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1.
J Biophotonics ; : e202400138, 2024 Jul 01.
Article in English | MEDLINE | ID: mdl-38952169

ABSTRACT

Neurological disorders such as Parkinson's disease (PD) often adversely affect the vascular system, leading to alterations in blood flow patterns. Functional near-infrared spectroscopy (fNIRS) is used to monitor hemodynamic changes via signal measurement. This study investigated the potential of using resting-state fNIRS data through a convolutional neural network (CNN) to evaluate PD with orthostatic hypotension. The CNN demonstrated significant efficacy in analyzing fNIRS data, and it outperformed the other machine learning methods. The results indicate that judicious input data selection can enhance accuracy by over 85%, while including the correlation matrix as an input further improves the accuracy to more than 90%. This study underscores the promising role of CNN-based fNIRS data analysis in the diagnosis and management of the PD. This approach enhances diagnostic accuracy, particularly in resting-state conditions, and can reduce the discomfort and risks associated with current diagnostic methods, such as the head-up tilt test.

2.
Neurophotonics ; 8(2): 025013, 2021 Apr.
Article in English | MEDLINE | ID: mdl-34179215

ABSTRACT

Significance: We propose a customized animal-specific head cap and an near-infrared spectroscopy (NIRS) system to obtain NIRS signals in mobile small animals. NIRS studies in mobile small animals provide a feasible solution for comprehensive brain function studies. Aim: We aim to develop and validate a multichannel NIRS system capable of performing functional brain imaging along with a closed-box stimulation kit for small animals in mobile conditions. Approach: The customized NIRS system uses light-weight long optical fibers, along with a customized light-weight head cap to securely attach the optical fibers to the mouse. A customized stimulation box was designed to perform various stimuli in a controlled environment. The system performance was tested in a visual stimulation task on eight anesthetized mice and eight freely moving mice. Results: Following the visual stimulation task, we observed a significant stimulation-related oxyhemoglobin (HbO) increase in the visual cortex of freely moving mice during the task. In contrast, HbO concentration did not change significantly in the visual cortex of anesthetized mice. Conclusions: We demonstrate the feasibility of a wearable, multichannel NIRS system for small animals in a less confined experimental design.

3.
Neurophotonics ; 7(4): 045006, 2020 Oct.
Article in English | MEDLINE | ID: mdl-33163544

ABSTRACT

Significance: Cerebral oxygenation changes in the superior, middle, and medial gyri were used to elucidate spatial impairments of autonomic hemodynamic recovery during the head-up tilt table test (HUTT) in Parkinson's disease (PD) patients with orthostatic intolerance (OI) symptoms. Aim: To analyze dynamic oxygenation changes during the HUTT and classify PD patients with OI symptoms using clinical and oxygenation features. Approach: Thirty-nine PD patients with OI symptoms [10: orthostatic hypotension (PD-OH); 29: normal HUTT results (PD-NOR)] and seven healthy controls (HCs) were recruited. Prefrontal oxyhemoglobin (HbO) changes during the HUTT were reconstructed with diffuse optical tomography and segmented using the automated anatomical labeling system. Decision trees were used for classification. Results: HCs and PD-NOR patients with positive rates of HbO change (PD-POS) showed the greatest HbO recovery in the superior frontal gyrus (SFG) during tilt. PD-OH and PD-NOR patients with negative rates of HbO change (PD-NEG) showed asymmetric reoxygenation. The classification accuracy was 89.4% for PD-POS versus PD-NEG, 71% for PD-NOR versus PD-OH, and 55.8% for PD-POS versus PD-NEG versus PD-OH. The oxygenation features were more discriminative than the clinical features. Conclusions: PD-OH showed decreased right SFG function, which may be associated with impaired compensatory autonomic responses to orthostatic stress.

4.
Int Immunopharmacol ; 86: 106726, 2020 Sep.
Article in English | MEDLINE | ID: mdl-32593157

ABSTRACT

Patrineolignan B (PB), a lignan compound isolated from the radix and rhizomes of Patrinia scabra, was previously reported to possess a strong tumor-specific cytotoxic activity and beneficial effects on nitric oxide (NO) levels in macrophages induced by lipopolysaccharide (LPS). In this study, we assessed the effects of PB on LPS-induced inflammation in RAW 264.7 cells and clarified its molecular mechanisms. PB reversed LPS-induced increase in NO levels and prostaglandin E2 (PGE2) production, as well as inducible NO synthase (iNOS) and cyclooxygenase-2 (COX-2) protein and mRNA levels in macrophages. Besides, PB prevented the secretion of pro-inflammatory cytokines, such as tumor necrosis factor-α (TNF-α), interleukin (IL)-1ß, and IL-6 in a concentration-dependent manner. The regulatory effects of PB on LPS-induced inflammatory mediators and overproduction of pro-inflammatory cytokines were shown to depend partly on the suppression of nuclear factor kappa B (NF-κB)-mediated transcription and AP-1 activation regulated by a c-Jun amino-terminal kinase (JNK) and extracellular signal-regulated kinases (ERK). Its anti-inflammatory activity was also mediated by regulating the phosphorylation of Janus kinase (JAK)/signal transducers and activators of transcription 1/3 (STAT1/3) signaling pathway. Taken together, our results suggest that PB exhibits anti-inflammatory potency through interfering with the NF-κB, AP-1, and JAK/STAT signaling pathway in LPS-stimulated macrophages.


Subject(s)
Anti-Inflammatory Agents/pharmacology , Janus Kinases/metabolism , Lignans/pharmacology , NF-kappa B p50 Subunit/metabolism , Patrinia/chemistry , STAT Transcription Factors/metabolism , Transcription Factor AP-1/metabolism , Animals , Cyclooxygenase 2/metabolism , Cytokines/metabolism , Dinoprostone/metabolism , Extracellular Signal-Regulated MAP Kinases/metabolism , Inflammation/chemically induced , Inflammation/drug therapy , Inflammation Mediators/metabolism , JNK Mitogen-Activated Protein Kinases/metabolism , Lipopolysaccharides/toxicity , Macrophages/drug effects , Mice , Nitric Oxide/metabolism , Nitric Oxide Synthase Type II/metabolism , RAW 264.7 Cells , Signal Transduction/drug effects
5.
Neurophotonics ; 7(2): 025002, 2020 Apr.
Article in English | MEDLINE | ID: mdl-32411811

ABSTRACT

Significance: Monitoring of cerebral perfusion rather than blood pressure changes during a head-up tilt test (HUTT) is proposed to understand the pathophysiological effect of orthostatic intolerance (OI), including orthostatic hypotension (OH), in Parkinson's disease (PD) patients. Aim: We aim to characterize and distinguish the cerebral perfusion response to a HUTT for healthy controls (HCs) and PD patients with OI symptoms. Approach: Thirty-nine PD patients with OI symptoms [10 PD patients with OH (PD-OH) and 29 PD patients with normal HUTT results (PD-NOR)], along with seven HCs participated. A 108-channel diffuse optical tomography (DOT) system was used to reconstruct prefrontal oxyhemoglobin (HbO), deoxyhemoglobin (Hb), and total hemoglobin (HbT) changes during dynamic tilt (from supine to 70-deg tilt) and static tilt (remained tilted at 70 deg). Results: HCs showed rapid recovery of cerebral perfusion in the early stages of static tilt. PD-OH patients showed decreasing HbO and HbT during dynamic tilt, continuing into the static tilt period. The rate of HbO change from dynamic tilt to static tilt is the distinguishing feature between HCs and PD-OH patients. Accordingly, PD-NOR patients were subgrouped based on positive-rate and negative-rate of HbO change. PD patients with a negative rate of HbO change were more likely to report severe OI symptoms in the COMPASS questionnaire. Conclusions: Our findings showcase the usability of DOT for sensitive detection and quantification of autonomic dysfunction in PD patients with OI symptoms, even those with normal HUTT results.

6.
Phytomedicine ; 68: 153167, 2020 Mar.
Article in English | MEDLINE | ID: mdl-32028186

ABSTRACT

BACKGROUND: The roots of Partrinia scabra have been used as a medicinal herb in Asia. We previously reported that the inhibitory effect of patriscabrin F on lipopolysaccharide (LPS)-induced nitric oxide (NO) production was the most potent than that of other isolated iridoids from the roots of P. scabra. PURPOSE: We investigated the anti-inflammatory activity of patriscabrin F as an active compound of P. scabra and related signaling cascade in LPS-activated macrophages. METHOD: The anti-inflammatory activities of patriscabrin F were determined according to its inhibitory effects on NO, prostaglandin E2 (PGE2), and pro-inflammatory cytokines. The molecular mechanisms were revealed by analyzing nuclear factor-κB (NF-κB), activator protein-1 (AP-1), interferon regulatory factor 3 (IRF3), and Janus kinase (JAK)/signal transducer and activator of transcription (STAT) pathway. RESULTS: Patriscabrin F inhibited the LPS-induced production of NO, PGE2, tumor necrosis factor-α (TNF-α), interleukin (IL)-1ß, and IL-6 in both bone-marrow derived macrophages (BMDMs) and RAW 264.7 macrophages. Patriscabrin F downregulated LPS-induced inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2), TNF-α, IL-1ß, and IL-6 at the transcriptional level. Patriscabrin F suppressed LPS-induced NF-κB activation by decreasing p65 nuclear translocation, inhibitory κBα (IκBα) phosphorylation, and IκB kinase (IKK)α/ß phosphorylation. Patriscabrin F attenuated LPS-induced AP-1 activity by inhibiting c-Fos phosphorylation. Patriscabrin F suppressed the LPS-induced phosphorylation of IRF3, JAK1/JAK2, and STAT1/STAT3. CONCLUSION: Taken together, our findings suggest patriscabrin F may exhibit anti-inflammatory properties via the inhibition of NF-κB, AP-1, IRF3, and JAK-STAT activation in LPS-induced macrophages.


Subject(s)
Inflammation/drug therapy , Inflammation/metabolism , Iridoids/pharmacology , Macrophages/drug effects , Patrinia/chemistry , Animals , Cyclooxygenase 2/metabolism , Down-Regulation/drug effects , Inflammation/pathology , Interferon Regulatory Factor-3/metabolism , Iridoids/therapeutic use , Lipopolysaccharides/toxicity , Macrophages/metabolism , Mice , Mice, Inbred C57BL , NF-kappa B/metabolism , Nitric Oxide/metabolism , Nitric Oxide Synthase Type II/metabolism , Plant Roots/chemistry , RAW 264.7 Cells , STAT1 Transcription Factor/metabolism , STAT3 Transcription Factor/metabolism , Transcription Factor AP-1/metabolism
7.
J Nat Prod ; 82(12): 3379-3385, 2019 12 27.
Article in English | MEDLINE | ID: mdl-31747281

ABSTRACT

A new flavone glucoside, acacetin-7-O-(3″-O-acetyl-6″-O-malonyl)-ß-d-glucopyranoside (1), two new phenolic glucosides, (3R,7R)-tuberonic acid-12-O-[6'-O-(E)-feruloyl]-ß-d-glucopyranoside (14) and salicylic acid-2-O-[6'-O-(E)-feruloyl]-ß-d-glucopyranoside (15), and two new phenylpropanoid glucosides, chavicol-1-O-(6'-O-methylmalonyl)-ß-d-glucopyranoside (17) and chavicol-1-O-(6'-O-acetyl)-ß-d-glucopyranoside(18), as well as 26 known compounds, 2-13, 16, and 19-31, were isolated from the aerial parts of Agastache rugose. The structures of the new compounds were established by spectroscopic/spectrometric methods such as HRESIMS, NMR, and ECD. The anti-inflammatory effect of the isolated compounds was evaluated by measuring their inhibitory activities on prostaglandin E2 (PGE2) in lipopolysaccharide (LPS)-treated RAW 264.7 macrophages. New compounds 1, 15, 17, and 18 inhibited LPS-induced PGE2 production with IC50 values of 16.8 ± 0.8, 33.9 ± 4.8, 14.3 ± 2.1, and 48.8 ± 4.4 µM, respectively. Compounds 5, 7, 9-11, 13, 19, 20, 22, and 27-30 showed potent inhibitory activities with IC50 values of 1.7-8.4 µM.


Subject(s)
Agastache/chemistry , Dinoprostone/biosynthesis , Lipopolysaccharides/pharmacology , Macrophages/drug effects , Plant Components, Aerial/chemistry , Plant Extracts/pharmacology , Animals , Mice , Molecular Structure , RAW 264.7 Cells , Spectrum Analysis/methods
8.
Chem Asian J ; 14(18): 3173-3180, 2019 Sep 16.
Article in English | MEDLINE | ID: mdl-31340087

ABSTRACT

The so-called colloidal template synthesis has been applied to the preparation of surface-engineered nanoadsorbents. Colloidal microporous organic network nanotemplates (C-MONs), which showed a high surface area (611 m2 g-1 ) and enhanced microporosity, were prepared through the networking of organic building blocks in the presence of poly(vinylpyrrolidone) (PVP). Owing to entrapment of the PVP in networks, the C-MONs showed good colloidal dispersion in EtOH. MoS2 precursors were incorporated into the C-MONs and heat treatment afforded core-shell-type C@MoS2 nanoparticles with a diameter of 80 nm, a negative zeta potential (-39.5 mV), a high surface area (508 m2 g-1 ), and excellent adsorption performance towards cationic dyes (qmax =343.6 and 421.9 mg g-1 for methylene blue and rhodamine B, respectively).

9.
Eur J Med Chem ; 180: 253-267, 2019 Oct 15.
Article in English | MEDLINE | ID: mdl-31310917

ABSTRACT

Herein, we address repurposing hybrids of mosloflavone or 5,6,7-trimethoxyflavone with amide analogs of resveratrol from anticancer leads to novel potent anti-inflammatory chemical entities. To unveil the potent anti-inflammatory molecules, biological evaluations were initiated in LPS-induced RAW 264.7 macrophages at 1 µM concentration. Promising compounds were further evaluated at various concentrations. Multiple proinflammatory mediators were assessed including NO, PGE2, IL-6, TNF-α and IL-1ß. Compound 5z inhibited the induced production of NO, PGE2, IL-6, TNF-α and IL-1ß at the low 1 µM concentration by 44.76, 35.71, 53.48, 29.39 and 41.02%, respectively. Compound 5z elicited IC50 values as low as 2.11 and 0.98 µM against NO and PGE2 production respectively. Compounds 5q and 5g showed potent submicromolar IC50 values of 0.31 and 0.59 µM respectively against PGE2 production. Reverse docking of compound 5z suggested p38-α MAPK, which is a key signaling molecule within the pathways controlling the transcription of proinflammatory mediators, as the molecular target. Biochemical testing confirmed these compounds as p38-α MAPK inhibitors explaining its potent inhibition of proinflammatory mediators' production. Collectively, the results presented 5z as a promising compound for further development of anti-inflammatory agents for treatment of macrophages-and/or immune mediated inflammatory diseases.


Subject(s)
Anti-Inflammatory Agents, Non-Steroidal/pharmacology , Flavones/pharmacology , Flavonoids/pharmacology , Inflammation Mediators/metabolism , Protein Kinase Inhibitors/pharmacology , Resveratrol/pharmacology , p38 Mitogen-Activated Protein Kinases/antagonists & inhibitors , Animals , Anti-Inflammatory Agents, Non-Steroidal/chemical synthesis , Anti-Inflammatory Agents, Non-Steroidal/chemistry , Dose-Response Relationship, Drug , Drug Discovery , Flavones/chemistry , Flavonoids/chemistry , Inflammation/drug therapy , Inflammation/metabolism , Macrophages/drug effects , Macrophages/metabolism , Mice , Molecular Structure , Protein Kinase Inhibitors/chemical synthesis , Protein Kinase Inhibitors/chemistry , RAW 264.7 Cells , Resveratrol/chemistry , Structure-Activity Relationship , p38 Mitogen-Activated Protein Kinases/metabolism
10.
Chem Biol Interact ; 309: 108718, 2019 Aug 25.
Article in English | MEDLINE | ID: mdl-31211952

ABSTRACT

We have previously reported the isolation of four compounds, caffeoyloxy-5,6-dihydro-4-methyl-(2H)-pyran-2-one (CDMP), olinioside, caffeic acid and 3-hydroxylup-12-en-28-oic acid, from the leaves of Olinia usambarensis. Here, we evaluated the inhibitory effects of these compounds on lipopolysaccharide (LPS)-induced production of nitric oxide (NO) and prostaglandin E2 (PGE2) in RAW 264.7 macrophages, and found that CDMP is the most potent of these two pro-inflammatory mediators (IC50; 12.12 µM and 10.78 µM, respectively). Consistent with these results, CDMP also down-regulated inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), tumor necrosis factor α (TNF-α), interleukin 1ß (IL-1ß), and interleukin 6 (IL-6) at the protein and mRNA levels in LPS-treated RAW 264.7 macrophages. Furthermore, CDMP suppressed LPS-induced nuclear factor κB (NF-κB) activation by decreasing p65 nuclear translocation through the phosphorylation and degradation of the inhibitory κBα (IκBα). CDMP also attenuated LPS-induced transcriptional and DNA-binding activities of activator protein 1 (AP-1) by suppressing the phosphorylation and expression of c-Fos and c-Jun. Finally, CDMP considerably suppressed the LPS-induced phosphorylation of c-Jun N-terminal kinase (JNK), but did not affect the phosphorylation of p38 or extracellular signal-regulated kinase (ERK). Taken together, our data suggest that CDMP down-regulates genes encoding pro-inflammatory mediators and cytokines, such as iNOS, COX-2, TNF-α, IL-1ß, and IL-6 via NF-κB and JNK/AP-1 inactivation in LPS-induced RAW 264.7 macrophages.


Subject(s)
Inflammation Mediators/metabolism , Myrtales/chemistry , NF-kappa B/antagonists & inhibitors , Pyrans/pharmacology , Signal Transduction/drug effects , Transcription Factor AP-1/antagonists & inhibitors , Animals , Cell Survival/drug effects , Cyclooxygenase 2/metabolism , Cytokines/genetics , Cytokines/metabolism , Extracellular Signal-Regulated MAP Kinases/metabolism , Lipopolysaccharides/pharmacology , Mice , Myrtales/metabolism , NF-kappa B/metabolism , Nitric Oxide/metabolism , Nitric Oxide Synthase Type II/metabolism , Plant Leaves/chemistry , Plant Leaves/metabolism , Pyrans/chemistry , RAW 264.7 Cells , Transcription Factor AP-1/metabolism
11.
Arch Pharm Res ; 42(9): 766-772, 2019 Sep.
Article in English | MEDLINE | ID: mdl-30721453

ABSTRACT

Phytochemical investigation on the 70% aqueous EtOH extract from the roots of Patrinia scabra led to the isolation and characterization of five new non-glycosidic iridoids, patriscabrins F-J (1-5), along with a known iridoid 11-ethoxyviburtinal (6). The structures of the new compounds 1-5 were determined by interpretation of spectroscopic data, particularly by 1D- and 2D-NMR and ECD studies. Thereafter, the isolates 1-6 were evaluated for their inhibitory effects on lipopolysaccharide-induced nitric oxide production in RAW 264.7 cells. Of these, patriscabrin F (1) exhibited the most potent inhibitory effect with observed IC50 value of 14.1 µM. In addition, patriscabrin G (2) and 11-ethoxyviburtinal (6) showed IC50 values 24.6 and 35.5 µM, respectively.


Subject(s)
Iridoids/pharmacology , Nitric Oxide/biosynthesis , Patrinia/chemistry , Plant Roots/chemistry , Animals , Density Functional Theory , Dose-Response Relationship, Drug , Iridoids/chemistry , Iridoids/isolation & purification , Lipopolysaccharides/antagonists & inhibitors , Lipopolysaccharides/pharmacology , Mice , Molecular Structure , RAW 264.7 Cells , Structure-Activity Relationship
12.
Molecules ; 23(10)2018 Oct 07.
Article in English | MEDLINE | ID: mdl-30301280

ABSTRACT

This article describes the design, synthesis, and in vitro anti-inflammatory screening of new triarylpyrazole derivatives. A total of 34 new compounds were synthesized containing a terminal arylsulfonamide moiety and a different linker between the sulfonamide and pyridine ring at position 4 of the pyrazole ring. All the target compounds were tested for both cytotoxicity and nitric oxide (NO) production inhibition in lipopolysaccharide (LPS)-induced RAW 264.7 macrophages. Compounds 1b, 1d, 1g, 2a, and 2c showed the highest NO inhibition percentages and the lowest cytotoxic effect. The most potent derivatives were tested for their ability to inhibit prostaglandin E2 (PGE2) in LPS-induced RAW 264.7 macrophages. The IC50 for nitric oxide inhibition, PGE2 inhibition, and cell viability were determined. In addition, 1b, 1d, 1g, 2a, and 2c were tested for their inhibitory effect on LPS-induced inducible nitric oxide synthase (iNOS) and Cyclooxygenase 2 (COX-2) protein expression as well as iNOS enzymatic activity.


Subject(s)
Dinoprostone/chemistry , Macrophages/chemistry , Nitric Oxide/chemistry , Pyrazoles/chemical synthesis , Animals , Cyclooxygenase 2/genetics , Dinoprostone/antagonists & inhibitors , Gene Expression Regulation, Enzymologic/drug effects , Lipopolysaccharides/toxicity , Macrophages/drug effects , Mice , Nitric Oxide/antagonists & inhibitors , Nitric Oxide Synthase Type II/genetics , Pyrazoles/chemistry , Pyrazoles/pharmacology , RAW 264.7 Cells , Sulfonamides/chemical synthesis , Sulfonamides/chemistry , Sulfonamides/pharmacology
13.
J Nat Prod ; 81(6): 1468-1473, 2018 06 22.
Article in English | MEDLINE | ID: mdl-29799195

ABSTRACT

An activity-guided fractionation procedure of the 70% aqueous EtOH extract from the roots of Patrinia scabra led to the isolation and characterization of five new iridoids, patriscabrins A-E (1-5), along with 13 known compounds. The structures of 1-5 were determined by interpretation of spectroscopic data, particularly by 1D and 2D NMR, ECD, and VCD studies. Thereafter, isolates were evaluated for their inhibitory effects on lipopolysaccharide-induced nitric oxide production in RAW 264.7 cells. Of these, the new iridoids 2 and 5 and the known lignan patrineolignan B (6) exhibited IC50 values of 14.7 to 17.8 µM.


Subject(s)
Iridoids/chemistry , Iridoids/pharmacology , Lipopolysaccharides/pharmacology , Nitric Oxide/metabolism , Patrinia/chemistry , Plant Roots/chemistry , Animals , Cell Line , Lignans/metabolism , Macrophages/drug effects , Macrophages/metabolism , Magnetic Resonance Spectroscopy/methods , Mice , RAW 264.7 Cells
14.
ACS Macro Lett ; 7(6): 651-655, 2018 Jun 19.
Article in English | MEDLINE | ID: mdl-35632972

ABSTRACT

Microporous organic polymer nanoparticles bearing tetraphenylethylene moieties (MOPTs) were prepared in the presence of poly(vinylpyrrolidone) (PVP). The PVP was entrapped into the microporous network of MOPT to form MOPT-P and played the roles of size control, porosity enhancement, and surface property management. MOPT materials without PVP showed superhydrophobicity with a water contact angle of 151°. In comparison, the MOPT-P showed excellent water compatibility. Moreover, due to the aggregation-induced emission property of tetraphenylethylene moieties, the MOPT-P showed emission and excellent emission-based sensing of nitrophenols in water with Ksv values in the range of 1.26 × 104 ∼ 3.37 × 104 M-1. It is noteworthy that the MOPT-P used water only as a sensing medium and did not require additional organic solvents to enhance water dispersibility of materials. The MOPT-P could be recovered and reused for the sensing at least five times.

15.
Biotechnol J ; 11(5): 633-41, 2016 May.
Article in English | MEDLINE | ID: mdl-26762773

ABSTRACT

Vectors flanked by regulatory DNA elements have been used to generate stable cell lines with high productivity and transgene stability; however, regulatory elements in Chinese hamster ovary (CHO) cells, which are the most widely used mammalian cells in biopharmaceutical production, are still poorly understood. We isolated a novel gene regulatory element from CHO-K1 cells, designated E77, which was found to enhance the stable expression of a transgene. A genomic library was constructed by combining CHO-K1 genomic DNA fragments with a CMV promoter-driven GFP expression vector, and the E77 element was isolated by screening. The incorporation of the E77 regulatory element resulted in the generation of an increased number of clones with high expression, thereby enhancing the expression level of the transgene in the stable transfectant cell pool. Interestingly, the E77 element was found to consist of two distinct fragments derived from different locations in the CHO genome shotgun sequence. High and stable transgene expression was obtained in transfected CHO cells by combining these fragments. Additionally, the function of E77 was found to be dependent on its site of insertion and specific orientation in the vector construct. Our findings demonstrate that stable gene expression mediated by the CMV promoter in CHO cells may be improved by the isolated novel gene regulatory element E77 identified in the present study.


Subject(s)
Gene Expression , Genetic Engineering/methods , Regulatory Sequences, Nucleic Acid , Transgenes , Animals , CHO Cells , Cloning, Molecular , Cricetinae , Cricetulus , Genome , Genomic Library , Promoter Regions, Genetic
16.
ACS Macro Lett ; 5(12): 1322-1326, 2016 Dec 20.
Article in English | MEDLINE | ID: mdl-35651200

ABSTRACT

The reactor fouling is a notorious obstacle in managing continuous synthetic processes of polyketones. The fouling raises synthetic costs and reduces the bulk density of polymers. Thus, efficient seed materials are required for antifouling performance. Hollow microporous organic polymers (HMOPs) were prepared using ZIF-8 nanoparticles as templating materials. Sulfonic groups were incorporated into HMOP via a post synthetic approach. The resultant HMOP-SO3H (20-90 µg/mL in methanol) showed successful catalyst activation and antifouling performance in polyketone synthesis.

17.
Appl Microbiol Biotechnol ; 99(23): 10117-26, 2015 Dec.
Article in English | MEDLINE | ID: mdl-26245680

ABSTRACT

Gene amplification using dihydrofolate reductase gene (dhfr) and methotrexate (MTX) is widely used for recombinant protein production in mammalian cells and is typically conducted in DHFR-deficient Chinese hamster ovary (CHO) cell lines. Generation of DHFR-deficient cells can be achieved by an expression vector incorporating short hairpin RNA (shRNA) that targets the 3'-untranslated region (UTR) of endogenous dhfr. Thus, shRNAs were designed to target the 3'-UTR of endogenous dhfr, and shRNA-2 efficiently down-regulated dhfr expression in CHO-K1 cells. A single gene copy of shRNA-2 also decreased the translational level of DHFR by 80% in Flp-In CHO cells. shRNA-2 was then incorporated into a plasmid vector expressing human erythropoietin (EPO) and an exogenous DHFR to develop EPO-producing cells in the Flp-In system. The specific EPO productivity (q EPO) was enhanced by stepwise increments of MTX concentration, and differences in the amplification rate were observed in Flp-In CHO cells that expressed shRNA-2. In addition, the q EPO increased by more than 2.5-fold in the presence of 500 nM MTX. The mRNA expression level and gene copy numbers of dhfr were correlated with increased productivity in the cells, which is influenced by inhibition of endogenous dhfr. This study reveals that an expression vector including shRNA that targets the 3'-UTR of endogenous dhfr can enhance the transgene amplification rate and productivity by generating DHFR-deficient cells. This approach may be applied for amplifying the foreign gene in wild-type cell lines as a versatile single-plasmid vector.


Subject(s)
3' Untranslated Regions , Erythropoietin/biosynthesis , Gene Knockdown Techniques/methods , RNA, Small Interfering/genetics , Tetrahydrofolate Dehydrogenase/genetics , Transgenes , Animals , CHO Cells , Cricetulus , Erythropoietin/genetics , Genetic Vectors , Humans , Methotrexate/metabolism , Plasmids , RNA, Small Interfering/metabolism , Tetrahydrofolate Dehydrogenase/metabolism , Transcriptional Activation/drug effects , Up-Regulation
18.
Korean J Med Educ ; 21(1): 77-8, 2009 Mar.
Article in English | MEDLINE | ID: mdl-25812961
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