The prognostic role of pre-treatment neutrophil to lymphocyte ratio and platelet to lymphocyte ratio in esophageal squamous cell carcinoma treated with concurrent chemoradiotherapy.

PURPOSE: In this study, we retrospectively investigated the prognostic role of pre-treatment neutrophil to lymphocyte ratio (NLR) and platelet to lymphocyte ratio (PLR) in esophageal squamous cell carcinoma patients (ESCC) treated with concurrent chemo-radiotherapy (CCRT). METHODS: We retrospectively analyzed the records of 338 patients with pathologically diagnosed esophageal squamous cell carcinoma that underwent concurrent chemo-radiotherapy from January 2013 to December 2017. Univariate and multivariate analyses were used to identify prognostic factors for progression free survival (PFS) and overall survival (OS). RESULTS: The result showed that the thresholds for NLR and PLR were 2.47 and 136.0 by receiver operating characteristic curve. High NLR and PLR were both associated with tumor length (P < 0.05). High NLR and PLR were significantly associated with poor PFS and OS. Multivariate analyses identified NLR, PLR and TNM stage were independent risk factors for PFS and OS. CONCLUSIONS: We show that the pre-treatment NLR and PLR may serve as prognostic indicators for esophageal squamous cell carcinoma treated with concurrent chemo-radiotherapy.

Microwave ablation combined with vertebral augmentation under real-time temperature monitoring for the treatment of painful spinal osteogenic metastases.

OBJECTIVE: To evaluate the safety and efficacy of computed tomography (CT)-guided microwave ablation combined with vertebral augmentation under real-time temperature monitoring in the treatment of painful osteogenic spinal metastases. METHODS: This retrospective study included 38 patients with 63 osteogenic metastatic spinal lesions treated using CT-guided microwave ablation and vertebral augmentation under real-time temperature monitoring. Visual analog scale scores, daily morphine consumption, and Oswestry Disability Index scores were used to evaluate efficacy of the treatment. RESULTS: Microwave ablation combined with vertebral augmentation reduced the mean visual analog scale scores from 6.40 ± 1.90 preoperatively to 3.32 ± 0.96 at 24 h, 2.24 ± 0.91 at 1 week, 1.92 ± 1.32 at 4 weeks, 1.79 ± 1.45 at 12 weeks, and 1.39 ± 1.12 at 24 weeks postoperatively (all p < 0.001). The mean preoperative daily morphine consumption was 108.95 ± 56.41 mg, which decreased to 50.13 ± 25.46 mg at 24 h, 31.18 ± 18.58 mg at 1 week, 22.50 ± 16.63 mg at 4 weeks, 21.71 ± 17.68 mg at 12 weeks, and 17.27 ± 16.82 mg at 24 weeks postoperatively (all p < 0.001). During the follow-up period, the Oswestry Disability Index scores significantly reduced (p < 0.001). Bone cement leakage occurred in 25 vertebral bodies, with an incidence of 39.7% (25/63). CONCLUSIONS: The results indicate that microwave ablation combined with vertebral augmentation under real-time temperature monitoring is a feasible, effective, and safe treatment for painful osteoblast spinal metastases.

Efficacy and safety of CT-guided 125I seed implantation by coplanar template as a salvage therapy for vertebral metastases after failure of external beam radiation therapy: a retrospective study.

Purpose: To evaluate the efficacy safety of computed tomography (CT)-guided 125I seed implantation by coplanar template for vertebral metastases after failure of external beam radiation therapy (EBRT). Material and methods: Retrospective analysis of the clinical outcomes of 58 patients with vertebral metastases after failure of EBRT, who underwent 125I seed implantation as a salvage treatment with a CT-guided coplanar template-assisted technique from January 2015 to January 2017. Results: The mean post-operative NRS score decreased significantly at T4w (3.5 ± 0.9, p<0.01), T8w (2.1 ± 0.9, p<0.01), T12w (1.5 ± 0.7, p< 0.01) and T6m (1.2 ± 0.6, p< 0.01) respectively. The local control rates after 3, 6, 9 and 12 months were 100% (58/58), 93.1% (54/58), 87.9% (51/58), and 81% (47/58), respectively. The median overall survival time was 18.52months (95% CI, 16.24-20.8), and 1- and 2-year survival rates were 81% (47/58) and 34.5% (20/58), respectively. By performing a paired t-test analysis, there was no significant difference in D90, V90, D100, V100, V150, V200, GTV volume, CI, EI and HI between preoperative and postoperative (p>0.05). Conclusions: 125I seed implantation can be used as a salvage treatment for patients with vertebral metastases after failure of EBRT.

Development and manufacturability assessment of chemically-defined medium for the production of protein therapeutics in CHO cells.

Advantages of using internally developed chemically-defined (CD) media for cell culture-based therapeutic protein production over commercial media include better raw material control and medium vendor options, and most importantly, flexibility for process development and subsequent optimization needed for therapeutic protein production. Through several rounds of design of experiment (DOE) screening, and medium component supplementation and optimization studies, we successfully developed a CD basal medium (CDM) for CHO cell culture. The internally prepared liquid CDM demonstrated comparable cell culture performance to that from a commercially available control medium. However, when the same CDM formulation was transferred to two major commercial medium suppliers for manufacturing, cell culture performance utilizing these newly prepared media was significantly reduced compared with the in-house prepared counterpart. An investigation was launched to assess whether key medium components were sensitive to large-scale preparation of the final bulk media by the vendors. Further work necessitated the reformulation of the original CDM formulation into a core medium that was suitable for large-scale media manufacturing. The modified preparation of the core medium with two separate supplements to generate the final CDM was able to recover the expected cell culture performance and monoclonal antibody (mAb) productivity. Confirmation of cell culture robustness in cell growth and production was corroborated in two additional mAb-expressing cell lines. This work demonstrates that a robust CD medium is not only one that performs during the development stage, but also one that must be reproducible by commercial media vendors.

Case Study: an accelerated 8-day monoclonal antibody production process based on high seeding densities.

This study describes the development work to shorten the monoclonal antibody (mAb) production time in CHO cell cultures from 14 days to 8 days without impacting mAb titer or product quality. The proposed process increases cell inoculation densities up to 25× higher than a typical seeding density in the final production bioreactor, with the implementation of an ATF™ perfusion system in the N - 1 stage. Similar antibody titer and N-glycosylation profiles were reached in 8 days using the 25× seed condition, as in 14 days using the 1× seed condition. Acidic variants in the 25× seed condition were 12-20% lower than the 1× seed condition. These results indicate that an accelerated 8-day antibody production process utilizing a 25× seeding strategy has the potential of achieving similar product quality and titer as the 1× seeding condition in a 14-day production process.

Role of iron and sodium citrate in animal protein-free CHO cell culture medium on cell growth and monoclonal antibody production.

Chemically defined iron compounds were investigated for the development of animal protein-free cell culture media to support growth of CHO cells and production of monoclonal antibodies (mAb). Using a multivessel approach of 96-well plates, shake flasks, and bioreactors, we identified iron and its chemical partner citrate as critical components for maintenance of continuous cell growth and mAb production. The optimized iron concentration range was determined to be 0.1-0.5 mM and that for citrate 0.125-1 mM. This complete formulation is able to maintain cell growth to similar levels as those supplemented with iron compounds alone; however, mAb productivity was enhanced by 30-40% when citrate was present. The addition of sodium citrate (SC) did not affect product quality as determined by size exclusion chromatography, ion exchange chromatography, reversed phase and normal phase-HPLC. No significant changes in glucose and lactate profiles, amino acid utilization, or mAb heavy and light chain expression ratios were observed. Cellular ATP level was ∼30% higher when SC was included suggesting that SC may have a role in enhancing cellular energy content. When cell lysates were analyzed by LC-MS to assess the overall cellular protein profile, we identified that in the SC-containing sample, proteins involved in ribosome formation and protein folding were upregulated, and those functions in protein degradation were downregulated. Taken together, this data demonstrated that iron and citrate combination significantly enhanced mAb production without altering product quality and suggested these compounds had a role in upregulating the protein synthetic machinery to promote protein production.

Enzyme-linked immunosorbent assay of Escherichia coli O157:H7 in surface enhanced poly(methyl methacrylate) microchannels.

A novel surface treatment method was developed to enhance polymer-based microchannel enzyme-linked immunosorbent assay (ELISA) for Escherichia coli O157:H7 detection. By applying an amine-bearing polymer, poly(ethyleneimine) (PEI), onto poly(methyl methacrylate) (PMMA) surface at pH higher than 11, PEI molecules were covalently attached and their amine groups were introduced to PMMA surface. Zeta potential analysis and X-ray photoelectron spectroscopy (XPS) demonstrated that the alkali condition is preferable for PEI attachment onto the PMMA surface. The amine groups on the PMMA surface were then functionalized with glutaraldehyde, whose aldehyde groups served as the active sites for binding the antibody by forming covalent bonds with the amine groups of the protein molecules. This surface modification greatly improved antibody binding efficiency and the microchannel ELISA for E. coli O157:H7 detection. Compared with untreated PMMA microchannels, approximately 45 times higher signal and 3 times higher signal/noise ratio were achieved with the PEI surface treatment, which also shortened the time required for cells to bind to the microchannel surface to approximately 2 min, much less than that usually required for the same ELISA carried out in 96-well plates. The detection in the microchannel ELISA only required 5-8 cells per sample, which is also better than 15-30 cells required in multi-well plates. With the high sensitivity, short assay time, and small reagent consumption, the microchannel ELISA can be economically used for fast detection of E. coli O157:H7.

New valve and bonding designs for microfluidic biochips containing proteins.

Two major concerns in the design and fabrication of microfluidic biochips are protein binding on the channel surface and protein denaturing during device assembly. In this paper, we describe new methods to solve these problems. A "fishbone" microvalve design based on the concept of superhydrophobicity was developed to replace the capillary valve in applications where the chip surface requires protein blocking to prevent nonspecific binding. Our experimental results show that the valve functions well in a CD-like ELISA device. The packaging of biochips containing pre-loaded proteins is also a challenging task since conventional sealing methods often require the use of high temperatures, electric voltages, or organic solvents that are detrimental to the protein activity. Using CO2 gas to enhance the diffusion of polymer molecules near the device surface can result in good bonding at low temperatures and low pressure. This bonding method has little influence on the activity of the pre-loaded proteins after bonding.

Microfluidic enzyme-linked immunosorbent assay technology.

In this chapter, we have presented an overview of microfluidic enzyme-linked immunosorbent assay (ELISA) by first introducing the principle of immunoassay, ELISA, and microfabricated devices, followed by a discussion of microfabrication technology and the characterization of microfluidic components. Significant advances in laboratory technology are contributing to the further understanding of microfluidic function, surface modification and immobilization, which lead to the development of improved biomolecule detection methods and prospective applications. For the future, the exploitation of more robust-manufacturing processes and integrated assay systems in an automatic fashion with much reduced assay time and reagent consumption will allow for the effective detection and quantification of biological agents that are of interest in medical diagnostics, food safety surveillance, and environmental monitoring.

Surface modification for enhancing antibody binding on polymer-based microfluidic device for enzyme-linked immunosorbent assay.

A novel surface treatment method using poly(ethyleneimine) (PEI), an amine-bearing polymer, was developed to enhance antibody binding on the poly(methyl methacrylate) (PMMA) microfluidic immunoassay device. By treating the PMMA surface of the microchannel on the microfluidic device with PEI, 10 times more active antibodies can be bound to the microchannel surface as compared to those without treatment or treated with the small amine-bearing molecule, hexamethylenediamine (HMD). Consequently, PEI surface modification greatly improved the immunoassay performance of the microfluidic device, making it more sensitive and reliable in the detection of IgG. The improvement can be attributed to the spacer effect as well as the functional amine groups provided by the polymeric PEI molecules. Due to the smaller dimensions (140x125 microm) of the microchannel, the time required for antibody diffusion and adsorption onto the microchannel surface was reduced to only several minutes, which was 10 times faster than the similar process carried out in 96-well plates. The microchip also had a wider detection dynamic range, from 5 to 1000 ng/mL, as compared to that of the microtiter plate (from 2 to 100 ng/mL). With the PEI surface modification, PMMA-based microchips can be effectively used for enzyme linked immunosorbent assays (ELISA) with a similar detection limit, but much less reagent consumption and shorter assay time as compared to the conventional 96-well plate.

Biotransformation of R-2-hydroxy-4-phenylbutyric acid by D-lactate dehydrogenase and Candida boidinii cells containing formate dehydrogenase coimmobilized in a fibrous bed bioreactor.

R-2-hydroxy-4-phenylbutyric acid (R-HPBA) is an important intermediate in the manufacture of angiotensin converting enzyme inhibitors. In this work, a recombinant D-lactate dehydrogenase (LDH) was used to transform 2-oxo-4-phenylbutyric acid (OPBA) to R-HPBA, with concomitant oxidation of beta-nicotinamide adenine dinucleotide (NADH) to NAD(+). The cofactor NADH was regenerated by formate dehydrogenase (FDH) present in whole cells of Candida boidinii, which were pre-treated with toluene to make them permeable. The whole cells used in the process were more stable and easier to prepare as compared with the isolated FDH from the cells. Kinetic study showed that the reaction rate was dependent on the concentration of cofactor, NAD(+), and that both R-HPBA and OPBA inhibited the reaction. A novel method for co-immobilization of whole cells and LDH enzyme on cotton cloth was developed using polyethyleneimine (PEI), which induced the formation of PEI-enzyme-cell aggregates and their adsorption onto cotton cloth, leading to multilayer co-immobilization of cells and enzyme with high loading (0.5 g cell and 8 mg LDH per gram of cotton cloth) and activity yield ( > 95%). A fibrous bed bioreactor with co-immobilized cells and enzyme on the cotton cloth was then evaluated for R-HPBA production in fed-batch and repeated batch modes, which gave relatively stable reactor productivity of 9 g/L . h and product yield of 0.95 mol/mol OPBA when the concentrations of OPBA and R-HPBA were less than 10 g/L.