OBJECTIVETo detect the expression of PSF1 (partner of Sld five 1) in colon cancer specimens, and to explore the effect of RNA interference targeting PSF1 on the proliferation of colon cancer cells and its mechanism.

METHODSExpression level of PSF1 protein in colon cancer specimens was detected by Western blot in 40 patients with colon cancer from May 2004 to December 2006. The short hairpin RNA (shRNA) plasmid targeting PSF1 was transfected into LOVO, HT-29 and HCT116 cells with liposome, then the expression level of PSF1 protein was measured by Western blot, the effect of PSF1 shRNA plasmid transfection on cell proliferation by MTT assay, anchorage-independent growth by soft agar colomy-formation assay, and PSF2, PSF3 and SLD5 mRNA expression by quantitative reverse transcription polymerase chain reaction.

RESULTSThe relative expression level of PSF1 protein in colon cancer tissues was 0.485±0.113, which was significantly higher than that in adjacent normal mucosa tissues (0.056±0.014, P<0.01). Western blot showed that the expression level of PSF1 protein was significantly decreased in colon cancer cells transfected with PSF1 shRNA plasmid. After PSF1 shRNA plasmid transfection, cell proliferation was significantly suppressed, the soft agar colony-forming rates of LOVO, HT-29 and HCT116 cells were significantly lower than those in control groups (P<0.05), meanwhile the expression levels of PSF2, PSF3 and SLD5 mRNA were significantly decreased (P<0.05).

CONCLUSIONSPSF1 is significantly up-regulated in colon cancer tissues compared with adjacent normal mucosa tissues. ShRNA plasmid targeting PSF1 can inhibit the expression of PSF1 gene, suppress the proliferation of colon cancer cells, suggesting that it may be a new therapeutic target for colon cancer.

ATP-Binding Cassette Sub-Family B Member 2 ; ATP-Binding Cassette Transporters ; genetics ; metabolism ; Adult ; Aged ; Cell Line, Tumor ; Cell Proliferation ; Colonic Neoplasms ; metabolism ; pathology ; Female ; Gene Expression Regulation, Neoplastic ; Humans ; Male ; Middle Aged ; RNA Interference ; RNA, Small Interfering ; genetics ; Transfection

Purpose::With the increasing level of automation in automobiles, the advent of autonomous vehicles has reduced the tendency of drivers and passengers to focus on the task of driving. The increasing automation in automobiles reduced the drivers' and passengers' focus on driving, which allowed occupants to choose a more relaxed and comfortable sitting position. Meanwhile, the occupant's sitting position went from a frontal, upright position to a more relaxed and reclined one, which resulted in the existing restraint systems cannot to keep occupants safe and secure. This study aimed to determine the effects of different reclining states on occupants' lumbar and neck injuries.Methods::This is an original research on the field of automotive safety engineering. Occupants in different initial sitting positions (25°, 35°, 45°, and 55°) were adapted to changes in seat back angle and restraint systems and placed in the same frontal impact environment. Neck injury indexes, lumbar axial compression force and acceleration, as well as occupant dynamic response during the impact, were compared in different sitting positions. The injury response and kinematic characteristics of occupants in different reclining positions were analyzed by the control variable method.Results::As the sitting angle increased, the occupant's head acceleration decreased, and the forward-lean angle decreased. Occupants in the standard sitting position had the greatest neck injury, with an N ij of 0.95, and were susceptible to abbreviated injury scale 2+ cervical medullary injuries. As the seatback angle increased, the geometric position of the lumbar spine tended to be horizontal, and the impact load transmitted greater forces to the lumbar spine. The occupant's lumbar injury was greatest in the lying position, with a peak axial compression force on the lumbar region of 5.5 KN, which was 2.3 KN greater than in the standard sitting position. Conclusion::The study of occupant lumbar and neck injuries based on different recline states can provide a theoretical basis for optimizing lumbar evaluation indexes, which is conducive to the understanding of the lumbar injury mechanism and the comprehensive consideration of occupant safety protection.

【Objective】 To investigate the association between fetal fraction(FF) of cell-free DNA and adverse pregnancy outcomes. 【Methods】 A retrospective case-control study was conducted in 1 231 Chinese pregnant women who underwent non-invasive prenatal testing and gave birth to their children in the Third Affiliated Hospital of Sun Yatsen University during January 2017 to October 2018, including HDP group(n = 84), FGR group(n = 57) and preterm birth group(n = 59) as case groups, and the pregnant women without pregnancy-related complications were included in the control group(n = 1 031). The correlation between FF and maternal age, gestational weeks, body mass index(BMI), and comparison of FF difference in different groups were analyzed. 【Results】 In 1 031 normal pregnant women performed NIPT, the plasma FF was(12.03 ± 3.64) %, FF and maternal BMI were negatively correlated(rs = -0.079, P < 0.05). FF in HDP, FGR, preterm birth group were(11.21 ± 2.60) %, (12.48 ± 3.92) %, (11.66 ± 3.34) % , respectively. Compared with control group, FF in HDP group was statistically lower, OR = 0.926, 95%CI: 0.859-0.997, P = 0.043. FF in FGR group and preterm birth group were not statistically different compared with control group. 【Conclusions】 Low FF is a risk factor of HDP, and we may apply FF of cell-free DNA to predict the risk of HDP in further research. The correlation of FF and FGR, preterm birth have not been found yet.

The diagnosis of postradiation nasopharyngeal skull base lesions in petients with nasopharyngeal carcinoma (NPC) is still a tough problem in clinical practice. An early and accurate diagnosis is important for subsequent management. We prospectively evaluated the diagnostic value of plasma Epstein-Barr virus(EBV) DNA in detecting postradiation nasopharyngeal skull base lesions in NPC patients. From July 2006 to September 2010, 90 patients with postradiation NPC (34 women and 56 men; median age: 42 years) met the selection criteria and were recruited in this study. All postradiation nasopharyngeal skull base lesions were found in the latest magnetic resonance imaging (MRI) examinations before endoscopic surgery, and the nasopharyngeal cavity was normal under flexible nasopharyngoscopy. Plasma EBV DNA detection was performed within 2 weeks before endoscopic surgery. A total of 90 endoscopic operations were successfully performed without any postoperative complications. Recurrences confirmed by postoperative pathology were found in 30 patients. The specificity, positive and negative predictive values of plasma EBV DNA detection were better than those of MRI. In addition, combining plasma EBV DNA detection with MRI improved the specificity and positive predictive values of MRI. Plasma EBV DNA detection followed by MRI would help to diagnose recurrence whereas MRI was unable. These results indicate that plasma EBV DNA is an effective and feasible biomarker for detecting postradiation nasopharyngeal skull base lesions in NPC patients.
Adult ; Carcinoma, Squamous Cell ; blood ; radiotherapy ; virology ; DNA, Viral ; blood ; Endoscopy ; Female ; Follow-Up Studies ; Herpesvirus 4, Human ; genetics ; Humans ; Magnetic Resonance Imaging ; Male ; Middle Aged ; Nasopharyngeal Neoplasms ; blood ; radiotherapy ; virology ; Nasopharynx ; pathology ; Neoplasm Recurrence, Local ; diagnosis ; virology ; Neoplasm, Residual ; Osteoradionecrosis ; diagnosis ; surgery ; Prospective Studies ; Skull Base ; pathology

OBJECTIVETo explore the access to tobacco and exam the predictors of successful tobacco purchase attempts among Chinese minors.

METHODSA simulative trial of purchasing cigarettes was participated by 201 sixth grade students to assess the prevalence of illegal cigarette sales to minors in Guangzhou. Methods of Chi-square and unconditional logistic regression were used to identify the significant predictors,with the result of tobacco purchase as the dependent variable and the characteristics of stores, retailers and minors as the independent variables.

RESULTSA total of 165 students succeeded in purchasing cigarettes but 36 failed, and the percentage of successful purchase attempts was 82. 1% . Data from univariate analysis indicated that 9 factors were significantly associated with students' success in purchasing cigarettes. They were age and height of the purchasers, types of stores, seller's gender and age, posting cigarette advertisements,showing warning signs of 'no cigarette selling to minors' ,asking buyer's age,and asking whom you buy the cigarettes for. The results of multivariable analysis showed that only three variables entering the final logistic regression: the age of students, the type of stores, and showing warning signs of 'no cigarette selling to minors'.

CONCLUSIONChinese minors have easy access to purchasing cigarettes, especially in groceries and small markets. Selling cigarettes by sellers to minors should be monitored and managed in the future.

Adolescent ; Child ; China ; Commerce ; legislation & jurisprudence ; statistics & numerical data ; Female ; Humans ; Male ; Minors ; statistics & numerical data ; Smoking ; epidemiology ; legislation & jurisprudence ; Students ; statistics & numerical data

OBJECTIVETo investigate the expression and clinical significance of GINS complex in colorectal cancer (CRC).

METHODSThe expression level of GINS complex including PSF1, PSF2, PSF3 and SLD5 in CRC specimens (n=76) were detected by real-time fluorescent quantitative polymerase chain reaction. The association of GINS complex with clinicopathological parameters and prognosis of CRC patients were analyzed.

RESULTSThe relative expression level of PSF1, PSF2, PSF3, and SLD5 mRNA in CRC tissues was 0.001 853±0.000 651, 0.007 757±0.004 260, 0.000 967±0.000 481 and 0.003 248±0.001 721, which was significantly higher than that in normal colorectal mucosa tissues (0.000 352±0.000 169, 0.002 951±0.001 216, 0.000 472±0.000 271, and 0.001 675±0.001 156) (all P<0.01). PSF1 mRNA expression was associated with tumor size (P<0.01), and PSF2 mRNA expression with age (P<0.05) and lymph node metastasis (P<0.05). No correlations between PSF3 mRNA expression and clinicopathological parameters were observed. SLD5 mRNA expression was associated with lymph node metastasis (P<0.01). Patients with high expression of PSF1, PSF2 and SLD5 had worse 5-year overall survival rate (57.1%, 54.3%, and 54.3%) than those with low expression (77.1%, 80.0%, and 80.0%) (all P<0.05). Multivariable Cox regression analysis indicated that PSF1 mRNA expression (P<0.05) was an independent factor associated with prognosis of colorectal cancer.

CONCLUSIONSOverexpression of GINS complex in CRC is associated with clinicopathological characteristics and prognosis of colorectal cancer. PSF1 expression is prognostic for CRC patients.

Adult ; Aged ; Aged, 80 and over ; Chromosomal Proteins, Non-Histone ; metabolism ; Colorectal Neoplasms ; diagnosis ; metabolism ; pathology ; DNA-Binding Proteins ; metabolism ; Female ; Humans ; Male ; Middle Aged ; Prognosis

OBJECTIVETo study the effects of gypenoside (Gyp) on the activity of microsomal Na(+), K(+)-ATPase in rat's heart and brain in vitro.

METHODSThe microsomal Na(+), K(+)-ATPase was prepared from rat's heart and brain by differential centrifugation. The activity of microsomal Na(+), K(+)-ATPase was assayed by colorimetric technique. Enzyme kinetic analysis method was used to analyze the effect of Gyp on the microsomal Na(+), K(+)-ATPase of rats.

RESULTSGyp reversibly inhibited the brain and heart's microsomal Na(+), K(+)-ATPase in a concentration-dependent manner, and showed a more potent effect on enzyme in the brain. The IC(50) of Gyp for the heart and brain were 58.79+/-8.05 mg/L and 52.07+/-6.25 mg/L, respectively. The inhibition was enhanced by lowering the Na(+), or K(+) concentrations or increasing the ATP concentration. Enzyme kinetic studies indicated that the inhibitory effect of Gyp on the enzyme is like that of competitive antagonist of Na(+), the counter-competitive inhibitor for the substrate ATP, and the mixed-type inhibitor for K(+).

CONCLUSIONGyp displays its cardiotonic and central inhibitory effects by way of inhibiting heart and brain's microsomal Na(+), K(+)-ATPase activities in rats.

Adenosine Triphosphate ; pharmacology ; Animals ; Brain ; enzymology ; Enzyme Inhibitors ; pharmacology ; Gynostemma ; Kinetics ; Male ; Myocardium ; enzymology ; Plant Extracts ; pharmacology ; Rats ; Rats, Wistar ; Sodium-Potassium-Exchanging ATPase ; antagonists & inhibitors

OBJECTIVETo investigate the effect of a selective inducible nitric oxide synthase(iNOS) inhibitor, aminoguanidine (AG), on the proliferation and apoptosis of human colorectal cancer (CRC) Lovo cell line, and explore its possible mechanism.

METHODSMTT assay was used to detect the inhibition of Lovo cell growth by aminoguanidine. Apoptosis and cell cycle of Lovo cells were examined by flow cytometry (FCM). Morphologic change of Lovo cell treated by AG was observed with AO/EB staining.

RESULTSThere were significant differences in 0.5 mmol/L and 1.0 mmol/L AG groups as compared to the control group (P<0.05). The absorbance (A) values of Lovo cells in each time point were significantly different (P<0.05). Growth of Lovo cells was inhibited by aminoguanidine in a dose- and time-dependent manner. FCM analysis showed that the cell ratio of G(0)/G(1) phase increased with the increasing of the concentration of aminoguanidine, but the cell ratio of S-and G(2)/M phase decreased correspondingly (P<0.05). S phase fraction and proliferation index (PI) decreased remarkably, and the apoptotic rate of Lovo cells increased. After AG treatment, AO/EB staining revealed some apoptotic morphological features such as cell shrinkage, nuclear condensation, DNA fragmentation, and formation of apoptosis bodies.

CONCLUSIONSAminoguanidine inhibits the proliferation and facilitates the apoptosis of human CRC Lovo cells. One of the mechanisms may be explained as blocking the progress of cell cycle of CRC Lovo cells by aminoguanidine.

Apoptosis ; drug effects ; Cell Cycle ; drug effects ; Cell Line, Tumor ; Cell Proliferation ; drug effects ; Colorectal Neoplasms ; metabolism ; Drug Resistance, Neoplasm ; drug effects ; Enzyme Inhibitors ; pharmacology ; Guanidines ; pharmacology ; Humans ; Nitric Oxide Synthase Type II ; antagonists & inhibitors

OBJECTIVETo evaluate clinical effects of two types of nickel-titanium rotary instruments in preparation of molars' root canals.

METHODS100 molars with pupal and periapical involvement were instrumented by Protaper and Hero642 files with crown-down technique. All teeth were obturated with lateral condensation method. Straightening of canal curvature was determined. The efficiency of preparation and obturation was analyzed with radiograph before, during and after operation.

RESULTSThe operating time of each NiTi group was short. The two NiTi rotary instruments could achieve continuously tapered root canal shape. The curvature of the canal reduced by -4.02 degrees +/- 2.80 degrees with Protaper and 1.72 degrees with Hero642 (P < 0.001). Five pieces of Protaper with broken, whereas no Hero642 was broken (P < 0.05).

CONCLUSIONSProtaper, Hero642 files showed good shaping ability and improved predictability in root canal obturation. Protaper can lessen canal curvature more significantly. Hero642 files are easy to operate and not easy to separate.

Adult ; Aged ; Dental Alloys ; Humans ; Middle Aged ; Molar ; Nickel ; Periodontitis ; therapy ; Pulpitis ; therapy ; Root Canal Preparation ; instrumentation ; Root Canal Therapy ; Titanium ; Young Adult

OBJECTIVETo investigate the appropriate distal resection margin in rectal cancer patients.

METHODSThirty specimens of rectal carcinoma with total mesorectal excision(TME) were studied by flow cytometry and pathological examination. The differences of DNA ploidy status, DNA index (DI), proliferative index (PI), S-phase fraction (SPF) among rectal cancer, 3 cm and 5 cm below the tumor, normal rectum, distal mesorectum 3 cm and 5 cm below the tumor, and normal colon mesentery were analysed by flow cytometry, and were compared with the data of pathological examination.

RESULTSPathological examination showed that there was no tumor invasion 3 cm and 5 cm below the tumor,but the metastasis rates of distal mesorectum 3 cm and 5 cm below the tumor were 26.7% and 6.7% respectively. The DI, PI and SPF of rectal cancer by flow cytometric examination were significantly higher than those of distal rectum 3 cm and 5 cm below the tumor, and normal rectum (P<0.05). The DI, PI and SPF of distal rectum 3 cm below the tumor were also significantly higher than those of distal rectum 5 cm below the tumor, and normal rectum (P<0.05), but there were no significant differences between DI, PI and SPF of distal rectum 5 cm below the tumor and those of normal rectum (P>0.05). The rate of DNA aneuploid of tumor was significantly higher than those of normal rectum and distal rectum 5 cm below the tumor,but there was no significant difference between the rate of DNA aneuploid of tumor and that of distal rectum 3 cm below the tumor. The DI and DNA aneuploid of rectal cancer and distal mesorectum 3 cm and 5 cm below the tumor were significantly higher than those of normal mesorectum,but there were no significant differences between DI and DNA aneuploid of rectal cancer and those of distal mesorectum 3 cm and 5 cm below the tumor. The PI and SPF of rectal cancer were significantly higher than those of normal mesorectum and distal mesorectum 3 cm and 5 cm below the tumor.

CONCLUSIONSRectal cancer is able to invade distal rectum 3 cm below the tumor and distal mesorectum 5 cm below the tumor, and radical resection of rectal cancer should beyond that range.

Adult ; Aged ; Female ; Flow Cytometry ; Humans ; Male ; Middle Aged ; Neoplasm Staging ; Rectal Neoplasms ; pathology ; surgery ; Rectum ; pathology ; surgery ; Treatment Outcome