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Owing to the rising concerns about environmental degradation worldwide, firms in several developed and developing countries are pursuing carbon emission reduction targets. In addition, in recent years, there is evidence of a shift in consumer preferences in favour of low-carbon products. Using a theoretical model, where the shift in consumer preferences is explicitly incorporated, we evaluate the impact of carbon emission reduction cost-sharing on supply chain profit. In our model, consumers are willing to pay a higher price for low-carbon products and hence the retailer considers sharing the cost of carbon emission reduction with the manufacturer. Our model also includes a carbon trading mechanism. We identify a range of carbon emission reduction cost-sharing such that both supply chain enterprises are better-off. We find that, while achieving the aim of carbon emission reduction, consumer preference for low-carbon products can benefit both supply chain enterprises. Numerical simulations show that carbon emission reduction cost-sharing increases the retailer’s order quantity as well as the profit and hence there is an incentive for the two supply chain enterprises to cooperate.

Owing to the rising concerns about environmental degradation worldwide, firms in several developed and developing countries are pursuing carbon emission reduction targets. In addition, in recent years, there is evidence of a shift in consumer preferences in favour of low-carbon products. Using a theoretical model, where the shift in consumer preferences is explicitly incorporated, we evaluate the impact of carbon emission reduction cost-sharing on supply chain profit. In our model, consumers are willing to pay a higher price for low-carbon products and hence the retailer considers sharing the cost of carbon emission reduction with the manufacturer. Our model also includes a carbon trading mechanism. We identify a range of carbon emission reduction cost-sharing such that both supply chain enterprises are better-off. We find that, while achieving the aim of carbon emission reduction, consumer preference for low-carbon products can benefit both supply chain enterprises. Numerical simulations show that carbon emission reduction cost-sharing increases the retailer's order quantity as well as the profit and hence there is an incentive for the two supply chain enterprises to cooperate.

The benefit of adjuvant chemotherapy (AC) in locoregionally advanced nasopharyngeal carcinoma (NPC) is controversial. This study compared concurrent chemoradiotherapy plus AC (CCRT/AC) with CCRT. Pair-matched analysis based on eight clinicopathological features of 244 patients treated with platinum-based CCRT/AC or CCRT alone was performed. Survival outcomes were assessed using the Kaplan–Meier method and log-rank test. Toxicities and response rates were compared using Fisher’s exact test. Four-year overall survival, progression-free survival, distant failure-free survival, and locoregional failure-free survival were 72 %, 61 %, 71 %, and 81 %, respectively, for the CCRT arm, compared to 74 % (hazard ratio, HR 0.89; 95 % confidence interval, CI 0.64–1.23; P = 0.474), 62 % (HR 0.91, 95 % CI 0.68–1.20, P = 0.489), 73 % (HR 0.84, 95 % CI 0.59–1.18, P = 0.316), and 84 % (HR 0.84, 95 % CI 0.52–1.24, P = 0.323), respectively, for the CCRT/AC arm. Cox multivariate regression analysis demonstrated AC was not an independent prognostic factor. Overall, there was a higher incidence of grade 3–4 toxicities in the CCRT/AC arm. The most common grade 3–4 adverse events in the CCRT/AC arm were vomiting (27 %), nausea (43 %), leukopenia/neutropenia (23 %), thrombocytopenia (8.8 %), and anemia (6.2 %). Addition of AC to CCRT increased toxicities but did not improve survival in locoregionally advanced NPC.

To investigate the correlation of CD4Fifty-nine patients with NSCLC treated with radical surgery were followed up for 5 years. Blood Treg cells were examined during the follow-up using flow cytometry (FCM). The sensitivity and specificity of Treg cells to predict recurrence of NSCLC were analyzed using receiver-operating characteristic (ROC) curve and compared with those of carcinoembryonic antigen (CEA) and cytokeratin21-1 (Cyfra21-1). The influences of gender, age, occupation and radiotherapy on survival time of the patients were analyzed with Kaplan-Meier method.Among the 59 patients, the shortest survival time was 23 months while the longest time was over 67 months. Nineteen patients had NSCLC recurrence, and 17 (28.81%) of them died of metastasis during the follow-up. The frequencies of blood Treg cells in patients who did not receive radiotherapy and in patients with tumor recurrence were significantly higher than those in patients receiving radiotherapy and in patients free of recurrence (P=0.000). ROC curves showed that the area under curve (AUC) lowered in the order of Treg cells, Cyfra21-1, CEA (P=0.002, 0.006 and 0.013, respectively) with 95% confidence interval (CI) of 0.649-0.981, 0.621-0.936 and 0.584-0.944, respectively. At the cut-off value of 7.53%, the sensitivity and specificity of Treg cells to predict NSCLC recurrence was 91.42% and 87.59%, respectively. The five-year survival rate of the 59 patients was 71.18% (42/59), and Kaplan-Meier analysis revealed a longer survival time in female patients (P=0.038), in patients below 50 years of age (P=0.013), in patients not engaging in mental work (P=0.029), and in patients receiving radiotherapy (P=0.003).Treg cells has a better efficiency than Cyfra21-1 and CEA to predict tumor recurrence in patients with NSCLC following radical surgery. The male gender, an age beyond 50 years, an occupation of mental work, and failure to receive radiotherapy are all risk factors for recurrence of NSCLC.

The purpose of this study was to test whether the insulin sensitivity, lipid metabolism and the susceptibility of the heart to ischemia/reperfusion injury are modulated by the chronic estrogen status. Rats were ovariectomized (OVX), not ovariectomized (sham) or ovariectomized and treated with subcutaneous 17 -estradiol (30 mug/kg/day, OVX+E2) (n=14-17 per group). Within 3 months after operation, body weight, the serum levels of estrogen, glucose, insulin, total cholesterol (T-chol), HDL-chol, LDL-cholesterol (LDL-chol), triglycerides (TG) and lipoprotein a (Lp(a)) were monitored. Three months after operation, hearts of partial rats (n=6-8 per group) were isolated and allowed an initial 20-min stabilization period, and then cardiac function was recorded and creatine kinase (CK) release in the coronary effluent was measured after 4 h of hypothermic ischemia in isolated rat hearts. The experimental results showed that from 2 weeks after ovariectomy to the end of the study, body weights of OVX were significantly higher compared with the other two groups (p0.05). On weeks 5 and 9, insulin level of OVX was significantly higher than that of the other two groups (p0.05), whereas it was not different among the three groups on weeks 12 and 13 (p0.05). Blood glucose on week 13 was significantly higher in OVX (p0.05). Consequently, Insulin Sensitivity Index (ISI) of OVX was lower than that of the other two groups on weeks 5 and 9 (p0.05), but not on weeks 12 and 13. Serum values for T-chol, HDL-chol and LDL-chol were not significantly different among the three groups within the observing period. On week 13, TG level in ovariectomized group was significantly lower than in the sham- and E2-treated groups (p0.05). Compared with sham, Lp(a) level was slight increased in OVX rats (p0.05), while it was further increased in E2-treated rats (p0.05). Cardiac function (left ventricular pressure (LVP) and +/-dp/dtmax) of hearts removed from OVX rats was depressed, and CK release was markedly increased (p0.05). However, treatment with E2 significantly improved cardiac function, as shown by increasing left ventricular pressure,+dp/dtmax and -dp/dtmax, and decreased CK release. In conclusion, chronic E2 treatment has some beneficial effects on cardiovascular disease (CVD), which come from the results of improvement of insulin sensitivity and post-ischemia cardiac function. However, the mechanism did not include changes in lipids and lipoproteins. The change in Lp(a) level shows that estrogen does not confer cardiovascular protection and may increase the risk of stroke.

Dehydroepiandrosterone (DHEA), a precursor of androgens and estrogens, has been demonstrated to have effect of preventing insulin resistance and development of diabetes mellitus. Administration of testosterone appears to induce a marked insulin resistance. How these two hormones affect insulin resistance through regulation of sensitivity of tissues to insulin deserves further studies. Here, the effects of DHEA and testosterone on response to insulin in C2C12 muscle cells are analyzed. After 24 h of DHEA (10−6 mol/L) treatment, C2C12 cells showed an increased insulin- stimulated glucose uptake and enhanced activities of glycogen synthase (GS),phosphofructokinase (PFK) and pyruvate dehydrogenase (PDH), whereas testosterone gave the opposite effects. Incubation of C2C12 cells with high-dose insulin (5 × 10−7 mol/L) for 24 hours decreased their sensitivity to insulin and led to a state of resistance as assessed on insulin-stimulated glucose uptake and activities of GS, PFK and PDH. Addition of DHEA t...

The purpose of this prospective study is to investigate the predictive and prognostic significance of the Raf kinase inhibitory protein (RKIP) in locoregionally advanced nasopharyngeal carcinoma (NPC). Immunohistochemical assays were performed to detect the RKIP protein expression of samples from 212 patients with locoregionally advanced NPC. All patients were assigned randomly into the inductive chemotherapy plus radiation therapy (IC + RT) group, the concurrent chemoradiotherapy (CCRT) group, the inductive chemotherapy plus concurrent chemoradiotherapy (IC + CCRT) group, and the radiation therapy alone (RT) group. The patients in the IC + RT group were treated with IC using 2-3 cycles of cisplatin (80 mg/m(2)) and fluorouracil (500 mg/m(2)), repeated every 3 weeks, followed by radiotherapy. Those in the CCRT group were treated with weekly cisplatin (40 mg/m(2)) for 6-7 cycles during radiotherapy. In the IC + CCRT group, the chemotherapy prior to radiation was similar to the cisplatin-fluorouracil regimen in the IC + RT group, whereas it cisplatin regimen was identical to that in the CCRT group. The results show that RKIP is an independent prognostic factor for 5-year distant metastasis-free survival (DMFS), overall survival (OS), and progression-free survival (PFS). Patients with high RKIP expression benefited more from reduced metastasis in the IC + RT and the IC + CCRT group, with improved OS and PFS in each treatment group compared with that among patients with low RKIP expression. In the high RKIP expression subgroup, chemotherapy combined with radiotherapy improved the DMFS when compared with the RT group, but this effect was not observed in the low RKIP expression subgroup. RKIP was predictive of distant metastasis with good sensitivity and specificity. Clinically, high RKIP expression inhibited distant metastasis in advanced NPC, and its detection might be used to predict distant metastasis with good sensitivity and specificity. The effect of chemotherapy on distant metastasis in combined chemoradiotherapy might be related to the RKIP expression level. Patients with high RKIP expression showed more improved OS and PFS than their low RKIP expression counterparts. Higher RKIP expression improves the DMFS of patients who receive inductive high-dose cisplatin-based chemoradiotherapy, with or without concurrent cisplatin. Low RKIP expression is also a predictive marker for cancer progression and metastasis, which could be used to stratify patients with high risk of metastasis and death.

The purpose of this study was to determine whether the renin-angiotensin system (RAS), nitric oxide (NO), atrial natriuretic peptide (ANP), blood pressure (BP), ultrastructural characteristics, and endothelium-dependent relaxation of thoracic aorta were modulated by the estrogen level. Rats were divided into 3 groups: ovariectomized (OVX); not ovariectomized (sham); and ovariectomized and treated with subcutaneous 17beta-estradiol (15 microg/kg/day, OVX+E(2)) (n=15-17 per group). For 13 weeks after surgery, blood pressure, serum estrogen, NO, plasma angiotensin II (Ang II), ANP, and renin activity levels were monitored. Thirteen weeks after surgery, the vasodilator responses of the aortic rings to acetylcholine and the ultrastructural characteristics of the thoracic aorta were determined. In the 9th and 13th week, OVX rats had a significantly higher blood pressure than the other two groups (p0.05). Ovariectomy led to a significant decrease in plasma Ang II level and a significant increase in renin activity in OVX rats compared to sham rats; this effect could be reversed by estrogen treatment. In the 5th, 9th, and 13th weeks, the serum NO level was significantly lower in the OVX group than in the sham group (p0.05); this effect could be reversed by estrogen treatment. Plasma ANP levels in the 9th and 13th weeks were significantly lower in the OVX group (p0.05), and plasma ANP levels could be completely restored by estrogen treatment. Ovariectomy markedly reduced endothelium-dependent relaxation in response to acetylcholine in isolated rat thoracic aortic rings; chronic estrogen treatment significantly restored endothelium-dependent relaxation in response to acetylcholine. Under electron microscopy, the endothelial cells in OVX rats were swollen, even necrosed; estrogen treatment inhibited these changes. These results strongly suggest that estradiol protects rats from the development of hypertension and has a protective effect on the endothelium by increasing NO and ANP levels while decreasing renin activity. However, there was a discordance between the effects that estradiol had on angiotensin II and on blood pressure. This might be the result of negative feedback that ultimately results in the overall suppression of the RAS.

AIM: To establish a model of islet-ductal cell transdifferen-tiation to identify the transdifferentiated cells. METHODS: Collagen was extracted from rat tail at first. Purified rat islets were divided into three groups, embedded in collagen gel and incubated respectively in DMEM/F12 alone (control group), DMEM/F12 plus epidermal growth factor (EGF), DMEM/F12 plus EGF and cholera toxin (CT). Transdifferentiation was proved by microscopy, RT-PCR, immunohistochemistry and RIA. RESULTS: Islets embedded in collagen gel plus EGF and CT were cystically transformed and could express new gene cytokeratin 19 while still maintaining the expression of insulin and Pdx-1 genes. Immunohistochemistry demonstrated that the protein of cytokeratin 19 was only expressed in the third group. The insulin content secreted by islets in the third group decreased significantly during the transdiffe-rentiation. CONCLUSION: CT is a crucial factor for the islet-ductal cell transdifferentiation.

To investigate the effects of long-term estrogen replacement treatment (ERT) on the expression of bcl-2 and H-ras in rat endometrium.Thirty 5-month-old SD female rats were randomly divided into 3 groups: Control group ( sham operated and vehicle injected, n 10) , OVX group (OVX operated and vehicle injected, n = 10) , and ERT group (OVX operated and 17 beta-estradiol injected, n = 10). The rats were killed in the 13th week and the uteri were isolated and weighed, pathologically analyzed, and we measured the thickness of the endometrium. Immunochemistry and in situ hybridization analysis were used to examine the changes of bcl-2 and H-ras mRNA and Bcl and H-ras protein expression in the endometrium of the rats.Uterine weight and endometrial thickness of OVX decreased much more than those of the control (P0.01 ) and ERT rats (P0.01). One simple hyperplasia and one squamous metaplasia of endometrium were found in ERT rats. Quantitatively, bcl-2 and H-ras mRNA and Bcl and H-ras protein level of ERT were higher than those of OVX rats (P0.01 ), and there were no statistical significances between the ERT group and the control rats.Long-term estrogen replacement can keep the endometrium from atrophy, and lead to the genesis of simple hyperplasia and squamous metaplasia of the endometriun, which can increase the risk of endometrial carcinomas. Estrogen may inhibit apoptosis and promote the proliferation of endometrial cells through increasing the expression of bcl-2 and H-ras mRNA and Bcl-H-ras proteins.

To determine the effects of long-term estrogen replacement treatment on blood pressure and expressions of insulin receptor (IR) and insulin receptor substrate-1 ( IRS-1) in myocardium.Fifty female SD rats were randomly divided into 3 groups. And then sham ( n = 16), ovariectomy (OVX, n = 17), and estrogen replacement treatment group (OVX + E2, n = 17) were established. Systolic blood pressure of tail artery was determined by tail-cuff technique before the operation and on week 12 after the operation. The expressions of IR and IRS-1 were measured by RT-PCR in myocardium of SD rats.Blood pressure [ (118.75+/-2.77) mmHg] in OVX was significantly higher than that in the sham [ ( 103.86+/-1.84) mmHg, P0.05 ] and OVX + E2 [( 107.83+/-3.24) mmHg, P0.05 ] rats. Expression of IRS-1 in OVX group was significantly lower ( 1.2588+/-0.1045)than that in the sham(2.2089+/-0.0988, P0.05) and OVX + E2 groups ( 1.9100+/-0.1230, P0.05 ). However, there was no difference on blood pressure and expression of IRS-1 between sham and OVX + E2 groups (P0.05 ). The difference of IR expression has no statistical significance among the 3 groups.Long-term estrogen replacement treatment might protect cardiovascular system through decreasing the blood pressure and inducing the expression of IRS-1 in myocardium. However, plasma estrogen level doesn't significantly influence the IR expression.

Insulin receptor substrate-2(IRS-2) belongs to a family of cytoplasmic adaptor proteins, which link insulin, insulin-like growth factor-1(IGF-1), and cytokine receptor tyrosine kinases to signaling pathways regulating metabolism, growth, differentiation, reproduction, and homestasis. Deficiency of IRS-2 in mice causes type 2 diabetes mellitus (T2DM), suggesting that abnormal structure and dysfunction of the IRS-2 gene may contribute to the pathogenesis of T2DM. Variations in the open reading frame (ORF) and promoter region of IRS-2 gene in patients with T2DM have been reported over the past few years. These genetic variations are from ethnically different patients, confounding any analysis of the contribution of IRS-2 gene variations to the development of T2DM. The 3'-untranslated region(3'-UTR) of IRS-2 gene variation may be contribute to the T2DM. So far, the relationship between 3'-UTR of IRS-2 gene variations and T2DM have not been investigated. Based on the 3'-UTR of eukaryotic gene plays an important role in the eukaryotic gene regulation, we investigated abnormalities of IRS-2 gene 3'-UTR and their relation with T2DM in the Chinese population. Genomic DNA was extracted from leukocyte of 128 patients with T2DM and 125 control subjects in Hunan, China. A segment of IRS-2 gene 3'-UTR was scanned by polymerase chain reaction (PCR)-denaturing high-performance liquid chromatography (DHPLC). All PCR products with abnormal DHPLC pattern were submitted to DNA sequence analysis. A T--C mutation at 4064 bp of IRS-2 gene 3'-UTR was found in 18 patients with T2DM, while it was only found in 5 control subjects. The incidence of the mutation in patients with T2DM were much higher than that in contol subjects (14.1% vs 4.0%, x2 = 7.748, P = 0.005). These results indicate that the T4064--C in IRS-2 gene 3'-UTR may be related to Chinese patients with T2DM.

To study the genetic variation in 5'-regulatory region of aldose reductase (AR) gene that might influence expression and the relationship between variations and diabetic complication (DC), PCR-single stranded conformational polymorphism (SSCP) was used to screen the 5'-regulatory region of AR gene in Chinese patients with type 2 diabetes mellitus. A novel mutation, C(-167) --A substitution which created a new CCAAT box was found only in two diabetic patients. These two patients have no retinopathy, and the AR activity of their erythrocytes was within low range in patients without DC. The DNA segments of AR wild type and mutant were subcloned into pCAT reporter vector, and CAT assays were performed to assess promoter activity. The interaction between the DNA segments and nuclear proteins was determined by using competitive gel electrophoretic mobility shift assay (EMSA). The transcriptional activity of mutant (5.7% +/-2.9%) was lower than that of wild type (15.7% +/- 4.1%) (P0.01), and the mobility shift of mutant was also slower than that of wild type. The results indicated the mutation C(-167) --A in AR gene might prevent or delay the development of DC by repressing the expression of AR gene.

1. Many clinical studies have suggested a relationship between oestrogen and insulin sensitivity. In the present study, HepG2 cells were divided into four groups: (i) control, incubated with 1 nmol/L insulin; (ii) the HI group, which was incubated with 100 nmol/L insulin to induce insulin resistance; (iii) the E2 group, in which control cells were incubated with 1 nmol/L insulin plus 1 nmol/L oestradiol; and (iv) the HI + E2 group, in which insulin-resistant cells were incubated with 100 nmol/L insulin + 1 nmol/L oestradiol. 2. A high concentration of insulin decreased the activity of phosphofructo-1-kinase (PFK), pyruvate dehydrogenase (PDH) and glycogen synthase (GS), as well as decreasing the expression of insulin receptor (IR) and insulin receptor substrate-2 (IRS-2). High insulin had no effect on glucose transport or the expression of insulin receptor-1 (IRS-1). 3. The addition of oestradiol to control cells increased glucose transport, the activity of PFK, PDH and GS and the expression of IRS-1 and IRS-2, but had no effect on the expression of IR. 4. Treatment of insulin-resistant HepG2 cells with oestradiol attenuated HI-induced decreases, except for IR, and the expression of IRS-1 was significantly higher than control, attaining levels seen in group 3. The expression of IRS-2 was significant higher than in insulin-resistant cells, but did not reach control levels. Changes in the activity of PFK, PDH and GS were the same as the changes seen in the expression of IRS-2. 5. These results suggest that high concentrations of insulin induce insulin resistance in HepG2 cells, whereas oestradiol improves glucose metabolism and insulin signal transduction of cells by enhancing the activity of key enzymes involved in glucose metabolism and the expression of IRS-1 and IRS-2.