[Show abstract][Hide abstract] ABSTRACT: Most types of collagen used for biomedical applications, such as cell therapy and tissue engineering, are derived from animal tissues. Therefore, special precautions must be taken during the production of these proteins in order to assure against the possibility of the products transmitting infectious diseases to the recipients. The ability to remove and/or inactivate known and potential viral contaminants during the manufacturing process is an ever-increasingly important parameter in assessing the safety of biomedical products. The purpose of this study was to evaluate the efficacies of the 70% ethanol treatment and pepsin treatment at pH 2.0 for the inactivation of bovine viruses during the manufacture of collagen type I from bovine hides. A variety of experimental model viruses for bovine viruses including bovine herpes virus (BHV), bovine viral diarrhea virus (BVDV), bovine parainfluenza 3 virus (BPIV-3), and bovine parvovirus (BPV), were chosen for the evaluation of viral inactivation efficacy. BHV, BVDV, BPIV-3, and BPV were effectively inactivated to undetectable levels within 1 h of 70% ethanol treatment for 24 h, with log reduction factors of , , , and , respectively. BHV, BVDV, BPIV-3, and BPV were also effectively inactivated to undetectable levels within 5 days of pepsin treatment for 14 days, with the log reduction factors of , , , and , respectively. The cumulative virus reduction factors of BHV, BVDV, BPIV-3, and BPV were , , , and . These results indicate that the production process for collagen type I from bovine hides has a sufficient virus-reducing capacity to achieve a high margin of virus safety.
[Show abstract][Hide abstract] ABSTRACT: Although transmission of pandemic influenza A virus H1N1 2009 is still occurring globally, little has been reported about how this outbreak has affected the safety of plasma derivatives. To evaluate the safety of plasma derivatives, dedicated virus clearance processes used during their production were investigated for their effectiveness in eliminating this virus of recent concern. In this study, influenza A virus H1N1 strain A/NWS/33 (H1N1) was chosen as a surrogate. H1N1 was completely inactivated by fraction IV fractionation as well as pasteurization during the manufacture of albumin. H1N1 was also effectively removed into the precipitate by fraction III fractionation and completely inactivated by low pH incubation as well as pasteurization during the manufacture of intravenous immunoglobulin. H1N1 was completely inactivated within 1 min of solvent/detergent treatment using 0.3% tri (n-butyl) phosphate and 1.0% Triton X-100 and also completely inactivated within 10 min of dry-heat treatment at 98 °C during the manufacture of factor VIII. H1N1 was completely removed by virus filtration process using Viresolve NFP filter and also completely inactivated by pasteurization during the manufacture of anti-thrombin III. These results indicate that all the virus clearance processes commonly used have sufficient H1N1 reducing capacity to achieve a high margin of safety.
[Show abstract][Hide abstract] ABSTRACT: E. coli has been widely used as a host system to manufacture recombinant proteins for human therapeutic use. Among impurities to be eliminated during the downstream process, residual host cell DNA is a major interest for safety. Residual E. coli host cell DNA in the final products are usually determined using conventional slot blot hybridization assay or total DNA Threshold assay, although these methods are time consuming, expensive, and relatively insensitive. Therefore a sensitive real-time PCR assay for specific detection of residual E. coli DNA was developed and compared with slot blot hybridization assay and Threshold assay to validate the overall capability of these methods. Specific primer pair for amplification of the E. coli 16S rRNA gene was selected to improve the sensitivity, and E. coli host cell DNA was quantified by use of SYBR Green 1. The detection limit of real-time PCR assay in the optimized condition was calculated to be 0.042 pg genomic DNA, which is much higher than those of slot blot hybridization assay and Threshold assay of which detection limit were 2.42 and 3.73 pg genomic DNA, respectively. The real-time PCR assay was validated to be more reproducible, accurate, and precise than slot blot hybridization assay and Threshold assay. The real-time PCR assay may be a useful tool for quantitative detection and clearance validation of residual E. coli DNA during the manufacturing process for recombinant therapeutics.
Journal of Microbiology and Biotechnology 10/2010; 20(10):1463-70. · 1.40 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Because any patient, health care worker, or visitor is capable of transmitting influenza to susceptible persons within hospitals, hospital-acquired influenza has been a clinical concern. Disinfection and cleaning of medical equipment, surgical instruments, and hospital environment are important measures to prevent transmission of influenza virus from hospitals to individuals. This study was conducted to evaluate the efficacy of disinfection processes, which can be easily operated at hospitals, in inactivating influenza A virus H1N1 (H1N1).
The effects of 0.1 mol/L NaOH, 70% ethanol, 70% 1-propanol, solvent/detergent (S/D) using 0.3% tri (n-butyl)-phosphate and 1.0% Triton X-100, heat, and ethylene oxide (EO) treatments in inactivating H1N1 were determined. Inactivation of H1N1 was kinetically determined by the treatment of disinfectants to virus solution. Also, a surface test method, which involved drying an amount of virus on a surface and then applying the inactivation methods for 1 minute of contact time, was used to determine the virucidal activity.
H1N1 was completely inactivated to undetectable levels in 1 minute of 70% ethanol, 70% 1-propanol, and solvent/detergent treatments in the surface tests as well as in the suspension tests. H1N1 was completely inactivated in 1 minute of 0.1 mol/L NaOH treatment in the suspension tests and also effectively inactivated in the surface tests with the log reduction factor of 3.7. H1N1 was inactivated to undetectable levels within 5 minutes, 2.5 minutes, and 1 minute of heat treatment at 70, 80, and 90 degrees C, respectively in the suspension tests. Also, H1N1 was completely inactivated by EO treatment in the surface tests.
Common disinfectants, heat, and EO tested in this study were effective at inactivating H1N1. These results would be helpful in implementing effective disinfecting measures to prevent hospital-acquired infections.
American journal of infection control 06/2010; 38(5):354-60. · 3.01 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: The safety of plasma derivatives has been reinforced since 1980s by variable pathogen inactivation or elimination techniques. Nucleic acid amplification test (NAT) for the source plasma has also been implemented worldwide. Recently nanofiltration has been used in some country for ensuring safety of plasma derivatives to eliminate non-enveloped viruses such as parvovirus B19 (B19V) and hepatitis A virus (HAV). We evaluated the efficacy of nanofiltration for the elimination of B19V and HAV.
To verify the efficacy of nanofiltration, we adopted a 20 nm Viresolve NFP (Millipore, USA) in the scaling down (1:1,370) model of the antithrombin III production. As virus stock solutions, we used B19V reactive plasma and porcine parvovirus (PPV) and HAV obtained from cell culture. And 50% tissue culture infectious dose was consumed as infectious dose. The methods used to evaluate the virus-elimination efficacy were reverse-transcriptase polymerase chain reaction for B19V and the cytopathic effect calculation after filtration for PPV and HAV.
B19V was not detected by RT-PCR in the filtered antithrombin III solutions with initial viral load of 6.42 x 10(5) IU/mL and 1.42 x 10(5) IU/mL before filtration. The virus-elimination efficacy of nanofiltration for PPV and HAV were > or = (3.32) and > or = (3.31), respectively.
Nanofiltration would be an effective method for the elimination of B19V and HAV. It may be used as a substitute for NAT screening of these viruses in source plasma to ensure safety of plasma derivatives in Korea.
The Korean Journal of Laboratory Medicine 02/2010; 30(1):45-50. · 0.72 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Streptomyces coelicolor produces an extracellular protease inhibitor protein, STI (Streptomyces trypsin inhibitor). We show that post-growth elimination of STI is needed for colonies to develop aerial mycelium efficiently. Inactivation of STI, and thus the normal progression of colony development, at least partly involves an extracellular protease specified by gene SCO5913. Two-hybrid analysis identified two possible targets of STI inhibition (the products of SCO1355 and SCO5447), both extracellular proteases containing a domain homologous with the P-domain of eukaryotic convertases, proteases that mediate the processing of many precursors with important cellular or developmental roles. At least the SCO1355 protease is needed for the normal progression of development. Two components of the proposed cascade are dependent on the tRNA for the rare UUA (leucine) codon, which is specified by the developmental gene bldA. A model is presented that links intracellular regulatory events with an extracellular protease cascade to facilitate normal development.
[Show abstract][Hide abstract] ABSTRACT: The purpose of this study was to evaluate the efficacy and mechanisms of the solvent/detergent (S/D) treatment, DEAE-toyopearl
650M anion-exchange column chromatography, heparin-sepharose 6FF affinity column chromatography, and Viresolve NFP filtration
steps employed in the manufacture of high-purity antihemophilic factor IX (Green-Nine VF) from human plasma, with regard to
removal and/or inactivation of blood-borne viruses. A variety of experimental model viruses for human pathogenic viruses,
including human immunodeficiency virus (HIV), bovine herpes virus (BHV), bovine viral diarrhoea virus (BVDV), hepatitis A
virus (HAV), murine encephalomyocarditis virus (EMCV), and porcine parvovirus (PPV), were all selected for this study. Samples
from relevant stages of the production process were spiked with each virus and subjected to scale-down processes mimicking
the manufacture of high-purity factor IX. Samples were collected at each step, immediately titrated using a 50% tissue culture
infectious dose (TCID50), and virus reduction factors were evaluated. S/D treatment using the organic solvent, tri (n-butyl) phosphate (TNBP), and
the detergent, Tween 80, was a robust and effective step in inactivation of enveloped viruses. Titers of HIV, BHV, and BVDV
were reduced from the initial titer of 6.06, 7.72, and 6.92 log10 TCID50, respectively, reaching undetectable levels within 1 min of S/D treatment. DEAE-toyopearl 650M anion-exchange column chromatography
was found to be a moderately effective step in the removal of HAV, EMCV, and PPV with log reduction factors of 1.12, 2.67,
and 1.38, respectively. Heparin-sepharose 6FF affinity column chromatography was also moderately effective for partitioning
BHV, BVDV, HAV, EMCV, and PPV with log reduction factors of 1.55, 1.35, 1.08, 1.19, and 1.61, respectively. The Viresolve
NFP filtration step was a robust and effective step in removing all viruses tested, since HIV, BHV, BVDV, HAV, EMCV, and PPV
were completely removed during the filtration step with log reduction factors of ≥ 5.51, ≥ 5.76, ≥ 5.18, ≥ 5.34, ≥ 6.13, and
≥ 4.28, respectively. Cumulative log reduction factors of HIV, BHV, BVDV, HAV, EMCV, and PPV were ≥ 10.52, ≥ 12.07, ≥ 10.49,
≥ 7.54, ≥ 9.99, and ≥ 7.24, respectively. These results indicate that the production process for GreenNine VF has a sufficient
virus reduction capacity for achievement of a high margin of virus safety.
Biotechnology and Bioprocess Engineering 01/2009; 14(6):716-724. · 1.28 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: A model predictive control (MPC) system has been developed for application to the condensate recycle process of a 300 MW cogeneration
power station of the East-West Power Plant, Gyeonggido, Korea. Unlike other industrial processes where MPC has been predominantly
applied, the operation mode of the cogeneration power station changes continuously with weather and seasonal conditions. Such
characteristic makes it difficult to find the process model for controller design through identification. To overcome the
difficulty, process models for MPC design were derived for each operation mode from the material balance applied to the pipeline
network around the concerned process. The MPC algorithm has been developed so that the controller tuning is easy with one
tuning knob for each output and the constrained optimization is solved by an interior-point method. For verification of the
MPC system before process implementation, a process simulator was also developed. Performance of the MPC was investigated
first with a process simulator against various disturbance scenarios.
Korean Journal of Chemical Engineering 08/2008; 25(5):972-979. · 1.06 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Viral safety is an important prerequisite for clinical preparations of plasma-derived pharmaceuticals. One potential way to increase the safety of therapeutic biological products is the use of a virus-retentive filter. In order to increase the viral safety of human antihemophilic factor IX, particularly in regard to non-enveloped viruses, virus removal process using a polyvinylidene fluoride membrane filter (Viresolve NFP) has been optimized. The most critical factor affecting the filtration efficiency was operating pH and the optimum pH was 6 or 7. Flow rate increased with increasing operating pressure and temperature. Recovery yield in the optimized production-scale process was 96%. No substantial changes were observed in the physical and biochemical characteristics of the filtered factor IX in comparison with those before filtration. A 47-mm disk membrane filter was used to simulate the process performance of the production-scale cartridges and to test if it could remove several experimental model viruses for human pathogenic viruses, including human hepatitis A virus (HAV), porcine parvovirus (PPV), murine encephalomyocarditis virus (EMCV), human immunodeficiency virus type 1 (HIV), bovine viral diarrhea virus (BVDV), and bovine herpes virus (BHV). Nonenveloped viruses (HAV, PPV, and EMCV) as well as enveloped viruses (HIV, BVDV, and BHV) were completely removed during filtration. The log reduction factors achieved were >or=6.12 for HAV, >or=4.28 for PPV, >or=5.33 for EMCV, >or=5.51 for HIV, >or=5.17 for BVDV, and >or=5.75 for BHV. These results indicate that the virus filtration process successfully improved the viral safety of factor IX.
Journal of Microbiology and Biotechnology 08/2008; 18(7):1317-25. · 1.40 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Viral safety is a prerequisite for manufacturing clinical antihemophilic factor VIII concentrates from human plasma. With particular regard to the hepatitis A virus (HAV), a terminal dry-heat treatment (100 degrees for 30 min) process, following lyophilization, was developed to improve the virus safety of a solvent/detergent-treated antihemophilic factor VIII concentrate. The loss of factor VIII activity during dry-heat treatment was of about 5%. No substantial changes were observed in the physical and biochemical characteristics of the dry-heat-treated factor VIII compared with those of the factor VIII before dry-heat treatment. The dry-heat-treated factor VIII was stable for up to 24 months at 4oC. The dry-heat treatment after lyophilization was an effective process for inactivating viruses. The HAV, murine encephalomyocarditis virus (EMCV), and human immunodeficiency virus (HIV) were completely inactivated to below detectable levels within 10 min of the dry-heat treatment. Bovine herpes virus (BHV) and bovine viral diarrhea virus (BVDV) were potentially sensitive to the treatment. However porcine parvovirus (PPV) was slightly resistant to the treatment. The log reduction factors achieved during lyophilization and dry-heat treatment were > or =5.55 for HAV, > or =5.87 for EMCV, > or =5.15 for HIV, 6.13 for BHV, 4.46 for BVDV, and 1.90 for PPV. These results indicate that dry-heat treatment improves the virus safety of factor VIII concentrates, without destroying the activity. Moreover, the treatment represents an effective measure for the inactivation of non-lipid-enveloped viruses, in particular HAV, which is resistant to solvent/detergent treatment.
Journal of Microbiology and Biotechnology 05/2008; 18(5):997-1003. · 1.40 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: The purpose of the present study was to evaluate the efficacies and mechanisms of the PAB (para-amino benzamidine) affinity
column chromatography, virus filtration, pasteurization (60°C heat treatment for 10 h), and lyophilization steps employed
in the manufacture of urokinase from human urine with regard to the removal and/or inactivation of human immunodeficiency
virus (HIV), bovine viral diarrhoea virus (BVDV), bovine herpes virus (BHV), and murine encephalomyocarditis virus (EMCV).
Samples from relevant stages of the production process were spiked with each virus and subjected to scale-down processes mimicking
the manufacture of urokinase. Samples were collected at each step, immediately titrated using a 50% tissue culture infectious
dose (TCID50), and the virus reduction factors evaluated. PAB chromatography was found to be an effective step for removing BVDV, BHV,
and EMCV with log reduction factors of 2.79, 6.50, and 5.96, respectively. HIV, BVDV, BHV, and EMCV were completely removed
during the Viresolve NFP filtration step with log reduction factors of ≥6.06, ≥4.60, ≥5.44, and ≥6.87, respectively. Pasteurization
was also found to be a robust and effective step in inactivating all the viruses tested, since there were no residual viruses
detected after the pasteurization process. The log reduction factors achieved by pasteurization were ≥5.73 for HIV, ≥3.86
for BVDV, ≥6.75 for BHV, and ≥5.92 for EMCV. Lyophilization showed significant efficacy for inactivating BVDV, BHV, and EMCV
with log reduction factors of 2.69, 1.37, and 4.70, respectively. These results indicate that the production process for urokinase
exhibited a sufficient viral reducing capacity to achieve a high margin of virus safety.
Biotechnology and Bioprocess Engineering 02/2008; 13(1):25-32. · 1.28 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: The effects of amniotic membranes (AMs), either fresh human and bovine AMs or acellular bovine AMs, on wound healing were compared among the burn wounds of porcine skin. Six pigs were chosen for the study, and we created deep second-degree contact burns on them with a digitally controlled aluminum thermal block. Then we applied the dressings to some of the wounds using fresh human and bovine AMs, acellular bovine AMs, polyurethane foam, or no dressing. We evaluated the pigs for (1) the rate of epithelialization, (2) histological grading, and (3) infections. We found that the AM groups showed better wound-healing effects than did the polyurethane foam and no dressing groups, and these differences were statistically significant. However, the differences between the AM groups were not statistically significant. Wound cultures showed higher infection rates in the control and polyurethane foam groups compared with the other groups. Our study showed that fresh or acellular bovine AMs provided similar efficacy for wound healing as did the fresh human AMs.
Wound Repair and Regeneration 01/2008; 16(4):520-8. · 2.76 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: A novel advanced control technique for the SMB process has been proposed. In the proposed technique, regulation of both extract and raffinate purities measured at the terminal time of each switching period is performed by a successive linearization-based repetitive controller which utilizes the past period data as feed back information. The repetitive controller was designed on the basis of a successively linearized model of the first-law SMB model. For this, we have first proposed a novel scheme for reduced-order ODE modeling of a convection-dominant SMB process. The linearized model for the controller design was derived from this model. Through application to a numerical SMB process, it was found that the proposed control technique performs quite satisfactorily against model error as well as set point and disturbance changes
SICE-ICASE, 2006. International Joint Conference; 11/2006
[Show abstract][Hide abstract] ABSTRACT: A novel heterotrophic, yellow pigmented, aerobic, Gram-negative, nonmotile, oxidase- and catalase-positive bacterium KMM 3,938(T) was isolated from sea water collected in the Sea of Japan, Russia. The strain grew at mesophilic temperature range, and required the presence of NaCl for growth. 16S rRNA gene sequence analysis revealed that strain KMM 3,938(T) is a member of the family Flavobacteriaceae. The predominant fatty acids were C13:0 iso, C14:0 iso, C15:0 iso, C15:0, C15:1Delta6, 3OH-C15:0:3 iso, and 3OH-C15:0. The G + C content of the DNA of KMM 3938(T) was 32.4 mol%. On the basis of phenotypic, chemotaxonomic, genotypic, and phylogenetic characteristics, the novel bacterium was assigned to the genus Polaribacter as Polaribacter butkevichii sp. nov. The type strain is KMM 3938(T )(= KCTC 12100(T) = CCUG 48005(T)).
Current Microbiology 01/2006; 51(6):408-12. · 1.52 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: A marine, heterotrophic, Gram-negative, aerobic, yellow-pigmented, bacterium that was motile by gliding, isolated from the green alga Acrosiphonia sonderi, was studied by polyphasic taxonomic methods. 16S rRNA gene sequence analysis indicated that strain KMM 6031T formed a distinct lineage within the family Flavobacteriaceae. On the basis of phenotypic, chemotaxonomic, genotypic and phylogenetic analyses, the novel bacterium was classified as Pibocella ponti gen. nov., sp. nov. The type strain is KMM 6031T (=KCTC 12262T=NBRC 100591T=LMG 22573T).
International journal of systematic and evolutionary microbiology 02/2005; 55(Pt 1):177-81. · 2.11 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: A bacterial strain, designated KMM 6049T, was isolated from the sea urchin Strongylocentrotus intermedius inhabiting the Sea of Japan. The bacterium studied was strictly aerobic, heterotrophic, yellow-pigmented, non-motile, Gram-negative and oxidase-, catalase-, beta-galactosidase- and alkaline phosphatase-positive. 16S rRNA gene sequence analysis indicated that strain KMM 3524T was closely related to Salegentibacter holothuriorum and Salegentibacter salegens (sharing 97.7 and 98 % sequence similarity, respectively). DNA-DNA relatedness levels between strains KMM 6049T and S. holothuriorum KMM 3524T and S. salegens DSM 5424T were 24 and 45 %, respectively, indicating that KMM 6049T belongs to a novel species of the genus Salegentibacter, for which the name Salegentibacter mishustinae sp. nov. is proposed. The type strain is KMM 6049T (=KCTC 12263T=LMG 22584T=NBRC 100592T).
International journal of systematic and evolutionary microbiology 02/2005; 55(Pt 1):235-8. · 2.11 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: A novel marine bacterium, strain KMM 6050T, was isolated from the sea urchin Strongylocentrotus intermedius, which inhabits the Sea of Japan. The strain studied was strictly aerobic, heterotrophic, yellow-orange-pigmented, motile by gliding, Gram-negative and oxidase-, catalase-, beta-galactosidase- and alkaline phosphatase-positive. The results of 16S rRNA gene sequence analysis showed that strain KMM 6050T occupies a distinct lineage within the family Flavobacteriaceae and is most closely related to the species Mesonia algae and Salegentibacter salegens (sequence similarity of 92.5-92.6 %). The DNA G+C content of KMM 6050T was 39.6 mol%. The major respiratory quinone was MK-6. The predominant fatty acids were i15 : 0, a15 : 0, 15 : 0, i16 : 1, i16 : 0, i16 : 0 3-OH and i17 : 0 3-OH. On the basis of phenotypic, chemotaxonomic, genotypic and phylogenetic characteristics, the novel bacterium has been assigned to the genus Gramella gen. nov., as Gramella echinicola sp. nov. The type strain is KMM 6050T (=KCTC 12278T=NBRC 100593T=LMG 22585T).
International journal of systematic and evolutionary microbiology 02/2005; 55(Pt 1):391-4. · 2.11 Impact Factor