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Diabetic nephropathy (DN) represents a major diabetes-related complication, which could undermine renal function. CircCOL1A2 has been previously reported to show abnormal expression during DN. However, its functional role in the progression of DN, as well as the potential molecular mechanisms, remains unclear. The present work examined the expression of circCOL1A2 in the plasma of DN patients, and employed high glucose (HG)-challenged HK-2 cells as the in vitro cell model of hyperglycemia (HG)-induced DN. CircCOL1A2 was silenced using siRNA in HK-2 cells to clarify the functional engagement of circCOL1A2 in HG-induced DN. We examined the roles of circCOL1A2 in regulating oxidative stress by measuring reactive oxygen species (ROS), lipid peroxidation, and superoxide dismutase (SOD) levels. Besides, the effects of circCOL1A2 silencing on pyroptosis were investigated by RT-qPCR, western blot (WB), and ELISA assays. StarBase (version 2.0) was used to identify the downstream effector of circCOL1A2, and their interactions were further verified through dual-luciferase reporter analysis, RNA pull-down assays, and RNA immunoprecipitation (RIP) assay. CircCOL1A2 was highly expressed in DN patients and HG-induced HK-2 cells. Knocking down circCOL1A2 alleviated oxidative stress and pyroptosis upon HG treatment. In addition, we demonstrated that circCOL1A2 knockdown could promote miR-424-5p expression while inhibiting Serum/Glucocorticoid Regulated Kinase 1 (SGK1) level. Furthermore, miR-424-5p inhibitor or SGK1 overexpression impaired the effects of circCOL1A2 knockdown on HG-induced oxidative stress and pyroptosis. Hence, our results demonstrated that the circCOL1A2 mediates HG-exposed pyroptosis and oxidative stress through modulating miR-424-5p/SGK1 axis in diabetic nephropathy, indicating that silencing circCOL1A2 is a potential intervention strategy for DN management.
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Diabetes Mellitus , Nefropatias Diabéticas , MicroRNAs , Humanos , Colágeno Tipo I , Nefropatias Diabéticas/genética , Glucocorticoides , Glucose/toxicidade , MicroRNAs/genética , Estresse Oxidativo , Piroptose/genética , RNA Circular/genéticaRESUMO
The aim of this study was to identify the antimicrobial effect and mechanism of whey protein and blueberry juice mixed systems fermented with Lactobacillus against Escherichia coli during storage. The whey protein and blueberry juice mixed systems were fermented with L. casei M54, L. plantarum 67, S. thermophiles 99 and L. bulgaricus 134 and had different antibacterial activities against E. coli during storage. The antimicrobial activity of the mixed whey protein and blueberry juice mixture systems was the highest, with an inhibition zone diameter of approximately 230 mm, compared with the whey protein or blueberry juice systems alone. There were no viable E. coli cells 7 h after treatment with of the whey protein and blueberry juice mixed systems as determined by survival curve analysis. Analysis of the inhibitory mechanism showed that the release of alkaline phosphatase, electrical conductivity, protein and pyruvic acid contents, and aspartic acid transaminase and alanine aminotransferase activity in E. coli increased. These results demonstrated that these mixed systems fermented with Lactobacillus, especially those containing blueberries, could inhibit the growth of E. coli and even cause cell death by destroying the cell membrane and cell wall.
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Anti-Infecciosos , Mirtilos Azuis (Planta) , Lactobacillus plantarum , Lactobacillus/metabolismo , Proteínas do Soro do Leite/metabolismo , Mirtilos Azuis (Planta)/metabolismo , Escherichia coli/metabolismo , Lactobacillus plantarum/metabolismo , Anti-Infecciosos/metabolismo , FermentaçãoRESUMO
BACKGROUND AND PURPOSE: If the preoperative pathological information is inadequate, a risk classification may not be able to be determined for some patients with neuroblastoma. Our objectives were to include imaging factors, serum biomarkers, and demographic factors in a nomogram to distinguish high-risk patients before surgical resection based on the COG classification. METHOD: A total of 106 patients were included in the study. Of these, patients with clinicopathologically confirmed neuroblastoma at Tianjin Children's Hospital from January 2013 to November 2021 formed the training cohort (n = 82) for nomogram development, and those patients from January 2010 to December 2013 formed the validation cohort (n = 24) to confirm the model's performance. RESULT: On multivariate analysis of the primary cohort, independent factors for high risk were the presence of distant metastasis (p = 0.004), lactate dehydrogenase (LDH) (p = 0.009), and tumor volume (p = 0.033), which were all selected into the nomogram. The calibration curve for probability showed good agreement between prediction by nomogram and actual observation. The C-index of the nomogram was 0.95 95% [0.916-0.99]. Application of the nomogram in the validation cohort still gave good discrimination and good calibration. CONCLUSION: Three independent factors including the presence of distant metastasis, lactate dehydrogenase (LDH), and tumor volume are associated with high-risk neuroblastoma and selected into the nomogram. The novel nomogram has the flexibility to apply a clinically suitable cutoff to identify high-risk neuroblastoma patients despite inadequate preoperative pathological information. The nomogram can allow these patients to be offered suitable induction chemotherapy regimens and surgical plans. LEVELS OF EVIDENCE: Level III.
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Neuroblastoma , Nomogramas , Criança , Humanos , Biópsia/normas , Lactato Desidrogenases , Neuroblastoma/patologia , Neuroblastoma/cirurgia , Risco , Medição de RiscoRESUMO
Early identification of individuals with mild cognitive impairment (MCI) is essential to combat worldwide dementia threats. Physical function indicators might be low-cost early markers for cognitive decline. To establish an early identification tool for MCI by combining physical function indicators (upper and lower limb function) via a clinical prediction modeling strategy. A total of 5393 participants aged 60 or older were included in the model. The variables selected for the model included sociodemographic characteristics, behavioral factors, mental status and chronic conditions, upper limb function (handgrip strength), and lower limb function (self-rated squat ability). Two models were developed to test the predictive value of handgrip strength (Model 1) or self-rated squat ability (Model 2) separately, and Model 3 was developed by combining handgrip strength and self-rated squat ability. The 3 models all yielded good discrimination performance (area under the curve values ranged from 0.719 to 0.732). The estimated net reclassification improvement values were 0.3279 and 0.1862 in Model 3 when comparing Model 3 to Model 1 and Model 2, respectively. The integrated discrimination improvement values were estimated as 0.0139 and 0.0128 when comparing Model 3 with Model 1 and Model 2, respectively. The model that contains both upper and lower limb function has better performance in predicting MCI. The final prediction model is expected to assist health workers in early identification of MCI, thus supporting early interventions to reduce future risk of AD, particularly in socioeconomically deprived communities.
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Doença de Alzheimer , Disfunção Cognitiva , Humanos , Força da Mão , Disfunção Cognitiva/diagnóstico , Medição de RiscoRESUMO
In this study, enzymatic cross-linked whey protein coupling ultrafiltration was used to reduce membrane fouling and increase whey protein recovery rate. The filtration efficiency and protein interaction with the membrane surface were investigated. The results showed that the protein recovery rate and relative flux of transglutaminase catalysis protein followed by tyrosinase each increased by approximately 30% during ultrafiltration. The total membrane resistance was reduced by approximately 20%. The shape of the transglutaminase and tyrosinase cross-linked protein had somewhat spherical and cylindrical structure similar to an elongated shape based on fluorescence microscopy imaging, which indicated membrane resistance reduction. Fluorescence excitation-emission matrix spectroscopy (EEM) showed that the permeation peak intensities of transglutaminase followed by tyrosinase catalysis protein decreased sharply in the tryptophan and aromatic-like protein fields, indicating that most protein was rejected after ultrafiltration. The repulsive interaction energy was increased between the cross-linked proteins and membrane based on extended Derjaguin-Landau-Verwey-Overbeek (XDLVO) analysis.
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INTRODUCTION: CD30+ primary cutaneous anaplastic large cell lymphoma (PC-ALCL) is a rare T-cell neoplasm, and has been reported to present with an indolent behavior. The PC-ALCL with aggressive behavior has not been reported in the literature. PATIENT CONCERNS: We treated a patient with PC-ALCL that exhibited indolent behavior in the past 2âyears and aggressive behavior within the last 3âmonths before presentation. DIAGNOSIS: Aggressive CD30+ primary cutaneous anaplastic large cell lymphoma. INTERVENTIONS: The radiotherapy regimen was individualized in terms of the target volume delineation and dose prescription, and the dose-response relationship was evaluated. OUTCOMES: The mean distance of microscopic infiltration was 14.1âmm in depth and 14.3âmm circumferentially. The lesion completely regressed after the delivery of 40âGy in 20 fractions over 4âweeks. The tumor did not recur over the next year. CONCLUSION: An aggressive disease course is rare for indolent CD30+ PC-ALCL, which has similar histopathological characteristics as indolent PC-ALCL. The radiotherapy strategy should be individualized with curative intent.
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Fracionamento da Dose de Radiação , Linfoma Anaplásico Cutâneo Primário de Células Grandes/radioterapia , Neoplasias Cutâneas/radioterapia , Pele/patologia , Idoso de 80 Anos ou mais , Humanos , Linfoma Anaplásico Cutâneo Primário de Células Grandes/diagnóstico , Linfoma Anaplásico Cutâneo Primário de Células Grandes/patologia , Imageamento por Ressonância Magnética , Masculino , Estadiamento de Neoplasias , Dosagem Radioterapêutica , Pele/diagnóstico por imagem , Neoplasias Cutâneas/diagnóstico , Neoplasias Cutâneas/patologia , Tomografia Computadorizada por Raios X , Resultado do TratamentoRESUMO
This study aimed to determine the effect of initial pH and temperature on whey protein gel formation via the Maillard reaction, including changes in gel structure, rheological and texture properties. The color changes in the whey protein and glucose gels were not significant with increasing heat temperature. High temperature and alkaline conditions promoted exposure to hydrophobic groups such as -SH, which accelerated protein aggregation and gel formation. Moreover, the increased particle size and additional hydrophobic groups contributed to higher elastic modulus (G') in the whey protein gel. Fluorescence measurements revealed that more tryptophan on the protein surface decreased with increasing temperature, which indicated that exposure to tryptophan could increase the hydrophobicity of the protein gels. Whey proteins formed stronger, gummier, more elastic, and more cohesive gels at 70 â under initial pH 9 conditions, which also increased with the addition of fructose.
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Géis/química , Glucose/química , Reação de Maillard , Temperatura , Proteínas do Soro do Leite/química , Carboidratos , Temperatura Alta , Concentração de Íons de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Reologia , SensaçãoRESUMO
This study aimed to improve the stability of the anthocyanins and phenolic acids of blueberry by forming hydrogen bonds or hydrophobic interactions with whey protein using lactic acid fermentation. The effects of the initial pH on the characteristics of the whey protein and blueberry juice system fermented using Lactobacillus plantarum and Lactobacillus casei were investigated. The color and total phenol and anthocyanin contents of the blueberry juice and whey protein system became stable after fermentation using Lactobacillus plantarum and Lactobacillus casei. Fluorescence measurements and Fourier transform infrared spectroscopy (FTIR) analysis reveal that the characteristics of whey protein and blueberry juice changed significantly after fermentation using Lactobacillus plantarum and Lactobacillus casei indicating the binding of anthocyanins or phenolic hydroxyl groups of blueberry to N-H, C-N and C[double bond, length as m-dash]O groups of whey protein. The α-helix content of whey protein and blueberry fermented using Lactobacillus plantarum alone decreased by 18% and ß-sheet content increased by approximately 27% compared to whey protein fermented using Lactobacillus plantarum.
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Phytoremediation technology has been applied for heavy metal elimination for many years, however little research about the difference of remediation efficiency of hyperaccumulator in different soils was reported. Here, a pot experiment was conducted with a cadmium (Cd)/zinc hyperaccumulator Sedum alfredii Hance grown on different types of soils and the differences of its endophytic bacterial community were elucidated. The results showed that the biomass of S. alfredii grown on black soil under both low and high Cd treatment was much heavier than that grown on other soils, and Cd uptake and Cd accumulation of S. alfredii in paddy soil was the highest, suggesting that black soil was more suitable for S. alfredii growth while paddy soil was more efficient for Cd phytoextraction. Moreover, Cd treated level and soil type both affected the structure of plant endophytic bacterial community. The two shared genera in the four representative soils were Caulobacter and Acinetobacter under low Cd level, and Caulobacter and Lactobacillus under high Cd level. Cd treatment shifted the structure and abundance of plant endophytes in different types of soils, while black soil and paddy soil were more similar in the distribution and abundance of S. alfredii endophytic community. This study highlighted the understanding of response to Cd within S. alfredii endophytic community in different types of soils, which could be beneficial for enhanced phytoremediation efficiency and better S. alfredii cultivation.
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Sedum , Poluentes do Solo , Biodegradação Ambiental , Cádmio/análise , Raízes de Plantas/química , Solo , Poluentes do Solo/análiseRESUMO
Whey is a byproduct with nutritional value and high organic and saline content. It is an important source of organic contamination in dairy industry. In this paper, we gave an overview of the current use of membrane materials and membrane processing in cheese whey protein recovery and discussed recent developments in membrane technology. Different types of membranes, such as polymers, ceramic membranes and modification membranes, are used for various purposes, such an increasing permeation flux, reducing membrane fouling, and increasing the protein rejection rate, concentration, fractionation and purification of whey protein. New membrane processing methods and integrated membrane methods to recover whey protein were reviewed. Membrane fouling factors during whey protein ultrafiltration process, which included whey protein conformation, membrane filtration conditions and the interaction between proteins and the membrane surface or pores, were also discussed and analyzed to reveal membrane fouling mechanism.
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Manipulação de Alimentos/instrumentação , Manipulação de Alimentos/métodos , Membranas Artificiais , Proteínas do Soro do Leite/isolamento & purificação , Queijo/análise , Indústria de Laticínios/métodos , Poluição Ambiental/prevenção & controle , Contaminação de Alimentos , Resíduos Industriais/prevenção & controle , Polímeros , Ultrafiltração/métodos , Purificação da Água , Soro do LeiteRESUMO
The process of microbial transglutaminase (TG) covalent immobilization on an ultrafiltration membrane surface, the optimum immobilization conditions and the characteristics of the enzymatic membrane in a reactor were investigated. The process of TG immobilization on polyethersulfone (PES) membrane surfaces was analyzed by Fourier transform infrared and X-ray photoelectron spectroscopy. The optimal condition for TG immobilization was in pH 5.0 phosphate buffer containing TG (20 U/mL). The immobilized TG had a high affinity for the substrate according to the kinetic parameters and retained 50% activity until the twentieth day. Water contact angle and antifouling tests showed that the hydrophilicity of immobilized-transglutaminase membrane was improved compared with pure PES membrane. The enzyme could maintain relatively high activity under a transmembrane pressure of 0.15 MPa. Moreover, the enzymatic membrane had higher relative membrane flux at 0.15 MPa in a membrane reactor, and could retain its activity in pH 5.0 phosphate buffer and catalysis under 40 °C.
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Reatores Biológicos , Enzimas Imobilizadas/metabolismo , Membranas Artificiais , Polímeros/química , Sulfonas/química , Transglutaminases/metabolismo , Enzimas Imobilizadas/química , Interações Hidrofóbicas e Hidrofílicas , Transglutaminases/química , Ultrafiltração/instrumentaçãoRESUMO
Precartilaginous stem cells (PSCs) are adult stem cells which could self-renew or differentiate into chondrocytes to promote bone growth. In this study, we aimed to understand the role of transforming growth factor-ß1 (TGF-ß1) in precartilaginous stem cell (PSC) differentiation and to study the mechanisms that underlie this role. We purified PSCs from the neonatal murine perichondrial mesenchyme using immunomagnetic beads, and primary cultured them. Their phenotype was confirmed by the PSC marker fibroblast growth factor receptor-3 (FGFR-3) overexpression. TGF-ß1 was added to induce PSCs differentiation. TGF-ß1 increased mRNA expression of chondrogenesis-related genes (collagen type II, Sox 9 and aggrecan) in the cultured PSCs. This was abolished by TGF-ß receptor II (TGFRII) and Casein kinase 1 epsilon (CK1ε) lentiviral shRNA depletion. Meanwhile, we found that TGF-ß1 induced CK1ε activation, glycogen synthase kinase-3ß (GSK3ß) phosphorylation and ß-catenin nuclear translocation in the mouse PSCs, which was almost completely blocked by TGFRII and CK1ε shRNA knockdown. Based on these results, we suggest that TGF-ß1 induces CK1ε activation to promote ß-catenin nuclear accumulation, which then regulates chondrogenesis-related gene transcription to eventually promote mouse PSC differentiation.
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Células-Tronco Adultas/efeitos dos fármacos , Caseína Quinase 1 épsilon/metabolismo , Diferenciação Celular/efeitos dos fármacos , Condrócitos/efeitos dos fármacos , Condrogênese/efeitos dos fármacos , Receptor do Fator de Crescimento Transformador beta Tipo II/agonistas , Fator de Crescimento Transformador beta1/farmacologia , beta Catenina/metabolismo , Células-Tronco Adultas/enzimologia , Agrecanas/genética , Agrecanas/metabolismo , Animais , Animais Recém-Nascidos , Caseína Quinase 1 épsilon/genética , Diferenciação Celular/genética , Células Cultivadas , Condrócitos/enzimologia , Condrogênese/genética , Colágeno Tipo II/genética , Colágeno Tipo II/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Glicogênio Sintase Quinase 3 beta/metabolismo , Camundongos Endogâmicos C57BL , Técnicas de Transferência Nuclear , Fenótipo , Fosforilação , Receptor Tipo 3 de Fator de Crescimento de Fibroblastos/genética , Receptor Tipo 3 de Fator de Crescimento de Fibroblastos/metabolismo , Receptor do Fator de Crescimento Transformador beta Tipo II/genética , Receptor do Fator de Crescimento Transformador beta Tipo II/metabolismo , Fatores de Transcrição SOX9/genética , Fatores de Transcrição SOX9/metabolismo , Transdução de Sinais/efeitos dos fármacosRESUMO
Early diagnosis and changes associated with atherosclerosis are crucial in clinical medicine. However, atherosclerosis is a multifactorial disease. Asiaticoside (AA), a triterpenoid derived from Centella asiatica, has anti-inflammatory activity. Endothelium-derived nitric oxide is important in modulating vascular tone in a distinct vessel size-dependent manner; it plays a dominant role in conduit arteries and endothelium-dependent hyperpolarisation in resistance vessels. This study evaluated the effects of AA administration on human umbilical endothelial cells with oxidised low-density lipoprotein-induced inflammation. We measured the levels of intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1). Our results indicated that 10-30 µM AA modulated endothelial hyper permeability, adenosine triphosphate levels, ICAM-1 expression, VCAM-1 expression, E-selectin levels, and PECAM-1 expression to 90% (p < 0.005), 80% (p < 0.05), 105% (p < 0.01), 65% (p < 0.005), 70% (p < 0.05), and 105% (p < 0.01), respectively. Taken together, our data suggest that AA inhibits the augmentation of endothelial permeability, thus preventing the early events of atherosclerosis.
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In whey ultrafiltration (UF) production, two main problems are whey protein recovery and membrane fouling. In this study, membrane coupling protein transglutaminase (TG) catalysis protein cross-linking was investigated under different conditions to find out the best treatment. We found that the optimal conditions for protein recovery involved catalyzing whey protein cross-linking with TG (40U/g whey proteins) at 40°C for 60min at pH 5.0. Under these conditions, the recovery rate was increased 15-20%, lactose rejection rate was decreased by 10%, and relative permeate flux was increase 30-40% compared to the sample without enzyme treatment (control). It was noticeable that the total resistance and cake resistance were decreased after enzyme catalysis. This was mainly due to the increased particle size and decreased zeta potential. Therefore, membrane coupling enzyme catalysis protein cross-linking is a potential means for further use.
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Queijo/análise , Transglutaminases/metabolismo , Ultrafiltração/métodos , Proteínas do Soro do Leite/química , Reagentes de Ligações CruzadasRESUMO
ETHNOPHARMACOLOGICAL RELEVANCE: It is vital for astronauts to develop effective countermeasures to prevent their decline of cognitive performance in microgravity to make space-flight missions successful. The traditional Chinese herbal formula Kai Xin San (KXS) has been used to treat amnesia for thousands years. It is a traditional complex prescription comprising of ginseng (Panax ginseng C. A. Meyer), hoelen (Poria cocos (Schw.) Wolf), polygala (Polygala tenaifolia Willd), and acorus (Acorus tatarinowii Schott). Previous study showed KXS could improve CMS-induced memory impairment in rats. MATERIAL AND METHODS: In this paper, a unique environmental factor-microgravity (weightlessness) was simulated as hindlimb suspension (HLS) by tail in rats for two weeks as the HLS animal model. The KXS at the doses of 0.3 or 0.6g/kg p.o. daily was administrated to HLS rats for two weeks at the same time of HLS, the memory behavior tests were investigated with Morris water maze (MWM) and Shuttle Box (SB) test. The levels of ROS, 8-OHdG and 3-nitrotyrosine (3-NT) in the serum, and AChE and ChAT activity in the brain of rats were determined by ELISA or biochemical analysis. RESULTS: After HLS for two weeks, the escape latency and the swimming distance were significantly increased in the MWM test in rats in the HLS group, compared with control group. The percent of swimming distance in target quadrant and the number of target crossing was significantly decreased in rats in the HLS group compared with the control group. Performance in the SB test showed, the numbers and the distance of active avoidance was decreased from day 4 to day 7, the time spent in electric area was increased in rats in the HLS group compared with the control group. Administration of KXS 0.3 or 0.6g/kg to the HLS rats for two weeks significantly reduced the escape latency and the swimming distance, increased the percentage of swimming distance in target quadrant and the number of target crossings (P<0.01, compared with the HLS group) in the MWM test. Similar treatment with KXS increased the numbers and the distance of active avoidance (P<0.01, compared with the HLS group) and reduced the time spent in electric area after training 3 days in the SB test (P<0.01, compared with the HLS group). The HLS induced the increase of the ROS, 8-OHdG and 3-NT in the serum of rats, but has little influence on the AChE, ChAT activity in the brain. Only the AChE activity in the cortex and the ChAT activity in the hippocampus had some changes in rats in the HLS model group. After administration of KXS 0.6g/kg for two weeks, the abnormal levels of ROS, 8-OHdG, 3-NT were found reversed in the serum of rats (P<0.05, compared with HLS model group). And KXS 0.3g/kg was found reversed the increased AChE activity in the cortex. CONCLUSIONS: Experimental results from this study show that KXS may improve memory deficiency induced by HLS, its mechanisms are major related to antioxidant activities, rather than the central cholinergic system.
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Transtornos Cognitivos/tratamento farmacológico , Medicamentos de Ervas Chinesas/uso terapêutico , Fármacos Neuroprotetores/uso terapêutico , Ausência de Peso/efeitos adversos , 8-Hidroxi-2'-Desoxiguanosina , Acetilcolinesterase/metabolismo , Animais , Aprendizagem da Esquiva/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Colina O-Acetiltransferase/metabolismo , Transtornos Cognitivos/sangue , Transtornos Cognitivos/metabolismo , Desoxiguanosina/análogos & derivados , Desoxiguanosina/sangue , Modelos Animais de Doenças , Medicamentos de Ervas Chinesas/farmacologia , Reação de Fuga/efeitos dos fármacos , Elevação dos Membros Posteriores , Masculino , Memória/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Fitoterapia , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/sangue , Natação , Tirosina/análogos & derivados , Tirosina/sangueRESUMO
9α-hydroxy-4-androstene-3,17-dione (9-OH-AD) is an important intermediate in the steroidal drugs production. 3-ketosteroid-9α-hydroxylase (KSH), a two protein system of KshA and KshB, is a key-enzyme in the microbial steroid ring B-opening pathway. KSH catalyzes the transformation of 4-androstene-3,17-dione (AD) into 9-OH-AD specifically. In the present study, the putative KshA and KshB genes were cloned from Mycobacterium smegmatis mc(2)155 and Gordonia neofelifaecis NRRL B-59395 respectively, and were inserted into the expression vector pNIT, the co-expression plasmids of kshA-kshB were obtained and electroporated into Mycobacterium sp. NRRL B-3805 cells. The recombinants were used to transform steroids, the main product was characterized as 9α-hydroxy-4-androstene-3,17-dione (9-OH-AD), showing that kshA and kshB were expressed successfully. Different from the original strain Mycobacterium sp. NRRL B-3805 that accumulates 4-androstene-3,17-dione, the recombinants accumulates 9α-hydroxy-4-androstene-3,17-dione as the main product. This results indicates that the putative genes kshA, kshB encode active KshA and KshB, respectively. The process of biotransformation was investigated and the results show that phytosterol is the most suitable substrate for biotransformation, kshA and kshB from M. smegmatis mc(2)155 seemed to exhibit high activity, because the resultant recombinant of them catalyzed the biotransformation of phytosterol to 9-OH-AD in a percent conversion of 90%, which was much higher than that of G. neofelifaecis NRRL B-59395. This study on the manipulation of the ksh genes in Mycobacterium sp. NRRL B-3805 provides a new pathway for producing steroid medicines.
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Androstenodiona/análogos & derivados , Proteínas de Bactérias/metabolismo , Oxigenases de Função Mista/metabolismo , Mycobacterium/metabolismo , Androstenodiona/biossíntese , Proteínas de Bactérias/genética , Biotransformação , Cetosteroides , Oxigenases de Função Mista/genética , Mycobacterium smegmatis/enzimologia , PlasmídeosRESUMO
Bone-burring is a common procedure in orthopedic, dental, and otologic surgeries. Virtual reality (VR)-based surgical simulations with both visual and haptic feedbacks provide novice surgeons with a feasible and safe way to practice their burring skill. However, creating realistic haptic interactions between a high-speed rotary burr and stiff bone is a challenging task. In this paper, we propose a novel interactive haptic bone-burring model based on impulse-based dynamics to simulate the contact forces, including resistant and frictional forces. In order to mimic the lateral and axial burring vibration forces, a 3D vibration model has been developed. A prototype haptic simulation system for the bone-burring procedure has been implemented to evaluate the proposed haptic rendering methods. Several experiments of force evaluations and task-oriented tests were conducted on the prototype system. The results demonstrate the validity and feasibility of the proposed methods.
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The present study aims to test two different doses of aqueous extract of black maca on learning and memory in ovariectomized (OVX) mice and their relation with malonalehyde (MDA), acetylcholinesterase (Ache) and monoamine oxidase (MAO) brain levels. Female mice were divided into five groups: (i) naive (control), (ii) sham, (iii) OVX mice and OVX mice treated with (iv) 0.50 g kg(-1) and (v) 2.00 g kg(-1) black maca. Mice were orally treated with distilled water or black maca during 35 days starting 7 days after surgery. Memory and learning were assessed using the water Morris maze (from day 23-27) and the step-down avoidance test (days 34 and 35). At the end of each treatment, mice were sacrificed by decapitation and brains were dissected out for MDA, Ache and MAO determinations. Black maca (0.5 and 2.0 g/kg) increased step-down latency when compared to OVX control mice. Black maca decreased MDA and Ache levels in OVX mice; whereas, no differences were observed in MAO levels. Finally, black maca improved experimental memory impairment induced by ovariectomy, due in part, by its antioxidant and Ache inhibitory activities.
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A new 8-O-4' neolignan glycoside was isolated from the stem bark of Tetracentron sinense. Its structure was elucidated as erythro 4',5',7, 9, 9'-pentahydroxy-3-methoxy 8-O-4'-neolignan 3'-O-beta-glucopyranoside on the basis of spectral evidence (MS, IR, 1D and 2D NMR).