Targeting PTGES/PGE2 axis enhances sensitivity of colorectal cancer cells to 5-fluorouracil.

Insensitivity and resistance to 5-fluorouracil (5FU) remain as major hurdles for effective and durable 5FU-based chemotherapy in colorectal cancer (CRC) patients. In this study, we identified prostaglandin E synthase (PTGES)/prostaglandin E2 (PGE2) axis as an important regulator for 5FU sensitivity in CRC cells. We found that PTGES expression and PGE2 production are elevated in CRC cells in comparison to normal colorectal epithelial cells. Depletion of PTGES significantly enhanced the inhibitory effect of 5FU on CRC cell viability that was fully reverted by exogenous supplement of PGE2. Inhibition of PTGES enzymatic function, by either inducing loss-of-function mutant or treatment with selective inhibitors, phenocopied the PTGES depletion in terms of 5FU sensitization. Mechanistically, PTGES/PGE2 axis modulates glycolysis in CRC cells, thereby regulating the 5FU sensitivity. Importantly, high PTGES expression is correlated with poor prognosis in 5FU-treated CRC patients. Thus, our study defines PTGES/PGE2 axis as a novel therapeutic target for enhancing the efficacy of 5FU-based chemotherapy in CRC.

Simple high-performance liquid chromatography-ultraviolet method for simultaneous separation and detection of 14 bisphenol pollutants in building materials.

A high-performance liquid chromatography-ultraviolet method was developed for rapidly and simultaneously analyzing novel and typical bisphenols in building materials, including bisphenol S, diphenolic acid, bisphenol F, bisphenol E, bisphenol A, bisphenol B, bisphenol AF, bisphenol AP, bisphenol C, bisphenol FL, bisphenol Z, bisphenol BP, bisphenol M, and bisphenol P. By using a Kromasil 100-5 C18 column, these bisphenols were completely separated in 40 min via gradually increasing the concentration of methanol in the mobile phase from 45 to 80% during the elution process. In particular, this method achieved the synchronous analysis of bisphenol S, diphenolic acid, bisphenol FL, bisphenol BP, and bisphenol M through HPLC, which were difficult to separate and had to be identified and detected through mass spectrometry. The limits of detection of the method ranged from 0.002 to 0.040 mg/L for these 14 bisphenols, with a precision of less than 4.9% (n = 7, c = 0.05 mg/L). The analytical results for five types of building materials (phenolic, epoxy, polycarbonate, polyester, and polysulfone resins) indicated that the proposed method is appropriated for the rapid measurement of bisphenols in real samples.

[Correlation between cystatin C and properties and features of coronary plague].

OBJECTIVE: To explore the correlation between cystatin C (Cys C) and properties and features of coronary plague using 256-slice coronary computed tomography angiography (CTA). METHODS: From January 2013 to October 2013, a total of 184 patients with suspected coronary artery disease undergoing CTA for coronary artery lesions were enrolled. Based on the results of cystatin C levels, they were divided into normal Cys C concentration group ( ≤ 0.95 mg/L) and high Cys C concentration group (>0.95 mg/L). Based on the results of CTA, they were divided into single-vessel, 2-vessel and 3-vessel groups according to the number of diseased coronary arteries. And they were divided into mild stenosis (<50%), moderate stenosis ( ≥ 50%, <75%) and severe stenosis ( ≥ 75%) groups according to the severity of coronary artery disease. The Hounsfield units were used to determine the soft, fibrous and calcified plaques for assessing the relationship between cystatin C levels and narrow severity score, pathological changes limits, plague properties. RESULTS: There were 95 with normal concentrations of Cys C and 89 with high concentrations of Cys C. A total of 1 112 plaques were detected and those with high concentrations of Cys C showed a higher proportion of non-calcified plaque (13.5% vs 8.8%, P < 0.01) compared with normal group. The proportion of those with 1-vessel disease was lower (22.5% vs 37.9%, P < 0.05) but 3-vessel disease higher (48.3% vs 33.7%, P < 0.05) than in normal group. Multiple Logistic regression analysis revealed that high Cys C was a significant risk factor for multi-vessel disease (OR = 17.483, 95%CI:2.218-143.627; P < 0.01). CONCLUSION: For patients with coronary artery lesions, a high level of Cys C may be associated with severity of coronary atherosclerosis and plaque instability.

[Prevalence, severity, characteristics and coronary calcified score of coronary artery plaques are different in women than men with suspected coronary artery disease].

OBJECTIVE: To validate the prevalence, severity, characteristics and coronary calcified score(CACS) of coronary artery plaques in women are different from men. METHODS: A total of 3 752 patients with suspected coronary artery disease in the First Affiliated Hospital of China Medical University were enrolled between September 2011 and December 2013. Patients with suspect CAD underwent 256-detecter coronary computed tomography (CCTA) and CACS measurement were enrolled. The differences of sex-associated coronary artery plaques were assessed. The univariable and multivariable Logistic regression were employ to assess the association female and male with coronary artery plaques. RESULTS: A total of 3 752 patients including 1 832 females and 1 920 males, the average age of the patients was (56 ± 11) years. Women were older and less smoker than men. The prevalences of any plaque, 2-,3-/LM disease and significant/severe stenosis significantly decreased in female than male (all P<0.01). The proportion of non-calcified plaques significantly higher and mixed plaque significantly lower in female than male (all P<0.01). the proportion of women were significantly lower than men in CACS>0 (all P<0.01). The similar tendency also happened in four age-matched female and male subgroups. After adjustment, female was the significant protective factor for significant and severe stenosis, 2- and 3-/LM vessel disease, calcified and mixed plaques, and CACS>100 (all P<0.01); female was the significant protective factor for non-calcified plaques in the univariate analysis (P<0.01). When the age ≥ 65, female became the significant risk factor for coronary artery plaques (all P<0.01). CONCLUSIONS: Women have less prevalence and extensive coronary artery plaques and lower CACS, the plaque characteristics in women is more frequently composed by non-calcified plaques than men, even after matched by age. With age, female change from a protective factor to a risk factor for coronary artery plaques.

Construction of shRNA-Bmi-1 plasmid and its effect on proliferation of ECA109 cells.

OBJECTIVE: To explore the role of Bmi-1 gene in the proliferation of squamous carcinoma cells and whether the silencing Bmi-1 can inhibit the growth of squamous cell carcinomas cells. METHODS: The expressions of Bmi-1 in primary cultured Fibroblasts, karatinocyte cell line Hacat,squamous carcinoma cell line A431, and ECA109 were detected by reverse transcription polymerase chain reaction (RT-PCR) and Western blot analysis. Recombinant plasmid inserted with Bmi-1 gene short hairpin RNA (shRNA) expression vector PGPU6/GFP/Neo-shBmi-1 was constructed and transfected into ECA109 cells with control set. After transfection for 48 and 72 hours,the mRNA and protein levels of Bmi-1 were examined with RT-PCR and Western blot analysis, respectively. The proliferation of the ECA109 cells was evaluated by MTT method and flow cytometry. RESULTS: Bmi-1 was highly expressed in A431 and ECA109 cells than in Fibroblast cells and Hacat cells. The mRNA and protein expressions of Bmi-1 were significantly silenced in ECA109 cells after recombinant expression vector PGPU6/GFP/Neo-shBmi-1 transfection (P<0.05). Compared with the control groups,the proliferation of ECA109 transfected with PGPU6/GFP/Neo-shBmi-1 was significantly inhibited (P<0.05), and cells in G1 phase increased while in S phase decreased (P<0.05). CONCLUSIONS: Bmi-1 is involved in the proliferation of squamous carcinoma cells. After the silencing of Bmi-1 expression,the proliferation ECA109 cells is suppressed due to the altered cell cycle.

Influence of Cigarette Smoking on Burden and Characteristics of Coronary Artery Plaques in Chinese Men.

BACKGROUND: It is generally well-known that smoking has a substantial impact on general health, and cardiovascular health in particular. The purpose of this study was to analyze the effects of different smoking status on the burden and characteristics of coronary artery plaques in Chinese men. METHODS: Our study enrolled 1920 individuals with suspected coronary artery disease undergoing 256-detector-row computed tomography scan after clinical assessment. These study participants were stratified into three groups: never smoker, current smoker, and former smoker, according to their smoking status. Thereafter, the associations of different smoking status with the coronary artery plaques were assessed using both univariable and multivariable logistic regression. RESULTS: The prevalences of any plaque, significant stenosis and coronary artery calcium score (CACS) ≥ 10 were highest in the current smokers (all p < 0.05). The proportion of calcified plaques was the lowest and the prevalence of non-calcified plaques was the highest in current smokers (p = 0.004). The higher pack-years group had significantly elevated percentages of any plaque, significant stenosis, ≥ 2/LM vessel disease and CACS ≥ 10 than the lower pack-years group (all p < 0.001). The percent of calcified plaques was lower and the percent of non-calcified plaques was higher in the higher (> 20) pack-years group than in the lower pack-years group (≤ 20) (p = 0.024). Current smoking with higher pack-years was the independent risk factor for any plaque, significant stenosis, CACS ≥ 10, non-calcified and mixed plaques (all p < 0.05) after multivariate adjustments. CONCLUSIONS: The current smokers had the most serious burden of coronary artery plaques and the highest percentage of non-calcified plaques. Current smoking with higher pack-years was a significant risk factor for coronary artery plaque burden and non-calcified and mixed plaques. KEY WORDS: Chinese men; Cigarette smoking; Coronary artery calcium score; Coronary artery plaques; Non-calcified plaques.

A cross-sectional analysis of the relationship between uric acid and coronary atherosclerosis in patients with suspected coronary artery disease in China.

BACKGROUND: Although many studies have examined the relationship between uric acid (UA) and coronary artery disease (CAD), whether UA is an independent risk factor contributing to progression of CAD is still controversial. Whether UA plays a different role in different sexes is also unclear. METHODS: A total of 1116 individuals with suspected CAD were stratified into four groups according to their serum UA quartiles in total (men and women combined), in men, and in women. The association of UA with coronary atherosclerosis was assessed by univariable and multivariable logistic regression. RESULTS: In total and in women, the prevalence of any plaques and significant/severe stenosis was significantly increased with an increase in quartiles of UA (all P < 0.05). The proportion of triple-vessel disease and left main artery lesion was highest in the fourth quartile (both p < 0.05). Increasing quartiles of UA were significantly associated with a coronary artery calcium score (CACS) >10 (all P < 0.01). As UA levels increased in women, the incidence of double-vessel lesions (p = 0.017) and the proportion of mixed plaques (p = 0.022) were significantly increased. The proportion of a CACS of 0 in total, in men and women was highest in the first quartile (all P < 0.01). UA was the strongest predictor of significant stenosis, multivessel disease, and mixed plaques in women (all p < 0.05). UA was the only risk factor for mixed plaques in total (P = 0.046). CONCLUSION: The level of UA was significantly associated with coronary atherosclerosis in women, but not men.

G2(+)M study on N-alkylamino cation affinities of neutral main-group element hydrides: trends across the periodic table.

We have made an extensive theoretical exploration of gas-phase N-alkylamino cation affinities (NAAMCA), including amino cation affinities (AMCA) and N-dimethylamino cation affinities (NDMAMCA), of neutral main-group element hydrides of groups 15-17 and periods 2-4 in the periodic table by using the G2(+)M method. Some similarities and differences are found between NAAMCA and the corresponding alkyl cation affinities (ACA) of H(n)X. Our calculations show that the AMCA and NDMAMCA are systematically lower than the corresponding proton affinities (PA) for H(n)X. In general, there is no linear correlation between NAAMCA and PA of H(n)X. Instead, the correlations exist only within the central elements X in period 2, or periods 3-4, which is significantly different from the reasonable correlations between ACA and PA for all H(n)X. NAAMCA (H(n)X) are weaker than NAAMCA (H(n-1)X(-)) by more than 700 kJ/mol and generally stronger than ACA (H(n)X), with three exceptions: H2ONR2(+)(R = H, Me) and HFNH2(+). These new findings can be rationalized by the negative hyperconjugation and Pauli repulsion.

Hydrogen bond formation between the naturally modified nucleobase and phosphate backbone.

Natural RNAs, especially tRNAs, are extensively modified to tailor structure and function diversities. Uracil is the most modified nucleobase among all natural nucleobases. Interestingly, >76% of uracil modifications are located on its 5-position. We have investigated the natural 5-methoxy (5-O-CH(3)) modification of uracil in the context of A-form oligonucleotide duplex. Our X-ray crystal structure indicates first a H-bond formation between the uracil 5-O-CH(3) and its 5'-phosphate. This novel H-bond is not observed when the oxygen of 5-O-CH(3) is replaced with a larger atom (selenium or sulfur). The 5-O-CH(3) modification does not cause significant structure and stability alterations. Moreover, our computational study is consistent with the experimental observation. The investigation on the uracil 5-position demonstrates the importance of this RNA modification at the atomic level. Our finding suggests a general interaction between the nucleobase and backbone and reveals a plausible function of the tRNA 5-O-CH(3) modification, which might potentially rigidify the local conformation and facilitates translation.

Quality of life of patients with neurodermatitis.

BACKGROUND: Neurodermatitis is a common chronic skin disease. Although not life-threatening, it can produce an important psychosocial burden, sleep disturbance and sexual dysfunction. Patients with neurodermatitis tend to have poor social skills or interpersonal resources and a lack of flexibility. However quality of life (QoL) of patients with neurodermatitis has seldom investigated. The objective of this study is to assess the impact of neurodermatitis on patients' QoL using the Dermatology Life Quality Index questionnaire, and assess its feasibility and internal consistency. METHODS: One hundred and fifty consecutive outpatients seeking treatment for neurodermatitis and 250 patients with psoriasis in the Department of Dermatology, the Second Hospital of Xi'an Jiaotong University, were assessed for eligibility for this prospective study from July 1, 2011 to September 30, 2011. Demographic data and disease-related characteristics were collected. RESULTS: The overall mean DLQI score for neurodermatits (9.34) was lower than that for psoriasis (13.32) (P < 0.001). Patients with neurodermatitis scored significantly lower for all items except Q1 (symptoms) and Q9 (sexual difficulties). No strong relationship between disease-related characteristics and quality of life could be found. The inter-item correlation averaged 0.415 and Cronbach's alpha was 0.889, indicating high internal consistency. CONCLUSION: This is the first study to attempt to measure the impact of neurodermatitis for both male and female patients on QoL. Neurodermatitis moderately affected the QoL of the patients.

Generalized anomeric effect on N-alkyl-amino cation affinities: a G2(+)M investigation.

The gas-phase N-alkyl-amino-cation affinities (NAACA) of archetypal anionic main-group element hydrides across the Periodic Table have been investigated by means of a modified G2(+) scheme. The reactions studied include R(2)NB → R(2)N(+) + B(-) (R = H, Me; B = XH(n), n = 0-3; X = F, Cl, Br, O, S, Se, N, P, As, C, Si, Ge). Our calculations indicate that the reasonable linear correlations between NAACA and proton affinities (PA) only exist within the Period 2 anions, including H(3)C(-), H(2)N(-), HO(-), and F(-), or the anions within Periods 3-4 in the Periodic Table, which is significantly different from the alkyl cation affinities, where there is a reasonable correlation between the computed alkyl cation affinity and PA values of the set of anionic main-group element hydrides. The interesting differences can be ascribed to the generalized anomeric effect induced by n(N) → σ*(X-H) negative hyperconjugation found in R(2)NXH(n), with central atom X belonging to Groups 14-16 (X = O, S, Se, N, P, As, C, Si, Ge).

Comprehensive theoretical studies on the gas phase SN2 reactions of anionic nucleophiles toward chloroamine and N-chlorodimethylamine with inversion and retention mechanisms.

The anionic S(N)2 reactions at neutral nitrogen, Nu(-) + NR(2)Cl → NR(2)Nu + Cl(-) (R = H, Me; Nu = F, Cl, Br, OH, SH, SeH, NH(2), PH(2), AsH(2)) have been systematically studied computationally at the modified G2(+) level. Two reaction mechanisms, inversion and retention of configuration, have been investigated. The main purposes of this work are to explore the reactivity trend of anions toward NR(2)Cl (R = H, Me), the steric effect on the potential energy surfaces, and the leaving ability of the anion in S(N)2@N reactions. Our calculations indicate that the complexation energies are determined by the gas basicity (GB) of the nucleophile and the electronegativity (EN) of the attacking atom, and the overall reaction barrier in the inversion pathway is basically controlled by the GB value of the nucleophile. The retention pathway in the reactions of NR(2)Cl with Nu(-) (Nu = F, Cl, Br, OH, SH, SeH) is energetically unfavorable due to the barriers being larger than those in the inversion pathway by more than 120 kJ mol(-1). Activation strain model analyses show that a higher deformation energy and a weaker interaction between deformed reactants lead to higher overall barriers in the reactions of NMe(2)Cl than those in the reactions of NH(2)Cl. Our studies on the reverse process of the title reactions suggest that the leaving ability of the anion in the gas phase anionic S(N)2@N reactions is mainly determined by the strength of the N-LG bond, which is related to the negative hyperconjugation inherent in NR(2)Nu (R = H, Me; Nu = HO, HS, HSe, NH(2), PH(2), AsH(2)).

[Expression of integrin beta1 in squamous cell carcinoma].

OBJECTIVE: To study the expression of integrin beta1 in squamous cell carcinoma (SCC) and explore the relationship between stem cell marker and SCC. METHODS: The expressions of integrin beta1 in SCC tissues and SCC cell strain A431 were detected with immunohistochemical methods and cell staining method. The differentiation of SCC cells were induced with all-trans-retinoic acid (ATRA). The changes of integrin beta1 levels before and after induction were detected with RT-PCR. RESULTS: In highly differentiated SCC tissues, integrin beta1 was constantly expressed in the basal-like cells in the edge of tumor; some cells inside arranged as island also showed positive integrin beta1 expression. In poorly differentiated SCC tissues, island-like integrin beta1-positive cells remarkably increased and distributed in a diffuse way. In SCC A431 cells, integrin beta1 was expressed unevenly in tumor cells. After treatment by ATRA, level of integrin beta1 mRNA in A431 cells significantly decreased compared with untreated control (P < 0.05), and the ratios between the intensity values of integrin beta1 to beta-actin were 0.071 +/- 0.025 and 0.029 +/- 0.018 at 24 h and 48 h, respectively, whereas in controls were 0.148 +/- 0.027 and 0.136 +/- 0.011 (P < 0.05). CONCLUSIONS: Integrin beta1 is heterogeneously expressed in both SCC tissues and SCC A431 cells. The expression of Integrin beta1 decreases when the differentiation level of tumor cells increase, indicating that integrin beta1 is closely related with the initiation of SCC and potential cancer stem cells in SCC.

Induction of apoptosis by Hax-1 siRNA in melanoma cells.

HS1-associated protein X-1 (Hax-1) is a novel intracellular protein and recent studies suggested that it is an anti-apoptotic factor in different tumors. Hax-1 expression was upregulated in various metastatic tumors and cancer cell lines, including melanoma. To understand the role of Hax-1 in melanoma development and progression, we constructed Hax-1 short interfering RNA (siRNA) expression vectors to downregulate Hax-1 expression in a human melanoma A375 cell line. One of the two Hax-1 RNA interference (RNAi) constructs significantly reduced melanoma cell viability, which was due to induction of apoptosis in A375 cells. Molecularly, the induced apoptosis through downregulation of Hax-1 expression was mediated by activation of caspase-3 and poly-ADP-ribose polymerase (PARP) enzymatic activity in A375 cells. The data indicate that Hax-1 plays a role in suppression of apoptosis and promotion of melanoma cell growth, suggesting that this Hax-1 siRNA has a therapeutic indication in control of melanoma.

Immunohistochemical and ultrastructural features of Langerhans cells in condyloma acuminatum.

BACKGROUND: There are few studies on the abnormal morphology of Langerhans cells (LCs) in condyloma acuminatum (CA) lesions and the essence of the abnormal morphology of LCs in CA lesions is still not well elucidated. The aim of this study was to further investigate the morphological features of LCs in CA lesions. METHODS: CD1a(+) LCs in 13 CA lesions and in 13 normal controls were labeled using immunohistochemistry and examined by light microscopy. Ultrastructural investigation on LCs in six CA lesions and in six normal controls was performed by electron microscopy. RESULTS: Compared with those in normal controls, most CD1a(+) LCs in CA lesions exhibited dysplastic dendrities and abnormal distribution. The number of CD1a(+) LCs in CA lesions (26.31 +/- 18.84) was statistically lower (p < 0.001) than that in normal controls (72.00 +/- 27.40). Electron microscopy showed that the number of Birbeck granules within lesional LCs (4.00 +/- 2.94) was significantly decreased (p < 0.001) than that within normal LCs (10.80 +/- 4.78). The ultrastructures of most lesional LCs displayed degenerative changes. CONCLUSIONS: The morphology of most LCs in CA lesions shows degenerative changes, which suggest that these LCs have been functionally impaired.

Pulse compression radar reflectometry to measure electron density in plasma with parasitic reflections.

Pulse compression radar reflectometry is used to obtain electron density profile in plasma with parasitic reflections in this article. The pulse compression radar relies on the relation between the temporal width of a pulse and the frequency bandwidth of this pulse: Deltat proportional, variant1Deltaf. So a set of sweep-frequency microwaves within a bandwidth Deltaf can be introduced sequentially into the plasma to obtain the same information as the one obtained by a real pulse. By applying a Fourier transform to the data of reflectivity array in the frequency domain, the temporal response in the time domain is obtained. The limitation of the parasitic reflections on measurement can be eliminated from the temporal response by the method of time gate. This is a prominent advantage when this method is compared to the traditional reflectometry. For this method, an appropriate compromise between the spatial resolution and the electron density resolution is important. Experimental results show that the profile obtained from pulse compression radar reflectometry is similar to that from a double Langmuir probe.