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Biocatalytic production of chitosan polymers from shrimp shells,using a recombinant enzyme produced by Pichia pastoris

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American Journal of Molecular Biology 2012年第4期2卷 341-350页

作者： Eduardo Mere del Aguila Laidson Paes Gomes Cristina Tristao Andrade Joab Trajano Silva Vania Margaret Flosi Paschoalin Universidade Federal do rio de Janeiro Instituto de QuímicaRio de JaneiroBrazil Universidade Federal do rio de Janeiro Instituto de Macromoléculas Professora Eloisa ManoRio de JaneiroRJBrazil

Chitosan has a unique chemical structure with high charge density, reactive hydroxyl and amino groups, and extensive hydrogen bonding. Chitin deacetylase (EC 3.***.1.41) catalyzes the hydrolysis of the N-acetamido groups of N-acetyl-D-glucosamine residues in chitin, converting it to chitosan and releasing acetate. The entire ORF of the CDA2 gene encoding one of the two isoforms of chitin deacetylase from Saccharomyces cerevisiae was cloned in Pichia pastoris. The Tg (Cda2-6xHis)p was expressed at high levels as a soluble intracellular protein after induction of the recombinant yeast culture with methanol, and purified using nickel-nitrilotriacetic acid chelate affinity chromatography, resulting in a protein preparation with a purity of >98% and an overall yield of 79%. Chitin deacetylase activity was measured by a colorimetric method based on the O-phthalaldehyde reagent, which detects primary amines remaining in chitinous substrate after acetate release. The recombinant enzyme could deacetylate chitin, chitobiose, chitotriose and chitotetraose, with an optimum temperature of 50°C and pH 8.0, determined using oligochitosaccharides as the substrates. The recombinant protein was also able to deacetylate its solid natural substrate, shrimp chitin, to a limited extent, producing chitosan with a degree of acetylation (DA) of 89% as determined by Fourier transform infrared spectroscopy. The degree of deacetylation was increased by pre-hydrolysis of crystalline shrimp chitin by chitinases, which increased the deacetylation ratio triggered by chitin deacetylase, producing chito-oligosaccharides with a degree of acetylation of 33%. The results described here open the possibility to use the rCda2p, combined with chitinases, for biocatalytic conversion of chitin to chitosan with controlled degrees of deacetylation. We show herein that the crystalline chitin form can be cleanly produced in virtually quantitative yield if a combined and sequential enzyme treatment is performed.

关键词： Chitin Deacetylase Chitosan Chitin Pichia Pastoris Deacetylation Degree

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美国野生马铃薯群体的生态地理变量和RAPD标记变异间的关系

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国外作物育种 2001年第4期20卷 51-51页

作者：邱敦莲 A.H.del rio 等

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白质发育不良、小头畸形、大脑畸形(LMC):一种新型2p16连锁隐性遗传性疾病

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世界核心医学期刊文摘(神经病学分册) 2006年第4期 40-40页

作者： Chandler K.E. del rio A. RakshiK. D.T. Pilz 陈海 Institute of Medical Genetics University Hospital of Wales Heath Park Cardiff CF14 4XW United Kingdom.Dr

We report three related and one unrelated child with an apparently novel neurodevelopmental disorder. The clinical course was very similar in all the four patients: congenital microcephaly with severe failure of post-natal brain growth, neonatal onset of intractable seizures associated with lack of developmental progression and death within the first 3 years of life. The appearance on cerebral neuroimaging was almost identical, with simplified gyration associated with a non-thickened cortex, severe hypoplasia of the corpus callosum, a small flattened brain stem, and specific cystic lesions in the white matter around the temporal and occipital horns. To our knowledge these patients represent a previously unreported, autosomal recessive syndrome. Homozygosity mapping in the consanguineous family has identified a candidate region on the chromosome 2p16.

关键词：白质髓质发育不良 LMC

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The Effectiveness of Diamel in the Treatment of Type 2 Diabetic Patients Receiving Insulin Therapy: A Randomized, Controlled Clinical Trial

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Open Journal of Endocrine and Metabolic Diseases 2012年第4期2卷 117-124页

作者： María Elena de la Uz Herrera Arturo Hernández Yero Reinaldo González Iglesias Urbicio Reinoso Hernández Alfredo Novales Amado María del Carmen Herrera de la Uz Marién García Otero Diabetic Care Centre Hospital Abel Santamaría Cuadrado Pinar del Río Cuba Endocrinology Service Instituto Nacional de Endocrinología Havana Cuba Internal Medicine Service Hospital Abel Santamaría Cuadrado Pinar del Río Cuba Medical University Physiology Department Pinar del Río Cuba Rehabilitation Service Hospital León Cuervo Rubio Pinar del Río Cuba

Aims/Introduction: Effectiveness of Diamel? on the biochemical variables: fasting blood glucose, postprandial glucose, cholesterol, triglycerides, and glycosylated haemoglobin [Hba1c] in type-2 diabetic patients receiving insulin terapy. Diamel is a natural product composed of trace elements: amino acids, vitamins, cranberry extract, and lettuce extract that have been activated by means of a magnetization process. Materials and methods: Randomized, doubleblind, comparator-controlled clinical trial. A central randomization centre used computer generated tables to allocate treatments. 116 patients suffering from type-2 diabetes mellitus treated with insulin at the Diabetes Care Centre in Pinar del rio (Cuba), were recruited and randomly. The subjects were separated into two groups: Group A (n = 59), who were administered Diamel and Group B (n = 57) using placebo. The clinical and biochemical variables were assessed for 24 weeks. Results: Two subjects were excluded from the Diamel treatment group during the clinical trial. From the statistical point of view, a significant drop in the levels of the baseline glucose, postprandial glucose, glycated haemoglobin, and triglycerides was observed in the group taking Diamel (Group A). There was observed an increase in insulin requirements and in waist circumference in the subjects of Group B There was not reported any severe or serious adverse reactions during this clinical trial. Conclusion: Diamel (nutritional supplement) together with the administration of insulin in type-2 diabetic patients is useful to optimize the biochemical variables (baseline and postprandial glucose, Hb A1C, plus triglycerides), as well as to prevent the increase of insulin requirements at medium-term.

关键词： Diamel Dietary Supplement Type-2 Diabetes Clinical Trial Double-Blind

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Identification of Arceuthobium globosum using unmanned aerial vehicle images in a high mountain forest of central Mexico

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Journal of Forestry Research 2020年第5期31卷 1759-1771页

作者： Luis A.Leon-banuelos Angel R.Endara-Agramont William Gomez-Demetrio Carlos G.Martınez-Garcıa E.Gabino Nava-Bernal 50000 TolucaMexicoMexico

The identification of forests infested by parasitic plants is important for the design of appropriate control and prevention *** images and geographic information systems are commonly used to analyze the presence of pest and parasitic plants in the *** there is a need for finer *** the last decade,the use of unmanned aerial vehicles has become increasingly common for capturing aerial images(<10 cm per pixel).The objective of the study was to obtain RGB values(Red,Green and Blue)through the colorimetric ranges for use in identification of Yellow Dwarf Mistletoe(YDM)(Arceuthobium globosum)in aerial images taken in a forest of central Mexico via a programmed *** tonalities of YDM were classified according to its phenological stages,***(young stage),yellow(adult stage),and brown(senescence stage),considering two light intensities,sunny and ***-parametric tests were used in statistical *** Spearman test showed significant negative correlation(p<0.001)between phenological stage and colour,indicating that lower RGB values were associated with greater *** differences between groups were analysed using Kruskal–Wallis(p<0.01)and Mann–Whitney tests(p<0.01).The applied algorithm identified the presence and predominant colours of YDM according to its phenological stage.

关键词： Colorimetric analysis RGB Pinus hartweggi Parasitic plants Remote sensing

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Robotic4all project:Results of a hands-on robotic surgery training program

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Laparoscopic, Endoscopic and Robotic Surgery 2023年第1期6卷 1-8页

作者： Mario Rui Gonçalves Jose Novo de Matos Antonio Oliveira Ricardo Marinho Irene Cadime Palmira Carlos Alves Salvador Morales-Conde Miguel Castelo-Branco Faculty of Health Sciences University of Beira InteriorCovilha 6200-506Portugal Centro Hospitalar Universitario Lisboa Central Hospital de Sao JoseLisboa 1150-199Portugal Centro Hospitalar de Tras-os-Montes e Alto Douro Vila Real 5000-508Portugal Centro Hospitalar de Leiria Hospital de Santo AndreLeiria 2410-197Portugal Centro de Investigaçao em Psicologia Escola de Psicologia-Universidade do MinhoBraga 4710-057Portugal Departamento de Estudos Curriculares e Tecnologia Educativa Instituto de Educaçao-Universidade do MinhoCampus de GualtarBraga 4710-093Portugal Unit of Innovation in Minimally Invasive Surgery University Hospital Virgen del RocioUniversity of SevillaSeville 41013Spain

Objective Although robotic surgery adoption and its indications are growing worldwide,for multiple factors,including costs,there is a lack of training and *** aim was to study the impact of a robotic introduction training program on gesture performance,such as suturing,in robot-naive *** Using the DaVinci robot,a 2-hour program was based on virtual reality and anatomical model *** participants performed 3 repetitions of virtual reality exercises on the virtual simulator,and then performed and were assessed on 2 tests,ie robot and laparoscopic training *** the course,the participants were surveyed for this training *** Twenty-seven residents and surgeons were enrolled in the training *** only 2 hours of training,all of the participants were able to complete the training program,thus learning generic and specific skills in robotic *** virtual reality exercise,the scores of the 3 exercises increased significantly with every repetition(p<0.001)and the size of the increase was *** completion time on the robot platform was 2.6 times faster(169.33±28.28 s vs.447.96±156.55 s,p<0.001)than that in the laparoscopic box,and the difference between both types of tests was large(pη2=0.797).The centralization and passage of the needle were significantly better on the robot platform(5 vs.3,p<0.001,r=0.47;5 vs.4,p<0.001,r=0.59)than in the laparoscopic *** the intracorporeal stitch+knot test,every participant was able to perform the exercise on the robot but only 85.2%(23/27)in the laparoscopic ***-one participants answered the survey,and 13(61.9%)of them considered robotic performance independent of laparoscopic *** Surgeons are interested and seek training in robotic *** implemented the first hands-on robotic surgery training program in Portugal and participants considered it was important and adequate for its *** participants,even without robotic experience,lear

关键词： Simulation Education Laparoscopic suture Laparoscopy Robotic surgery

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阑尾长度是急性阑尾炎的独立风险因素

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国际医学放射学杂志 2014年第1期 96-96页

作者： J.P.Pickhard J.Suhonen E.M.Lawrence A.M.del rio B.D.Pooler 石伟 Department of Radiology University of Wisconsin School of Medicine & Public Health E3/311 Clinical Science Center600 Highland Ave. Madison WI 53792-3252 USA

目的确定急性阑尾炎和无症状对照组之间阑尾长度是否存在差异。方法比较321例手术证实为阑尾炎的病人与连续的321例无症状成人CT上所见阑尾长度。在沿

关键词：阑尾炎阑尾多层CT 解剖学

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Angiotensin-(1-7)and Human Chorionic Gonadotropin(hCG)Modulate the Nuclear Transcription Factors or Nuclear Receptors Genes in the Tumorigenic Undifferentiated Breast Cancer Cell Line SKBR3

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Journal of Cancer Therapy 2013年第7期4卷 70-74页

作者： Isidoro Binda Neto Samuel Marcos Ribeiro de Noronha Silvana Aparecida Alves Correa de Noronha Maria del Carmen Garcia Molina Wolgien Alexandre Jesus barros Clovis Ryiuchi Nakaie Suma Imura Shimuta Gil Facina Ismael Dale Cotrim Guerreiro da Silva Laboratorio de Ginecologia Molecular Universidade Federal de Sao PauloSao PauloBrazil Universidade Federal do Estado do rio de Janeiro Rio de JaneiroBrazil Laboratorio de Cirurgia Translacional Departamento de CirurgiaUNIFESP/EPMSao PauloBrazil Departamento de Biofísica Universidade Federal de Sao PauloSao PauloBrazil

Breast cancer is the most common cancer among women. Angiotensin-(1 - 7) [Ang-(1 - 7)] has been correlated with cancer antiproliferative and apoptotic effects, similar properties of the human Chorionic Gonadotrofin (hCG). The aims of this work are to evaluate the role of Ang-(1 - 7) and of hCG in modulating the expression of Nuclear Receptors and Coregulators related genes in the tumorigenic breast cell line SK-BR3. Three experimental groups were created: control, hCG and hCG + Ang-(1 - 7). Cells were treated for 11 days and then had their RNA extracted. Samples were loaded into PCR Array plates containing 84 genes relate to Nuclear Receptors and Coregulators pathways. Gene expression data were used to construct canonical pathways (MetacoreTM). hCG and hCG + Ang-(1 - 7) treatments markedly modulate the expression of Nuclear Receptors and Coregulators related genes. hCG differentially expressed 17% of the genes, being 29% upregulated and 71% downregulated. Meanwhile, hCG + Ang-(1 - 7) changed the expression of 30% of the genes on the plate, among these genes 56% were upregulated and 44% downregulated. Among these differentially expressed genes, we highlight Esr1, Nr2f2, and Nr2f1, Esr1, Hdac5, and Nr4A1 (>4 fold). Finally MetaCore analysis based on Gene Ontology (GO) generated six networks for hCG and ten networks for the combined treatment. All generated networks are related to regulation of apoptosis or to Programmed Cell Death processes. In summary, our results herein demonstrate that the modulation of sexual hormones and of other nuclear factor genes expression might underlie the tumorigenic protection effect and the induction of cell differentiation caused by the hormones hCG and Ang-(1 - 7), especially in Cancer Stem Cells.

关键词： Breast Stem Cancer Cells SK-BR3 hCG Angiotensin-(1-7)

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肾动脉狭窄的非对比增强MRA:猪模型的DSA验证

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国际医学放射学杂志 2016年第2期 218-218页

作者： T.A.Bley C.J.Franois M.L.Schiebler A.Munoz del rio O.Wieben N.Takei 任冬晴 Department of Diagnostic and Interventional Radiology University of Wurzburg

摘要目的使用数字剪影血管造影(DSA)作为参考标准比较三维反转恢复平衡稳态自由进动(IR-b SSFP)非对比增强MR血管成像(MRA)和三维对比增强磁共振血管成像(CE-MRA)在肾动脉狭窄(RAS)评定中的价值。材料与方法对12只猪进行双侧肾动脉狭窄... 详细信息

摘要目的使用数字剪影血管造影(DSA)作为参考标准比较三维反转恢复平衡稳态自由进动(IR-b SSFP)非对比增强MR血管成像(MRA)和三维对比增强磁共振血管成像(CE-MRA)在肾动脉狭窄(RAS)评定中的价值。材料与方法对12只猪进行双侧肾动脉狭窄手术,在1.5 T MRI上进行IR-b SSFP和CE-MRA并与旋转DSA对比。3位有经验的心血管放射科医师独立评估IR-b SSFP和CE-MRA研究结果。用线性回归模型校准和评估IR-b SSFP和CE-MRA的准确

关键词： MRA CE IR 对比增强肾动脉狭窄动脉疾病 DSA

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Diffuse intestinal ganglioneuromatosis an uncommon manifestation of Cowden syndrome

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World Journal of Gastrointestinal Oncology 2013年第2期5卷 34-37页

作者： Maria Teresa Herranz bachiller Jesus ba.rio Andrés Fernando Pons Noelia Alcaide Suárez Rafael Ruiz-Zorrilla Lorena Sancho del Val Sara Lorenzo Pelayo Carlos De La Serna Higuera Ramon Atienza Sánchez Manuel Perez Miranda Department of Gastroenterology Rio Hortega Hospital

Diffuse intestinal ganglioneuromatosis is a hamartomatous polyposis characterized by a disseminated, intramural or transmural proliferation of neural elements involving the enteric plexuses. It has been associated with MEN Ⅱ, neurofibromatosis type 1 and hamartomatous polyposis associated with phosphatase and tensin homolog mutation. We report the case of a female patient with a history of a breast and endometrial tumor who presented in a colonoscopy performed for rectal bleeding diffuse ganglioneuromatosis, which oriented the search for other characteristic findings of Cowden syndrome given the personal history of the patient. The presence of an esophagogastric polyposis was also noted. Cowden syndrome is characterized by skin lesions, but it is rarely diagnosed by these lesions, because they are usually overlooked. Intestinal polyposis is not a major diagnostic criterion but it is very useful for early diagnosis. The combination of colonic polyposis and glucogenic acanthosis should orient the diagnosis to Cowden syndrome.

关键词： Ganglioneuromatosis Gastrointestinal poliposis Phosphatase and tensin homolog Cowden síndrome Hamartoma

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