Artificial cells, blood substitutes, and immobilization biotechnology最新文献

HBOC-201 may alter lipase and amylase detection on chemistry analyzers using optical methods and affect pancreatic function after trauma. Amylase and lipase measurements were correlated against HBOC-201 to evaluate interference on samples spiked with 0-6g/dL HBOC-201. The detection threshold was 2.5g/dL or none when measured, respectively, on Vitros 250 or Advia 1650 instruments. Amylase and lipase from blood samples collected from 55% EBV hemorrhaged Yucatan min-pigs showed peaks around 24-48 hours. Amylase increase was not significant between treatments but lipase was higher in HBOC-201-treated animals. Animals particularly affected by the injury had elevated enzymes after hemorrhagic shock, without significant clinical consequences.

Objective: To investigate the biocompatibility of diamond-like carbon (DLC) coated nickel-titanium shape memory alloy (NiTi SMA) in vitro and in vivo.

Methods: The in vitro study was carried out by co-culturing the DLC coated and uncoated NiTi SMA with bone marrow mesenchymal stem cells (MSCs), respectively, and the in vivo study was carried out by fixing the rabbits' femoral fracture model by DLC coated and uncoated NiTi SMA embracing fixator for 4 weeks, respectively. The concentration of the cells, alkaline phosphatase (AKP), and nickel ion in culture media were detected, respectively, at the first to fifth day after co-culturing. The inorganic substance, osteocalcin, alkaline phosphatase (ALP), and tumor necrosis factor (TNF) in callus surrounding fracture and the Ni(+) in muscles surrounding fracture site, liver and brain were detected 4 weeks postoperatively.

Results: The in vitro study showed that the proliferation of MSCs and the expression of AKP in the DLC-coated group were higher than the uncoated group (P < 0.05), while the uncoated group released more Ni(2+) into the culture media than that in the coated group (P < 0.05). The in vivo study revealed that the inorganic substance and AKP, osteocalcin, and TNF expression were significantly higher in the DLC coated NiTi SMA embracing fixator than that in the uncoated group (P < 0.05). Ni(2+) in liver, brain, and muscles surrounding the fracture were significantly lower in the DLC coated groups than that in the uncoated group (P < 0.05).

Conclusion: Nickel-titanium shape memory alloy coated by diamond-like carbon appears to have better biocompatibility in vitro and in vivo compared to the uncoated one.

A higher production of functional mast cells (MCs) can be generated by co-culturing cord blood-derived CD34+ cells with a human bone marrow stromal cell line under serum-free conditions supplemented with stem cell factor and IL-6. We addressed the question of whether the higher proliferation of MCs in this co-culture system might be due to the higher proliferation of MC progenitors. The stromal cell line increased the cell numbers of MC progenitors derived from cord blood-derived CD34+ cells, in a combination of cell-cell interactions between stromal cells and CD34+ cells, and as yet unidentified soluble factors derived from stromal cells.

Nanomaterials constitute novel and interesting matrices for enzyme immobilization. While their high surface to volume ratio is an obvious advantage, their Brownian motion can impact the behavior of enzymes immobilized on these matrices. Carbon nanotubes, superparamagnetic nanoparticles, and mesoporous materials constitute some important classes of matrices. Such immobilized enzyme systems have been used in both aqueous and low water media for biocatalysis and resolution of racemates. This overview examines the behavior of enzymes immobilized on nanomaterials and discusses the results reported with such biocatalyst preparations.

Kyphoplasty (KP) and vertebroplasty (VP) are both minimally invasive surgical techniques, which can enhance the mechanical stability of the vertebral lesion by injecting filling materials into the fractured vertebra. The filling materials used in KP and VP include injectable PMMA, composite bone cement, biodegradable bone cement, calcium phosphate cement (CPC), and others. Different filling materials have different effects on the biomechanical properties of vertebral bodies, causing various biomechanical effects on the adjacent vertebral bodies. In conclusion, the development of filling materials can improve the anti-pressure capacity and effectively maintain good morphological characteristics of fractured vertebral bodies.

This study aims to estimate the effects of using one donor nerve to repair the injured nerve and itself simultaneously by biodegradable chitin conduit. Proximal median nerve served as donor nerve to repair the distal median and whole ulnar nerve. Four months postoperation, the number of myelinated axons and nerve conduction velocities of the distal median and ulnar nerve were (2085 ± 215 and 24.4 ± 5.9 m/s), and (1193 ± 102 and 30.7 ± 11.2 m/s). Recovery of the tetanic muscle forces of the reinvervated muscles were also observed. It suggests that Dor to Dor+Rec neurorrhaphy is a practical method for severe peripheral nerve injury.

Human plasma fraction IV is an intermediate precipitate during the production of human serum albumin using cold ethanol method. Haptoglobin locates in this fraction can be purified for various applications. A new process integration of polyethylene glycol (PEG) precipitation and ion-exchange chromatography (IEC) was developed for purification of haptoglobin, which could effectively purify the haptoglobin from 16.6% to 95%. The recovery of the new process was 58.2% in comparison to 30.3% of the conventional affinity chromatography. Furthermore, 175 mg haptoglobin production in a scaled-up process showed the method to be simple, fast, and low-cost.

Various types of porous resin adsorbents based on polystyrene, agarose, and cellulose as matrixes coupling with DNA, amino acids and other biological active molecules as ligands were extensively studied in China. Molecular recognition between the ligand and pathogenic molecule was investigated. Several commercialized products are now widely used in hospitals all over China. Whole blood hemoperfusion is used to treat patients suffering from autoimmune diseases, uremia acute intoxication, and hyperbilirubinemia. Clinical performances of hundreds and thousands of patients treated by whole blood sorption therapy show that the therapy is safe, efficient, and cost-effective.

Exsanguinating hemorrhage and unavailability of blood are major problems in pre-hospital trauma care. We investigated if combining rFVIIa with HBOC-201 reduces blood loss and improves physiologic parameters compared to HBOC alone. Swine underwent liver injury and were resuscitated with HBOC-201 alone or HBOC+90, 180 or 360 μg/kg rFVIIa before hospital arrival at 240 min; animals survived to 72 hours. Blood loss was reduced; MAP, CI, transcutaneous oxygen saturation, and 72-hour survival improved in the 90 and 180 μg/kg rFVIIa groups. Lactate was cleared faster in the HBOC+rFVIIa 90 μg/kg group. Verification in a large, well-powered study is indicated.

The propensity of site-specific carboxymethylation and propylation of Val-1(α) of Hb to attenuate the reductive hexaPEGylation-induced dissociation of tetramers has been investigated. Only reductive propylation of Val-1(α), which increases the stability of oxy Hb, attenuates the reductive hexaPEGylation-induced dissociation. Increasing the stability of the oxy conformation of Hb by chemical or genetic approaches is a strategy to generate PEGylated Hbs with native-like tetramer stability using direct PEGylation platforms. This new approach and EAF-PEGylation are the only two alternate PEGylation strategies available to design stable second-generation vasoinactive uncrosslinked PEGylated Hbs with native-like tetramer stability.