Tuning the emission properties of a fluorescent polymer using a polymer microarray approach - identification of an optothermo responsive polymer

Fluorescent polymer microarrays were prepared using inkjet printing and screened. The fluorescence intensity was found to be tunable by temperature change when the dye was immobilized in identified thermo-responsive polymer beads.</p

Differential Responses of Cultured MC3T3-E1 Cells to Dynamic and Static Stimulated Effect of Microgravity in Cell Morphology, Cytoskeleton Structure and Ca²⁺ Signaling

Random positioning machine (RPM) and diamagnetic levitation are two essential ground-based methods used to stimulate the effect of microgravity in space life science research. However, the force fields generated by these two methods are fundamentally different, as RPM generates a dynamic force field acting on the surface in contact with supporting substrate, whereas diamagnetic levitation generates a static force field acting on the whole body volume of the object (e.g. cell). Surprisingly, it is hardly studied whether these two fundamentally different force fields would cause different responses in mammalian cells. Thus we exposed cultured MC3T3-E1 osteoblasts to either dynamically stimulated effect of microgravity (d-µg) with RPM or statically stimulated effect of microgravity (s-µg) with diamagnetic levitation, respectively, for 3 h. Subsequently, the cells were examined for changes in cell morphology, cytoskeleton (CSK) structure and Ca2+ signaling. The results show that compared to the condition of normal gravity (1g), both d-µg and s-µg resulted in decrease of cell area and disruption of the microfilaments and microtubules in MC3T3-E1 cells, but cells under d-µg were more smooth and round while those under s-µg exhibited more protrusions. The decrease of cell area and disruption of microfilaments and microtubules induced by d-µg but not s-µg were rescued by inhibition of the stretch-activated channel by gadolinium chloride (Gd). Inhibition of calmodulin (CaM) by inhibitor, W-7, promoted the effects of s-µg on cell area and CSK filaments, but inhibition of calmodulin-dependent protein kinase (CaMK) by inhibitor, KN-93, weakened d-µg-induced effects on cell area and cytoskeleton. In addition, both d-µg and s-µg decreased the CaM expression and CaMKⅡ activity in MC3T3-E1 cells. Furthermore, s-µg resulted in decrease of the intracellular free Ca2+ concentration ([Ca2+]i) in MC3T3-E1 cells, which was reversed by disrupting microfilaments with cytochalasin B (CytB). Instead, d-µg induced increase of [Ca2+]i, which was inhibited by Gd. Taken together these data suggest that dynamic and static stimulated microgravity cause different responses in MC3T3-E1 cells. The dynamic force field acts on stretch-activated channels to induce microfilaments disruption and Ca2+ influx in MC3T3-E1 cells whereas the static force field directly induces microfilament disruption, which in turn decreases the [Ca2+]i in MC3T3-E1 cells. Such findings may have important implications to better understanding microgravity related cellular events and their applications

Sanguinarine Decreases Cell Stiffness and Traction Force and Inhibits the Reactivity of Airway Smooth Muscle Cells in Culture

Airway hyperresponsiveness (AHR) is the cardinal character of asthma, which involves the biomechanical properties such as cell stiffness and traction force of airway smooth muscle cells (ASMCs). Therefore, these biomechanical properties comprise logical targets of therapy. β2-adrenergic agonist is currently the mainstream drug to target ASMCs in clinical practice for treating asthma. However, this drug is known for side effects such as desensitization and non-responsiveness in some patients. Therefore, it is desirable to search for new drug agents to be alternative of β2-adrenergic agonist. In this context, sanguinarine, a natural product derived from plants such as bloodroots, that has been reported to relax gut smooth muscle emerges as a potential candidate. So far, it is unknown whether sanguinarine can regulate the biomechanical properties of ASMCs and reactivity of ASMCs to irritants. Thus, we tested the hypothesis that sanguinarine reduce the contractile potentials of ASMCs in culture. To do so, the primary cultured rat ASMCs were first treated with different concentration of sanguinarine. Then, cell stiffness, traction force, fiber distribution, and calcium signaling of the ASMCs were evaluated by optical magnetic twisting cytometry, Fourier transform traction microscopy, atomic force microscopy, and Fluo-4/AM based fluorescence confocal scanning microscopy, respectively. The results indicated that sanguinarine (0.05 and 0.5 μmol/L) significantly decreased cell stiffness and traction force, inhibited reactivity of ASMCs to histamine, and disrupted the fiber structures in ASMCs in dose-dependent manner. These findings establish that sanguinarine can indeed change the biomechanical properties of ASMCs and may be used to treat AHR in asthma

Biodegradable pH-responsive hydrogels for controlled dual-drug release

pH-Responsive biodegradable hydrogels based on NIPAM/AA and a PLLA/PEG macro-crosslinker demonstrated pH mediated differential release of doxorubicin and tetracycline.</p

Antiproliferation and cell apoptosis inducing bioactivities of constituents from Dysosma versipellis in PC3 and Bcap-37 cell lines

<p>Abstract</p> <p>Background</p> <p>Recently, interest in phytochemicals from traditional Chinese medicinal herbs with the capability to inhibit cancer cells growth and proliferation has been growing rapidly due to their nontoxic nature. <it>Dysosma versipellis </it>as Bereridaceae plants is an endemic species in China, which has been proved to be an important Chinese herbal medicine because of its biological activity. However, systematic and comprehensive studies on the phytochemicals from <it>Dysosma versipellis </it>and their bioactivity are limited.</p> <p>Results</p> <p>Fifteen compounds were isolated and characterized from the roots of <it>Dysosma versipellis</it>, among which six compounds were isolated from this plant for the first time. The inhibitory activities of these compounds were investigated on tumor cells PC3, Bcap-37 and BGC-823 <it>in vitro </it>by MTT method, and the results showed that podophyllotoxone (PTO) and 4'-demethyldeoxypodophyllotoxin (DDPT) had potent inhibitory activities against the growth of human carcinoma cell lines. Subsequent fluorescence staining and flow cytometry analysis indicated that these two compounds could induce apoptosis in PC3 and Bcap-37 cells, and the apoptosis ratios reached the peak (12.0% and 14.1%) after 72 h of treatment at 20 <it>μ</it>M, respectively.</p> <p>Conclusions</p> <p>This study suggests that most of the compounds from the roots of <it>D. versipellis </it>could inhibit the growth of human carcinoma cells. In addition, PTO and DDPT could induce apoptosis of tumor cells.</p

Development of a Small Portable Device for Measuring Respiratory System Resistance Based on Forced Oscillation Technique

Spirometry and forced oscillation technique (FOT) are two different methods that are currently used for lung function test. However, the former requires patient’s effort to cooperate, thus is often unreliable for certain patients such as the young children and the latter is always related to bulky and expensive machines. In order to overcome the limitations of current device, we developed a portable prototype of FOT device for measuring respiratory resistance. The device consisted of a small advanced voice coil actuator to generate sinusoidal oscillatory airflow with amplitude of 2.5 cmH2O and frequency of 5 Hz, which was then superimposed onto the normal breathing airflow of the patient via a mouth piece. The pressure and flow signals of the respiratory airflow after absorption and refraction by the airways and the lung tissues were detected and acquired using NI USB-6211 data acquisition card and synchronous sampling pressure and flow sensors. After the upper computer received the digital signals that the capture card converted, the signals were processed and analyzed in real-time by the proprietary LabVIEW-based software. The analysis included digital signal filtering and impedance calculation in frequency domain, resulting in respiratory system resistance (Rrs) and reactance (Xrs). The results of present experiments on healthy volunteers demonstrated that the device could measure the respiratory system resistance with good reliability and accuracy. Importantly, due to both the hardware and software design the weight and volume of this device was reduced down to 3.5kg and 2500 cm3, respectively, proving the prototype to be worth of further developing into an inexpensive and portable tool for testing or monitoring lung function at rural community clinics or homes

Prevalence and patterns of tobacco smoking among Chinese adult men and women: findings of the 2010 national smoking survey

Background: China consumes about forty percent of the world’s cigarettes, predominantly by men, following a large increase in recent decades. We assess sex-specific prevalence and changing patterns of smoking in Chinese adults in the current decade. Methods: A nationally representative survey of smoking was conducted in 2010 among 100,000 Chinese adults aged ≥18 years, using multi-stage stratified cluster sampling method. Information on smoking frequency, type, amount, age started, and quitting was collected. Sex-specific standardised prevalence and means were analysed and compared with estimates in 1996 national survey. Results: In Chinese men aged ≥18, 62.4% were ever smokers in 2010, including 54.0% current and 8.4% ex-smokers. The smoking prevalence was higher in rural than in urban men (63.9% vs 58.4%). In younger men the age started smoking was earlier and exclusive cigarette use was much higher. Among current smokers, only 17.3% intended to quit. Compared with similar survey in 1996 among adults aged 30-69, more smokers had quit in 2010 than in 1996 (11.0% vs 4.2%), but the number of cigarettes smoked per current smoker was higher (17.9 vs 15.2). In Chinese women, only 3.4% ever smoked and there has been a large intergenerational decrease in smoking uptake rates. In 2010, there were 318 million current smokers in China, consuming estimated 1740 billion cigarettes. Conclusion: The prevalence of smoking remained extremely high in men, but low and falling in Chinese women. Tobacco smoking remains an important public health issue in China, and stronger and more efficient tobacco control is urgently needed

Yttrium-90 selective internal radiation therapy on liver cancer: the past, the present, and the future

Yttrium-90 selective internal radiation therapy (90Y-SIRT) is a treatment technique that delivers radioactive microspheres precisely to the arterial vascular bed of neoplasms, utilizing beta radiation to administer a high local dose of radiation to the neoplasm tissues. This technology has demonstrated significant efficacy in patients with unresectable pirmary liver cancers and liver metastases. This article systematically reviews the development history and clinical application status of 90Y-SIRT in the treatment of liver cancer, and looks forward to future development directions

Global, regional, and national incidence and mortality for HIV, tuberculosis, and malaria during 1990–2013: a systematic analysis for the Global Burden of Disease Study 2013

BACKGROUND: The Millennium Declaration in 2000 brought special global attention to HIV, tuberculosis, and malaria through the formulation of Millennium Development Goal (MDG) 6. The Global Burden of Disease 2013 study provides a consistent and comprehensive approach to disease estimation for between 1990 and 2013, and an opportunity to assess whether accelerated progress has occured since the Millennium Declaration. METHODS: To estimate incidence and mortality for HIV, we used the UNAIDS Spectrum model appropriately modified based on a systematic review of available studies of mortality with and without antiretroviral therapy (ART). For concentrated epidemics, we calibrated Spectrum models to fit vital registration data corrected for misclassification of HIV deaths. In generalised epidemics, we minimised a loss function to select epidemic curves most consistent with prevalence data and demographic data for all-cause mortality. We analysed counterfactual scenarios for HIV to assess years of life saved through prevention of mother-to-child transmission (PMTCT) and ART. For tuberculosis, we analysed vital registration and verbal autopsy data to estimate mortality using cause of death ensemble modelling. We analysed data for corrected case-notifications, expert opinions on the case-detection rate, prevalence surveys, and estimated cause-specific mortality using Bayesian meta-regression to generate consistent trends in all parameters. We analysed malaria mortality and incidence using an updated cause of death database, a systematic analysis of verbal autopsy validation studies for malaria, and recent studies (2010-13) of incidence, drug resistance, and coverage of insecticide-treated bednets. FINDINGS: Globally in 2013, there were 1·8 million new HIV infections (95% uncertainty interval 1·7 million to 2·1 million), 29·2 million prevalent HIV cases (28·1 to 31·7), and 1·3 million HIV deaths (1·3 to 1·5). At the peak of the epidemic in 2005, HIV caused 1·7 million deaths (1·6 million to 1·9 million). Concentrated epidemics in Latin America and eastern Europe are substantially smaller than previously estimated. Through interventions including PMTCT and ART, 19·1 million life-years (16·6 million to 21·5 million) have been saved, 70·3% (65·4 to 76·1) in developing countries. From 2000 to 2011, the ratio of development assistance for health for HIV to years of life saved through intervention was US$4498 in developing countries. Including in HIV-positive individuals, all-form tuberculosis incidence was 7·5 million (7·4 million to 7·7 million), prevalence was 11·9 million (11·6 million to 12·2 million), and number of deaths was 1·4 million (1·3 million to 1·5 million) in 2013. In the same year and in only individuals who were HIV-negative, all-form tuberculosis incidence was 7·1 million (6·9 million to 7·3 million), prevalence was 11·2 million (10·8 million to 11·6 million), and number of deaths was 1·3 million (1·2 million to 1·4 million). Annualised rates of change (ARC) for incidence, prevalence, and death became negative after 2000. Tuberculosis in HIV-negative individuals disproportionately occurs in men and boys (versus women and girls); 64·0% of cases (63·6 to 64·3) and 64·7% of deaths (60·8 to 70·3). Globally, malaria cases and deaths grew rapidly from 1990 reaching a peak of 232 million cases (143 million to 387 million) in 2003 and 1·2 million deaths (1·1 million to 1·4 million) in 2004. Since 2004, child deaths from malaria in sub-Saharan Africa have decreased by 31·5% (15·7 to 44·1). Outside of Africa, malaria mortality has been steadily decreasing since 1990. INTERPRETATION: Our estimates of the number of people living with HIV are 18·7% smaller than UNAIDS's estimates in 2012. The number of people living with malaria is larger than estimated by WHO. The number of people living with HIV, tuberculosis, or malaria have all decreased since 2000. At the global level, upward trends for malaria and HIV deaths have been reversed and declines in tuberculosis deaths have accelerated. 101 countries (74 of which are developing) still have increasing HIV incidence. Substantial progress since the Millennium Declaration is an encouraging sign of the effect of global action. FUNDING: Bill & Melinda Gates Foundation