ZnS:Mn Quantum Dots Coated with a Silica Molecularly Imprinted Polymer for Trace Teflubenzuron Detection in Vegetable Samples.

A novel nanocomposite fluorescent probe consisting of quantum dots and a silica molecularly imprinted polymer (MIPs-capped ZnS:Mn QDs) was synthesized and applied for the rapid detection of teflubenzuron (TBZ) based on the fluorescence quenching of a composite probe via TBZ. The fluorescence quenching efficiency of MIP@SiO2@ZnS:Mn QDs displayed a linear relationship over the concentration range of 0-26.24 µmol/L with a correlation coefficient of 0.9857 and the limit of detection was 2.4 µg/L. The selectivity test showed that the nanocomposite had good selectively rebind TBZ with higher imprinting factor of 3.06 compared with four structurally similar compounds. In addition, the probe was successfully applied to the detection of TBZ in vegetable samples with a recovery of 90.3~97.1% and with a relative standard deviation below 3.2%. This developed method has the advantages of simple preparation, fast response and low toxicity for trace TBZ detection.

Multifunctional Polyurethane Composite Foam with Outstanding Anti-impact Capacity for Soft Body Armors.

Herein, a multifunctional polyurethane (PU) composite foam with a hierarchical structure is fabricated by dip-coating a carbon nanotube/shear-thickening gel (CNT/STG) and spray-coating nano-SiO2/STG on PU foam. The prepared nano-SiO2/CNT/STG@PU (SCS@PU) composite foam is lightweight, highly compressive, electrically conductive, superhydrophobic, and impact-energy absorptive. As a result, it possesses an excellent sensing ability to compression with a stable response up to 80% strain, an outstanding linearity of R2 > 0.99, and a wide response frequency of 0.01 to 1 Hz; it can also be used for effectively detecting impact force and sensing various human motions. Moreover, the superhydrophobicity with a water contact angle up to 154° of SCS@PU composite foam endows it with an excellent resistance to hazardous liquids (strong acid and alkali) to ensure its service reliability under harsh circumstances. In particular, the SCS@PU exhibits an outstanding anti-impact capability with an impact force attenuation rate of SCS@PU as high as 81%. Finally, its applications as soft body armors are demonstrated in protecting a wearer wearing a helmet with the SCS@PU as liner and using the SCS@PU as a smart kneecap against impact. On consideration of its excellent strain-sensing ability, superhydrophobicity, and outstanding anti-impact capability, the multifunctional SCS@PU composite foam developed is promising for personal safety protection.

[Role of miR-21 in rat hepatic oval cell proliferation and activation].

OBJECTIVE: To investigate the possible mechanisms of miR-21-mediated regulation of proliferation and activation of hepatic oval cells. METHODS: The 2-acetamidofluorene/partial hepatectomy (2-AAF/PH) method was applied to generate hepatic oval cell activation model in male Sprague-Dawley rats; after the 7 days of 2-AAF/PH or PH alone (control), the rats were sacrificed at 0 h, 6 h, 12 h, 24 h, 72 h and 168 h. Expression of miR-21 was detected by real-time PCR and differences between groups were evaluated using the two-sample t-test. Differential transcription of miR-21 target genes was assessed bioinformatically, and with western blotting to detect changes in protein expression of the target gene. RESULTS: The rat hepatic oval cell activation model was successfully established.The 2-AAF/PH rats showed miR-21 expression beginning to increase at 12 h, peaking at 24 h, and decreasing thereafter until an increase at 168 h.For the control group, the miR-21 expression began to increase at 6 h, until 24 h when expression began steadily declining to reach the original level.Compared to the control group, the experimental group showed expression of miR-21 that was significantly less at 6 h (P=0.039, t =3.029) and significantly more at 24 h and 168 h (P=0.026, t =-3.433 and P=0.007, t =-5.105). Among the predicted target genes of miR-21 were WW domain containing E3 ubiquitin protein ligase 1 (WWD), Smad family member 7 (Smad7), and polybromo-1 (Pbrm1).Smad7 protein expression began to decrease at 6 h in the control group, until reaching its minimum at 24 h when it increased; in the experimental group, SMAD7 expression increased at 6 h, then began to decrease with the minimum detected at 168 hour.In the control group, the Smad7 mRNA expression decreased slightly at 6 h, then began to increase, reaching its peak at 24 h when the expression fell to the original level. In the experimental group, the Smad7 mRNA expression began to increase at 6 h and reached its peak at 24 h when it decreased; the expression was little more than its original level at 168 h.Smad7 protein expression was negatively correlated with miR-21, and Smad7 mRNA expression was positively correlated with miR-21 but negatively correlated with Smad7 protein expression. CONCLUSION: miR-21 may play a vital role in the activation and proliferation of hepatic oval cells.As a target gene of miR-21, Smad7 might be involved in the process.

Undifferentiated embryonal liver sarcoma in childhood: A case report.

In order to improve the diagnosis and therapy of undifferentiated embryonal liver sarcoma (UELS), the present study presents the case of a 9-year-old female with UELS and discusses UELS in childhood. The patient presented with abdominal pain and fever. The laboratory tests, radiographic examination and pathological features presented by the female were similar to those of typical cases of UELS reported in childhood. The patient initially received surgical treatment and the immunohistochemical findings suggested that the patient had UELS. The patient's parents refused adjuvant chemotherapy and demonstrated a right prerenal mass 6 months post-surgery. Microscopic examination revealed that the tumor was evidence of undifferentiated embryonal sarcoma recurrence. However, the patient was comfortable and physical examination revealed no abnormal conditions. In addition, the laboratory results were normal. Abdominal computed tomography scan and ultrasound were performed every 3 months to monitor the tumor recurrence. At the time of writing, it has been 6 months after the second surgical procedure and there has been no appearence of abnormalities. Previous studies have shown that patients who receive combined therapy with complete tumor resection and adjuvant chemotherapy have a longer survival time than those who undergo surgical therapy alone. Complete tumor resection combined with adjuvant chemotherapy may reduce the risk of recurrence and enhance the survival time in patients with UELS.

Correlation between tuberous sclerosis complex 2 and glycogen synthase kinase 3 beta levels, and outcomes of patients with hepatocellular carcinoma treated by hepatectomy.

AIM: Tuberous sclerosis complex 2 (TSC2), a tumor suppressor, may play an essential role in the regulation of cell growth and cell survival under energy stress conditions. In addition, TSC2 may act in concert with Wnt and energy signals by additional phosphorylation of glycogen synthase kinase 3ß (GSK3ß) to regulate cell growth. The expression levels and function of TSC2 and GSK3ß in hepatocellular carcinoma (HCC) remain unclear. METHODS: The protein levels of TSC2 and GSK3ß were measured by immunohistochemistry in normal liver (n = 20), HCC (n = 80) and pericancerous tissues (n = 80). The correlations between TSC2, and GSK3ß levels, clinicopathological features and patient survival were also analyzed. RESULTS: The protein levels of TSC2 and GSK3ß in HCC tissues were significantly lower than that in normal liver tissues and pericancerous tissues (P < 0.05). Decreased TSC2 and GSK3ß expression was found to be significantly correlated with advanced clinicopathological characteristics and poor prognosis. The results also showed that TSC2 protein levels were associated with GSK3ß expression in HCC specimens. CONCLUSION: This is the first demonstration that the decreases in TSC2 and GSK3ß levels may be associated with vascular invasion, histological grade and tumor-node-metastasis classification.

Decreased expression of LKB1 correlates with poor prognosis in hepatocellular carcinoma patients undergoing hepatectomy.

AIM: To study any correlation of LKB1 expression with prognosis in hepatocellular carcinoma (HCC) cases. METHODS: A total of 70 HCC patients and 20 primary intrahepatic stone patients in the first affiliated hospital of Wenzhou Medical College were enrolled in this study. LKB1 expression was detected by immunohistochemistry. Patients were followed-up and prognostic factors were evaluated. RESULT: LKB1 expression was decreased in the HCC samples. Loss of LKB1 expression in HCC was significantly related to histologic grade (P=0.010), vascular invasion (P=0.025) and TMN stage (P=0.011). Patients showing negative LKB1 expression had a significantly shorter disease-free and overall survival than those with positive expression (P = 0.001, P=0.000, respectively). Multivariate Cox regression analysis indicated that LKB1 expression level was an independent factor of survival (P = 0.033). CONCLUSION: HCC patients with decreased expression LKB1 have a poor prognosis. The loss of LKB1 expression is correlated with a lower survival rate.

Energy-band engineering for improved charge retention in fully self-aligned double floating-gate single-electron memories.

We present a new fully self-aligned single-electron memory with a single pair of nano floating gates, made of different materials (Si and Ge). The energy barrier that prevents stored charge leakage is induced not only by quantum effects but also by the conduction-band offset that arises between Ge and Si. The dimensions and position of each floating gate are well-defined and controlled. The devices exhibit a long retention time and single-electron injection at room temperature.