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The construction of "smart" materials able to perform specific functions at the molecular scale through the application of various stimuli is highly attractive but still challenging. The most recent applications indicate that the outstanding flexibility of self-assembled architectures can be employed as a powerful tool for the development of innovative molecular devices, functional surfaces and smart nanomaterials. Structural flexibility of these materials is known to be conferred by weak intermolecular forces involved in self-assembly strategies. However, some fundamental mechanisms responsible for conformational lability remain unexplored. Furthermore, the role played by stronger bonds, such as coordination, ionic and covalent bonding, is sometimes neglected while they can be employed readily to produce mechanically robust but also chemically reversible structures. In this review, recent applications of structural flexibility and molecular motions in self-assembled nanostructures are discussed. Special focus is given to advanced materials exhibiting significant performance changes after an external stimulus is applied, such as light exposure, pH variation, heat treatment or electromagnetic field. The crucial role played by strong intra- and weak intermolecular interactions on structural lability and responsiveness is highlighted.

Carboxylatopillar[5]arene (CP[5]A), a new water-soluble macrocyclic synthetic receptor, has been employed as a stabilizing ligand for in situ preparation of gold nanoparticles (AuNPs) to gain new insights into supramolecular host-AuNP interactions. CP[5]A-modified AuNPs with good dispersion and narrow size distributions (3.1 ± 0.5 nm) were successfully produced in aqueous solution, suggesting a green synthetic pathway for the application of AuNPs in biological systems. Supramolecular self-assembly of CP[5]A-modified AuNPs mediated by suitable guest molecules was also investigated, indicating that the new hybrid material is useful for sensing and detection of the herbicide paraquat.

A new drug delivery system, based on mesoporous silica nanoparticles gated by carboxylatopillar[5]arene-modified gold nanoparticles, has been fabricated, which demonstrated good responses to competitive binding and temperature variation. This multifunctional nanosystem combines the excellent characteristics of two kinds of nanoparticles and utilizes a supramolecular host–guest approach for on-demand cargo release.

[m]Bp-ExPn with a rigid and nanometer-sized cavity, as an extended version of pillar[n]arene by replacing 1,4-dimethoxybenzene monomers with biphenyl entities, was synthesized for the first time. Intriguingly, toluene and m-xylene can be stably included within the cavity of [2]Bp-ExP6, which endows these newly developed synthetic receptors with great potential in the purification of petrochemicals.

Purpose. To study ocular surface temperature (OST) in dry eyes by static and dynamic measures.Methods. OST was recorded on 62 dry eyes and 63 age- and sex-matched controls. Static measures were study of absolute OST att=0, 5, and 10 s after eye opening. Dynamic measures were study of mean change and net change in OST over 10 s of sustained eye opening. Ten OST indices studied were temperatures of the geometric center of the cornea (GCC), extreme temporal (T1) and nasal conjunctiva (T4), midtemporal (CT) and nasal conjunctiva (CN), temporal (LT) and nasal (LN) limbus, and mean (MOST), maximum (Max T), and minimum (Min T) temperatures of the region of interest.Results. For static measures, dry eyes recorded significantly lower GCC, MOST,Min T,Max T, T4, CT, LT, LN, and CN. For dynamic measures, dry eyes had significantly steeper regression line of mean change (corresponding to greater net change) forMax T5 s onward and T4 at 3 s onward.Conclusions. Both static and dynamic measures of the OST were valuable and can be used as clinical tool to assess dry eye.

Objective: To study the diagnostic ability of conventional dry eye tests and their correlation with ocular surface temperature (OST) and derive the best combined objective tests for dry eye. Methods: This was a single visit study included a few conventional dry eye tests on 62 dry eye and 82 control subjects: symptom evaluation, fluorescein break-up time (FBUT), corneal epithelial staining (CES), non-invasive break-up time (NIBUT) and tear meniscus height (TMH). OST was recorded using NEC TH9260 thermo tracer and six temperature metrics of the extreme nasal conjunctiva was studied including the temperature 10 seconds after eye opening (T4-10). Diagnostic ability was assessed by calculating sensitivity and specificity and area under the receiver operating characteristics curve (AUC). Results: No correlation (Pearson's coefficient, -0.203 to 0.209; p>0.05) was found between Mscore, Scount, FBUT and CES with any of the temperature metrics. However, CES correlated significantly with TMH (r=0.276; p=0.030) and inversely correlated significantly with FBUT (r=- 0.258; p=0.043). Values of Mscore at 8 were found to give sensitivity of 87.1% (95% CI: 76.2 to 94.3%) and specificity of 92.7% (84.8 to 97.3%). Values of Scount at 1 were found to give sensitivity of 93.6% (84.3 to 98.2%) and specificity of 65.9% (54.6 to 76.0%). Values of FBUT at 2 s were found to give sensitivity of 58.1% (44.9 to 70.5%) and specificity of 87.8% (78.7 to 94.0%). Values of CES at grade 2 were found to give sensitivity of 71% (58.1 to 81.8%) and specificity of 59.8% (48.3 to 70.4%). Combining CES with T4-10 (series) had increased the AUC to 78% with sensitivity and specificity of 92.3% and 42.7% respectively. Conclusion: This work validated the ability of Mscore, Scount, FBUT and CES in diagnosing dry eye and further confirmed the discordance between its signs and symptoms. Combining CES with T4-10 (series) can be future objective tests for dry eye.

The present chapter reports on recent developments of calixarenes and pillarenes (or pillar[n]arenes) on the surfaces of a variety of different nanoparticles (i.e., gold, silver, quantum dots, Fe3O4, TiO2, Pt, Pd, and Ru), electrodes, devices, porous materials (i.e., mesoporous silica and metal-organic frameworks), and carbon materials. Compared with traditional hybrid materials, these hybrid organic-inorganic nanosystems take advantage of molecular recognition of calixarenes and pillarenes towards guests for the fabrication of nanodevices of nano-micro sizes with optical, mechanical, electrical, catalytic and electrochemical properties. Their splendid applications in recognition, stabilization, self-assembly, dispersion, electrode, controlled drug release, separation and absorption will be covered in this chapter.

Strain Gluconacetobacter hansenii CGMCC1671 and Saccharomyces cerevisiae CGMCC1670 were applied to make traditional Kombucha with pure cultures to search for the optimum parameters of major factors affecting the yields and productivities of Bacterial cellulose (BC) in the beverage. Three culture factors were examined. The yields and productivities of BC and sugar consumed were measured after cultured statically for 22 days. After single factor test factors affecting the yields and productivities of BC have been optimized by response surface methodology (RSM). The quadratic polynomial regression equation reflecting BC yield and affecting factors was build up with Box-Behnken design principle. The optimal values of 10.37% inoculum, initial pH 4.96 and medium volume 77.13 mL in 250 mL flask were obtained with theoretical BC yield 300.093mg/g. BC yield of 279.579 mg/g was obtained with 6.84% deviation by validation test with the optimal parameters. The co-culture of pure strains of traditional Kombucha technique can be used to provide both high quality and high yield of BC in addition to producing high quality Kombucha beverage.

Purpose To investigate the accuracy and sensitivity of the Thermo-Tracer TH9100MV, NEC San-ei in monitoring the temperature of the anterior eye surface and to establish an inter-subjects ocular surface temperature (OST) norm in Chinese young adults. Methods A blackbody with fixed temperature was used to study accuracy and sensitivity of the thermal camera used (Thermo-Tracer TH9100MV, NEC San-ei). Sixty healthy Chinese young adults aged 17–21 (mean age 19) were recruited from the Singapore Polytechnic Optometry Centre. A room with standard room temperature and humidity was used. Subjects were adapted to the room conditions for 20 min before measurement. OST was then measured within 4–5 s after a blink and with their upper lid lifted by a cotton bud, using infrared thermo-camera, in a non-invasive manner. Results All future Thermo-Tracer readings could be converted to ‘true’ temperature via the regression equation derived y = 1.0884x − 3.4026 (r2 = 0.9985), where y is the ‘true’ temperature and x is reading by Thermo-Tracer. Sensitivity of the machine for all 16 temperatures studied was found to be 91.3%. Mean OST for the population studied was 34.70 ± 0.50 °C. Mean OST at geometrical centre cornea (GCC) was 34.39 ± 0.47 °C and inter-ocular temperature difference was ∼0.20 ± 0.15 °C. Both the horizontal and vertical OST profile was established. No significant differences between right/left eyes and between genders were found at 95% CI. Conclusions Findings on the accuracy can be used as a reference by researchers who are using the same infrared thermal camera. It is proven that the machine has high sensitivity in determining the temperature of anterior ocular surface. Methodology used in this study can also be applied to the determination of the accuracy and sensitivity of the dynamic range for other infrared thermal cameras. Inter-subjects OST norm in Chinese young adults aged 17–21 was established.

A new theranostic nanoplatform, comprising of monodisperse zirconium metal-organic frameworks (MOFs) as drug carriers and carboxylatopillar[5]arene-based supramolecular switches as gating entities, is constructed, and controlled drug release triggered by bio-friendly Zn(2+) ions (abundant in synaptic vesicles) and auxiliary thermal stimulus is realized. This on-command drug delivery system exhibits large pore sizes for drug encapsulation, excellent biodegradability and biocompatibility, extremely low cytotoxicity and premature drug release, and superior dual-stimuli responsiveness, opening a new avenue in targeted drug delivery and controlled release of therapeutic agents, especially in the treatment of central nervous system diseases.

Pillarenes and calixarenes showed obvious inhibition of HPV16 L1 pentamer formation via their selective binding to Arg and Lys residues at the monomer interface, which was reversible after the release of cyclic arenes. Pillarenes are more effective than calixarenes in terms of the inhibition efficiency, attributing to the different kinetics and binding affinity.

The purpose of this study was to investigate the extent to which science teachers taught problem solving in elementary science. The survey involved 348 teachers in 36 Singapore elementary schools. The study investigated the science teachers’ views about their use of science instructional techniques in general and the problem-solving teaching approach in particular. It also focused on the difficulties faced by science teachers in implementing the problem-solving teaching approach in the science classroom. It was found that the most emphasised activities were completion of science workbooks, teachers’ explanation of concepts, and hands-on activities. The least emphasised activities were computer-based learning, activities beyond the textbook and workbook, and visits to the ecology garden and other parts of the school. Only about one-third of the teachers often conducted activities pertaining to problem solving. Most of them were more concerned about covering the science syllabus for examinations, the physic...

Acetylcholine (ACh), a neurotransmitter located in cholinergic synapses, can trigger cargo release from mesoporous silica nanoparticles equipped with calixarene- or pillarene-based nanovalves by removing macrocycles from the stalk components. The amount and speed of cargo release can be controlled by varying the concentration of ACh in solution or changing the type of gating macrocycle. Although this proof-of-concept study is far from a real-life application, it provides a possible route to treat diseases related to the central nervous system.

Recent research suggested that cardiac stem cells (CSCs) may have the clinical application for cardiac repair. However, their characteristics and the regulatory mechanisms of their growth and differentiation have not been fully investigated. Vascular endothelial growth factor (VEGF, VEGF-A) is a major regulator of physiological and pathological angiogenesis. But the homing role of VEGF for CSCs is unclear. In this report, CSCs were isolated, purified, and expanded in vitro from rat heart. VEGF, SU5416 (VEGF receptor blocker), and Wortmannin (PI3K/Akt signaling pathway inhibitor) were used for differentiation into vascular endothelial cells (VECs). Real-time qPCR was selected to confirm the role of PI3K/Akt signaling pathway in VECs differentiation from rat CSCs. The result of real-time qPCR demonstrated that PI3K/Akt signaling pathway plays an important role in rat CSCs differentiated into VECs. So, our research provides a theoretical basis and experimental evidence for therapeutic application of rat CSCs to treat cardiac repair.

OBJECTIVE To investigate the expression of gap junction protein Cx43 in the cardiac muscle of spontaneous hypertensive rat and the effects of various antagonists against renin angiotensin aldosterone system (RAAS) on Cx43 expression. METHODS 70 spontaneous hypertensive rats of 8-week age, 200-gram weight were separated into 7 groups, as hypertension, ramipril, telmisartan, eplerenone, ramipril + telmisartan, telmisartan + eplerenone, and ramipril+eplerenone treatment group. Another 10 healthy Wistar rats of the same age and weight were used as control group. All the rats were given intragastric administration at 8 a. m. every morning, and measured arteria caudilis pressure at 0, 4 and 8 week, respectively. 8 weeks later, all the rats were sacrificed, and the hearts were taken to measure the weight of left ventricle and the ratio of left ventricle to body weight. Myocardial fibrosis was observed by HE staining of paraffin embedded sections, and Cx43 expression was examined by RT-PCR and western blot.The arteria caudilis pressure of spontaneous hypertensive rats was significantly higher than that of healthy control Wistar rats (P0.01). The decreased blood pressure was observed in RAAS antagonists treated rats, compared with hypertension group (P0.05). The combined treatment of telmisartan and eplerenone had the best effect of lowering blood pressure. Moreover, the weight of left ventricle, the ratio of left ventricle to body weight, myocardial fibrosis and angiotensin 11 were all prominently decreased in telmisartan and eplerenone combination group (P0.01). The expression of Cx43 in spontaneous hypertensive rats was significantly lower than that of healthy control Wistar rats (P0.01). Increased Cx43 expression was observed in RAAS antagonists treated rats, compared with hypertension group (P0.05).The expression of gap junction protein Cx43 was significantly down-regulated in spontaneous hypertensive rats, while RAAS antagonists increased Cx43 expression. The combination of telmisartan and eplerenone effectively recovered the expression of Cx43 and probably reversed hypertension.

The aim of this study was to investigate whether ZK60, an extruded magnesium alloy, reacts in vivo with an appropriate host response, and to investigate how microarc oxidation treatment influences this in vivo corrosion behavior. Twelve cylinders were machined from as-extruded ZK60, with six cylinders treated with MAO and six left untreated; poly-l-lactic acid pins were used as a control to compare biocompatibility. These cylinders were implanted into the right distal femur of mice along the transepicondylar axis from the medial condyle. Microcomputerized tomography was used to quantitatively analyze corrosion in a nondestructive manner in vivo and the corrosion rate was calculated based on the volume measurements of the residual implants. The physiological response of the rats postimplantation was obtained by clinical observation and blood biochemical analysis. Histological analyses of the soft tissue around the implants were used to assess bone response in relation to the implants. The results obtained clearly indicate that the untreated ZK60 alloy showed high degradation rates in vivo, and that MAO treatment had a significant but unsatisfying effect on protecting the implant from further corrosion. Compared with PLLA, the ZK60 alloy showed good osteoconductivity and osteoinductivity, and, according to biochemical indicators, had good biocompatibility in vivo.

Background Nonviral vectors are attractively used for gene therapy owing to their distinctive advantages. Our previous study has demonstrated that transfer of human IFNγ gene into nasopharyngeal carcinoma (NPC) by using a novel nonviral vector, minicircle (mc), under the control of cytomegalovirus (CMV) promoter was effective to inhibit tumor growth. However, therapies based on CMV promoter cannot express the targeted genes in cancer tissues. Previous studies indicated that the development of human NPC was closely associated with Epstein-Barr virus (EBV) and demonstrated the transcriptional enhancer function of oriP when bound by EBV protein. Therefore, the present study is to explore the targeted gene expression and the anti-tumor effect of a novel tumor-specific gene therapeutic system (mc-oriP-IFNγ) in which the transgene expression was under the transcriptional regulation of oriP promoter. Methodology/Principal Findings Dual-luciferase reporter assay and ELISA were used to assess the expression of luciferase and IFNγ. WST assay was used to assess the cell proliferation. RT-PCR was used to detect the mRNA level of EBNA1. RNAi was used to knockdown the expression of EBNA1. NPC xenograft models in nude mice were used to investigate the targeted antitumor efficacy of mc-oriP-IFNγ. Immunohistochemistry was used to detect the expression and the activity of the IFNγ in tumor sections. Our results demonstrated that mc-oriP vectors mediated comparable gene expression and anti-proliferative effect in the EBV-positive NPC cell line C666-1 compared to mc-CMV vectors. Furthermore, mc-oriP vectors exhibited much lower killing effects on EBV-negative cell lines compared to mc-CMV vectors. The targeted expression of mc-oriP vectors was inhibited by EBNA1-siRNA in C666-1. This selective expression was corroborated in EBV-positive and -negative tumor models. Conclusions/Significance This study demonstrates the feasibility of mc-oriP-IFNγ as a safe and highly effective targeted gene therapeutic system for the treatment of EBV positive NPC.

To confirm the effect of cigarette smoking on β-cell function, and further investigate the mediation effect of abdominal obesity.Participants would include 1440 Chinese smokers who had participated in a community-based chronic disease screening project in Guangzhou and Zhuhai from 2006 to 2007. They were interviewed with structured questionnaire on their socio-demographic status and smoking behaviors. Waist-to-hip ratio (WHR) and fasting serum C-peptide concentration were also measured.After adjustment for the potential confounding factors, when compared with smokers with consumption 1 - 10 cigarettes/day, smokers with consumption of 11 - 20 cigarettes/day (adjusted OR = 1.53, 95%CI: 1.22 - 1.90) or20 cigarettes/day (adjusted OR = 1.92, 95%CI: 1.32 - 2.79) had significant higher risks to get C-peptide concentration larger than its median. Furthermore, 37.54% of the effect of cigarette smoking on C-peptide concentration was partially mediated by abdominal obesity.Cigarette smoking might be a risk factor for β-cell dysfunction and abdominal obesity.

To evaluate the genotoxicity of a magnesium alloy coated with beta-tricalcium phosphate (beta-TCP).Four groups were designed. In the first group, AZ31B magnesium alloy surface was coated with beta-TCP using chemical bath deposition, and in the second group magnesium alloy was tested. The other two groups were negative control (pure titanium) and positive control groups (0.5 mg/L bleomycin). Single cell gel electrophoresis was adopted to investigate genotoxicity of the alloy samples in different groups, and 60 cells from each group were analysed. Tail moment and tail DNA percentage were used as reliable indicators to show DNA damage in lymphocytes induced by every testing sample. Student-Newman-Keuls (SNK) test was used to compare results from 4 groups.There were no significant differences in tail moment and tail DNA percentage between magnesium alloy group [(0.52 +/- 0.12), (6.82 +/- 1.81)%] and magnesium alloy coated with beta-TCP group [(0.51 +/- 0.12), (6.89 +/- 1.93)%, P0.05]. Tail moment and tail DNA percentage in negative group were (0.47 +/- 0.14) and (6.29 +/- 1.64)%, and tail moment and tail DNA percentage in positive group were (5.17 +/- 1.23) and (22.09 +/- 4.51)%.No significant increase was found in DNA damage in lymphocytes induced by magnesium alloy coated with beta-TCP.

To explore effect of erythropoietin on the caspase-3 subfamily in preventing apoptosis of human umbilical vein endothelial cells (HUVECs) induced by oxidized-low density lipoprotein (ox-LDL).Third-sixth passages of HUVECs were used. Two experiments were conducted. In the first experiment, there was a blank control group, ox-LDL control group (100 mg/L, incubated for 48 hours), and low, medium, and high recombinant human erythropoietin (rhEPO) groups (6.25, 25.00, 100.00 kU/L rhEPO incubated for 24 hours+100 mg/L ox-LDL incubated for 48 hours). Another experimental protocol consisted of groups of the cells pretreated with either caspase-3 inhibitor DEVD-CHO, or caspase-8 inhibitor z-IETD-fmk, or caspase-9 inhibitor z-LEHD-fmk of 25 micromol/L for 24 hours, then HUVECs were exposed ox-LDL (100 mg/L) incubated for 48 hours. The activity of caspase-3, caspase-8, or caspase 9 was determined by caspase colorimetric assay. The cell survival rate was assessed with methyl thiazolyl tetrazolium (MTT) method. The positive expression rate of caspase-3 and apoptotic rate were measured by flow cytometer.The activity of caspase-3 was significantly decreased and cell survival rate was increased in the caspase-3 inhibitor group (both P0.05). The activity of caspase-8 was decreased in the caspase-8 inhibitor group (P0.05), but the cell survival rate was not significantly different from that of ox-LDL group (P0.05). The activity of caspase-3 or caspase-9 was lower and cell survival rate was higher in the caspase-9 inhibitor group than that of ox-LDL group (all P0.05). The pretreatment with rhEPO led to decreased activity of caspase-3, caspase-9, positive expression rate of caspase-3 and apoptotic rate in a dose-dependent manner compared with ox-LDL group (all P0.05), but the activity of caspase-8 showed no significant difference from rhEPO pretreatment groups (all P0.05).These results demonstrate that rhEPO can significantly inhibit the activity of caspase-3 or caspase-9 in endothelial cell apoptosis in a dose-dependent manner. Activation of caspase-3 or caspase-9 is involved in ox-LDL-induced HUVECs apoptotic signaling pathway, but caspase-8 is not involved.

A two-dimensional Reynolds equation was established for isothermal compressible gas between the two faces of a dry gas face seal with both spiral grooves and an inner annular groove onto the hard face. The opening force, the leakage rate, the axial film stiffness and the film stiffness to leakage ratio were calculated by finite element method. The comparisons with the sealing performances of a typical gas face seal only with spiral grooves onto its hard face were made. The effects of the face geometric parameters on the static behavior of such a seal were analyzed. The optimization principle for geometric parameters of a dry gas face seals with spiral grooves and an inner annular groove was presented. The recommended geometric parameters of spiral grooves and circular groove presented by optimization can ensure larger axial stiffness while lower leakage rates.Copyright © 2008 by ASME

Between April 1997 and February 2000, total cavopulmonary connection with an extraatrial tunnel was used to treat 9 cases of complicated congenital heart disease: single ventricle (4), double-outlet right ventricle (3), mitral atresia (1), and tricuspid atresia (1). There was no mortality. One patient developed bacterial endocarditis and required reoperation after 52 days to replace the tunnel. At follow-up ranging from 11 months to 3 years, 3 patients were in New York Heart Association functional class I, and 6 were in class II. One patient with single ventricle had refractory supraventricular tachycardia after a modified Fontan operation 4 years earlier, which was cured by the total cavopulmonary connection procedure. The essential factors for a good outcome include appropriate surgical indication, avoidance of aortic crossclamping and cardiac arrest, and unobstructed anastomosis between the superior and inferior venae cavae and the pulmonary artery.

We constructed a novel cancer theranostic hybrid platform, based on mesoporous silica-coated gold nanorods (AuNR@MSN) gated by sulfonatocalix[4]arene (SC[4]A) switches, for bio-friendly near-infrared (NIR) light-triggered cargo release in a remote and stepwise fashion. The advantages of supramolecular switches, mesoporous silicas, and AuNRs were combined in one drug delivery system. Mesoporous silicas coated on AuNRs guarantee a high drug payload and can be easily post-functionalized. Significantly, the plasmonic heating from the NIR light-stimulated AuNR cores can decrease the ring-stalk binding affinity, leading to the dissociation of SC[4]A rings from the stalks, thus opening the nanovalves and releasing the cargos. The NIR light-responsive mechanized AuNR@MSN offers exciting prospects for non-invasive controlled drug delivery, being more effective and safer than other techniques.

Highly selective binding of “solvent” molecules by 1,4-dimethoxypillar[5]arene (DMP[5]A) and their host–guest complexation in solution and the solid state have been investigated by multiple methods. Enthalpy changes and the size-fit effect play an important role in the high selectivity.

A practical and effective trifluoromethanesulfonic acid (TfOH)-catalyzed cyclooligomerization strategy was developed for the synthesis of functionalized pillar[n]arenes and copillar[5]arenes from 1,4-dialkoxybenzenes with paraformaldehyde under mild reaction conditions, and the reaction mechanism of solution-phase catalytic synthesis of pillararenes was investigated by room-temperature X-band ESR spectroscopy, mass spectroscopy, NMR and control experiments, suggesting a free radical process initially and a Friedel-Crafts alkylation process during the consequent coupling and ring-closure stage.