Rational design and synthesis of triazene-amonafide derivatives as novel potential antitumor agents causing oxidative damage towards DNA through intercalation mode.

In this work, we rationally designed and synthesized two novel triazene-amonafide derivatives 2-(2-(diisopropylamino)ethyl)-5-(3,3-dimethyltriaz-1-en-1-yl)-1H-benzo[de]isoquinoline-1,3(2H)-dione (D-11) and 5-(3,3-diethyltriaz-1-en-1-yl)-2-(2-(diisopropylamino)ethyl)-1H-benzo[de]isoquinoline-1,3(2H)-dione (D-12) as potential antitumor agents. The DNA damage induced by the intercalation mode of D-11 (D-12) towards DNA was electrochemically detected through the construction of efficient biosensors. The consecutive processes of reversible redox of naphthylimide ring and irreversible oxidation of triazene moiety were elucidated on the surface of glassy carbon electrode (GCE) by CV, SWV, and DPV methods. Electrochemical biosensors were obtained through the immobilization of ctDNA, G-quadruplexes, poly(dG), and poly(dA), respectively, on the clean surface of GCE. After the incubation of biosensors with D-11 or D-12, the peaks of dGuo and dAdo decreased prominently, and the peak of 8-oxoGua appeared at +0.50 V, suggesting that the interaction between D-11 (D-12) and DNA could result in the oxidative damage of guanine. Unexpected, the as-prepared DNA biosensor possessed satisfactory anti-interference property and good practicability in real samples. UV-vis and fluorescence spectra, and gel electrophoresis assays were employed to further confirm the intercalation mode of D-11 (D-12) towards DNA base pairs. Moreover, D-11 was proved to exhibit stronger anti-proliferation activity than mitionafide and amonafide against both A549 and HeLa cell lines.

Age at first birth is associated with the likelihood of frailty in middle-aged and older women: A population-based analysis from NHANES 1999-2018.

OBJECTIVES: This study examined whether age at first birth (AFB) is associated with the prevalence of frailty in middle-aged and older women. METHODS: The study included 10,828 women (age ≥ 45 years) from the National Health and Nutrition Examination Survey (NHANES) (1999-2018) in the United States. AFB data were collected using a standardized reproductive health questionnaire. Frailty was measured using a 53-item frailty index and was diagnosed if the score on that index was over 0.21. Survey-weighted logistic regression models were used to assess the association between AFB and the prevalence of frailty. A survey-weighted restricted cubic spline (RCS) model was used to determine the dose-response relationship between AFB and frailty. Mediation analyses were performed to estimate the mediated effects of education levels, family poverty income ratio, and parity on the association between AFB and the likelihood of frailty. Finally, sensitivity and subgroup analyses were conducted to validate the robustness of our findings. RESULTS: Among the 10,828 women, 3828 (35.4 %) had frailty. The RCS depicted a U-shaped association between AFB and frailty. Compared with the women in the reference group (AFB: 33-35 years), women in the other groups (AFB: < 18, 18-20, 21-23, and 24-26 years) had a higher likelihood of frailty, with respective odds ratios (95 % confidence intervals) of 3.02 (1.89-4.83), 2.32 (1.54-3.50), 1.83 (1.19-2.81), and 1.64 (1.07-2.53). However, no statistically significant differences were detected for women with AFB of 27-29, 30-32, or > 35 years compared with the reference group. Education levels, family poverty income ratio, and parity significantly mediated the approximately linear negative association between AFB and frailty in the subset of women with AFB of ≤32 years and the mediation proportions were 23.4 %, 32.4 %, and 18.3 %, respectively (all p < 0.001). CONCLUSIONS: Based on our results, we conclude that early AFB is associated with a higher likelihood of frailty in middle-aged and older women.

Prediction of Long-Term Survival Outcome by Lymph Node Ratio in Patients of Parotid Gland Cancer: A Retrospective study.

Background: Lymph node ratio (LNR) has been reported to reliably predict cancer-specific survival (CSS) in parotid gland cancer (PGC). Our study was designed to validate the significance of LNR in patients with PGC. Methods: Patients diagnosed with stage I-IV PGC were enrolled from Surveillance Epidemiology and End Results database (SEER, N = 3529), which is the training group, and Sun Yat-sen University Cancer Center database (SYSUCC, N = 99), the validation group. We used X-tile software to choose the optimal cutoff value of LNR; then, univariable and multivariable analyses were performed, assessing the association between LNR and CSS. Results: The optimal cutoff value of LNR was 0.32 by X-tile based on 3529 patients from SEER. Cox proportional hazard regression analysis revealed better CSS for patients with LNR ≤ 0.32 (adjusted hazard ratio [HR] 1.612, 95% confidence interval [95% CI] 1.286-2.019; p < 0.001) compared with patients with LNR > 0.32 in SEER. In the SYSUCC cohort, patients with LNR ≤ 0.32 also had better CSS over patients with LNR > 0.32 (p < 0.001). In N2 and N3 stage groups, patients with LNR ≤ 0.32 had superior CSS outcomes over those with the LNR > 0.32 group, but this benefit was absent in the N1 stage group. Conclusions: In conclusion, the lymph node ratio turned out to be an independent prognostic factor for cancer-specific survival of PGC in this study. This valuable information could help clinicians to evaluate the prognosis of PGC and suggest that adequate lymph node dissection is necessary.

Synthesis of functional dicationic ionic liquids for the treatment of lignocellulosic biomass.

Mono-cationic ionic liquids (MILs) have been widely utilized for the treatment of lignocelluloses. However, the hydrophilic property of MILs increases the difficulty of isolating sugars and their reuse, which limits their industrial application. In the present study, a series of dicationic ionic liquids (DILs) were synthesized with totally different di-cations and di-anions. An alternating miscibility of DILs with water was observed depending on the dealing temperature. The functional DILs exhibiting hydrophobic and acidic properties were investigated for the treatment of corn stalk. High yields of sugars were achieved as 27.8% and 31.6% with DIL3 and DIL4, respectively. Cellulosic materials were obtained as 74.3% and 77.8% with DIL1 and DIL2 and 61.2% and 65.7% with DIL3 and DIL4, respectively. Enzymatic reaction was successfully performed with cellulosic materials after the DIL treatment. DILs were recycled and reused with no significant reduction in sugar yields. Hydrophobic DILs are a potentially effective approach to enable the successful decomposition and degradation of lignocellulosic biomass.

Synthesis of novel functional ionic liquids and their application in biomass.

A series of dicationic ionic liquids (ILs) including [PF6][(PYR)C4(MIM)][Cl], [PF6][(PYR)C4(PYR)][Cl], [PF6][(PYR)C5(MIM)][Cl], and [PF6][(PYR)C5(PYR)][Cl], and monocationic ILs including [(PYR)C4Cl][PF6], [(PYR)C5Cl][PF6], [(MIM)C2COOH][PF6] and [(PYR)C2COOH][PF6] were synthesized. Their thermal stability and melting points were determined. Their solubility with organic solvents and the miscibility with water were investigated. These functional ILs are hydrophilic at high temperatures and they are hydrophobic at low temperatures, which enable the effective isolation of the resulting reducing sugar. High yields of reducing sugar were obtained for corn stalk after 8 h (20.73%) and potato starch after 6 h (72.50%) by the treatment with the mixture of [PF6][(PYR)C4(PYR)][Cl] and [(PYR)C2COOH][PF6]. The reuse of dicationic and monocationic ILs was successfully performed and no significant reduction in yields of reducing sugar was observed. These functional ILs have important implications in the design of homogeneous and heterogeneous systems with water and organic solvents, which could be used to satisfy some specific applications.

[Role of endoplasmic reticulum stress-induced apoptosis of trophoblasts in intrahepatic cholestasis during pregnancy].

OBJECTIVE: To investigate the role of endoplasmic reticulum stress (ERS)-induced trophoblast apoptosis in the development of intrahepatic cholestasis during pregnancy (ICP). METHODS: Twenty pregnant women with ICP and 20 normal pregnant women undergoing cesarean section were enrolled in this study. The number of placenta syncytial knots in these women was determined using HE staining. The mRNA expressions of GRP78, CHOP, caspase-3, and caspase-7 were detected using RT-PCR in the placental tissues of the women and also in HTR-8/SVneo cells treated with different doses of deoxycholic acid (DCA). Caspase-3 and caspase-7 activities were also detected in DCA-treated HTR-8/SVneo cells using commercial assay kits, and the presence of apoptotic bodies in the cells were detected with electron microscopy. RESULTS: Compared with normal placental tissues, the placenta from women with ICP showed significantly increased syncytial knots (P<0.01) and obviously enhanced mRNA expressions of GRP78, CHOP, caspase-3, and caspase-7 (P<0.05). In HTR-8/SVneo cells treated with different doses of DCA (0, 10, 50, and 100 µmol/L), the mRNA expressions of GRP78, CHOP, caspase-3 and caspase-7 were significantly increased in a dose-dependent manner (P<0.05) and the protein levels of GRP78 and CHOP were also increased dose-dependently. Treatment with DCA at 50 µmol/L for 24 h significantly upregulated caspase-3 and caspase-7 activity in the cells (P<0.05), and the cells treated with 50 µmol/L DCA for 12 h showed the presence of apoptotic bodies. CONCLUSION: The activation of ERS and enhanced apoptosis of the trophoblasts occur in the placenta of women with ICP. DCA can significantly increase the expressions of ERS markers and thus lead to trophoblast apoptosis, suggesting that ERS-induced trophoblasts apoptosis may play a key role in the development of ICP.

Screening of potential IL-tolerant cellulases and their efficient saccharification of IL-pretreated lignocelluloses.

Lignocellulosic biomass as one of the most abundant and renewable resources has great potential for biofuel production. The complete conversion of biomass to biofuel is achieved through the effective pretreatment process and the following enzyme saccharification. Ionic liquids (ILs) are considered as a green solvent for lignocellulose pretreatment. However, ILs exhibit an inhibitory effect on cellulase activity, leading to a subsequent decrease in the efficiency of saccharification. The screening of new potential IL-tolerant cellulases is important. In the current study, a fungal strain with a relatively high cellulase production was isolated and identified as Penicillium oxalicum HC6. The culture conditions were optimized using corn stover and peptone as the carbon source and nitrogen source at pH 4.0 and 30 °C with an inoculation size of 2% (v/v) for 8 days. It was found that P. oxalicum HC6 exhibited potential salt tolerance with the increase of the enzyme production at a salt concentration of 5.0% (w/v). In addition, high enzyme activities were obtained at pH 4.0-6.0 and 50-65 °C. The crude enzyme from P. oxalicum HC6 with good thermal stability was also stable in the presence of salt and ILs. Good yields of reducing sugar were obtained by the crude enzyme from P. oxalicum HC6 after the saccharification of corn stover that was pretreated by ILs. P. oxalicum HC6 with potentially salt-tolerant and IL-tolerant enzymes has great potential application in the enzymatic saccharification of lignocellulose.

[Expectant therapy versus curettage for retained products of conception after second trimester termination of pregnancy: analysis of outcomes and complications].

OBJECTIVE: To evaluate the prognosis and complications of expectant therapy and curettage for retained product of conception (RPOC) after second trimester termination of pregnancy (TOP). METHODS: A total of 270 patients with RPOC following second trimester TOP in Nanfang Hospital between January, 2014 and December, 2015 were included in this study. The duration of vaginal bleeding time and menstruation recovery interval were compared between patients receiving expectant therapy and curettage for RPOC, and binary logistic regression was used to assess the risk factors for complications in bivariate and multivariate analyses. RESULTS: The duration of vaginal bleeding time was significantly longer in expectant therapy group than in curettage group (P=0.005), while the menstruation recovery interval did not differ significantly between the two groups. The incidence of vaginal bleeding time for over 42 days was significantly higher in curettage group than in expectant therapy group (P=0.040), and the incidence of a menstruation recovery interval beyond 60 days was comparable between them. The incidence of complications was significantly higher in curettage group than in expectant therapy group either with adjustment of age, gravidity, parity, history of uterine surgery status, gestational age, type of indications, regimens for TOP and induction-abortion interval (OR=18.26 [95% CI: 3.57-93.42], P<0.001) or without adjustment (OR=10.60, [95% CI: 2.36-47.66], P=0.002). CONCLUSION: Expectant therapy and curettage for RPOC after second trimester TOP have comparable prognosis, but curettage is associated with a significantly higher rate of complications.

Preterm Birth and Subsequent Risk of Acute Childhood Leukemia: a Meta-Analysis of Observational Studies.

BACKGROUND: Preterm birth (PTB) has been recognized as a crucial long term risk factor for multiple non-communicable diseases. However, studies between the relationship of PTB and the risk of acute childhood leukemia have yielded inconclusive results. Therefore, we performed a meta-analysis to systematically review the current literature to investigate whether PTB is associated with increased risk of acute childhood leukemia. METHODS: Three electronic databases (PubMed, Web of Science, and EMBASE) were searched up to December 1st, 2015. Relevant studies reporting the association between PTB and subsequent risk of acute childhood leukemia were included for further evaluation. Statistical analysis was performed using Revmen 5.3 and Stata 10.0. RESULTS: A total of 12 studies for acute childhood leukemia, eight studies for acute lymphoblastic leukemia (ALL), and seven studies for acute myeloid leukemia (AML) were included in the current meta-analyses. We calculated pooled odds ratio (OR) and 95% confidence interval (CI) to evaluate the relationship between PTB and acute childhood leukemia as well as its two subtypes: ALL and AML. Our results suggested that PTB was significantly associated with increased risk of acute childhood leukemia (OR = 1.09, 95% CI = 1.02-1.17, P = 0.01) and AML (OR = 1.42, 95% CI = 1.21-1.67, P < 0.01). However, PTB was not significantly associated with an increased risk of ALL (OR = 1.04, 95% CI = 0.96-1.13, P = 0.29). CONCLUSION: Our data showed that PTB increased the risk of AML. Further studies are required to explore causality and dissect the biological mechanisms involved.

Maternal HCV infection is associated with intrauterine fetal growth disturbance: A meta-analysis of observational studies.

Since the evidence regarding the association between maternal hepatitis C virus (HCV) infection and impaired intrauterine fetal growth had not been conclusive, the aim of the present study was to evaluate the risk of maternal HCV infection in association with intrauterine fetal growth restriction (IUGR) and/or low birth weight infants (LBW). We performed an extensive literature search of PubMed, MEDLINE, and EMBASE through December 1, 2015. The odds ratios (ORs) of HCV infection and IUGR/LBW were calculated and reported with 95% confidence intervals (95% CIs). Statistical analysis was performed using RevMen 5.3 and Stata 10.0. Seven studies involving 4,185,414 participants and 5094 HCV infection cases were included. Significant associations between HCV infection and IUGR (OR = 1.53, 95% CI: 1.40-1.68, fixed effect model) as well as LBW were observed (OR = 1.97, 95% CI: 1.43-2.71, random effect model). The results still indicated consistencies after adjusting for multiple risk factors which could affect fetal growth, including maternal age, parity, maternal smoking, alcohol abuse, drugs abuse, coinfected with HBV/HIV and preeclampsia. Our findings suggested that maternal HCV infection was significantly associated with an increased risk of impaired intrauterine fetal growth. In clinical practice, a closer monitoring of intrauterine fetal growth by a series of ultrasound might be necessary for HCV-infected pregnant population.

Can HPV vaccine have other health benefits more than cancer prevention? A systematic review of association between cervical HPV infection and preterm birth.

Although the association between high-risk human papillomavirus (HPV) infection and cervical dysplasia as well as cervical cancer is well established, studies on the relationship between HPV infection and risk of preterm birth (PTB) have yielded inconclusive and inconsistent results. Therefore, we conducted a meta-analysis to investigate the association between HPV infection and PTB. The electronic database was searched until July 1, 2014. Relevant studies reporting the association between HPV infection and the risk of PTB were included and for further evaluation. Statistical analysis was performed using Revmen 5.3 and Stata 10.0. Six observational cohort studies and 2 case-control studies were included. A significant association between HPV infection and PTB was observed (odds ratio=2.12, 95% CI 1.51-2.98, P<0.001, random effect model). Stratification according to diagnostic methods indicated that both positive HPV DNA status and abnormal cervical cytology were associated with increased risk of PTB. Moreover, our data suggested a higher risk of PTB in Caucasian HPV-infected population, while no significant association was observed in the Asian population. Although the causality remains unclear, findings from our meta-analysis indicate that HPV infection might increase the risk of PTB. In the future, prospective cohorts with larger samples sizes are warranted to ascertain the causality and pathophysiological studies are required to explore the possible biological mechanisms involved.

Notch-1 and Ki-67 receptor as predictors for the recurrence and prognosis of Kimura's disease.

Kimura's disease (KD) is a rare chronic disease with unknown origin. It remains controversial in KD's diagnosis, treatment, transformation and need further research. The aim of this study is to investigate the clinicopathologic features of KD and the relationship between the expression of Notch-1, Ki-67 receptor and the recurrence of KD. The hematoxylin and eosin sections and clinical data of 40 patients diagnosed with KD were examined retrospectively. Specimens were available in these 40 cases. Notch-1 and Ki-67 expression were examined using IHC (immunohistochemistry staining) analysis. Of 40 cases of KD (average age, 38.4 years; median age, 36.0 years), 34 cases (85.0%) were clinically seen to involve swelling of the head and neck region. Notch-1 and Ki-67 have a high expression in recurrent patients. High expression of Notch-1 receptor and Ki-67 tended to be found in patients who relapsed. This is the first study to discuss the correlation among Notch-1, Ki-67 and recurrent KD. These results suggest both of the markers may act as promising predictors for the recurrence and prognosis of KD. However, Notch-1 immunoexpression had no statistically significant association with the Ki-67 proliferation index.

Direct electrochemistry of glucose oxidase and glucose biosensing on a hydroxyl fullerenes modified glassy carbon electrode.

Direct electrochemistry of glucose oxidase (GOD) was achieved when GOD-hydroxyl fullerenes (HFs) nano-complex was immobilized on a glassy carbon (GC) electrode and protected with a chitosan (Chit) membrane. The ultraviolet-visible absorption spectrometry (UV-vis), transmission electron microscopy (TEM), and circular dichroism spectropolarimeter (CD) methods were utilized for additional characterization of the GOD, GOD-HFs and Chit/GOD-HFs. Chit/HFs may preserve the secondary structure and catalytic properties of GOD. The cyclic voltammograms (CVs) of the modified GC electrode showed a pair of well-defined quasi-reversible redox peaks with the formal potential (E°') of 353 ± 2 mV versus Ag/AgCl at a scan rate of 0.05 V/s. The heterogeneous electron transfer constant (ks) was calculated to be 2.7 ± 0.2s(-1). The modified electrode response to glucose was linear in the concentrations ranging from 0.05 to 1.0mM, with a detection limit of 5 ± 1 µM. The apparent Michaelis-Menten constant (Km(app)) was 694 ± 8 µM. Thus, the modified electrode could be applied as a third generation biosensor for glucose with high sensitivity, selectivity and low detection limit.

Direct electron transfer of horseradish peroxidase on a functional nanocomplex modified glassy carbon electrode.

Direct electron transfer of horseradish peroxidase (HRP) was achieved by immobilizing HRP on a functional nanocomplex modified glassy carbon (GC) electrode. The cyclic voltammograms (CVs) of the modified electrode have a pair of well-defined redox peaks with a formal potential (E°') of -26 ± 2 mV versus Ag/AgCl, in 0.05 M, pH7.0 phosphate buffer solution (PBS) at a scan rate of 0.05 V/s. The heterogeneous electron transfer constant (ks) was calculated to be 1.94 s-1. The modified electrode response toward hydrogen peroxide was linear in the concentrations ranging from 0.28 µM to 10 µM, with a detection limit of 0.28 µM. The apparent Michaelis-Menten constant (Kmapp) for H2O2 was 2.54 µM. Moreover, results of biochemical computation showed that the amino acid residues (Ala34, Arg38, Ser73, Arg75, Ala140, Pro141, Phe172, Gly173, Lys174, Phe179, Arg31, Ser35, Lys174, Gln176) of HRP may playa crucial role in the improvement of electron transport between electro-active site (heme group) of an HRP molecule and nanocomplex modified GC electrode.

[Diagnostic value of radom spot albuminuria to creatinine ratio in women with preeclampsia].

OBJECTIVE: To investigate the correlation between spot albuminuria to creatinine ratio (ACR) and 24 h urinary protein excretion in women with preeclampsia and determine the optimal cut-off values of spot ACR in mild preeclampsia and severe preeclampsia. METHODS: Twenty-eight women with mild preeclampsia and 22 with severe preeclampsia at Nanfang Hospital, Southern Medical University between October 2010 and June 2011 were recruited. Maternal serum cystatin, uric acid, urea nitrogen, creatinine and albumin levels were collected and analyzed. Twenty-four hours urinary protein excretion was measured with immunoturbidimetric assay and ACR with automatic analyzer DCA2000. The correlation between ACR and 24 hours urinary protein excretion was explored. And the optimal cut-off values of the spot ACR for mild and severe preeclampsia were determined with receiver operating characteristic curve. RESULTS: (1) Maternal serum biochemical parameters: uric acid levels in mild and severe preeclampsia were (359 ± 114) µmol/L and (450 ± 132) µmol/L, while cystatin levels were (1.3 ± 0.3) mg/L and (1.6 ± 0.5) mg/L respectively. The differences were statistically significant (P < 0.05). Serum urea nitrogen, creatinine and albumin in mild preeclampsia were (3.6 ± 1.6) mmol/L, (52 ± 38) µmol/L and (33 ± 3) g/L, while in severe preeclampsia were (6.2 ± 3.1) mmol/L, (78 ± 59) µmol/L and (29 ± 6) g/L respectively. There were no statistical significant differences (P > 0.05). (2) Twenty-four hours urinary protein excretion and ACR: 24 hours urinary protein levels in mild and severe preeclampsia was (700 ± 160) mg and (4800 ± 2200) mg (P < 0.05). ACR in mild and severe preeclampsia was (72.7 ± 12.4) mg/mmol and (401 ± 245) mg/mmol respectively (P < 0.05). (3) There was a strong correlation between the spot ACR and 24 hours urine protein excretion (r = 0.938; P < 0.05). (4) The optimal spot ACR cut-off point for the diagnosis of preeclampsia: the optimal spot ACR cut-off point was 22.8 mg/mmol for 300 mg/24 hours of protein excretion in mild preeclampsia, the area under curve was 0.956, with a sensitivity, specificity of 82.4%, 99.4% respectively. And the optimal spot ACR cut-off point was 155.6 mol for 2000 mg/24 hours of protein excretion in severe preeclampsia, the area under curve was 0.956, with a sensitivity, specificity of 88.6%, 91.3% respectively. CONCLUSIONS: Compared with 24 hours urinary protein excretion, the spot ACR may be a simple, convenient and accurate indicator of early diagnosis of preeclampsia. Spot ACR may be used as a replacement for 24 hours urine protein excretion in assessment of preeclampsia. The optimal spot ACR cut off points were 22.8 mg/mmol for mild preeclampsia and 155.6 mg/mmol for severe preeclampsia.

A highly efficient nano-cluster artificial peroxidase and its direct electrochemistry on a nano complex modified glassy carbon electrode.

A nano-cluster with highly efficient peroxide activity was constructed based on nafion (NF) and cytochrome c (Cyt c). UV-Vis spectrometry and transmission electron microscopy (TEM) methods were utilized for characterization of the nano-structured enzyme or artificial peroxidase (AP). The nano-cluster was composed of a Chain-Ball structure, with an average ball size of about 40 nm. The Michaelis-Menten (K(m)) and catalytic rate (k(cat)) constants of the AP were determined to be 2.5 ± 0.4 µM and 0.069 ± 0.001 s(-1), respectively, in 50 mM PBS at pH 7.0. The catalytic efficiency of the AP was evaluated to be 0.028 ± 0.005 µM(-1) s(-1), which was 39 ± 5% as efficient as the native horseradish peroxidase (HRP). The AP was also immobilized on a functional multi-wall carbon nanotube (MWNCTs)-gold colloid nanoparticles (AuNPs) nano-complex modified glassy carbon (GC) electrode. The cyclic voltammetry of AP on the nano complex modified GC electrode showed a pair of well-defined redox peaks with a formal potential (E°') of -45 ± 2 mV (vs. Ag/AgCl) at a scan rate of 0.05 V/s. The heterogeneous electron transfer rate constant (k(s)) was evaluated to be 0.65 s(-1). The surface concentration of electroactive AP on GC electrode (Γ) was 7 × 10(-10) mol cm(-2). The apparent Michaelis-Menten constant (K(m)(app)) was 0.23 nM.

[Prokaryotic expression and identification of HPV16 E7 protein].

HPV16 E7 fusion protein was expressed in E. coli BL21, and its applied value for HPV was evaluated. HPV16 E7 gene was amplified by PCR, and cloned into prokaryotic expression vector pGEX6p-1. The recombinant plasmid was transformed into E. coli BL21, and HPV16 E7 fusion was expressed through IPTG induction. The expressed product was analyzed by SDS-PAGE and Western blot, subsequently purified according to Glutathione Sepharose 4B purification procedure. An indirect ELISA with the purified fusion protein as the coating antigen was then established to detect E7 serum antibodies from mice immunized with recombinant Listeria monocytogenes delivering HPV16 E7. The results demonstrated that the soluble fusion protein was highly expressed at 25 degrees C after induction with 0.5 mM IPTG. Furthermore, the result of Western blot analysis showed that the fusion protein had good specific reaction with an anti-E7 monoclonal antibody. Indirect ELISA result confirmed that the fusion protein could detect the serum antibodies against E7 with a titer of 1:200. The expressed GST-E7 fusion protein was immunocompetent, which was useful in the research of E7 biological function and therapeutic vaccine.

[Rapid detection of chromosome number aberration in spontaneously aborted fetuses using fluorescence in situ hybridization].

OBJECTIVE: To assess the value of fluorescence in situ hybridization (FISH) in the diagnosis of common chromosome number aberration in spontaneously aborted fetuses. METHOD: A total of 100 spontaneously aborted fetuses were analyzed by G-banding and by FISH to test chromosome number aberration mainly for chromosomes 13, 18, 21, X and Y, and the results of FISH test was assessed according to those by G-banding test. RESULTS: FISH results were well consistent with those by G-banding test. FISH test identified trisomy in 32 samples and polyploidy in 7 samples. Two samples with cell culture failure were found to have trisomy 16 by FISH. Discrepancies in the results between the two tests occurred in 3 samples, but the results of FISH were verified by other methods. Kappa test between FISH technology and G-banding showed a good consistency between FISH and karyotyping (P<0.05). CONCLUSION: FISH is an effective and rapid method for detecting chromosome number aberration in spontaneously aborted fetuses, and the combination of FISH and karyotyping provides more reliable diagnostic evidence.

[Evaluations of pre-thromboembolic state in patients undergoing total abdominal or laparoscopic hysterectomy].

OBJECTIVE: To investigate the influences of total abdominal and laparoscopically hysterectomy on coagulation and fibrinolytic functions. METHODS: Blood samples were taken from 20 patients without high-risk factor of thrombosis before and after total abdominal and laparoscopically hysterectomy. The values of PT, APTT, FG, D-Dimer and AT-III were measured. RESULTS: The values of PT and AT-III significantly decreased while D-Dimer significantly increased after the operations. These changes were more obvious in patients undergoing abdominal hysterectomy. No significant changes in APTT or FG were noted after hysterectomy. CONCLUSIONS: Patients undergoing hysterectomy are at risk of developing thromboembolism, but the laparoscopic approach can significantly lower this risk as compared with abdominal hysterectomy.

[Effect of nitrogen removal simulated by RIP_ N model to a riparian zone in Guangting Reservoir catchment].

An eco-hydrological model system (RIP_ N) was constructed to simulate the nitrogen (N) removal by riparian zone in reservoir catchment scale. As a case study, the N removal in Guanting Reservoir riparian zone from March to September in 2007 was estimated. At same time, the field simulated experiment was carried out in Yanqing experimental station, which lies in the northeast part of the catchment. With the experimental data and previous studies, the RIP_ N model was calibrated. RIP_ N model was consisted with two parts, which were soil chemical process modeling and plant growth modeling. Soil chemical processes considered the soil denitrification, nitrification and ammonium volatilization. Plant growth included net primary productivity (NPP) module, plant production allocation module and nutrition uptake module. The research indicated that the correlation coefficient between simulated value and monitored value was larger than 0.5, which proved the effectiveness and reliability of RIP_ N model in catchment scale simulating. The simulated results showed that the N removal loss by riparian zone in Guanting Reservoir catchment from March to September was 5.91 x 10(3) t. The model also identified the N removal functions of different land use. At present land use condition, the bottomland, forest land and grassland contributed positively environmental benefits and removed most of N. In the temporal scale, the N removal from March to September consisted 76.5% of annual removal load. On the contrary, the wetlands just removed 5.9% of N of whole watershed. By comparison, the riparian zone was recognized as critical location for non point source pollution prevention.