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Background and Aim Although the influence of cigarette smoking on the incident risk of liver cancer has been determined, the association between smoking and liver cancer mortality remains uncertain. Methods We searched Pubmed, EmBase, and Web of Science databases to obtain eligible studies. Hazard ratio (HR) value and 95% confidential intervals (CI) were pooled by using a random-effects model, and dose–response analyses were conducted to quantify associations between smoking and mortality from liver cancer. Results A total of 27 articles involving four million participants from seven countries by retrieval (published 1986–2014) were finally included. Pooled HR values for liver cancer mortality was 1.45 (95% CI: 1.33–1.59), 1.22 (95% CI: 1.11–1.34) and 1.16 (95% CI: 1.01–1.32) for current, former, and ever smokers, respectively, when compared with nonsmokers. The risk increased by 7.1% (95% CI: 1.4–13.2) for per additional 10 cigarettes per day and by 5.2% (95% CI: 0.02–11.2) for per additional 10 pack-years. In our population recruiting 597 patients with liver cancer, smoking status was further identified as a significant determinant factor of tumor size and serum level of gamma-glutamyl transpeptidase, but not a significant prognostic factor. Conclusions Cigarette smoking, especially current smoking, significantly increased mortality risk from liver cancer.

To investigate the clinical value of pulse-induced contour cardiac output (PiCCO) monitoring combined with passive leg raising (PLR) test in predicting fluid responsiveness so as to guide fluid resuscitation in adult septic shock patients managed by rehydration test. One hundred and forty five adult septic shock patients, who were informed to receive PLR tests and rehydration tests. Patients were divided into two groups based on the observation of fluid responsiveness in the rehydration test. Parameters including heart rate (HR), central venous pressure (CVP), systolic blood pressure (SAP), mean arterial pressure (MAP), pulse pressure (PP), pulse indicates cardiac index (PCCI), central venous blood saturation in oxygen (ScvO2) and stroke fluid (SV) were monitored. By PLR test, CVP, SAP, MAP, PP, PCCI and ScvO2 were all increased significantly in the responding group; CVP, SAP, MAP, PP, PCCI and ScvO2 were all upregulated in the responding and nonresponding groups after PLR test (all P < 0.05). By rehydration test, CVP, MAP, PCCI, ScvO2 and SV were elevated in the responding group; and CVP, MAP and PCCI improved significantly both in both groups after rehydration test (all P < 0.05). PLR-ΔSV and PLR-ΔPP (PLR induced changes in stroke fluid) were both positively correlated with ΔSV (the rate of change of stroke fluid induced by fluid infusion test) (both P < 0.05). PLR combined with PiCCO may predict the fluid responsiveness in adult patients with septic shock by monitoring PLR-ΔSV associated with PLR-ΔPP, thereby contribute effectively to the guidance of fluid resuscitation.

Phosphodiesterase type 5 (PDE5) inhibitors are widely used in the treatment of male erectile dysfunction and pulmonary hypertension. Recently, several groups have evaluated the ability of PDE5 inhibitors for their anticancer activities. Previously, we had shown that sildenafil, vardenafil and tadalafil could reverse P‐glycoprotein (ATP‐binding cassette B1)‐mediated MDR. In the present study, we determined whether these PDE5 inhibitors have the potential to reverse multidrug resistance protein 7 (MRP7; ATP‐binding cassette C10)‐mediated MDR. We found that sildenafil and vardenafil dose‐dependently enhanced the sensitivity of MRP7‐transfected HEK293 cells to paclitaxel, docetaxel and vinblastine, while tadalafil had only a minimal effect. Accumulation and efflux experiments demonstrated that sildenafil and vardenafil increased the intracellular accumulation of [3H]‐paclitaxel by inhibiting the efflux of [3H]‐paclitaxel in HEK/MRP7 cells. In addition, immunoblot and immunofluorescence analyses indicated that no significant alterations of MRP7 protein expression and localization in plasma membranes were found after treatment with sildenafil, vardenafil or tadalafil. These results demonstrate that sildenafil and vardenafil reverse MRP7‐mediated a MDR through inhibition of the drug efflux function of MRP7. Our findings indicate a potentially novel use of PDE5 inhibitors as an adjuvant chemotherapeutic agent in clinical practice. (Cancer Sci, doi: 10.1111/j.1349‐7006.2012.02328.x, 2012)

Using ultrafine calcium carbonate to reinforce natural rubber latex film, the effect of its content on latex properties such as surface tension, viscosity, mechanical stability, and heat stability and the physical properties of latex film before and after aging such as tear strength, modulus, and tensile strength were investigated. The results showed that the surface tension of natural rubber latex reinforced by ultrafine calcium carbonate only changed slightly; when the content of calcium carbonate was less than 20%, the change of viscosity was not obvious, but when the content was greater than 20%, the viscosity significantly lowered. Ultrafine calcium carbonate could effectively improve the tear strength, tensile strength, and modulus of the natural rubber latex film. The modulus increased with the increment of the calcium carbonate. When the content of calcium carbonate was less than 15%, the tear strength and tensile strength increased with the increments of calcium carbonate, but when the content was greater than 15%, the above-mentioned properties decreased with the increment of calcium carbonate. By comprehensive consideration, the best reinforcing effect was obtained at a content of 15% ultrafine calcium carbonate. The particle diameters of calcium carbonate and their distribution in the calcium carbonate emulsion and in the rubber film were analyzed with SEM and a laser particle size tester, which showed that the distribution of calcium carbonate in the latex film was even and that it could effectively reinforce natural rubber latex film. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 87: 982–985, 2003

Infrared spectra of polyamide-6 (PA6) with and without epoxidized natural rubber (ENR) are presented. The influence of ENR used as a compatibilizer on the morphologies, crystallizability, mechanical properties, and thermal behavior of the polyamide-6/polyolefins (PO) blends are studied. The infrared spectra suggest that under normal processing conditions, the carboxyl end groups of PA6 could chemically react in situ with the epoxy groups of ENR, and ester groups are created. This means that the PA6-ENR grafting copolymer could be obtained during processing. All the morphological characterizations and thermal analyses show that the compatibility of PA6/PO blends is obviously improved by ENR because the copolymer increases the interaction between PA6 and PO. It is also found that the toughness of PA6/PO blends increase significantly after using ENR, while the tensile strength and the softening temperature of PA6/PO blends have almost no change. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 398–403, 2003

High-resolution pyrolysis gas chromatography-mass spectrometry (HRPyGC-MS) and Fourier transform infrared spectrometry (FTIR) were used to study the structures of the chlorinated natural rubbers (CNR) prepared by two different processes. The results indicate that the fine structures of CNR prepared from “latex” and “solution” processes are different, whereas their basic structures are similar. The molecule of CNR from the “latex” process contains a few carboxyl and carbonyl groups. The rings on CNR molecular chains should be hexatomic rings. The optimum pyrolytic temperature for CNR is 445°C, with an available range from 386 to 590°C. The characteristic pyrolytic products are cyclohexane homologues. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 87: 199–204, 2003

By mixing natural rubber latex uniformly with methyl methacrylate-grafted natural rubber latex and then carrying out prevulcanization, we obtained blends with stable viscosities. Under certain blending ratios, the blends maintained good basic properties, and the heat stability time (THS) of the blend increased with the increment of percent content of MG49 latex (C). The relationship between THS and C was THS = 0.36C + 33.0, whereas, the mechanical stability time (TMS) was slightly decreased, and the relationship between TMS and C was TMS = −1.33C + 772.0; The modulus, antiaging properties, and tear strength of the films of the blends increased with the increment of C; the tensile strengths fluctuated on a small scope; the Shore A hardness (H) and breaking set (BS) both increased with the increment of C; their relationships were H = 0.66C + 40.0 and BS = 0.46C + 8.0, respectively. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 85: 1736–1741, 2002

Novel starlike C60-bonding polymers were synthesized by using the iniferter technique. The fullerene C60 with pendent N,N-diethyldithiocarbamate groups (C60–SR) was used as polyfunctional photoiniferter. The effects of UV-irradiation time and ambient temperature on the molecular weight of polymer were investigated. The photopolymerization with C60–SR proceeded via a living-radical mechanism, and gave soluble polyfunctional polymers (photoiniferters). Multiple polymer arms were attached to the C60 core and the polymers obtained by C60–SR could also be used as excellent crosslinking agents. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 1286–1290, 2001

The thermal degradation of poly(3-hydroxybutyrate) (PHB) and poly(3-hydroxybutyrate-co-3-hydroxyvalerate) [P(HB-HV)] was studied using thermogravimetry (TG). In the thermal degradation of PHB, the temperature at the onset of weight loss (T o ) was derived by T o = 0.97B + 259, where B represents the heating rate (°C/min). The temperature at which the weight loss rate was maximum (T p ) was T p = 1.07B + 273, and the final temperature (T f ) at which degradation was completed was T/ = 1.10B + 280. The percentage of the weight loss at temperature T p (C p ) was 69 ± 1% whereas the percentage of the weight loss at temperature T f (C f ) was 96 ± 1%. In the thermal degradation of P(HB-HV) (7:3), T o = 0.98B + 262, T p = 1.00B + 278, and T f = 1.12B + 285. The values of C p and C f were 62 ± 7 and 93 ± 1%, respectively. The derivative thermogravimetric (DTG) curves of PHB confirmed only one weight loss step change because the polymer mainly consisted of the HB monomer only. The DTG curves of P(HB-HV), however, suggested multiple weight loss step changes; this was probably due to the different evaporation rates of the two monomers. The incorporation of 10 and 30 mol % of the HV component into the polyester increased the various thermal temperatures (T o , T p , and T f ) by 7-12°C (measured at B = 20°C/min).

The dynamic variations of molecular structure and properties of natural rubber (NR) during the accelerated storage have been studied. The results showed that, with the prolonging of the storage time, the average molecular weight and the gel content increased, the width index of molecular weight distribution decreased, the gel size increased gradually, but the crosslinking density of gel fluctuated only within a narrow range. Besides, the initial plasticity increased, whereas the plasticity retention index decreased. The studies with thermal analyses and infrared spectroscopy showed that the thermal degradation temperature dropped, the thermal degradation rate increased, and the thermal stability has decreased after the storage of NR. The molecular structure and properties of NR are in a state of dynamic variation during accelerate storage.

The thermal degradation and thermooxidative degradation of epoxidized natural rubber (ENR) were studied by thermogravimetry (TG). In the thermal degradation of ENR, the initial temperature of weight loss T0 = 1.20B + 348, the temperature of maximum weight loss rate Tp = 1.07B + 392, and the final temperature of weight loss Tf = 0.77B + 445. The Cp, which corresponds to the degradation rate at temperature Tp, increases along with the heating rate B and its mean value is 43%, but Cf, which corresponds to the degradation rate at temperature Tf, is not affected by the heating rate, and its average value is close to 100%. As in the thermooxidative degradation, T0 = 1.84B + 246, Tp = 0.30B + 378, and Tf = 2.27B + 584. The value of Cp increases along with the heating rate B and its mean value is 36%, but Cf is not affected by the heating rate and the average value approximately equals 100%. The thermal degradation in nitrogen could be a one-step reaction, whereas the thermooxidative degradation has a multiple-step reaction. The reactive environment has a great effect on the thermal degradation of ENR and the difference of the mechanisms of the two reaction systems is obvious. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 67:2207–2211, 1998

Four hundred forty-six serum samples from HBsAg-positive chronic hepatitis B patients were collected from five areas in China (eastern coastal city, Shanghai; southwestern inland city, Chengdu; mid-inland city, Wuhan; southern island city, Haikou; and northeastern city, Changchun). Precore stop codon variants (e-minus mutants) were screened using a rapid method of polymerase chain reaction (PCR) amplification of a precore and partial core gene fragment (nucleotides 1785–2172), followed by dot-blot hybridization with specific oligonucleotide probes (M0, and M1 + M2). The sequence of the M0 probe covered the distal precore region of wild-type virus (nucleotides 1887–1908), and the sequences of the M1 and M2 probes were from sequences mutated at nt. 1898, (TGGTAG) with or without additional change at nt. 1901. A significantly lower incidence of the precore stop codon was found in anti-HBe-positive serum samples from Haikou (17.6%), whereas in other areas the percentages of this mutation in anti-HBe positive sera ranged from 47.4% to 78.9%. In HBeAg-positive samples, the rate of e-minus mutant in coexistence with wild-type virus was low in specimens from Haikou (9.5%) and Changchun (2.9%) compared to other areas in China. In contrast, coexistence of mutant and wild-type virus was frequently detected in samples from Wuhan (50.0%). J Med Virol 51:85–89, 1997. © 1997 Wiley-Liss, Inc.