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1.
Soft Matter ; 19(13): 2330-2338, 2023 Mar 29.
Article in English | MEDLINE | ID: mdl-36876875

ABSTRACT

Herein, we designed and synthesized a thermally stable carboxybetaine copolymer with a one- or three-carbon spacer between ammonium and carboxylate groups (CBMA1 and CBMA3) to create an anti-nonspecific adsorption surface with the ability to immobilize antibodies. A series of controlled poly(N,N-dimethylaminoethyl methacrylate) was successfully prepared using reversible addition-fragmentation chain-transfer (RAFT) polymerization and was derived to carboxybetaine copolymers of poly(CBMA1-co-CBMA3) [P(CBMA1/CBMA3)] with various CBMA1 contents, including the homopolymers of CBMA1 and CBMA3. Thermal stability of the carboxybetaine (co)polymers was higher than that of the carboxybetaine polymer with a two-carbon spacer (PCBMA2). Further, we also evaluated nonspecific protein adsorption in fetal bovine serum and antibody immobilization on the substrate coated with P(CBMA1/CBMA3) copolymers using surface plasmon resonance (SPR) analysis. As the CBMA1 content increased, nonspecific protein adsorption on the P(CBMA1/CBMA3) copolymer surface decreased. Similarly, the immobilization amount of the antibody decreased as the CBMA1 content increased. However, the figure of merit (FOM), defined as the ratio of the amount of antibody immobilization to that of nonspecific protein adsorption, depended on the CBMA3 content; FOM was higher when the CBMA3 content was 20-40% than those of CBMA1 and CBMA3 homopolymers. These findings will help enhance the sensitivity of the analysis using molecular interaction measurement devices, such as SPR and quartz crystal microbalance.


Subject(s)
Polymers , Proteins , Adsorption , Polymers/chemistry , Surface Plasmon Resonance , Methacrylates , Surface Properties
2.
Macromol Rapid Commun ; 44(4): e2200729, 2023 Feb.
Article in English | MEDLINE | ID: mdl-36443826

ABSTRACT

Photo-iniferter reversible addition-fragmentation chain transfer (PI-RAFT) polymerization of N-vinylformamide (NVF) is demonstrated by using purple light. PNVFs with predetermined molar masses and narrow molar mass distributions are obtained. High RAFT chain-end fidelity is confirmed by matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF) and electrospray-ionization time-of-flight mass spectrometry (ESI-TOF-MS), and chain extension experiment. To demonstrate the potential of this approach, an original poly(N-vinylpyrrolidone)-b-poly(N-vinylformamide) (PVP-b-PNVF) diblock copolymer is synthesized and characterized by aqueous size-exclusion chromatography (SEC), asymmetric flow field-flow fractionation (A4F), and 1 H diffusion-ordered spectroscopy nuclear magnetic resonance (1 H DOSY NMR). Finally, selective hydrolysis of PNVF block to corresponding pH-responsive poly(N-vinylpyrrolidone)-b-poly(N-vinylformamide) (PVP-b-PVAm) is performed.


Subject(s)
Polyvinyls , Polymerization , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization/methods
3.
Viruses ; 13(6)2021 06 14.
Article in English | MEDLINE | ID: mdl-34198717

ABSTRACT

In this study, we investigated severe fever with thrombocytopenia syndrome (SFTS) virus (SFTSV) infection in cats in Nagasaki, Japan. In total, 44 of 133 (33.1%) cats with suspected SFTS were confirmed to be infected with SFTSV. Phylogenetic analyses of SFTSV isolates from cats indicated that the main genotype in Nagasaki was J1 and that unique reassortant strains with J2 (S segment) and unclassified genotypes (M and L segments) were also present. There were no significant differences in virus growth in cell cultures or fatality in SFTSV-infected mice between the SFTSV strains that were isolated from recovered and fatal cat cases. Remarkably, SFTSV RNAs were detected in the swabs from cats, indicating that the body fluids contain SFTSV. To evaluate the risk of SFTSV infection when providing animal care, we further examined the seroprevalence of SFTSV infection in veterinarian staff members; 3 of 71 (4.2%) were seropositive for SFTSV-specific antibodies. Our results provide useful information on the possibility of using cats as sentinel animals and raised concerns of the zoonotic risk of catching SFTSV from animals.


Subject(s)
Cat Diseases/epidemiology , Phlebovirus , Severe Fever with Thrombocytopenia Syndrome/epidemiology , Veterinarians , Animals , Antibodies, Viral/blood , Antibodies, Viral/immunology , Cat Diseases/virology , Cats , Genome, Viral , High-Throughput Nucleotide Sequencing , Immunoglobulin G/blood , Immunoglobulin G/immunology , Japan/epidemiology , Phlebovirus/classification , Phlebovirus/genetics , Phylogeny , RNA, Viral , Severe Fever with Thrombocytopenia Syndrome/veterinary , Severe Fever with Thrombocytopenia Syndrome/virology
4.
Yakugaku Zasshi ; 140(6): 763-766, 2020.
Article in Japanese | MEDLINE | ID: mdl-32475924

ABSTRACT

The Japanese Pharmacopoeia (JP) is an official document that defines the specifications, criteria, and standard test methods necessary to properly ensure the quality of medicines in Japan. To ensure the efficacy and safety of pharmaceutical products, it is essential to establish standards that ensure their quality. For this purpose, the JP aims to include all drugs that are important from the viewpoint of healthcare and medical treatment, and description of each monograph of medicine is maintained and improved so that those standards can be generally practiced. In addition, to play a key role as the official document in the field of pharmaceutical product quality, JP contents are enhanced by proactively introducing the latest scientific knowledge and technologies. As the international manufacturing of pharmaceutical products and their raw materials that are distributed in Japan is increasing, the JP has recently begun to promote the international harmonisation of pharmaceutical excipients and general tests through the Pharmacopoeial Discussion Group (PDG) and to swiftly implement the harmonised items in the JP. In addition, the JP will implement internationally harmonised concepts and specifications for pharmaceutical products, e.g., the International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use (ICH), to define the latest concepts of quality control for pharmaceutical products in the official document. We introduce the implementation of the latest scientific knowledge, technologies, and activities for international harmonisation of the JP.


Subject(s)
Biopharmaceutics/standards , International Cooperation , Knowledge , Pharmacopoeias as Topic , Humans , Japan , Quality Control
5.
J Clin Virol ; 125: 104304, 2020 04.
Article in English | MEDLINE | ID: mdl-32145478

ABSTRACT

BACKGROUND: Sri Lanka experienced its largest dengue outbreak in 2017 with more than 185,000 dengue cases including at least 250 fatalities. OBJECTIVES: Our study aimed to characterize the clinical, immunological and virological features of confirmed dengue patients in Sri Lanka during the outbreak in 2017 when unusual manifestations of severe dengue were observed. STUDY DESIGN: Sera from 295 patients who were admitted to Teaching Hospital Kandy, Kandy, Sri Lanka between March 2017- January 2018 were subjected to NS1 antigen, IgM and IgG ELISAs, virus isolation, conventional and real time RT-PCR and next generation sequencing. RESULTS: Primary and secondary infections were detected in 48.5 % and 51.5 % of the study population, respectively. Two hundred twenty five DENV strains were isolated (219 DENV-2, one DENV-3, two DENV-4, two mixed infections of DENV-2 and -3 and one mixed infection of DENV-2 and -4). Unusual and severe manifestations such as encephalitis, encephalopathy, liver failure, kidney failure, myocarditis, Guillain-Barré syndrome and multi-organ failure were noted in 44 dengue patients with 11 deaths. The viraemia levels in patients with primary infection and unusual manifestations were significantly higher compared to those in patients with secondary infection. A new clade of DENV-2 Cosmopolitan genotype strains was observed with the strains closely related to those from China, Malaysia, Indonesia, Singapore and Taiwan. CONCLUSIONS: The new clade of DENV-2 cosmopolitan genotype observed in Sri Lanka in 2017 caused an unprecedented, severe dengue outbreak. The emergence of DENV-3 and DENV-4 in the 2017 outbreak might cause future outbreaks in Sri Lanka.


Subject(s)
Dengue Virus/genetics , Dengue/complications , Dengue/epidemiology , Nervous System Diseases/virology , Severe Dengue/epidemiology , Adolescent , Adult , Aged , Antibodies, Viral/blood , Child , Child, Preschool , Coinfection/complications , Coinfection/epidemiology , Coinfection/virology , Dengue/mortality , Dengue Virus/classification , Dengue Virus/pathogenicity , Disease Outbreaks/prevention & control , Disease Outbreaks/statistics & numerical data , Female , Genotype , Humans , Immunoglobulin M/blood , Infant , Male , Middle Aged , Nervous System Diseases/epidemiology , Phylogeny , RNA, Viral/genetics , Severe Dengue/mortality , Sri Lanka/epidemiology , Young Adult
6.
Am J Trop Med Hyg ; 102(6): 1217-1225, 2020 06.
Article in English | MEDLINE | ID: mdl-32189614

ABSTRACT

Dengue virus (DENV) infection is a major cause of morbidity and mortality in Vietnam, and the incidence is higher and more consistent in the southern part of the country. This study investigated the circulation of DENV serotypes, viremia levels, immunological status, and cytokine levels, with disease severities among children infected in 2017 in Ho Chi Minh City, Southern Vietnam. Acute and convalescent serum samples were collected from clinically diagnosed dengue children. They were confirmed to have DENV infection by NS1 antigen, IgM and IgG ELISAs, virus isolation, and conventional and real-time RT-PCR. Measurement of 10 cytokine levels was performed in the serum samples. All the children were dengue IgM positive; 28% and 72% of them had primary and secondary DENV infections, respectively, whereas 54% of those with secondary infection were children with dengue with warning signs and with severe dengue. Any or mixed infection of the four serotypes of DENV RNA was detected in 58 children. Twenty DENV strains (DENV-1 = 16 and DENV-4 = 4) were isolated. Levels of IFN-γ, TNF-α, MCP-1, IL-10, and IL-6 were significantly higher in severe dengue cases. We report the predominance of DENV-1 over other serotypes in the 2017 dengue outbreak in Southern Vietnam. Our data showed that cytokine expressions were correlated with dengue pathogenesis and may help in identifying an effective therapeutic strategy.


Subject(s)
Cytokines/blood , Dengue/blood , Dengue/epidemiology , Adolescent , Antibodies, Viral/blood , Child , Child, Preschool , Dengue/metabolism , Dengue/pathology , Disease Outbreaks , Female , Gene Expression Regulation , Humans , Immunoglobulin G/blood , Immunoglobulin M/blood , Infant , Male , Retrospective Studies , Vietnam/epidemiology
7.
J Mater Chem B ; 8(7): 1489-1495, 2020 02 19.
Article in English | MEDLINE | ID: mdl-31998931

ABSTRACT

Stimuli-responsive materials have been actively researched over the past few decades. Among such materials, spiropyran is one of the most attractive compounds because the structure and polarity of the material are dramatically changed after photo irradiation, unlike other materials. In this work, we designed and synthesized a spiropyran derivative (SpMA) with a methacryloyl group on the nitrobenzene ring of a spiropyran skeleton. The UV spectra of the newly synthesized SpMA showed the photo-isomerization of spiropyran. The maximum absorption wavelength (λmax) of SpMA was 616 nm in n-hexane, a nonpolar solvent, although λmax of SpMA was 532 nm in methanol, a polar protic solvent, which resulted in an 84 nm blue-shift. SpMA was successfully polymerized by ruthenium (Ru)-catalyzed living radical polymerization. Poly(SpMA) (PSpMA) was then spin-coated on a PET substrate in order to control the surface properties of water repellency and cell adhesion. The water repellency was decreased approximately 10° under UV irradiation, because of the polarity change of PSpMA caused by photo-isomerization from the spiropyran (SP) type to the merocyanine (MC) type. In addition, NIH3T3 cells were spread only on 6% of the surface of the PSpMA thin film after UV irradiation compared with no UV irradiation. The polarity change of PSpMA by photo-isomerization is also believed to be the reason for this behavior. As a result, we successfully synthesized a photo-controllable cell culture scaffold.


Subject(s)
Benzopyrans/pharmacology , Indoles/pharmacology , Methacrylates/pharmacology , Nitro Compounds/pharmacology , Polymers/pharmacology , Animals , Benzopyrans/chemical synthesis , Benzopyrans/chemistry , Cell Adhesion/drug effects , Cells, Cultured , Indoles/chemical synthesis , Indoles/chemistry , Methacrylates/chemistry , Mice , Molecular Structure , NIH 3T3 Cells , Nitro Compounds/chemical synthesis , Nitro Compounds/chemistry , Particle Size , Polymers/chemical synthesis , Polymers/chemistry , Positron-Emission Tomography , Surface Properties
8.
Chem Pharm Bull (Tokyo) ; 67(12): 1301-1313, 2019.
Article in English | MEDLINE | ID: mdl-31787657

ABSTRACT

A pharmacopoeia's core mission is to protect public health by creating and making available public standards to help ensure the quality of drugs. In recent years, pharmacopoeias around the world have harmonized their standards in the present context of globalized drug supply chains and markets. For example, the Pharmacopoeial Discussion Group has worked to harmonize excipient monographs and general chapters. In addition, the International Meeting of World Pharmacopoeias has been held by the WHO to discuss information exchange and international collaboration, among other topics. To contribute further to the protection of public health in the globalized drug market, we conducted a comparative study of the pharmacopoeias in Japan, Europe, and the United States. We aimed to examine current differences among the Japanese Pharmacopoeia, the European Pharmacopoeia, and the United States Pharmacopeia-National Formulary and to identify areas that require further collaboration among the three pharmacopoeias. In this study, we analyzed monographs and general chapters listed in the three pharmacopoeias. We identified the features of the monographs and general chapters listed in each pharmacopoeia, as well as differences across the pharmacopoeias. Moreover, on the basis of our findings, we suggest standards that require further collaboration among the pharmacopoeias in certain preferred areas. The comparison data produced by this study are expected to be used to develop strategies for future revisions of pharmacopoeias around the world.


Subject(s)
Chemistry, Pharmaceutical/standards , Europe , Humans , Japan , United States
9.
Emerg Infect Dis ; 25(11): 2127-2128, 2019 11.
Article in English | MEDLINE | ID: mdl-31625854

ABSTRACT

Severe fever with thrombocytopenia syndrome virus (SFTSV) can be transmitted between humans. We describe a case of severe fever with thrombocytopenia syndrome in which SFTSV RNA was detected in semen after its disappearance from serum. Our findings indicate possible sexual transmission of this emerging virus.


Subject(s)
Bunyaviridae Infections/epidemiology , Bunyaviridae Infections/virology , Phlebovirus/genetics , RNA, Viral , Semen/virology , Bunyaviridae Infections/transmission , Humans , Japan/epidemiology , Male , Middle Aged , Public Health Surveillance
10.
J Biomater Sci Polym Ed ; 30(13): 1161-1171, 2019 09.
Article in English | MEDLINE | ID: mdl-31200621

ABSTRACT

We have developed biocompatible scaffolds that enable cell fate control with visible light. The scaffolds are based on synthetic collagen-like polypeptide, poly(prolyl-hydroxyprolyl-glycyl) {poly(Pro-Hyp-Gly)} which has been used for cosmetics and other healthcare applications. Bioactive peptides were conjugated to the scaffolds via photoactivation reaction utilizing 488 nm visible light. In addition, the use of a photocleavable crosslinker enables dissociation of chemical moieties by 405 nm laser irradiation. The synthesis scheme enables optical control to attach and detach functional peptides in pre-patterned shapes. Using bone forming peptide (BFP), we demonstrate that calcium deposition by rat bone stromal cells can be directed on the scaffold. Using other signaling molecules and three-dimensional scaffolds, controlled differentiation of stem cells can be achieved by spatio-temporally specific irradiation of confocal microscope laser.


Subject(s)
Collagen/chemistry , Tissue Scaffolds/chemistry , Animals , Biocompatible Materials/chemistry , Cell Differentiation/physiology , Cells, Cultured , Rats , Stem Cells/cytology , Stem Cells/physiology , Tissue Engineering
11.
Am J Trop Med Hyg ; 100(3): 643-646, 2019 03.
Article in English | MEDLINE | ID: mdl-30628568

ABSTRACT

This study was conducted to find the burden of dengue virus (DENV) and Japanese encephalitis virus (JEV) among children under the age of 13, who presented with acute encephalitis syndrome at Mandalay Children Hospital in Myanmar in 2013. Molecular and serological investigations were performed on 123 cerebrospinal fluid (CSF) samples collected from these patients. By neutralization tests and/or virus isolation, four (3.3%) JEV- and one DENV-associated encephalitis cases (0.8%) were confirmed. Antibody titer against JEV Genotype 3 was the highest among the laboratory-confirmed JEV cases. One strain of DENV-1 with Genotype 1 was isolated from the CSF sample of the dengue encephalitis patient; this was similar to the virus circulating in the study area and neighboring countries. This study shows that flaviviruses are important pathogens causing encephalitis in Myanmar. Active disease surveillance, vector control, and vaccination programs should be enforced to reduce the morbidity and mortality caused by flavivirus encephalitis.


Subject(s)
Dengue/complications , Dengue/epidemiology , Encephalitis, Japanese/epidemiology , Antibodies, Viral/cerebrospinal fluid , Child , Child, Preschool , Dengue/cerebrospinal fluid , Dengue Virus/genetics , Encephalitis, Japanese/cerebrospinal fluid , Enzyme-Linked Immunosorbent Assay , Female , Humans , Infant , Male , Myanmar/epidemiology , Neutralization Tests , Phylogeny
12.
Virus Res ; 247: 120-124, 2018 03 02.
Article in English | MEDLINE | ID: mdl-29409678

ABSTRACT

An entomological surveillance of arboviruses was conducted in Myanmar in 2014. A total of 8357 Culex mosquito vectors were collected in the Mandalay area and virus isolation was done by using the mosquito cell line C6/36 E2. A total of eighteen strains of Culex flavivirus (CxFV) were isolated from Cx. tritaeniorhynchus, Cx. vishnui and Cx. fuscocephala. Like other insect-specific flaviviruses, CxFV can replicate only in mosquito cells but not in mammalian cells. These CxFV strains that were isolated in Japan from mosquitoes collected in Myanmar were closely related to the Wang Thong virus detected from Cx fusocephalus in Thailand and Cx.theileri flavivirus (CTFV) isolated from Cx. theileri mosquitoes in Portugal and Turkey. They encode a single open reading frame with 3357 amino acid residues. They have the characteristics of flaviviruses and have 95.62% amino acid identity with CTFV. This is the first report of CxFV in Myanmar with the characterized viral genome. This study illustrated that CxFV was circulating among the vectors of human pathogenic arboviruses in Myanmar but the impact of CxFV on other flaviviruses which are endemic in the study area still remains to be explored.


Subject(s)
Culex/virology , Flavivirus/genetics , Genome, Viral , Mosquito Vectors/virology , Viral Tropism , Animals , Epidemiological Monitoring , Flavivirus/classification , Flavivirus/isolation & purification , Host Specificity , Humans , Myanmar , Open Reading Frames , Phylogeny , Virus Replication
13.
J Tissue Eng Regen Med ; 12(3): e1360-e1369, 2018 03.
Article in English | MEDLINE | ID: mdl-28715113

ABSTRACT

Reproducing the features of the extracellular matrix is important for fabricating three-dimensional (3D) scaffolds for tissue regeneration. A collagen-like polypeptide, poly(Pro-Hyp-Gly), is a promising material for 3D scaffolds because of its excellent physical properties, biocompatibility, and biodegradability. In this paper, we present a novel photocrosslinked poly(Pro-Hyp-Gly) hydrogel as a 3D scaffold for simultaneous rat bone marrow stromal cell (rBMSC) encapsulation. The hydrogels were fabricated using visible-light photocrosslinking at various concentrations of methacrylated poly(Pro-Hyp-Gly) (20-50 mg/ml) and irradiation times (3 or 5 min). The results show that the rBMSCs encapsulated in the hydrogels survived 7 days of incubation. Calcium deposition on the encapsulated rBMSCs was assessed with scanning electron microscope observation, Alizarin Red S, and von Kossa staining. The most strongly stained area was observed in the hydrogel formed with 30 mg/ml of methacrylated poly(Pro-Hyp-Gly) with 5-min irradiation. These findings demonstrate that poly(Pro-Hyp-Gly) hydrogels support rBMSC viability and differentiation, as well as demonstrating the feasibility of using poly(Pro-Hyp-Gly) hydrogels as a cytocompatible, biodegradable 3D scaffold for tissue regeneration.


Subject(s)
Calcium/pharmacology , Cells, Immobilized/cytology , Collagen/pharmacology , Cross-Linking Reagents/pharmacology , Hydrogels/pharmacology , Light , Mesenchymal Stem Cells/cytology , Animals , Cell Proliferation/drug effects , Cell Survival/drug effects , Cells, Immobilized/drug effects , Collagen/chemical synthesis , Collagen/chemistry , Eosine Yellowish-(YS)/chemistry , Ethanolamines/chemistry , Female , Hydrogels/chemical synthesis , Hydrogels/chemistry , Mesenchymal Stem Cells/drug effects , Methacrylates/chemical synthesis , Methacrylates/chemistry , Proton Magnetic Resonance Spectroscopy , Pyrrolidinones/chemistry , Rats, Wistar , Time Factors
14.
J Biomater Sci Polym Ed ; 28(14): 1480-1496, 2017 Oct.
Article in English | MEDLINE | ID: mdl-28514893

ABSTRACT

Polyion complex (PIC) gel of poly(Pro-Hyp-Gly) was successfully fabricated by simply mixing polyanion and polycation derivatives of poly(Pro-Hyp-Gly), a collagen-like polypeptide. The polyanion, succinylated poly(Pro-Hyp-Gly), and the polycation, arginylated poly(Pro-Hyp-Gly), contain carboxy (pKa = 5.2) and guanidinium (pKa = 12.4) groups, respectively. Mixing the polyanion and the polycation at physiological pH (pH = 7.4) resulted in PIC gel. The hydrogel formation was optimum at an equimolar ratio of carboxy to guanidinium groups, suggesting that ionic interaction is the main determinant for the hydrogel formation. The hydrogel was successfully used for simultaneous rat bone marrow stromal cell encapsulation. The encapsulated cells survived and proliferated within the hydrogel. In addition, the cells exhibited different morphology in the hydrogel compared with cells cultured on a tissue culture dish as a two-dimensional (2D) control. At day one, a round morphology and homogeneous single cell distribution were observed in the hydrogel. In contrast, the cells spread and formed a fibroblast-like morphology on the 2D control. After three days, the cells in the hydrogel maintained their morphology and some of them formed multicellular aggregates, which is similar to cell morphology in an in vivo microenvironment. These results suggest that the PIC gel of poly(Pro-Hyp-Gly) can serve as a cytocompatible three-dimensional scaffold for stem cell encapsulation, supporting their viability, proliferation, and in vivo-like behavior.


Subject(s)
Biocompatible Materials/chemistry , Collagen/chemistry , Mesenchymal Stem Cells/chemistry , Animals , Capsules , Cell Survival/drug effects , Collagen/pharmacology , Gels , Mesenchymal Stem Cells/cytology , Mesenchymal Stem Cells/drug effects , Molecular Weight , Protein Conformation, beta-Strand , Rats
15.
J Tissue Eng Regen Med ; 11(3): 869-876, 2017 03.
Article in English | MEDLINE | ID: mdl-25627868

ABSTRACT

Encapsulation of stem cells into a three-dimensional (3D) scaffold is necessary to achieve tissue regeneration. Prefabricated 3D scaffolds, such as fibres or porous sponges, have limitations regarding homogeneous cell distribution. Hydrogels that can encapsulate cells such as animal-derived collagen gels need adjustment of the pH and/or temperature upon cell mixing. In this report, we fabricated a poly-ion complex (PIC) hydrogel of chitosan and succinylated poly(Pro-Hyp-Gly) and assessed its effect on cell viability after encapsulation of rat bone marrow stromal cells. PIC hydrogels were obtained successfully with a concentration of each precursor as low as 3.0-3.8 mg/ml. The maximum gelation and swelling ratios were achieved with an equal molar ratio (1:1) of anionic and cationic groups. Using chitosan acetate as a cationic precursor produced a PIC hydrogel with both a significantly greater gelation ratio and a better swelling ratio than chitosan chloride. Ammonium succinylated poly(Pro-Hyp-Gly) as an anionic precursor gave similar gelation and swelling ratios to those of sodium succinylated poly(Pro-Hyp-Gly). Cell encapsulation was also achieved successfully by mixing rat bone marrow stromal cells with the PIC hydrogel simultaneously during its formation. The PIC hydrogel was maintained in the culture medium for 7 days at 37°C and the encapsulated cells survived and proliferated in it. Although it is necessary to improve its functionality, this PIC hydrogel has the potential to act as a 3D scaffold for cell encapsulation and tissue regeneration. Copyright © 2015 John Wiley & Sons, Ltd.


Subject(s)
Cells, Immobilized/cytology , Chitosan/pharmacology , Collagen/pharmacology , Gels/pharmacology , Mesenchymal Stem Cells/cytology , Succinic Acid/chemistry , Animals , Cell Survival/drug effects , Chromatography, Gel , Circular Dichroism , Female , Mesenchymal Stem Cells/drug effects , Mesenchymal Stem Cells/metabolism , Rats, Wistar , Spectroscopy, Fourier Transform Infrared
16.
J Bone Miner Metab ; 35(4): 419-427, 2017 Jul.
Article in English | MEDLINE | ID: mdl-27565972

ABSTRACT

Currently, the only available evidence for the efficacy of once-weekly 17.5 mg risedronate in preventing vertebral fractures was obtained in a 48-week study in Japan. We performed a 156-week prospective, longitudinal, observational study to determine the efficacy of the 17.5 mg risedronate in preventing vertebral fractures. We included Japanese patients with established osteoporosis who were older than 50 years and had radiographically confirmed vertebral fractures. The primary endpoint was the incidence of vertebral fractures every 24 weeks, with the final interval spanning 36 weeks. We also calculated the change in bone mineral density of the lumbar spine (L2-4 BMD) and urinary N-telopeptide of type I collagen (u-NTX), and assessed the incidence of adverse drug reactions and the drug adherence rate. Data from 241 patients were available for analysis of vertebral fracture prevention. The incidence rate of vertebral fractures decreased in a time-dependent manner (P = 0.0006; Poisson regression analysis). The risk ratio (fracture incidence per 100 person-years in the final 36 weeks versus that in the first 24 weeks) was 0.21 (95 % confidence interval 0.08-0.55). Compared to baseline values, L2-4 BMD increased by 6.41 % at 156 weeks, while u-NTX decreased by 36 % at 24 weeks and was maintained thereafter (P < 0.0001). The incidence rate of adverse drug reactions was 9.18 %. Drug adherence rates assessed every 4 weeks were over 90 %. Our results indicate that 156 weeks of treatment with once-weekly 17.5 mg risedronate effectively reduced the risk of vertebral fracture in Japanese patients with established osteoporosis older than 50 years.


Subject(s)
Asian People , Osteoporosis/drug therapy , Risedronic Acid/administration & dosage , Risedronic Acid/therapeutic use , Spinal Fractures/epidemiology , Aged , Bone Density/drug effects , Bone Density Conservation Agents/therapeutic use , Collagen Type I/urine , Drug Administration Schedule , Female , Hip Fractures/epidemiology , Hip Fractures/prevention & control , Humans , Incidence , Japan , Longitudinal Studies , Lumbar Vertebrae/drug effects , Male , Osteoporosis/complications , Osteoporosis/physiopathology , Osteoporosis/urine , Patient Compliance , Peptides/urine , Prevalence , Prospective Studies , Risedronic Acid/adverse effects , Risk Factors , Spinal Fractures/complications , Spinal Fractures/physiopathology , Spinal Fractures/urine
17.
Clin Chem ; 61(4): 627-35, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25695852

ABSTRACT

BACKGROUND: Small molecules classified as haptens are generally measured by competitive immunoassay, which is theoretically inferior to noncompetitive sandwich immunoassay in terms of sensitivity and specificity. We created a method for developing sandwich immunoassays to measure haptens on the basis of antimetatype antibodies. METHODS: We generated antimetatype monoclonal antibodies against a hapten-antibody immunocomplex using an ex vivo antibody development system, the Autonomously Diversifying Library (ADLib) system. We selected 2 haptens, estradiol (E2) and 25-hydroxyvitamin D [25(OH)D], as analytes. Sandwich immunoassays for these 2 haptens were developed by use of a 96-well microtiter plate and a fully automated chemiluminescence analyzer, and the performances of these immunoassays were investigated. RESULTS: The developed assays exhibited sensitivity high enough to detect target haptens in serum samples. The limit of detection of the ELISA for E2 was 3.13 pg/mL, and that of the fully automated chemiluminescent enzyme immunoassay (CLEIA) system was 2.1 ng/mL for 25(OH)D. The cross-reactivity with immunoreactive derivatives was effectively improved compared with the competitive assay. The CVs for the sandwich ELISA for E2 were 4.2%-12.6% (intraassay) and 6.2%-21.8% (total imprecision). The CVs for the sandwich CLEIA for 25(OH)D were 1.0%-2.3% (intraassay) and 1.9%-3.5% (total imprecision). In particular, the sandwich CLEIA for 25(OH)D showed correlations of r = 0.99 with both LC-MS/MS and a commercially available (125)I RIA. CONCLUSIONS: Our method represents a potentially simple and practical approach for routine assays of haptens, including vitamins, hormones, drugs, and toxins.


Subject(s)
Antibodies, Monoclonal , Estradiol/blood , Haptens/blood , Immunoassay/methods , Vitamin D/analogs & derivatives , Humans , Immunoassay/standards , Limit of Detection , Sensitivity and Specificity , Vitamin D/blood
18.
Biomater Sci ; 2(9): 1172-1185, 2014 Sep 01.
Article in English | MEDLINE | ID: mdl-25485105

ABSTRACT

We demonstrate utilization of star-shaped polymers as high-density polymer brush coatings and their effectiveness to inhibit the adhesion of platelets and bacteria. Star polymers consisting of poly(2-hydroxyethyl methacrylate) (PHEMA) and/or poly(methyl methacrylate) (PMMA), were synthesized using living radical polymerization with a ruthenium catalyst. The polymer coatings were prepared by simple drop casting of the polymer solution onto poly(ethylene terephthalate) (PET) surfaces and then dried. Among the star polymers prepared in this study, the PHEMA star polymer (star-PHEMA) and the PHEMA/PMMA (mol. ratio of 71/29) heteroarm star polymer (star-H71M29) coatings showed the highest percentage of inhibition against platelet adhesion (78-88% relative to noncoated PET surface) and Escherichia coli (94-97%). These coatings also showed anti-adhesion activity against platelets after incubation in Dulbecco's phosphate buffered saline or surfactant solution for 7 days. In addition, the PMMA component of the star polymers increased the scratch resistance of the coating. These results indicate that the star-polymer architecture provides high polymer chain density on PET surfaces to prevent adhesion of platelets and bacteria, as well as coating stability and physical durability to prevent exposure of bare PET surfaces. The star polymers provide a simple and effective approach to preparing anti-adhesion polymer coatings on biomedical materials against the adhesion of platelets and bacteria.

19.
J Oleo Sci ; 63(12): 1303-8, 2014.
Article in English | MEDLINE | ID: mdl-25452267

ABSTRACT

Water-based architectural paints commonly contain either mineral oil-based or silicone-based antifoams. Mineral oil-based antifoams generally reduce the gloss of paint films; thus, silicone-based antifoams are mainly used in the field of architectural paints. The relationship between the antifoaming performance and the particle size of hydrophobic silica for mineral oil-based antifoams was investigated and a novel mineral oil-based antifoam that provided a glossy surface to the paint films equivalent to the surface obtained with silicone-based antifoams and with excellent antifoaming performance compared to silicone-based antifoams was developed. The novel mineral oil-based antifoam exhibits better performance than silicon-based antifoam, and thus the former is a perfect alternative to the latter for use in architectural paints.


Subject(s)
Antifoaming Agents/chemistry , Mineral Oil/chemistry , Paint , Silicon Dioxide/chemistry , Hydrophobic and Hydrophilic Interactions , Paint/analysis , Particle Size , Silicones , Surface Properties
20.
Nat Rev Nephrol ; 10(5): 290-6, 2014 May.
Article in English | MEDLINE | ID: mdl-24642801

ABSTRACT

The time and cost involved in bringing new drugs to the market hamper their approval. This problem is especially apparent in the case of renal diseases. Efficient drug research requires an a priori understanding of disease pathophysiology, target validation, rational and efficient drug discovery strategies and early testing of the physiological and pharmacological effects of the new agent in humans. Drug development initiated by academia benefits from international research networks and relies on internationally acceptable high-quality nonclinical data packages and bulk investigational drugs. Academics should, therefore, better understand pharmaceutical practice regulations and novel, efficient drug-development strategies. Many researchers remain unfamiliar with these areas and should collaborate with regulatory authorities to discover and validate surrogate markers for use in drug development, and to efficiently and effectively maximize the benefits and minimize the adverse effects of new drugs. The Japanese government and regulatory authorities have implemented a framework to encourage such collaborations; extension of this framework beyond its current reach is envisaged.


Subject(s)
Drug Discovery , Kidney Diseases/drug therapy , Biomarkers , Clinical Trials as Topic , Developing Countries , Drug Design , Drug Industry , Drugs, Investigational , Humans , Japan , Kidney Failure, Chronic/therapy , Public-Private Sector Partnerships , Rare Diseases/drug therapy , Renal Dialysis/economics , Renal Dialysis/trends
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