ABSTRACT
BACKGROUND: We developed a porous Ti alloy/PEEK composite interbody cage by utilizing the advantages of polyetheretherketone (PEEK) and titanium alloy (Ti alloy) in combination with additive manufacturing technology. METHODS: Porous Ti alloy/PEEK composite cages were manufactured using various controlled porosities. Anterior intervertebral lumbar fusion and posterior augmentation were performed at three vertebral levels on 20 female pigs. Each level was randomly implanted with one of the five cages that were tested: a commercialized pure PEEK cage, a Ti alloy/PEEK composite cage with nonporous Ti alloy endplates, and three composite cages with porosities of 40, 60, and 80%, respectively. Micro-computed tomography (CT), backscattered-electron SEM (BSE-SEM), and histological analyses were performed. RESULTS: Micro-CT and histological analyses revealed improved bone growth in high-porosity groups. Micro-CT and BSE-SEM demonstrated that structures with high porosities, especially 60 and 80%, facilitated more bone formation inside the implant but not outside the implant. Histological analysis also showed that bone formation was higher in Ti alloy groups than in the PEEK group. CONCLUSION: The composite cage presents the biological advantages of Ti alloy porous endplates and the mechanical and radiographic advantages of the PEEK central core, which makes it suitable for use as a single implant for intervertebral fusion.
Subject(s)
Spinal Fusion , Titanium , Animals , Benzophenones , Bone Development , Female , Ketones , Lumbar Vertebrae/diagnostic imaging , Lumbar Vertebrae/surgery , Polyethylene Glycols , Polymers , Porosity , Swine , X-Ray MicrotomographyABSTRACT
Developing a robust, novel method for performing multiple reactions in a single tube is not only time- and cost-saving but also critical for future high-throughput whole-slide in situ techniques on diseased tissues. In this study, we introduce the use of perfluorocarbons and compound-coated magnetic particles to create pseudochambers in a single tube, allowing different reactions to be performed in different phases. Perfluorocarbons also serve as cell lysis buffer and polymerase chain reaction (PCR) buffer owing to their highly penetrating, repellent and emulsifiable properties. Using this method, nucleic acids can be isolated and purified from various sample types and sizes, followed by PCR, real-time PCR, or multiplex PCR in the same tube. No incubation or enzyme digesting time is needed and the risk of cross-contamination is reduced. Tests can be performed in microemulsions (water-in-oil droplets) containing sequence-specific captures and probes for further high-throughput detection. We present a simple, quick, and robust procedure as a prerequisite step to future high-throughput in situ techniques.
Subject(s)
Fluorocarbons , Polymerase Chain Reaction/methods , Animals , Humans , Mice , Multiplex Polymerase Chain Reaction , Nucleic Acid Amplification Techniques , Real-Time Polymerase Chain ReactionABSTRACT
The preparation of a DAPI (4',6-diamidino-2-phenylindole) derivative is described. The resulting derivative retains the fluorogenic property upon binding to double-stranded DNA. Its ability for bioconjugation through amide linkage is demonstrated.
Subject(s)
Fluorescent Dyes/chemistry , Indoles/chemistry , Serum Albumin, Bovine/chemistry , Animals , Binding Sites , Cattle , Fluorescent Dyes/chemical synthesis , Indicators and ReagentsABSTRACT
Atrazine is widely used as a herbicide in agriculture and has been identified as a major groundwater contaminant in the US. Because of the possible hazard associated with its usage, there is a need for an efficient and economic screening method for on-site field testing of atrazine and other s-triazine herbicides in soil and water. We have developed a rapid, on-site test for the detection of atrazine based on the principle of microparticle agglutination inhibition immunoassay. The test detects 50 microg kg(-1) (0.050 ppm) atrazine in soil samples with direct extraction and 1.0 microg L(-1) atrazine in water samples when coupled with solid phase extraction.
Subject(s)
Atrazine/analysis , Environmental Pollutants/analysis , Herbicides/analysis , Immunoassay/methodsABSTRACT
The preparation of several model vinylsulfamides is described. Their excellent selective reactivity towards sulfhydryl group with regards to amino group has been demonstrated by the kinetics study between a model vinylsulfamide and cysteine or lysine at different pHs.
