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951.
Surface functionalization of nanobiomaterials for application in stem cell culture,tissue engineering,and regenerative medicine 下载免费PDF全文
Deepti Rana Keerthana Ramasamy Maria Leena Constanza Jiménez Javier Campos Paula Ibarra Ziyad S. Haidar Murugan Ramalingam 《Biotechnology progress》2016,32(3):554-567
Stem cell‐based approaches offer great application potential in tissue engineering and regenerative medicine owing to their ability of sensing the microenvironment and respond accordingly (dynamic behavior). Recently, the combination of nanobiomaterials with stem cells has paved a great way for further exploration. Nanobiomaterials with engineered surfaces could mimic the native microenvironment to which the seeded stem cells could adhere and migrate. Surface functionalized nanobiomaterial‐based scaffolds could then be used to regulate or control the cellular functions to culture stem cells and regenerate damaged tissues or organs. Therefore, controlling the interactions between nanobiomaterials and stem cells is a critical factor. However, surface functionalization or modification techniques has provided an alternative approach for tailoring the nanobiomaterials surface in accordance to the physiological surrounding of a living cells; thereby, enhancing the structural and functional properties of the engineered tissues and organs. Currently, there are a variety of methods and technologies available to modify the surface of biomaterials according to the specific cell or tissue properties to be regenerated. This review highlights the trends in surface modification techniques for nanobiomaterials and the biological relevance in stem cell‐based tissue engineering and regenerative medicine. © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 32:554–567, 2016 相似文献
952.
Biotransformations of Bile Acids with Bacteria from Cayambe Slaughterhouse (Ecuador): Synthesis of Bendigoles 下载免费PDF全文
Stefania Costa Maria Elena Maldonado Rodriguez Irene Rugiero Morena De Bastiani Alessandro Medici Elena Tamburini Paola Pedrini 《化学与生物多样性》2016,13(8):969-975
The biotransformations of cholic acid ( 1a ), deoxycholic acid ( 1b ), and hyodeoxycholic acid ( 1c ) to bendigoles and other metabolites with bacteria isolated from the rural slaughterhouse of Cayambe (Pichincha Province, Ecuador) were reported. The more active strains were characterized, and belong to the genera Pseudomonas and Rhodococcus. Various biotransformation products were obtained depending on bacteria and substrates. Cholic acid ( 1a ) afforded the 3‐oxo and 3‐oxo‐4‐ene derivatives 2a and 3a (45% and 45%, resp.) with P. mendocina ECS10, 3,12‐dioxo‐4‐ene derivative 4a (60%) with Rh. erythropolis ECS25, and 9,10‐secosteroid 6 (15%) with Rh. erythropolis ECS12. Bendigole F ( 5a ) was obtained in 20% with P. fragi ECS22. Deoxycholic acid ( 1b ) gave 3‐oxo derivative 2b with P. prosekii ECS1 and Rh. erythropolis ECS25 (20% and 61%, resp.), while 3‐oxo‐4‐ene derivative 3b was obtained with P. prosekii ECS1 and P. mendocina ECS10 (22% and 95%, resp.). Moreover, P. fragi ECS9 afforded bendigole A ( 8b ; 80%). Finally, P. mendocina ECS10 biotransformed hyodeoxycholic acid ( 1c ) to 3‐oxo derivative 2c (50%) and Rh. erythropolis ECS12 to 6α‐hydroxy‐3‐oxo‐23,24‐dinor‐5β‐cholan‐22‐oic acid ( 9c , 66%). Bendigole G ( 5c ; 13%) with P. prosekii ECS1 and bendigole H ( 8c ) with P. prosekii ECS1 and Rh. erythropolis ECS12 (20% and 16%, resp.) were obtained. 相似文献
953.
Developmental and Environmental Effects on Sesquiterpene Lactones in Cultivated Arnica montana L. 下载免费PDF全文
Milka Todorova Antoaneta Trendafilova Antonina Vitkova Maria Petrova Ely Zayova Daniela Antonova 《化学与生物多样性》2016,13(8):976-981
The amount of sesquiterpene lactones and the lactone profile of Arnica montana L. in flowering and seed formation stages in vitro and in vivo propagated from seeds of German, Ukrainian, and Austrian origin and grown in two experimental fields were studied. It was found that in vitro propagated 2‐year plants in full flowering stage accumulated higher amount of lactones in comparison to in vivo propagated 3‐year plants and to the seed formation stage, respectively. Helenalins predominated in in vivo propagated 2‐year or in vitro propagated 3‐year plants. 2‐Methylbutyrate (2MeBu) was the principal ester in the samples with prevalence of helenalins, while isobutyrate (iBu) was the major one in the samples with predominance of 11,13‐dihydrohelenalins. The results revealed that the environmental conditions on Vitosha Mt. are more suitable for cultivation of A. montana giving higher content of lactones. 相似文献
954.
Genetic and Functional Analysis of Polymorphisms in the Human Dopamine Receptor and Transporter Genes in Small Cell Lung Cancer 下载免费PDF全文
955.
Andrelisse Arruda Viviane Castelo Branco Reis Vinícius Daniel Ferreira Batista Bruno Sahim Daher Luiza Cesca Piva Janice Lisboa De Marco Lidia Maria Pepe de Moraes Fernando Araripe Gonçalves Torres 《Biotechnology letters》2016,38(3):509-517
Objectives
To develop a new vector for constitutive expression in Pichia pastoris based on the endogenous glycolytic PGK1 promoter.Results
P. pastoris plasmids bearing at least 415 bp of PGK1 promoter sequences can be used to drive plasmid integration by addition at this locus without affecting cell growth. Based on this result, a new P. pastoris integrative vector, pPICK2, was constructed bearing some features that facilitate protein production in this yeast: a ~620 bp PGK1 promoter fragment with three options of restriction sites for plasmid linearization prior to yeast transformation: a codon-optimized α-factor secretion signal, a new polylinker, and the kan marker for vector propagation in bacteria and selection of yeast transformants.Conclusions
A new constitutive vector for P. pastoris represents an alternative platform for recombinant protein production and metabolic engineering purposes.956.
Ana Paula Kallaur Josiane Lopes Sayonara Rangel Oliveira Andrea Name Colado Simão Edna Maria Vissoci Reiche Elaine Regina Delicato de Almeida Helena Kaminami Morimoto Wildea Lice Carvalho Jennings de Pereira Daniele Frizon Alfieri Sueli Donizete Borelli Domacio Ramon Kaimen-Maciel Michael Maes 《Molecular neurobiology》2016,53(8):5191-5202
957.
Sperandeo MP Tosco A Izzo V Tucci F Troncone R Auricchio R Romanos J Trynka G Auricchio S Jabri B Greco L 《PloS one》2011,6(7):e21281
Background and Aim
Potential celiacs have the ‘celiac type’ HLA, positive anti-transglutaminase antibodies but no damage at small intestinal mucosa. Only a minority of them develops mucosal lesion. More than 40 genes were associated to Celiac Disease (CD) but we still do not know how those pathways transform a genetically predisposed individual into an affected person. The aim of the study is to explore the genetic features of Potential CD individuals.Methods
127 ‘potential’ CD patients entered the study because of positive anti-tissue transglutaminase and no mucosal lesions; about 30% of those followed for four years become frankly celiac. They were genotyped for 13 polymorphisms of ‘candidate genes’ and compared to controls and celiacs. Moreover, 60 biopsy specimens were used for expression studies.Results
Potential CD bear a lighter HLA-related risk, compared to celiac (χ2 = 48.42; p value = 1×10−8). They share most of the polymorphisms of the celiacs, but the frequency of c-REL* G allele was suggestive for a difference compared to celiac (χ2 = 5.42; p value = 0.02). One marker of the KIAA1109/IL-2/IL-21 candidate region differentiated potentials from celiac (rs4374642: χ2 = 7.17, p value = 0.01). The expression of IL-21 was completely suppressed in potentials compared to celiacs (p value = 0.02) and to controls (p value = 0.02), in contrast IL-2, KIAA1109 and c-REL expression were over-expressed.Conclusions
Potential CD show genetic features slightly different from celiacs. Genetic and expression markers help to differentiate this condition. Potential CD is a precious biological model of the pathways leading to the small intestinal mucosal damage in genetically predisposed individuals. 相似文献958.
Pérez D Crespo M Solé L Prat M Carcasona C Calama E Otal R Gavaldá A Gómez-Angelats M Miralpeix M Puig C 《Bioorganic & medicinal chemistry letters》2011,21(5):1545-1548
The synthesis of diverse functionalized ureas in a semi-parallel fashion is described, as well as their β1/β2-adrenergic activities and the corresponding structure-activity relationship (SAR). We have focused on lipophilicity and duration of action, and we have discovered a strong correlation in this series of molecules. A quantitative structure-activity relationship (QSAR) analysis will be presented that quantifies this relationship. 相似文献
959.
Cornelis MC Monda KL Yu K Paynter N Azzato EM Bennett SN Berndt SI Boerwinkle E Chanock S Chatterjee N Couper D Curhan G Heiss G Hu FB Hunter DJ Jacobs K Jensen MK Kraft P Landi MT Nettleton JA Purdue MP Rajaraman P Rimm EB Rose LM Rothman N Silverman D Stolzenberg-Solomon R Subar A Yeager M Chasman DI van Dam RM Caporaso NE 《PLoS genetics》2011,7(4):e1002033
We report the first genome-wide association study of habitual caffeine intake. We included 47,341 individuals of European descent based on five population-based studies within the United States. In a meta-analysis adjusted for age, sex, smoking, and eigenvectors of population variation, two loci achieved genome-wide significance: 7p21 (P = 2.4 × 10(-19)), near AHR, and 15q24 (P = 5.2 × 10(-14)), between CYP1A1 and CYP1A2. Both the AHR and CYP1A2 genes are biologically plausible candidates as CYP1A2 metabolizes caffeine and AHR regulates CYP1A2. 相似文献
960.
Donati M Di Francesco A Delucca F Di Paolo M Battilani M Balboni A Baldelli R Cevenini R 《FEMS immunology and medical microbiology》2011,61(1):125-128
It is known that neutralizing species-specific or serovar-specific antibodies are produced in response to chlamydial infection in humans and in some animal species. In a previous study, a strong in vitro neutralizing activity to Chlamydia suis in 80% of sera from C. suis-infected pigs had been observed. In view of the close relationship between C. suis and Chlamydia trachomatis, in the present study, the neutralizing activity against D-K C. trachomatis and C. suis purified elementary bodies (EBs) in sera collected from C. trachomatis-infected patients and C. suis-infected pigs was evaluated. A neutralizing activity of 50-70% was observed in the human sera against the homologous serovar and one to five heterologous C. trachomatis serovars. These sera were also able to neutralize C. suis EBs. The pig sera showed a strong neutralizing activity (70-100%) against C. suis EBs and all eight urogenital C. trachomatis serovars. These results suggested the presence of common immunogenic antigens in C. trachomatis and C. suis. Immunoblot analysis, performed to elucidate the target of this neutralizing activity, showed a clear reactivity in human and pig sera against two proteins of 150 and 40 kDa MW, when tested either with C. trachomatis or with C. suis EBs. 相似文献