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1.
Stem Cells Int ; 2022: 2150680, 2022.
Article in English | MEDLINE | ID: mdl-36061149

ABSTRACT

Clinical trials serve as the fundamental prerequisite for clinical therapy of human disease, which is primarily based on biomedical studies in animal models. Undoubtedly, animal models have made a significant contribution to gaining insight into the developmental and pathophysiological understanding of human diseases. However, none of the existing animal models could efficiently simulate the development of human organs and systems due to a lack of spatial information; the discrepancy in genetic, anatomic, and physiological basis between animals and humans limits detailed investigation. Therefore, the translational efficiency of the research outcomes in clinical applications was significantly weakened, especially for some complex, chronic, and intractable diseases. For example, the clinical trials for human fragile X syndrome (FXS) solely based on animal models have failed such as mGluR5 antagonists. To mimic the development of human organs more faithfully and efficiently translate in vitro biomedical studies to clinical trials, extensive attention to organoids derived from stem cells contributes to a deeper understanding of this research. The organoids are a miniaturized version of an organ generated in vitro, partially recapitulating key features of human organ development. As such, the organoids open a novel avenue for in vitro models of human disease, advantageous over the existing animal models. The invention of organoids has brought an innovative breakthrough in regeneration medicine. The organoid-derived human tissues or organs could potentially function as invaluable platforms for biomedical studies, pathological investigation of human diseases, and drug screening. Importantly, the study of regeneration medicine and the development of therapeutic strategies for human diseases could be conducted in a dish, facilitating in vitro analysis and experimentation. Thus far, the pilot breakthrough has been made in the generation of numerous types of organoids representing different human organs. Most of these human organoids have been employed for in vitro biomedical study and drug screening. However, the efficiency and quality of the organoids in recapitulating the development of human organs have been hindered by engineering and conceptual challenges. The efficiency and quality of the organoids are essential for downstream applications. In this article, we highlight the application in the modeling of human neurodegenerative diseases (NDDs) such as FXS, Alzheimer's disease (AD), Parkinson's disease (PD), and autistic spectrum disorders (ASD), and organoid-based drug screening. Additionally, challenges and weaknesses especially for limits of the brain organoid models in modeling late onset NDDs such as AD and PD., and future perspectives regarding human brain organoids are addressed.

2.
Front Biosci (Landmark Ed) ; 26(10): 895-915, 2021 10 30.
Article in English | MEDLINE | ID: mdl-34719214

ABSTRACT

The epigenetic memory stored in the dynamic modifications, such as base modifications of cytosine (C) in DNA, including methylation/hydroxymethylation/demethylation, causes heritable phenotypes via regulating gene expression without alteration of DNA sequence. The process from cytosine modification to the epigenetic effect is orchestrated by complicated machinery consisting of writers, erasers, readers, and other factors. The two major forms of cytosine modification include methylcytosine (5-mC) and hydroxymethylcytosine (5-hmC). DNA methyltransferases (DNMTs) including DNMT1, DNMT3A, and DNMT3B function as writers for 5-mC. The ten-eleven translocation proteins (TET) including TET1, TET2, and TET3 in the mammalian genome are responsible for hydroxymethylation of 5-mC to generate 5-hmC, 5-formylcytosine (5-fC), and 5-carboxylcytosine (5-caC). The 5-mC and 5-hmC have become the two most extensively investigated epigenetic markers, and the dynamic balance of these two markers shape the landscape of the epigenome, functioning as a platform to regulate gene expression epigenetically. The landscape of the 5-hmC in epigenome is precisely and tightly regulated during the development. Aberrant alterations of the epigenetic regulation may cause severe consequences such as phenotype change as well as initiation of disease. Progressively, significant achievements have been made in characterization of writers, erasers, and readers of 5-mC and 5-hmC, as well as the contribution of aberrant alteration of 5-hmC/5-mC landscape to the pathogenesis of human diseases, such as cancers and neurological disorders. This article will highlight the research advances in the distinct contribution of TET proteins as suppressors or promoters to the pathogenesis of tumorigenesis and progression. Furthermore, this article also discusses the challenges and the directions for research in the future.


Subject(s)
5-Methylcytosine , Neoplasms , Animals , DNA Methylation , Epigenesis, Genetic , Humans , Mixed Function Oxygenases/genetics , Neoplasms/genetics , Proto-Oncogene Proteins/genetics , Proto-Oncogene Proteins/metabolism
3.
Ann Clin Lab Sci ; 50(1): 99-106, 2020 Jan.
Article in English | MEDLINE | ID: mdl-32161018

ABSTRACT

Ankylosing spondylitis (AS) is known as a microbiome-driven disease; however, the current understanding of microbiota dynamics in AS is limited. In the present study, we conducted a 16S rDNA sequence-based microbiota survey of 97 fecal samples from healthy subjects and AS patients at baseline, 1, 3 and 6 months after anti-TNF-α treatment to demonstrate the dynamic characteristic variations of gut microbiota in AS patients. The goal of this experiment is to explore the values of gut microbiota as biomarkers of disease activity and therapeutic responses to anti-TNF-α. We found that the relative abundance of microbiota in AS patients treated with anti-TNF-α differed at various time points and distinguished 4 groups: the higher and lower than healthy control (HC) level groups throughout the study and the unchanged and restored to HC levels groups. The characteristic increases of microbes in AS patients were f_Prevotellaceae and f_Actinomycetaceae In HC, the characteristic increase was f_Lachnospiraceae BASDAI positively correlated with the relative abundance of g_Escherichina-Shigella and g_Klebsiella, but negatively correlated with f_Lachnospiraraceae at baseline. (r=0.544, P=0.013, r=0.509, P=0.022 and r=-0.577, P=0.008, respectively). The beta-diversity of microbiota in AS at baseline was lower than HC at the same level (P<0.01) and restored to normal values one month after treatment. In conclusion, the variation of gut microbiota is dynamic. Therefore, some microbes can be used as indicators for monitoring disease activity and therapeutic responsiveness during treatment.


Subject(s)
Adalimumab/therapeutic use , Bacteria/classification , Biodiversity , Biomarkers/analysis , Gastrointestinal Microbiome/drug effects , Spondylitis, Ankylosing/microbiology , Tumor Necrosis Factor-alpha/antagonists & inhibitors , Adult , Anti-Inflammatory Agents/pharmacology , Bacteria/genetics , Bacteria/isolation & purification , Case-Control Studies , Feces/microbiology , Follow-Up Studies , Humans , Male , Prognosis , Prospective Studies , Severity of Illness Index , Spondylitis, Ankylosing/drug therapy , Spondylitis, Ankylosing/pathology
4.
Clin Rheumatol ; 39(9): 2653-2661, 2020 Sep.
Article in English | MEDLINE | ID: mdl-32219620

ABSTRACT

OBJECTIVES: This study aimed to investigate the relationship among smoking, TNF-α-blocker therapy, and the dynamic changes in gut microbiota in patients with ankylosing spondylitis (AS). METHODS: Using a 16S rRNA sequence, 98 fecal samples of 20 AS patients collected after 0, 1, 3 and 6 months of anti-TNF-α treatment and from 20 matched health controls were examined. The variation in composition, abundance, and diversity of gut microbiota was analyzed. The dynamic effects of smoking and treatment on gut microbiota and therapeutic efficacy in AS patients were studied. RESULTS: The increased relative abundance of microbiota in AS nonsmokers was g_Comamonas and g_Desulfovibrio, while that in AS smokers was g_Actinomyces, g_Collinsella, g_Lachnospiraceae_UCG-008, and g_Paraprevotella. The relative abundance of gut microbiota showed dynamic variation. The improvement rate of ASDAS in AS nonsmokers was higher than that in AS smokers (2.297 vs 1.736) after anti-TNF-α treatment. The ß-diversity of gut microbiota in AS smokers was lower than that in AS nonsmokers and improved with treatment. CONCLUSIONS: Both smoking and TNF-α-blocker had significant effects on the composition, relative abundance, and diversity of gut microbiota in AS patients. The AS smokers characteristically shared g_Collinsella and g_Dorea. The relative abundance of gut microbiota revealed high variability and was in dynamic fluctuation during treatment. The response of gut microbiota to anti-TNF-α treatment was found to be heterogeneous and selective. AS nonsmokers showed a greater improvement rate of ASDAS-CRP with treatment than AS smokers did. The AS smokers showed a lower ß-diversity of gut microbiota, and improved after treatment. Key Points • Characterized the dynamic variation in gut microbiota in AS patients classified as smokers and nonsmokers during treatment with anti-TNF-α. • Confirmed the interaction between smoking, anti-TNF-α therapy, and gut microbiota.


Subject(s)
Gastrointestinal Microbiome , Spondylitis, Ankylosing , Humans , RNA, Ribosomal, 16S/genetics , Smoking , Spondylitis, Ankylosing/drug therapy , Tumor Necrosis Factor-alpha
5.
Clin Rheumatol ; 38(11): 3275-3280, 2019 Nov.
Article in English | MEDLINE | ID: mdl-31372853

ABSTRACT

BACKGROUND: Long non-coding RNA (lncRNA) growth arrest specific transcript 5 (GAS5) negatively regulates interleukin-18 (IL-18) in ovarian cancer, while IL-18 contributes to the development of rheumatoid arthritis (RA). Therefore, GAS5 may also participate in RA. METHODS: GAS5 and IL-18 in plasma of RA patients (n = 60) and healthy controls (n = 60) were measured by RT-qPCR and ELISA, respectively. Linear regression was performed to analyze the correlations between plasma levels of IL-18 and GAS5 in both RA patients and healthy controls. RESULTS: In the present study, we found that plasma GAS5 was downregulated, while IL-18 was upregulated in RA patients than in healthy controls. A significant and inverse correlation between GAS5 and IL-18 was found in RA patients but not in healthy controls. IL-18 treatment did not significantly alter the expression of GAS5 in fibroblast-like synoviocytes, while GAS5 overexpression led to the inhibited expression of IL-18. GAS5 overexpression also resulted in the promoted apoptosis of fibroblast-like synoviocytes. CONCLUSIONS: Therefore, GAS5 overexpression may improve RA by downregulating IL-18 and inducing the apoptosis of fibroblast-like synoviocytes. Key points • The present study mainly showed that overexpression of GAS5 may assist the treatment of RA. • The mechanism of GAS5 for the treatment of RA involves the downregulating inflammatory IL-18 and mediating the apoptosis of fibroblast-like synoviocytes. • GAS5 and IL-8 were correlated in RA patients but not in healthy controls.


Subject(s)
Apoptosis , Arthritis, Rheumatoid/blood , Interleukin-18/blood , RNA, Long Noncoding/blood , Synoviocytes/metabolism , Adult , Aged , Female , Humans , Male , Middle Aged
6.
J Cell Biochem ; 120(9): 16254-16263, 2019 09.
Article in English | MEDLINE | ID: mdl-31087698

ABSTRACT

Rheumatoid arthritis (RA) is an autoimmune disease of the joints characterized by synovial hyperplasia and chronic inflammation. Fibroblasts-like synoviocytes (FLS), major cells in the synovium, together with infiltrated leukocytes, contribute greatly to RA progression. In our study, we hypothesized that geldanamycin (GA), a cancer drug might be able to inhibit RA FLS growth. To test the idea, RA FLS were isolated and cultured for cancer drug test. The results showed that GA can specifically inhibit the growth of RA FLS compared with normal FLS. Essentially, GA was found to promote reactive oxygen species production in RA FLS and induce programmed cell death. The annexinV/propidium iodide and terminal deoxynucleotidyl transferase dUTP nick-end labeling staining confirmed that GA can directly induce apoptosis and subsequently inhibit the growth of RA FLS, which was also confirmed by Western blot assay. In addition, our data demonstrated that inflammation was inhibited by suppressed nuclear factor κB signaling pathway. The therapeutic effect of GA was explored in collagen-induced arthritis mice. In short, GA was a promising drug for the treatment of RA by specifically inhibiting the proliferation and inflammation of RA FLS.


Subject(s)
Arthritis, Rheumatoid/drug therapy , Benzoquinones/administration & dosage , Lactams, Macrocyclic/administration & dosage , NF-kappa B/metabolism , Synoviocytes/cytology , Animals , Arthritis, Rheumatoid/metabolism , Benzoquinones/pharmacology , Case-Control Studies , Cell Proliferation/drug effects , Cell Survival/drug effects , Disease Models, Animal , Humans , Lactams, Macrocyclic/pharmacology , Male , Mice , Reactive Oxygen Species/metabolism , Signal Transduction/drug effects , Synoviocytes/drug effects , Synoviocytes/metabolism
7.
Clin Rheumatol ; 37(1): 199-204, 2018 Jan.
Article in English | MEDLINE | ID: mdl-28871338

ABSTRACT

The objective of this study is to evaluate the efficacy of single intra-articular (IA) injection of tumor necrosis factor α (TNFα) inhibitor in knee joints comparing with subcutaneous injection in rheumatoid arthritis (RA) patients. Forty-eight RA patients with 73 knee arthritis were divided into three groups, group A: received a single injection of TNF inhibitor into knee joints; group B: received regular subcutaneous injection; and group C: received both of the regimen as groups A and B. Ultrasound, erythrocyte sedimentation rate, C-reactive protein (CRP), patients' global visual analogue scale (VAS), and 28-joint Disease Activity Score (DAS28) were collected pre- and post-therapy 4 weeks. The results of the study are as follows: (1) CRP, VAS, and DAS28 of all groups improved significantly post-therapy (p < 0.05); (2) After therapy, synovial hypertrophy (SH) decreased significantly from 4.40 ± 1.86 mm to 2.74 ± 1.88 mm (p < 0.05) and power Doppler (PD) signal decreased significantly from 2.63 ± 0.75 to 1.50 ± 0.93 (p < 0.01) in group A. Synovial effusion (SE), SH, and PD showed no significant improvement in group B. SE decreased significantly from 9.84 ± 4.70 mm to 5.89 ± 4.47 mm (p < 0.05), SH decreased significantly from 4.52 ± 1.97 mm to 2.49 ± 1.73 mm (p < 0.01), and PD decreased significantly from 2.46 ± 0.66 to 1.38 ± 1.04 (p < 0.01) in group C; and (3) The improvement rate of SH and PD in both groups A and C was obviously higher than that of group B (p < 0.05). Single IA injection of TNFα inhibitor was an effective treatment in improvement of SH and PD of knee joints than subcutaneous injection in RA patients.


Subject(s)
Antirheumatic Agents/administration & dosage , Arthritis, Rheumatoid/drug therapy , Knee Joint/drug effects , Tumor Necrosis Factor-alpha/antagonists & inhibitors , Adult , Antirheumatic Agents/therapeutic use , Arthritis, Rheumatoid/diagnostic imaging , Female , Humans , Injections, Intra-Articular , Injections, Subcutaneous , Knee Joint/diagnostic imaging , Male , Middle Aged , Synovial Membrane/diagnostic imaging , Synovial Membrane/drug effects , Treatment Outcome , Ultrasonography, Doppler
8.
Clin Rheumatol ; 36(6): 1369-1377, 2017 Jun.
Article in English | MEDLINE | ID: mdl-28474138

ABSTRACT

This study aims to investigate the effect of iguratimod, a novel disease-modifying antirheumatic drug, alone or combined with methotrexate (MTX), on the serum levels of regulators of bone remodeling (receptor activator of nuclear factor-κB ligand (RANKL), osteoprotegerin (OPG), and Dickkopf-1 (DKK-1)) and bone remodeling markers (C-telopeptide of type I collagen (CTX-I) and procollagen type I N-terminal propeptide (PINP)) in patients with rheumatoid arthritis (RA). Patients with RA were treated with iguratimod, MTX, or their combination for 12 months. Serum samples were collected before treatment and 6 and 12 months afterwards. RANKL, OPG, DKK-1, CTX-I, and PINP levels were measured, and radiographic progression was assessed. The serum RANKL levels decreased after treatment for 6 and 12 months with iguratimod (median: baseline 565.00 pmol/L vs. 6 months 411.00 pmol/L vs. 12 months 212.00 pmol/L), MTX (median: baseline 562.50 pmol/L vs. 6 months 399.50 pmol/L vs. 12 months 163.50 pmol/L), and their combination (median: baseline 971.00 pmol/L vs. 6 months 272.50 pmol/L vs. 12 months 241.50 pmol/L). Combination therapy showed greater effects 6 months post-treatment compared to single-drug therapy. PINP levels increased significantly 12 months post-treatment with all therapies, but only the combination therapy led to decreased CTX-I levels. OPG and DKK-1 levels showed no significant changes. The three treatments showed no significant differences in radiographic progression. Iguratimod could stimulate bone formation and regulate the RANKL/RANK/OPG system rather than DKK-1levels. Its effects are comparable to those of MTX, and combination therapy showed stronger effects.


Subject(s)
Antirheumatic Agents/therapeutic use , Arthritis, Rheumatoid/drug therapy , Bone Remodeling/drug effects , Chromones/therapeutic use , Methotrexate/therapeutic use , Sulfonamides/therapeutic use , Adult , Antirheumatic Agents/pharmacology , Arthritis, Rheumatoid/blood , Arthritis, Rheumatoid/diagnostic imaging , Biomarkers/blood , Bone and Bones/metabolism , Chromones/pharmacology , Drug Therapy, Combination , Female , Humans , Male , Methotrexate/pharmacology , Middle Aged , Sulfonamides/pharmacology
9.
Int J Clin Exp Med ; 8(5): 7809-15, 2015.
Article in English | MEDLINE | ID: mdl-26221333

ABSTRACT

OBJECTIVE: To investigate, whether interleukin (IL)-34 can be used as marker for treatment effectiveness in rheumatoid arthritis (RA). METHODS: Serum samples were collected from 35 healthy participants and 83 patients with RA before as well as 4 weeks and 12 weeks after treatment initiation with the tumor necrosis factor α (TNF-α) inhibitor Etanercept. Related clinical data and hand radiograms of the patients were evaluated and serum IL-34, IL-6, IL-8, TNF-α, matrix metalloproteinase-3 (MMP-3) in addition to anti-cyclic citrullinated peptide (CCP) antibody concentrations were measured by ELISA. RESULTS: Serum concentrations of IL-34, IL-6, IL-8, TNF-α, MMP-3 and anti-CCP antibodies were markedly elevated in RA patients compared with controls (P<0.001), significantly decreased during treatment and correlated with erythrocyte sedimentation rate (ESR), C-reactive protein (CRP) and RA disease activity (P<0.05). IL-34 correlated withIL-6, IL-8, TNF-α, MMP-3 and anti-CCP antibodies in RA patients at baseline (P<0.01) and also with IL-8, MMP-3, IL-6, and DAS28 changes during therapy. Patients in stage III of hand X-ray RA scores had higher IL-34 serum concentrations than in stage II (P<0.05). IL-34 level decreased significantly (P<0.01) starting from 4 weeks after therapy initiation. CONCLUSIONS: IL-34 serum concentrations correlated with inflammatory cytokines before and during therapy and were significantly higher in stage III of hand X-ray score patients than in stage II participants. IL-34 might be used both as a biomarker for RA diagnosis and therapy efficiency.

10.
Clin Rheumatol ; 34(6): 1025-30, 2015 Jun.
Article in English | MEDLINE | ID: mdl-25750183

ABSTRACT

Adiponectin is divided into high-molecular-weight (HMW), medium-molecular-weight (MMW), and low-molecular-weight (LMW) forms. These forms differ not only in the number of adiponectin molecules but also in their biological activity. There are conflicting findings regarding the role of adiponectin in rheumatoid arthritis (RA). Moreover, few reports have described the relationships between serum adiponectin multimers levels and RA. Therefore, we examined the association of total adiponectin and its multimers with RA. Two study groups were examined: 180 recently diagnosed untreated RA patients with disease duration less than 1 year (RA group) and 160 age- and sex-matched control subjects (control group). RA-related factors, blood pressure, body mass index, glucose, complete lipid profile, and adiponectin multimers were measured. The levels of total adiponectin and each multimer of adiponectin were significantly lower in the RA than in the control (P < 0.01). Serum levels of total, HMW, MMW, and LMW were positively correlated with triglycerides levels and negatively correlated with the Disease Activity Score for 28 joints (DAS28). Multivariate regression analysis showed that total, HMW, and MMW adiponectin were independently associated with serum triglycerides level. LMW adiponectin was independently correlated with serum triglycerides level and DAS28. The decreased LMW adiponectin levels may be associated with disease activity of RA.


Subject(s)
Adiponectin/blood , Arthritis, Rheumatoid/blood , Multiprotein Complexes/metabolism , Adult , Female , Humans , Middle Aged , Molecular Weight , Severity of Illness Index , Triglycerides/blood
11.
Oncol Res Treat ; 37(4): 204-8, 2014.
Article in English | MEDLINE | ID: mdl-24732645

ABSTRACT

BACKGROUND: The aim of this study was to evaluate patient characteristics and findings after mammary ductoscopy in an effort to reduce the pain experienced during the procedure. PATIENTS AND METHODS: We evaluated outpatients in whom mammary ductoscopy was performed under local or intraductal anesthesia without preference, and their clinical characteristics and findings were recorded. Average and maximum pain scores were determined after the examination for statistical analysis. RESULTS: The overall average pain score was 3.74 ± 1.353, and the maximum pain score was 6.40 ± 1.681. The type of anesthesia, total operation time, nipple retraction, and discharge status significantly correlated with the pain score. Intraductal anesthesia lowered the average pain score by 0.60, whereas a total procedure time greater than 12 min increased the average pain score by 0.956. The pain score decreased if patients had nipple retraction, and intraductal anesthesia proved suitable for patients with normal nipples. CONCLUSION: Intraductal anesthesia is suitable for most patients, and ductoscopy should not exceed 12 min to minimize the pain. Nipple retraction does not significantly increase pain, but local anesthesia should be used in patients with retracted nipples. Patient age, breastfeeding history, menstrual stage, and presence of intraductal tumors were not associated with the level of pain experienced.


Subject(s)
Breast Neoplasms/pathology , Breast Neoplasms/surgery , Endoscopy/adverse effects , Mammary Glands, Human/pathology , Pain Measurement , Pain/diagnosis , Pain/etiology , Adult , Aged , Breast Neoplasms/complications , Endoscopy/methods , Female , Humans , Middle Aged , Treatment Outcome , Young Adult
12.
Clin Dev Immunol ; 2013: 342869, 2013.
Article in English | MEDLINE | ID: mdl-23983767

ABSTRACT

OBJECTIVE: To investigate the relationship between Brachial-ankle pulse wave velocity (baPWV), and its associated risk factors in Chinese patients with RA. METHODS: 138 Chinese RA patients and 150 healthy subjects were included. baPWV of all the participants was measured. RA related factors were determined, as well as traditional cardiovascular risk factors. RESULTS: baPWV was significant higher in RA group (1705.44 ± 429.20 cm/s) compared to the healthy control group (1386.23 ± 411.09 cm/s) (P < 0.001). Compared with low baPWV group, high baPWV group patients were significantly older (P = 0.008) and taller (P = 0.033). Serum cholesterol (P = 0.035), triglycerides (P = 0.004), and LDL level (P = 0.006) were significantly higher in high baPWV group patients compared with low baPWV group patients. The baPWV of RA patients was positively correlated with age (r = 0.439, P < 0.001), and serum cholesterol level (r = 0.231, P = 0.035), serum triglycerides level (r = 0.293, P < 0.001), serum LDL level (r = 0.323, P = 0.003). Meanwhile, baPWV negatively correlated with the height of RA patients (r = -0.253, P = 0.043). Multivariate regression analysis showed that baPWV of RA group was independently associated with age and serum triglycerides level. CONCLUSIONS: The old age and high level of serum triglycerides may be the major determinants of arterial stiffness in Chinese RA patients.


Subject(s)
Ankle Brachial Index , Arthritis, Rheumatoid/diagnosis , Pulse Wave Analysis , Adult , Female , Humans , Male , Middle Aged , Risk Factors , Vascular Stiffness
13.
Enzyme Microb Technol ; 51(1): 40-6, 2012 Jun 10.
Article in English | MEDLINE | ID: mdl-22579389

ABSTRACT

Lipase from Burkholderia cepacia was encapsulated inside zirconia particles by biomimetic mineralization of K2ZrF6 induced with protamine, a natural cationic protein. Scanning electron microscopy (SEM), transmission electron microscopy (TEM), and Fourier transform infrared spectroscopy (FT-IR) were employed for the characterization of the novel immobilized lipase. SEM and TEM images showed that both the zirconia particles with and without lipase have good spherical structures with average particle sizes of 150 nm. Fluorescence microscopy demonstrated that the lipase was indeed encapsulated inside the zirconia particles. The maximum immobilization capacity of the zirconia particles was 0.15 units/mg under optimum immobilization conditions. Biochemical characterization showed that the encapsulated lipase could retain most of its initial activity. Compared with free lipase, the encapsulated lipase exhibited improved thermal, pH, and recycling stabilities. After 8 weeks of storage, no substantial loss in catalytic activity was observed for the encapsulated lipase. The conversion of the kinetic resolution of (R,S)-1-phenylethanol with vinyl acetate as acetyl donor catalyzed by zirconia-immobilized lipase reached 49.9% with higher ee(s) of 99.9% under the following optimal conditions: octane as solvent, 0.1M (R,S)-1-phenylethanol, 70 mg immobilized lipase, 180 rpm, 50 °C for 48 h. After 6 cycles (288 h), the conversion and ee(s) were still 43% and 85%, respectively.


Subject(s)
Benzyl Alcohols/isolation & purification , Enzymes, Immobilized/chemistry , Enzymes, Immobilized/metabolism , Lipase/chemistry , Lipase/metabolism , Bacterial Proteins/chemistry , Bacterial Proteins/metabolism , Benzyl Alcohols/chemistry , Biomimetic Materials , Burkholderia cepacia/enzymology , Enzyme Stability , Kinetics , Microscopy, Electron, Scanning , Microscopy, Electron, Transmission , Particle Size , Spectroscopy, Fourier Transform Infrared , Stereoisomerism , Vinyl Compounds , Zirconium
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