Temperature and Infill Density Effects on Thermal, Mechanical and Shape Memory Properties of Polylactic Acid/Poly(ε-caprolactone) Blends for 4D Printing.

Polylactic acid (PLA)/poly(ε-caprolactone) (PCL) blends have exhibited good shape memory properties and degradable characteristics in various 4D printing fields such as biomedicine, flexible electronics, and soft robotics, where the service temperature fluctuates easily by environment temperature and polymer characteristics. In this work, printed PLA/PCL 4D samples with different infill densities were prepared by material extrusion printing of pre-extruded filaments and characterized under different temperatures. The results show that the microstructures of printed samples are not influenced by printing process and have similar unique orientation as that of filaments. The thermal properties are stable and show obvious phase transition temperatures, while the mechanical properties decrease slightly in low temperature region and then decrease rapidly when temperature is over 60 °C. The increase in infill density can further improve the storage modulus more than 40% and have no significant influence on the thermal properties. The printed samples also exhibit good shape memory performances with fast recovery speeds less than 22 s. Furthermore, a two-step model is provided to predict the effective modulus of printed PLA/PCL samples and agrees well with experimental data. The results prove that temperature and infill density have different influences on the thermal, mechanical and shape memory properties of PLA/PCL blends.

Effects of SOCS1-overexpressing dendritic cells on Th17- and Treg-related cytokines in COPD mice.

BACKGROUND: In this study, we established a chronic obstructive pulmonary disease (COPD) model by stimulating mice with cigarette smoke, and observed the effects of dendritic cells (DCs) overexpressing SOCS1 on Th17, Treg and other related cytokines in peripheral blood, bronchoalveolar lavage fluid and lung tissues of COPD mice. METHODS: After successfully transfecting DCs with overexpressing SOCS1 (DC-SOCS1), the mice were injected with DC-SOCS1 (1 × 106), DC-SOCS1 (2 × 106) and immature DCs (1 × 106) via tail vein on days 1 and 7 of COPD fumigation modeling. After day 28 of modeling, the peripheral blood, BALF and lung tissue samples were extracted from the mice, and the changes of DCs, Th17 and Treg cells and related cytokines were detected by immunohistochemistry, immunofluorescence, HE staining, flow cytometry and ELISA. RESULTS: The results showed that DC-SOCS1 was able to reduce the secretion of pro-inflammatory factors and increase the anti-inflammatory factors in the COPD mice, and the effect of high concentration (2 × 106 DC-SOCS1) was better than low concentration (1 × 106 DC-SOCS1). Moreover, the intervention effect was significant on day 1 compared with day 7. In the mice injected with DC-SOCS1, the expression of CD83, IL-4, Foxp3, and CCR6 was increased on day 1 than those on day 7, while IL-17 and IFN-γ was decreased. CONCLUSIONS: Intervention of COPD mice with high concentrations of DCs-SOCS1 reduced pro-inflammatory factor secretion and attenuated the inflammatory response in COPD. Trial registration Not applicable.

Autophagy and pulmonary disease.

Autophagy is a process of cell self-renewal that is dependent on the degradation of the cytoplasmic proteins or organelles of lysosomes. Many diseases, such as metabolic diseases, cancer, neurodegenerative diseases, and lung diseases, have been confirmed to be associated with elevated or impaired levels of autophagy. At present, studies have found that autophagy participates in the regulation of chronic obstructive pulmonary disease (COPD), idiopathic pulmonary fibrosis, pulmonary hypertension, acute lung injury, lung cancer, and other pulmonary diseases. Using recent literature on the signal transduction mechanisms of autophagy and the effects of autophagy signalling on lung diseases, this review intends to clarify the mechanisms of lung disease to guide the treatment of related diseases. The reviews of this paper are available via the supplemental material section.

Preparation of a Thermally Light-Transmittance-Controllable Film from a Coexistent System of Polymer-Dispersed and Polymer-Stabilized Liquid Crystals.

Polymer-dispersed liquid crystal (PDLC) and polymer-stabilized liquid crystal (PSLC) systems are the two primary distinct systems in the field of liquid crystal (LC) technology, and they are differentiated by their unique microstructures. Here, we present a novel coexistent system of polymer-dispersed and polymer-stabilized liquid crystals (PD&SLCs), which forms a homeotropically aligned polymer network (HAPN) within the LC droplets after a microphase separation between the LC and polymer matrix and combines the advantages of both the PDLC and PSLC systems. Then, we prepare a novel thermally light-transmittance-controllable (TLTC) film from the PD&SLC system, where the transmittance can be reversibly changed through thermal control from a transparent to a light-scattering state. The film also combines the advantageous features of flexibility and a potential for large-scale manufacturing, and it shows significant promise in future applications from smart windows to temperature sensors.

Effect of a Polymercaptan Material on the Electro-Optical Properties of Polymer-Dispersed Liquid Crystal Films.

Polymer-dispersed liquid crystal (PDLC) films were prepared by the ultraviolet-light-induced polymerization of photopolymerizable monomers in nematic liquid crystal/chiral dopant/thiol-acrylate reaction monomer composites. The effects of the chiral dopant and crosslinking agents on the electro-optical properties of the PDLC films were systematically investigate. While added the chiral dopant S811 into the PDLC films, the initial off-state transmittance of the films was decreased. It was found that the weight ratio among acrylate monomers, thiol monomer PETMP and the polymercaptan Capcure 3-800 showed great influence on the properties of the fabricated PDLC films because of the existence of competition between thiol-acrylate reaction and acrylate monomer polymerization reaction. While adding polymercaptans curing agent Capcure 3-800 with appropriate concentration into the PDLC system, lower driven voltage and higher contrast ratio were achieved. This made the polymer network and electro-optical properties of the PDLC films easily tunable by the introduction of the thiol monomers.

Phytoremediation potentiality of garlic roots for 2,4-dichlorophenol removal from aqueous solutions.

2,4-Dichlorophenol (2,4-DCP) is considered as an important pollutant because of its high toxicity and wide distribution in wastewaters. Innocuous remediation technologies have been studied for the removal of this pollutant. This study investigated the feasibility of using garlic roots as a plant system for the removal of 2,4-DCP. The optimal conditions for its removal were established based on orthogonal experiments (OA25 matrix). Significant factors that affect removal efficiency, arranged from high to low importance, include pH, reaction time, 2,4-DCP concentration, and H2O2 concentration. In addition, garlic roots could be re-used for as much as three consecutive cycles. The decrease in pH and the increase of Cl(-) ion content in the post-removal solutions indicated that 2,4-DCP dehalogenation occurred during transformation. Changes in the deposition pattern of lignin in roots exposed to 2,4-DCP suggested that several of the products deposited were lignin-type polymers. The acute toxicity test revealed that the post-removal solutions were less toxic than the parent solutions. Therefore, garlic roots have considerable potential to effectively and safely remove 2,4-DCP from wastewater.

Photodynamic therapy for intractable bronchial lung cancer.

OBJECTIVE: To investigate the effectiveness and side effects of photofrin-photodynamic therapy (PDT) for intractable bronchial lung cancer. METHODS: Thirty patients were classified as stage II-IV intractable bronchial lung cancer with lumen obstruction after they failed previous treatment regimens such as surgery, radiotherapy and chemotherapy. PDT was performed with 630 nm laser light (Diomed) delivered through cylinder diffusing tip quartz fibers that was passed through the biopsy channel of a flexible endoscope 48 h after intravenous injection of the photosensitizer photofrin (2mg/kg body weight). 72 h after the first irradiation, the endoscopic procedure was repeated, necrotic tissues were mechanically removed and the deep original lesions and newly exposed cancer lesions were re-treated, and, if necessary, the areas were cleaned repeatedly. RESULTS: The total response rate CR+PR was 86.7%, and the mean percentage of obstruction due to tumors at different treated sites decreased from 90% to 16.7% at discharge after PDT. The KPS score was significantly improved after PDT. CONCLUSIONS: PDT of intractable bronchial lung cancer effectively reduces the amount of lumen obstruction, and improves the patient's quality of life. It may be an effective palliative treatment with minor side effects on patients with advanced bronchial lung cancer.

Retrospective study of photodynamic therapy vs photodynamic therapy combined with chemotherapy and chemotherapy alone on advanced esophageal cancer.

OBJECTIVE: To compare the short-term curative effect of photodynamic therapy (PDT), PDT combined with chemotherapy and chemotherapy alone on the advanced esophageal cancer patients. METHODS: Retrospective analysis of 90 patients of esophageal cancer underwent PDT, PDT combined with chemotherapy and chemotherapy alone from 2004 to 2007 (stages III-IV), including 27 cases received PDT alone, 33 cases received PDT combined with chemotherapy and 30 cases chemotherapy alone. The enrolled patients were treated with intravenous administration of Photofrin as the photosensitizer at a dose of 2mg/kg. 630 nm laser irradiation was performed through optical fiber that passed through the biopsy channel of a flexible endoscope after 48 h. Two days later, the necrotic tissue was removed, and the primary sites and other newly identified lesions were subjected to a second irradiation and then the residual necrotic tissue was removed according to the patients' condition. Electronic endoscopy was performed to observe the effectiveness on tumor after 1 month. In PDT combined with chemotherapy group, chemotherapy regimen was 5-FU and DDP, administered 4 cycles after PDT and chemotherapy alone group only chemotherapy regimen 5-FU and DDP for four cycles. All the 90 patients were followed up for 2 years. RESULTS: Symptomatic palliation rate of the PDT alone group, the complex treatment group and chemotherapy alone group was 85.2%, 93.9% and 60.0%, respectively, and effective rate under endoscopy was 85.2%, 90.9% and 63.3%, respectively, there is no statistically significant difference; the survival rate of 2 years was 29.6%, 54.5% and 16.7%, respectively, and medium survival time is longer (III stages 13 m, 22 m, 10 m; IV stages 7 m, 5m, 4m), there is statistically significant difference (p=0.046). CONCLUSION: PDT combined with chemotherapy for the advanced esophageal cancer is superior to PDT alone and chemotherapy alone.

[Correlation analysis between multi-slice CT perfusion imaging and microvessel density in ovarian tumors].

OBJECTIVE: To analyze the correlation between the perfusion data and microvessel density (MVD) in ovarian tumors, and investigate the hemodynamic features of the tumors in terms of anatomy and functional CT imaging. METHODS: Six patients with surgically confirmed benign ovarian tumors and 6 with malignant ovarian tumors underwent multi-slice CT perfusion imaging to acquire the perfusion parameters including perfusion, PEI, TTP, BV peak enhancement image(PEI), time to peak(TTP) and blood volume(BV). The tumors were stained and counted by Immunohistochemical staining of the microvessels in the tumor was performed to detect the MVD. RESULTS: s The time-density curves of the benign ovarian tumors increased slowly, reaching the peak at 40 s; the curves of the malignant tumors rose rapidly and continuously and reached the peak at 25 s. The differences in the perfusion data (PEI, TTP, BV) were statistically significant between the benign and malignant tumors (P<0.05). The MVD of the malignant tumors was significantly greater than that of the benign tumors (P<0.05). The mean BV of the malignant ovarian tumor was positively correlated to MVD (r=0.786, P<0.05). CONCLUSION: Multi-slice spiral CT perfusion imaging can provide accurate enhancement data of the ovarian tumors and helps in the diagnosis and differential diagnosis of the ovarian tumors by presenting the changes of the hemodynamic features in the tumors.

[Isolation, identification and degradation characterization of a polychlorinated biphenyls-degrading bacterium Pseudomonas sp. DN2].

A polychlorinated biphenyls-degrading bacterium DN2, using biphenyl as sole carbon source and energy source, was isolated from long-term PCBs-contaminated soil. Through morphological observation and sequence analysis of 16S rDNA, the strain was identified as Pseudomonas sp.. By identification of bphA1 core segment of biphenyl dioxygenase (BPDO) and enzyme activity assay of 2, 3-dihydroxybiphenyl-1,2-dioxygenase, the PCBs/biphenyl degradation-related genes in the bacterium was confirmed. Using GC-MS and resting cells PCBs degradation capacity test, the strain could remove 67% of the Aroclor 1242 in 3 days with 30%-90% of degradation rate of Aroclor 1242 congeners, which can contribute to the in situ bioremediation for the PCBs contaminated field.

[Atypical magnetic resonance imaging vs pathological findings of leiomyoma in the female reproductive system].

OBJECTIVE: To investigate magnetic resonance imaging (MRI) findings of the atypical leiomyoma in the female reproductive system in comparison with the pathological features of the neoplasms. METHODS: A retrospective analysis of the MRI findings and the pathological features was conducted in 24 cases of atypical leiomyoma involving the female reproductive system. RESULTS: Atypical leiomyomas were displayed by MRI as solid tumor mass surrounded by cystic degeneration, pseudotumors, or solid mass with homogeneous signal intensity. Intrauterine lesions were found in 19 cases, involving the subserosal layer (n=11), intramural region (n=4), broad ligament (n=3), cervix (n=2), submucous layer (n=2), vagina (n=1), and the ovary (n=1). Except for two cases with submucous lesions shown as solid mass, all the cases had lesions appearing as solid cystic mass, whose solid part showed hypo or isointense signals on T1WI and moderate hyperintense signals on T2WI, with heterogeneous enhancement after contrast agent injection. Tumor cell and interstitial cell swelling, vascular hyalinosis, hyalinosis, myxoedema, cystic degeneration, and hemorrhage were found in the lesions. CONCLUSION: Leiomyoma can occur at almost any site in the female reproductive system, and atypical leiomyoma usually are shown as solid cystic mixed mass in the pelvic cavity. Evaluation of the relationship between the solid mass and cystic portion and observation for the presence of low signal on T2WI may help in the diagnosis of atypical leiomyoma.

[Effects of EGb761 on hippocamal synaptic plasticity of vascular dementia rats].

AIM: To investigate the effects of ginkgo biloba extract 761 (EGb761) on synaptic plasticity in hippocampus of vascular dementia (VD) rats. METHODS: The escape latency (EL) of Morris water maze (MWM) task was measured at different time points (4 W, 8 W and 16 W), and the population spikes (PS) of granule cell layer in the dentate gyrus were induced by single pulse stimulation to perfo rate path fibers before and after high frequency stimulation (HFS) in vivo. RESULTS: MWM test showed that the escape latency (EL) of VD model group were highly longer than that of the sham-operated group, while the EL of EGb761-treated group was significantly shorter than that of model group, but still longer than that of the sham-operated group. The incidence rates of LTP induction in 1 m, 2 m and 4 m subgroups of model group were significantly lower than that of sham-operated group and EGb761-treated group at different time point. The relative amplitudes of PS after HFS in 1 m, 2 m and 4 m subgroups of model group were obviously reduced compared with that of the corresponding subgroups of sham-operated group and EGb761-treated group. There was no obvious significance in the peak latency of PS between different subgroups and different LTP-tested time point. CONCLUSION: VD model rats had apparent and long-lasting dysfunction of learning and memory, EGb761 could accelerate the recovery of the pathological synaptic plasticity. This suggested that EGb761 played an important and improving role on learning and memory dysfunction of VD.

[Characteristics and influencing factors of ammonia contamination from production of monosodium glutamate].

Fluxes of ammonia contamination from production of monosodium glutamate (MSG) were quantitatively observed and relationships with some important influencing factors were statistically analyzed. The study indicates that there is a big difference in the release of ammonia at each step of MSG production including sewage treatment, depending on technical processes. The flux of ammonia released in the process of fermentation was highest, up to 880 mg x (L x min)(-1), and that in the process of refining sugar was lowest, only 0.07 mg x (L x min)(-1). Fluxes of NH3 emission during the whole process of MSG production are significantly related with the concentration of ammonium-nitrogen (NH4+ -N) in discharged solution linearly, and with concentrations of nitrate-nitrogen (NO3- -N) including nitrite-nitrogen (NO2- -N) in discharged solution exponentially. Although there is no linear relationship between fluxes of NH3 emission during the whole process of MSG production and pH values in discharged solution, it is significantly related with fluxes of NH3 emission during the process of sewage treatment.

[Hydrolysis and mechanism of wastewater contained protein using immobilized protein enzyme].

Protein-enzyme was immobilized on big-hole resin, activated charcoal and silica particles by a absorption method. This study focuses on effect of enzyme immobilization, thermal stability and hydrolysis efficiency of wastewater. The result of batch test show that the ratio of immobilized enzyme on activated charcoal, big-hole resin and silica particles was 61.95%, 37.85% and 20.31% respectively. The highest of thermal ability of activated charcoal, big-hole resin and silica particles was 18.68 mg/min, 21.48 mg/min and 3.6 mg/min respectively at pH 5.5. The total amino-acids of big-hole resin and activated charcoal immobilized enzyme after hydrolysis was respectively increased to 21.26 times and 14.6 times. The kind of amino-acid was increased from 14 to 16 kinds. The continuous-flow test result indicate that concentration of substrate in influent had significant effect on the hydrolysis rate of immobilized enzyme reactor. The reactor was able to gain hydrolysis rate of 80% for protein and 36.1% (VFA/COD%) for organic materials in the wastewater with a moderate concentration of protein (500 mg/L). The ethanol and acetic of volatile hydrolysis-mixture composition were 50.3% and 33.3% respectively.

Screening of flocculant-producing microorganisms and flocculating activity.

A strain saccharomycete STSM-1 with high flocculanting activity was isolated from activated sludge with conventional methods. The high production rate and the low cost STSM-1 medium was obtained by selecting different kinds of media, carbon source, nitrogen source and inorganic salt ion. The best flocculant-producing conditions were found by changing medium initial pH, culture temperature and ventilation flow. The best flocculating effect was obtained by changing positive ion types, density and concentration of flocculant.

[A case control study on the risk factors of male infertility].

OBJECTIVE: To study the risk factors of male infertility. METHOD: Case control study including 94 cases and control group with a ratio of 1 to 1. RESULTS: The risk factors of male infertility were long time heavy smoking habit (OR = 3.45, 95% CI: 1.95 - 6.10), illegal sexual intercourse (OR = 7.29, 95% CI: 2.54 - 20.89), growing vegetable under plastic in higher temperature (OR = 6.73, 95% CI: 1.91 - 23.69), contact with benzene chemicals (OR = 20.53, 95% CI: 4.67 - 90.25) and having Ureaplasma urealyticum (Uu) infection (OR = 5.55, 95% CI: 2.28 - 13.53). CONCLUSION: Male infertility was resulted from many factors repeatedly acting on men for long time. In order to prevent male infertility, issues as environmental pollution, occupational protection need to be improved while bad working condition and risky behavior should be changed.