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1.
ACS Appl Mater Interfaces ; 14(26): 29483-29490, 2022 Jul 06.
Article in English | MEDLINE | ID: mdl-35700238

ABSTRACT

A highly precise and sensitive technology that enables DNA amplification/detection from minimal amounts of nucleic acid is expected to find applicability in genetic testing involving small amounts of samples. The use of a free enzyme in conventional DNA amplification techniques, such as the polymerase chain reaction (PCR), frequently causes side reactions (i.e., nonspecific DNA amplification) when ≤103 substrate DNA molecules are present, thereby preventing selective amplification of the target DNA. To address this issue, we have developed a novel DNA amplification system, mesoporous silica-enhanced PCR (MSE-PCR), which involves the immobilization of a thermostable DNA polymerase from Thermococcus kodakaraensis (KOD DNA polymerase) into highly ordered nanopores of the mesoporous silica to control the reaction environment around the enzyme. In the MSE-PCR system using immobilized KOD DNA polymerase, such nonspecific DNA amplification was remarkably inhibited under the same conditions. Furthermore, the optimization of mesoporous silica pore sizes enabled selective and efficient DNA amplification from DNA substrates at the single-molecule level, i.e., one ten-thousandth of the amount of substrate DNA required for a DNA amplification reaction using a free enzyme. The results obtained in this study have shown that the nanopores of mesoporous silica can inhibit nonspecific reactions in DNA amplification, thereby considerably improving the specificity and sensitivity of the DNA polymerase reaction.


Subject(s)
Enzymes, Immobilized , Silicon Dioxide , DNA , DNA-Directed DNA Polymerase/chemistry , Enzymes, Immobilized/genetics , Immobilized Nucleic Acids/chemistry , Polymerase Chain Reaction/methods , Silicon Dioxide/chemistry
2.
J Biosci Bioeng ; 131(3): 250-255, 2021 Mar.
Article in English | MEDLINE | ID: mdl-33191128

ABSTRACT

A novel organic-inorganic hybrid porous material (KCS-2), containing both lipophilic and hydrophilic nanospaces to mimic a lipid bilayer, was utilized as an immobilization support and reaction accelerator for glutamate decarboxylase (GADß). Upon evaluation of the adsorption of GADß on KCS-2, the amount of immobilization was found to be approximately four times higher than that on non-porous silica, and a comparable adsorbability to mesoporous silica was observed. Following γ-aminobutyric acid (GABA) production by the decarboxylation of l-glutamic acid using these immobilized enzymes, the enzymatic activity of the GADß-KCS-2 composite was found to be significantly higher than that of the free enzyme. In contrast, the activity of the more common GADß-mesoporous silica composite decreased. Furthermore, the enzymatic activity of the GADß-KCS-2 composite was superior to those of the un-immobilized free enzyme and the amorphous material itself over a wide temperature range. Thereby, these findings suggest that the amphiphilic nanospace of KCS-2 is suitable as a stable enzyme immobilization field and reaction acceleration field under such conditions. In addition, the durability of the immobilized enzyme was examined in terms of GABA production, with approximately 20% activity retention being observed after 10 cycles using KCS-2. Such durability was not observed for the non-porous silica material due to enzyme desorption.


Subject(s)
Enzymes, Immobilized/chemistry , Enzymes, Immobilized/metabolism , Glutamate Decarboxylase/chemistry , Glutamate Decarboxylase/metabolism , Hydrophobic and Hydrophilic Interactions , gamma-Aminobutyric Acid/chemical synthesis , Adsorption , Glutamic Acid/chemistry , Porosity , Silicon Dioxide/chemistry
3.
JGH Open ; 4(6): 1108-1113, 2020 Dec.
Article in English | MEDLINE | ID: mdl-33319044

ABSTRACT

BACKGROUND AND AIM: TL1A (TNFSF15) is a major Crohn's disease (CD) susceptibility gene, especially in the East Asian population, and is also known to be associated with some clinical phenotypes, such as stricturing and penetrating behavior. This study aims to investigate the association between TL1A genotype and the long-term therapeutic outcomes of infliximab and adalimumab in Japanese CD patients. METHODS: We investigated 119 biologic-naïve CD patients treated with infliximab or adalimumab. TL1A -358C/T (rs6478109) was genotyped as a tag single nucleotide polymorphism (SNP) for CD risk or nonrisk haplotype of TL1A (the -358C allele is a risk allele for CD development). We compared the long-term therapeutic outcomes of anti-tumor necrosis factor (TNF) antibodies between the TL1A -358C/C group and the C/T+T/T group. RESULTS: Sixty-nine cases (58.0%) were homozygous for the risk allele (TL1A -358C/C group), and 50 cases (42.0%) were heterozygous for the risk allele or homozygous for the protective allele (TL1A -358C/T+T/T group). No significant differences were found in the cumulative retention rates and the relapse-free survival between the TL1A genotypes. However, the surgery-free survival was significantly lower in the TL1A -358C/C group than in the C/T+T/T group (log-rank test, P < 0.05). Multivariate analysis showed that TL1A -358C/C was identified as an independent risk factor for surgery (hazard ratio, 4.67; 95% confidence interval, 1.39-22.1; P = 0.025). CONCLUSION: An association was found between the TL1A genotype and the therapeutic outcomes of anti-TNF therapy. Our data indicate that the design of customized therapy with anti-TNF antibodies using TL1A genomic information could be effective in the future.

4.
Dalton Trans ; 49(37): 12960-12969, 2020 Oct 07.
Article in English | MEDLINE | ID: mdl-32936162

ABSTRACT

A newly synthesized microporous zincosilicate THK-2 (estimated structural composition: |(H2O)6.7(C6H13N)0.9|[Li0.5Zn3.1Si32O62.7(OH)9.3]) was characterized by single-crystal electron diffraction using the automated electron diffraction tomography (ADT) approach in combination with powder X-ray diffraction. The lattice constants and space group of as-synthesized THK-2 were a = 2.50377(7) nm, b = 1.43866(4) nm, c = 0.505369(8) nm, and Pccn (no. 56) with orthorhombic symmetry. Because the crystal lattice was almost identical to a hexagonal lattice (), the first several peaks in its powder X-ray diffraction data severely overlapped, which suppressed the structural information to decide the framework topology. In order to overcome this intrinsic difficulty, the structure model of THK-2 was initially obtained by the direct method based on ADT data and refined by the Rietveld method. Its 3-dimensional framework structure was elucidated and it consisted of 4-, 5-, 6-rings of tetrahedral Si and Zn atoms and a one-dimensional straight channel with a 12-ring pore opening. Zn atoms were incorporated into the framework as four-coordinated [ZnO4], although their distribution was confirmed to be disorderly. In the as-synthesized THK-2, the site occupancy of Zn was as low as 0.39; that is, more than 60% of the Zn sites were vacant. Hexamethyleneimine and water molecules were accommodated in the straight channel in a disordered manner. The material was stable upon calcination, and the BET specific surface area and micropore volume of calcined THK-2 were 240.6 m2 g-1 and 0.12 ml g-1, respectively.

5.
Inflamm Intest Dis ; 5(1): 11-19, 2020 Feb.
Article in English | MEDLINE | ID: mdl-32232050

ABSTRACT

INTRODUCTION: The long-term prognosis of Japanese patients with Crohn's disease (CD) treated by switching anti-tumor necrosis factor-α (anti-TNFα) antibodies remains unclear. OBJECTIVE: This study aimed to clarify the long-term prognosis and clinical factors that affect the long-term prognosis and outcomes of such patients. METHODS: This retrospective, observational, single-center cohort study analyzed Japanese patients with CD treated by switching between infliximab and adalimumab in the Tohoku University Hospital between March 2003 and December 2017. Cumulative relapse-free survival and cumulative surgery-free survival rates were analyzed using the Kaplan-Meier method. Clinical factors that affected the long-term outcomes were identified using both a log-rank test and the Cox proportional hazards model. RESULTS: The cumulative relapse-free survival rates were 68.6, 33.7, and 22.9% at 1, 3, and 5 years, respectively. The surgery-free survival rates were 91.7, 75.7, and 57.4% at 1, 3, and 5 years, respectively. The cumulative relapse-free survival rate was significantly higher in the group with ileal lesions (HR = 0.12; 95% CI 0.0066-0.64, p = 0.0086), stricture (HR = 0.24; 95% CI 0.0094-0.59, p = 0.0021), and a penetrating type (HR = 0.34; 95% CI 0.14-0.84, p = 0.020). Intolerance (HR = 0.29; 95% CI 0.12-0.63, p = 0.0013) and switching after surgery (HR = 0.41; 95% CI 0.17-0.87, p = 0.019) were clinical factors that reduced the risk of recurrence. The cumulative surgery-free survival rate was significantly higher in the group that switched after surgery (HR = 0.28; 95% CI 0.074-0.91, p = 0.034) and used concomitant thiopurine (HR = 0.32; 95% CI 0.10-0.90, p = 0.030). CONCLUSION: We should clarify the reason for switching anti-TNFα antibodies and investigate bowel complications before switching. Surgical reset of bowel complications including stricture and fistula could reduce the risk of recurrence after switching anti-TNFα antibodies. Concomitant thiopurine administration might reduce the risk of bowel surgery after switching anti-TNFα antibodies.

6.
RSC Adv ; 9(5): 2641-2644, 2019 Jan 18.
Article in English | MEDLINE | ID: mdl-35520522

ABSTRACT

A novel type of crystalline organic-inorganic hybrid microporous silicate material, KCS-5, was synthesized supposedly from a lamellar precursor composed of amphiphilic organosilicic acids. This well-ordered material has a crystalline structure, is thermally stable up to 500 °C and has lipophilic 1-dimensional micropores.

7.
J Crohns Colitis ; 13(5): 648-658, 2019 Apr 26.
Article in English | MEDLINE | ID: mdl-30500874

ABSTRACT

BACKGROUND AND AIMS: Genome-wide association studies [GWASs] of European populations have identified numerous susceptibility loci for Crohn's disease [CD]. Susceptibility genes differ by ethnicity, however, so GWASs specific for Asian populations are required. This study aimed to clarify the Japanese-specific genetic background for CD by a GWAS using the Japonica array [JPA] and subsequent imputation with the 1KJPN reference panel. METHODS: Two independent Japanese case/control sets (Tohoku region [379 CD patients, 1621 controls] and Kyushu region [334 CD patients, 462 controls]) were included. GWASs were performed separately for each population, followed by a meta-analysis. Two additional replication sets [254 + 516 CD patients and 287 + 565 controls] were analysed for top hit single nucleotide polymorphisms [SNPs] from novel genomic regions. RESULTS: Genotype data of 4 335 144 SNPs from 713 Japanese CD patients and 2083 controls were analysed. SNPs located in TNFSF15 (rs78898421, Pmeta = 2.59 × 10-26, odds ratio [OR] = 2.10), HLA-DQB1 [rs184950714, pmeta = 3.56 × 10-19, OR = 2.05], ZNF365, and 4p14 loci were significantly associated with CD in Japanese individuals. Replication analyses were performed for four novel candidate loci [p <1 × 10-6], and rs488200 located upstream of RAP1A was significantly associated with CD [pcombined = 4.36 × 10-8, OR = 1.31]. Transcriptome analysis of CD4+ effector memory T cells from lamina propria mononuclear cells of CD patients revealed a significant association of rs488200 with RAP1A expression. CONCLUSIONS: RAP1A is a novel susceptibility locus for CD in the Japanese population.


Subject(s)
Crohn Disease/genetics , Genetic Predisposition to Disease/genetics , rap1 GTP-Binding Proteins/physiology , Adult , Case-Control Studies , Crohn Disease/epidemiology , Female , Gene Expression Profiling , Genome-Wide Association Study , Humans , Japan/epidemiology , Male , Polymorphism, Single Nucleotide/genetics , Young Adult , rap1 GTP-Binding Proteins/genetics
8.
Intest Res ; 17(1): 94-106, 2019 Jan.
Article in English | MEDLINE | ID: mdl-30508475

ABSTRACT

BACKGROUND/AIMS: Few reports have described the long-term treatment outcomes of the anti-tumor necrosis factor-α antibody for Japanese Crohn's disease (CD) patients. The aim of this study was to evaluate them and clarify the clinical factors that affect the long-term prognosis of the anti-tumor necrosis factor-α treatments. METHODS: This was a retrospective, observational, single-center cohort study. Japanese CD patients treated with either infliximab or adalimumab as a first-line therapy were analyzed. The cumulative retention rates of the biologics, relapse-free survival, and surgery-free survival were analyzed using Kaplan-Meier methods. The clinical factors associated with the long-term outcomes were estimated by both the log-rank test and Cox proportional hazard model. RESULTS: The cumulative retention rate was significantly higher in the group with a concomitant elemental diet of ≥900 kcal/day, baseline C-reactive protein (CRP) levels <2.6 mg/dL, and baseline serum albumin levels ≥3.5 g/dL, respectively. The baseline serum albumin levels were also associated with both relapse-free and surgery-free survival. The lack of concomitant use of an elemental diet ≥900 kcal/day was identified as the only independent risk factor for the withdrawal of the biologics. CONCLUSIONS: Baseline CRP levels and serum albumin levels could affect the long-term outcomes in CD patients. Concomitant elemental diet of ≥900 kcal/day could have a positive influence on clinical treatment course.

9.
Nihon Shokakibyo Gakkai Zasshi ; 114(9): 1639-1648, 2017.
Article in Japanese | MEDLINE | ID: mdl-28883293

ABSTRACT

BACKGROUNDS AND AIMS: Peripherally inserted central catheters (PICC) have been widely used as a blood access route for total parenteral nutrition (TPN) in recent years. However, there have been few reports that evaluated the usefulness of PICC for patients with inflammatory bowel disease (IBD). In this study, we compared the clinical courses in patients with IBD who received TPN during their hospitalization by conventional central venous catheters (CVC) and PICC. PATIENTS AND METHODS: A total of 137 IBD patients were enrolled. The CVC group and the PICC group included 56 and 81 patients, respectively. The clinical courses in both groups were compared retrospectively. RESULTS: As a complication of the puncture, pneumothorax occurred in two patients (3.6%) in the CVC group, but in none (0%) in the PICC group. The PICC group had significantly higher rates of achieving the scheduled TPN without removing the catheter, lower rates of catheter-related blood stream infection (CRBSI) and longer periods without CRBSI than the CVC group. CONCLUSION: PICC might be more useful than CVC in terms of safety and the ability to deliver scheduled TPN for IBD patients.


Subject(s)
Inflammatory Bowel Diseases/therapy , Parenteral Nutrition, Total , Adult , Catheterization, Peripheral , Female , Humans , Male , Retrospective Studies
10.
Angew Chem Int Ed Engl ; 54(27): 7994-8, 2015 Jun 26.
Article in English | MEDLINE | ID: mdl-26012531

ABSTRACT

A new organic-inorganic hybrid zeotype compound with amphiphilic one-dimensional nanopore and aluminosilicate composition was developed. The framework structure is composed of double aluminosilicate layers and 12-ring nanopores; a hydrophilic layer pillared by Q(2) silicon atom species and a lipophilic layer pillared by phenylene groups are alternately stacked, and 12-ring nanopores perpendicularly penetrate the layers. The framework topology looks similar to that of an AFI-type zeolite but possesses a quasi-multidimensional pore structure consisting of a 12-ring channel and intersecting small pores equivalent to 8-rings. The hybrid material with alternately laminated lipophilic and hydrophilic nanospaces can be assumed as a crystallized Langmuir-Blodgett film. It demonstrates microporous adsorption for both hydrophilic and lipophilic adsorptives, and its outer surface tightly adsorbs lysozyme whose molecular size is much larger than its micropore opening. Our results suggest the possibility of designing porous adsorbent with high amphipathicity.

11.
Gan To Kagaku Ryoho ; 38(11): 1885-8, 2011 Nov.
Article in Japanese | MEDLINE | ID: mdl-22083204

ABSTRACT

We present a 68-year-old man suffering from transverse myelopathy since May 2010. The spinal cord MRI showed a T2- hyperintense lesion invading the Th5 level spinal cord. Although the patient transiently responded to steroid-pulse therapy, his neurological symptoms degenerated three months after wards. On admission, he had an apparent hepatosplenomegaly, but no lymphadenopathy. A laboratory examination revealed bicytopenia and increased levels ofLDH and soluble IL-2 receptors. Histological analysis ofa skin biopsy specimen demonstrated proliferation of large atypical lymphoid cells positive for CD20 and CD79a in the small capillaries, leading to our diagnosis of intravascular large B-cell lymphoma(IVLBCL). Thus, the patient's progressive myelopathy was probably caused by IVLBCL invasion. The patient responded well to Rituximab-combined CHOP therapy(R-CHOP), and his neurological symptoms improved immediately. A spinal cord MRI showed the disappearance of the abnormal signal after two courses of R -CHOP. IVLBCL often presents with neurological manifestations, including transverse myelopathy.


Subject(s)
Lymphoma, B-Cell/complications , Lymphoma, B-Cell/pathology , Spinal Cord Diseases/etiology , Aged , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Biopsy , Cyclophosphamide/therapeutic use , Doxorubicin/therapeutic use , Humans , Lymphoma, B-Cell/drug therapy , Magnetic Resonance Imaging , Male , Prednisone/therapeutic use , Tomography, X-Ray Computed , Vincristine/therapeutic use
12.
J Phys Chem B ; 111(42): 12119-23, 2007 Oct 25.
Article in English | MEDLINE | ID: mdl-17914803

ABSTRACT

A novel type of organic-inorganic hybrid zeolite with organic lattice (ZOL) is studied in detail by solid-state (13)C magic angle spinning nuclear magnetic resonance (MAS NMR). The (13)C MAS NMR measurements employing several pulse sequences quantitatively demonstrate that methylene groups are really incorporated in the framework, although they are partially cleaved into methyl groups. The organic species in ZOL materials are open for adsorbates, which is evidenced by the (13)C MAS NMR measurements for an n-hexane-adsorbing ZOL material. This finding strongly suggests that organic moieties are incorporated as a zeolite framework, indicating that ZOL is not a physical mixture of a carbon-containing amorphous aggregate and a conventional zeolite but a true organic-inorganic hybrid zeolite.

13.
J Colloid Interface Sci ; 309(1): 149-54, 2007 May 01.
Article in English | MEDLINE | ID: mdl-17362976

ABSTRACT

Metallic Ni nanoparticles were successfully prepared on the surface of titania thin film substrate by a novel method, named as chemical vapor reductive deposition (CVRD) method. The growth of the nanoparticles was based on the specific adsorption and heterogeneous nucleation on the surface of substrate, not via vapor-phase formation and subsequent sedimentation. The nanoparticle size was found to be well controllable between 10 and 30 nm by the preparation time and vapor pressure of metal complex precursor. ESCA and electron diffraction results clearly demonstrated Ni nanoparticles as metallic. Titania thin film with metallic Ni nanoparticles on its surface showed high efficiency in their photocatalysis of hydrogen evolution from decomposition of ethanol.

14.
J Phys Chem B ; 110(12): 6224-8, 2006 Mar 30.
Article in English | MEDLINE | ID: mdl-16553437

ABSTRACT

A novel preparation technique for a nanostructured anode for a solid oxide fuel cell is investigated. By mixing nanometer-sized NiO and YSZ powders in a pH-controlled aqueous media, a fine mixture of nanoparticles is successfully obtained through heterocoagulation. The anode prepared from thus prepared mixture has a large triple phase boundary and shows a great improvement in the anode performance by increasing the electric conductivity and effective surface area.

15.
Chem Commun (Camb) ; (3): 348-50, 2005 Jan 21.
Article in English | MEDLINE | ID: mdl-15645033

ABSTRACT

Single nanometer-sized metallic Ni particles have been successfully deposited inside a hexagonally ordered mesoporous silica material by using a liquid-phase reductive deposition method.

16.
Science ; 300(5618): 470-2, 2003 Apr 18.
Article in English | MEDLINE | ID: mdl-12702872

ABSTRACT

Organic-inorganic hybrid zeolite materials containing an organic framework have been synthesized by partially superseding a lattice oxygen atom by a methylene group. The use of methylene-bridged organosilane as a silicon source gives zeolite materials containing an organic group as lattice (ZOL), with several zeolitic phases such as the MFI and the LTA structures. Through various characterization methods, the presence of methylene frameworks (Si-CH2-Si) that replace siloxane bonds (Si-O-Si) has been verified, although the Si-C bonds are partly cleaved to give rise to terminal methyl groups. The shape-selective lipophilicity of a ZOL material indicates that it is not a physical mixture of conventional zeolite and amorphous organic-containing material but contains a genuine organic-inorganic hybrid zeolite.

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