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1.
Eur Radiol ; 33(9): 6157-6167, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37095361

RESUMO

BACKGROUND: To evaluate the effect of the weighting of input imaging combo and ADC threshold on the performance of the U-Net and to find an optimized input imaging combo and ADC threshold in segmenting acute ischemic stroke (AIS) lesion. METHODS: This study retrospectively enrolled a total of 212 patients having AIS. Four combos, including ADC-ADC-ADC (AAA), DWI-ADC-ADC (DAA), DWI-DWI-ADC (DDA), and DWI-DWI-DWI (DDD), were used as input images, respectively. Three ADC thresholds including 0.6, 0.8 and 1.8 × 10-3 mm2/s were applied. Dice similarity coefficient (DSC) was used to evaluate the segmentation performance of U-Nets. Nonparametric Kruskal-Wallis test with Tukey-Kramer post-hoc tests were used for comparison. A p < .05 was considered statistically significant. RESULTS: The DSC significantly varied among different combos of images and different ADC thresholds. Hybrid U-Nets outperformed uniform U-Nets at ADC thresholds of 0.6 × 10-3 mm2/s and 0.8 × 10-3 mm2/s (p < .001). The U-Net with imaging combo of DDD had segmentation performance similar to hybrid U-Nets at an ADC threshold of 1.8 × 10-3 mm2/s (p = .062 to 1). The U-Net using the imaging combo of DAA at the ADC threshold of 0.6 × 10-3 mm2/s achieved the highest DSC in the segmentation of AIS lesion. CONCLUSIONS: The segmentation performance of U-Net for AIS varies among the input imaging combos and ADC thresholds. The U-Net is optimized by choosing the imaging combo of DAA at an ADC threshold of 0.6 × 10-3 mm2/s in segmentating AIS lesion with highest DSC. KEY POINTS: • Segmentation performance of U-Net for AIS differs among input imaging combos. • Segmentation performance of U-Net for AIS differs among ADC thresholds. • U-Net is optimized using DAA with ADC = 0.6 × 10-3 mm2/s.


Assuntos
AVC Isquêmico , Acidente Vascular Cerebral , Humanos , AVC Isquêmico/diagnóstico por imagem , Imagem de Difusão por Ressonância Magnética/métodos , Estudos Retrospectivos , Acidente Vascular Cerebral/diagnóstico por imagem
2.
Eur Radiol ; 32(8): 5371-5381, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35201408

RESUMO

OBJECTIVES: To examine the role of ADC threshold on agreement across observers and deep learning models (DLMs) plus segmentation performance of DLMs for acute ischemic stroke (AIS). METHODS: Twelve DLMs, which were trained on DWI-ADC-ADC combination from 76 patients with AIS using 6 different ADC thresholds with ground truth manually contoured by 2 observers, were tested by additional 67 patients in the same hospital and another 78 patients in another hospital. Agreement between observers and DLMs were evaluated by Bland-Altman plot and intraclass correlation coefficient (ICC). The similarity between ground truth (GT) defined by observers and between automatic segmentation performed by DLMs was evaluated by Dice similarity coefficient (DSC). Group comparison was performed using the Mann-Whitney U test. The relationship between the DSC and ADC threshold as well as AIS lesion size was evaluated by linear regression analysis. A p < .05 was considered statistically significant. RESULTS: Excellent interobserver agreement and intraobserver repeatability in the manual segmentation (all ICC > 0.98, p < .001) were achieved. The 95% limit of agreement was reduced from 11.23 cm2 for GT on DWI to 0.59 cm2 for prediction at an ADC threshold of 0.6 × 10-3 mm2/s combined with DWI. The segmentation performance of DLMs was improved with an overall DSC from 0.738 ± 0.214 on DWI to 0.971 ± 0.021 on an ADC threshold of 0.6 × 10-3 mm2/s combined with DWI. CONCLUSIONS: Combining an ADC threshold of 0.6 × 10-3 mm2/s with DWI reduces interobserver and inter-DLM difference and achieves best segmentation performance of AIS lesions using DLMs. KEY POINTS: • Higher Dice similarity coefficient (DSC) in predicting acute ischemic stroke lesions was achieved by ADC thresholds combined with DWI than by DWI alone (all p < .05). • DSC had a negative association with the ADC threshold in most sizes, both hospitals, and both observers (most p < .05) and a positive association with the stroke size in all ADC thresholds, both hospitals, and both observers (all p < .001). • An ADC threshold of 0.6 × 10-3 mm2/s eliminated the difference of DSC at any stroke size between observers or between hospitals (p = .07 to > .99).


Assuntos
Aprendizado Profundo , AVC Isquêmico , Acidente Vascular Cerebral , Imagem de Difusão por Ressonância Magnética , Humanos , AVC Isquêmico/diagnóstico por imagem , Variações Dependentes do Observador , Acidente Vascular Cerebral/diagnóstico por imagem
3.
Can J Physiol Pharmacol ; 100(7): 665-678, 2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35856422

RESUMO

Systemic inflammatory response syndrome plays an important role in the development of sepsis. GABAergic and cholinergic pathways activation are considered important for inflammatory response regulation. Tumor necrosis factor (TNF)-α, interleukin (IL)-1ß, IL-12, IL-10, as well as inducible nitric oxide synthase (iNOS)-derived nitric oxide (NO) are important inflammatory mediators involved in the pathogenesis of sepsis. Muscimol, an active compound from the mushroom Amanita muscaria (L.) Lam., is a potent GABAA agonist, inhibits inflammatory response via activating GABAA receptor and vagus nerve. However, the effect of muscimol on lipopolysaccharide (LPS)-induced systemic inflammatory response is still unclear. Therefore, we studied the effects of muscimol on systemic inflammatory response and survival rate in endotoxemic mice. Mice endotoxemia was induced by LPS. Muscimol was given to mice or RAW264.7 cells 30 min before LPS (10 mg/kg, i.p., or 10 ng/mL, respectively). Mice received GABAergic and cholinergic receptor antagonists 30 min before muscimol and LPS. Muscimol decreased TNF-α, IL-1ß, IL-12, iNOS-derived NO, and increased IL-10 levels and survival rate after LPS treatment. Muscimol significantly decreased nuclear factor kappa B (NF-κB) activity, increased IκB expression, and decreased pIKK expression in LPS-treated RAW264.7 cells. GABAergic and cholinergic antagonists failed to reverse muscimol's protection in LPS-treated mice. In conclusion, muscimol protected against systemic inflammatory response in endotoxemic mice may be partially independent of GABAergic and cholinergic receptors.


Assuntos
Endotoxemia , Sepse , Animais , Endotoxemia/induzido quimicamente , Endotoxemia/tratamento farmacológico , Interleucina-10/metabolismo , Interleucina-12/metabolismo , Lipopolissacarídeos/farmacologia , Camundongos , Muscimol/farmacologia , Muscimol/uso terapêutico , NF-kappa B/metabolismo , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Receptores Colinérgicos/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
4.
Zhongguo Zhong Xi Yi Jie He Za Zhi ; 35(10): 1205-9, 2015 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-26677672

RESUMO

OBJECTIVE: To explore the correlation between the recurrence of cerebral infarction and aspirin resistance (AR)/Chinese medical (CM) constitutions. METHODS: Totally 413 cerebral infarction patients took Aspirin Enteric-coated Tablet (100 mg per day) while receiving routine therapy, 5 days at least in a week. They were followed-up for 12 months. Aspirin sensitivity (AS) was determined using turbidimetry. CM constitutions among patients with different AS were compared. Ratios of AR patients and AS patients of different CM constitutions in cerebral infarction recurrent patients were compared. Platelet membrane glycoproteins (GP) II b HPA-3 gene polymorphism was detected by polymerase chain reaction (PCR) method. Correlation between recurrence of cerebral infarction and AR, bb genotypes, CM constitutions times AS were analyzed by Logistic regression. RESULTS: Totally 11 patients dropped out, 101 (25.12%)with recurrent cerebral infarction and 301 (74.88%) without recurrent cerebral infarction. There were 152 (37.81%) AR patients and 250 (62.19%) AS patients. AR accounted for 26.6% (80/ 301) and AS accounted for 73.4% (221/301) in non-recurrent cerebral infarction patients. AR accounted for 71.3% (72/101) and AS accounted for 28.7% (29/101) in recurrent cerebral infarction patients. There was statistical difference in AR and AS ratios (χ2 = 64.287, P = 0.000). The proportion of yin deficiency constitution (YDC) was the largest [28.3% (43/152)] in AR patients. The proportion of blood stasis constitution (BSC) was the largest [23.6% (59/250)] in AS patients. There was statistical difference in CM constitutions between AR patients and AS patients (χ2 = 21.574, P < 0.01). The former 4 recurrent rates occurred in AR patients of YDC, BSC, damp-phlegm constitution (DPC), qi deficiency constitution (QDC). YDC occupied the first place [22.4% (34/152)]. The former 4 recurrent rates occurred in AS patients of BSC, QDC, DPC, damp-heat constitution (DHC). BSC occupied the first place [3.2% (2/250)]. Compared with non-recurrent cerebral infarction patients and AS patients, bb gene occurred most often, but aa gene and ab gene occurred obviously lesser in non-recurrent cerebral infarction patients and AR patients (χ2 = 20.171, χ2 = 55.139, P < 0.01). AR and bb gene were positively correlated with recurrent cerebral infarction (OR = 18.423, P = 0.000; OR = 1.304, P = 0.028). Body constitutions interacted with AS (OR = 0.707, P = 0.000). CONCLUSIONS: Recurrent cerebral infarction was closely related to AR and constitutional types. The recurrence rate was higher in AR patients of YDC. GP I b HPA-3 bb genotype might be a risk factor for AR and recurrent cerebral infarction.


Assuntos
Aspirina/uso terapêutico , Infarto Cerebral , Resistência a Medicamentos , Medicina Tradicional Chinesa , Constituição Corporal , Humanos , Neoplasias , Recidiva , Deficiência da Energia Yin
5.
BMC Genomics ; 15: 793, 2014 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-25218338

RESUMO

BACKGROUND: Phage ZZ1, which efficiently infects pathogenic Acinetobacter baumannii strains, is the fifth completely sequenced T4-like Acinetobacter phage to date. To gain a better understanding of the genetic characteristics of ZZ1, bioinformatics and comparative genomic analyses of the T4 phages were performed. RESULTS: The 166,687-bp double-stranded DNA genome of ZZ1 has the lowest GC content (34.4%) of the sequenced T4-like Acinetobacter phages. A total of 256 protein-coding genes and 8 tRNA genes were predicted. Forty-three percent of the predicted ZZ1 proteins share up to 73% amino acid identity with T4 proteins, and the homologous genes generally retained the same order and transcriptional direction. Beyond the conserved structural and DNA replication modules, T4 and ZZ1 have diverged substantially by the acquisition and deletion of large blocks of unrelated genes, especially in the first halves of their genomes. In addition, ZZ1 and the four other T4-like Acinetobacter phage genomes (Acj9, Acj61, 133, and Ac42) share a well-organised and highly conserved core genome, particularly in the regions encoding DNA replication and virion structural proteins. Of the ZZ1 proteins, 70, 64, 61, and 56% share up to 86, 85, 81, and 83% amino acid identity with Acj9, Acj61, 133, and Ac42 proteins, respectively. ZZ1 has a different number and types of tRNAs than the other 4 Acinetobacter phages, although some of the ZZ1-encoded tRNAs share high sequence similarity with the tRNAs from these phages. Over half of ZZ1-encoded tRNAs (5 out of 8) are related to optimal codon usage for ZZ1 proteins. However, this correlation was not present in any of the other 4 Acinetobacter phages. CONCLUSIONS: The comparative genomic analysis of these phages provided some new insights into the evolution and diversity of Acinetobacter phages, which might elucidate the evolutionary origin and host-specific adaptation of these phages.


Assuntos
Acinetobacter/virologia , Bacteriófago T4/genética , Bacteriófago T4/fisiologia , Genoma Viral/genética , Composição de Bases , Códon/genética , Elementos de DNA Transponíveis/genética , Evolução Molecular , Genômica , Anotação de Sequência Molecular , Filogenia , RNA de Transferência/genética
6.
Eur Radiol Exp ; 8(1): 19, 2024 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-38347188

RESUMO

BACKGROUND: A dual-function phantom designed to quantify the apparent diffusion coefficient (ADC) in different fat contents (FCs) and glass bead densities (GBDs) to simulate the human tissues has not been documented yet. We propose a dual-function phantom to quantify the FC and to measure the ADC at different FCs and different GBDs. METHODS: A fat-containing diffusion phantom comprised by 30 glass-bead-containing fat-water emulsions consisting of six different FCs (0, 10, 20, 30, 40, and 50%) multiplied by five different GBDs (0, 0.1, 0.25, 0.5, and 1.0 g/50 mL). The FC and ADC were measured by the "iterative decomposition of water and fat with echo asymmetry and least squares estimation-IQ," IDEAL-IQ, and single-shot echo-planar diffusion-weighted imaging, SS-EP-DWI, sequences, respectively. Linear regression analysis was used to evaluate the relationship among the fat fraction (FF) measured by IDEAL-IQ, GBD, and ADC. RESULTS: The ADC was significantly, negatively, and linearly associated with the FF (the linear slope ranged from -0.005 to -0.017, R2 = 0.925 to 0.986, all p < 0.001). The slope of the linear relationship between the ADC and the FF, however, varied among different GBDs (the higher the GBD, the lower the slope). ADCs among emulsions across different GBDs and FFs were overlapped. Emulsions with low GBDs plus high FFs shared a same lower ADC range with those with median or high GBDs plus median or lower FFs. CONCLUSIONS: A novel dual-function phantom simulating the human tissues allowed to quantify the influence of FC and GBD on ADC. RELEVANCE STATEMENT: The study developed an innovative dual-function MRI phantom to explore the impact of FC on ADC variation that can affect clinical results. The results revealed the superimposed effect on FF and GBD density on ADC measurements. KEY POINTS: • A dual-function phantom made of glass bead density (GBD) and fat fraction (FF) emulsion has been developed. • Apparent diffusion coefficient (ADC) values are determined by GBD and FF. • The dual-function phantom showed the mutual ADC addition between FF and GBD.


Assuntos
Imagem de Difusão por Ressonância Magnética , Imageamento por Ressonância Magnética , Humanos , Imagem de Difusão por Ressonância Magnética/métodos , Imagem Ecoplanar , Água , Imagens de Fantasmas
7.
Exploration (Beijing) ; 3(3): 20220005, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37933377

RESUMO

The unclear structures and polydispersity of metal nanoparticles (NPs) seriously hamper the identification of the active sites and the construction of structure-reactivity relationships. Fortunately, ligand-protected metal nanoclusters (NCs) with atomically precise structures and monodispersity have become an ideal candidate for understanding the well-defined correlations between structure and catalytic property at an atomic level. The programmable kernel structures of atomically precise metal NCs provide a fantastic chance to modulate their size, shape, atomic arrangement, and electron state by the precise modulating of the number, type, and location of metal atoms. Thus, the special focus of this review highlights the most recent process in tailoring the catalytic activity and selectivity over metal NCs by precisely controlling their kernel structures. This review is expected to shed light on the in-depth understanding of metal NCs' kernel structures and reactivity relationships.

8.
Exp Ther Med ; 25(1): 35, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36569435

RESUMO

Ginsenoside Rh2 (GRh2) is a monomer isolated from red ginseng that has extensive pharmacological effects. However, whether GRh2 has a protective effect on ischaemia/reperfusion (I/R) in the myocardium has yet to be elucidated. The present study aimed to identify the anti-inflammatory and antioxidant effects of GRh2 on I/R in the myocardium and its underlying mechanism. A rat model of myocardial I/R injury was constructed by ligating the left anterior descending coronary artery, which was subsequently treated with GRh2. A total of 40 male Sprague-Dawley rats were divided into the following four groups: The sham group, the I/R group, the I/R+GRh2 (10 mg/kg) group and the I/R+GRh2 (20 mg/kg) group. Neonatal rat cardiomyocytes were also used to evaluate the protective effect of GRh2 on hypoxia/reoxygenation (H/R)-induced myocardial injury in vitro. The GRh2 pre-treatment reduced the I/R- or H/R-induced release of myocardial enzymes and the production of IL-1ß, IL-18 and TNF-α. GRh2 reduced the area of myocardial infarction and the histological changes in the myocardium and improved cardiac functions. In addition, GRh2 reduced the expression levels of NOD-like receptor family pyrin domain-containing 3 (NLRP3), apoptosis-associated speck-like protein, caspase-1, malondialdehyde and reactive oxygen species and increased the expression levels of nuclear factor E2-related factor 2 (Nrf2), heme oxygenase-1 (HO-1), glutathione peroxidase and superoxide dismutase. In conclusion, the present study confirmed that GRh2 could reduce oxidative stress and inflammation in cardiomyocytes after reperfusion, and its mechanism of action may be related to its regulation of the Nrf2/HO-1/NLRP3 signalling pathway.

9.
BMC Microbiol ; 12: 156, 2012 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-22838726

RESUMO

BACKGROUND: Acinetobacter baumannii, a significant nosocomial pathogen, has evolved resistance to almost all conventional antimicrobial drugs. Bacteriophage therapy is a potential alternative treatment for multidrug-resistant bacterial infections. In this study, one lytic bacteriophage, ZZ1, which infects A. baumannii and has a broad host range, was selected for characterization. RESULTS: Phage ZZ1 and 3 of its natural hosts, A. baumanni clinical isolates AB09V, AB0902, and AB0901, are described in this study. The 3 strains have different sensitivities to ZZ1, but they have the same sensitivity to antibiotics. They are resistant to almost all of the antibiotics tested, except for polymyxin. Several aspects of the life cycle of ZZ1 were investigated using the sensitive strain AB09V under optimal growth conditions. ZZ1 is highly infectious with a short latent period (9 min) and a large burst size (200 PFU/cell). It exhibited the most powerful antibacterial activity at temperatures ranging from 35°C to 39°C. Moreover, when ZZ1 alone was incubated at different pHs and different temperatures, the phage was stable over a wide pH range (4 to 9) and at extreme temperatures (between 50°C and 60°C). ZZ1 possesses a 100-nm icosahedral head containing double-stranded DNA with a total length of 166,682 bp and a 120-nm long contractile tail. Morphologically, it could be classified as a member of the Myoviridae family and the Caudovirales order. Bioinformatic analysis of the phage whole genome sequence further suggested that ZZ1 was more likely to be a new member of the Myoviridae phages. Most of the predicted ORFs of the phage were similar to the predicted ORFs from other Acinetobacter phages. CONCLUSION: The phage ZZ1 has a relatively broad lytic spectrum, high pH stability, strong heat resistance, and efficient antibacterial potential at body temperature. These characteristics greatly increase the utility of this phage as an antibacterial agent; thus, it should be further investigated.


Assuntos
Acinetobacter baumannii/virologia , Bacteriófagos/isolamento & purificação , Bacteriófagos/fisiologia , Infecções por Acinetobacter/microbiologia , Acinetobacter baumannii/efeitos dos fármacos , Acinetobacter baumannii/isolamento & purificação , Antibacterianos/farmacologia , Bacteriófagos/genética , Bacteriófagos/ultraestrutura , Caudovirales/genética , Caudovirales/isolamento & purificação , Caudovirales/fisiologia , Caudovirales/ultraestrutura , DNA Viral/química , DNA Viral/genética , Farmacorresistência Bacteriana Múltipla , Ordem dos Genes , Genoma Viral , Especificidade de Hospedeiro , Humanos , Concentração de Íons de Hidrogênio , Viabilidade Microbiana/efeitos dos fármacos , Viabilidade Microbiana/efeitos da radiação , Dados de Sequência Molecular , Myoviridae/genética , Myoviridae/isolamento & purificação , Myoviridae/fisiologia , Myoviridae/ultraestrutura , Fases de Leitura Aberta , Análise de Sequência de DNA , Temperatura , Vírion/ultraestrutura
10.
Biomedicines ; 10(1)2022 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-35052864

RESUMO

Ribosome biogenesis is a cellular process critical for protein homeostasis during cell growth and multiplication. Our previous study confirmed up-regulation of ribosome biogenesis during endometriosis progression and malignant transition, thus anti-ribosome biogenesis may be effective for treating endometriosis and the associated complications. A mouse model with human endometriosis features was established and treated with three different drugs that can block ribosome biogenesis, including inhibitors against mTOR/PI3K (GSK2126458) and RNA polymerase I (CX5461 and BMH21). The average lesion numbers and disease frequencies were significantly reduced in treated mice as compared to controls treated with vehicle. Flow cytometry analyses confirmed the reduction of small peritoneal macrophage and neutrophil populations with increased large versus small macrophage ratios, suggesting inflammation suppression by drug treatments. Lesions in treated mice also showed lower nerve fiber density which can support the finding of pain-relief by behavioral studies. Our study therefore suggested ribosome biogenesis as a potential therapeutic target for treating endometriosis.

11.
Antimicrob Agents Chemother ; 55(6): 2532-6, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21402854

RESUMO

The aim of the study was to investigate the effect of sesame oil on acute kidney injury induced by the synergistic action of aminoglycoside and iodinated contrast in rats. Acute kidney injury was induced by a 5-day course of daily gentamicin injections (100 mg/kg of body weight, subcutaneously) and then iodinated contrast (4 ml/kg, intravenously) in male specific-pathogen-free Sprague-Dawley rats. Sesame oil (0.5 ml/kg, orally) was given 1 h before iodinated contrast. Renal function and oxidative stress were assessed 6 h after iodinated contrast injection. Renal function was evaluated by measuring serum blood urea nitrogen and creatinine levels. Renal oxidative stress was assessed by determining renal lipid peroxidation, myeloperoxidase, hydroxyl radical, superoxide anion, nitrite/nitrate, and inducible nitric oxide synthase levels. Sesame oil significantly prevented the rise of serum blood urea nitrogen and creatinine levels. Furthermore, there was a parallel inhibition of the rise in levels of expression of renal lipid peroxidation, myeloperoxidase, hydroxyl radicals, superoxide anion, nitrite/nitrate, and inducible nitric oxide synthase in rats with gentamicin-plus-iodinated contrast-induced acute kidney injury. We conclude that sesame oil may attenuate aminoglycoside-plus-iodinated contrast-induced acute kidney injury by inhibiting renal oxidative stress in rats.


Assuntos
Injúria Renal Aguda/prevenção & controle , Aminoglicosídeos/toxicidade , Antibacterianos/toxicidade , Meios de Contraste/toxicidade , Iotalamato de Meglumina/toxicidade , Óleo de Gergelim/farmacologia , Injúria Renal Aguda/induzido quimicamente , Animais , Rim/patologia , Masculino , Óxido Nítrico/biossíntese , Estresse Oxidativo , Ratos , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo
12.
Nanoscale ; 12(20): 10944-10948, 2020 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-32400793

RESUMO

Two polyoxometalate (POM)-based thiolate-protected silver coordination polymers were obtained using different Lindquist-type POM precursors under the same conditions. [Ag10(StBu)6(CH3CN)8(Mo6O19)2·2CH3CN]n (abbreviated as Ag10-Mo6) was observed to feature chain-like structures containing Ag10 clusters linked by [Mo6O19]2- anions through Ag-O bonds and to exhibit unprecedented green photoluminescence at room temperature. Interestingly, [Ag18(StBu)12(CH3CN)5(Mo6O19)2·Mo6O19·2CH3CN]n (abbreviated as Ag18-Mo6) was found to contain 20-membered cycle-Ag10S10 each with a diameter of approximately 11.382 Å and constructed from alternating silver and sulfur atoms and interconnected into an elegant Ag-S sheet by interstitial the Ag3StBu and AgCH3CN motifs, and to also contain [Mo6O19]2- counter ions filling in the spaces made by the cycle-Ag10S10 and strengthening the structure by forming Ag-O bonds. Such a stacking structure for thiolate-protected silver compounds has not been previously reported.

13.
Chem Commun (Camb) ; 56(14): 2091-2094, 2020 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-31960846

RESUMO

Silver chalcogenide wires are assembled for the first time using a linear fluorinated carboxylate ligand into a metal-organic framework (MOF) with multifunctional properties. Fluorinated ligands in the host framework endow the MOF with excellent hydrophobicity. More interestingly, it displays typical semiconductivity due to the ordered nanoarray of non-discrete helical (-Ag-S-)n chains.

14.
Anal Bioanal Chem ; 391(8): 2905-14, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18575852

RESUMO

A selective molecularly imprinted solid-phase extraction (MISPE) for indomethacin (IDM) from water samples was developed. Using IDM as template molecule, acrylamide (AM) or methacrylic acid (MAA) as functional monomer, ethylene dimethacrylate (EDMA) as crosslinker, and bulk or suspension polymerization as the synthetic method, three molecularly imprinted polymers (MIPs) were synthesized and characterized with a rebinding experiment. It was found that the MIP of AM-EDMA produced by bulk polymerization showed the highest binding capacity for IDM, and so it was chosen for subsequent experiments, such as those testing the selectivity and recognition binding sites. Scatchard analysis revealed that at least two kinds of binding sites formed in the MIP, with the dissociation constants of 7.8 micromol L(-1) and 127.2 micromol L(-1), respectively. Besides IDM, three structurally related compounds--acemetacin, oxaprozin and ibuprofen--were employed for selectivity tests. It was observed that the MIP exhibited the highest selective rebinding to IDM. Accordingly, the MIP was used as a solid-phase extraction sorbent for the extraction and enrichment of IDM in water samples. The extraction conditions of the MISPE column for IDM were optimized to be: chloroform or water as loading solvent, chloroform with 20% acetonitrile as washing solution, and methanol as eluting solvent. Water samples with or without spiking were extracted by the MISPE column and analyzed by HPLC. No detectable IDM was observed in tap water and the content of IDM in a river water sample was found to be 1.8 ng mL(-1). The extraction efficiencies of the MISPE column for IDM in spiked tap and river water were acceptable (87.2% and 83.5%, respectively), demonstrating the feasibility of the prepared MIP for IDM extraction.


Assuntos
Indometacina/análise , Impressão Molecular/métodos , Polímeros/química , Extração em Fase Sólida/métodos , Água/química , Anti-Inflamatórios não Esteroides/análise , Anti-Inflamatórios não Esteroides/química , Clorofórmio/química , Cromatografia Líquida de Alta Pressão , Estudos de Viabilidade , Indometacina/química , Estrutura Molecular , Rios/química , Soluções/química , Espectrofotometria , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/química
15.
JPEN J Parenter Enteral Nutr ; 32(3): 276-80, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18443139

RESUMO

BACKGROUND: Sepsis is one of the major causes of death reported in intensive care units. A daily supplement of sesame oil for 1 week significantly attenuates oxidative stress-associated hepatic injury in septic rats. However, the excess intake of sesame oil may be associated with a health risk. This study investigates the effect of accumulative sesame oil on oxidative stress-associated hepatic injury after cecal ligation and puncture in rats. METHODS: Sesame oil was administered daily (4 mL/kg/d, orally) to rats, and the total intake of sesame oil ranged from 0 (control) to 140 mL/kg before cecal ligation and puncture in 9 groups of rats. Oxidative stress was examined by determining the levels of lipid peroxidation and glutathione. Hepatic injury was evaluated by measuring serum levels of aspartate aminotransferase and alkaline phosphatase. RESULTS: Rats that received sesame oil for 4 and 5 weeks had a lower body weight gain compared with those that received saline. Lipid peroxidation was decreased in the 20-mL/kg and 28-mL/kg groups, but it was increased in the 140-mL/kg group compared with the control group. Glutathione levels were increased in the < or =28-mL/kg groups compared with the control group. Serum levels of aspartate aminotransferase and alkaline phosphatase were reduced in the < or =28-mL/kg groups compared with the control group. CONCLUSION: Sesame oil does not demonstrate accumulatively enhanced protection against oxidative stress-associated hepatic injury after cecal ligation and puncture in rats.


Assuntos
Ceco/lesões , Peroxidação de Lipídeos/efeitos dos fármacos , Fígado/lesões , Estresse Oxidativo/efeitos dos fármacos , Óleo de Gergelim/farmacologia , Animais , Ceco/cirurgia , Relação Dose-Resposta a Droga , Glutationa/metabolismo , Fígado/enzimologia , Masculino , Distribuição Aleatória , Ratos , Ratos Wistar , Sepse , Organismos Livres de Patógenos Específicos , Aumento de Peso
16.
JPEN J Parenter Enteral Nutr ; 32(2): 154-9, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18407908

RESUMO

BACKGROUND: Sepsis is a major cause of mortality in the intensive care unit. Oxidative stress plays an important role in the pathogenesis of organ failure during sepsis. Sesame oil decreases circulating oxygen free radicals in septic rats; however, its effect on hepatic oxidative status is unknown. The authors examined the effect of sesame oil on hepatic lipid peroxidation in septic rats. METHODS: Hepatic injury was induced using cecal ligation and puncture (CLP). Rats were divided into 4 groups: sham, rats given a sham operation without CLP; SO, rats given sesame oil alone; CLP, rats given saline and then CLP; and CS, rats given sesame oil and then CLP. All rats were first given a 1-week daily oral supplement of sesame oil or saline (4 mL/kg/d) and then CLP or a sham operation. The authors assessed hepatic oxidative stress by determining hepatic lipid peroxidation, hydroxyl radical, superoxide anion, and nitric oxide levels 12 hours after CLP. They also assessed xanthine oxidase activity and nitric oxide synthase expression. RESULTS: Hepatic lipid peroxidation (P < .0001), hydroxyl radical (P < .05), superoxide anion (P < .05), and nitrite (P < .05) levels were significantly lower in sesame oil-treated septic rats. Furthermore, sesame oil significantly reduced xanthine oxidase activity (P < .01) and inducible nitric oxide synthase expression (P < .005) in septic rats. CONCLUSIONS: Sesame oil might attenuate hepatic lipid peroxidation by inhibiting superoxide anion and nitric oxide, at least partially, in experimental septic rats.


Assuntos
Peroxidação de Lipídeos/efeitos dos fármacos , Fígado/metabolismo , Óxido Nítrico/antagonistas & inibidores , Óleo de Gergelim/farmacologia , Superóxidos/metabolismo , Análise de Variância , Animais , Ceco/lesões , Ceco/patologia , Ceco/cirurgia , Radical Hidroxila , Ligadura , Fígado/enzimologia , Fígado/lesões , Masculino , Óxido Nítrico Sintase Tipo II/efeitos dos fármacos , Óxido Nítrico Sintase Tipo II/metabolismo , Nitritos/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Distribuição Aleatória , Ratos , Ratos Wistar , Espécies Reativas de Oxigênio , Sepse/prevenção & controle , Organismos Livres de Patógenos Específicos , Xantina Oxidase/efeitos dos fármacos , Xantina Oxidase/metabolismo
17.
Zhong Yao Cai ; 31(7): 998-1000, 2008 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-18973014

RESUMO

OBJECTIVE: To study the aqueous chemical constituents of the flower buds of Eugenia caryophylla. METHODS: The compounds were isolated by HP-20 resin column chromatography, RP-C18 column chromatography, preparative RP-C18 thin-layer chromatography, preparative RP-C18 high performance liquid chromatography, and their structures were established by NMR and MS evidences. RESULTS: Five compounds were separated from the water extracts. Their structures were identified as quercetin-3-O-glucuronide (1), quercetin-3-O-glucuronide 6"-methyl ester (2), quercetin-3-O-glucopy-ranoside (3) , eugenyl-beta-rutinoside (4) and myricetin (5). CONCLUSION: Compounds 1-4 are isolated from the genus for the first time.


Assuntos
Glucosídeos/isolamento & purificação , Plantas Medicinais/química , Quercetina/análogos & derivados , Syzygium/química , Cromatografia Líquida de Alta Pressão , Flavonoides/química , Flavonoides/isolamento & purificação , Flores/química , Glucosídeos/química , Espectroscopia de Ressonância Magnética , Quercetina/química , Quercetina/isolamento & purificação
18.
PLoS One ; 13(2): e0192411, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29438424

RESUMO

PURPOSE: We estimated the volume of vestibular schwannomas by an ice cream cone formula using thin-sliced magnetic resonance images (MRI) and compared the estimation accuracy among different estimating formulas and between different models. METHODS: The study was approved by a local institutional review board. A total of 100 patients with vestibular schwannomas examined by MRI between January 2011 and November 2015 were enrolled retrospectively. Informed consent was waived. Volumes of vestibular schwannomas were estimated by cuboidal, ellipsoidal, and spherical formulas based on a one-component model, and cuboidal, ellipsoidal, Linskey's, and ice cream cone formulas based on a two-component model. The estimated volumes were compared to the volumes measured by planimetry. Intraobserver reproducibility and interobserver agreement was tested. Estimation error, including absolute percentage error (APE) and percentage error (PE), was calculated. Statistical analysis included intraclass correlation coefficient (ICC), linear regression analysis, one-way analysis of variance, and paired t-tests with P < 0.05 considered statistically significant. RESULTS: Overall tumor size was 4.80 ± 6.8 mL (mean ±standard deviation). All ICCs were no less than 0.992, suggestive of high intraobserver reproducibility and high interobserver agreement. Cuboidal formulas significantly overestimated the tumor volume by a factor of 1.9 to 2.4 (P ≤ 0.001). The one-component ellipsoidal and spherical formulas overestimated the tumor volume with an APE of 20.3% and 29.2%, respectively. The two-component ice cream cone method, and ellipsoidal and Linskey's formulas significantly reduced the APE to 11.0%, 10.1%, and 12.5%, respectively (all P < 0.001). CONCLUSION: The ice cream cone method and other two-component formulas including the ellipsoidal and Linskey's formulas allow for estimation of vestibular schwannoma volume more accurately than all one-component formulas.


Assuntos
Imageamento por Ressonância Magnética/métodos , Neuroma Acústico/diagnóstico por imagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neuroma Acústico/patologia , Reprodutibilidade dos Testes , Adulto Jovem
19.
Shock ; 27(3): 334-7, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17304116

RESUMO

Lead (Pb) increases lipopolysaccharide (LPS)-induced tumor necrosis factor alpha, which causes liver damage. In this study, we investigated the effect of sesame oil on Pb-plus-LPS (Pb + LPS)-induced acute liver damage in mice. Mice were given sesame oil (8 mL/kg orally) just after Pb acetate (10 mmol/kg i.p.) plus LPS (5 mg/kg i.p.). Aspartate aminotransferase, alanine aminotransferase, tumor necrosis factor-alpha, interleukin-1beta, nitric oxide, and inducible nitric oxide synthase levels were examined. Sesame oil significantly decreased serum aspartate aminotransferase and alanine aminotransferase levels in Pb + LPS-stimulated mice. Sesame oil reduced Pb + LPS-induced tumor necrosis factor-alpha, interleukin-1beta, and nitric oxide production in serum and liver tissue. Furthermore, sesame oil decreased inducible nitric oxide synthase expression in leukocytes and liver tissue in Pb + LPS-treated mice. We hypothesize that the inhibition of proinflammatory cytokines and nitric oxide might be involved in sesame oil-associated protection against Pb + LPS-induced acute hepatic injury in mice.


Assuntos
Lipopolissacarídeos/metabolismo , Fígado/lesões , Fígado/patologia , Óleo de Gergelim/farmacologia , Animais , Western Blotting , Citocinas/metabolismo , Inflamação , Interleucina-1beta/metabolismo , Chumbo/farmacologia , Fígado/metabolismo , Camundongos , Camundongos Endogâmicos ICR , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Nitritos/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
20.
Shock ; 27(2): 199-204, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17224796

RESUMO

Although cisplatin (cis-diamminedichloroplatinum) is an effective drug for the treatment of several solid tumors and has been used therapeutically for decades, several cisplatin-induced side effects have limited its therapeutic dosage in clinical studies. Our aim was to examine the effect of sesame oil on cisplatin-induced hepatic and renal injuries in mice (8-week-old female SPF C57BL/6) given subcutaneous cisplatin (0, 5, 10, or 20 mg/kg). Hepatic and renal functions, lipid peroxidation (LPO) levels, and reactive oxygen free radicals were evaluated 3 days after cisplatin administration, and tumor volumes were recorded 0, 3, 6, and 9 days after cisplatin administration. Sesame oil (i) potently attenuated cisplatin-associated hepatic and renal injuries; (ii) decreased cisplatin-initiated LPO as well as the production of hydroxyl radical, peroxynitrite, and nitrite in blood and tissue; and (iii) did not affect the antitumor capacity exerted by cisplatin in mice with melanoma. We suggest that sesame oil attenuates cisplatin-induced hepatic and renal damage by at least partially inhibiting nitric oxide-associated LPO in mice. Sesame oil might be a new approach for preventing cisplatin-induced multiple organ injury during the treatment of tumors.


Assuntos
Antineoplásicos/toxicidade , Cisplatino/toxicidade , Rim/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Fígado/metabolismo , Óxido Nítrico/metabolismo , Óleo de Gergelim/farmacologia , Animais , Antineoplásicos/uso terapêutico , Cisplatino/uso terapêutico , Relação Dose-Resposta a Droga , Feminino , Rim/lesões , Rim/patologia , Fígado/lesões , Fígado/patologia , Melanoma/tratamento farmacológico , Camundongos , Oxirredução/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo
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