased, closely related to tumor size and lymph node metastasis. Transwell results showed that lncRNA GIHCG could promote the migration of cholangiocarcinoma cells. Conclusion: The expression of lncRNA GIHCG is significantly increased in cholangiocarcinoma tissues and is closely related to patient survival and lymph node metastasis. It is expected to become a new molecular marker for diagnosing or treating cholangiocarcinoma.

[Clinical and prognostic study of anti-N-methyl-D-aspartate receptor encephalitis children with paroxysmal sympathetic hyperactivity syndrome]

The data of clinical characteristics, medical cost and prognosis of 22 anti-N-methyl-D-aspartate receptor (anti-NMDAR) encephalitis children from the Department of Neurology, Capital Institute of Pediatrics between May 2018 and January 2021 were analyzed, and 6 of them occurred paroxysmal sympathetic hyperactivity syndrome (PSH). It was found that the anti-NMDAR encephalitis children with PSH had severer consciousness disorder [median Glasgow Coma Scale (GCS) score at admission: 7.5], longer duration of consciousness disorder (median time: 53 days), higher hospitalization cost (median cost: 230 000 RMB), severer neurological injury at onset [median modified Rankin Scale (mRS) score at admission: 4], and longer recovery time of neurological function (median time of mRS score recovered to 0-2: 7 months), compared with those without PSH (all P<0.05). Therefore, more attention should be paid to sympathetic excited symptoms of anti NMDAR encephalitis, and thus identify and intervene early on PSH to reduce the neurological damage and economic burden.

[Construction of a cDNA library for Sparganum mansoni and screening of diagnostic antigen cadidates]

OBJECTIVE

To construct a cDNA library of Sparganum mansoni and immunoscreen antigen candidates for immunodiagnosis of sparganosis mansoni.

METHODS

Total RNA was extracted from S. mansoni, and reversely transcribed into cDNA, which was ligated into the phage vector. These recombinant vectors were packaged in vitro to construct the SMART cDNA library of S. mansoni. Then, the cDNA library was immunoscreened with sera from patients with sparganosis mansoni to yield positive clones. The inserted fragments of positive clones were sequenced and subjected to homology analyses, and the structure and functions of the coding proteins were predicted.

RESULTS

The SMATR cDNA library of S. mansoni was successfully constructed. The titer of the cDNA library was 6.25 × 10⁶ pfu/mL, with a recombinant efficiency of 100%, and the mean length of the inserted fragments in the library was larger than 1 100 bp. A total of 12 positive clones were obtained by immunoscreening, and were categorized into Sm-I (Sm60-1), Sm-II (Sm58-1), Sm-III (Sm20-1) and Sm-IV (Sm22-3), with 1 134, 1 063, 883 bp and 969 bp long inserted fragments. Their coding proteins were highly homologous with the Spirometra erinaceieuropaei antigenic polypeptide, cytoplasmic antigen, ribosomal protein S4-like protein and unnamed protein product, respectively.

CONCLUSIONS

A SMART cDNA library of S. mansoni has been successfully constructed and 4 categories of positive clones have been identified, which provides a basis for further studies on diagnostic antigens for sparganosis mansoni.

Novel PvACR3;2 and PvACR3;3 genes from arsenic-hyperaccumulator Pteris vittata and their roles in manipulating plant arsenic accumulation

Arsenite (AsIII) antiporter ACR3 is crucial for arsenic (As) translocation and sequestration in As-hyperaccumulator Pteris vittata, which has potential for phytoremediation of As-contaminated soils. In this study, two new ACR3 genes PvACR3;2 and PvACR3;3 were cloned from P. vittata and studied in model organism yeast (Saccharomyces cerevisiae) and model plant tobacco (Nicotiana tabacum). Both ACR3s mediated AsIII efflux in yeast, decreasing its As accumulation and enhancing its As tolerance. In addition, PvACR3;2 and PvACR3;3 were expressed in tobacco plant. Localized on the plasma membrane, PvACR3;2 mediated both AsIII translocation to the shoots and AsIII efflux from the roots in tobacco, resulting in 203 - 258% increase in shoot As after exposing to 5 μM AsIII under hydroponics. In comparison, localized to the vacuolar membrane, PvACR3;3 sequestrated AsIII in tobacco root vacuoles, leading to 18 - 20% higher As in the roots and 15 - 36% lower As in the shoots. Further, based on qRT-PCR, both genes were mainly expressed in P. vittata fronds, indicating PvACR3;2 and PvACR3;3 may play roles in AsIII translocation and sequestration in the fronds. This study provides not only new insights into the functions of new ACR3 genes in P. vittata, but also important gene resources for manipulating As accumulation in plants for phytoremediation and food safety.

Dendritic cell TLR4 induces Th1-type immune response against Cryptosporidium parvum infection

The objective of this study was to investigate the mechanism of Toll-like receptor (TLR4)- mediated dendritic cell (DC) immune against Cryptosporidium parvum infection. C. parvum sporozoites were labeled with 5,6-carboxyfluorescein diacetate succinimidyl ester. Murine bone marrow-derived DCs were isolated, and divided into TLR4 antibody blocking (TAB; infected with 2 × 10⁵ labeled sporozoites and 0.5 μg TLR4 blocking antibody), TLR4 antibody unblocking (TAU; infected with 2 × 10⁵ labeled sporozoites), and blank control (BC; with 1.5 mL Roswell Park Memorial Institute 1640 medium) groups. The adhesion of Cryptosporidium sporozoites to DCs and CD11c⁺ levels were examined by fluorescence microscopy and flow cytometry. Male KM mice were orally injected with C. parvum. The proliferation of T lymphocytes in spleen, expression of cytokines in peripheral blood, and TLR4 distribution features in different organs were further determined by immunohistochemistry. A significantly higher expression of CD11c⁺ and higher C. parvum sporozoite adhesion were found in the TAU group compared with other groups. The expression of CD4⁺CD8^- /CD8⁺CD4^- in the spleen were obviously differences between the TAB and TAU groups. The expression of TLR4, interleukin IL-4, IL-12, IL-18 and IFN-γ improved in the TAU group compared with TAB group. Higher expression of TLR4 was detected in the lymph nodes of mice in the TAU group, with pathological changes in the small intestine. Hence, TLR4 could mediate DCs to recognize C. parvum, inducing Th1 immune reaction to control C. parvum infection.

[Prevalence and risk factors of Blastocystis hominis infections among AIDS patients in Nanchang City]

OBJECTIVE

To investigate the prevalence and risk factors of Blastocystis hominis infections among AIDS patients in Nanchang City.

METHODS

A cross-sectional questionnaire survey was conducted among AIDS patients in Nanchang City during the period between May and September, 2016. B. hominis infection was detected in patients'stool samples using a PCR assay, and the CD4⁺ T cell count was measured in subjects'blood samples. In addition, the risk factors of B. hominis infection in AIDS patients were identified using univariate and multivariate logistic regression analyses.

RESULTS

A survey was conducted in Nanchang City from May to September 2016. A total of 505 AIDS patients were investigated, and the prevalence of B. hominis infection was 4.16%. Univariate analysis revealed that B. hominis infection correlated with the occupation (χ² = 8.595, P = 0.049), education level (χ² = 14.494, P = 0.001), type of daily drinking water (χ² = 10.750, P = 0.020), root of HIV infections (χ² = 8.755, P = 0.026) and receiving anti-HIV therapy (χ² = 23.083, P = 0.001) among AIDS patients, and multivariate logistic regression analysis identified daily direct drinking of tap water as a risk factor of B. hominis infections [odds ratio (OR) = 7.988, 95% confidential interval (CI): (1.160, 55.004)] and anti-HIV therapy as a protective factor of B. hominis infection [OR = 0.183, 95% CI: (0.049, 0.685)].

CONCLUSIONS

The prevalence of B. hominis is 4.16% among AIDS patients in Nanchang City. Daily direct drinking of tap water is a risk factor, and anti-HIV therapy is a protective factor of B. hominis infection among AIDS patients living in Nanchang City.

microRNAs expression profiles in Schistosoma japonicum of different sex 14 and 28 days post-infection

Different miRNAs are involved in the life cycles of Schistosoma japonicum. The aim of this study was to examine the expression profile of miRNAs in individual S. japonicum of different sex before and after pairing (18 and 24 dpi). The majority of differential expressed miRNAs were highly abundant at 14 dpi, except for sja-miR-125b and sja-miR-3505, in both male and female. Moreover, it was estimated that sja-miR-125b and sja-miR-3505 might be related to laying eggs. sja-miR-2a-5p and sja-miR-3484-5p were expressed at 14 dpi in males and were significantly clustered in DNA topoisomerase III, Rap guanine nucleotide exchange factor 1 and L-serine/L-threonine ammonia-lyase. Target genes of sja-miR-2d-5p, sja-miR-31- 5p and sja-miR-125a, which were expressed at 14 dpi in males but particularly females, were clustered in kelch-like protein 12, fructose-bisphosphate aldolase, class I, and heat shock protein 90 kDa beta. Predicted target genes of sja-miR-3483-3p (expressed at 28 dpi in females but not in males) were clustered in 26S proteasome regulatory subunit N1, ATPdependent RNA helicase DDX17. Predicted target genes of sja-miR-219-5p, which were differentially expressed at 28 dpi in females but particularly males, were clustered in DNA excision repair protein ERCC-6, protein phosphatase 1D, and ATPase family AAA domaincontaining protein 3A/B. Moreover, at 28 dpi, eight miRNAs were significantly up-regulated in females compared to males. The predicted target genes of these miRNAs were significantly clustered in heat shock protein 90 kDa beta, 26S proteasome regulatory subunit N1, and protein arginine N-methyltransferase 1. To sum up, differentially expressed miRNAs may have an essential role and provide necessary information on clarifying this trematode's growth, development, maturation, and infection ability to mammalian hosts in its complex life cycle, and may be helpful for developing new drug targets and vaccine candidates for schistosomiasis.

[Prevalence and risk factors of Blastocystis infections among primary school students in Jiangjin District, Chongqing City]

OBJECTIVE

To investigate the prevalence and risk factors of Blastocystis infections among primary school students in Jiangjin District, Chongqing City.

METHODS

A cross-sectional questionnaire survey was conducted among students sampled from a primary school in Jiangjin District, Chongqing City on April, 2018, and their stool samples were collected for microscopic examinations, in vitro culture and PCR assays to analyze the prevalence of Blastocystis infections and subtype of the parasite. In addition, the risk factors of Blastocystis infections among primary school students were identified using univariate analysis and multivariate logistic regression analysis.

RESULTS

A total of 466 primary students were surveyed, and the subjects had a mean age of (9.81±1.66) years and included 236 males (50.64%) and 230 females (49.36%). The prevalence of Blastocystis infections was 15.24% (71/466) among the study students, and there was no significance difference in the prevalence between male and fe- male students (16.52% vs. 13.91%; χ2 = 0.616, P = 0.433). In addition, there was a significant difference in the prevalence of Blastocystis infections among grade 1 (6.35%, 4/63), grade 2 (5.17%, 3/58), grade 3 (21.74%, 15/69), grade 4 (25.30%, 21/83), grade 5 (10.19%, 11/108) and grade 6 students (20.00%, 17/85) (χ2 = 15.410, P = 0.009). There were four Blastocystis subtypes characterized (ST1, ST3, ST6 and ST7), in which ST6 was the most common subtype (45.07%, 32/71), followed by ST3 (25.35%, 18/71). Multivariate logistic regression analysis revealed that minority ethnicity [odds ratio (OR) = 4.259, 95% confidential inter- val (CI) : (1.161, 15.621)] and low maternal education level (primary school and below) [OR = 9.038, 95% CI: (1.125, 72.642)] were identified as risk factors of Blastocystis infection among primary school students in Jiangjin District, Chongqing City.

CONCLUSIONS

There is a high prevalence of Blastocystis infections detected among primary school students in Jiangjin District, Chongqing City, and ST6 and ST3 are predominant subtypes. Minority ethnicity and low maternal education level (primary school and below) are risk factors for Blastocystis infections in primary school students.

[A prospective cohort study on blood pressure control and risk of ischemic stroke in patients with hypertension]

Objective: To explore the association between blood pressure control and risk of ischemic stroke (IS) in patients with hypertension. Methods: A total of 5 488 patients with hypertension from 60 communities were randomly selected from 101 communities in 8 streets of Nanshan District in Shenzhen City by using two-stage sampling method. The social demographic characteristics, behavior and life style, coronary heart disease and diabetes were collected and the physical condition, blood pressure and blood biochemical indexes were measured. From April 1, 2010 to August 31, 2017 as the follow-up period, the incidence of IS was annually collected by using telephone survey. Cox proportional hazard regression model was used to analyze the relationship between blood pressure control, systolic blood pressure (SBP), diastolic blood pressure (DBP) and the risk of IS. Results: The age of all patients was (58.50±12.14) years old, including 2 712 males (49.42%) and 3 112 patients with well-controlled blood pressure (56.71%). During the follow-up period, 358 new cases of IS were confirmed, and the incidence density was 1 346.27/100 000 person-years. Cox proportional hazard regression model analysis showed after adjusting for confounding factors, unstable blood pressure control, SBP≥150 mmHg (1 mmHg=0.133 kPa; compared with SBP<120 mmHg), and DBP≥95 mmHg (compared with DBP<80 mmHg) were associated with risk of IS. The HR (95%CI) was 1.29 (1.04, 1.59), 2.00 (1.26, 3.17) and 1.52 (1.01, 2.64), respectively. Subgroup analyses showed these associations only existed in female patients with hypertension. The HR (95%CI) was 1.39 (1.05, 1.85), 2.53 (1.41, 4.56) and 1.73 (1.00, 3.36), respectively. Conclusion: Unstable blood pressure control increases the risk of IS in female patients with hypertension.

Pteris vittata coupled with phosphate rock effectively reduced As and Cd uptake by water spinach from contaminated soil

Arsenic (As) and cadmium (Cd) are ubiquitous in the environment and they are both toxic to humans. When present in soils, they can enter food chain, thereby threatening human health. Water spinach (Ipomoea aquatica) is an important leafy vegetable, which is widely consumed in Asian countries. However, it is efficient in taking up As and Cd from soils and accumulating them in the edible parts. Therefore, it is of significance to reduce its As and Cd content, especially in contaminated soil. In this study, pot experiments were conducted to investigate the ability of As-hyperaccumulator Pteris vittata in reducing As and Cd uptake by water spinach under different phosphorus treatments. P. vittata was grown for 60 d in a contaminated-soil amended with P fertilizer (+P) or phosphate rock (+PR), followed by water spinach cultivation for another 30 d. Plant biomass, As and Cd contents in plants and soils, and soil pH were analyzed. We found that, P. vittata coupled with PR decreased the As concentration in water spinach shoots by 42%, probably due to As uptake by P. vittata. Moreover, P. vittata decreased the Cd accumulation in water spinach by 24-44%, probably due to pH increase of 0.47-0.61 after P. vittata cultivation. Taking together, the results showed that P. vittata coupled with PR decreased the As and Cd content in water spinach, which is of significance for improving food safety and protecting human health.

Parasitological and molecular detection of human fascioliasis in a young man from Guizhou, China

A 24-year-old man born in Guizhou province was diagnosed with obstructive jaundice and bile duct stones in 2013. Four living trematodes were found during laparotomy and cholecystectomy. Based on the morphology and molecular genetics analysis of internal transcribed spacer and pcox1 genes of the flatworm specimens, the trematodes from the patient were confirmed to be Fasciola hepatica. This report provided the clinical and molecular diagnosis information on human fascioliasis, which is an emerging sanitary problem still ignored in China. Human fascioliasis constantly occurs due to climatic changes and frequency of human travel. Therefore, it deserves more attention from physicians working in both developing and developed countries.

[Surveillance and control strategy of imported schistosomiasis mansoni: an expert consensus]

In 1980s, Biomphalaria straminea, an intermediate host of Schistosoma mansoni, was found in Shenzhen City, Guangdong Province, China, and currently, this snail has colonized in Shenzhen City and spread to peripheral cities involving of Dongguan and Huizhou. Since imported cases infected with S. mamoni have been reported from time to time in China, Mainland China is facing the potential risk of transmission of schistosomiasis mansoni. With the deepening of the opening-up policy, notably the implementation of the Belt and Road Initiative, there is an increase in the risk of transmission of schistosomiasis mansoni in Mainland China. Increasing the understanding on schistosomiasis mansoni, improving the awareness toward schistosomiasis mansoni prevention and control, and identifying, reporting and managing imported cases with S. mansoni infection or pathogen carriers, are of particular importance to prevent the development of entire life cycle of S. mansoni and the resultant schistosomiasis mansoni transmission in China. To protect public health, a consensus has been reached pertaining to the surveillance and control strategy of imported schistosomiasis mansoni by Chinese infectious disease experts and parasitologists, with aims to improve the awareness and capability for the diagnosis, treatment and control of imported schistosomiasis mansoni among Chinese disease control and prevention institutions and medical institutions, and decrease and even eliminate the risk of schistosomiasis mansoni transmission in China.

Determination of Ginsenosides (Ginseng Saponins) in Dry Root Powder from Panax ginseng, Panax quinquefolius, and Selected Commercial Products by Liquid Chromatography: Interlaboratory Study

Twelve collaborating laboratories assayed 4 products, namely, Panax ginseng, Panax quinquefolius, and 2 ginseng products, for 6 ginsenosides: Rb1, Rb2, Rc, Rd, Re, andRg1. Collaborators also received a negative control for the recovery study. Pure ginsenosides were provided as reference standards for the liquid chromatography (LC) analysis and the system suitability tests. The LC analyses were performed on the methanol extract using UV detection at 203 nm. For P. ginseng, individual ginsenosides were consistent in their means; repeatability standard deviations (RSDr)rangedfrom4.17to5.09% and reproducibility standard deviations (RSDR) ranged from 7.27 to 11.3%. For P. quinquefolius, the Rb1 and Rb2 ginsenosides were higher and lower in concentration than P. ginseng, with RSDr values of 3.44 and 6.60% and RSDR values of 5.91 and 12.6% respectively, and other analytes at intermediate precisions. For ginseng commercial products, RSDr values ranged from 3.39 to 8.12%, andRSDR values ranged from 7.65 to 16.5%. A recovery study was also conducted for 3 ginsenosides: Rg1, Re, andRb1. The average recoveries were 99.9, 96.2, and 92.3%, respectively. The method is not applicable for the determination of Rg1 and Re in ginseng product at levels &lt;300 mg/kg.

[Prevalence and risk factors of Blastocystis hominis infection in inpatients in Jiangjin District, Chongqing City]

OBJECTIVE

To understand the prevalence and risk factors of Blastocystis hominis infection in inpatients in Jiangjin District, Chongqing City.

METHODS

A cross-sectional study was conducted in a community hospital in Jiangjin District, Chongqing City, and the inpatients were surveyed by questionnaires. After obtaining the informed consent from the inpatients or legal guardians, the stool and blood samples were collected and examined by microscopy and PCR from April 17 to May 1, 2018. The univariate analysis and logistic regression analysis were used to analyze the risk factors of the B. hominis infection.

RESULTS

A total of 198 hospitalized patients were investigated, and the infection rate of B. hominis was 10.61% (21/198), and the infection rate of the females (12.10%) was higher than that of the males (8.11%), but the difference was not statistically significant. The highest rate of infection was 19.23% in the age group of 10 to 20 years, followed by 17.74% in the age group of 60 years and above, and the lowest rate was 2.38% in the age group of 20 to 40 years. The difference in infection rates of B. hominis among the different age groups was statistically significant (P < 0.05). The infection rate of B. hominis in the people who used dry pail latrines was 33.30%, which was higher than that of the people who used water flush toilets (9.10%) (P < 0.05). The genotypes of B. hominis were ST1, ST3, ST6 and ST7, and ST6 and ST3 being the most predominant genotypes which accounted for 47.62% (10/21) and 38.10% (8/21) respectively, and among the infected males, the genotypes were only ST3 and ST6. The multiple logistic regression analysis showed that among the factors affecting B. hominis infection, only keeping pets was a risk factor [OR = 3.798, 95% CI (1.245, 11.581), P < 0.05].

CONCLUSIONS

A high prevalence of B. hominis infection is found in the inpatients in Jiangjin District, Chongqing City, the predominant genotypes are ST6 and ST3, and keeping pets may be one of the main risk factors.

[Epidemiological characteristics and risk factors of Blastocystis hominis infection among patients with HIV/AIDS in Fuyang City Anhui Province]

OBJECTIVE

To investigate the prevalence and risk factors of Blastocystis hominis infections among patients with HIV/AIDS in Fuyang City, Anhui Province.

METHODS

A cross-sectional study was conducted in Fuyang City, Anhui Province in 2016. The demographic and socioeconomic status, and the lifestyle and production style were collected using a questionnaire survey. B. hominis DNA was detected in subjects'stool samples using a PCR assay, and the CD4+ T lymphocyte count and HIV viral load were measured in the subjects' blood samples. The risk factors of B. hominis infections among patients with HIV/AIDS were identified using univariate and multivariate logistic regression analyses.

RESULTS

A total of 398 HIV/AIDS patients were enrolled in this study, with a mean age of 49.3 years, a mean body weight of 55.9 kg and a mean height of 164.4 cm. The prevalence of B. hominis infection was 6.78% in the study subjects, and no gender- (χ² = 1.589, P = 0.207), education level- (χ² =0.508, P = 0.776), marital status- (χ² = 0.419, P = 0.811) or occupation-specific prevalence (χ² = 2.744, P = 0.615) was detected. Among the patients with HIV/AIDS, there were no significant differences in the age (t = 0.370, P = 0.712), height (t = 1.587, P =0.113), body weight (t = 0.516, P = 0.606), CD4⁺ T lymphocyte count (t = 1.187, P = 0.230) or HIV viral load (t = 0.193, P =0.496) between B. hominis-infected and uninfected individuals. Dinking non-tap water [OR = 6.554, 95% CI: (1.876 to 22.903)] and keeping dogs [OR = 5.895, 95% CI: (2.017 to 17.225)] were identified as risk factors for B. hominis infection in patients with HIV/AIDS.

CONCLUSIONS

The prevalence of B. hominis infection is high in HIV/AIDS patients, and drinking non-tap water and keeping dogs are risk factors for B. hominis infection among HIV/AIDS patients.

[Differentiation of prostatitis and clinically significant prostate cancer in peripheral zone using the prostate imaging-reporting and data system]

Objective: To determine whether clinically significant prostate cancer (PCa) and prostatitis in the peripheral zone can be distinguished using prostate imaging reporting and data system version 1 (PI-RADS V1) and version 2(PI-RADS V2). Methods: Between September 2010 and August 2016, mpMRI data of 77 patients with PCa and 29 prostatitis obtained at 3.0 T were collected in Zhangjiagang Hospital Affiliated to Soochow University. Every lesion was scored according to PI-RADS (V1 and V2), as well as a sum score and a PI-RADS V2 score. The non-parametric Kruskal-Wallis test was used to assess differences between PCa and prostatitis regarding PS3, PS4 and PI-RADS V2 score. The diagnostic performance of PI-RADS V1 and V2 for detection of prostatitis in peripheral zone was compared by analyzing ROC curve. Results: The PI-RADS V1 score for PS3, PS4 and the PI-RADS V2-score were all significantly higher for PCa (PS3:12.1±2.1; PS4:16.2±2.9; V2:4.6±0.8) than for prostatitis (PS3:8.0±0.7; PS4:10.6±1.0; V2:3.0±0.5) (all P<0.01). Of these parameters, PS4 achieved the highest predictive value for the presence of prostatitis with an AUC of 0.937, sensitivity and specificity were 87.0%, 97.0% with a threshold of 12.5. Conclusion: Prostatitis can be differentiated from clinically significant PCa in peripheral zone on mpMRI using PI-RADS system, PS4 achieved better results compared to PS3 and V2.

Expressing Arsenite Antiporter PvACR3;1 in Rice (Oryza sativa L.) Decreases Inorganic Arsenic Content in Rice Grains

Rice (Oryza sativa) is a major food crop in the world, feeding half of the world's population. However, rice is efficient in taking up toxic metalloid arsenic (As), adversely impacting human health. Among different As species, inorganic As is more toxic than organic As. Thus, it is important to decrease inorganic As in rice to reduce human exposure from the food chain. The arsenite (AsIII) antiporter gene PvACR3;1 from As-hyperaccumulator Pteris vittata decreases shoot As accumulation when heterologously expressed in plants. In this study, three homozygous transgenic lines (L2, L4, and L7) of T3 generation were obtained after transforming PvACR3;1 into rice. At 5 μM of AsIII, PvACR3;1 transgenic rice accumulated 127%-205% higher As in the roots, with lower As translocation than wild type (WT) plants. In addition, at 20 μM of AsV, the transgenic rice showed similar results, indicating that expressing PvACR3;1 increased As retention in the roots from both AsIII and AsV. Furthermore, PvACR3;1 transgenic rice plants were grown in As-contaminated soils under flooded conditions. PvACR3;1 decreased As accumulations in transgenic rice shoots by 72%-83% without impacting nutrient minerals (Mn, Zn, and Cu). In addition, not only total As in unhusked rice grain of PvACR3;1 transgenic lines were decreased by 28%-39%, but also inorganic As was 26%-46% lower. Taken together, the results showed that expressing PvACR3;1 effectively decreased both total As and inorganic As in rice grain, which is of significance to breed low-As rice for food safety and human health.

Effect of length of apical root resection on the biomechanical response of a maxillary central incisor in various occlusal relationships

AIM

To investigate the stress distribution and tooth displacement of a maxillary central incisor with various apical root resection lengths and occlusal relationships using finite element (FE) analysis.

METHODOLOGY

A maxillary central incisor was scanned by micro-CT. First, the FE intact incisor model with dentine, enamel, pulp and root surrounded by alveolar bone and periodontal ligament was designed based on the micro-CT image data. Then, six FE models with varying lengths of apical root resection were established to simulate the clinical treatment and reveal the clinically applicable limit of apical root resection during endodontic microsurgery. For each model under different loading conditions, the maximum von Mises stress (σ max) at the root apex, root cervix, alveolar bone and periodontal ligament and the maximum tooth displacement (ΔR max) were calculated and compared.

RESULTS

In a normal occlusion, more than 6 mm of root resection resulted in a marked increase in the ΔR max values (>10%) and σ max values of alveolar bone (>50%); the stress levels at the root apex increased dramatically when the apical root was resected more than 7 mm. With increased overjet, apical root resection did not change the stress level markedly until it reached 8 mm, but the ΔR max increased markedly (>10%) if the root was resected more than 5 mm. With deep overbites, the σ max increased significantly (>50%) when the root was resected more than 4 mm whilst the ΔR max decreased. With increased overjet and deep overbite, more than 6 mm of resection resulted in a substantial σ max increase (>50%) of alveolar bone and the ΔR max increased markedly (>10%) when the root was resected 8 mm. Additionally, the σ max and the ΔR max values were greater with increased overjet and lower with deep overbites.

CONCLUSIONS

Using FE analysis, apical root resection of more than 6 mm resulted in a marked increase of stress distribution and tooth displacement in normal and increased overjet with deep overbite occlusal relationships. In increased overjets or deep overbites, more than 5 mm or 4 mm, respectively, stress distribution and tooth displacement increased markedly.

Multichannel continuous-wave fiber cavity ringdown gas sensing utilizing frequency-shifted interferometry

We present a multichannel continuous-wave (CW) fiber cavity ringdown (FCRD) gas sensing method based on frequency-shifted interferometry (FSI). This scheme detects gas concentration by measuring the intensity decay rates of continuous light from different ringdown cavities in the spatial domain, unlike conventional FCRD techniques, which measure the decay rates of pulse light in the time domain. This method shares one CW light source, one slow detector, and one slow data collector. In order to illustrate the theory, acetylene gas concentration measurement in a two-channel FSI-FCRD system was experimentally conducted in the range of 0%-1%. A linear relation was established between concentration and absorption loss, which is proportional to the intensity decay rate, and the measurement resolutions of 3.871%/dB and 3.658%/dB were achieved, respectively. The results reveal that the proposed system has the advantages of low cost, high sensitivity, high precision, and good stability in multichannel gas detection.

[Internal carotid artery aneurysms with the initial symptom of epistaxis: a case report]

The patient has complained of twice left nose bleeding. Nasal endoscope examination found bloodstain in recessus sphenoethmoidalis, while nasal sinuses MR examination showed moderate and slightly high signal in left sphenoid sinus on T₁WI and T₂WI. Then, she was underwent nasal endoscopic surgery to stop bleeding. A dark red, pulsating tissue was found above the lateral wall of the sphenoid sinus during the surgery. After the surgery, the patient did a cerebral digital vascular angiography and the diagnosis was internal carotid artery aneurysms rupture.

Complete Stability Analysis With Respect to Delay for Neural Networks

The stability property of delayed neural networks (NNs) along the whole delay axis is studied in this paper. Such a complete stability problem with respect to the delay parameter has not been addressed in the community of NNs. Most of the existing studies focus on the stability interval of delay starting from zero and are not applicable for the complete stability problem. In this paper, we will present some examples to show that there are various types of stability intervals for NNs, demonstrating the necessity of the complete stability analysis. We will adopt a frequency-sweeping approach to study delayed NNs in this paper. As a result, the complete stability problem with respect to delay for NNs can be systematically solved. The approach is applicable in the general case and simple to implement. Finally, some representative examples illustrate the approach.

Phosphate Transporter PvPht1;2 Enhances Phosphorus Accumulation and Plant Growth without Impacting Arsenic Uptake in Plants

Phosphorus is an important macronutrient for plant growth and is acquired by plants mainly as phosphate (P). Phosphate transporters (Phts) are responsible for P and arsenate (AsV) uptake in plants including arsenic-hyperaccumulator Pteris vittata. P. vittata is efficient in AsV uptake and P utilization, but the molecular mechanism of its P uptake is largely unknown. In this study, a P. vittata Pht, PvPht1;2, was cloned and transformed into tobacco ( Nicotiana tabacum). In hydroponic experiments, all transgenic lines displayed markedly higher P content and better growth than wild type, suggesting that PvPht1;2 mediated P uptake in plants. In addition, expressing PvPht1;2 also increased the shoot/root ³²P ratio by 69-92% and enhanced xylem sap P by 46-62%, indicating that PvPht1;2 also mediated P translocation in plants. Unlike many Phts permeable to AsV, PvPht1;2 showed little ability to transport AsV. In soil experiments, PvPht1;2 also significantly increased shoot biomass without elevating As accumulation in PvPht1;2 transgenic tobacco. Taken together, our results demonstrated that PvPht1;2 is a specific P transporter responsible for P acquisition and translocation in plants. We envisioned that PvPht1;2 can enhance crop P acquisition without impacting AsV uptake, thereby increasing crop production without compromising food safety.

Second-harmonic imaging microscopy for identifying colorectal intraepithelial neoplasia

In this study, second-harmonic imaging microscopy was used to monitor precancerous colorectal lesions at different stages. It was found that the morphology of glands and lamina propria in mucosa changes with the progression of colorectal diseases from normal to low-grade intraepithelial neoplasia to high-grade intraepithelial neoplasia and this microscopy has the ability of direct visualization of these warning symptoms. Furthermore, two morphologic variables were quantified to determine the changes of glands and collagen in lamina propria during the development of colorectal intraepithelial neoplasia. These results suggest that second-harmonic imaging microscopy has the potential in label-freely and effectively distinguishing between normal and precancerous colorectal tissues, and will be helpful for early diagnosis and treatment of colorectal diseases.

Label-free identification of the microstructure of rat spinal cords based on nonlinear optical microscopy

The spinal cord is a vital link between the brain and the body and mainly comprises neurons, glial cells and nerve fibres. In this work, nonlinear optical (NLO) microscopy based on intrinsic tissue properties was employed to label-freely analyze the cells and matrix in spinal cords at a molecular level. The high-resolution and high-contrast NLO images of unstained spinal cords demonstrate that NLO microscopy has the ability to show the microstructure of white and grey matter including ventral horn, intermediate area, dorsal horns, ventral column, lateral column and dorsal column. Neurons with various sizes were identified in grey matter by dark spots of nonfluorescent nuclei encircled by cytoplasm-emitting two-photon excited fluorescence signals. Nerve fibres and neuroglias were observed in white matter. Besides, the spinal arteries were clearly presented by NLO microscopy. Using spectral and morphological information, this technique was proved to be an effective tool for label-freely imaging spinal cord tissues, based on endogenous signals in biological tissue. With future development, we foresee promising applications of the NLO technique for in vivo, real-time assessment of spinal cord diseases or injures.

Measurement and simulation of the response function of time of flight enhanced diagnostics neutron spectrometer for beam ion studies at EAST tokamak

The 2.5 MeV TOFED (Time-Of-Flight Enhanced Diagnostics) neutron spectrometer with a double-ring structure has been installed at Experimental Advanced Superconducting Tokamak (EAST) to perform advanced neutron emission spectroscopy diagnosis of deuterium plasmas. This work describes the response function of the TOFED spectrometer, which is evaluated for the fully assembled instrument in its final layout. Results from Monte Carlo simulations and dedicated experiments with pulsed light sources are presented and used to determine properties of light transport from the scintillator. A GEANT4 model of the TOFED spectrometer was developed to calculate the instrument response matrix. The simulated TOFED response function was successfully benchmarked against measurements of the time-of-flight spectra for quasi-monoenergetic neutrons in the energy range of 1-4 MeV. The results are discussed in relation to the capability of TOFED to perform beam ion studies on EAST.

Label-free detection of fibrillar collagen deposition associated with vascular elements in glioblastoma multiforme by using multiphoton microscopy

Glioblastoma multiforme (GBM-WHO grade IV) is the most common and the most aggressive form of brain tumors in adults with the median survival of 10-12 months. The diagnostic detection of extracellular matrix (ECM) component in the tumour microenvironment is of prognostic value. In this paper, the fibrillar collagen deposition associated with vascular elements in GBM were investigated in the fresh specimens and unstained histological slices by using multiphoton microscopy (MPM) based on two-photon excited fluorescence (TPEF) and second harmonic generation (SHG). Our study revealed the existence of fibrillar collagen deposition in the adventitia of remodelled large blood vessels and in glomeruloid vascular structures in GBM. The degree of fibrillar collagen deposition can be quantitatively evaluated by measuring the adventitial thickness of blood vessels or calculating the ratio of SHG pixel to the whole pixel of glomeruloid vascular structure in MPM images. These results indicated that MPM can not only be employed to perform a retrospective study in unstained histological slices but also has the potential to apply for in vivo brain imaging to understand correlations between malignancy of gliomas and fibrillar collagen deposition.

Involvement of oxidative stress in tri-ortho-cresyl phosphate-induced liver injury in male mice

Tri-ortho-cresyl phosphate (TOCP) has been widely used as plasticizers, plastic softeners, and flame retardants in industry and reported to have delayed neurotoxicity and reproductive toxicology in animals. However, it remains to be elusive whether TOCP induces liver injury. In this study, male mice were orally administered different concentrations of TOCP (100, 200, or 400 mg/kg/day) for 28 days. Histological examination showed that TOCP led to serious hepatocellular injury. In addition, administration of TOCP induced a marked elevation in the serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels in mice. The content of malondialdehyde (MDA) was increased significantly in the liver after the mice were treated with TOCP; while there was a dramatic decrease in the content of glutathione (GSH) and the activities of antioxidative enzymes superoxide dismutase (SOD) and glutathione peroxidase (GSH-PX). TOCP inhibited viability of mouse liver cancer Hepa 1-6 cells in a dose-dependent manner. Meanwhile, TOCP significantly increased MDA content and inhibited GSH content and the activities of SOD and GSH-PX in the cells, respectively. Oxidative stress dramatically inhibited viability of Hepa 1-6 cells; while inhibition of oxidative stress by N-acetyl-l-cysteine could rescue the cell viability inhibited by TOCP to a certain extent. In summary, oxidative stress might be involved in TOCP-induced hepatocellular injury in male mice.

Effect of TIMP1 transfection on PTEN expression in human kidney proximal tubular cells

To explore the role of metalloproteinase-1 (TIMP-1) tissue inhibitor in the mechanisms of kidney aging, we observed the effects of sense and antisense transfection of TIMP-1 and of metalloproteinase (MMP) inhibitors on phosphatase and tensin homolog (PTEN), vascular endothelial growth factor (VEGF), and Flk-1 expression in TIMP-1 transgenic human proximal tubular epithelial cells (HKCs). Transfected HKCs were co-incubated with 100 μM MMP-2 and MMP-9 inhibitor III for 24 h to affect enzyme inhibition. TIMP-1, MMP-2, MMP-9, PTEN, VEGF, and Flk-1 mRNA expression was detected by reverse transcription-polymerase chain reaction. PTEN, VEGF, and Flk-1 protein expression in cells of each experimental group was measured by indirect immunofluorescence. We found that PTEN expression was up-regulated (P < 0.05) in the sense TIMP-1-transfected group (P < 0.05) compared with the non-transfected and empty vector groups, and that expression of VEGF and Flk-1 was down-regulated (P < 0.05). In contrast, the antisense TIMP-1 transgenic group showed the opposite results (P < 0.05). No significant differences in expression of PTEN, VEGF, or Flk-1 were observed among the MMP- 2/MMP-9 inhibitor III, non-transfected, and empty vector groups (P > 0.05). These results suggest that in the progression of renal aging, high expression of TIMP-1 up-regulates PTEN expression through an MMP-independent pathway, and subsequently down-regulates the expression of VEGF and Flk-1, indicating that PTEN and TIMP-1 are involved in the aging-associated impairment of renal angiogenesis. Our study provides a theoretical basis for further exploration of the mechanism underlying TIMP- 1 participation in renal aging progression.

Chemotherapy combined with target drugs in the treatment of advanced colorectal cancer: a meta-analysis based on Chinese patients

BACKGROUND

Colorectal carcinoma is one of most diagnosed solid malignant carcinoma. The chemotherapy combined with target drugs in the treatment of advanced colorectal cancer in not conclusive.

METHODS

The clinical studies reporting the activity and adverse events between chemotherapy alone versus chemotherapy combined with anti-epidermal growth factor receptor drugs were screened in the databases of Medline, the Cochrane Library, Wanfang and CNKI and included in this meta-analysis. The risk ratio (RR) and its 95% confidence interval (CI) for treatment response and adverse events were pooled by random or fixed effect model.

RESULTS

A total of 10 clinical studies reporting chemotherapy combined with the target in the treatment of advanced colorectal cancer were included in this study. The pooled RR was 3.26 (95% CI: 1.74-6.11, P < 0.05), 1.49 (95% CI: 1.23-1.80) and 1.65 (95% CI: 1.37-1.98) for complete response (CR), partial response and objective response rate, respectively. For nausea and vomiting events, the RR was 1.62 (95% CI: 1.33-1.97, P < 0.05) indicating higher incidence of nausea and vomiting was observed in the combined group compared with chemotherapy alone. However, the diarrhea (RR = 1.10, 95% CI: 0.86-1.42, P > 0.05), liver function damage (RR = 1.03, 95% CI: 0.74-1.42), myelosuppression (RR = 1.04, 95% CI: 0.83-1.31) and neurotoxicity (RR = 1.12, 95% CI: 0.93-1.35) were not different between the two groups.

CONCLUSION

For Chinese patients with advanced colorectal cancer, chemotherapy combined with target drug can improve the response rate, but also increase the risk of nausea and vomiting.

Differentiating the extent of cartilage repair in rabbit ears using nonlinear optical microscopy

Nonlinear optical microscopy (NLOM) was used as a noninvasive and label-free tool to detect and quantify the extent of the cartilage recovery. Two cartilage injury models were established in the outer ears of rabbits that created a different extent of cartilage recovery based on the presence or absence of the perichondrium. High-resolution NLOM images were used to measure cartilage repair, specifically through spectral analysis and image texture. In contrast to a wound lacking a perichondrium, wounds with intact perichondria demonstrated significantly larger TPEF signals from cells and matrix, coarser texture indicating the more deposition of type I collagen. Spectral analysis of cells and matrix can reveal the matrix properties and cell growth. In addition, texture analysis of NLOM images showed significant differences in the distribution of cells and matrix of repaired tissues with or without perichondrium. Specifically, the decay length of autocorrelation coefficient based on TPEF images is 11.2 ± 1.1 in Wound 2 (with perichondrium) and 7.5 ± 2.0 in Wound 1 (without perichondrium), indicating coarser image texture and faster growth of cells in repaired tissues with perichondrium (p < 0.05). Moreover, the decay length of autocorrelation coefficient based on collagen SHG images also showed significant difference between Wound 2 and 1 (16.2 ± 1.2 vs. 12.2 ± 2.1, p < 0.05), indicating coarser image texture and faster deposition of collagen in repaired tissues with perichondrium (Wound 2). These findings suggest that NLOM is an ideal tool for studying cartilage repair, with potential applications in clinical medicine. NLOM can capture macromolecular details and distinguish between different extents of cartilage repair without the need for labelling agents.

Down-regulation of miR-1246 in cervical cancer tissues and its clinical significance

OBJECTIVE

MicroRNAs (miRNAs) are non-coding RNAs that regulate the expression of mRNAs by binding to their 3'-untranslated regions (UTRs). Accumulating evidences show that miRNAs are involved in tumorigenesis such as lung cancer, liver cancer, colon cancer, and cervical cancer. In this study, we focused on the expression of miR-1246 in clinical cervical cancer tissues as well as the relationship between miR-1246 and HPV16E6 infection status.

METHODS

Real-time quantitative polymerase chain reaction technology was used to detect the expression of miR-1246 in 68 cervical cancer tissues and 52 normal tissues. The expression of miR-1246 also was tested in HPV16E6 negative cervical cell line (SiHa) or HPV16E6 positive cell line (C33A). Western blot was performed to detect the expression of DYRK1A after knocking down HPV16E6.

RESULTS

Our data showed that the expression of miR-1246 was dramatically decreased in cervical cancer tissue, compared with normal control group (p=0.0012), and miR-1246 was negatively correlated with clinical stage and HPV16E6 infected status (p=0.0410), but no correlation was observed with age, tumor diameter, cervical invasion depth, lymph node metastasis, or vascular invasion (p>0.05). Knock down of HPV16E6 significantly raised DYRK1A protein expression targeted by miR-1246.

CONCLUSIONS

The expression of miR-1246 is negatively correlated with cervical cancer procedure as well as HPV16E6 infection status and the miR-1246 may act as a diagnostic biomarker for cervical cancer. In addition, HPV16E6 infection may be a major reason leading to decrease the expression of miR-1246 in cervical cancer. This finding contributes to deep understanding of the miR-1246 function in cervical carcinogenesis.

Reactive metabolite activation by CYP2C19-mediated rhein hepatotoxicity

1. Rhein, an active ingredient in the root of rhubarb, is used for its beneficial effects in a variety of clinical applications including the treatment of osteoarthritis and diabetic nephropathy. However, its hepatotoxicity has been reported in recent years. Rhein belongs to the conjugate structure which could be activated to reactive metabolites (RMs) inducing side-effects. This study is to explore the relationship between RMs and hepatotoxicity. 2. Based on the early detection of RMs, we have established a series of key technologies to research rhein hepatotoxicity mechanism: IC50 shift experiments and reduced glutathione (GSH) trapping experiment are adopted to identify RMs. The model of low activity of CYP450 enzymes (CYPs) in primary rat hepatocyte is constructed to analyze the relationship between the primary metabolic enzyme and hepatotoxicity of rhein better. 3. The IC50 shift value for CYP2C19 is 1.989, it suggests that CYP2C19 could activate rhein to RM. The structure of RM is epoxide intermediate. Besides, it is found that CYP2C19 is a primary metabolic enzyme for rhein. In the cytotoxicity assay, it is reported that rhein could cause mitochondrial dysfunction. Furthermore, mitochondrial membrane potential (Δψm) and AST levels could be restored by adding inhibitor of CYP2C19 together with rhein, which further shows that CYP2C19 could mediate the hepatotoxicity of rhein. 4. We put forward the possible mechanism that reactive metabolite activation by CYP2C19 mediated rhein hepatotoxicity, it provides important information on predicting in vivo drug-induced liver injury (DILI).

Design of the radiation shielding for the time of flight enhanced diagnostics neutron spectrometer at Experimental Advanced Superconducting Tokamak

A radiation shielding has been designed to reduce scattered neutrons and background gamma-rays for the new double-ring Time Of Flight Enhanced Diagnostics (TOFED). The shielding was designed based on simulation with the Monte Carlo code MCNP5. Dedicated model of the EAST tokamak has been developed together with the emission neutron source profile and spectrum; the latter were simulated with the Nubeam and GENESIS codes. Significant reduction of background radiation at the detector can be achieved and this satisfies the requirement of TOFED. The intensities of the scattered and direct neutrons in the line of sight of the TOFED neutron spectrometer at EAST are studied for future data interpretation.

Light output function and assembly of the time-of-flight enhanced diagnostics neutron spectrometer plastic scintillators for background reduction by double kinematic selection at EAST

The 2.5 MeV neutron spectrometer TOFED (Time-Of-Flight Enhanced Diagnostics) has been constructed to perform advanced neutron emission spectroscopy diagnosis of deuterium plasmas on EAST. The instrument has a double-ring structure which, in combination with pulse shape digitization, allows for a dual kinematic selection in the time-of-flight/recoil proton energy (tof/Ep) space, thus improving the spectrometer capability to resolve fast ion signatures in the neutron spectrum, in principle up to a factor ≈100. The identification and separation of features from the energetic ions in the neutron spectrum depends on the detailed knowledge of the instrument response function, both in terms of the light output function of the scintillators and the effect of undesired multiple neutron scatterings in the instrument. This work presents the determination of the light output function of the TOFED plastic scintillator detectors and their geometrical assembly. Results from dedicated experiments with γ-ray sources and quasi-monoenergetic neutron beams are presented. Implications on the instrument capability to perform background suppression based on double kinematic selection are discussed.

Design of a magnetic shielding system for the time of flight enhanced diagnostics neutron spectrometer at Experimental Advanced Superconducting Tokamak

The novel neutron spectrometer TOFED (Time of Flight Enhanced Diagnostics), comprising 90 individual photomultiplier tubes coupled with 85 plastic scintillation detectors through light guides, has been constructed and installed at Experimental Advanced Superconducting Tokamak. A dedicated magnetic shielding system has been constructed for TOFED, and is designed to guarantee the normal operation of photomultiplier tubes in the stray magnetic field leaking from the tokamak device. Experimental measurements and numerical simulations carried out employing the finite element method are combined to optimize the design of the magnetic shielding system. The system allows detectors to work properly in an external magnetic field of 200 G.

Data acquisition system with pulse height capability for the TOFED time-of-flight neutron spectrometer

A new time-of-flight neutron spectrometer TOFED has been constructed for installation at Experimental Advanced Superconducting Tokamak. A data acquisition system combining measurements of flight time and energy from the interaction of neutrons with the TOFED scintillators has been developed. The data acquisition system can provide a digitizing resolution better than 1.5% (to be compared with the >10% resolution of the recoil particle energy in the plastic scintillators) and a time resolution <1 ns. At the same time, it is compatible with high count rate event recording, which is an essential feature to investigate phenomena occurring on time scales faster than the slowing down time (≈100 ms) of the beam ions in the plasma. Implications of these results on the TOFED capability to resolve fast ion signatures in the neutron spectrum from EAST plasmas are discussed.

Monte Carlo simulation of a Bonner sphere spectrometer for application to the determination of neutron field in the Experimental Advanced Superconducting Tokamak experimental hall

To assess the neutron energy spectra and the neutron dose for different positions around the Experimental Advanced Superconducting Tokamak (EAST) device, a Bonner Sphere Spectrometer (BSS) was developed at Peking University, with totally nine polyethylene spheres and a SP9 (3)He counter. The response functions of the BSS were calculated by the Monte Carlo codes MCNP and GEANT4 with dedicated models, and good agreement was found between these two codes. A feasibility study was carried out with a simulated neutron energy spectrum around EAST, and the simulated "experimental" result of each sphere was obtained by calculating the response with MCNP, which used the simulated neutron energy spectrum as the input spectrum. With the deconvolution of the "experimental" measurement, the neutron energy spectrum was retrieved and compared with the preset one. Good consistence was found which offers confidence for the application of the BSS system for dose and spectrum measurements around a fusion device.