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1.
Acta Radiol ; 62(5): 594-602, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-32551805

RESUMO

BACKGROUND: The coronary venous system is frequently used as an entry route to the heart and treatment modalities for many cardiac diseases and many procedures. Consequently, evaluation of the coronary venous system and understanding cardiac vein anatomy is crucial. PURPOSE: To determine the optimal image set in a comparison of noise-optimized linearly blended images (F_0.6) and noise-optimized virtual monoenergetic images (VMI+) evaluated by dual-energy computed tomography (DECT) for cardiac vein assessment. MATERIAL AND METHODS: Thirty-four patients (mean age 58.2 ± 14.2 years) who underwent DECT due to chest pain were enrolled. Images were post-processed with the F_0.6, and VMI+ algorithms at energy levels in the range of 40-100 keV in 10-keV increments. Enhancement (HU), noise, signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR) were objectively measured at two points in the great cardiac vein by consensus of two radiologists. Two blinded observers evaluated the subjective image quality of the great cardiac vein on a 4-point scale. RESULTS: HU, noise, and SNR peaked at 40 keV VMI+ (P < 0.05) among 50-100 keV VMI+. CNR peaked at 100 keV VMI+; however, there were no significant differences compared to CNR images processed at 40-90 keV VMI+. HU and noise were significantly higher in 40 keV VMI+ than F_0.6 images; however, both SNR and CNR were significantly higher in F_0.6 images. An assessment of subjective vein delineation revealed that F_0.6 images had the highest scores. CONCLUSION: F_0.6 images were superior to VMI+ and provided the optimal image set for cardiac vein assessment.


Assuntos
Vasos Coronários/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Imagem Radiográfica a Partir de Emissão de Duplo Fóton , Estudos Retrospectivos , Razão Sinal-Ruído , Adulto Jovem
2.
Materials (Basel) ; 13(19)2020 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-33022954

RESUMO

Concrete-filled tubular (CFT) columns have been widely used as structural members because CFT columns synergize the advantages of steel and concrete resulting in high strength, high ductility, and large energy dissipation capacity. Numerous studies have been performed to understand the behavior of CFT columns. However, the behavior of CFT columns remains uncertain due to their inelastic behavior and uncertain confinement effects, especially when failure occurs. In addition, diaphragms, which are generally installed, make it more complicated to understand the behavior of CFT columns. The purpose of this study is to investigate the effects of the diaphragms on the failure behavior of the CFT columns. To this end, eighteen rectangular CFT columns were tested with five different loading cases. The experimental results suggest that the size of the diaphragm has significant effects on the compressive strength and toughness of the CFT columns. In order to facilitate the proper composite actions of steel and concrete, the size of a diaphragm has to be at least three-quarters of the cross-sectional area.

3.
J Med Food ; 23(5): 523-534, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32119811

RESUMO

A variety of natural compounds have been used to reduce the oxidative stress associated with Alzheimer's disease, and many of these defend cells from oxidative stress-induced neuronal toxicity. In this study, the protective effect of radish (Raphanus raphanistrum) extract was investigated in mice and PC12 cells. In vivo behavioral tests were completed to examine the protective effects of the extract on amyloid beta (Aß)-peptide1-42-induced learning and memory impairment in a mouse model. The extract increased spontaneous alternation behaviors and step-through latency in mice. We discovered that administration of the extract reduced lipid peroxidation and Aß aggregation in a biochemical study of mice brain tissues. Treatment with the extract also increased acetylcholine and catalase activity in the brain. Furthermore, the radish extract attenuated H2O2-induced oxidative stress in cells. Through sequential fractionation of the radish extract, the active compound was identified as oleamide. These results suggest that the radish extract could have a protective role against oxidative stress-induced neuronal toxicity, possibly owing to the antioxidative activity of oleamide.


Assuntos
Antioxidantes/farmacologia , Encéfalo/efeitos dos fármacos , Transtornos da Memória/tratamento farmacológico , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/farmacologia , Raphanus/química , Peptídeos beta-Amiloides/metabolismo , Animais , Peróxido de Hidrogênio , Peroxidação de Lipídeos/efeitos dos fármacos , Camundongos , Fármacos Neuroprotetores/farmacologia , Células PC12 , Ratos
4.
Food Sci Biotechnol ; 27(4): 1193-1200, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30263850

RESUMO

Many edible plant extracts exhibit biological activities. For example, the ethanol extract of Pueraria montana var. lobata (P. montana) inhibits acetylcholinesterase (AChE), and red ginseng is well known for promoting health. In this study the authors investigated the synergistic effect of P. montana and red ginseng extracts on AChE activity in vitro and in mouse brain tissues and trimethyltin (TMT)-induced cognitive impairment in a mouse model of TMT-induced neurodegeneration. A diet containing a mixture of P. montana and red ginseng extracts reversed learning and memory impairments in Y-maze and passive avoidance behavioral tests. In addition, the mixture inhibited AChE activity and lipid peroxidation synergistically.

5.
Biol Pharm Bull ; 40(6): 932-935, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28566637

RESUMO

We previously reported that the extract of Cinnamomum loureirii (C. loureirii) significantly inhibited acetylcholinesterase (AChE), and identified 2,4-bis(1,1-dimethylethyl)phenol (BP) from C. loureirii as a potential AChE inhibitor. The present study, therefore was undertaken to demonstrate the effects of BP from C. loureirii on learning and memory impairment in trimethyltin (TMT)-treated ICR mice. Y-maze and passive avoidance tests were used to test cognitive ability. Further, changes in biochemical parameters in the brain tissue were also assessed in response to TMT injection and BP intervention. BP pre-administration (20, 40 mg/kg/d) in mice significantly protected cognitive dysfunction induced by TMT (p<0.05). Moreover, BP reduced AChE activity and lipid peroxidation but increased acetylcholine levels in the brain. In conclusion, we suggested that BP protected against TMT-induced cognitive dysfunction, and might be a potential agent for alleviating symptoms of neurodegenerative disorders, such as Alzheimer's disease, via modulating cholinergic functions.


Assuntos
Cinnamomum , Transtornos Cognitivos/tratamento farmacológico , Transtornos da Memória/tratamento farmacológico , Fármacos Neuroprotetores/uso terapêutico , Fenóis/uso terapêutico , Acetilcolinesterase/metabolismo , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Transtornos Cognitivos/induzido quimicamente , Transtornos Cognitivos/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Transtornos da Memória/induzido quimicamente , Transtornos da Memória/metabolismo , Camundongos Endogâmicos ICR , Fármacos Neuroprotetores/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Fenóis/farmacologia , Compostos de Trimetilestanho
6.
Cell Reprogram ; 18(4): 246-55, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27328332

RESUMO

Embryonic body-like colony formation is a unique pattern in male germ cell cultures, including spermatogonial stem cells. However, detailed information of the colony formation has not yet been sufficiently reported in male germ cell culture. To elucidate the formation of germ cell-derived colony (GDC), glial cell-derived neurotrophic factor receptor alpha-1 (GFRα-1)-positive pig germ cells were isolated using an immunomagnetic cell isolation method and labeled with red- or green-fluorescent dye. In GDC culture, red-fluorescent-labeled germ cells were evenly distributed in the wells from day 1 to 4, and they clustered together at the time of GDC formation on day 6. Interestingly, feeder cells migrated to the site of colony formation as spermatogonia carriers. Furthermore, when freshly prepared green-labeled GFRα-1-positive germ cells were added, mixed-fluorescent dye (red and green) colonies were observed. On bromodeoxyuridine (BrdU) treatment, 58% ± 3.13% of germ cells were positive to protein gene product 9.5 but negative to BrdU cells. Immunocytochemistry and reverse transcription-polymerase chain reaction results showed that cultured GDC cells were positive to stem cell- and pig germ cell-specific marker genes. In conclusion, in vitro formation of GDCs is mainly dependent on the aggregation of single germ cells as well as on the slow proliferation of germ cells.


Assuntos
Espermatogônias/fisiologia , Células-Tronco/fisiologia , Testículo/fisiologia , Animais , Animais Recém-Nascidos , Sobrevivência Celular , Células Cultivadas , Técnicas In Vitro , Masculino , Espermatogônias/citologia , Células-Tronco/citologia , Suínos , Testículo/citologia
7.
Stem Cells Int ; 2016: 6029271, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26880974

RESUMO

Enrichment of spermatogonial stem cells is important for studying their self-renewal and differentiation. Although germ cell-derived colonies (GDCs) have been successfully cultured from neonatal pig testicular cells under 31°C conditions, the short period of in vitro maintenance (<2 months) limited their application to further investigations. To develop a culture method that allows for in vitro maintenance of GDCs for long periods, we subcultured the GDCs with freshly prepared somatic cells from neonatal pig testes as feeder cells. The subcultured GDCs were maintained up to passage 13 with the fresh feeder cells (FFCs) and then frozen. Eight months later, the frozen GDCs could again form the colonies on FFCs as shown in passages 1 to 13. Immunocytochemistry data revealed that the FFCs expressed GATA-binding protein 4 (GATA4), which is also detected in the cells of neonatal testes and total testicular cells, and that the expression of GATA4 was decreased in used old feeder cells. The subcultured GDCs in each passage had germ and stem cell characteristics, and flow cytometric analyses revealed that ~60% of these cells were GFRα-1 positive. In conclusion, neonatal pig testes-derived GDCs can be maintained for long periods with GATA4-expressing testicular somatic cells.

8.
J Dermatol Sci ; 80(3): 186-95, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26481780

RESUMO

BACKGROUND: The phenotypic changes that accompany differentiation of resident fibroblasts into myofibroblasts are important aspects of the wound healing process. Recent studies showed that peroxisome proliferator-activated receptor (PPAR) δ plays a critical role in wound healing. OBJECTIVE: To determine whether the nuclear receptor PPARδ can modulate the differentiation of human dermal fibroblasts (HDFs) into myofibroblasts. METHODS: These studies were undertaken in primary HDFs using Western blot analyses, small interfering (si)RNA-mediated gene silencing, reporter gene assays, chromatin immunoprecipitation (ChIP), migration assays, collagen gel contraction assays, and real-time PCR. RESULTS: Activation of PPARδ by GW501516, a specific ligand of PPARδ, specifically upregulated the myofibroblast marker α-smooth muscle actin (α-SMA) in a time- and concentration-dependent manner. This induction was significantly inhibited by the presence of siRNA against PPARδ, indicating that PPARδ is involved in myofibroblast transdifferentiation of HDFs. Ligand-activated PPARδ increased α-SMA promoter activity in a dual mode by directly binding a direct repeat-1 (DR1) site in the α-SMA promoter, and by inducing expression of transforming growth factor (TGF)-ß, whose downstream effector Smad3 interacts with a Smad-binding element (SBE) in another region of the promoter. Mutations in these cis-elements totally abrogated transcriptional activation of the α-SMA gene by the PPARδ ligand; thus both sites represent novel types of PPARδ response elements. GW501516-activated PPARδ also increased the migration and contractile properties of HDFs, as demonstrated by Transwell and collagen lattice contraction assays, respectively. In addition, PPARδ-mediated upregulation of α-SMA was correlated with elevated expression of myofibroblast markers such as collagen I and fibronectin, with a concomitant reduction in expression of the epithelial marker E-cadherin. CONCLUSION: PPARδ plays pivotal roles in wound healing by promoting fibroblast-to-myofibroblast differentiation via TGF-ß/Smad3 signaling.


Assuntos
Actinas/metabolismo , Diferenciação Celular , PPAR delta/efeitos dos fármacos , PPAR delta/metabolismo , Tiazóis/farmacologia , Cicatrização , Actinas/genética , Caderinas/metabolismo , Movimento Celular , Células Cultivadas , Colágeno Tipo I/metabolismo , Fibroblastos , Fibronectinas/metabolismo , Humanos , Ligantes , PPAR delta/genética , Regiões Promotoras Genéticas , RNA Interferente Pequeno/farmacologia , Elementos de Resposta , Transdução de Sinais , Pele/citologia , Proteína Smad3/metabolismo , Ativação Transcricional , Fator de Crescimento Transformador beta/genética , Fator de Crescimento Transformador beta/metabolismo , Regulação para Cima/efeitos dos fármacos
9.
Lab Anim Res ; 31(3): 101-10, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26472962

RESUMO

To evaluate the hepatotoxicity and nephrotoxicity of Galla Rhois (GR) toward the liver and kidney of ICR mice, alterations in related markers including body weight, organ weight, urine composition, liver pathology and kidney pathology were analyzed after oral administration of 250, 500 and 1,000 mg/kg body weight/day of gallotannin-enriched extract of GR (GEGR) for 14 days. GEGR contained 68.7±2.5% of gallotannin, 25.3±0.9% of gallic acid and 4.4±0.1% of methyl gallate. Also, the level of malondialdehyde (MDA), a marker of lipid peroxidation, was decreased with 19% in the serum of high dose GEGR (HGEGR)-treated mice. The body and organ weight, clinical phenotypes, urine parameters and mice mortality did not differ among GEGR-treated groups and the vehicle-treated group. Furthermore, no significant increase was observed in alkaline phosphatase (ALP), alanine aminotransferase (ALT), aspartate aminotransferase (AST), lactate dehydrogenase (LDH), blood urea nitrogen (BUN) and the serum creatinine (Cr) in the GEGR-treated group relative to the vehicle-treated group. Moreover, the specific pathological features induced by most toxic compounds such as CCl4 were not observed upon liver and kidney histological analysis. Overall, the results of the present study suggest that GEGR does not induce any specific toxicity in liver and kidney organs of ICR at doses of 1,000 mg/kg body weight/day, indicating that this is no observed adverse effect level (NOAEL).

10.
Anim Sci J ; 86(4): 468-75, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25491717

RESUMO

To overcome shortages of human donor organs for organ failure patients, we made a commitment to develop gnotobiotic miniature swine as an alternative organ donor source for xenotransplantation. For this, we have constructed an absolute barrier-sustained gnotobiotic facility. Pregnant sows of gnotobiotic miniature swine, were procured and germfree piglets were obtained by hysterectomy. These were maintained in germfree isolators for about 4 weeks, deprived of colostrum and were fed sterilized soybean milk. They were associated with di-flora, anaerobic Lactobacillus sp. and Streptococcus sp. After confirmation of successful associations, gnotobiotic piglets were transferred into the facility aseptically. The piglets are maintained on high-efficiency particle air-filtered air in and out; maintaining constant room air pressure of 33 ± 3 mmAq, and sterile water and diet. In 10 sessions of hysterectomy, 18 male and 32 female piglets were obtained of which piglets (M six, F eight) died within 5 days. Among live piglets, piglets (M eight, F 12) were confirmed to be germfree by microbiological monitoring. For research of xenotransplantation, one consistent experimental result was essential. Therefore, major histocompatibility complex class II which related innate immunity, homozygotic gnotobiotic miniature swine was developed. As a result, genotyping revealed 14 individuals to be homozygous for major histocompatibility complex class II (DRB, DQB) as 0301, three individuals were homozygous as 0201 and each of two were homozygous for DQB as 0701 and DRB as 0404, respectively. Genetic modifications and immunological research for ideal alternative organ sources are in progress.


Assuntos
Vida Livre de Germes , Homozigoto , Complexo Principal de Histocompatibilidade/genética , Porco Miniatura/genética , Transplante Heterólogo , Animais , Feminino , Humanos , Gravidez , Suínos
11.
J Food Prot ; 74(3): 456-60, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21375884

RESUMO

In this study, three different selective media, modified cefoperazone charcoal deoxycholate agar (mCCDA), Karmali agar, and Preston agar, were compared for isolating Campylobacter jejuni from artificially contaminated ground beef and fresh-cut vegetables that have different levels of background microflora. Concurrently, an automated enzyme-linked immunosorbent assay method for detecting Campylobacter spp. (VIDAS Campylobacter) was evaluated by comparing it with the culture methods. Food samples inoculated with C. jejuni were enriched in Bolton broth at 42°C for 44 h and then streaked onto the three different selective media, followed by incubation under microaerobic conditions at 42°C for 48 h. The enriched Bolton broth (1 ml) was used in the VIDAS Campylobacter assay. No statistical differences in sensitivities were observed between the three selective media for ground beef and fresh-cut vegetables, but the selectivity of Preston agar was better (P < 0.05) than those of mCCDA and Karmali agar. The VIDAS Campylobacter assay showed a recovery rate similar (P > 0.05) to those of all of the medium combinations in ground beef. However, more positive samples (P < 0.05) were detected with the VIDAS Campylobacter than with the selective agars, except for the combinations of mCCDA plus Preston agar or mCCDA plus Karmali agar plus Preston agar in fresh-cut vegetables.


Assuntos
Campylobacter/isolamento & purificação , Meios de Cultura/química , Contaminação de Alimentos/análise , Produtos da Carne/microbiologia , Verduras/microbiologia , Animais , Bovinos , Qualidade de Produtos para o Consumidor , Microbiologia de Alimentos , Humanos , Sensibilidade e Especificidade
12.
Clin Auton Res ; 21(2): 103-10, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21057851

RESUMO

PURPOSE: The present study examined the relationships among cardiovascular autonomic, acoustic, and mood states in resting young subjects. METHODS: A total of 75 college students (men:women = 53:22), aged 19-24 years, were enrolled in this study. Each subject was asked to complete the profile of mood states and to produce a sustained vowel sound (/a/) for 3 s to calculate acoustic parameters. We calculated pulse rate variability (PRV) parameters such as low frequency (LF), high frequency (HF), total power (TP) and the ratio of low frequency to high frequency power (LF/HF) by analyzing peak-to-peak intervals detected by photoplethysmography. RESULTS: Sympathovagal balance-related parameters such as LF/HF were dominant indicators of fatigue in men and women, whereas LF and HF were indicative of depression and anger in women. In terms of acoustic parameters, shimmer and standard deviation of the fundamental frequency (SD F (0)), which were related to roughness and instability in voice quality, were indicative of tension and depression in men and women. CONCLUSIONS: The results of this study suggest that mood states in resting young subjects can be estimated from PRV and acoustic parameters.


Assuntos
Afeto/fisiologia , Sistema Nervoso Autônomo/fisiologia , Fenômenos Fisiológicos Cardiovasculares , Acústica da Fala , Voz/fisiologia , Feminino , Frequência Cardíaca/fisiologia , Humanos , Masculino , Pletismografia , Adulto Jovem
13.
Opt Express ; 17(21): 19047-54, 2009 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-20372640

RESUMO

An integral imaging system enabling extended depth of field was proposed and demonstrated based on a birefringence lens array (BLA) whose focal length was switched via the light polarization. The lens array system was constructed by combining two different liquid crystal(LC) embedded lens arrays, BLA I and II, which were fabricated by injecting a ZLI-4119 LC and an E-7 LC in between a lens array substrate and an ITO (indium-tin-oxide) glass plate respectively. The BLA I played a role as a convex lens only for the polarization parallel to the ordinary axis of the corresponding LC, but it serves as a plain medium for that along its extraordinary one since the refractive indexes of the lens and the LC are almost identical. Meanwhile, the BLA II played a role as a concave lens only for the polarization parallel to the extraordinary axis of the LC but as a plain medium for that along its ordinary one. As a result, the focal length could be switched via the polarization, and it was measured to be 680 mm and -29 mm. For the proposed system with the prepared BLAs, both real and virtual three-dimensional (3D) images were efficiently reconstructed at the positions of z=1300 mm and z=-30 mm with no significant degradation in the resolution, indicating its depth of field range.

14.
J Microbiol Biotechnol ; 18(3): 579-84, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18388480

RESUMO

A commercial chromogenic agar medium (DFI) was supplemented with glucose (mDFI) to enhance the specificity of Enterobacter sakazakii (E. sakazakii) detection. Escherichia vulneris (E. vulneris), a putative false-positive strain on the DFI medium, produces alpha-glucosidase. The enzyme alpha- glucosidase hydrolyzes a substrate, 5-bromo-4-chloro-3- indolyl-alpha,D-glucopyranoside (XalphaGlc), producing green colonies. E. sakazakii strains produced green colonies on both DFI and mDFI agar, whereas E. vulneris produced green colonies on DFI agar but small white colonies on mDFI agar. E. sakazakii and E. vulneris were also readily differentiated by colony color when the mixed culture of the two strains was plated on mDFI agar and incubated for 24 h at 37 degrees C. The results indicate that the selectivity of the commercial chromogenic agar medium could be improved by a simple supplementation with glucose.


Assuntos
Técnicas Bacteriológicas/métodos , Compostos Cromogênicos/metabolismo , Cronobacter sakazakii/citologia , Cronobacter sakazakii/isolamento & purificação , Meios de Cultura/química , Glucose/metabolismo , Cronobacter sakazakii/metabolismo , Escherichia/citologia , Escherichia/metabolismo , alfa-Glucosidases/metabolismo
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