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1.
Viruses ; 16(5)2024 05 18.
Article in English | MEDLINE | ID: mdl-38793686

ABSTRACT

Parrot bornavirus (PaBV) is an infectious disease linked with proventricular dilatation disease (PDD) with severe digestive and neurological symptoms affecting psittacine birds. Despite its detection in 2008, PaBV prevalence in Taiwan remains unexplored. Taiwan is one of the leading psittacine bird breeders; hence, understanding the distribution of PaBV aids preventive measures in controlling spread, early disease recognition, epidemiology, and transmission dynamics. Here, we aimed to detect the prevalence rate of PaBV and assess its genetic variation in Taiwan. Among 124 psittacine birds tested, fifty-seven were PaBV-positive, a prevalence rate of 45.97%. Most of the PaBV infections were adult psittacine birds, with five birds surviving the infection, resulting in a low survival rate (8.77%). A year of parrot bornavirus surveillance presented a seasonal pattern, with peak PaBV infection rates occurring in the spring season (68%) and the least in the summer season (25%), indicating the occurrence of PaBV infections linked to seasonal factors. Histopathology reveals severe meningoencephalitis in the cerebellum and dilated cardiomyopathy of the heart in psittacine birds who suffered from PDD. Three brain samples underwent X/P gene sequencing, revealing PaBV-2 and PaBV-4 viral genotypes through phylogenetic analyses. This underscores the necessity for ongoing PaBV surveillance and further investigation into its pathophysiology and transmission routes.


Subject(s)
Bird Diseases , Bornaviridae , Mononegavirales Infections , Phylogeny , Psittaciformes , Animals , Taiwan/epidemiology , Bornaviridae/genetics , Bornaviridae/classification , Bornaviridae/isolation & purification , Mononegavirales Infections/veterinary , Mononegavirales Infections/virology , Mononegavirales Infections/epidemiology , Bird Diseases/virology , Bird Diseases/epidemiology , Prevalence , Psittaciformes/virology , Seasons , Genetic Variation , Parrots/virology , Epidemiological Monitoring/veterinary
2.
Front Bioeng Biotechnol ; 12: 1363742, 2024.
Article in English | MEDLINE | ID: mdl-38558788

ABSTRACT

In recent years, stem cells and their secretomes, notably exosomes, have received considerable attention in biomedical applications. Exosomes are cellular secretomes used for intercellular communication. They perform the function of intercellular messengers by facilitating the transport of proteins, lipids, nucleic acids, and therapeutic substances. Their biocompatibility, minimal immunogenicity, targetability, stability, and engineerable characteristics have additionally led to their application as drug delivery vehicles. The therapeutic efficacy of exosomes can be improved through surface modification employing functional molecules, including aptamers, antibodies, and peptides. Given their potential as targeted delivery vehicles to enhance the efficiency of treatment while minimizing adverse effects, exosomes exhibit considerable promise. Stem cells are considered advantageous sources of exosomes due to their distinctive characteristics, including regenerative and self-renewal capabilities, which make them well-suited for transplantation into injured tissues, hence promoting tissue regeneration. However, there are notable obstacles that need to be addressed, including immune rejection and ethical problems. Exosomes produced from stem cells have been thoroughly studied as a cell-free strategy that avoids many of the difficulties involved with cell-based therapy for tissue regeneration and cancer treatment. This review provides an in-depth summary and analysis of the existing knowledge regarding exosomes, including their engineering and cardiovascular disease (CVD) treatment applications.

3.
Ecotoxicol Environ Saf ; 272: 116065, 2024 Mar 01.
Article in English | MEDLINE | ID: mdl-38330872

ABSTRACT

Bisphenol A (BPA) and its substitute bisphenol S (BPS) are desirable materials widely used in manufacturing plastic products but can pose carcinogenic risks to humans. A new conductive iron-based metal-organic framework (Fe-HHTP)-modified pencil graphite electrode (PGE) for electrochemically sensing BPA and BPS was prepared and fully characterized by SEM, TEM, FT-IR, XRD, and XPS. Results showed that the optimal conditions for preparing Fe-HHTP/PGE were a pH of 6.5, a Fe-HHTP concentration of 2 mg·mL-1, a deposition potential of 0 V, and a deposition time of 100 s. The Fe-HHTP/PGE prepared under such conditions harbored a significant electrocatalytic activity with a detection limit of 0.8 nM for BPA and 1.7 nM for BPS (S/N = 3). Correspondingly, the electrochemical response current was linearly correlated to BPA and BPS, ranging from 0.01 to 100 µM. Fe-HHTP/PGE also obtained satisfactory recoveries by 93.8-102.1% and 96.0-101.3% for detecting BPA and BPS in plastic food packaging samples. Our work has provided a novel electrochemical tool to simultaneously detect BPA and BPS in food packaging samples and environmental matrixes.


Subject(s)
Graphite , Metal-Organic Frameworks , Phenols , Humans , Graphite/chemistry , Spectroscopy, Fourier Transform Infrared , Benzhydryl Compounds/chemistry , Electrodes
4.
J Org Chem ; 88(24): 17322-17329, 2023 Dec 15.
Article in English | MEDLINE | ID: mdl-38044560

ABSTRACT

A visible-light-induced annulation/thiolation of 2-isocyanobiaryls with dialkyl(aryl)disulfides has been established, delivering a sustainable and atom-economic route to 6-organoylthiophenanthridines with wild functional group tolerance and good to excellent yields under oxidant-, base-, and transition-metal-free conditions.

5.
Sci Rep ; 13(1): 19409, 2023 11 08.
Article in English | MEDLINE | ID: mdl-37938596

ABSTRACT

This study aimed to assess the feasibility of using magnetic resonance imaging (MRI)-based Delta radiomics characteristics extrapolated from the Ax LAVA + C series to identify intermediary- and high-risk factors in patients with cervical cancer undergoing surgery following neoadjuvant chemoradiotherapy. A total of 157 patients were divided into two groups: those without any intermediary- or high-risk factors and those with one intermediary-risk factor (negative group; n = 75). Those with any high-risk factor or more than one intermediary-risk factor (positive group; n = 82). Radiomics characteristics were extracted using Ax-LAVA + C MRI sequences. The data was divided into training (n = 126) and test (n = 31) sets in an 8:2 ratio. The training set data features were selected using the Mann-Whitney U test and the Least Absolute Shrinkage and Selection Operator (LASSO) test. The best radiomics features were then analyzed to build a preoperative predictive radiomics model for predicting intermediary- and high-risk factors in cervical cancer. Three models-the clinical model, the radiomics model, and the combined clinic and radiomics model-were developed in this study utilizing the random forest Algorithm. The receiver operating characteristic (ROC) curve, decision curve analysis (DCA), accuracy, sensitivity, and specificity were used to assess the predictive efficacy and clinical benefits of each model. Three models were developed in this study to predict intermediary- and high-risk variables associated with postoperative pathology for patients who underwent surgery after receiving neoadjuvant radiation. In the training and test sets, the AUC values assessed using the clinical model, radiomics model, and combined clinical and radiomics models were 0.76 and 0.70, 0.88 and 0.86, and 0.91 and 0.89, respectively. The use of machine learning algorithms to analyze Delta Ax LAVA + C MRI radiomics features can aid in the prediction of intermediary- and high-risk factors in patients with cervical cancer receiving neoadjuvant therapy.


Subject(s)
Neoadjuvant Therapy , Uterine Cervical Neoplasms , Humans , Female , Uterine Cervical Neoplasms/diagnostic imaging , Uterine Cervical Neoplasms/therapy , Algorithms , Ambulatory Care Facilities , Risk Factors
6.
Viruses ; 15(10)2023 10 20.
Article in English | MEDLINE | ID: mdl-37896905

ABSTRACT

Domestic cat hepadnavirus (DCH) is an infectious disease associated with chronic hepatitis in cats, which suggests a similarity with hepatitis B virus infections in humans. Since its first identification in Australia in 2018, DCH has been reported in several countries with varying prevalence rates, but its presence in Taiwan has yet to be investigated. In this study, we aimed to identify the presence and genetic diversity of DCH infections in Taiwan. Among the 71 samples tested, eight (11.27%) were positive for DCH. Of these positive cases, three cats had elevated levels of alanine transaminase (ALT) and aspartate transaminase (AST), suggesting an association between DCH infection and chronic hepatitis. Four DCH-positive samples were also tested for feline immunodeficiency virus (FIV) and feline leukemia virus (FeLV) coinfection. One sample (25%) was positive for FIV, whereas there was no positive sample for FeLV (0%). In addition, we performed whole genome sequencing on six samples to determine the viral genome sequences. Phylogenetic analyses identified a distinct lineage compared with previously reported sequences. This study highlights the importance of continuous surveillance of DCH and further research to elucidate the pathophysiology and transmission route of DCH.


Subject(s)
Cat Diseases , Hepadnaviridae , Immunodeficiency Virus, Feline , Humans , Animals , Cats , Hepadnaviridae/genetics , Phylogeny , Taiwan/epidemiology , Immunodeficiency Virus, Feline/genetics , Leukemia Virus, Feline , Hepatitis, Chronic , Genetic Variation , Cat Diseases/epidemiology
7.
J Org Chem ; 88(13): 8360-8368, 2023 Jul 07.
Article in English | MEDLINE | ID: mdl-37262353

ABSTRACT

A 1,2,3,5-tetrakis(carbazol-9-yl)-4,6-dicyanobenzene (4-CzIPN)-photocatalyzed cascade arylation/cyclization reaction of 2-isocyanobiaryls and iodonium ylides was established for the synthesis of 6-arylated phenanthridines. This is the first example of employing iodonium ylides as aryl radical sources in a visible-light-induced radical cascade cyclization reaction.


Subject(s)
Light , Phenanthridines , Cyclization
8.
J Org Chem ; 88(4): 2288-2295, 2023 Feb 17.
Article in English | MEDLINE | ID: mdl-36738288

ABSTRACT

A simple and practical electron donor-acceptor (EDA) strategy to synthesize various 3-alkylated coumarins from easily available coumarins and naturally abundant carboxylic acids under photocatalyst-, oxidant-, and additive-free and mild conditions is reported. Using Na2S as the catalytic electron donor, a series of primary, secondary, and tertiary carbon radicals can be efficiently generated, and the EDA complex can be regenerated without an alkaline additive.

9.
Org Biomol Chem ; 20(43): 8501-8505, 2022 Nov 09.
Article in English | MEDLINE | ID: mdl-36268850

ABSTRACT

The first example of the electrocatalytic multicomponent synthesis of 4-chloro/bromo/iodopyrazoles from hydrazines, acetylacetones and sodium halides under chemical oxidant- and external electrolyte-free conditions has been developed. Sodium halides played a dual role as a halogenation reagent and a supporting electrolyte. Mechanism studies revealed that the bromination reaction proceeded via an ionic pathway, whereas both chlorination and iodination proceeded via a radical pathway.


Subject(s)
Halogens , Sodium , Halogenation , Oxidants , Ions
10.
Biosensors (Basel) ; 12(6)2022 May 27.
Article in English | MEDLINE | ID: mdl-35735515

ABSTRACT

The electronic conductive metal-organic frameworks (EC-MOFs) based on a single ligand are not suitable for the accurate detection of bisphenol A (BPA) due to the limitations of their electron-transfer-based sensing mechanism. To overcome this drawback, we developed EC-MOFs with novel dual-ligands, 2,3,6,7,10,11-hexahydroxy-sanya-phenyl (HHTP) and tetrahydroxy 1,4-quinone (THQ), and metal ions. A new class of 2D π-conjugation-based EC-MOFs (M-(HHTP)(THQ)) was synthesized by a self-assemble technique. Its best member (Cu-(HHTP)(THQ)) was selected and combined with reduced graphene (rGO) to form a Cu-(HHTP)(THQ)@rGO composite, which was thoroughly characterized by X-ray diffraction, field scanning electron microscopy, and energy-dispersive X-ray spectroscopy. Cu-(HHTP)(THQ)@rGO was drop-cast onto a glassy carbon electrode (GCE) to obtain a sensor for BPA detection. Cyclic voltammetry and electrochemical impedance tests were used to evaluate the electrode performance. The oxidation current of BPA on the Cu-(HHTP)(THQ)@rGO/GCE was substantially higher than on unmodified GCE, which could be explained by a synergy between Cu-(HHTP)(THQ) (which provided sensing and adsorption) and rGO (which provided fast electron conductivity and high surface area). Cu-(HHTP)(THQ)@rGO/GCE exhibited a linear detection range for 0.05-100 µmol·L-1 of BPA with 3.6 nmol·L-1 (S/N = 3) detection limit. We believe that our novel electrode and BPA sensing method extends the application perspectives of EC-MOFs in the electrocatalysis and sensing fields.


Subject(s)
Graphite , Metal-Organic Frameworks , Benzhydryl Compounds , Carbon/chemistry , Electrochemical Techniques/methods , Electrodes , Electronics , Graphite/chemistry , Ligands , Metal-Organic Frameworks/chemistry , Phenols
11.
BMJ Open ; 11(6): e045564, 2021 06 28.
Article in English | MEDLINE | ID: mdl-34183340

ABSTRACT

PURPOSE: The Westlake BioBank for Chinese (WBBC) pilot cohort is a population-based prospective study with its major purpose to better understand the effect of genetic and environmental factors on growth and development from adolescents to adults. PARTICIPANTS: A total of 14 726 participants (4751 males and 9975 females) aged 14-25 years were recruited and the baseline survey was carried out from 2017 to 2019. The pilot cohort contains rich range of information regarding of demographics and anthropometric measurements, lifestyle and sleep patterns, clinical and health outcomes. Visit the WBBC website for more information (https://wbbc.westlake.edu.cn/index.html). FINDINGS TO DATE: The mean age of the study samples were 18.6 years for males and 18.5 years for females, respectively. The mean height and weight were 172.9 cm and 65.81 kg for males, and 160.1 cm and 52.85 kg for females. Results indicated that the prevalence of underweight in female was much higher than male, but the prevalence of overweight and obesity in female was lower than male. The mean serum 25(OH)D level in the 14 726 young participants was 22.4±5.3 ng/mL, and male had a higher level of serum 25(OH)D than female, overall, 33.5% of the participants had vitamin D deficiency and even more participants suffered from vitamin D insufficiency (58.2%). The proportion of deficiency in females was much higher than that in males (41.8 vs 16.4%). The issue of underweight and vitamin D deficiency in young people should be paid attention, especially in females. These results reflected the fact that thinness and paler skin are preferred in modern aesthetics of Chinese culture. FUTURE PLANS: WBBC pilot is designed as a prospective cohort study and provides a unique and rich data set analysing health trajectories from adolescents to young adults. WBBC will continue to collect samples with old age.


Subject(s)
Biological Specimen Banks , Vitamin D Deficiency , Adolescent , Body Mass Index , China/epidemiology , Cohort Studies , Cross-Sectional Studies , Female , Humans , Male , Pilot Projects , Prevalence , Prospective Studies , Vitamin D , Young Adult
12.
Organogenesis ; 16(4): 113-125, 2020 10 01.
Article in English | MEDLINE | ID: mdl-32799735

ABSTRACT

Bone defects or fractures generally heal in the absence of major interventions due to the high regenerative capacity of bone tissue. However, in situations of severe/large bone defects, these orchestrated regeneration mechanisms are impaired. With advances in modern medicine, natural and synthetic bio-scaffolds from bioceramics and polymers that support bone growth have emerged and gained intense research interest. In particular, scaffolds that recapitulate the molecular cues of extracellular signals, particularly growth factors, offer potential as therapeutic bone biomaterials. The current challenges for these therapies include the ability to engineer materials that mimic the biological and mechanical properties of the real bone tissue matrix, whilst simultaneously supporting bone vascularization. In this review, we discuss the very recent innovative strategies in bone biomaterial technology, including those of endogenous biomaterials and cell/drug delivery systems that promote bone regeneration. We present our understanding of their current value and efficacy, and the future perspectives for bone regenerative medicine.


Subject(s)
Biocompatible Materials , Bone Regeneration , Bone and Bones/physiology , Tissue Engineering/methods , Tissue Scaffolds , Biomimetics , Ceramics/therapeutic use , Drug Delivery Systems , Extracellular Matrix , Humans , Mesenchymal Stem Cells/physiology , Polymers/therapeutic use , Regenerative Medicine
13.
Mol Med Rep ; 21(4): 1881-1889, 2020 04.
Article in English | MEDLINE | ID: mdl-32319611

ABSTRACT

Osteoarthritis (OA) is one of the most prevalent joint disorders globally. Patients suffering from OA are often obese and adiposity is linked to chronic inflammation. In the present study, the potential of using exosomes isolated from adipose­derived stem cells (ADSCs) as a therapeutic tool for reducing chronic inflammation and promoting chondrogenesis was investigated using patient­derived primary cells. First, it was tested whether patient­derived ADSCs could differentiate into chondrogenic and osteogenic lineages. The ADSCs were then used as a source of exosomes. It was found that exosomes isolated from ADSCs, when co­cultured with activated synovial fibroblasts, downregulated the expression of pro­inflammatory markers interleukin (IL)­6, NF­κB and tumor necrosis factor­α, while they upregulated the expression of the anti­inflammatory cytokine IL­10; without exosomes, the opposite observations were made. In addition, inflammation­inflicted oxidative stress was induced in vitro by stimulating chondrocytes with H2O2. Treatment with exosomes protected articular chondrocytes from H2O2­induced apoptosis. Furthermore, exosome treatment promoted chondrogenesis in periosteal cells and increased chondrogenic markers, including Collagen type II and ß­catenin; inhibition of Wnt/ß­catenin, using the antagonist ICG­001, prevented exosome­induced chondrogenesis. Periosteal cells treated with exosomes exhibited higher levels of microRNA (miR)­145 and miR­221. The upregulation of miR­145 and miR­221 was associated with the enhanced proliferation of periosteal cells and chondrogenic potential, respectively. The present study provided evidence in support for the use of patient­derived exosomes, produced from ADSCs, for potential chondrogenic regeneration and subsequent amelioration of osteoarthritis.


Subject(s)
Adipose Tissue/cytology , Chondrogenesis , Exosomes/metabolism , Inflammation/pathology , Mesenchymal Stem Cells/metabolism , MicroRNAs/genetics , Up-Regulation , Aged , Cell Differentiation , Cell Movement , Chondrocytes/metabolism , Fibroblasts/metabolism , Humans , Macrophages/metabolism , Male , MicroRNAs/metabolism , Middle Aged , Synovial Membrane/metabolism , Up-Regulation/genetics
14.
Org Lett ; 22(6): 2206-2209, 2020 Mar 20.
Article in English | MEDLINE | ID: mdl-32124611

ABSTRACT

A catalyst-, oxidant-, electrolyte-free method for the preparation of α-ketoamides through the direct electrochemical amidation of α-ketoaldehydes and amines with innocuous hydrogen as the sole byproduct at ambient temperature was developed. The present reaction features clean and mild conditions, excellent functional-group tolerance, and high atom economy and scalability, enabling facile applications in pharmaceutical chemistry.

15.
J Chemother ; 32(2): 53-65, 2020 Apr.
Article in English | MEDLINE | ID: mdl-31928332

ABSTRACT

Plants and natural compounds have been widely recognized to have potential for the prevention of cancer progression and as complementary or standalone treatments for cancer patients. The major benefits of natural compounds are their reduced toxicity compared to more aggressive and widely utilized cancer treatment approaches. Preclinical studies have led to the discovery of a number of natural anticancer compounds, including preparations of Vitex negundo L., green tea, mandarin peel oil, ursolic acid, curcumin and resveratrol. Although the in vitro data highlights the potential of these natural alternatives, their benefits in clinical cancer treatment remain less conclusive. In this review, we will discuss some of the recent advances in natural anticancer treatment discovery for the four most prominent global cancers, namely, breast, lung, prostate and skin metastases. As the exploration of natural therapeutics continues to expand, these substances have the potential to be utilized as preventative strategies and complimentary therapeutics. In some cases, they may have sufficient anti-tumor and anti-carcinogenic properties to function as standalone cancer treatments.


Subject(s)
Antineoplastic Agents, Phytogenic/pharmacology , Antineoplastic Agents, Phytogenic/therapeutic use , Neoplasms/drug therapy , Apoptosis/drug effects , Breast Neoplasms/drug therapy , DNA Methylation/drug effects , Humans , Inflammation Mediators/metabolism , Lung Neoplasms/drug therapy , Male , Membrane Potential, Mitochondrial/drug effects , Oxidative Stress/drug effects , Plant Extracts , Prostatic Neoplasms/drug therapy , Skin Neoplasms/drug therapy
16.
Biotechnol Lett ; 42(1): 1-10, 2020 Jan.
Article in English | MEDLINE | ID: mdl-31602549

ABSTRACT

Microcarriers are 100- to 300-micron support matrices that permit the growth of adherent cells in bioreactor systems. They have a larger surface area to volume ratio in comparison to single cell monolayers, enabling cost-effective cell production and expansion. Microcarriers are composed of a solid matrix that must be separated from expanded cells during downstream processing stages. The detachment method is chosen on the basis of several factors like cell type, microcarrier surface chemistry, cell confluency and degree of aggregation. The development of microcarriers with a range of physiochemical properties permit controlled cell and protein associations that hold utility for novel therapeutics. In this review, we provide an overview of the recent advances in microcarrier cell culture technology. We also discuss its significance as an ex vivo research tool and the therapeutic potential of newly designed microcarrier systems in vivo.


Subject(s)
Biotechnology/methods , Cell Culture Techniques/methods , Microspheres , Bioreactors , Biotechnology/trends , Cell Culture Techniques/trends
17.
Hum Genet ; 138(11-12): 1217-1225, 2019 Dec.
Article in English | MEDLINE | ID: mdl-31606751

ABSTRACT

Pluripotent stem cell (PSC) cultures form an integral part of biomedical and medical research due to their capacity to rapidly proliferate and differentiate into hundreds of highly specialized cell types. This makes them a highly useful tool in exploring human physiology and disease. Genomic editing of PSC cultures is an essential method of attaining answers to basic physiological functions, developing in vitro models of human disease, and exploring potential therapeutic strategies and the identification of drug targets. Achieving reliable and efficient genomic editing is an important aspect of using large-scale PSC cultures. The CRISPR/Cas9 genomic editing tool has facilitated highly efficient gene knockout, gene correction, or gene modifications through the design and use of single-guide RNAs which are delivered to the target DNA via Cas9. CRISPR/Cas9 modification of PSCs has furthered the understanding of basic physiology and has been utilized to develop in vitro disease models, to test therapeutic strategies, and to facilitate regenerative or tissue repair approaches. In this review, we discuss the benefits of the CRISPR/Cas9 system in large-scale PSC cultures.


Subject(s)
CRISPR-Cas Systems , Gene Editing , Gene Knockout Techniques , Genomics/methods , Pluripotent Stem Cells/physiology , Humans , Pluripotent Stem Cells/cytology
18.
Virus Res ; 270: 197675, 2019 09.
Article in English | MEDLINE | ID: mdl-31351879

ABSTRACT

Administration of oncolytic viruses (OVs) is an emerging anticancer strategy that exploits the lytic nature of viral replication to enhance the killing of malignant cells. OVs can be used as tools to directly induce cancer cell death and to trigger local and/or systemic immune responses to metastatic cancer in vivo. The effectiveness of OV therapy was initially highlighted by the clinical use of the genetically modified herpes virus, talimogene laherparepvec, for melanoma therapy. A number of OVs are now being evaluated as potential treatments for cancer in clinical trials. In spite of being engineered to specifically target tumor cells, the safety and off-target effects of OV therapy are a concern. The potential safety concerns of OVs are highlighted by current clinical trial criteria, which exclude individuals harbouring other viral infections and people who are immunocompromised. Despite the potential for adverse effects, clinical trials to date revealed relatively minimal adverse immune-related effects, such as fever. With advances in our understanding of virus replication cycles, several novel OVs have emerged. Reverse genetic systems have facilitated the insertion of anticancer genes into a range of OVs to further enhance their tumor-killing capacity. In this review, we highlight the recent advances in OV therapy for a range of human cancers in in vitro and in in vivo animal studies. We further discuss the future of OVs as a therapeutic strategy for a range of life-threatening cancers.


Subject(s)
Neoplasms/therapy , Oncolytic Virotherapy/methods , Oncolytic Viruses/genetics , Animals , Clinical Trials as Topic , Disease Models, Animal , Humans , Melanoma/therapy , Oncolytic Virotherapy/adverse effects , Oncolytic Virotherapy/trends , Oncolytic Viruses/physiology , Reverse Genetics , Virus Replication
19.
J Org Chem ; 83(4): 2369-2375, 2018 02 16.
Article in English | MEDLINE | ID: mdl-29400062

ABSTRACT

An efficient oxidative aminooxyarylation of alkenes under a transition-metal-free condition was described. Under the reaction conditions, N-hydroxyphthalimide (NHPI) reacted readily with N-arylacrylamides to produce cyclic products via a radical C-H functionalization process, achieving both C-O and C-C bonds formation in one pot. This reaction provided a facile access to the valuable aminooxylated oxindoles. The benzylic and α-methylene C(sp3)-H bonds were also aminooxylated under the reaction conditions.


Subject(s)
Alkenes/chemistry , Indoles/chemical synthesis , Indoles/chemistry , Molecular Structure , Oxidation-Reduction , Oxindoles
20.
Asian Pac J Trop Med ; 8(9): 739-46, 2015 Sep.
Article in English | MEDLINE | ID: mdl-26433660

ABSTRACT

OBJECTIVE: To invest the differences among mesenchymal stem cells (MSCs) derived from different tissues and their impacts on clinical applications. METHODS: In this study, MSCs were isolated from adipose tissue (AD), umbilical cord tissue (UC), and menstrual blood (Men) and compared their biological characteristics in terms of proliferation capacity, passage capacity, colony formation, and surface markers were compared. RESULTS: The stem cells (SCs) obtained from different sources were all characterized as MSCs, but demonstrated some differences. Umbilical cord-derived MSCs (UCMSCs) were able to overcome density inhibition. The proliferation rate decreased in the order UCMSCs > MenSCs > ADSCs, while the colony-forming ability decreased in the order MenSCs > ADSCs > UCMSCs. Based on gene-expression data for MSCs from different sources within the same donor, 768 MenSC genes were found that were specifically upregulated or downregulated compared with bone marrow-derived MSCs and UCMSCs, most of which were involved in cell function-related pathways. In addition, MenSCs appeared to be superior in terms of immune inflammation, stress response, and neural differentiation potentials, but weaker in terms of osteogenic and chondrogenic differentiation capacities, compared with UCMSCs and bone marrow-derived MSCs. CONCLUSIONS: MenSCs have higher extraction efficiency, colony-forming ability, and long time passage capacity. Although the proliferation capacity is inferior to UCMSCs.

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