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1.
Macromol Res ; 31(2): 133-142, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36844252

RESUMO

Biomass-derived isosorbide (ISB) is a promising alternative to petroleum-based monomers in industrial plastics. In this study, ISB-based thermoplastic polyurethanes (ISB-TPUs) were prepared using ISB as a biomass chain extender, and the effects of the preparation route on the structural and physical properties of the resultant polymers were investigated. Prepolymer methods were more suitable for obtaining the desired molecular weights (MWs) and physical properties of ISB-TPUs than the one-shot method. The presence of the solvent and catalyst in the prepolymer step had significant effects on the structural and physical properties of the resultant polymer. Among several prepolymer conditions, the solvent- and catalyst-free methods were the most suitable for preparing commercial-level ISB-TPUs, with number- and weight-average MWs (M n and M w ) of 32,881 and 90,929 g mol-1, respectively, and a tensile modulus (E) and ultimate tensile strength (UTS) of 12.0 and 40.2 MPa, respectively. In comparison, the presence of a catalyst in the prepolymer step resulted in lower MWs and mechanical properties (81,033 g mol-1 and 18.3 MPa of M w and UTS, respectively). The co-existence of the catalyst/solvent led to a further decline in the properties of ISB-TPUs (26,506 and 10.0 MPa of M w and UTS, respectively). ISB-TPU prepared via the solvent- and catalyst-free methods exhibited remarkable elastic recovery when subjected to up to 1000% strain in mechanical cycling tests. Rheological characterization confirmed the thermo-reversible phase change (thermoplasticity) of the polymer. Supplementary Information: The online version contains supplementary material available at 10.1007/s13233-023-00125-w.

2.
Artigo em Inglês | MEDLINE | ID: mdl-35580017

RESUMO

A Gram-stain-positive coccus was isolated from the blood of a paediatric patient suffering from gastroenteritis. The taxonomic position of this catalase-positive, non-motile, non-spore-forming facultative anaerobe designated as strain MKL-02T was investigated using a polyphasic approach. Colonies grown on tryptic soy agar with 10 % sheep blood were circular, creamy yellow, and convex. Phylogenetic analysis based on 16S rRNA gene and whole-genome sequences revealed that this strain was most closely related to Arsenicicoccus bolidensis CCUG 47306T within the cluster of the genus Arsenicicoccus. Average nucleotide identity and digital DNA-DNA hybridization values between strain MKL-02T and A. bolidensis DSM 15745T, A. dermatophillus DSM 25571T and A. piscis DSM 22760T were 89.5 and 37.0 %, 79.6 and 22.4 %, and 75.9 and 21.0 %, respectively. The genomic size of strain MKL-02T was 3 423 857 bp with a 72.7 mol% G+C content. Growth was observed at 10-45 °C (optimum, 37-40 °C) and pH 6.0-10.0 (optimum, pH 7.0), in the presence of 0-10 % (w/v) NaCl (optimum, 0.5 %). Cells of strain MKL-02T were non-motile cocci and 0.50-0.60 µm long, as determined by transmission electron microscopy. The strain was catalase-positive and oxidase-negative. The major fatty acid type (>10 % of total) was C15 : 0. The polar lipid profile consisted of two unidentified phospholipids, three unidentified lipids and an unidentified aminophospholipid. The strain contained MK-8 (H4) as the predominant menaquinone. Based on phylogenetic and phenotypic considerations, it is proposed that strain MKL-02T be classified as a new species, named Arsenicicoccus cauae sp. nov. The type strain is MKL-02T (=NCCP 16967T=JCM 34624T).


Assuntos
Infecções por Actinomycetales , Actinomycetales , Gastroenterite , Actinomycetales/isolamento & purificação , Infecções por Actinomycetales/sangue , Infecções por Actinomycetales/microbiologia , Animais , Técnicas de Tipagem Bacteriana , Composição de Bases , Catalase/genética , Criança , DNA Bacteriano/genética , Ácidos Graxos/química , Gastroenterite/sangue , Gastroenterite/microbiologia , Humanos , Hibridização de Ácido Nucleico , Fosfolipídeos/química , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Ovinos
3.
Macromol Res ; 29(10): 720-726, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34754287

RESUMO

Although biodegradable plastics are gradually emerging as an effective solution to alleviate the burgeoning plastic pollution, their performance is currently trivial for commercialization. A proposed two-pronged strategy to overcome this limitation includes (1) preparation of the nanocomposites from biorenewable nano-fillers to preserve their biodegradability and (2) tailoring their properties to meet the diverse demands in various applications. Herein, we report the preparation of biodegradable nanocomposites composed of poly(butylene succinate) (PBS) and cellulose nanocrystals (CNCs) (loading of 0.2-3.0 wt%) and propose a rheological strategy to tailor their performances. Depending on the shear frequencies, the rheological evaluation revealed two percolation thresholds at approximately 0.8 and 1.5 wt%. At high shear frequencies, the disappearance of the first threshold (0.8 wt%) and the sole persistence of the second one (1.5 wt%) indicated the collapse of the immature network of partially interconnected CNCs. The tensile and hydrolytic properties of the nanocomposites were found to undergo drastic changes at the thresholds. The tensile strength increased by 17% (from 33.3 to 39.2 MPa) up to 0.8 wt% CNC loading. However, the reinforcing efficiency of CNC decreases sharply with further incorporation, reaching nearly zero at 1.5 wt%. On the other hand, hydrolytic degradation of the nanocomposites was rapidly accelerated above 1.5 wt% CNC loading. Therefore, a thorough understanding of the rheological properties of nanocomposites is essential for the design and development of materials with tailored properties.

4.
J Obstet Gynaecol Res ; 45(1): 69-77, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30230126

RESUMO

AIM: Group B streptococcus (GBS) is a leading cause of life-threatening bacterial infections among newborns, and neonates born to heavily colonized women may be subject to vertical transmission. We sought to determine an appropriate detection method for genital GBS in pregnant women by comparing culture-based methods and real-time polymerase chain reaction (PCR). In addition, we performed molecular serotyping and multilocus sequence typing (MLST) on isolates. METHODS: A total of 150 pregnant women were enrolled and underwent vaginal-rectal swabbing at 16-40 weeks of gestation. GBS was identified by conventional culture and real-time PCR with or without enrichment. Molecular serotyping and MLST were performed on isolates. RESULTS: Overall genital GBS positive rate among the 150 study subjects was 17.3%. Direct culture identified 18 (12.0%) positive specimens, enrichment culture 22 (14.6%), direct PCR 24 (16.0%) and enrichment PCR 25 (16.6%). The sensitivity and specificity by direct and enrichment PCR were as follows: for direct PCR, 90.9% and 96.9%, respectively; and for enrichment PCR, 95.5% and 96.9%, respectively. Resistance rates to clindamycin and erythromycin were 33.3% and 19.1%, respectively. Serotype III-1 was the most common (26.3%), followed by serotype Ib (21.1%), III-3 (15.8%), V (15.8%), II (10.5%), IV (5.3%) and VI (5.3%). Most common sequence types (ST) were ST-1, ST-19 and ST-862 (15.8%), followed by ST-2 and ST-654 (10.5%). CONCLUSION: Direct real-time PCR using vaginal-rectal specimen could be used for detecting GBS in emergent conditions. Molecular serotypes III, Ib and V were most common. MLST analysis frequently presented ST-1, ST-19 and ST-862.


Assuntos
Genoma Bacteriano , Genômica/métodos , Complicações Infecciosas na Gravidez/microbiologia , Sorogrupo , Infecções Estreptocócicas/microbiologia , Streptococcus/genética , Adulto , Feminino , Humanos , Tipagem de Sequências Multilocus/métodos , Gravidez , Complicações Infecciosas na Gravidez/epidemiologia , Reação em Cadeia da Polimerase em Tempo Real/métodos , República da Coreia/epidemiologia , Sorotipagem/métodos , Infecções Estreptocócicas/epidemiologia , Streptococcus/classificação
5.
Biochem Biophys Res Commun ; 493(2): 957-963, 2017 11 18.
Artigo em Inglês | MEDLINE | ID: mdl-28942141

RESUMO

Low dose of carbon monoxide (CO) has anti-inflammatory role through various signaling pathways. Cellular metabolism has been implicated in the activation of inflammation in immune cells. However, the mechanisms by which CO-dependent metabolic regulation affect the immune response remain unclear. Here we show that CO-dependent metabolic pathway regulates the activation of the nucleotide-binding domain, leucine-rich-repeat-containing receptor (NLR), pyrin-domain-containing 3 (NLRP3) inflammasome. CO-releasing molecule-3 (CORM-3) resulted in reduced glycolysis-dependent NLRP3 inflammasome activation in macrophages. The reduced mTORC1 activation by CORM-3 resulted in less glycolysis during NLRP3 inflammasome activation. CORM-3 suppressed caspase-1 activation and the secretion of interleukin (IL)-1ß and IL-18 in macrophages in response to lipopolysaccharide (LPS) and ATP. Moreover, CORM-3 inhibits the oligomerization of the adaptor protein apoptosis-associated speck-like protein containing a caspase recruitment domain (ASC), which is required for NLRP3-dependent caspase-1 activation. Furthermore, CORM-3-treated mice showed substantial reduction in IL-1ß production by hyperglycemia in a mouse model of streptozotocin (STZ)-induced diabetes. Our results suggest that CO regulates glycolysis-dependent NLRP3 inflammasome activation and may provide a therapeutic approach for inflammation in metabolic diseases.


Assuntos
Monóxido de Carbono/imunologia , Inflamassomos/imunologia , Macrófagos/imunologia , Proteína 3 que Contém Domínio de Pirina da Família NLR/imunologia , Animais , Glicólise/efeitos dos fármacos , Hiperglicemia/complicações , Hiperglicemia/tratamento farmacológico , Hiperglicemia/imunologia , Inflamação/tratamento farmacológico , Inflamação/imunologia , Macrófagos/efeitos dos fármacos , Masculino , Alvo Mecanístico do Complexo 1 de Rapamicina , Camundongos , Camundongos Endogâmicos C57BL , Complexos Multiproteicos/imunologia , Compostos Organometálicos/farmacologia , Compostos Organometálicos/uso terapêutico , Serina-Treonina Quinases TOR/imunologia
6.
J Clin Lab Anal ; 31(6)2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28177534

RESUMO

BACKGROUND: Clostridium difficile is a major pathogen responsible for nosocomial infectious diarrhea. We explored optimal laboratory strategies for diagnosis of C. difficile infection (CDI) in our clinical settings, a 1400-bed tertiary care hospital. METHODS: Using 191 fresh stool samples from adult patients, we evaluated the performance of Xpert C. difficile (Xpert CD), C. diff Quik Chek Complete (which simultaneously detects glutamate dehydrogenase [GDH] and C. difficile toxins [CDT]), toxigenic culture, and a two-step algorithm composed of GDH/CDT as a screening test and Xpert CD as a confirmatory test. RESULTS: Clostridium difficile was detected in 35 samples (18.3%), and all isolates were toxigenic strains. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value of each assay for detecting CDI were as follows: Quik Chek Complete CDT (45.7%, 100%, 100%, 89.1%), Quik Chek Complete GDH (97.1%, 99.4%, 97.1%, 99.4%), Xpert CD (94.3%, 100%, 100%, 98.7%), and toxigenic culture (91.4%, 100%, 100%, 98.1%). A two-step algorithm performed identically with Xpert CD assay. CONCLUSION: Our data showed that most C. difficile isolates from adult patients were toxigenic. We demonstrated that a two-step algorithm based on GDH/CDT assay followed by Xpert CD assay as a confirmatory test was rapid, reliable, and cost effective for diagnosis of CDI in an adult patient setting with high prevalence of toxigenic C. difficile.


Assuntos
Técnicas de Tipagem Bacteriana/métodos , Técnicas de Tipagem Bacteriana/estatística & dados numéricos , Infecções por Clostridium/diagnóstico , Idoso , Clostridioides difficile/isolamento & purificação , Fezes/microbiologia , Humanos , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Prospectivos
7.
J Clin Lab Anal ; 31(4)2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27660110

RESUMO

INTRODUCTION: The Mindray CAL 8000 is a cellular analysis line that consists of the BC-6800, an automated hematology analyzer, and the SC-120, an automated slidemaker/stainer. We evaluated the performances of the BC-6800 and the SC-120. METHODS: Four hundred and eight normal and abnormal samples were analyzed. The performance of the BC-6800 and Sysmex XE-2100 were compared, and blood films by the SC-120 and manual method were compared according to the CLSI guideline H26-A2 and H20-A2. RESULTS: Most parameters measured by the BC-6800 matched well with the XE-2100 and manual differential. The flag efficiency of the BC-6800 for blasts (95.3%) and atypical lymphocytes (92.6%) were higher while immature granulocytes (89.7%) and NRBCs (94.1%) were lower than that of the XE-2100. Additionally, the BC-6800 detected four of five samples infected with plasmodium parasites. The SC-120 showed no carry-over and expected repeatability. There was good agreement on the five-part differential including abnormal cells between blood films by the SC-120 and manually prepared blood films. The shape of the RBC was also comparable between blood films. CONCLUSION: The CAL-8000 analysis line is beneficial for precise, fast hematology work, and even more useful in malaria endemic areas.


Assuntos
Contagem de Células Sanguíneas/métodos , Contagem de Células Sanguíneas/normas , Coloração e Rotulagem/métodos , Coloração e Rotulagem/normas , Humanos , Modelos Lineares , Reprodutibilidade dos Testes
8.
J Med Virol ; 86(12): 2122-7, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24797344

RESUMO

Diagnostic tests for respiratory viral infections use traditionally either nasopharyngeal washes or swabs. Sputum is representative of the lower respiratory tract but is used rarely for viral testing. The aim of this study was to compare the detection rates of respiratory viruses from nasopharyngeal swabs and sputum using a multiplex real-time reverse transcription-polymerase chain reaction (RT-PCR). Adults who were admitted or presented to the clinics of Gil Medical Center with acute respiratory symptoms were recruited from 1 November 2012 to 31 March 2013. Paired specimens of nasopharyngeal swabs and sputum were obtained from 154 subjects, and RNA was extracted and tested for 16 different respiratory viruses using the Anyplex II RV16 Detection kit (Seegene, Seoul, Korea). The positive rate was 53% (81/154) for nasopharyngeal swabs and 68% (105/154) for sputum (P < 0.001). One hundred thirty-four viruses were identified for 107 illnesses. Influenza A virus, RSV A, HRV, coronavirus OC43, and adenovirus were detected more frequently in sputum samples than in nasopharyngeal swabs (P < 0.001). Importantly, 12 of 44 (27%) influenza A infections and 11 of 27 (41%) RSV infections were positive in only sputum samples. The detection rates of respiratory viruses from sputum samples were significantly higher than those from nasopharyngeal swabs in adults using real-time multiplex RT-PCR. These findings suggest that sputum would benefit for the detection of respiratory viruses by nucleic acid amplification tests (NAATs) in patients who produce sputum. Further studies are needed to establish standardized RNA extraction methods from sputum samples.


Assuntos
Técnicas de Laboratório Clínico/métodos , Reação em Cadeia da Polimerase Multiplex/métodos , Nasofaringe/virologia , Infecções Respiratórias/diagnóstico , Infecções Respiratórias/virologia , Escarro/virologia , Vírus/isolamento & purificação , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Sensibilidade e Especificidade , Virologia/métodos
9.
Platelets ; 24(5): 348-51, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-22738419

RESUMO

Changes of platelet count (PLT) and platelet parameters have been reported in iron deficiency anemia (IDA). However, the relationship between iron metabolism and thrombopoiesis is not yet fully known. We studied the relationship between iron and platelet parameters in women with IDA and thrombocytosis. Forty-one adult women with IDA and thrombocytosis were enrolled. The relationship between iron parameters (such as serum iron, serum ferritin, total iron-binding capacity (TIBC)C, and transferrin saturation (Tfsat)), and platelet parameters (PLT, platelet crit (PCT), mean platelet volume (MPV), mean platelet component (MPC), mean platelet mass, platelet distribution width, and large platelet (LPLT)), which measured with CBC on ADVIA, were investigated. In addition, the difference in platelet and iron parameters between severe IDA (Hb < 7 g/dl) and non-severe IDA were compared. PLT inversely correlated with serum iron and Tfsat (p < 0.05). Serum iron and TIBC revealed no significant relationships with any platelet parameters. PLT, PCT, and MPV inversely correlated with mean corpuscular hemoglobin concentration (MCHC) but MPC exhibited linear correlation with Hb, hematocrit, and MCHC (p < 0.05). PCT had linear correlation with PLT and MPV (p < 0.001), whereas PCT, MPV, and LPLT (p < 0.001 for two formers, p < 0.05) inversely correlated with MPC. In this study, the important iron parameters affecting PLT were serum iron and Tfsat. In addition, patients with more severe and hypochromic anemia had higher PLT, PCT, and MPV.


Assuntos
Anemia Ferropriva/metabolismo , Ferro/metabolismo , Contagem de Plaquetas , Trombocitose/metabolismo , Adulto , Idoso , Anemia Ferropriva/sangue , Anemia Ferropriva/etiologia , Índices de Eritrócitos , Feminino , Humanos , Ferro/sangue , Pessoa de Meia-Idade , Testes de Função Plaquetária , Trombocitose/sangue , Trombocitose/etiologia
10.
J Clin Lab Anal ; 26(5): 325-7, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23001976

RESUMO

Identification of rapidly growing mycobacteria (RGM) is problematic because there are many taxonomic changes. 16S rRNA gene is commonly used to identify Mycobacterium species, but alternative gene targets have been introduced for more accurate identification. We report a rare case of a prosthetic knee infection due to Mycobacterium wolinskyi. The isolate was not identified by 16S rRNA gene sequencing alone and substantially confirmed by rpoB gene sequencing. The identification was delayed because our laboratory did not routinely identify RGM to the species level. Simultaneous sequencing of both 16S rRNA and rpoB genes will allow rapid and accurate identification of M. wolinskyi isolates.


Assuntos
Genes Bacterianos/genética , Infecções por Mycobacterium/microbiologia , Mycobacterium/genética , Infecções Relacionadas à Prótese/microbiologia , Idoso , Antibacterianos/uso terapêutico , Proteínas de Bactérias/genética , Feminino , Humanos , Prótese do Joelho/microbiologia , Mycobacterium/isolamento & purificação , Infecções por Mycobacterium/diagnóstico , Infecções por Mycobacterium/tratamento farmacológico , Infecções Relacionadas à Prótese/diagnóstico , Infecções Relacionadas à Prótese/tratamento farmacológico , RNA Ribossômico 16S/genética
11.
Microsyst Nanoeng ; 8: 110, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36187890

RESUMO

The electrospraying of water in the cone-jet mode is difficult in practical applications owing to its low throughput and the electrical discharge caused by the high surface tension of water. A film with multiple dielectric micronozzles is essential for multiplexed electrospraying of water in cone-jet mode without electrical discharge. Thus, a pyramidal micronozzle film with five nozzles was fabricated using the UV-embossing process. The pyramidal micronozzle film consisted of pyramidal micronozzles, a micropillar array, and an in-plane extractor, which were proposed to minimize wetting and concentrate the electric field to the water meniscus at the tip of the pyramidal micronozzle. The electrospraying of water using a single pyramidal micronozzle was visualized by a high-speed camera at a flow rate of 0.15-0.50 ml/h with voltages of 0.0-2.3 kV, -1.6 kV, and -4.0 kV at the water, guide ring, and collector, respectively. Three distinct modes, the dripping, spindle, and cone-jet modes, were observed and distinguished according to the motion of the water meniscus at the nozzle tip. The steady Taylor cone and jet were observed in a voltage range of 1.3-2.0 kV in water, particularly in cone-jet mode. Multiplexed electrospraying of water in cone-jet mode at a flow rate of 1.5 ml/h was performed using a pyramidal micronozzle film, demonstrating the potential for a high-throughput electrospraying system.

12.
Biomedicines ; 10(2)2022 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-35203655

RESUMO

Patients with vascular dementia, caused by cerebral ischemia, experience long-term cognitive impairment due to the lack of effective treatment. The mechanisms of and treatments for vascular dementia have been investigated in various animal models; however, the insufficient information on gene expression changes that define pathological conditions hampers progress. To investigate the underlying mechanism of and facilitate treatment development for vascular dementia, we established a mouse model of chronic cerebral hypoperfusion, including bilateral carotid artery stenosis, by using microcoils, and elucidated the molecular pathway underlying vascular dementia development. Rho-associated protein kinase (ROCK) 1/2, which regulates cellular structure, and inflammatory cytokines (IL-1 and IL-6) were upregulated in the vascular dementia model. However, expression of claudin-5, which maintains the blood-brain barrier, and MAP2 as a nerve cell-specific factor, was decreased in the hippocampal region of the vascular dementia model. Thus, we revealed that ROCK pathway activation loosens the tight junction of the blood-brain barrier and increases the influx of inflammatory cytokines into the hippocampal region, leading to neuronal death and causing cognitive and emotional dysfunction. Our vascular dementia model allows effective study of the vascular dementia mechanism. Moreover, the ROCK pathway may be a target for vascular dementia treatment development in the future.

13.
Ann Lab Med ; 41(3): 323-327, 2021 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-33303718

RESUMO

Whole-genome sequencing (WGS) is an easily accessible and valuable tool in clinical microbiology, which can be used for identifying novel and rare species. We isolated gram-positive cocci from the blood of a pediatric patient, which could not be phenotypically identified using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) (BioMérieux, Marcy-l'Étoile, France). We could not identify the isolate to the species level using 16S ribosomal RNA (rRNA) sequencing. WGS was performed using the Illumina MiSeq platform (Illumina, San Diego, CA, USA); however, the subsequent genomic sequence database search using the TrueBac ID-Genome system (ChunLab, Inc., Seoul, Korea) did not yield any hits with an average nucleotide identity value >95.0%, which is the cut-off for species-level identification. Phylogenetic analysis suggested that the isolate belonged to a new Arsenicicoccus species, forming a subcluster with Arsenicicoccus bolidensis. Our data demonstrate that WGS allows a more accurate annotation of microbial genomes than other clinical microbiology tools, such as MALDI-TOF MS and 16S rRNA sequencing. This is the first report of the isolation of a novel Arsenicicoccus species from a clinical sample.


Assuntos
Actinobacteria/genética , Sequenciamento Completo do Genoma/métodos , Criança , Humanos , Filogenia , RNA Ribossômico 16S , República da Coreia , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
14.
Genes (Basel) ; 12(5)2021 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-33922649

RESUMO

(1) Background: The elevation of glucose metabolism is linked to high-grade gliomas such as glioblastoma multiforme (GBM). The high glycolytic phenotype is associated with cellular proliferation and resistance to treatment with chemotherapeutic agents in GBM. MicroRNA-542-3p (miR-542-3p) has been implicated in several tumors including gliomas. However, the role of miR-542-3p in glucose metabolism in human gliomas remains unclear; (2) Methods: We measured the levels of cellular proliferation in human glioma cells. We measured the glycolytic activity in miR-542-3p knockdown and over-expressed human glioma cells. We measured the levels of miR-542-3p and HK2 in glioma tissues from patients with low- and high-grade gliomas using imaging analysis; (3) Results: We show that knockdown of miR-542-3p significantly suppressed cellular proliferation in human glioma cells. Knockdown of miR-542-3p suppressed HK2-induced glycolytic activity in human glioma cells. Consistently, over-expression of miR-542-3p increased HK2-induced glycolytic activity in human glioma cells. The levels of miR-542-3p and HK2 were significantly elevated in glioma tissues of patients with high-grade gliomas relative to that in low-grade gliomas. The elevation of HK2 levels in patients with high-grade gliomas were positively correlated with the high levels of miR-542-3p in GBM and low-grade gliomas (LGG) based on the datasets from the Cancer Genome Atlas (TCGA) database. Moreover, the high levels of miR-542-3p were associated with poor survival rate in the TCGA database; (4) Conclusions: miR-542-3p contributes to the HK2-mediated high glycolytic phenotype in human glioma cells.


Assuntos
Biomarcadores Tumorais/genética , Neoplasias Encefálicas/genética , Glioma/genética , Glicólise , Hexoquinase/genética , MicroRNAs/genética , Biomarcadores Tumorais/metabolismo , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Proliferação de Células , Feminino , Glioma/metabolismo , Glioma/patologia , Hexoquinase/metabolismo , Humanos , Masculino , MicroRNAs/metabolismo , Pessoa de Meia-Idade
15.
Cells ; 9(5)2020 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-32357563

RESUMO

Human pluripotent stem cells (hPSCs), such as embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSCs), have a well-orchestrated program for differentiation and self-renewal. However, the structural features of unique proteostatic-maintaining mechanisms in hPSCs and their features, distinct from those of differentiated cells, in response to cellular stress remain unclear. We evaluated and compared the morphological features and stress response of hPSCs and fibroblasts. Compared to fibroblasts, electron microscopy showed simpler/fewer structures with fewer networks in the endoplasmic reticulum (ER) of hPSCs, as well as lower expression of ER-related genes according to meta-analysis. As hPSCs contain low levels of binding immunoglobulin protein (BiP), an ER chaperone, thapsigargin treatment sharply increased the gene expression of the unfolded protein response. Thus, hPSCs with decreased chaperone function reacted sensitively to ER stress and entered apoptosis faster than fibroblasts. Such ER stress-induced apoptotic processes were abolished by tauroursodeoxycholic acid, an ER-stress reliever. Hence, our results revealed that as PSCs have an underdeveloped structure and express fewer BiP chaperone proteins than somatic cells, they are more susceptible to ER stress-induced apoptosis in response to stress.


Assuntos
Estresse do Retículo Endoplasmático/fisiologia , Retículo Endoplasmático/metabolismo , Células-Tronco Pluripotentes/citologia , Apoptose/fisiologia , Proteínas Estimuladoras de Ligação a CCAAT/metabolismo , Morte Celular/fisiologia , Retículo Endoplasmático/fisiologia , Fibroblastos/metabolismo , Humanos , Células-Tronco Pluripotentes/metabolismo , Transdução de Sinais/fisiologia , Resposta a Proteínas não Dobradas/fisiologia
16.
Ann Lab Med ; 40(1): 7-14, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31432633

RESUMO

BACKGROUND: Rapid and accurate diagnosis of acute myocardial infarction (AMI) is critical for initiating effective treatment and achieving better prognosis. We investigated the performance of copeptin for early diagnosis of AMI, in comparison with creatine kinase myocardial band (CK-MB) and troponin I (TnI). METHODS: We prospectively enrolled 271 patients presenting with chest pain (within six hours of onset), suggestive of acute coronary syndrome, at an emergency department (ED). Serum CK-MB, TnI, and copeptin levels were measured. The diagnostic performance of CK-MB, TnI, and copeptin, alone and in combination, for AMI was assessed by ROC curve analysis by comparing the area under the curve (AUC). Sensitivity, specificity, negative predictive value, and positive predictive value of each marker were obtained, and the characteristics of each marker were analyzed. RESULTS: The patients were diagnosed as having ST elevation myocardial infarction (STEMI; N=43), non-ST elevation myocardial infarction (NSTEMI; N=25), unstable angina (N=78), or other diseases (N=125). AUC comparisons showed copeptin had significantly better diagnostic performance than TnI in patients with chest pain within two hours of onset (AMI: P=0.022, ≤1 hour; STEMI: P=0.017, ≤1 hour and P=0.010, ≤2 hours). In addition, TnI and copeptin in combination exhibited significantly better diagnostic performance than CK-MB plus TnI in AMI and STEMI patients. CONCLUSIONS: The combination of TnI and copeptin improves AMI diagnostic performance in patients with early-onset chest pain in an ED setting.


Assuntos
Glicopeptídeos/sangue , Infarto do Miocárdio/diagnóstico , Doença Aguda , Idoso , Angina Instável/diagnóstico , Área Sob a Curva , Creatina Quinase Forma MB/sangue , Diagnóstico Precoce , Serviço Hospitalar de Emergência , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio sem Supradesnível do Segmento ST/diagnóstico , Estudos Prospectivos , Curva ROC , Infarto do Miocárdio com Supradesnível do Segmento ST/diagnóstico , Troponina I/sangue
17.
Diabetes Metab J ; 43(5): 683-699, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31694081

RESUMO

BACKGROUND: Chronic inflammation has been linked to insulin resistance and type 2 diabetes mellitus (T2DM). High-fat diet (HFD)-derived fatty acid is associated with the activation of chronic inflammation in T2DM. PF-04620110, which is currently in phase 1 clinical trials as a selective acyl-CoA:diacylglycerol acyltransferase-1 (DGAT1) inhibitor, is a potent anti-diabetic agent that may be important for the regulation of chronic inflammation in T2DM. However, the mechanisms by which PF-04620110 regulates fatty acid-induced chronic inflammation remain unclear. METHODS: PF-04620110 was used in vitro and in vivo. DGAT1-targeting gRNAs were used for deletion of mouse DGAT1 via CRISPR ribonucleoprotein (RNP) system. The activation of NLRP3 inflammasome was measured by immunoblot or cytokine analysis in vitro and in vivo. RESULTS: Here we show that PF-04620110 suppressed fatty acid-induced nucleotide-binding domain, leucine-rich-repeat-containing receptor (NLR), pyrin-domain-containing 3 (NLRP3) inflammasome activation in macrophages. In contrast, PF-04620110 did not change the activation of the NLR family, CARD-domain-containing 4 (NLRC4), or the absent in melanoma 2 (AIM2) inflammasomes. Moreover, PF-04620110 inhibited K⁺ efflux and the NLRP3 inflammasome complex formation, which are required for NLRP3 inflammasome activation. PF-04620110 reduced the production of interleukin 1ß (IL-1ß) and IL-18 and blood glucose levels in the plasma of mice fed HFD. Furthermore, genetic inhibition of DGAT1 suppressed fatty acid-induced NLRP3 inflammasome activation. CONCLUSION: Our results suggest that PF-04620110 suppresses fatty acid-induced NLRP3 inflammasome activation.

18.
Sci Rep ; 9(1): 13325, 2019 09 16.
Artigo em Inglês | MEDLINE | ID: mdl-31527808

RESUMO

Hemoperfusion (HP) is one of the important treatment modalities in extracorporeal therapy for patients with acute intoxication. Its use has declined during the past 20 years despite its efficacy, because of its side effects, especially an increased risk of bleeding. Mechanisms of hemostasis impairment have not been clearly elucidated and studies demonstrating the mechanism are lacking. It is not clear which step of the hemostatic process is impaired during HP, and whether it leads to an increased risk of bleeding. We performed both in vivo and in vitro studies to elucidate the mechanism of impairment in the hemostatic process. In patients with acute pesticide intoxication who underwent HP, the platelet count decreased rapidly during the first 30 minutes from 242.4 ± 57.7 × 103/µL to 184.8 ± 49.6 × 103/µL, then gradually decreased even lower to 145.4 ± 61.2 × 103/µL over time (p < 0.001). As markers of platelet activation, platelet distribution width increased continuously during HP from 41.98 ± 9.28% to 47.69 ± 11.18% (p < 0.05), however, mean platelet volume did not show significant change. In scanning electron microscopy, activated platelets adhered to modified charcoal were observed, and delayed closure time after HP in PFA-100 test suggested platelet dysfunction occurred during HP. To confirm these conflicting results, changes of glycoprotein expression on the platelet surface were evaluated when platelets were exposed to modified charcoal in vitro. Platelet expression of CD61, fibrinogen receptor, significantly decreased from 95.2 ± 0.9% to 73.9 ± 1.6%, while those expressing CD42b, von Willebrand factor receptor, did not show significant change. However, platelet expression of CD49b, collagen receptor, significantly increased from 24.6 ± 0.7% to 51.9 ± 2.3%. Thrombin-antithrombin complex, a marker for thrombin generation, appeared to decrease, however, it was not statistically significant. Fibrin degradation products and d-dimers, markers for fibrinolysis, increased significantly during HP. Taken together, our data suggests that hemoperfusion leads to impairment of platelet aggregation with incomplete platelet activation, which was associated with reduced thrombin generation, accompanied by increased fibrinolysis.


Assuntos
Plaquetas/efeitos dos fármacos , Hemoperfusão/efeitos adversos , Praguicidas/toxicidade , Adulto , Idoso , Coagulação Sanguínea/efeitos dos fármacos , Plaquetas/metabolismo , Feminino , Fibrinólise/efeitos dos fármacos , Hemoperfusão/métodos , Hemorragia/metabolismo , Hemostasia/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade , Praguicidas/intoxicação , Ativação Plaquetária/efeitos dos fármacos , Ativação Plaquetária/fisiologia , Agregação Plaquetária/efeitos dos fármacos , Agregação Plaquetária/fisiologia , Trombina/metabolismo
19.
Cells ; 8(8)2019 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-31434287

RESUMO

Idiopathic pulmonary fibrosis (IPF) has been linked to chronic lung inflammation. Drosha ribonuclease III (DROSHA), a class 2 ribonuclease III enzyme, plays a key role in microRNA (miRNA) biogenesis. However, the mechanisms by which DROSHA affects the lung inflammation during idiopathic pulmonary fibrosis (IPF) remain unclear. Here, we demonstrate that DROSHA regulates the absent in melanoma 2 (AIM2) inflammasome activation during idiopathic pulmonary fibrosis (IPF). Both DROSHA and AIM2 protein expression were elevated in alveolar macrophages of patients with IPF. We also found that DROSHA and AIM2 protein expression were increased in alveolar macrophages of lung tissues in a mouse model of bleomycin-induced pulmonary fibrosis. DROSHA deficiency suppressed AIM2 inflammasome-dependent caspase-1 activation and interleukin (IL)-1ß and IL-18 secretion in primary mouse alveolar macrophages and bone marrow-derived macrophages (BMDMs). Transduction of microRNA (miRNA) increased the formation of the adaptor apoptosis-associated speck-like protein containing a caspase recruitment domain (ASC) specks, which is required for AIM2 inflammasome activation in BMDMs. Our results suggest that DROSHA promotes AIM2 inflammasome activation-dependent lung inflammation during IPF.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Fibrose Pulmonar Idiopática/patologia , Inflamassomos/metabolismo , Macrófagos Alveolares/metabolismo , Macrófagos/metabolismo , Pneumonia , Ribonuclease III/fisiologia , Adulto , Idoso , Animais , Células Cultivadas , Doença Crônica , Feminino , Humanos , Macrófagos/patologia , Macrófagos Alveolares/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Pessoa de Meia-Idade , Pneumonia/metabolismo , Pneumonia/patologia
20.
ACS Nano ; 13(11): 12500-12510, 2019 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-31584256

RESUMO

Stretchability and areal coverage of active devices are critical design considerations of stretchable or wearable photovoltaics and photodetections where high areal coverages are required. However, simultaneously maximizing both properties in conventional island-bridge structures through traditional two-dimensional manufacturing processes is difficult due to their inherent trade-offs. Here, a 3D printer-based strategy to achieve extreme system stretchability and high areal coverage through combining fused deposition modeling (FDM) and flexible conductive nanocomposites is reported. Distinguished from typical approaches of using conductive filaments for FDM which have a flexibility dilemma and conductivity trade-offs, the proposed axiomatic approach to embed a two-dimensional silver nanowire percolation network into the surfaces of flexible 3D printed structures offers sufficient conductivity and deformability as well as additional benefits of electrical junction enhancement and encapsulation of silver nanowires. Kirigami/origami-pattern-guided three-dimensional arrangements of encapsulated interconnections provide efficient control over stretchability and areal coverage. The suggested process enables a perovskite solar module with an initial areal coverage of ∼97% to be electrically and mechanically reversible with 400% system stretchability and 25 000% interconnect stretchability under the 1000 cycle test, by folding down or hiding the origami-applied interconnects under the islands. This 3D printing strategy of potentially low cost, large size capabilities, and high speed is promising for highly flexible future energy conversion applications.

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