Plastics are one of the most important polymers with huge global demand. However, the downsides of this polymer are that it is difficult to degrade, which causes huge pollution. The environmental-friendly bio-degradable plastics therefore could be an alternative and eventually fulfill the ever-growing demand from every aspect of the society. One of the building blocks of bio-degradable plastics is dicarboxylic acids, which have excellent biodegradability and numerous industrial applications. More importantly, dicarboxylic acid can be biologically synthesized. Herein, this review discusses the recent advance on the biosynthesis routes and metabolic engineering strategies of some of the typical dicarboxylic acids, in hope that it will help to provide inspiration to further efforts on the biosynthesis of dicarboxylic acids.
Biodegradable Plastics ; Dicarboxylic Acids ; Polymers/metabolism* ; Biodegradation, Environmental ; Metabolic Engineering

Objective:To analyze the efficacy of chest wall boost radiotherapy in stage T 4 breast cancer patients after modified radical mastectomy. Methods:A retrospective analysis was performed on the data of 148 stage T 4 breast cancer patients who were admitted from 2000 to 2016 and received radiotherapy after modified radical mastectomy. There were 57 cases in the chest wall boost radiotherapy group and 91 cases in the conventional dose group. Radiotherapy was performed by conventional+ chest wall electron beam, three-dimensional conformal+ chest wall electron beam, intensity modulated radiotherapy+ chest wall electron beam irradiation. EQD 2 at the boost group was >50Gy. All patients received neoadjuvant chemotherapy. Kaplan-Meier method was used to analyze survival; Logrank was used to test differences; and Cox model was used to do multivariate prognostic analysis. Results:The median follow-up time was 67.2 months. The 5-year rates of chest wall recurrence (CWR), locoregional recurrence (LRR), disease-free survival (DFS), and overall survival (OS) were 9.9%, 16.2%, 58.0%, and 71.4%, respectively. The 5-year rates of CWR, LRR, DFS, and OS with and without chest wall boost radiotherapy were 14% vs. 7%, 18% vs. 15%, 57% vs. 58%, 82% vs. 65%( P>0.05), respectively. Multivariate analysis showed that chest wall boost radiotherapy had no significant effect on prognosis ( P>0.05). Among 45 patients in the recurrent high-risk group, boost radiotherapy seemed to have higher OS rate ( P=0.058), DFS rate ( P=0.084), and lower LRR rate ( P=0.059). Conclusions:Stage T 4 breast cancer patients had strong heterogeneity. Chest wall boost radiotherapy did not apparently benefit all patients. For patients with 2-3 high risk factors including positive vascular tumor embolus, pN 2-N 3, and hormone receptor negative, chest wall boost radiotherapy showed a trend of improving efficacy.

Purpose: Accumulating evidence has suggested that toll-like receptor 4 (TLR4) is critically involved in the pathogenesis of asthma. The aim of this study was to investigate the role of TLR4 in toluene diisocyanate (TDI)-induced allergic airway inflammation. Methods: TLR4−/− and wild-type (WT) C57BL/10J mice were sensitized and challenged with TDI to generate a TDI-induced asthma model. B-cell lymphoma 2 (Bcl-2) inhibitors, ABT-199 (4 mg/kg) and ABT-737 (4 mg/kg), were intranasally given to TDI-exposed TLR4−/− mice after each challenge. Results: TDI exposure led to increased airway hyperresponsiveness (AHR), granulocyte flux, bronchial epithelial shedding and extensive submucosal collagen deposition, which were unexpectedly aggravated by TLR4 deficiency. Following TDI challenge, TLR4−/− mice exhibited down-regulated interleukin-17A and increased colony-stimulating factor 3 in bronchoalveolar lavage fluid (BALF), while WT mice did not. In addition, TLR4 deficiency robustly suppressed the expression of NOD-like receptor family pyrin domain containing 3 and NLR family CARD domain containing 4, decreased caspase-1 activity in TDI-exposed mice, but had no effect on the level of high mobility group box 1 in BALF. Flow cytometry revealed that TDI hampered both neutrophil and eosinophil apoptosis, of which neutrophil apoptosis was further inhibited in TDI-exposed TLR4−/− mice, with marked up-regulation of Bcl-2. Moreover, inhibition of Bcl-2 with either ABT-199 or ABT-737 significantly alleviated neutrophil recruitment by promoting apoptosis. Conclusions These data indicated that TLR4 deficiency promoted neutrophil infiltration by impairing its apoptosis via up-regulation of Bcl-2, thereby resulting in deteriorated AHR and airway inflammation, which suggests that TLR4 could be a negative regulator of TDI-induced neutrophilic inflammation.

Purpose: Accumulating evidence has suggested that toll-like receptor 4 (TLR4) is critically involved in the pathogenesis of asthma. The aim of this study was to investigate the role of TLR4 in toluene diisocyanate (TDI)-induced allergic airway inflammation. Methods: TLR4−/− and wild-type (WT) C57BL/10J mice were sensitized and challenged with TDI to generate a TDI-induced asthma model. B-cell lymphoma 2 (Bcl-2) inhibitors, ABT-199 (4 mg/kg) and ABT-737 (4 mg/kg), were intranasally given to TDI-exposed TLR4−/− mice after each challenge. Results: TDI exposure led to increased airway hyperresponsiveness (AHR), granulocyte flux, bronchial epithelial shedding and extensive submucosal collagen deposition, which were unexpectedly aggravated by TLR4 deficiency. Following TDI challenge, TLR4−/− mice exhibited down-regulated interleukin-17A and increased colony-stimulating factor 3 in bronchoalveolar lavage fluid (BALF), while WT mice did not. In addition, TLR4 deficiency robustly suppressed the expression of NOD-like receptor family pyrin domain containing 3 and NLR family CARD domain containing 4, decreased caspase-1 activity in TDI-exposed mice, but had no effect on the level of high mobility group box 1 in BALF. Flow cytometry revealed that TDI hampered both neutrophil and eosinophil apoptosis, of which neutrophil apoptosis was further inhibited in TDI-exposed TLR4−/− mice, with marked up-regulation of Bcl-2. Moreover, inhibition of Bcl-2 with either ABT-199 or ABT-737 significantly alleviated neutrophil recruitment by promoting apoptosis. Conclusions These data indicated that TLR4 deficiency promoted neutrophil infiltration by impairing its apoptosis via up-regulation of Bcl-2, thereby resulting in deteriorated AHR and airway inflammation, which suggests that TLR4 could be a negative regulator of TDI-induced neutrophilic inflammation.

Although the internal mammary is the lymphatic drainage site for breast cancer, whether postoperative radiotherapy needs to be irradiated remains controversial. In recent years, several random studies have discussed internal mammary radiotherapy to varying degrees and no evidence has obtained that internal mammary radiotherapy bring clinical benefits to overall survival. In clinical practice, internal mammary prophylactic radiotherapy should maintain the balance among the risk of tumor recurrence, prescription dose and radiotherapy techniques to avoid the increased risk of radiotherapy-related death that offsets the possible survival benefits.

Objective:To explore the characteristics of cognitive function in patients with early onset and adult onset schizophrenia.Methods:In this cross-sectional study, 546 patients with schizophrenia who met the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-Ⅳ) were selected.Among them, 62 cases were defined as early onset schizophrenia (EOS, age of onset＜18 years) and 175 patients were defined as adult onset schizophrenia (AOS, age of onset≥25 years).Patients underwent clinical assessments with the Positive and Negative Symptom Scale (PANSS) and the Personal and Social Performance Scale (PSP), and comprehensive neuropsychological assessments.Results:The EOS patients got lower scores in motor function-PEGDOM T score [ (26±12) vs. (30±11), P＜0.01], working memory-average T score of PASAT and WMSSP[ (34±12) vs. (38±10), P＜0.05]and executive function (inhibition) -Stroop T score [ (35±12) vs. (39±10), P＜0.05]than AOS patients.No differences were fund in processing speed, verbal memory and learning, visual memory and learning (Ps＞0.05) between the two groups.Conclusion:It suggests that the EOS patients have worse motor function, working memory and inhibition.

Objective? To understand the situation of urinary incontinence and quality of life among patients with post-laparoscopic radical prostatectomy and to analyze the correlation between them. Methods? From September 2015 to October 2016, we selected 115 patients with post-laparoscopic radical prostatectomy at a ClassⅢ Grade A hospital in Beijing for survey by questionnaire with the method of convenience sampling. We collected patients' general information as well as disease information, and evaluated the situation of urinary incontinence (incidence and severity of urinary incontinence) with the International Consultation on Incontinence Questionnaire-Urinary Incontinence Short Form (ICIQ-UI SF) and influence of urinary incontinence on quality of life with the Incontinence Impact Questionnaire (IIQ-7) to analyze the correlation between severity of urinary incontinence and quality of life. Results? Among 115 patients with post-laparoscopic radical prostatectomy, there were 95 (82.6%) urinary incontinence patients including 41 cases (43.1%) with mild urinary incontinence, 47 cases (49.5%) with medium urinary incontinence and 7 cases (7.4%) with severe urinary incontinence. The score of severity of urinary incontinence ranged from 0 to 19.0 with 8.0 for the median and 5.0 for the interquartile range. Spearman correlation analysis showed that the score of IIQ-7 had a positive correlation with the severity of urinary incontinence (r=0.674, P＜0.01), and had a negative correlation with the postoperative time (r=-0.215, P＜0.05). Multiple linear regression analysis showed that the main influencing factor of quality of life was severity of urinary incontinence (P＜0.01). Conclusions? Urinary incontinence is common among patients with post-laparoscopic radical prostatectomy mainly in mild and medium urinary incontinence. The more serious the urinary incontinence is,the greater the influence on quality of life is which points out that the scientific and effective management by medical staff for urinary incontinence can improve patients' quality of life.

Objective To study the effect of deep inspiration breath-hold(DIBH)technique on the heart dose in whole breast irradiation(WBI)for left breast cancer after breast-conserving surgery, and to investigate the anatomical factors for heart dose. Methods Fifteen patients with left breast cancer who received WBI after breast-conserving surgery and met breathing control requirements were prospectively enrolled as subjects. Simulated CT scans were performed during free breathing(FB)and DIBH. The WBI plans were optimized based on DIBH images.The position,volume,and radiation doses to the heart and lung were compared between the status of FB and DIBH. Correlation of heart dose with various anatomical factors was analyzed in FB status. Between-group comparison of categorical data was made by nonparametric Wilcoxon rank test.A two-variable correlation analysis was made by the Pearson method.Results There was no significant difference in heart volume between the status of FB and DIBH(P=0.773).The volume of both lungs was significantly larger in DIBH status than in FB status(P=0.001). The mean and maximum doses and V5-V40for the heart,left anterior descending coronary artery,left ventricle,right ventricle,and left lung were significantly lower in DIBH status than in FB status(all P<0.05). The greater DIBH increased the lung volume,the greater the mean heart dose decreased. In FB status,the left breast volume,heart-to-lung volume ratio,distance between the inferior margins of breast and heart,and maximum heart margin distance showed a linear correlation with heart dose. Particularly, the heart-to-lung volume ratio and maximum heart margin distance were independently correlated with heart dose. Conclusions DIBH technique in WBI for left breast cancer after breast-conserving surgery significantly reduces heart and lung doses compared with FB. Changes in lung volume are the basis for improving the relative anatomical location of the heart. The heart-to-lung volume ratio and maximum heart margin distance may provide a reference for DIBH technique.

Objective To analyze the correlation between treatment time and radiotherapy plan of deep inspiration breath-hold (DIBH) technique for the whole breast irradiation (WBI) in the left breast cancer after breast-conserving surgery,verify the inter-fractional reproducibility of radiotherapy,observe the heart location and dosimetric changes and calculate the effect of DIBH upon the WBI setup error after the surgery.Methods We prospectively enrolled 15 patients with left breast cancer undergoing WBI after breast-conserving surgery,who met the requirement of D1BH.Treatment time was recorded,its correlation with the number of field and monitor unit was analyzed.Inter-fractional setup errors and PTV delineation were calculated using cone beam CT (CBCT).The accuracy of the position and dose of the heart during radiotherapy was verified by the imaging fusion of CBCT and CT images.The variables among groups were analyzed by non-parametric Firedman test.Results The average treatment time of DIBH radiotherapy was 4.6 minutes.The treatment time was correlated with the maximal and total number of sub-fields and total monitor units.During DIBH treatment,the mean cardiac displacement volume was 19.1 cm3(3.8％).The mean cardiac dose difference between CBCT and planning CT was 5.1 cGy,and there was no significant difference in the heart V5-V30.The mean inter-fractional system setup error (∑) and random setup error (σ) in the left-right (x),superior-inferior (y) and anterior-posterior (z) direction were ∑x 1.9 mm,∑y 2.1 mm,∑z 2.0 mm,σx 1.3 mm,σy 1.3 mm,σz 1.4 mm,respectively.The corresponding minimal margins for setup error were 5.7 mm,6.2 mm and 6.0 mm,respectively.Conclusion DIBH for WBI after breast-conserving surgery does not significantly prolong the treatment time.Treatment time is related to treatment plan.DIBH yields high inter-fractional reproducibility and protects the heart.

Objective To investigate the effects of dedicator of cytokinesis 1 (Dock180) knockout on proliferation and apoptosis in rat derived H9C2 cardiomyocytes and their mechanisms.Methods A single guide RNA (sgRNA) targeting rat Dock180 gene was designed and constructed using CRISPR/Cas9 system.A plasmid contained above sgRNA was packaged into lentivirus and selected to knockout Dock180 in the cardiomyocytes.A single clone of cardiomyocyte with Dock180 knockout was established.Cardiomyocytes were divided into negative lentivirus group (Cas9, A group), Dock180 knockout group (B group), Cas9 lentivirus hypoxia group (C group), Dock180 knockout hypoxia group (D group).The expression of Dock180 mRNA was examined by RT-PCR, and relevant proteins were detected by Western blot.The cell proliferation rate of the cardiomyocytes was determined by MTT, and the apoptotic rate was measured by flow cytometry.Results Dock180 mRNA and protein were absent in B andD groups.Compared with A and C groups, p-ERK1/2 and Bcl-2 protein expression and cell proliferation rate were lower in B and D groups respectively (P<0.01), while Bax protein expression and cell apoptosis rate were higher in B and D groups respectively (P<0.05, P<0.01);Compared with A group, Dock180 mRNA and protein, p-ERK1/2 and Bcl-2 proteins and cell proliferation rate were reduced, while Bax protein and cell apoptosis rate were increased in C group(P<0.05,P<0.01).Compared with B group, p-ERK1/2 and Bcl-2 proteins and cell proliferation rate were decreased, while Bax protein and cell apoptosis rate were increased in D group(P<0.05,P<0.01).Conclusions Dock180 knockout with CRISPR/Cas9 can inhibit proliferation and promote apoptosis via p-ERK1/2, Bcl-2 and Bax in H9C2 cardiomyocytes.