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The prognostic assessment of an ICU patient involves assessing the severity of their condition, interventions, and length of ICU stay. Over the past 30 years, researchers have proposed numerous predictive models and severity assessment scales for ICU patients in specific regions, including APACHE II and SAPS II. However, most existing methods rely heavily on curve fitting which do not account for misclassifications caused by false negatives and positives. Specificity and sensitivity must be provided as an indicator of model performance. The primary aim in this study is to develop a machine-learning model to formulate a prognosis for MICU and SICU patients by using data from the MIMIC-IV for training. The predictive models developed in this study facilitate the prediction of mortality and other outcomes across various treatment regimens.

Convenient and green methods to synthesize highly efficient and stable multi-functional electrode materials are the key and a challenge for the industrial application of new energy conversion devices. Herein, we have developed a general host–guest strategy to construct amorphous hetero-atom doped cobalt phosphates; in the first step, we fast synthesized large-scale 2D Co-based phosphate precursors with different organic amine guest molecules by a hydrothermal method, afterwards, we calcined these precursors at different annealing temperatures, leading to the decomposition of organic guest molecules, and consequently, we obtained amorphous C,N co-doped mesoporous Co-based phosphates during this decomposition process. Moreover, the optimal C4NCPO-450 shows bi-functional activity for the Oxygen Evolution Reaction (OER) and supercapacitor applications. Which has a low overpotential of 292 mV and a Tafel slope of 67.45 mV dec−1 for the OER, and when used as an electrode material for supercapacitors, it reveals a large specific capacitance of 326 F g−1@1 A g−1, accompanied by a stability of 2200 charge and discharge cycles. We suppose that this method can be used to prepare other hetero-atom doped mesoporous electrode materials, which should be promising candidates in the electrochemical energy storage and conversion field.

To realize the detection of pesticide, this study developed a paper-based chip involving a 2D to 3D flow channel and automatic time delay for detecting pesticides. The time delay was controlled by different pullulan concentrations. The 3D channel was fabricated by hot embossing (optimized printing parameters were 28 kg at 80°C, and Advantec No. 1 filter paper was used) and transfer printing the hydrophobic material into the paper. Finally, the limit of the detected concentration of the pesticide was 4 ng/mL, which was achieved using 250 U/mL of acetylcholinesterase (AChE) and 2.5% pullulan solution.

We applied a linear structural equation model to explore the impact of information disclosure, social responsibility, trust, and attitude on consumers' loyalty to housing agents. Participants were 466 consumers and potential consumers of housing agency industry services, who completed a survey assessing the variables of interest. Results showed that information disclosure had a direct and significant impact on trust, and an indirect impact on trust through the mediator of corporate social responsibility (CSR), and that trust had an indirect and significant impact on loyalty through the mediator of attitude. The structural relationships among information disclosure, CSR, trust, and attitude should be acknowledged when discussing consumers' loyalty to housing agents.

Background Theta burst stimulation is a type of pattern-specific repetitive transcranial magnetic stimulation that requires less stimulation time and lower intensity to induce long-lasting effects comparable to those of other repetitive transcranial magnetic stimulation protocols. This pilot study investigated whether continuous theta burst stimulation (cTBS) on the primary motor cortex reduced headache frequency in patients with migraine. Methods Nine patients with migraine were recruited into our study. All patients received 20 cTBS sessions (bursts of 3 50-Hz TMS pulses at 200-ms intervals for 40 seconds), administered every weekday for 4 consecutive weeks. All patients kept headache diaries for 4 weeks before stimulation (baseline; T1), during stimulation (T2), and 4 weeks after stimulation (T3). The primary outcome measures were the changes of total headache and migraine days from baseline (Wilcoxon signed-rank test; T2 and T3 vs. T1). Results The number of total headache days was reduced at T2 and T3 compared with T1 [9.4 ± 6.2 days ( p = 0.024) and 8.7 ± 10.1 days ( p = 0.012) vs. 13.4 ± 10.1 days]. The number of migraine days was also reduced at T2 and T3 compared with T1 [2.9 ± 2.7 days ( p = 0.021) and 1.0 ± 1.6 days ( p = 0.008) vs. 8.6 ± 8.7 days]. Conclusion Our results indicate that cTBS on the primary motor cortex might reduce the number of total headache and migraine days in patients with migraine. However, large-scale randomized controlled trials are necessary to further validate the findings.

Background Glycine receptors (GlyRs) are involved in the development of spinal pain sensitization. The GlyRα3 subunit has recently emerged as a key factor in inflammatory pain pathways in the spinal cord dorsal horn (DH). Our study is to identify the extent of location and cell types expressing different GlyR subunits in spinal cord and dorsal root ganglion (DRGs). To tease out the possible actions of GlyRs on pain transmission, we investigate the effects produced by GlyRs on acute inflammatory pain by behavioral testing using prostaglandin E2 (PGE2) intrathecal injection models. Furthermore, we investigate the changes of GlyR expression in DRGs and spinal cord in rats after the induction of acute inflammatory pain. Results Compared to the vehicle administration, the PGE2 intrathecal injection model produced significantly higher hyperalgesia, which started 3 h after PGE2 injection and lasted more than 5 h. PGE2 intrathecal injection significantly decreased GlyRα1 and GlyRα3 protein expressions in the L5 DH at 1 h and lasted to 5 h, and similar results were observed in the L5 DRG at 5 h. Confocal microscopic images showed the co-existence of punctate gephyrin and GlyRα3 immunoreactivity (IR) throughout the gray matter of the spinal cord, mainly in DH laminae I–III neurons and in ventral horn neurons. It also showed the co-existence of punctate gephyrin and GlyRα3 IR in DRG neurons. Conclusions In this study, PGE2 intrathecal injection significantly decreased protein expression of gephyrin, GlyRα1 and GlyRα3 in spinal cord DH and DRG. The gephyrin and GlyRα3 were localized on neuron cells both in the DH and DRG. Electronic supplementary material The online version of this article (10.1186/s12868-018-0470-8) contains supplementary material, which is available to authorized users.

Recently, cold atmospheric-pressure (CAP) plasma have become a novel and popular tools in biomedical applications. It has been proved that CAP plasma treatment will induce cancer cells death. With different CAP plasma treatment parameters, cells will have different fate including proliferation, apoptosis and cell membrane damage. It has been reported that a low energy plasma will cause cell proliferation while a longer exposures lead to cell death. So, the aim for this study is to induce melanoma cells apoptosis in a short time by CAP plasma-jet. We first evaluate the optimal working condition of CAP plasma-jet including treatment time, voltage, flow-rate and plasma-gas composition. Then we use CAP plasma-jet treat on melanoma cells with different medium volume, cell number and treating times to find a suitable condition for the cell culture. Results demonstrate that with medium 0.6 ml and seeding 104 cells have highest cell viability while treat 180 s and 360 s are significantly decreased. In the migration assay, cells migration ability is both decreased when treat with plasma for 180 s and 360 s. We also do the Hoechst 33258 stain, after treating with CAP plasma melanoma cells are detach from the bottom and have DNA condensation. Finally, we examine ROS expression present/ absent ROS inhibitor sodium pyruvate (SP). Data shows that after CAP plasma treatment ROS expression is induced while cell viability is reduced. But cell viability is recovered by pretreat with ROS inhibitor SP. In conclusion, both cell viability and cell migration ability are inhibited by CAP plasma-jet via ROS mediation in melanoma cells.

Antifouling surfaces that are resistant to protein adsorption and cell adhesion are desirable for many biomedical devices, such as diagnostic devices, biosensors, and implants. In this study, we developed an antifouling hyperbranched polyglycerol (hPG) surface on hydroxyl poly-p-xylylene (PPX-OH). PPX-OH was deposited via chemical vapor deposition (CVD), and an hPG film was then developed via the ring-opening reaction of glycidol. The hPG film greatly reduced the adhesion of L929 cells and platelets as well as protein adsorption. The addition of alkenyl groups in the hPG layer allows the conjugation of biomolecules, such as peptides and biotin, and elicits specific biological interactions. Since the CVD deposition of PPX-OH could be applied to most types of materials, our approach makes it possible to decorate an antifouling hPG film on most types of materials. Our method could be applied to biosensors, diagnostics, and biomedical devices in the future.

We present the development of conductive nanoporous CNT/chitosan membrane for charge-selective transport of charged molecules, carboxylfluorescein (CF), substance P, and tumor necrosis factor-alpha (TNF-α). The membrane was made porous and conductive via gelatin nanoparticle leaching technique and addition of carbon nanotubes, respectively. These nanoporous membranes discriminate the diffusion of positive-charged molecules while inhibiting the passage of negative-charged molecules as positive potential was applied. The permeation selectivity of these membranes is reversed by converting the polarity of applied potential into negative. Based on this principle, charged molecules (carboxylfluorescein, substance P, and TNF-α) are successfully filtered through these membranes. This system shows 30 times more selective for CF than substance P as positive potential was applied, while 2.5 times more selective for substance P than CF as negative potential was applied.

A new anodic material of ternary Pb-0.8%Ag-(0–5.0%)Bi alloy for zinc electrowinning was obtained by doping Bi. The anodic oxygen evolution potential, corrosion rate, surface products after polarization, and microstructures before and after polarization were studied and compared with those of Pb-0.8%Ag anode used in industry. The results show the anodic overpotential decreases with the increase of Bi content in the alloys. When the content of Bi is 1.0% (mass fraction), the anodic overpotential is 40–50 mV lower than that of Pb-0.8%Ag anode. While the corrosion rate decreases and then increases with the increase of Bi content. The Pb-0.8%Ag-0.1%Bi anode has the lowest corrosion rate (0.090 6 mg/(h·cm2). Doping Bi influences the structure of the anodic layer, but does not change the phase. The Pb-0.8%Ag-1.0%Bi anode layer is of a more fine-grained structure compared with Pb-0.8%Ag anode.

A new type of lead-based porous anode in zinc electrowinning was prepared by negative pressure infiltration. The anodic polarization potential and corrosion rate were studied and compared with those of traditional flat anodes (Pb-0.8%Ag) used in industry. The anode corrosion rate was determined by anode actual current density and microstructure. The results show that the anodic oxygen evolution potential decreases first and then increases with the decrease of pore diameter. The anodic potential decreases to the lowest value of 1.729 V at the pore diameter of 1.25–1.60 mm. The porous anode can decrease its actual current density and thus decrease the anodic corrosion rate. When the pore diameter is 1.60–2.00 mm, the anodic relative corrosion rate reaches the lowest value of 52.1%.

Previously, we have demonstrated the induction of Src in lipopolysaccharide (LPS)-stimulated macrophages. In this study, we observed that pharmacological blockade or knockout of inducible nitric-oxide synthase (iNOS) reduced LPS-mediated Src induction and macrophage migration. Either SNAP (a NO donor) or 8-Br-cGMP (a cGMP analogue) could rescue these defects in iNOS-null macrophages, which indicated the participation of NO/cGMP in LPS-elicited Src expression and mobilization. In addition, Src family kinase (SFK)-specific inhibitor, PP2, inhibited SNAP- and 8-Br-cGMP-evoked motility implicating the involvement of SFKs downstream of NO/cGMP. Analysis of the expression of SFKs indicated LPS dramatically induced Src, which could be attributable to the increased level of the src transcript. Attenuation of Src by src-specific siRNA reduced LPS- and SNAP-evoked mobilization in Raw264.7 macrophages, and reintroduction of avian Src could rescue their motility. Furthermore, LPS-mediated Src induction led to increased FAK Pi-Tyr-397 and Pi-Tyr-861, which was also iNOS-dependent. With these findings, we concluded that iNOS was important for LPS-mediated macrophage locomotion and Src was a critical player in this process.

A novel silicon strip detector has been developed that has the necessary properties to provide two-dimensional position sensitivity with a moderate number of readouts and single-sided detector fabrication process. The concept is based on segmented pixel electrodes arranged in a projective X-Y readouts, it combines the 2-D position resolution of pixel electrode geometry with the simplicity of the projective readout of a double-sided strip detector. And also with proper segmentation of strip electrodes, the multi-hits induced ghost image problem can be resolved.

The purpose of this study was to develop kinds of multi-walled carbon nanotubes (MWCNT)-based materials, which could replace current autografts for neuron regeneration. The alternative MWCNT films was developed by encapsulated chitosan. To evaluate the characteristics of MWCNT films after modification, the measurements of electrical conductivity, contact angle and the degree of degradation were carried out. Two kinds of chitosan film preparation were designed, one was the dish film and the other was microscope slide film. The microscope slide film was exterior, however, the dish film was wrinkling. Comparing the thickness by micrometer caliper, the thickness of the dish film was 0.1950 to 0.0425 mm, and the microscope slide film was 0.0584 to 0.0109 mm. This result indicated the microscope slide film was more suitable for the following experiment because of less error value. The contact angle of the chitosan film was measured between 60~90 deg, it indicated the film was more hydrophobic. In order to achieve better biocompatibility, adding MWCNT significantly increased hydrophilicity of chitosan film.

One of the reason caused the production of scar is the excessive sediment or the overtime precipitation during the wounds healing. So far amount all the medical supplies, hydrocolloid dressings which used to repair the burn wounds and the normal trauma are bass on promotion of wound healing. Nevertheless there are no medical supplies combine hydrocolloid dressings with anti-pigmentation drugs; therefor our research has focused on preparing gelatin nanoparticle. First, prepared different size of particles by controlling the parameters. Second, loaded various concentrations of ascorbic acid into particles, analyzed the drug entrapment efficiency and the rate of drug release. Last, co-culture nanoparticle with fibroblast, research the effect of nanoparticle on the fibroblast, in order to prepare a successful anti pigmentation gelatin nanoparticle. Under distinct condition, particle size 150nm ~ 300nm of gelatin nanoparticle could be prepared, furthermore the effective concentration of ascorbic acid 0.3%~10% is successfully completed and the drug-loaded nanoparticles are able to extend the life-span of the fibroblast.

This study attempted to enhance the efficacy of peripheral nerve regeneration using our previously developed gelatin-tricalcium phosphate (GTG) conduits by incorporating them with nerve growth factors and cultured Schwann cells. The nerve growth factors were covalently immobilized onto the GTG conduits (GEN) using carbodiimide. Schwann cells were harvested from neonatal Lewis rats, cultured for seven days and injected into the GEN conduits. The experiment was performed in three groups: GTG conduits, GEN conduits and GEN conduits with Schwann cells injected (GEN+Sc). The effects of different conduits (GTG, GEN and GEN with Schwann cells) on the peripheral nerve regeneration were evaluated in rat sciatic nerve repair model. 24 weeks after implantation of conduits, degradation of the conduits in all groups was illustrated by the fragmentation of the conduits. All conduits were well tolerated by the host tissue. Under microscopic evaluations, regenerated nerve tissue with myelinated and unmyelinated axons presented in all groups. Histomorphometrically, the total nerve area of GEN+Sc group was significantly higher than GTG group. Conversely, the autotomy score evaluated 12 weeks after nerve repair showed better results for GTG group. Besides, GEN+Sc group had the highest average recovery index of compound muscle action potential, but the difference among each group did not reach statistical significance. Although the electrophysiological recovery of nerve was not significantly improved with GEN+Sc conduit, nerve repair using tissue engineered conduits still provided better histological results. However, it should be noticed that autotomy may be the price paid for enhanced peripheral nerve.

The gelatin-tricalcium phosphate membranes were cross-linking with low concentration glutaraldehyde solution (GTG). This material has good mechanical property, biocompatibility, and is feasible for surgical manipulation. For axonal regeneration, nerve growth factors (NGF) were immobilized onto the composite (GTG) with carbodiimide. The purpose of this study was to evaluate the release characteristics and bioactivity of NGF after covalent immobilization onto the GTG membranes (GEN). NGF immobilized onto and released from the composite was quantified using ELISA method. PC 12 cells were cultured on the GTG and GEN composites. Cell survival, cytotoxicity, and cellular activity were evaluated by total protein content, LDH activity, and MTT assay respectively. Neurite outgrowth assay was used to evaluate the biological activity of NGF released from GEN composite. From ELISA measurement, the releasing curve for NGF showing two distinctive parts with different slopes indicated that NGF were released from the composite in diffusion-controlled mechanism and degradation-controlled mechanism respectively. While culturing with PC 12 cells, LDH leakage results implied that whether GTG composite cross-linked with NGF or not showed little cytotoxicity. The total protein content and cellular activity of PC 12 cells were lower on GTG and GEN membranes than control group. However, 56%±3.98 of PC 12 cells showed significant neurite outgrowth on GEN membranes which was statistically higher than GTG without NGF immobilization. In addition, sustained release of bioactive NGF for two months had been demonstrated by neurite outgrowth assay. From these experiments, it can be concluded that the technique used in the present study is capable of immobilizing NGF onto GTG membranes covalently and remaining the bioactivity of NGF. Therefore, GEN composite can be materials for sustained release of bioactive NGF and a candidate for future therapeutic application in nerve repair.

The thermal and degradable properties of carbodiimide (EDC) or glutaraldehyde (GTA) cross-linked gelatin membranes have been investigated in order to evaluate the effects of different concentrations of two kinds of cross-linking reagent on the stability of membranes. In the thermogram recorded from a gelatin membrane cross-linked with EDC solution, the endothermic peak of 0.8% EDC cross-linking gelatin was centered at about 61°C that was higher than other samples treated with EDC solutions. Denaturation temperature (Td) of gelatin samples increased on increasing EDC concentration (0.2% to 0.8%), in agreement with the simultaneous increased of the extent of cross-linking. But increasing GTA concentration from 0.05% to 0.6%, the Td values of gelatin samples were decreased from 66.2°C to 56.3°C . In addition, two endothermic peaks were observed in 0.4% and 0.6% GTA cross-linking groups because of the GTA concentration was too high to complete cross-linking reaction. Therefore, partial of gelatin membrane was cross-linked completely but others were not. In the thermogravimetric analysis, the proportion of cracking endothermic peak of 0.6% GTA cross-linking gelatin (g15G0.6) was higher than the peak of 0.6% EDC cross-linking gelatin (g15C0.6). Therefore, g15G0.6 cracked to smaller molecules has to absorb more calorific capacity than g15C0.6. The increase in the strength of covalent binding on increasing the proportion of endothermic peak was evident. The results of degradable rate were in agreement with the lower concentration of cross-linked reagent the faster degraded rate of gelatin membrane. The MTT assay showed that 15% gelatin cross-linked by 0.8% EDC has the least cytotoxicity, and cell activity of this group was similar to control group (blank dish). As the concentration of GTA in gelatin membranes was down to 0.05% or 0.1% the cell viability was returned to approach the value of control group.

The purpose of this study was to investigate if PPARγplays a role in the melanogenesis. B16/F10 cells were divided into five groups: control, melanin stimulating hormone (α-MSH),α-MSH+retinol,α-MSH+GW9662 (PPARγantagonist), and GW9662. Cells in the control group were cultured in the Dulbecco’s modified Eagle’s medium (DMEM) for 48 hrs. To initiate the melanogenesis, cells in allα-MSH groups were cultured in medium containingα-MSH (10 nM) for 48 hrs. Cells were treated simultaneously with retinol (5 μM) in theα-MSH+retinol group. Instead of retinol, GW9662 (10 μM) was cocultured in theα-MSH+GW9662 group. Cells in the final group were cultured in the DMEM with GW9662. All the analyses were carried out 48 hours after treatments. Theα-MSH was able to increase cell number, melanin production, and the activity of tyrosinase, the limiting enzyme in melanogenesis. Theseα-MSH-induced changes were prevented either by retinol or by GW9662. Further analyses of the activities of antioxidant enzymes including glutathione, catalase, and the superoxide dismutase (SOD) showed thatα-MSH treatment raised the activity of SOD which was dependent on PPARγlevel. According to our results, theα-MSH-induced melanogenesis was PPARγdependent, which also modulated the expression of SOD.

In this article, a nanoporous chitosan polymer membrane was successfully produced and applied as microdialysis membrane forin vitrosampling of biomolecules. With the use of nanoparticle leaching technique, porogenic gelatin nanoparticles formed nanopores in the chitosan-based membrane to create a secure implantable nanoporous membrane for biomolecule sampling. The gelatin nanoparticles size was in the range of 45 to 70 nm, and the pore size of the chitosan membrane was around 40 to 100 nm. The porosity of membrane was found to be dependent on the mixing ratio of chitosan solution and gelatin nanoparticles solution. The results of diffusion study showed that we can alter the mixing ratio of porogen to achieve size-selective molecular diffusion, which means that the porosity and cut-off size of porous membrane can be controlled. The recoveries of the probe fabricated from the chitosan-based membrane were examined for four different model compounds of different molecular weights: 2-NBDG, substance P, TNF-α, and FITC-BSA. The microdialysis probes showed linear responses and substantial recovery to various concentrations of biomolecules. These results indicated that the microdialysis probe constructed by chitosan nanoporous membrane could sample and monitor the biomoleculesin vitroand has the potential for the applicationin vivo.

Fresh common (Agaricus bisporus) and high-temperature mushrooms (A. bitorquis) were irradiated with ultraviolet-C (UV-C) for 0, 0.5, 1, and 2 h at 12 °C. Fresh common, shiitake (Lentinula edodes), and straw mushrooms (Volvariella volvacea) were irradiated with UV-B for 0, 0.5, 1, and 2 h at 12 °C. After UV-C irradiation for 2 h, vitamin D2 contents in common and high-temperature mushrooms increased from 2.20 and 4.01 μg/g of dry weight to 7.30 and 5.32 μg/g, respectively. After UV-B irradiation for 2 h, the vitamin D2 content in common mushrooms reached 12.48 μg/g. UV-B irradiation resulted in higher vitamin D2 conversion for common mushrooms. After UV-B irradiation for 2 h, vitamin D2 contents in shiitake and straw mushrooms increased from 2.16 and 3.86 μg/g to 6.58 and 7.58 μg/g, respectively. The increase rates in shiitake and straw mushrooms were not as high as in common mushrooms. Keywords: Mushrooms; Agaricus bisporus; Agaricus bitorquis; Lentinula edodes; Volvariella volvacea; ultraviolet-B; ultrav...

A novel silicon p-i-n diodes for detecting backscattering electrons in SEM was proposed and fabricated. The multi-annular configuration enables to provide better surface topography contrast of BSE image compared with traditional quadratic configuration. In this study, the multi-annular backscattered electron detector (BSED) can provide surface topography contrast of 82.11 nA/μm, which is 105% increase as compared with commercial BSED. Besides, the multi-annular detector has lower threshold detective energy of 1.28 keV and wide detective dynamic range (up to 30 keV). It is demonstrated that the multi-annular BSE detector is well suited for imaging in SEM system.

According to the multiple alignment of various dihydrolipoamide dehydrogenases (E3s) sequences, three human mutant E3s of the conserved residues in the center domain, N286D, N286Q, and D320N were created, over-expressed and purified. We characterized these mutants to investigate the reaction mechanism of human dihydrolipoamide dehydrogenases. The specific activities of N286D, N286Q, and D320N are 30.84%, 24.57% and 48.60% to that of the wild-type E3 respectively. The FAD content analysis indicated that these mutant E3s about 96.0%, 99.4% and 82.7% of FAD content compared to that of wild-type E3 respectively. The molecular weight analysis showed that these three mutant proteins form the dimer. Kinetic's data demonstrated that the K(cat) of both forward and reverse reactions of these mutant proteins were decreased. These results suggest that N286 and D320 play a role in the catalytic function of the E3.

In order to modulate the mechanical properties of gelatin, we previously developed a biodegradable composite composed by tricalcium phosphate and glutaraldehyde crosslinking gelatin (GTG) feasible for surgical manipulation. In this study, we evaluated the in vivo applications of GTG conduit for peripheral nerve repair. The effect of sciatic nerve reconstruction was compared between resorbable permeable GTG conduits and durable impermeable silicone tubes. Traditional methods of assessing nerve recovery following peripheral nerve repair including histomorphometric and electrophysiologic features were conducted in our study. In addition, autotomy score and sciatic function index (SFI) in walking tract analysis were used as additional parameters for assessing the return of nerve function. Twenty-four weeks after sciatic nerve repair, the GTG conduits were harvested. Microscopically, regeneration of nerves was observed in the cross-section at the mid portion of all implanted GTG conduits. The cross-sectional area of regenerated nerve of the GTG group was significant larger than that of the silicone group. In the compound muscle action potentials (CMAP), the mean recovery index of CMAP amplitude was 0.24 ± 0.02 for the silicone group, 0.41 ± 0.07 for the GTG group. The mean SFI increased with time in the GTG group during the evaluation period until 24 weeks. Walking tract analysis showed a higher SFI score in the GTG group at both 12 and 24 weeks. The difference reached a significant level at 24 weeks. Thus, the histomorphometric, electrophysiologic, and functional assessments demonstrate that GTG can be a candidate for peripheral nerve repair. © 2005 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2006

We previously developed a biodegradable composite with potentially good biocompatibility composed by tricalcium phosphate and gluataraldehyde cross-linking gelatin (GTG) with good mechanical property feasible for surgical manipulation. The purpose of this study was to evaluate the feasibility of immobilizing nerve growth factor (NGF) onto the composite (GTG) with carbodiimide (GEN composite). Cultured Schwann cells were seeded onto the GTG and GEN composites. For comparison, GTG membrane soaked in NGF solution without carbodiimide (GN composite) as cross-linking agent was also used to culture Schwann cells. Cell morphology was observed by a scanning electron microscope. Cell survival, cytotoxicity and cellular metabolism on the NGF-grafted GTG membrane were assessed quantitatively in terms of cell protein content, leakage of cytosolic lactate dehydrogenase (LDH) activity and by the well-established MTT assay, respectively. The result of LDH study did not show significant difference among GTG, NGF-modified GTG and control group. This indicated that GTG composite, whether cross-linking with NGF or not, has little cytotoxic effect. Comparing the protein content and MTT assay among GEN, GN composite and control group, the data confirmed more attachment of Schwann cells on GEN composite. Although GTG cross-linking with NGF did not promote Schwann cell proliferation, the techniques we used in this study provided a method to fabricate a novel biomaterial incorporation of Schwann cells and covalently immobilized NGF.

We have performed genetic screening on the skeletal muscle chloride channel gene (CLCN1) in Taiwanese population. A total of four patients with myotonia congenita (MC) together with 106 normal individuals were examined. All 23 exons of the CLCN1 gene were analysed by direct sequencing of PCR products to detect the nucleotide changes. Five mutations and three polymorphisms were identified in this study. Among these, three missense mutations (S471F, P575S, D644G) and one polymorphism (T736I) are novel and could be unique to the Taiwanese. In addition, a previously documented recessive G482R mutation was identified in a heterozygous patient and his nonsymptomatic father, indicating that this mutation might indeed function recessively or dominantly with incomplete penetrance. In conclusion, this is the first report of MC in Taiwan with proven CLCN1 gene mutations and showing high molecular heterogeneity in Taiwanese MC patients.

By integrating a planar waveguide and scattering phenomenon generated by electrostatically actuating a transparent polymer thin film, a display chip capable of being cleared and re-displayed was developed using micro fabrication technology. In the design of the display chip, a freestanding transparent PDMS/ITO conductive composite membrane is sustained by SU-8 spacers above a glass substrate which acts as a light waveguide, and electrostatic force is used to carry out the deflection of the PDMS/ITO composite membrane. When electrostatic force is applied, the PDMS/ITO composite membrane deflects and comes into contact with the glass substrate, causing light to leak out of the waveguide, due to which the critical angle of the total internal reflection of the glass waveguide changes. On switching off the electric potential, the PDMS/ITO membrane returns to its initial state so that light cannot leak out, and a dark spot is formed. Thus, micro-optical switching can be performed by this mechanism. In this display chip an aluminum layer was applied as an adhesive layer between the SU-8 spacers and the glass waveguide, which prevented the leakage of light. The experimental results show that a waveguide with an electrode length of 250 µm (sub-pixel length), a micro-post height of 23 µm and a PDMS film thickness of 8 µm require an actuator voltage of 149 V to operate in a pull-in mode. The optical testing results successfully demonstrate the functionality and the ability to light up multiple pixels of an electrostatic actuating display (EAD) device. Therefore, the EAD device has great potential for the development of low cost dual displays.