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1.
Int J Antimicrob Agents ; 64(2): 107216, 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38795926

RESUMO

The emergence of multidrug-resistant pathogens has outpaced the development of new antibiotics, leading to renewed interest in endolysins. Endolysins have been investigated as novel biocontrol agents for Gram-positive bacteria. However, their efficacy against Gram-negative species is limited by the barrier presented by their outer membrane, which prevents endolysin access to the peptidoglycan substrate. Here, we used the translocation domain of botulinum neurotoxin to deliver endolysin across the outer membrane of Gram-negative bacteria. The translocation domain selectively interacts with and penetrates membranes composed of anionic lipids, which have been used in nature to deliver various proteins into animal cells. In addition to the botulinum neurotoxin translocation domain, we have fused bacteriophage-derived receptor binding protein to endolysins. This allows the attached protein to efficiently bind to a broad spectrum of Gram-negative bacteria. By attaching these target-binding and translocation machineries to endolysins, we aimed to develop an engineered endolysin with broad-spectrum targeting and enhanced antibacterial activity against Gram-negative species. To validate our strategy, we designed engineered endolysins using two well-known endolysins, T5 and LysPA26, and tested them against 23 strains from six species of Gram-negative bacteria, confirming that our machinery can act broadly. In particular, we observed a 2.32 log reduction in 30 min with only 0.5 µM against an Acinetobacter baumannii isolate. We also used the SpyTag/SpyCatcher system to easily attach target-binding proteins, thereby improving its target-binding ability. Overall, our newly developed endolysin engineering strategy may be a promising approach to control multidrug-resistant Gram-negative bacterial strains.

3.
Adv Healthc Mater ; 13(14): e2302803, 2024 06.
Artigo em Inglês | MEDLINE | ID: mdl-38329411

RESUMO

The decreasing efficacy of antiviral drugs due to viral mutations highlights the challenge of developing a single agent targeting multiple strains. Using host cell viral receptors as competitive inhibitors is promising, but their low potency and membrane-bound nature have limited this strategy. In this study, the authors show that angiotensin-converting enzyme 2 (ACE2) in a planar membrane patch can effectively neutralize all tested severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants that emerged during the COVID-19 pandemic. The ACE2-incorporated membrane patch implemented using nanodiscs replicated the spike-mediated membrane fusion process outside the host cell, resulting in virus lysis, extracellular RNA release, and potent antiviral activity. While neutralizing antibodies became ineffective as the SARS-CoV-2 evolved to better penetrate host cells the ACE2-incorporated nanodiscs became more potent, highlighting the advantages of using receptor-incorporated nanodiscs for antiviral purposes. ACE2-incorporated immunodisc, an Fc fusion nanodisc developed in this study, completely protected humanized mice infected with SARS-CoV-2 after prolonged retention in the airways. This study demonstrates that the incorporation of viral receptors into immunodisc transforms the entry gate into a potent virucide for all current and future variants, a concept that can be extended to different viruses.


Assuntos
Enzima de Conversão de Angiotensina 2 , Anticorpos Neutralizantes , COVID-19 , SARS-CoV-2 , Animais , Enzima de Conversão de Angiotensina 2/metabolismo , Enzima de Conversão de Angiotensina 2/química , Humanos , Camundongos , COVID-19/virologia , Anticorpos Neutralizantes/imunologia , Anticorpos Neutralizantes/farmacologia , Antivirais/farmacologia , Antivirais/química , Glicoproteína da Espícula de Coronavírus/metabolismo , Glicoproteína da Espícula de Coronavírus/imunologia , Glicoproteína da Espícula de Coronavírus/química , Chlorocebus aethiops , Células Vero , Internalização do Vírus/efeitos dos fármacos , Células HEK293 , Anticorpos Antivirais/imunologia
5.
Polymers (Basel) ; 15(3)2023 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-36771983

RESUMO

Coffee waste is an abundant biomass that can be converted into high value chemical products, and is used in various renewable biological processes. In this study, oil was extracted from spent coffee grounds (SCGs) and used for polyhydroxyalkanoate (PHA) production through Pseudomonas resinovorans. The oil-extracted SCGs (OESCGs) were hydrolyzed and used for biohydrogen production through Clostridium butyricum DSM10702. The oil extraction yield through n-hexane was 14.4%, which accounted for 97% of the oil present in the SCGs. OESCG hydrolysate (OESCGH) had a sugar concentration of 32.26 g/L, which was 15.4% higher than that of the SCG hydrolysate (SCGH) (27.96 g/L). Hydrogen production using these substrates was 181.19 mL and 136.58 mL in OESCGH and SCGH media, respectively. The consumed sugar concentration was 6.77 g/L in OESCGH and 5.09 g/L in SCGH media. VFA production with OESCGH (3.58 g/L) increased by 40.9% compared with SCGH (2.54 g/L). In addition, in a fed-batch culture using the extracted oil, cell dry weight was 5.4 g/L, PHA was 1.6 g/L, and PHA contents were 29.5% at 24 h.

6.
Int J Biol Macromol ; 225: 757-766, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36400208

RESUMO

Phasin is a surface-binding protein of polyhydroxyalkanoate (PHA) granules that is encoded by the phaP gene. As its expression increases, PHA granules become smaller, to increase their surface area, and are densely packed inside the cell, thereby increasing the PHA content. A wide range of PHA-producing bacteria have phaP genes; however, their PHA productivity differs, although they are derived from the cognate bacterial host cell. Modulating phasin expression could be a new strategy to enhance PHA production. This study aimed to characterize the effect of heterologous phasins on the reconstitution of E. coli BL21(DE3) and determine the best synergistic phaP gene combination to produce polyhydroxybutyrate (PHB). We identified novel phasins from a PHB high-producer strain, Halomonas sp. YLGW01, and introduced a combination of phaP genes into Escherichia coli. The resulting E. coli phaP1,3 strain had enhanced PHB production by 2.9-fold, leading to increased cell mass and increased PHB content from 48 % to 65 %. This strain also showed increased tolerance to inhibitors, such as furfural and vanillin, enabling the utilization of lignocellulose biosugar as a carbon source. These results suggested that the combination of phaP1 and phaP3 genes from H. sp. YLGW01 could increase PHB production and robustness.


Assuntos
Escherichia coli , Lectinas de Plantas , Escherichia coli/genética , Escherichia coli/metabolismo , Lectinas de Plantas/metabolismo , Proteínas de Bactérias/química , Hidroxibutiratos/metabolismo , Poliésteres/metabolismo
7.
J Chem Inf Model ; 61(1): 36-45, 2021 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-33252229

RESUMO

Following identification of a target protein, hit identification, which finds small organic molecules that bind to the target, is an important first step of a structure-based drug design project. In this study, we demonstrate a target-specific drug design method that can autonomously generate a series of target-favorable compounds. This method utilizes the seq2seq model based on a deep learning algorithm and a water pharmacophore. Water pharmacophore models are used to screen compounds that are favorable to a given target in a large compound database, and seq2seq compound generators are used to train the screened compounds and generate entirely new compounds based on the training model. Our method was tested through binding energy calculation studies of six pharmaceutically relevant targets in the directory of useful decoys (DUD) set with docking. The compounds generated by our method had lower average binding energies than decoy compounds in five out of six cases and included a number of compounds that had lower binding energies than the average binding energies of the active compounds in four cases. The generated compound lists for these four cases featured compounds with lower binding energies than even the most active compounds.


Assuntos
Aprendizado Profundo , Desenho de Fármacos , Algoritmos , Ligantes , Simulação de Acoplamento Molecular , Proteínas , Água
8.
Molecules ; 23(3)2018 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-29558403

RESUMO

Obesity is a public concern and is responsible for various metabolic diseases. Xylobiose (XB), an alternative sweetener, is a major component of xylo-oligosaccharide. The purpose of this study was to investigate the effects of XB on obesity and its associated metabolic changes in related organs. For these studies, mice received a 60% high-fat diet supplemented with 15% d-xylose, 10% XB, or 15% XB as part of the total sucrose content of the diet for ten weeks. Body weight, fat and liver weights, fasting blood glucose, and blood lipids levels were significantly reduced with XB supplementation. Levels of leptin and adipokine were also improved and lipogenic and adipogenic genes in mesenteric fat and liver were down-regulated with XB supplementation. Furthermore, pro-inflammatory cytokines, fatty acid uptake, lipolysis, and ß-oxidation-related gene expression levels in mesenteric fat were down-regulated with XB supplementation. Thus, XB exhibited therapeutic potential for treating obesity which involved suppression of fat deposition and obesity-related metabolic disorders.


Assuntos
Tecido Adiposo/metabolismo , Adiposidade/efeitos dos fármacos , Dissacarídeos/farmacologia , Dissacarídeos/uso terapêutico , Obesidade/tratamento farmacológico , Obesidade/metabolismo , Adipogenia/efeitos dos fármacos , Adipogenia/genética , Tecido Adiposo/efeitos dos fármacos , Animais , Glicemia/metabolismo , Peso Corporal/efeitos dos fármacos , Citocinas/metabolismo , Dieta Hiperlipídica , Ácidos Graxos/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Mediadores da Inflamação/metabolismo , Lipídeos/sangue , Lipogênese/efeitos dos fármacos , Lipogênese/genética , Lipólise/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Camundongos Endogâmicos C57BL , Obesidade/genética , Obesidade/prevenção & controle , Tamanho do Órgão/efeitos dos fármacos , Oxirredução
9.
Nutrients ; 8(12)2016 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-27929393

RESUMO

Type 2 diabetes is a major public health concern worldwide. Xylobiose (XB) consists of two molecules of d-xylose and is a major disaccharide in xylooligosaccharides that are used as prebiotics. We hypothesized that XB could regulate diabetes-related metabolic and genetic changes via microRNA expression in db/db mice. For six weeks, C57BL/KsJ-db/db mice received 5% XB as part of the total sucrose content of their diet. XB supplementation improved glucose tolerance with reduced levels of OGTT AUC, fasting blood glucose, HbA1c, insulin, and HOMA-IR. Furthermore, XB supplementation decreased the levels of total triglycerides, total cholesterol, and LDL-C. The expression levels of miR-122a and miR-33a were higher and lower in the XB group, respectively. In the liver, expressions of the lipogenic genes, including, fatty acid synthase (FAS), peroxisome proliferator activated receptor γ (PPARγ), sterol regulatory element-binding protein-1C (SREBP-1C), sterol regulatory element-binding protein-2 (SREBP-2), acetyl-CoA carboxylase (ACC), HMG-CoA reductase (HMGCR), ATP-binding cassette transporter G5/G8 (ABCG5/8), cholesterol 7 alpha-hydroxylase (CYP7A1), and sterol 12-alpha-hydroxylase (CYP8B1), as well as oxidative stress markers, including superoxide dismutase 1 (SOD1), superoxide dismutase 2 (SOD2), glutathione peroxidase (GPX), and catalase, were also regulated by XB supplementation. XB supplementation inhibited the mRNA expressions levels of the pro-inflammatory cytokines, tumor necrosis factor (TNF)-α, interleukin (IL)-1ß, interleukin (IL)-6, and monocyte chemoattractant protein (MCP)-1, as well as phosphorylation of c-Jun N-terminal kinase/stress activated protein kinase (JNK/SAPK), p38 mitogen-activated protein kinases (MAPK), and extracellular signal-regulated kinases 1/2 (ERK1/2). These data demonstrate that XB exhibits anti-diabetic, hypolipogenic, and anti-inflammatory effects via regulation of the miR-122a/33a axis in db/db mice.


Assuntos
Diabetes Mellitus Experimental/terapia , Dissacarídeos/administração & dosagem , Lipogênese/fisiologia , MicroRNAs/metabolismo , Edulcorantes/administração & dosagem , Animais , Diabetes Mellitus Experimental/metabolismo , Suplementos Nutricionais , Lipogênese/genética , Fígado/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Prebióticos/administração & dosagem
10.
Nutr Res Pract ; 10(1): 11-8, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26865911

RESUMO

BACKGROUND/OBJECTIVES: Type 2 diabetes (T2D) is more frequently diagnosed and is characterized by hyperglycemia and insulin resistance. D-Xylose, a sucrase inhibitor, may be useful as a functional sugar complement to inhibit increases in blood glucose levels. The objective of this study was to investigate the anti-diabetic effects of D-xylose both in vitro and stretpozotocin (STZ)-nicotinamide (NA)-induced models in vivo. MATERIALS/METHODS: Wistar rats were divided into the following groups: (i) normal control; (ii) diabetic control; (iii) diabetic rats supplemented with a diet where 5% of the total sucrose content in the diet was replaced with D-xylose; and (iv) diabetic rats supplemented with a diet where 10% of the total sucrose content in the diet was replaced with D-xylose. These groups were maintained for two weeks. The effects of D-xylose on blood glucose levels were examined using oral glucose tolerance test, insulin secretion assays, histology of liver and pancreas tissues, and analysis of phosphoenolpyruvate carboxylase (PEPCK) expression in liver tissues of a STZ-NA-induced experimental rat model. Levels of glucose uptake and insulin secretion by differentiated C2C12 muscle cells and INS-1 pancreatic ß-cells were analyzed. RESULTS: In vivo, D-xylose supplementation significantly reduced fasting serum glucose levels (P < 0.05), it slightly reduced the area under the glucose curve, and increased insulin levels compared to the diabetic controls. D-Xylose supplementation enhanced the regeneration of pancreas tissue and improved the arrangement of hepatocytes compared to the diabetic controls. Lower levels of PEPCK were detected in the liver tissues of D-xylose-supplemented rats (P < 0.05). In vitro, both 2-NBDG uptake by C2C12 cells and insulin secretion by INS-1 cells were increased with D-xylose supplementation in a dose-dependent manner compared to treatment with glucose alone. CONCLUSIONS: In this study, D-xylose exerted anti-diabetic effects in vivo by regulating blood glucose levels via regeneration of damaged pancreas and liver tissues and regulation of PEPCK, a key rate-limiting enzyme in the process of gluconeogenesis. In vitro, D-xylose induced the uptake of glucose by muscle cells and the secretion of insulin cells by ß-cells. These mechanistic insights will facilitate the development of highly effective strategy for T2D.

11.
Nutr Res ; 35(7): 626-36, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26088373

RESUMO

D-Xylose, a natural pentose, has been reported to reduce postprandial glucose levels, although its effect on lipid metabolism has not been investigated. Therefore, this study hypothesized that d-xylose, as an alternative sweetener, suppresses adipogenesis and lipid metabolism by regulating blood lipid profiles, blood glucose levels, and related gene expression in high-fat diet (HFD)-induced obese mice. Mice were fed a normal diet, a 60% HFD diet, or an HFD with 5% or 10% of the total sucrose content supplemented with d-xylose (Xylo 5 and Xylo 10 diets, respectively). Weight gain, food intake, and serum lipid levels for each group were measured. After 12 weeks, histopathology of liver sections and assays of gene expression related to adipogenesis and lipid metabolism in visceral fat and liver tissues were analyzed. Body weight gain; fasting blood glucose levels; weights of subcutaneous and visceral adipose tissues; and serum biochemical markers, including total cholesterol and low-density lipoprotein cholesterol, low-/high-density lipoprotein, and total cholesterol/high-density lipoprotein, were significantly lowered in the Xylo 5 and Xylo 10 groups. In addition, d-xylose supplementation resulted in the down-regulation of adipogenesis-related genes, including sterol regulatory element-binding protein 1C, fatty acid synthase, adipocyte protein 2, and CCAAT/enhancer-binding protein α in visceral adipose tissues. Histopathologically, Xylo 5 and Xylo 10 supplementation reduced HFD-induced fat accumulation in the liver and decreased expressions of fatty acid synthase and peroxisome proliferator-activated receptor γ. D-Xylose supplementation also enhanced lipid oxidation by increasing expressions of carnitine palmitoyltransferase 1A; cytochrome P450, family 4, subfamily a, polypeptide 10; and acyl-CoA oxidase. In conclusion, our finding suggests that d-xylose may help prevent or attenuate the progression of obesity-related metabolic disorders by alleviating adipogenesis and dyslipidemia and improving lipid oxidation.


Assuntos
Adipogenia/efeitos dos fármacos , Tecido Adiposo/efeitos dos fármacos , Suplementos Nutricionais , Metabolismo dos Lipídeos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Obesidade , Xilose/farmacologia , Adipogenia/genética , Tecido Adiposo/metabolismo , Animais , Peso Corporal/efeitos dos fármacos , Colesterol/sangue , Dieta Hiperlipídica/efeitos adversos , Regulação para Baixo , Dislipidemias/sangue , Dislipidemias/tratamento farmacológico , Dislipidemias/genética , Dislipidemias/patologia , Metabolismo dos Lipídeos/genética , Lipólise/efeitos dos fármacos , Lipólise/genética , Lipoproteínas/sangue , Fígado/metabolismo , Fígado/patologia , Masculino , Camundongos Endogâmicos C57BL , Camundongos Obesos , Obesidade/sangue , Obesidade/tratamento farmacológico , Obesidade/etiologia , Obesidade/genética , Edulcorantes/farmacologia , Edulcorantes/uso terapêutico , Xilose/uso terapêutico
12.
J Korean Neurosurg Soc ; 56(4): 334-7, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25371784

RESUMO

OBJECTIVE: The purpose of this study is to identify the risk factors associated with the development of germinal matrix-intraventricular hemorrhage (GM-IVH) and the relationship of the severity of disease and prematurity. METHODS: A total of 168 premature neonates whose birth weight ≤1500 g or gestational age ≤34 weeks were examined by cranial ultrasound (CUS) for detection of GM-IVH among the babies admitted between January 2011 and December 2012 in our medical center neonatal intensive care unit. The babies were divided into two groups : GM-IVH and non-IVH. Clinical presentations, precipitating factors of the patients and maternal factors were analyzed. RESULTS: In univariate analysis, gestational age, birth weight, delivery method, presence of premature rupture of membrane (PROM) and level of sodium and glucose were statistically meaningful factors (p<0.05). But only two factors, gestational age and presence of patent ductus arteriosus (PDA) were statistically meaningful in multivariate logistic regression (p<0.05). Delivery method [normal vaginal delivery (NVD) to Caeserean section] was borderline significant (p<0.10). CONCLUSION: Presence of PDA and gestational age were the important risk factors associated with development of GM-IVH.

13.
J Cerebrovasc Endovasc Neurosurg ; 14(3): 186-91, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23210046

RESUMO

OBJECTIVE: The objective of this study is to verify the relationship between subarachnoid hemorrhage (SAH) volume (not Fisher grade) and development of cerebral vasospasm prospectively. METHODS: Patients who visited our hospital with a diffuse or localized thick subarachnoid blood clot seen on computed tomography (CT), taken within 48 hours after SAH and the aneurysm was confirmed by CT Angiogram (CTA) from March 2010 to July 2011 were enrolled in this study. CTA was checked at least twice after admission. Angiographic vasospasm (AVS) on CTA was defined as irregularity or narrowing of intracranial vessels on follow up CTA compared with initial CTA. Total intracranial hemorrhage (ICH) volume (subdural, SAH, intracerebral and intraventricular) was calculated and SAH volume (all supratentorial and infratentorial cisterns) was also calculated using the MIPAV software package. RESULTS: A total of 55 patients were included in our study. Thirty six patients did not show AVS on CTA or clinical deterioration (non vasospasm group: NVS). AVS without ischemic neurologic symptoms was observed in four patients and development of symptomatic vasospasm (SVS), defined as AVS with ischemic symptoms, was observed in 15 patients. SAH volume in SVS patients was statistically larger than that in NVS patients (p < 0.05). Total ICH volume in SVS patients was larger than that in NVS patients. However, the difference was not statistically significant. CONCLUSION: Results of this study indicate an association of development of vasospasm with the SAH volume, not intracranial hemorrhage.

14.
J Korean Neurosurg Soc ; 51(4): 215-8, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22737301

RESUMO

OBJECTIVE: Traumatic epidural hematomas (EDHs) in children are a relatively unusual occurrence. The cause and outcome vary depending on period and region of study. The aims of this analysis were to review the cause and outcome of pediatric EDHs nowadays and to discuss outcome-related variables in a large consecutive series of surgically treated EDH in children. METHODS: This is a retrospective review of 29 patients with surgically treated EDHs between Jan 2000 and February 2010. Patients' medical records, computed tomographic (CT) scans, and, if performed, magnetic resonance imaging (MRI) were reviewed to define variables associated with outcome. Variables included in the analysis were age, associated severe extracranial injury, abnormal pupillary response, hematoma thickness, severity of head injury (Glasgow Coma Scale score), parenchymal brain injury, and diffuse axonal injury. RESULTS: The mean (SD) age of the patients was 109 months (0-185 months). Most of the injuries with EDHs occurred in traffic accident (14 cases, 48.2%) and followed by slip down in 6 cases and falls in 6 cases. There were one birth injury and one unknown cause. EDHs in traffic accidents occurred in pedestrians hit by a motor vehicle, 9 cases; motorbike and car accidents, 5 cases and bicycle accidents, 1 case. The locations of hematoma were almost same in both sides (left side in 15 cases). Temporal lobe is the most common site of hematomas (13 cases, 44%). The mean size of the EDHs was 18 mm (range, 5-40 mm). Heterogeneous hematomas in CT scans were 20 cases (67%). Two patients were referred with unilateral or bilateral dilated pupil(s). There was enlargement of EDH in 5 patients (17%). All of them were heterogeneous hematomas in CT scans. Except for 4 patients, all EDHs were associated with skull fracture(s) (87%). There was no case of patient with major organ injury. CT or MRI revealed brain contusion in 5 patients, and diffuse axonal injury in one patient. The mortality was zero, and the outcomes were excellent in 26 and good in 2 patients. None of the tested variables were found to have a prognostic relevance. CONCLUSION: Regardless of the EDH size, the clinical status of the patients, the abnormal pupillary findings, or the cause of injury, the outcome and prognosis of the patients with EDH were excellent.

15.
Opt Express ; 20(9): 9371-81, 2012 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-22535026

RESUMO

Millimeter wave (MMW) imaging is finding rapid adoption in security applications such as concealed object detection under clothing. A passive MMW imaging system can operate as a stand-off type sensor that scans people in both indoors and outdoors. However, the imaging system often suffers from the diffraction limit and the low signal level. Therefore, suitable intelligent image processing algorithms would be required for automatic detection and recognition of the concealed objects. This paper proposes real-time outdoor concealed-object detection and recognition with a radiometric imaging system. The concealed object region is extracted by the multi-level segmentation. A novel approach is proposed to measure similarity between two binary images. Principal component analysis (PCA) regularizes the shape in terms of translation and rotation. A geometric-based feature vector is composed of shape descriptors, which can achieve scale and orientation-invariant and distortion-tolerant property. Class is decided by minimum Euclidean distance between normalized feature vectors. Experiments confirm that the proposed methods provide fast and reliable recognition of the concealed object carried by a moving human subject.


Assuntos
Interpretação de Imagem Assistida por Computador/instrumentação , Interpretação de Imagem Assistida por Computador/métodos , Reconhecimento Automatizado de Padrão/métodos , Radar/instrumentação , Imagem Corporal Total/instrumentação , Imagem Corporal Total/métodos , Desenho de Equipamento , Análise de Falha de Equipamento , Micro-Ondas
16.
Biosci Biotechnol Biochem ; 75(3): 434-42, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21389625

RESUMO

The protective effects of decursin (D) and decursinol angelate (DA) purified from Angelica gigas Nakai on amyloid ß-protein (Aß)-induced neurotoxicity and the underlying mechanisms were investigated. Aß plays a major role in the pathogenesis of Alzheimer's disease (AD) by eliciting oxidative stress. It significantly increased cytotoxicity and lipid peroxidation, but decreased glutathione contents and antioxidant enzyme activities. All of these results were markedly reversed by pretreatment with D or DA. Nuclear transcription factor Nrf2, which regulates the expression of antioxidant enzymes, was significantly increased by D or DA pretreatment. Furthermore, D and DA suppressed Aß aggregation. These results suggest that D and DA increase cellular resistance to Aß-induced oxidative injury in the rat pheochromocytoma (PC12) cells, presumably through not only the induction of Nrf2 and related antioxidant enzymes, but also the anti-aggregation of Aß. Thus D and DA have therapeutic potential in treating AD and other oxidative stress-related diseases.


Assuntos
Peptídeos beta-Amiloides/toxicidade , Antioxidantes/farmacologia , Benzopiranos/farmacologia , Butiratos/farmacologia , Fator 2 Relacionado a NF-E2/metabolismo , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/fisiopatologia , Angelica/química , Animais , Western Blotting , Catalase/genética , Catalase/metabolismo , Sobrevivência Celular , Relação Dose-Resposta a Droga , Expressão Gênica/efeitos dos fármacos , Glutationa/metabolismo , Glutationa Peroxidase/genética , Glutationa Peroxidase/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Fator 2 Relacionado a NF-E2/genética , Oxirredução/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Células PC12 , Ratos , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo
17.
Opt Express ; 19(3): 2530-6, 2011 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-21369072

RESUMO

Millimeter wave imaging is finding rapid adoption in security applications such as the detection of objects concealed under clothing. A passive imaging system can be realized as a stand-off type sensor that can operate in open spaces, both indoors and outdoors. In this paper, we address real-time outdoor concealed-object detection and segmentation with a radiometric imaging system operating in the W-band. The imaging system is equipped with a dielectric lens and a receiver array operating at around 94 GHz. Images are analyzed by multilevel segmentation to identify a concealed object. Each level of segmentation comprises vector quantization, expectation-maximization, and Bayesian decision making to cluster pixels on the basis of a Gaussian mixture model. In addition, we describe a faster process that adopts only vector quantization for the first level segmentation. Experiments confirm that the proposed methods provide fast and reliable detection and segmentation for a moving human subject carrying a concealed gun.


Assuntos
Monitoramento Ambiental/instrumentação , Aumento da Imagem/instrumentação , Interpretação de Imagem Assistida por Computador/instrumentação , Micro-Ondas , Sistemas Computacionais , Desenho de Equipamento , Análise de Falha de Equipamento
18.
J Clin Ultrasound ; 39(2): 111-3, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20848573

RESUMO

Nicolau syndrome (also known as embolia cutis medicamentosa and livedoid dermatitis) is a rare but severe localized adverse drug reaction of intramuscular injection of various drugs. The typical presentation is pain around the injection site soon after injection, followed by erythema, livedoid patch, hemorrhagic patch, and finally necrosis of skin, subcutaneous fat, and muscle tissue. We report a case that occurred in a 34-year-old woman after intramuscular injection of diclofenac sodium. Sonography showed diffuse thickening with increased echogenicity of the skin and subcutaneous fat layer, while MRI revealed extensive edema involving gluteal and piriformis muscles and deep fascia, and fluid collection.


Assuntos
Anti-Inflamatórios não Esteroides/efeitos adversos , Diclofenaco/efeitos adversos , Toxidermias/diagnóstico por imagem , Toxidermias/etiologia , Injeções Intramusculares/efeitos adversos , Adulto , Anti-Inflamatórios não Esteroides/administração & dosagem , Nádegas , Diclofenaco/administração & dosagem , Toxidermias/diagnóstico , Feminino , Humanos , Imageamento por Ressonância Magnética , Pele/diagnóstico por imagem , Pele/patologia , Gordura Subcutânea/diagnóstico por imagem , Gordura Subcutânea/patologia , Ultrassonografia
19.
J Ethnopharmacol ; 132(1): 328-33, 2010 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-20736054

RESUMO

AIM OF THE STUDY: Poncirus fructus (PF)--also known as the dried, immature fruit of Poncirus trifoliata (L.) Raf. (Rutaceae)--is a natural substance that has long been used for various gastrointestinal disorders in eastern Asia. An aqueous extract of PF (PF-W) has particularly potent gastroprokinetic effects, but its molecular mechanism was not well understood. Identification of the underlying prokinetic mechanism of PF-W was pursued in the present study. MATERIALS AND METHODS: Changes in in vitro cAMP levels and in vivo intestinal transit rate (ITR) caused by PF-W were measured after pretreatment with GR125487, an antagonist for serotonin receptor subtype 4 (5-HT4R). An [(3)H] astemizole binding assay and electrophysiology experiments were performed to determine if PF-W has any interaction with the human ether-à-go-go related gene (hERG) potassium channel. RESULTS: PF-W induced an increase in intracellular cAMP in 5-HT4R-expressing HEK293T cells, indicating that PF-W does activate 5-HT4R. Moreover, pretreatment with GR125487 successfully blocked the increase, suggesting that the response was 5-HT4R-specific. More importantly, pretreatment of GR125487 in rats inhibited the elevation of ITR by PF-W, indicating that the prokinetic effect of PF-W was indeed exerted via 5-HT4R. On the other hand, both [(3)H]-astemizole binding assay and electrophysiological experiments revealed that PF-W did not interfere at all with the hERG channel. CONCLUSION: It was found that PF-W exerts its prokinetic activity through a 5-HT4R-mediated pathway, with no interaction with hERG channels. Therefore, PF-W is a good candidate that might be developed as a prokinetic agent with fewer expected cardiac side effects.


Assuntos
Canais de Potássio Éter-A-Go-Go/metabolismo , Trânsito Gastrointestinal/efeitos dos fármacos , Extratos Vegetais/farmacologia , Poncirus/química , Receptores 5-HT4 de Serotonina/metabolismo , Agonistas do Receptor 5-HT4 de Serotonina/farmacologia , Animais , Astemizol/farmacologia , Linhagem Celular , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , AMP Cíclico/metabolismo , Canal de Potássio ERG1 , Canais de Potássio Éter-A-Go-Go/genética , Frutas/química , Humanos , Técnicas de Patch-Clamp , Extratos Vegetais/efeitos adversos , Extratos Vegetais/isolamento & purificação , Bloqueadores dos Canais de Potássio/farmacologia , Ligação Proteica , Ratos , Ratos Sprague-Dawley , Receptores 5-HT4 de Serotonina/genética , Agonistas do Receptor 5-HT4 de Serotonina/efeitos adversos , Agonistas do Receptor 5-HT4 de Serotonina/isolamento & purificação , Antagonistas do Receptor 5-HT4 de Serotonina/farmacologia , Transfecção
20.
J Ind Microbiol Biotechnol ; 36(12): 1467-71, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19756800

RESUMO

An immunosuppressant tacrolimus-producing strain of Streptomyces sp. TST8 was isolated and developed by the TS corporation in Korea using the sequential adaptation of media containing tacrolimus (600-1600 mg/l). The aim of the tacrolimus sequential adaptation protocol was to select those cells with tacrolimus resistance and to reduce product inhibition of the tacrolimus-producing strain. The developed strains produced more tacrolimus than the original strain. In particular, the TST10 strain adapted in the medium containing 900 mg/l of tacrolimus produced 972 mg/l of tacrolimus in the final titer after 7 days of cultivation in a 5-l jar fermenter. This is the largest final titer of tacrolimus produced by a specific strain to date. Because the sequential adaptation protocol is limited by the solubility of tacrolimus in water, the final tacrolimus titer of TST11 adapted in the medium containing 1600 mg/l of tacrolimus was lower than that of TST10. The developed strains and the development method using sequential adaptation can facilitate the efficient and economical production of tacrolimus.


Assuntos
Imunossupressores/metabolismo , Microbiologia Industrial , Streptomyces/isolamento & purificação , Tacrolimo/metabolismo , Adaptação Fisiológica , Meios de Cultura , Farmacorresistência Bacteriana , Fermentação , Coreia (Geográfico) , Testes de Sensibilidade Microbiana , Streptomyces/classificação , Streptomyces/genética , Streptomyces/fisiologia
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