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Chia-Ying Lin

Publications and source records attributed to Chia-Ying Lin.

5 recordsLinked to original sources
PubMed2007

Pravastatin induces thrombomodulin expression in TNFalpha-treated human aortic endothelial cells by inhibiting Rac1 and Cdc42 translocation and activity.

Expression of functionally active thrombomodulin (TM) on the luminal surface of endothelial cells is critical for vascular thromboresistance. The 3-hydroxyl-3-methyl coenzyme A reductase inhibitor, pravastatin, can protect the vasculature in a manner that is independent of its lipid-lowering activity. We examined the effect of pravastatin on TM expression by human aortic endothelial cells (HAECs) with subsequent tumor necrosis factor alpha (TNFalpha) stimulation and investigated the signaling pathways involved. TNFalpha treatment attenuated TM expression in HAECs in a time-dependent manner. Pravastatin upregulated TM levels in TNFalpha-treated HAECs. Specific inhibition of geranylgeranyltransferase-I or the Rho family by GGTI-286 or TcdB, respectively, enhanced TM expression in TNFalpha-treated HAECs, whereas MAP kinase inhibitors, inactivation of Rho by Clostridium botulinum C3 exoenzyme, or the Rho kinase inhibitor, Y-27632, had no effect. In TNFalpha-treated HAECs, pravastatin inhibited Rac1 and Cdc42 activation and their translocation to the cell membrane. Blocking the transcriptional activation of NF-kappaB prevented the TNFalpha-induced downregulation of TM. The pravastatin-induced increase in TM expression in TNFalpha-treated HAECs was mediated through inhibition of NF-kappaB activation. Pravastatin regulates TM expression by inhibiting the activation of the Rho family proteins, Rac1 and Cdc42, and the transcription factor, NF-kappaB. The increase in endothelial TM activity in response to pravastatin constitutes a novel pleiotropic (nonlipid-related) effect of this commonly used compound and may be of clinical significance in disorders in which deficient endothelial TM plays a pathophysiological role.

Amides↗
PubMed2004

Interbody fusion cage design using integrated global layout and local microstructure topology optimization.

STUDY DESIGN: An approach combining global layout and local microstructure topology optimization was used to create a new interbody fusion cage design that concurrently enhanced stability, biofactor delivery, and mechanical tissue stimulation for improved arthrodesis. OBJECTIVE: To develop a new interbody fusion cage design by topology optimization with porous internal architecture. To compare the performance of this new design to conventional threaded cage designs regarding early stability and long-term stress shielding effects on ingrown bone. SUMMARY OF BACKGROUND DATA: Conventional interbody cage designs mainly fall into categories of cylindrical or rectangular shell shapes. The designs contribute to rigid stability and maintain disc height for successful arthrodesis but may also suffer mechanically mediated failures of dislocation or subsidence, as well as the possibility of bone resorption. The new optimization approach created a cage having designed microstructure that achieved desired mechanical performance while providing interconnected channels for biofactor delivery. METHODS: The topology optimization algorithm determines the material layout under desirable volume fraction (50%) and displacement constraints favorable to bone formation. A local microstructural topology optimization method was used to generate periodic microstructures for porous isotropic materials. Final topology was generated by the integration of the two-scaled structures according to segmented regions and the corresponding material density. Image-base finite element analysis was used to compare the mechanical performance of the topology-optimized cage and conventional threaded cage. RESULTS: The final design can be fabricated by a variety of Solid Free-Form systems directly from the image output. The new design exhibited a narrower, more uniform displacement range than the threaded cage design and lower stress at the cage-vertebra interface, suggesting a reduced risk of subsidence. Strain energy density analysis also indicated that a higher portion of total strain energy density was transferred into the new bone region inside the new designed cage, indicating a reduced risk of stress shielding. CONCLUSION: The new design approach using integrated topology optimization demonstrated comparable or better stability by limited displacement and reduced localized deformation related to the risk of subsidence. Less shielding of newly formed bone was predicted inside the new designed cage. Using the present approach, it is also possible to tailor cage design for specific materials, either titanium or polymer, that can attain the desired balance between stability, reduced stress shielding, and porosity for biofactor delivery.

Algorithms↗
PubMed2002

Airborne fungi and endotoxin concentrations in different areas within textile plants in Taiwan: a 3-year study.

Bioaerosols have been found in many occupational environments, including animal feeding houses, poultry slaughter houses, and cotton textile plants. This study was undertaken to examine a group of bioaerosols, the endotoxins, fungi, and bacteria, inside two textile factories over 3 years in Taiwan, where temperature and humidity are usually high year-round. Airborne dust was collected with filter cassettes attached to personal pumps and analyzed by the Kinetic Limulus Assay with Resistant-parallel-line Estimation. For fungi and bacteria determination, samples were collected using duplicated single-stage impactors, and organisms were counted after incubation. Endotoxin was the major contamination inside textile plants. Indoor levels were substantially higher than outdoor concentrations by 63- to 278-fold. The average values of fungi inside and outside the plants were not significantly different. Airborne bacteria levels were higher inside the plants as compared to outside. The carding sites, using only cotton, had extremely high endotoxin levels, greater than those at sites using synthetic fibers. Cotton, may be a major source of endotoxin contamination. In conclusion, the early stage of textile processing seems to generate high endotoxin and bacteria contamination. Priorities should be given to occupational hygiene programs for workers at various sites in textile plants.

Aerosols↗
PubMedDate not supplied

Functional bone engineering using ex vivo gene therapy and topology-optimized, biodegradable polymer composite scaffolds.

Bone tissue engineering could provide an alternative to conventional treatments for fracture nonunion, spinal fusion, joint replacement, and pathological loss of bone. However, this approach will require a biocompatible matrix to allow progenitor cell delivery and support tissue invasion. The construct must also support physiological loads as it degrades to allow the regenerated tissue to bear an increasing load. To meet these complex requirements, we have employed topology-optimized design and solid free-form fabrication to manufacture biodegradable poly(propylene fumarate)/beta-tricalcium phosphate composites. These scaffolds were seeded with primary human fibroblasts transduced with an adenovirus expressing bone morphogenetic protein-7 and implanted subcutaneously in mice. Specimens were evaluated by microcomputed tomography, compressive testing, and histological staining. New bone was localized on the scaffold surface and closely followed its designed contours. Furthermore, the total stiffness of the constructs was retained for up to 12 weeks after implantation, as scaffold degradation and tissue invasion took place.

Adenoviridae↗