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1.
Water Res ; 230: 119470, 2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36621274

RESUMO

Dissolved organic matter (DOM) in river watersheds dynamically changes based on its source during a monsoon period with storm event. However, the variations in DOM in urban and rural river watersheds that are dominated by point and non-point sources have not been adequately explored to date. We developed an innovative approach to reveal DOM sources in complex river watershed systems during pre-monsoon, monsoon, and post-monsoon periods using end-member mixing analysis (EMMA) by combining multi-isotope values (δ13C-DOC, δ15N-NO3 and δ18O-NO3) and spectroscopic indices (fluorescence index [FI], biological index [BIX], humification index [HIX], and specific UV absorbance [SUVA]). Several potential end-members of DOM sources were collected from watersheds, including top-soils, groundwater, plant group (fallen leaves, riparian plants, suspended algae), and different effluents (cattle and pig livestock, agricultural land, urban, industry facility, swine treatment facility and wastewater treatment facility). Concentrations of dissolved organic carbon, dissolved organic nitrogen, NO3-N, and NH4-N increased during the monsoon period with an increase in the input of anthropogenic DOM, which have higher HIX values owing to the flushing effect. The results of EMMA indicate that soil and agricultural effluents accounted for a substantial contribution of anthropogenic DOM at varying rates based on seasons. We also found that results of EMMA based on combining spectroscopic indices and δ13C-DOC isotope values were more accurate in tracing DOM sources with respect to land-use characteristics compared to applying only spectroscopic indices. The positive relationship between FI, BIX and δ15N-NO3 were revealed that nitrate would be decomposed from DOM affected by intensive agricultural activities. In addition, consistent with the EMMA results, the molecular composition of the DOM was clearly evidenced by a large number of CHON formulas, accounting for over 50% of the total characterized compounds, including pesticides and pharmaceuticals used in agriculture farmland and livestock. Our results clearly demonstrated that EMMA based on combing multi-stable isotopes and spectroscopic indices could be trace the DOM source, which is important for understanding changes in the DOM quality, and application of nitrate isotopes and molecular analysis supports in-depth interpretation. This study provides easy and intuitive techniques for the estimation of the relative impacts of DOM sources in complex river watersheds, which can be verified in various ways rather than relying on a single technique approach.


Assuntos
Matéria Orgânica Dissolvida , Rios , Animais , Bovinos , Suínos , Rios/química , Nitratos/análise , Análise Espectral , Solo , Compostos Orgânicos/análise , Isótopos/análise
2.
Sensors (Basel) ; 22(23)2022 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-36501999

RESUMO

In this study, we propose dynamic model update methods for the adaptive classification model of text streams in a distributed learning environment. In particular, we present two model update strategies: (1) the entire model update and (2) the partial model update. The former aims to maximize the model accuracy by periodically rebuilding the model based on the accumulated datasets including recent datasets. Its learning time incrementally increases as the datasets increase, but we alleviate the learning overhead by the distributed learning of the model. The latter fine-tunes the model only with a limited number of recent datasets, noting that the data streams are dependent on a recent event. Therefore, it accelerates the learning speed while maintaining a certain level of accuracy. To verify the proposed update strategies, we extensively apply them to not only fully trainable language models based on CNN, RNN, and Bi-LSTM, but also a pre-trained embedding model based on BERT. Through extensive experiments using two real tweet streaming datasets, we show that the entire model update improves the classification accuracy of the pre-trained offline model; the partial model update also improves it, which shows comparable accuracy with the entire model update, while significantly increasing the learning speed. We also validate the scalability of the proposed distributed learning architecture by showing that the model learning and inference time decrease as the number of worker nodes increases.


Assuntos
Idioma , Aprendizagem
4.
J Vasc Interv Radiol ; 32(1): 99-105, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33158669

RESUMO

PURPOSE: To evaluate efficacy and safety of transcatheter arterial embolization (TAE) in managing postpartum hemorrhage (PPH) due to genital tract injury after vaginal delivery and to investigate factors associated with outcome of TAE. MATERIALS AND METHODS: A retrospective review of 43 women (mean age, 32.6 years) who underwent TAE to manage PPH secondary to genital tract injury after vaginal delivery was performed at a single institution between January 2007 and December 2018. Clinical data and outcomes were obtained. Patients were classified into clinical success (n = 39) and failure (n = 4) groups, and comparisons between the groups were performed. RESULTS: The clinical success rate of TAE for PPH due to genital tract injury was 90.7%. In the clinical failure group, transfusion volumes were higher (failure vs success: packed red blood cells, 14 pt ± 3.37 vs 6.26 pt ± 4.52, P = .003; platelets, 10.33 pt ± 4.04 vs 2.92 pt ± 6.15, P = .036); hemoglobin levels before the procedure were lower (failure vs success: 7.3 g/dL vs 10.7, P = .016). Periprocedural complications included pulmonary edema (25.6%), fever (23.3%), and pain (9.3%). Twenty-four patients were either followed for > 6 months or answered a telephone survey; 23 (95.8%) recovered regular menstruation, and pregnancy was confirmed in 11 (45.8%). Regarding fertility desires, 7 women attempted to conceive, 6 of whom (85.7%) became pregnant. CONCLUSIONS: TAE is an effective and safe method for managing PPH due to genital tract injury after vaginal delivery. Lower hemoglobin levels before the procedure and higher transfusion volumes were associated with clinical failure of TAE.


Assuntos
Parto Obstétrico/efeitos adversos , Hemorragia Pós-Parto/terapia , Embolização da Artéria Uterina , Lesões do Sistema Vascular/terapia , Adulto , Biomarcadores/sangue , Transfusão de Sangue , Feminino , Hemoglobinas/metabolismo , Humanos , Hemorragia Pós-Parto/diagnóstico por imagem , Hemorragia Pós-Parto/etiologia , Gravidez , Estudos Retrospectivos , Fatores de Tempo , Resultado do Tratamento , Embolização da Artéria Uterina/efeitos adversos , Lesões do Sistema Vascular/diagnóstico por imagem , Lesões do Sistema Vascular/etiologia , Adulto Jovem
5.
Arch Craniofac Surg ; 21(3): 171-175, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32630989

RESUMO

BACKGROUND: Epidermoid cysts are benign tumors derived from the infundibular portion of hair follicles and thus have a flattened surface epithelium and keratohyaline granules. They can occur at any age but are most frequently reported in adults, and more often occur in men than women. Most epidermoid cyst operations are performed for cosmetic purposes, or to relieve inflammation. The definitive treatment is complete excision or destruction of the cyst. The aim of this study was to improve understanding of epidermoid cysts. METHODS: We analyzed 432 cases of epidermoid cyst in 398 patients that underwent complete excision and biopsy between April 2001 and March 2020, according to patient age, patient gender, and lesion location. RESULTS: From all epidermoid cyst excisions performed, 17.6% were for patients in their 40s and 50s, 16.8% for those in their 20s, 16.1% for those in their 30s, 14.6% for those aged 60 or older, 5.0% for teenagers, and 0.5% for those under 10 years. Cases of epidermoid cysts occurred at a men-to-women ratio of about 3:2, with 59.5% of cases in men and 40.5% in women. By lesion location, 65.0% of cases were on the face, 10.9% on the trunk, 7.9% on the scalp, 7.9% on the neck, 4.3% on lower extremities, 3.9% on upper extremities, and 0.2% on genitalia. On the face, 20.8% of cases were on the cheek, 12.7% on the periauricular area, 10.9% on the periorbital area, 6.0% on the frontal area, 5.6% on the mental area, 3.7% on the perioral area, 2.8% on the nasal area, and 2.5% on the temporal area. CONCLUSION: The proportion of women with epidermoid cysts was higher in our study than in previous studies. Moreover, the results showed that surgery has been on the rise in recent years, with facial surgery being the most common.

6.
J Microbiol ; 58(6): 519-529, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32462489

RESUMO

Adaptation to changing environmental conditions is crucial for the survival of microorganisms. Bacteria have evolved various mechanisms to cope with osmotic stress. Here, we report the identification and functional characterization of the osmotic stress response operon, betIBA, in Acinetobacter nosocomialis. The betIBA operon encodes enzymes that are important for the conversion of choline to the osmoprotectant, glycine betaine. The betIBA operon is polycistronic and is under the regulation of the first gene, betI, of the same operon. A bioinformatics analysis revealed the presence of a BetI-binding motif upstream of the betIBA operon, and electrophoretic mobility shift assays confirmed the specific binding of BetI. An mRNA expression analysis revealed that expression of betI, betB, and betA genes is elevated in a betI-eletion mutant compared with the wild type, confirming that the autorepressor BetI represses the betIBA operon in A. nosocomialis. We further found that the betIBA operon is under the transcriptional control of the quorum-sensing (QS) regulator, AnoR in, A. nosocomialis. A subsequent analysis of the impact of BetI on expression of the QS genes, anoR and anoI, demonstrated that BetI acts as a repressor of anoR and anoI. In addition, it was noticed that the osmotic stress response regulator, OmpR might play an important role in controlling the expression of betIBA operon in A. nosocomialis. Collectively, these data demonstrate that QS and osmotic stress-response systems are correlated in A. nosocomialis and that the expression of genes in both systems is finely tuned by various feedback loops depending on osmolarity conditions.


Assuntos
Acinetobacter/metabolismo , Proteínas de Bactérias/metabolismo , Óperon , Percepção de Quorum , Proteínas Repressoras/metabolismo , Acinetobacter/genética , Regulação Bacteriana da Expressão Gênica , Osmorregulação
7.
J Microbiol ; 58(6): 507-518, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32462488

RESUMO

Multidrug efflux pumps play an important role in antimicrobial resistance and pathogenicity in bacteria. Here, we report the functional characterization of the RND (resistance-nodulation- division) efflux pump, AcrAB, in Acinetobacter nosocomialis. An in silico analysis revealed that homologues of the AcrAB efflux pump, comprising AcrA and AcrB, are widely distributed among different bacterial species. Deletion of acrA and/or acrB genes led to decreased biofilm/pellicle formation and reduced antimicrobial resistance in A. nosocomialis. RNA sequencing and mRNA expression analyses showed that expression of acrA/B was downregulated in a quorum sensing (QS) regulator (anoR)-deletion mutant, indicating transcriptional activation of the acrAB operon by AnoR in A. nosocomialis. Bioassays showed that secretion of N-acyl homoserine lactones (AHLs) was unaffected in acrA and acrB deletion mutants; however, AHL secretion was limited in a deletion mutant of acrR, encoding the acrAB regulator, AcrR. An in silico analysis indicated the presence of AcrR-binding motifs in promoter regions of anoI (encoding AHL synthase) and anoR. Specific binding of AcrR was confirmed by electrophoretic mobility shift assays, which revealed that AcrR binds to positions -214 and -217 bp upstream of the translational start sites of anoI and anoR, respectively, demonstrating transcriptional regulation of these QS genes by AcrR. The current study further addresses the possibility that AcrAB is controlled by the osmotic stress regulator, OmpR, in A. nosocomialis. Our data demonstrate that the AcrAB efflux pump plays a crucial role in biofilm/pellicle formation and antimicrobial resistance in A. nosocomialis, and is under the transcriptional control of a number of regulators. In addition, the study emphasizes the interrelationship of QS and AcrAB efflux systems in A. nosocomialis.


Assuntos
Acinetobacter/fisiologia , Proteínas de Bactérias/fisiologia , Proteínas Associadas à Resistência a Múltiplos Medicamentos/fisiologia , Percepção de Quorum
8.
Genes Genomics ; 41(9): 1063-1075, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31177378

RESUMO

BACKGROUND: Acinetobacter has emerged recently as one of the most challenging nosocomial pathogens because of its increased rate of antimicrobial resistance. The genetic complexity and genome diversity, as well as the lack of adequate knowledge on the pathogenic determinants of Acinetobacter strains often hinder with pathogenesis studies for the development of better therapeutics to tackle this nosocomial pathogen. OBJECTIVES: In this study, we comparatively analyzed the whole genome sequence of a virulent Acinetobacternosocomialis strain NCTC 8102. METHODS: The genomic DNA of A. nosocomialis NCTC 8102 was isolated and sequenced using PacBio RS II platform. The sequenced genome was functionally annotated and gene prediction was carried out using the program, Glimmer 3. The phylogenetic analysis of the genome was performed using Mega 6 program and the comparative genome analysis was carried out by BLAST (Basic Local Alignment Search Tool). RESULTS: The complete genome analysis depicted that the genome consists of a circular chromosome with an average G + C content of 38.7%. The genome comprises 3700 protein-coding genes, 96 RNA genes (18 rRNA, 74 tRNA and 4 ncRNA genes), and 91 pseudogenes. In addition, 6 prophage regions comprising 2 intact, 1 incomplete and 3 questionable ones and 18 genomic islands were identified in the genome, suggesting the possible occurrence of horizontal gene transfer in this strain. Comparative genome analysis of A. nosocomialis NCTC 8102 genome with the already sequenced A. nosocomialis strain SSA3 showed an average nucleotide identity of 99.0%. In addition, the number of prophages and genomic islands were higher in the A. nosocomialis NCTC 8102 genome compared to that of the strain SSA3. 14 of the genomic islands were unique to A. nosocomialis NCTC 8102 compared to strain SSA3 and they harbored genes which are involved in virulence, multidrug resistance, biofilm formation and bacterial pathogenesis. CONCLUSION: We sequenced the whole genome of A. nosocomialis strain NCTC 8102 followed by comparatively genome analysis. The study provides valuable information on the genetic features of A. nosocomialis strain and the data from this study would assist in further studies for the development of control measures for this nosocomial pathogen.


Assuntos
Acinetobacter/genética , Genoma Bacteriano , Filogenia , Acinetobacter/classificação , Acinetobacter/patogenicidade , Biofilmes , Ilhas Genômicas , Anotação de Sequência Molecular , Prófagos/genética , Virulência/genética
9.
J Obstet Gynaecol Res ; 45(2): 299-305, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30288873

RESUMO

AIM: The present study investigates the procedure-related fetal loss rate and obstetrical outcomes of selective feticide in dichorionic twins. METHODS: We retrospectively analyzed the data of 44 cases of dichorionic twins. Two different indications for selective feticide were set: (i) the presence of genetic or congenital anomaly; and (ii) an obstetrical indication specified as a past maternal history of preterm delivery that caused fetal death or cerebral palsy of the child. Primarily, data on procedure-related fetal loss and obstetrical outcomes were retrieved. Additionally, data on obstetrical outcomes by reduction time and by indication of SF were obtained. RESULTS: Selective feticide was performed in 44 cases - specifically, in 23 cases with genetic or congenital anomaly and in 21 cases with obstetrical indications. The median gestational age at delivery was 38 + 4 weeks. One pregnancy loss (2.3%, 1/44) occurred within 4 weeks after the procedure. The overall pregnancy loss rate throughout the pregnancy term was 2.3% (1/44). When selective feticide was performed at 15 weeks and beyond, the birth weight was significantly decreased compared with when selective feticide was performed earlier than 15 weeks. CONCLUSION: Transabdominal ultrasound-guided selective feticide in dichorionic twins is an effective and safe procedure. If a patient desires to maximize her chances of having a healthy child and decrease the risk of prematurity, the option of selective feticide should be considered in certain cases of twin pregnancies. Selective feticide may be a reasonable alternative to expectant management or termination of the whole twin pregnancy.


Assuntos
Anormalidades Congênitas , Doenças Genéticas Inatas , Complicações na Gravidez , Resultado da Gravidez , Redução de Gravidez Multifetal/métodos , Gravidez de Gêmeos , Ultrassonografia Pré-Natal/métodos , Adulto , Anencefalia , Córion , Doenças em Gêmeos , Feminino , Doenças Fetais , Humanos , Gravidez , Complicações na Gravidez/prevenção & controle , Estudos Retrospectivos , Gêmeos Dizigóticos
10.
Dermatol Ther ; 31(5): e12695, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30156014

RESUMO

Lichen planus of the lip (LPL) is not common, and only a few cases have been reported. Medical treatment modalities for LPL are not always effective. Therefore, treatment of this presentation is difficult and challenging. A 41-year-old man was referred to the dermatology clinic with a chronic, painful erosion on the lower lip and buccal mucosa. Treatment with topical steroids, systemic cyclosporine, dapsone, and systemic steroids failed. We performed surgical excision and mucosal advancement flap treatment, with complete response noted after 6 months. Surgical excision with mucosal advancement flap treatment may be effective for the treatment of refractory LPL.


Assuntos
Líquen Plano/cirurgia , Doenças Labiais/cirurgia , Mucosa Bucal/cirurgia , Retalhos Cirúrgicos , Adulto , Doença Crônica , Humanos , Líquen Plano/tratamento farmacológico , Líquen Plano/patologia , Masculino , Retratamento
11.
Exp Mol Med ; 49(7): e361, 2017 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-28751784

RESUMO

Remyelination via the transplantation of oligodendrocyte precursor cells (OPCs) has been considered as a strategy to improve the locomotor deficits caused by traumatic spinal cord injury (SCI). To date, enormous efforts have been made to derive OPCs from human pluripotent stem cells (hPSCs), and significant progress in the transplantation of such cells in SCI animal models has been reported. The current methods generally require a long period of time (>2 months) to obtain transplantable OPCs, which hampers their clinical utility for patients with SCI. Here we demonstrate a rapid and efficient method to differentiate hPSCs into neural progenitors that retain the features of OPCs (referred to as OPC-like cells). We used cell sorting to select A2B5-positive cells from hPSC-derived neural rosettes and cultured the selected cells in the presence of signaling cues, including sonic hedgehog, PDGF and insulin-like growth factor-1. This method robustly generated neural cells positive for platelet-derived growth factor receptor-α (PDGFRα) and NG2 (~90%) after 4 weeks of differentiation. Behavioral tests revealed that the transplantation of the OPC-like cells into the spinal cords of rats with contusive SCI at the thoracic level significantly improved hindlimb locomotor function. Electrophysiological assessment revealed enhanced neural conduction through the injury site. Histological examination showed increased numbers of axon with myelination at the injury site and graft-derived myelin formation with no evidence of tumor formation. Our method provides a cell source from hPSCs that has the potential to recover motor function following SCI.


Assuntos
Diferenciação Celular , Células Precursoras de Oligodendrócitos/citologia , Células Precursoras de Oligodendrócitos/transplante , Células-Tronco Pluripotentes/citologia , Células-Tronco Pluripotentes/transplante , Traumatismos da Medula Espinal/cirurgia , Animais , Antígenos/metabolismo , Axônios/metabolismo , Escala de Avaliação Comportamental , Linhagem Celular , Células Cultivadas , Modelos Animais de Doenças , Membro Posterior , Humanos , Masculino , Bainha de Mielina/fisiologia , Proteoglicanas/metabolismo , Ratos , Ratos Sprague-Dawley , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/metabolismo , Fatores de Tempo
12.
Int J Mol Sci ; 17(7)2016 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-27447607

RESUMO

Alternative splicing (AS) is an important molecular mechanism by which single genes can generate multiple mRNA isoforms. We reported previously that, in Oryza sativa, the cyclophilin 19-4 (OsCYP19-4.1) transcript was significantly upregulated in response to cold stress, and that transgenic plants were cold tolerant. Here we show that, under cold stress, OsCYP19-4 produces eight transcript variants by intron retention and exon skipping, resulting in production of four distinct protein isoforms. The OsCYP19-4 AS isoforms exhibited different cellular localizations in the epidermal cells: in contrast to OsCYP19-4.1, the OsCYP19-4.2 and OsCYP19-4.3 proteins were primarily targeted to guard and subsidiary cells, whereas OsCYP19-4.5, which consists largely of an endoplasmic reticulum (ER) targeting signal, was co-localized with the RFP-BiP marker in the ER. In OsCYP19-4.2, the key residues of the PPIase domain are altered; consistent with this, recombinant OsCYP19-4.2 had significantly lower PPIase activity than OsCYP19-4.1 in vitro. Specific protein-protein interactions between OsCYP19-4.2/3 and AtRCN1 were verified in yeast two-hybrid (Y2H) and bimolecular fluoresence complementation (BiFC assays), although the OsCYP19-4 isoforms could not bind each other. Based on these results, we propose that two OsCYP19-4 AS isoforms, OsCYP19-4.2 and OsCYP19-4.3, play roles linking auxin transport and cold stress via interactions with RCN1.


Assuntos
Processamento Alternativo/genética , Aromatase/metabolismo , Resposta ao Choque Frio/genética , Oryza/genética , Peptidilprolil Isomerase/metabolismo , Isoformas de Proteínas/genética , Aromatase/genética , Sequência de Bases , Retículo Endoplasmático/metabolismo , Immunoblotting , Oryza/crescimento & desenvolvimento , Oryza/metabolismo , Peptidilprolil Isomerase/genética , Mapas de Interação de Proteínas , Isoformas de Proteínas/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Técnicas do Sistema de Duplo-Híbrido
13.
Korean J Anesthesiol ; 68(3): 274-80, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26045931

RESUMO

BACKGROUND: During general anesthesia, a heated breathing circuit (HBC) is used to replace the heat and moisture exchange function of the upper airway. One HBC uses an air dryer filter that employs silica gel (SG) as a desiccant. SG is capable of adsorbing many organic compounds. Therefore, we undertook an in vitro study of the adsorption of desflurane by SG filters. METHODS: An HBC was connected to an anesthesia machine, and a test lung was connected to the circuit. The test lung was mechanically ventilated with 2 or 4 L/min of fresh gas flow, with and without the air dryer filter. Desflurane was administered at a 6 vol% on the vaporizer dial setting. The experiment was repeated 15 times in each group. The end-tidal concentrations were measured during the experiments. The air dryer filter weights were measured before and after the experiments, and the times required to achieve the specific end-tidal desflurane concentrations were determined. RESULTS: Significant differences in the end-tidal concentrations of desflurane were observed between the control and filter groups (P < 0.001). The filter weights increased significantly after the experiments (P < 0.001). The times required to achieve the same end-tidal desflurane concentrations were different with the application of the air dryer filter (P < 0.001). CONCLUSIONS: The adsorption of desflurane with the use of an air dryer filter was verified in this in vitro study. Careful attention is needed when using air dryer gel filters during general anesthesia.

14.
PLoS One ; 7(7): e39715, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22911689

RESUMO

Homogeneous culture of neural precursor cells (NPCs) derived from human pluripotent stem cells (hPSCs) would provide a powerful tool for biomedical applications. However, previous efforts to expand mechanically dissected neural rosettes for cultivation of NPCs remain concerns regarding non-neural cell contamination. In addition, several attempts to purify NPCs using cell surface markers have not demonstrated the expansion capability of the sorted cells. In the present study, we show that polysialic acid-neural cell adhesion molecule (PSA-NCAM) is detected in neural rosette cells derived from hPSCs, and employ PSA-NCAM as a marker for purifying expandable primitive NPCs from the neural rosettes. PSA-NCAM-positive NPCs (termed hNPC(PSA-NCAM+)) were isolated from the heterogeneous cell population of mechanically harvested neural rosettes using magnetic-based cell sorting. The hNPC(PSA-NCAM+) extensively expressed neural markers such as Sox1, Sox2, Nestin, and Musashi-1 (80∼98% of the total cells) and were propagated for multiple passages while retaining their primitive characteristics in our culture condition. Interestingly, PSA-NCAM-negative cells largely exhibited characteristics of neural crest cells. The hNPC(PSA-NCAM+) showed multipotency and responsiveness to instructive cues towards region-specific neuronal subtypes in vitro. When transplanted into the rat striatum, hNPC(PSA-NCAM+) differentiated into neurons, astrocytes, and oligodendrocytes without particular signs of tumorigenesis. Furthermore, Ki67-positive proliferating cells and non-neural lineage cells were rarely detected in the grafts of hNPC(PSA-NCAM+) compared to those of neural rosette cells. Our results suggest that PSA-NCAM-mediated cell isolation provides a highly expandable population of pure primitive NPCs from hPSCs that will lend themselves as a promising strategy for drug screening and cell therapy for neurodegenerative disorders.


Assuntos
Células-Tronco Pluripotentes Induzidas/metabolismo , Moléculas de Adesão de Célula Nervosa/metabolismo , Células-Tronco Neurais/metabolismo , Ácidos Siálicos/metabolismo , Animais , Encéfalo/citologia , Técnicas de Cultura de Células , Diferenciação Celular , Proliferação de Células , Sobrevivência Celular , Células Cultivadas , Feminino , Humanos , Separação Imunomagnética , Células-Tronco Pluripotentes Induzidas/citologia , Células-Tronco Pluripotentes Induzidas/transplante , Células-Tronco Neurais/citologia , Células-Tronco Neurais/transplante , Neurônios/citologia , Neurônios/metabolismo , Ratos , Ratos Sprague-Dawley , Transplante de Células-Tronco
16.
Electrophoresis ; 31(18): 3053-60, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20725917

RESUMO

The development of a simple, sensitive, and direct method for the total analysis of certain endocrine disruptors was performed by integrating preconcentration steps to a separation step on a microchip through the modification of the field-amplified sample stacking and field-amplified sample injection steps. To improve the preconcentration and separation performances, the preconcentration and separation buffers were modified with citrate-stabilized gold nanoparticles (AuNPs). For the detection of the separated samples, cellulose-dsDNA/AuNPs-modified carbon paste electrodes were used at the channel end. The experimental parameters affecting the analytical performances, such as the buffer concentration, water plug length, SDS concentration in the separation buffer, AuNPs concentration, preconcentration time, detection potential and electrode to channel distance, were examined. The detection limits of the test compounds were between 7.1 and 11.1 fM and that for 4-pentylphenol was 7.1 (±1.1) fM. Dynamic ranges were in the range from 0.15 to 600.0 pM. The experiments with real samples were performed to evaluate the reliability of the proposed method.


Assuntos
Eletroforese em Microchip/métodos , Disruptores Endócrinos/análise , Ouro/química , Nanopartículas Metálicas/química , Fenóis/análise , Carbono/química , Celulose/química , DNA/química , Eletrodos , Modelos Lineares , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Temperatura , Água/química , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/isolamento & purificação
17.
Brain Dev ; 32(8): 658-68, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19854013

RESUMO

PURPOSE: We intended to determine whether transplanted neural precursors, derived from mouse embryonic stem (ES) cells, can migrate and differentiate into mature neurons and glial cells in damaged brains and improve functional deficits caused by global cerebral ischemic injury in adolescent rats. METHODS: Global ischemia was induced using the four-vessel occlusion method. ES cells that display enhanced expression of yellow fluorescent protein were co-cultured in N2 supplemented media with PA6 cells that had stromal derived inducing activity. Neural precursor cells were directly transplanted bilaterally into hippocampal C3 areas 2 weeks after induction of global ischemia. Assessments of the Morris water-maze test at eight weeks and, the Open field activity levels at two, four, six and eight weeks after transplantation were carried out according to standard methods. RESULTS: From neural precursors, we were able to generate neural lineages, including neurons and glial cells in vitro. Eight weeks following transplantation, cellular migration as well as generation of neural cells including neurons, astrocytes, and oligodendrocytes developed from the grafted ES cell-derived neural precursors were observed. Cell-transplanted animals exhibited enhanced functional recovery on sensorimotor and behavioral tests, compared to vehicle-treated control animals. CONCLUSION: Therefore, transplantation of mouse ES cell-derived neural precursor cells shows promise for improving recovery after global ischemia in adolescent rats.


Assuntos
Comportamento Animal/fisiologia , Isquemia Encefálica/reabilitação , Isquemia Encefálica/cirurgia , Células-Tronco Embrionárias/fisiologia , Transplante de Células-Tronco , Células-Tronco/fisiologia , Animais , Biomarcadores/metabolismo , Isquemia Encefálica/patologia , Isquemia Encefálica/fisiopatologia , Células Cultivadas , Técnicas de Cocultura , Células-Tronco Embrionárias/citologia , Corantes Fluorescentes/metabolismo , Masculino , Camundongos , Testes Neuropsicológicos , Ratos , Ratos Sprague-Dawley , Células-Tronco/citologia
18.
Exp Mol Med ; 38(5): 455-65, 2006 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-17079861

RESUMO

Gastric cancer is one of the most common cancers worldwide. The purpose of this study was to find out potential markers for gastric cancer. Tumor and normal tissues from 152 gastric cancer cases were analyzed by two-dimensional gel electrophoresis (2-DE). The images of silver stained gels were analyzed and statistical analysis of spot intensities revealed that spot 4262 showed higher expression (5.7-fold increase) in cancer tissues than in normal tissues (P < 0.001). It was identified by peptide mass fingerprinting as nicotinamide N-methyltransferase (NNMT). A monoclonal antibody with a detection limit down to 10 ng was produced against NNMT in mouse. Using the prepared monoclonal antibody, western blot analysis of NNMT was performed for gastric tissues from 15 gastric cancer patients and two gastric ulcer patients. The results corroborated those of 2-DE experiments. A single spot was detected in gastric ulcer tissues while four to five spots were detected in gastric cancer tissues. In cancer tissues, two additional spots of acidic and basic form were mainly detected on 2-DE gels. This suggests that NNMT receives a post-translational modification in cancer- specific manner.


Assuntos
Carcinoma/metabolismo , Nicotinamida N-Metiltransferase/metabolismo , Processamento de Proteína Pós-Traducional , Neoplasias Gástricas/metabolismo , Animais , Anticorpos Monoclonais/biossíntese , Biomarcadores Tumorais/isolamento & purificação , Western Blotting/métodos , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Nicotinamida N-Metiltransferase/imunologia , Fosforilação , Proteoma/análise , Úlcera Gástrica/metabolismo , Distribuição Tecidual
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