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Oral administration of S-nitroso-N-acetylcysteine prevents the onset of non alcoholic fatty liver disease in rats

World Journal of Gastroenterology 2006年第12期12卷 1905-1911页

作者： Claudia PMS de Oliveira Fernanda I Simplicio Vicencia MR de Lima Katia Yuahasi Fabio P Lopasso Venancio AF Alves dulcinéia SP abdalla Flair J Carrilho Francisco RM Laurindo Marcelo G de Oliveira University of Sāo Paulo School of Medicine Department of Gastroenterology Saoo Paulo SP Brazil School of Medicine Department of Pathology Sāo Paulo SP Brazil University of So Paulo Medical School Heart Institute InCor Sāo Paulo SP Brazil University of Sāo Paulo School of Pharmaceutical Sciences Department of Clinical and Toxicological Analysis Sao Paulo SP Brazil State University of CamDinas. Chemistry Department. Campinas. SE Brazil

AIM： To evaluate the potential of S-nitroso-N-acetylcysteine （SNAC） in inhibition of lipid peroxidation and the effect of oral SNAC administration in the prevention of nonalcoholic fatty liver disease （NAFLD） in an animal model.METHODS： NAFLD was induced in Wistar male rats by choline-deficient diet for 4 wk. SNAC-treated animals （n=6）（1.4 mg/kg/day of SNAC, orally） were compared to 2 control groups： one （n=6） received PBS solution and the other （n=6） received NAC solution （7 mg/kg/d）. Histological variables were semiquantitated with respect to macro and microvacuolar fat changes, its zonal distribution, foci of necrosis, portal and perivenular fibrosis, and inflammatory infiltrate with zonal distribution. LOOHs from samples of liver homogenates were quantified by HPLC. Nitrate levels in plasma of portal vein were assessed by chemiluminescence. Aqueous low-density lipoprotein （LDL） suspensions （200 pg protein/mL） were incubated with CuCl2 （300 μmol/L） in the absence and presence of SNAC （300 μmol/L） for 15 h at 37 ℃ Extent of LDL oxidation was assessed by fluorimetry. Linoleic acid （LA）（18.8 μmol/L） oxidation was induced by soybean lipoxygenase （SLO）（0.056 μmol/L） at 37 ℃ in the presence and absence of N-acetylcysteine （NAC） and SNAC （56 and 560 pmol/L） and monitored at 234 nm. RESULTS： Animals in the control group developed moderate macro and microvesicular fatty changes in periportal area. SNAC-treated animals displayed only discrete histological alterations with absence of fatty changes and did not develop liver steatosis. The absence of NAFLD in the SNAC-treated group was positively correlated with a decrease in the concentration of LOOH in liver homogenate, compared to the control group （0.7±0.2 nmol/mg vs 3.2±0.4 nmol/mg protein, respectively, P〈0.05）, while serum levels of aminotransferases were unaltered. The ability of SNAC in preventing lipid peroxidation was confirmed in in vitro experiments using LA and LDL as model substrates. CONCLUSION： Oral

关键词： Nitric oxide S-nitroso-N-acetylcysteine Oxidative stress Nonalcoholic fatty liver disease

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Oral PTCTS (Particulated Transialidase) Removes Serum Microparticles and Decreases Inflammation in Atherosclerotic Plaques of Rabbits

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Advances in Nanoparticles 2015年第4期4卷 107-115页

作者： Shérrira M. Garavelo Jaqueline J. Pereira Nilsa S. Y. Wadt Marcia M. Reis Renata N. Ikegami Joyce T. Kawakami Abdelali Agouni Suely A. P. Palomino dulcinéia abdalla Maria de Lourdes Higuchi Heart Institute (InCor) University of Sao Paulo Clinics Hospital Sao Paulo Brazil Faculty of Health and Medical Sciences (FHMS) University of Surrey Guildford UK College of Pharmacy Qatar University Doha Qatar Department of Clinical and Toxicological Analysis Faculty of Pharmaceutical Sciences University of Sao Paulo Sao Paulo Brazil

Background: Previous studies showed that atherosclerotic plaque vulnerability was related with microparticles (MPs)-vesicles larger than 100 nm, which released MMP9 collagenase. In our previous study, intramuscular injection of a new drug (PTCTS) normalized oxidized LDL serum levels and reduced rabbit atherosclerosis. Now, we studied administration of oral PTCTS in order to clarify anti-atherosclerotic mechanism of action, analyzing if the treatment removed MPs containing ox-LDL and Mycoplasma pneumoniae antigens and improved the immune response. Methods: We compared two groups of rabbits. Control group (CG, n = 6)—1% cholesterol enriched diet for 12 weeks;Treated group (TG, n = 8)—1% cholesterol enriched diet for 12 weeks with administration of PTCTS (400 μl/day) during the last 6 weeks of diet. The animals had their blood collected, in three different phases of the protocol before being fed with hypercholesterolemic diet, before being treated with water or PTCTS and at the moment of sacrifice. The serum was submitted to immunofluorescence technique to evaluate the quantity of microparticles marked with antibodies against Mycoplasma pneumoniae and ox-LDL. A fragment of aorta was submitted to immunohistochemical detection of antigens from MMP9, ox-LDL, NF-κB and IL-1β. Results: PTCTS showed significant reduction in MMP-9 (P = 0.001) and a tendency of reducing IL-1β (P = 0.09) in the aortic plaques compared with CG. In the serum, PTCTS was able to remove microparticles containing antigen of ox-LDL (P = 0.004) and Mycoplasma pneumoniae (P β and mycoplasma, as well as a better stabilization of the atheromatous plaque by reducing levels of MMP-9, avoiding plaque rupture, without causing mortality or toxicity.

关键词： Atherosclerosis Inflammation PTCTS Mycoplasma NF-κB

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Revolutionizing diabetic retinopathy screening and management:The role of artificial intelligence and machine learning

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World Journal of Clinical Cases 2025年第5期13卷 1-12页

作者： Mona Mohamed Ibrahim abdalla Jaiprakash Mohanraj Department of Human Biology School of MedicineInternational Medical UniversityBukit Jalil 57000Kuala LumpurMalaysia

Diabetic retinopathy(DR)remains a leading cause of vision impairment and blindness among individuals with diabetes,necessitating innovative approaches to screening and *** editorial explores the transformative potential of artificial intelligence(AI)and machine learning(ML)in revolutionizing DR *** and ML technologies have demonstrated remarkable advancements in enhancing the accuracy,efficiency,and accessibility of DR screening,helping to overcome barriers to early *** technologies leverage vast datasets to identify patterns and predict disease progression with unprecedented precision,enabling clinicians to make more informed ***,AI-driven solutions hold promise in personalizing management strategies for DR,incorpo-rating predictive analytics to tailor interventions and optimize treatment *** automating routine tasks,AI can reduce the burden on healthcare providers,allowing for a more focused allocation of resources towards complex patient *** review aims to evaluate the current advancements and applic-ations of AI and ML in DR screening,and to discuss the potential of these techno-logies in developing personalized management strategies,ultimately aiming to improve patient outcomes and reduce the global burden of *** integration of AI and ML in DR care represents a paradigm shift,offering a glimpse into the future of ophthalmic healthcare.

关键词： Diabetic retinopathy Artificial intelligence Machine learning Screening Management Predictive analytics Personalized medicine

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Optimization and Scaling-Up of Peste des Petits Ruminants (PPR) Vaccine Production Using Roller Bottle Platform

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Journal of Biosciences and Medicines 2025年第1期13卷 378-393页

作者： Omer Algezoli Tagelden Nour Muzdalifa Alamin Mohamed abdalla Central Veterinary Research Laboratory Khartoum Sudan College of Veterinary Medicine Sudan University of Science and Technology Khartoum-North Sudan

Peste des Petits ruminants (PPR) is considered as one of the major constraints to the productivity of small ruminants in Sudan. Presently, control measures for PPR are primarily reliant on vaccination using an attenuated PPR strain Nigeria 75/1 that has been produced in monolayers of Vero cells grown in static flasks. This study investigates the potential for scaling up PPR vaccine production using roller bottle technology, a more advanced method. A live, homologous vaccine against PPR in sheep and goats was successfully produced on a large scale in roller culture bottles, with DMEM supplemented with ten percent fetal bovine serum serving as the growth medium. The cells were infected with a multiplicity of infection of 0.01, and the vaccine was harvested when the cytopathic effect reached 80%. The vaccine was then freeze-dried to preserve its stability. A series of tests were conducted to ensure the safety and quality of the vaccine. Using PCR, the identity of vaccine was confirmed. It was found to be safe in both single and 100-times dose inoculations in sheep, with the produced batches showing a high titre of 6.4 ± 0.11 log10 TCID50/ml. All batches met the criteria of sterility, passing tests for bacteria, fungi, and mycoplasma. Furthermore, the vaccine proved effective in small ruminants, with antibodies persisting for over a year post-vaccination. The residual moisture content remained below 2.5%, and the vaccine successfully passed vacuum testing. Stability tests indicated that the vaccine has a shelf-life of at least one year when stored at temperatures of 2˚C - 8˚C and −20˚C. These results demonstrate the potential for applying roller bottle culture technology to PPR vaccine production, significantly streamlining the existing process and enhancing its efficiency. Further research is warranted to address the economic analyses of adopting roller bottle technology with existing PPR control program.

关键词： Large-Scale Production Pest des Petits Ruminants Roller Bottle Technology Vaccination Vero Cell

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Fine-scale analysis reveals a potential influence of forest management on the spatial genetic structure of Eremanthus erythropappus

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Journal of Forestry Research 2021年第4期32卷 1567-1578页

作者： Lucas Fernandes Rocha Natália Ribeiro de Paula dulcinéia De Carvalho Department of Forest Science Federal University of Lavras(UFLA)Av.Doutor Sylvio Menicucci1001 Aquental SolLavrasMinas Gerais State 37200-000Brazil Department of Forest Science College of Agricultural Sciences(FCA/UNESP)São Paulo State UniversityAv.Universitária3780Altos do ParaísoBotucatuSão Paulo State 18610-034Brazil

Forest management may have significant effects on forest connectivity and natural population *** old-growth single trees may also change natural patterns of genetic variation and spatial genetic *** study evaluated the impacts of forest management using a silvicultural system of seed trees on the genetic diversity and spatial genetic structure of Eremanthus erythropappus(DC.)MacLeish.A complete survey of 275 trees on four plots was undertaken out to compare the genetic variation of a managed stand with an unmanaged *** genotyped all adult and juvenile individuals 60 months after the management and compared the genetic diversity and the spatial genetic structure *** diversity was considered high because of an efficient gene flow between *** were no genetic differences between stands and no evidence of *** clustering identified a single population(K=1),indicating no genetic differentiation between managed and unmanaged *** and juvenile individuals of the unmanaged stand were more geographically structured than individuals from the managed *** was a tendency of coancestry among juveniles at the first class of distance of the managed stand,suggesting a drift of genetic structure possibly caused by *** early responses to management on genetic diversity and stand structure is a first step to ensuring the effectiveness of conservation practices of tree *** sustainability of forest management of *** on genetic diversity,and more accurately,on spatial genetic structure needs evaluation over time to promote effective conservation of the population size and genetic variability.

关键词： Genetic diversity Microsatellite markers Gene flow Silvicultural management Brazilian Cerrado

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Therapeutic actions of terpenes in neurodegenerative disorders and their correlations with the regulation and remodeling of the extracellular matrix

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BIOCELL 2025年第1期49卷 109-125页

作者： RENATA DA SILVA CARNEIRO MATEUS HENRIQUE DE ALMEIDA DA COSTA JOSÉZILTON LIMA VERDE SANTOS VALDILÉia TEIXEIRA UCHÔA LUCiaNO DA SILVA LOPES ANDERSON NOGUEIRA MENDES Laboratory of Science in Innovation and Technology-LACITEC Department of Biophysics and PhysiologyFederal University of PiauíTeresina64049Brazil Laboratory of Natural Products and Bioprospecting Natural Sciences CenterState University of PiauíTeresina64018Brazil Laboratory of Experimental Neurochemistry Research-LAPNEX Department of Biophysics and PhysiologyFederal University of PiauíTeresina64049Brazil

Neurodegenerative diseases are a major public health challenge,mainly affecting the elderly population and compromising their cognitive,sensory,and motor ***,available therapies focus on alleviating symptoms and slowing the progression of these conditions,but they do not yet offer a definitive *** this scenario,terpenes emerge as promising natural alternatives due to their neuroprotective *** compounds can reduce the formation of protein aggregates,neutralize free radicals,and inhibit pro-inflammatory enzymes,which are crucial factors in the development of neurodegenerative *** addition,terpenes also play an important role in the regulation and remodeling of the extracellular matrix,a key target for improving neuronal *** such as linalool,pinene,and eugenol,among others,have potential therapeutic effects by modulating inflammatory and oxidative stress processes,the main factors that contribute to the progression of these *** suggest that these compounds act on signaling pathways that regulate the extracellular matrix,improving neuronal integrity and,consequently,cognitive and motor *** work aims to review the potential of terpenes in the treatment of neurodegenerative disorders,with emphasis on their ability to regulate oxidative stress and inflammation,as well as to remodel the extracellular *** interaction between these mechanisms points to the promising use of terpenes as an innovative and natural therapeutic approach to combat these diseases.

关键词： Terpenes Neurodegenerative Disorders Extracellular matrix

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Sero-Prevalence of Peste des Petits Ruminants Virus Antibodies in Sudanese Sheep and Goats before and after Vaccination

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Journal of Biosciences and Medicines 2025年第1期13卷 21-40页

作者： Omer Algezoli Selma Kamal Yazeed Raouf Alamin Mozdalifa Hiba Ali Mohamed Aljameel Salih Sir Elkhatim Sulieman Ahmed Ibtesam Fadul Elsied Tageldin Nour Mohamed abdalla Viral Vaccine Production Department Central Veterinary Research Laboratory Khartoum Sudan College of Veterinary Medicine Sudan University of Science and Technology Khartoum-North Sudan Epidemiology Department Central Veterinary Research Laboratory Khartoum Sudan Foot and Mouth Disease Department Central Veterinary Research Laboratory Khartoum Sudan Virology Department Central Veterinary Research Laboratory Khartoum Sudan Nyala Veterinary Research Laboratory Nyala Sudan Damazine Veterinary Research Laboratory Damazine Sudan Al Obeid Veterinary Research Laboratory Al Obeid Sudan

Peste des petits ruminants virus (PPRV) antibodies were studied in Sudanese sheep and goats (n = 855) before and after vaccination with a locally produced Nigeria 75/1 vaccine using a commercial competitive ELISA (cELISA) kit. Animals were kept healthy under field conditions, in four states: Blue Nile (n = 250), North Kordofan (n = 189), South Darfur (n = 225) and the Northern State (n = 191). Before vaccination, the overall sero-prevalence of PPRV antibodies was 54.6% (53.2% - 56%, 95% CI);high (64.8% - 76.4%, 95% CI) in Blue Nile State, medium (50.5% - 61.9%, 95% CI) in North Kordofan State and South Darfur State and low (28.6% - 35.2% 95%, CI) in Northern State. In high-risk areas (high sero-prevalence), Blue Nile (70.4%) and North Kordofan (57.7%), middle age groups (7 - 12 and 13 - 18 months) were identified as high-risk age. Middle age groups showed lower sero-prevalence than preceding (3 - 6 months) and subsequent (>18 months) age groups while the risk of exposure increased with age. Current and previous findings suggested a transmission pathway of PPRV involving the South Eastern border (Blue Nile) and neighbouring Central Sudan to North Kordofan. One month after vaccination 88.4% (343/388) of sero-negative animals were sero-converted suggesting the efficacy of the locally produced Nigeria 75/1 vaccine. Even if only individuals in the high-risk age group (7 - 18 months) were vaccinated, the overall population immunity (OPI) in high-risk areas (the Blue Nile and North Kordofan) would have surpassed the threshold of 70%, which is indicated for blocking PPRV transmission. However, lower vaccination coverage is expected in wider vaccination programmes. These findings primarily justified the targeting of PPR control in Sudan through the vaccination of high-risk age groups in high-risk areas.

关键词： Peste des Petits Ruminants (PPR) Vaccination Efficacy Seroprevalence Herd Immunity High-Risk Area

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基于中红外光谱和机器学习算法的牛奶中β-乳球蛋白快速检测方法

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华中农业大学学报 2025年

作者：邹慧颖王东薇樊懿楷刘维华杨俊华余文莉 SABEK Ahmed abdalla Ahmed Ibrahim 张淑君华中农业大学动物科学技术学院动物医学院宁夏兽药饲料监察所石家庄天泉良种奶牛有限公司石家庄天泉良种奶牛有限公司博士后科研工作站

为建立一种可以快速、批量、高效检测中国荷斯坦牛牛奶中β-乳球蛋白含量的方法，本试验采集501份来自西北、华北和华中主要产奶地区的健康中国荷斯坦牛牛奶样本，采用高效液相色谱法测定牛奶样本中β-乳球蛋白的含量，并同步测定和收... 详细信息

为建立一种可以快速、批量、高效检测中国荷斯坦牛牛奶中β-乳球蛋白含量的方法，本试验采集501份来自西北、华北和华中主要产奶地区的健康中国荷斯坦牛牛奶样本，采用高效液相色谱法测定牛奶样本中β-乳球蛋白的含量，并同步测定和收集牛奶样本的红外光谱数据（mid-infrared spectroscopy,MIRS）。以MIRS为预测变量，β-乳球蛋白含量为因变量，将12种光谱预处理方法进行连续2次的随机组合，并手动选取特征波段，使用偏最小二乘回归（partial least squares regression,PLSR）作为传统机器学习算法，建立预测牛奶中β-乳球蛋白含量的最优预测模型。结果显示：该模型交叉验证集和测试集的RC2和RP2分别为0.812 9、0.768 8，均方根误差RMSEC和RMSEP分别为0.476 2、0.524 9 g/L,RPD为2.076 6，达到畜禽生产性能的测定要求。试验结果表明，可以利用MIRS建立模型预测中国荷斯坦牛牛奶中的β-乳球蛋白含量。

关键词：中红外光谱牛奶 β-乳球蛋白机器学习算法光谱预处理

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Evaluation of total protein,peroxidase,and nutrients measured by pXRF for the determination of tissue rejuvenation/reinvigoration of Eucalyptus microcorys

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Journal of Forestry Research 2023年第5期34卷 1563-1576页

作者： Júlio Cézar Tannure Faria Caius Ribeiro-Kumara William Macedo Delarmelina Filipe Aiura Namorato Dione Richer Momolli Anderson Cleiton José Enéas Ricardo Konzen dulcinéia de Carvalho Gilvano Ebling Brondani Department of Forestry and Wood Sciences Federal University of Espírito SantoJerônimo MonteiroEspírito SantoBrazil Department of Forest Sciences University of HelsinkiHelsinkiFinland Federal Institute of Education Science and Technology of Espírito SantoIbatibaEspírito SantoBrazil Department of Soil Science Federal University of LavrasLavrasMinas GeraisBrazil Department of Forest Engineering Federal University of Santa MariaSanta MariaRio Grande Do SulBrazil Department of Forestry Sciences Federal University of LavrasLavrasMinas GeraisBrazil Department Interdisciplinary Federal University of Rio Grande Do SulImbéRio Grande Do SulBrazil

Ontogenetic aging of tissues and the gradual decrease of adventitious rooting are known challenges for the clonal propagation of woody species,hampering clonal forestry *** study examined possible signatures of tissue rejuvenation/reinvigoration in different propagated materials of Eucalyptus microcorys by analyzing the total protein profile,peroxidase activity,macro-and micronutrient contents,and adventitious rooting of mini *** analyses were performed on *** shoots which were successfully obtained by seminal and grafting propagation,micropropagation with epicormic shoots,and indirect *** four mature trees used in the propagation,tissues from the one with the best propagation results were investigated for signs of tissue rejuvenation and/or *** individuals from each technique were randomly selected and transferred to a semi-hydroponic"channel"*** four weeks in the seedbed,the total protein,peroxidase activity,nutrient content and rooting of the mini cuttings were ***-PAGE enabled the differentiation of leaf samples obtained by grafting from the other propagation techniques,as revealed by two distinct *** obtained by micropropagation with epicormic shoots showed the highest peroxidase activity,while those obtained by seminal propagation and from the selected mature tree showed the lowest peroxidase activity.A portable X-ray fluorescence spectroscope(pXRF)identified adequate nutrient content in most of the nutrients tested in materials obtained by seminal and grafting propagation,and by indirect *** analysis of adventitious rooting showed that the highest rooting percentage was observed in mini cuttings from seminal propagation(75%)followed by indirect organogenesis(35%).Based on principal component analysis,it was concluded that rooting of mini cuttings from both seminal propagation and indirect organogenesis was associated with phosphorous,sulphur,and potassium

关键词： Adventitious rooting Juvenility Reinvigoration Rejuvenation Ontogenetic age

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Repeated Attribute Optimization for Big Data Encryption

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Computer Systems Science & Engineering 2022年第1期40卷 53-64页

作者： abdalla Alameen Department of Computer Science College of Arts and SciencesPrince Sattam Bin Abdulaziz UniversityAl-KharjSaudi Arabia

Big data denotes the variety,velocity,and massive volume of *** databases are unsuitable to store big data owing to its high *** computing is an optimal solution to process and store big ***,the significant issue lies in handling access control and privacy,wherein the data should be encrypted and unauthorized user access must be restricted through efficient access ***-based encryption(ABE)permits users to encrypt and decrypt ***,for the policy to work in practical scenarios,the attributes must be *** the case of specific policies,it is not possible to avoid attribute repetition even after the application of Boolean optimization approaches to obtain a Boolean *** these policies,there exists a variety of evaluated secret shares for the repeated ***,the calculation of cipher text for these irreducible policies seems to be lengthy and computationally *** address this problem,an improved meta-heuristic-based repeated attributes optimization on cipher-text policy-ABE(CP-ABE)is developed in this ***,the improved meta-heuristic concept is developed in the encryption phase,which returns the optimized single share value of each repeated attribute after considering all the attribute *** optimization process not only minimizes the encryption cost but also the communication ***,the improved sun flower optimization(SFO),called the newly updated SFO(NU-SFO)is used to perform the repeated attribute optimization in ***,the performance evaluation confirms the reliability and robustness of the developed scheme through comparisons with traditional constructions.

关键词： Bigdata repeatedattributeoptimization ciphertextpolicy encryption

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