Li, M-H; Tiirikka, T; Kantanen, J
2014-01-01
In sheep, coat colour (and pattern) is one of the important traits of great biological, economic and social importance. However, the genetics of sheep coat colour has not yet been fully clarified. We conducted a genome-wide association study of sheep coat colours by genotyping 47 303 single-nucleotide polymorphisms (SNPs) in the Finnsheep population in Finland. We identified 35 SNPs associated with all the coat colours studied, which cover genomic regions encompassing three known pigmentation genes (TYRP1, ASIP and MITF) in sheep. Eighteen of these associations were confirmed in further tests between white versus non-white individuals, but none of the 35 associations were significant in the analysis of only non-white colours. Across the tests, the s66432.1 in ASIP showed significant association (P=4.2 × 10−11 for all the colours; P=2.3 × 10−11 for white versus non-white colours) with the variation in coat colours and strong linkage disequilibrium with other significant variants surrounding the ASIP gene. The signals detected around the ASIP gene were explained by differences in white versus non-white alleles. Further, a genome scan for selection for white coat pigmentation identified a strong and striking selection signal spanning ASIP. Our study identified the main candidate gene for the coat colour variation between white and non-white as ASIP, an autosomal gene that has been directly implicated in the pathway regulating melanogenesis. Together with ASIP, the two other newly identified genes (TYRP1 and MITF) in the Finnsheep, bordering associated SNPs, represent a new resource for enriching sheep coat-colour genetics and breeding. PMID:24022497
Eizirik, Eduardo; David, Victor A.; Buckley-Beason, Valerie; Roelke, Melody E.; Schäffer, Alejandro A.; Hannah, Steven S.; Narfström, Kristina; O'Brien, Stephen J.; Menotti-Raymond, Marilyn
2010-01-01
Mammalian coat patterns (e.g., spots, stripes) are hypothesized to play important roles in camouflage and other relevant processes, yet the genetic and developmental bases for these phenotypes are completely unknown. The domestic cat, with its diversity of coat patterns, is an excellent model organism to investigate these phenomena. We have established three independent pedigrees to map the four recognized pattern variants classically considered to be specified by a single locus, Tabby; in order of dominance, these are the unpatterned agouti form called “Abyssinian” or “ticked” (Ta), followed by Spotted (Ts), Mackerel (TM), and Blotched (tb). We demonstrate that at least three different loci control the coat markings of the domestic cat. One locus, responsible for the Abyssinian form (herein termed the Ticked locus), maps to an ∼3.8-Mb region on cat chromosome B1. A second locus controls the Tabby alleles TM and tb, and maps to an ∼5-Mb genomic region on cat chromosome A1. One or more additional loci act as modifiers and create a spotted coat by altering mackerel stripes. On the basis of our results and associated observations, we hypothesize that mammalian patterned coats are formed by two distinct processes: a spatially oriented developmental mechanism that lays down a species-specific pattern of skin cell differentiation and a pigmentation-oriented mechanism that uses information from the preestablished pattern to regulate the synthesis of melanin profiles. PMID:19858284
Eizirik, Eduardo; David, Victor A; Buckley-Beason, Valerie; Roelke, Melody E; Schäffer, Alejandro A; Hannah, Steven S; Narfström, Kristina; O'Brien, Stephen J; Menotti-Raymond, Marilyn
2010-01-01
Mammalian coat patterns (e.g., spots, stripes) are hypothesized to play important roles in camouflage and other relevant processes, yet the genetic and developmental bases for these phenotypes are completely unknown. The domestic cat, with its diversity of coat patterns, is an excellent model organism to investigate these phenomena. We have established three independent pedigrees to map the four recognized pattern variants classically considered to be specified by a single locus, Tabby; in order of dominance, these are the unpatterned agouti form called "Abyssinian" or "ticked" (T(a)), followed by Spotted (T(s)), Mackerel (T(M)), and Blotched (t(b)). We demonstrate that at least three different loci control the coat markings of the domestic cat. One locus, responsible for the Abyssinian form (herein termed the Ticked locus), maps to an approximately 3.8-Mb region on cat chromosome B1. A second locus controls the Tabby alleles T(M) and t(b), and maps to an approximately 5-Mb genomic region on cat chromosome A1. One or more additional loci act as modifiers and create a spotted coat by altering mackerel stripes. On the basis of our results and associated observations, we hypothesize that mammalian patterned coats are formed by two distinct processes: a spatially oriented developmental mechanism that lays down a species-specific pattern of skin cell differentiation and a pigmentation-oriented mechanism that uses information from the preestablished pattern to regulate the synthesis of melanin profiles.
Bajaj, Deepak; Das, Shouvik; Upadhyaya, Hari D.; Ranjan, Rajeev; Badoni, Saurabh; Kumar, Vinod; Tripathi, Shailesh; Gowda, C. L. Laxmipathi; Sharma, Shivali; Singh, Sube; Tyagi, Akhilesh K.; Parida, Swarup K.
2015-01-01
The study identified 9045 high-quality SNPs employing both genome-wide GBS- and candidate gene-based SNP genotyping assays in 172, including 93 cultivated (desi and kabuli) and 79 wild chickpea accessions. The GWAS in a structured population of 93 sequenced accessions detected 15 major genomic loci exhibiting significant association with seed coat color. Five seed color-associated major genomic loci underlying robust QTLs mapped on a high-density intra-specific genetic linkage map were validated by QTL mapping. The integration of association and QTL mapping with gene haplotype-specific LD mapping and transcript profiling identified novel allelic variants (non-synonymous SNPs) and haplotypes in a MATE secondary transporter gene regulating light/yellow brown and beige seed coat color differentiation in chickpea. The down-regulation and decreased transcript expression of beige seed coat color-associated MATE gene haplotype was correlated with reduced proanthocyanidins accumulation in the mature seed coats of beige than light/yellow brown seed colored desi and kabuli accessions for their coloration/pigmentation. This seed color-regulating MATE gene revealed strong purifying selection pressure primarily in LB/YB seed colored desi and wild Cicer reticulatum accessions compared with the BE seed colored kabuli accessions. The functionally relevant molecular tags identified have potential to decipher the complex transcriptional regulatory gene function of seed coat coloration and for understanding the selective sweep-based seed color trait evolutionary pattern in cultivated and wild accessions during chickpea domestication. The genome-wide integrated approach employed will expedite marker-assisted genetic enhancement for developing cultivars with desirable seed coat color types in chickpea. PMID:26635822
Zhang, Kai; Lu, Kun; Qu, Cunmin; Liang, Ying; Wang, Rui; Chai, Yourong; Li, Jiana
2013-01-01
Yellow-seed (i.e., yellow seed coat) is one of the most important agronomic traits of Brassica plants, which is correlated with seed oil and meal qualities. Previous studies on the Brassicaceae, including Arabidopsis and Brassica species, proposed that the seed-color trait is correlative to flavonoid and lignin biosynthesis, at the molecular level. In Arabidopsis thaliana, the oxidative polymerization of flavonoid and biosynthesis of lignin has been demonstrated to be catalyzed by laccase 15, a functional enzyme encoded by the AtTT10 gene. In this study, eight Brassica TT10 genes (three from B. napus, three from B. rapa and two from B. oleracea) were isolated and their roles in flavonoid oxidation/polymerization and lignin biosynthesis were investigated. Based on our phylogenetic analysis, these genes could be divided into two groups with obvious structural and functional differentiation. Expression studies showed that Brassica TT10 genes are active in developing seeds, but with differential expression patterns in yellow- and black-seeded near-isogenic lines. For functional analyses, three black-seeded B. napus cultivars were chosen for transgenic studies. Transgenic B. napus plants expressing antisense TT10 constructs exhibited retarded pigmentation in the seed coat. Chemical composition analysis revealed increased levels of soluble proanthocyanidins, and decreased extractable lignin in the seed coats of these transgenic plants compared with that of the controls. These findings indicate a role for the Brassica TT10 genes in proanthocyanidin polymerization and lignin biosynthesis, as well as seed coat pigmentation in B. napus. PMID:23613820
Abitbol, Marie; Legrand, Romain; Tiret, Laurent
2015-04-08
Seven donkey breeds are recognized by the French studbook and are characterized by a black, bay or grey coat colour including light cream-to-white points (LP). Occasionally, Normand bay donkeys give birth to dark foals that lack LP and display the no light points (NLP) pattern. This pattern is more frequent and officially recognized in American miniature donkeys. The LP (or pangare) phenotype resembles that of the light bellied agouti pattern in mouse, while the NLP pattern resembles that of the mammalian recessive black phenotype; both phenotypes are associated with the agouti signaling protein gene (ASIP). We used a panel of 127 donkeys to identify a recessive missense c.349 T > C variant in ASIP that was shown to be in complete association with the NLP phenotype. This variant results in a cysteine to arginine substitution at position 117 in the ASIP protein. This cysteine is highly-conserved among vertebrate ASIP proteins and was previously shown by mutagenesis experiments to lie within a functional site. Altogether, our results strongly support that the identified mutation is causative of the NLP phenotype. Thus, we propose to name the c.[349 T > C] allele in donkeys, the a(nlp) allele, which enlarges the panel of coat colour alleles in donkeys and ASIP recessive loss-of-function alleles in animals.
Molecular genetic analysis of the Phaseolus vulgaris P locus
USDA-ARS?s Scientific Manuscript database
Common bean market classes are distinguished by their many seed colors, patterns, and size. At least 23 genes, acting independently or in an epistatic manner, affect the seed coat color and pattern. The P locus which is described as the “ground factor” by Emerson, has multiple alleles and controls a...
Fontanesi, L; Beretti, F; Riggio, V; Gómez González, E; Dall'Olio, S; Davoli, R; Russo, V; Portolano, B
2009-01-01
In goats, classical genetic studies reported a large number of alleles at the Agouti locus with effects on coat color and pattern distribution. From these early studies, the dominant A(Wt) (white/tan) allele was suggested to cause the white color of the Saanen breed. Here, we sequenced the coding region of the goat ASIP gene in 6 goat breeds (Girgentana, Maltese, Derivata di Siria, Murciano-Granadina, Camosciata delle Alpi, and Saanen), with different coat colors and patterns. Five single nucleotide polymorphisms (SNPs) were identified, 3 of which caused missense mutations in conserved positions of the cysteine-rich carboxy-terminal domain of the protein (p.Ala96Gly, p.Cys126Gly, and p.Val128Gly). Allele and genotype frequencies suggested that these mutations are not associated or not completely associated with coat color in the investigated goat breeds. Moreover, genotyping and sequencing results, deviation from Hardy-Weinberg equilibrium, as well as allele copy number evaluation from semiquantitative fluorescent multiplex PCR, indicated the presence of copy number variation (CNV) in all investigated breeds. To confirm the presence of CNV and evaluate its extension, we applied a bovine-goat cross-species array comparative genome hybridization (aCGH) experiment using a custom tiling array based on bovine chromosome 13. aCGH results obtained for 8 goat DNA samples confirmed the presence of CNV affecting a region of less that 100 kb including the ASIP and AHCY genes. In Girgentana and Saanen breeds, this CNV might cause the A(Wt) allele, as already suggested for a similar structural mutation in sheep affecting the ASIP and AHCY genes, providing evidence for a recurrent interspecies CNV. However, other mechanisms may also be involved in determining coat color in these 2 breeds. Copyright 2009 S. Karger AG, Basel.
NASA Astrophysics Data System (ADS)
Grzincic, E. M.; Yang, J. A.; Drnevich, J.; Falagan-Lotsch, P.; Murphy, C. J.
2015-01-01
Gold nanoparticles (Au NPs) are attractive for biomedical applications not only for their remarkable physical properties, but also for the ease of which their surface chemistry can be manipulated. Many applications involve functionalization of the Au NP surface in order to improve biocompatibility, attach targeting ligands or carry drugs. However, changes in cells exposed to Au NPs of different surface chemistries have been observed, and little is known about how Au NPs and their surface coatings may impact cellular gene expression. The gene expression of two model human cell lines, human dermal fibroblasts (HDF) and prostate cancer cells (PC3) was interrogated by microarray analysis of over 14 000 human genes. The cell lines were exposed to four differently functionalized Au NPs: citrate, poly(allylamine hydrochloride) (PAH), and lipid coatings combined with alkanethiols or PAH. Gene functional annotation categories and weighted gene correlation network analysis were used in order to connect gene expression changes to common cellular functions and to elucidate expression patterns between Au NP samples. Coated Au NPs affect genes implicated in proliferation, angiogenesis, and metabolism in HDF cells, and inflammation, angiogenesis, proliferation apoptosis regulation, survival and invasion in PC3 cells. Subtle changes in surface chemistry, such as the initial net charge, lability of the ligand, and underlying layers greatly influence the degree of expression change and the type of cellular pathway affected.Gold nanoparticles (Au NPs) are attractive for biomedical applications not only for their remarkable physical properties, but also for the ease of which their surface chemistry can be manipulated. Many applications involve functionalization of the Au NP surface in order to improve biocompatibility, attach targeting ligands or carry drugs. However, changes in cells exposed to Au NPs of different surface chemistries have been observed, and little is known about how Au NPs and their surface coatings may impact cellular gene expression. The gene expression of two model human cell lines, human dermal fibroblasts (HDF) and prostate cancer cells (PC3) was interrogated by microarray analysis of over 14 000 human genes. The cell lines were exposed to four differently functionalized Au NPs: citrate, poly(allylamine hydrochloride) (PAH), and lipid coatings combined with alkanethiols or PAH. Gene functional annotation categories and weighted gene correlation network analysis were used in order to connect gene expression changes to common cellular functions and to elucidate expression patterns between Au NP samples. Coated Au NPs affect genes implicated in proliferation, angiogenesis, and metabolism in HDF cells, and inflammation, angiogenesis, proliferation apoptosis regulation, survival and invasion in PC3 cells. Subtle changes in surface chemistry, such as the initial net charge, lability of the ligand, and underlying layers greatly influence the degree of expression change and the type of cellular pathway affected. Electronic supplementary information (ESI) available: UV-Vis spectra of Au NPs, the most significantly changed genes of HDF cells after Au NP incubation under GO accession number GO:0007049 ``cell cycle'', detailed information about the primer/probe sets used for RT-PCR validation of results. See DOI: 10.1039/c4nr05166a
Characterization of the dog agouti gene and a nonagouti mutation in german shepherd dogs
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kerns, Julie A.; Newton, J.; Berryere, Tom G.
The interaction between two genes, Agouti and Melanocortin-1 receptor (Mc1r), produces diverse pigment patterns in mammals by regulating the type, amount, and distribution pattern of the two pigment types found in mammalian hair: eumelanin (brown/black) and pheomelanin (yellow/red). In domestic dogs (Canis familiaris), there is a tremendous variation in coat color patterns between and within breeds; however, previous studies suggest that the molecular genetics of pigment-type switching in dogs may differ from that of other mammals. Here we report the identification and characterization of the Agouti gene from domestic dogs, predicted to encode a 131-amino-acid secreted protein 98 percent identicalmore » to the fox homolog, and which maps to chromosome CFA24 in a region of conserved linkage. Comparative analysis of the Doberman Pinscher Agouti cDNA, the fox cDNA, and 180 kb of Doberman Pinscher genomic DNA suggests that, as with laboratory mice, different pigment-type-switching patterns in the canine family are controlled by alternative usage of different promoters and untranslated first exons. A small survey of Labrador Retrievers, Greyhounds, Australian Shepherds, and German Shepherd Dogs did not uncover any polymorphisms, but we identified a single nucleotide variant in black German Shepherd Dogs predicted to cause an Arg-to-Cys substitution at codon 96, which is likely to account for recessive inheritance of a uniform black coat.« less
Klomtong, P; Chaweewan, K; Phasuk, Y; Duangjinda, M
2015-10-19
Mutations in melanocortin 1 receptor (MC1R) gene and v-kit Hardy-Zuckerman 4 feline sarcoma viral oncogene homolog (KIT) gene have been shown to affect coat color patterns in pigs. Additional functional marker genes, such as insulin like growth factor-2 (IGF2) and orphan nuclear receptor, germ cell nuclear factor (NR6A1), have been described for variations in factors such as fat deposition, litter size, and vertebra number in pigs. In this study, we investigated 129 pigs representing 4 breeds: Thai indigenous, classified into black (similar to Raad or Ka done pig) and black and white (similar to the Hailum and Kwai pig) coat color types; wild boar; Duroc; and Chinese Meishan. Mutations of MC1R, KIT, IGF2, and NR6A1 were detected using polymerase chain reaction-restriction fragment length polymorphism. The genotypes variation in MC1R and KIT genes could be used to differentiate four groups of coat color: solid black, black and white, red, and wild type. For IGF2, the GG genotype was present in wild boar only; for NR6A1 the TT genotype was found only in Duroc pigs. We identified novel 14-bp deletions in KIT that were associated with black and white coat color in Thai indigenous pigs. Insights into variations in genes presented in this study will be useful in future developmental breeding programs for the Thai native pig.
The transcriptional landscape of seasonal coat colour moult in the snowshoe hare.
Ferreira, Mafalda S; Alves, Paulo C; Callahan, Colin M; Marques, João P; Mills, L Scott; Good, Jeffrey M; Melo-Ferreira, José
2017-08-01
Seasonal coat colour change is an important adaptation to seasonally changing environments but the evolution of this and other circannual traits remains poorly understood. In this study, we use gene expression to understand seasonal coat colour moulting in wild snowshoe hares (Lepus americanus). We used hair colour to follow the progression of the moult, simultaneously sampling skin from three moulting stages in hares collected during the peak of the spring moult from white winter to brown summer pelage. Using RNA sequencing, we tested whether patterns of expression were consistent with predictions based on the established phases of the hair growth cycle. We found functionally consistent clustering across skin types, with 766 genes differentially expressed between moult stages. "White" pelage showed more differentially expressed genes that were upregulated relative to other skin types, involved in the transition between late telogen (quiescent stage) and the onset of anagen (proliferative stage). Skin samples from transitional "intermediate" and "brown" pelage were transcriptionally similar and resembled the regressive transition to catagen (regressive stage). We also detected differential expression of several key circadian clock and pigmentation genes, providing important means to dissect the bases of alternate seasonal colour morphs. Our results reveal that pelage colour is a useful biomarker for seasonal change but that there is a consistent lag between the main gene expression waves and change in visible coat colour. These experiments establish that developmental sampling from natural populations of nonmodel organisms can provide a crucial resource to dissect the genetic basis and evolution of complex seasonally changing traits. © 2017 John Wiley & Sons Ltd.
Rapuano, Bruce E.; Hackshaw, Kyle M.; Schniepp, Hannes C.; MacDonald, Daniel E.
2013-01-01
Purpose A number of environmental and patient-related factors contribute to implant failure. A significant fraction of these failures can be attributed to limited osseointegration resulting from poor bone healing responses. The overall goal of this study was to determine whether surface treatment of a titanium-aluminum-vanadium alloy (Ti-6Al-4V) implant material with a biomimetic protein coating could promote the differentiation of attached osteoblastic cells. The specific aims of the study were to investigate whether osteoprogenitor cells cultured on a rigorously cleaned implant specimen showed a normal pattern of differentiation and whether preadsorbed fibronectin accelerated or enhanced osteoblast differentiation. Materials and Methods Ti-6Al-4V disks were rigorously cleaned, passivated in nitric acid, and dry heat–sterilized; some of the disks were then coated with 1 nmol/L fibronectin. MC3T3 osteoprogenitor cells were then cultured on the pretreated disks for several weeks. Quantitative real-time polymerase chain reaction was performed to measure changes over time in the mRNA levels of osteoblast genes. Results Fibronectin increased the peak expression of all analyzed osteoblast gene markers. “Early” genes that normally mark the proliferative phase (0 to 10 days) of osteoblastic development showed peak expression within the first 10 days after cell attachment to the titanium alloy. In contrast, “late” genes that normally mark the differentiation (10 to 20 days) and mineralization (20 to 36 days) phases of osteoblastogenesis achieved peak expression only after approximately 3 to 4 weeks of culture. Conclusions Osteoprogenitors cultured on a rigorously cleaned Ti-6Al-4V alloy were found to demonstrate a normal pattern of osteoblast differentiation. Preadsorbed fibronectin was observed to stimulate osteoblast differentiation during the mineralization phase of osteoblastogenesis. PMID:23057020
Aagaard, Jan E.; Yi, Xianhua; MacCoss, Michael J.; Swanson, Willie J.
2006-01-01
Proteins harboring a zona pellucida (ZP) domain are prominent components of vertebrate egg coats. Although less well characterized, the egg coat of the non-vertebrate marine gastropod abalone (Haliotis spp.) is also known to contain a ZP domain protein, raising the possibility of a common molecular basis of metazoan egg coat structures. Egg coat proteins from vertebrate as well as non-vertebrate taxa have been shown to evolve under positive selection. Studied most extensively in the abalone system, coevolution between adaptively diverging egg coat and sperm proteins may contribute to the rapid development of reproductive isolation. Thus, identifying the pattern of evolution among egg coat proteins is important in understanding the role these genes may play in the speciation process. The purpose of the present study is to characterize the constituent proteins of the egg coat [vitelline envelope (VE)] of abalone eggs and to provide preliminary evidence regarding how selection has acted on VE proteins during abalone evolution. A proteomic approach is used to match tandem mass spectra of peptides from purified VE proteins with abalone ovary EST sequences, identifying 9 of 10 ZP domain proteins as components of the VE. Maximum likelihood models of codon evolution suggest positive selection has acted among a subset of amino acids for 6 of these genes. This work provides further evidence of the prominence of ZP proteins as constituents of the egg coat, as well as the prominent role of positive selection in diversification of these reproductive proteins. PMID:17085584
A Frameshift Mutation in KIT is Associated with White Spotting in the Arabian Camel.
Holl, Heather; Isaza, Ramiro; Mohamoud, Yasmin; Ahmed, Ayeda; Almathen, Faisal; Youcef, Cherifi; Gaouar, Semir; Antczak, Douglas F; Brooks, Samantha
2017-03-09
While the typical Arabian camel is characterized by a single colored coat, there are rare populations with white spotting patterns. White spotting coat patterns are found in virtually all domesticated species, but are rare in wild species. Theories suggest that white spotting is linked to the domestication process, and is occasionally associated with health disorders. Though mutations have been found in a diverse array of species, fewer than 30 genes have been associated with spotting patterns, thus providing a key set of candidate genes for the Arabian camel. We obtained 26 spotted camels and 24 solid controls for candidate gene analysis. One spotted and eight solid camels were whole genome sequenced as part of a separate project. The spotted camel was heterozygous for a frameshift deletion in KIT (c.1842delG, named KITW1 for White spotting 1), whereas all other camels were wild-type (KIT+/KIT+). No additional mutations unique to the spotted camel were detected in the EDNRB, EDN3, SOX10, KITLG, PDGFRA, MITF, and PAX3 candidate white spotting genes. Sanger sequencing of the study population identified an additional five kITW1/KIT+ spotted camels. The frameshift results in a premature stop codon five amino acids downstream, thus terminating KIT at the tyrosine kinase domain. An additional 13 spotted camels tested KIT+/KIT+, but due to phenotypic differences when compared to the KITW1/KIT+ camels, they likely represent an independent mutation. Our study suggests that there are at least two causes of white spotting in the Arabian camel, the newly described KITW1 allele and an uncharacterized mutation.
A Frameshift Mutation in KIT is Associated with White Spotting in the Arabian Camel
Holl, Heather; Isaza, Ramiro; Mohamoud, Yasmin; Ahmed, Ayeda; Almathen, Faisal; Youcef, Cherifi; Gaouar, Semir; Antczak, Douglas F.; Brooks, Samantha
2017-01-01
While the typical Arabian camel is characterized by a single colored coat, there are rare populations with white spotting patterns. White spotting coat patterns are found in virtually all domesticated species, but are rare in wild species. Theories suggest that white spotting is linked to the domestication process, and is occasionally associated with health disorders. Though mutations have been found in a diverse array of species, fewer than 30 genes have been associated with spotting patterns, thus providing a key set of candidate genes for the Arabian camel. We obtained 26 spotted camels and 24 solid controls for candidate gene analysis. One spotted and eight solid camels were whole genome sequenced as part of a separate project. The spotted camel was heterozygous for a frameshift deletion in KIT (c.1842delG, named KITW1 for White spotting 1), whereas all other camels were wild-type (KIT+/KIT+). No additional mutations unique to the spotted camel were detected in the EDNRB, EDN3, SOX10, KITLG, PDGFRA, MITF, and PAX3 candidate white spotting genes. Sanger sequencing of the study population identified an additional five KITW1/KIT+ spotted camels. The frameshift results in a premature stop codon five amino acids downstream, thus terminating KIT at the tyrosine kinase domain. An additional 13 spotted camels tested KIT+/KIT+, but due to phenotypic differences when compared to the KITW1/KIT+ camels, they likely represent an independent mutation. Our study suggests that there are at least two causes of white spotting in the Arabian camel, the newly described KITW1 allele and an uncharacterized mutation. PMID:28282952
Genetic variations associated with six-white-point coat pigmentation in Diannan small-ear pigs
Lü, Meng-Die; Han, Xu-Man; Ma, Yun-Fei; Irwin, David M.; Gao, Yun; Deng, Jia-Kun; Adeola, Adeniyi C.; Xie, Hai-Bing; Zhang, Ya-Ping
2016-01-01
A common phenotypic difference among domestic animals is variation in coat color. Six-white-point is a pigmentation pattern observed in varying pig breeds, which seems to have evolved through several different mechanistic pathways. Herein, we re-sequenced whole genomes of 31 Diannan small-ear pigs from China and found that the six-white-point coat color in Diannan small-ear pigs is likely regulated by polygenic loci, rather than by the MC1R locus. Strong associations were observed at three loci (EDNRB, CNTLN, and PINK1), which explain about 20 percent of the total coat color variance in the Diannan small-ear pigs. We found a mutation that is highly differentiated between six-white-point and black Diannan small-ear pigs, which is located in a conserved noncoding sequence upstream of the EDNRB gene and is a putative binding site of the CEBPB protein. This study advances our understanding of coat color evolution in Diannan small-ear pigs and expands our traditional knowledge of coat color being a monogenic trait. PMID:27270507
Linkage and Segregation Analysis of Black and Brindle Coat Color in Domestic Dogs
Kerns, Julie A.; Cargill, Edward J.; Clark, Leigh Anne; Candille, Sophie I.; Berryere, Tom G.; Olivier, Michael; Lust, George; Todhunter, Rory J.; Schmutz, Sheila M.; Murphy, Keith E.; Barsh, Gregory S.
2007-01-01
Mutations of pigment type switching have provided basic insight into melanocortin physiology and evolutionary adaptation. In all vertebrates that have been studied to date, two key genes, Agouti and Melanocortin 1 receptor (Mc1r), encode a ligand-receptor system that controls the switch between synthesis of red–yellow pheomelanin vs. black–brown eumelanin. However, in domestic dogs, historical studies based on pedigree and segregation analysis have suggested that the pigment type-switching system is more complicated and fundamentally different from other mammals. Using a genomewide linkage scan on a Labrador × greyhound cross segregating for black, yellow, and brindle coat colors, we demonstrate that pigment type switching is controlled by an additional gene, the K locus. Our results reveal three alleles with a dominance order of black (KB) > brindle (kbr) > yellow (ky), whose genetic map position on dog chromosome 16 is distinct from the predicted location of other pigmentation genes. Interaction studies reveal that Mc1r is epistatic to variation at Agouti or K and that the epistatic relationship between Agouti and K depends on the alleles being tested. These findings suggest a molecular model for a new component of the melanocortin signaling pathway and reveal how coat-color patterns and pigmentary diversity have been shaped by recent selection. PMID:17483404
NASA Technical Reports Server (NTRS)
Grugel, Richard N. (Inventor)
2004-01-01
A method is provided for the fabrication of a protective coating for a crucible with channels being formed in the coating. A material is adhered to the outer wall of the crucible to form a pattern thereon. The outer wall of the crucible along with the pattern of material adhered thereto is next coated with another material. The material used to form the pattern should extend through the outer material coating to define at least one port therein. Next, the crucible with its pattern of material and outer coating material is heated to a temperature of transformation at which the pattern of material is transformed to a fluidic state while the crucible and outer coating material maintain their solid integrity. Such transformation could also be accomplished by using a solvent that causes the pattern of material to dissolve. Finally, the material in its fluidic state is removed via the at least one port formed in the outer material coating thereby leaving channels defined in the coating adjacent the outer wall of the crucible.
Method of patterning an aerogel
Reed, Scott T [Edgewood, NM
2012-07-24
A method for producing a pattern in an aerogel disposed as a coating on a substrate comprises exposing the aerogel coating to the vapors of a hydrophobic silane compound, masking the aerogel coating with a shadow photomask and irradiating the aerogel coating with ultraviolet (UV) irradiation. The exposure to UV through the shadow mask creates a pattern of hydrophobic and hydrophilic regions in the aerogel coating. Etching away the hydrophilic regions of the aerogel coating, preferably with a 1 molar solution of sodium hydroxide, leaves the unwetted and unetched hydrophobic regions of the aerogel layer on the substrate, replicating the pattern of the photomask. The hydrophobic aerogel pattern can be further exposed to UV irradiation if desired, to create a hydrophilic aerogel pattern.
Tummala, Seshu B.; Junne, Stefan G.; Papoutsakis, Eleftherios T.
2003-01-01
Plasmid pAADB1 for the overexpression of the alcohol-aldehyde dehydrogenase (aad) gene and downregulation of the coenzyme A transferase (CoAT) using antisense RNA (asRNA) against ctfB (the second CoAT gene on the polycistronic aad-ctfA-ctfB message) was used in order to increase the butanol/acetone ratio of Clostridium acetobutylicum ATCC 824 fermentations. Acetone and butanol levels were drastically reduced in 824(pCTFB1AS) (expresses only an asRNA against ctfB) compared to 824(pSOS95del) (plasmid control). Compared to strain 824(pCTFB1AS), 824(pAADB1) fermentations exhibited two profound differences. First, butanol levels were ca. 2.8-fold higher in 824(pAADB1) and restored back to plasmid control levels, thus supporting the hypothesis that asRNA downregulation of ctfB leads to degradation of the whole aad-ctfA-ctfB transcript. Second, ethanol titers in 824(pAADB1) were ca. 23-fold higher and the highest (ca. 200 mM) ever reported in C. acetobutylicum. Western blot analysis confirmed that CoAT was downregulated in 824(pAADB1) at nearly the same levels as in strain 824(pCTFB1AS). Butyrate depletion in 824(pAADB1) fermentations suggested that butyryl-CoA was limiting butanol production in 824(pAADB1). This was confirmed by exogenously adding butyric acid to 824(pAADB1) fermentations to increase the butanol/ethanol ratio. DNA microarray analysis showed that aad overexpression profoundly affects the large-scale transcriptional program of the cells. Several classes of genes were differentially expressed [strain 824(pAADB1) versus strain 824(pCTFB1AS)], including genes of the stress response, sporulation, and chemotaxis. The expression patterns of the CoAT genes (ctfA and ctfB) and aad were consistent with the overexpression of aad and asRNA downregulation of ctfB. PMID:12775702
Tummala, Seshu B; Junne, Stefan G; Papoutsakis, Eleftherios T
2003-06-01
Plasmid pAADB1 for the overexpression of the alcohol-aldehyde dehydrogenase (aad) gene and downregulation of the coenzyme A transferase (CoAT) using antisense RNA (asRNA) against ctfB (the second CoAT gene on the polycistronic aad-ctfA-ctfB message) was used in order to increase the butanol/acetone ratio of Clostridium acetobutylicum ATCC 824 fermentations. Acetone and butanol levels were drastically reduced in 824(pCTFB1AS) (expresses only an asRNA against ctfB) compared to 824(pSOS95del) (plasmid control). Compared to strain 824(pCTFB1AS), 824(pAADB1) fermentations exhibited two profound differences. First, butanol levels were ca. 2.8-fold higher in 824(pAADB1) and restored back to plasmid control levels, thus supporting the hypothesis that asRNA downregulation of ctfB leads to degradation of the whole aad-ctfA-ctfB transcript. Second, ethanol titers in 824(pAADB1) were ca. 23-fold higher and the highest (ca. 200 mM) ever reported in C. acetobutylicum. Western blot analysis confirmed that CoAT was downregulated in 824(pAADB1) at nearly the same levels as in strain 824(pCTFB1AS). Butyrate depletion in 824(pAADB1) fermentations suggested that butyryl-CoA was limiting butanol production in 824(pAADB1). This was confirmed by exogenously adding butyric acid to 824(pAADB1) fermentations to increase the butanol/ethanol ratio. DNA microarray analysis showed that aad overexpression profoundly affects the large-scale transcriptional program of the cells. Several classes of genes were differentially expressed [strain 824(pAADB1) versus strain 824(pCTFB1AS)], including genes of the stress response, sporulation, and chemotaxis. The expression patterns of the CoAT genes (ctfA and ctfB) and aad were consistent with the overexpression of aad and asRNA downregulation of ctfB.
Hradilová, Iveta; Trněný, Oldřich; Válková, Markéta; Cechová, Monika; Janská, Anna; Prokešová, Lenka; Aamir, Khan; Krezdorn, Nicolas; Rotter, Björn; Winter, Peter; Varshney, Rajeev K.; Soukup, Aleš; Bednář, Petr; Hanáček, Pavel; Smýkal, Petr
2017-01-01
The origin of the agriculture was one of the turning points in human history, and a central part of this was the evolution of new plant forms, domesticated crops. Seed dispersal and germination are two key traits which have been selected to facilitate cultivation and harvesting of crops. The objective of this study was to analyze anatomical structure of seed coat and pod, identify metabolic compounds associated with water-impermeable seed coat and differentially expressed genes involved in pea seed dormancy and pod dehiscence. Comparative anatomical, metabolomics, and transcriptomic analyses were carried out on wild dormant, dehiscent Pisum elatius (JI64, VIR320) and cultivated, indehiscent Pisum sativum non-dormant (JI92, Cameor) and recombinant inbred lines (RILs). Considerable differences were found in texture of testa surface, length of macrosclereids, and seed coat thickness. Histochemical and biochemical analyses indicated genotype related variation in composition and heterogeneity of seed coat cell walls within macrosclereids. Liquid chromatography–electrospray ionization/mass spectrometry and Laser desorption/ionization–mass spectrometry of separated seed coats revealed significantly higher contents of proanthocyanidins (dimer and trimer of gallocatechin), quercetin, and myricetin rhamnosides and hydroxylated fatty acids in dormant compared to non-dormant genotypes. Bulk Segregant Analysis coupled to high throughput RNA sequencing resulted in identification of 770 and 148 differentially expressed genes between dormant and non-dormant seeds or dehiscent and indehiscent pods, respectively. The expression of 14 selected dormancy-related genes was studied by qRT-PCR. Of these, expression pattern of four genes: porin (MACE-S082), peroxisomal membrane PEX14-like protein (MACE-S108), 4-coumarate CoA ligase (MACE-S131), and UDP-glucosyl transferase (MACE-S139) was in agreement in all four genotypes with Massive analysis of cDNA Ends (MACE) data. In case of pod dehiscence, the analysis of two candidate genes (SHATTERING and SHATTERPROOF) and three out of 20 MACE identified genes (MACE-P004, MACE-P013, MACE-P015) showed down-expression in dorsal and ventral pod suture of indehiscent genotypes. Moreover, MACE-P015, the homolog of peptidoglycan-binding domain or proline-rich extensin-like protein mapped correctly to predicted Dpo1 locus on PsLGIII. This integrated analysis of the seed coat in wild and cultivated pea provides new insight as well as raises new questions associated with domestication and seed dormancy and pod dehiscence. PMID:28487704
Use of whole genome expression analysis in the toxicity screening of nanoparticles
DOE Office of Scientific and Technical Information (OSTI.GOV)
Fröhlich, Eleonore, E-mail: eleonore.froehlich@medunigraz.at; Meindl, Claudia; Wagner, Karin
2014-10-15
The use of nanoparticles (NPs) offers exciting new options in technical and medical applications provided they do not cause adverse cellular effects. Cellular effects of NPs depend on particle parameters and exposure conditions. In this study, whole genome expression arrays were employed to identify the influence of particle size, cytotoxicity, protein coating, and surface functionalization of polystyrene particles as model particles and for short carbon nanotubes (CNTs) as particles with potential interest in medical treatment. Another aim of the study was to find out whether screening by microarray would identify other or additional targets than commonly used cell-based assays formore » NP action. Whole genome expression analysis and assays for cell viability, interleukin secretion, oxidative stress, and apoptosis were employed. Similar to conventional assays, microarray data identified inflammation, oxidative stress, and apoptosis as affected by NP treatment. Application of lower particle doses and presence of protein decreased the total number of regulated genes but did not markedly influence the top regulated genes. Cellular effects of CNTs were small; only carboxyl-functionalized single-walled CNTs caused appreciable regulation of genes. It can be concluded that regulated functions correlated well with results in cell-based assays. Presence of protein mitigated cytotoxicity but did not cause a different pattern of regulated processes. - Highlights: • Regulated functions were screened using whole genome expression assays. • Polystyrene particles regulated more genes than short carbon nanotubes. • Protein coating of polystyrene particles did not change regulation pattern. • Functions regulated by microarray were confirmed by cell-based assay.« less
Genomic position affects the expression of tobacco mosaic virus movement and coat protein genes.
Culver, J N; Lehto, K; Close, S M; Hilf, M E; Dawson, W O
1993-01-01
Alterations in the genomic position of the tobacco mosaic virus (TMV) genes encoding the 30-kDa cell-to-cell movement protein or the coat protein greatly affected their expression. Higher production of 30-kDa protein was correlated with increased proximity of the gene to the viral 3' terminus. A mutant placing the 30-kDa open reading frame 207 nucleotides nearer the 3' terminus produced at least 4 times the wild-type TMV 30-kDa protein level, while a mutant placing the 30-kDa open reading frame 470 nucleotides closer to the 3' terminus produced at least 8 times the wild-type TMV 30-kDa protein level. Increases in 30-kDa protein production were not correlated with the subgenomic mRNA promoter (SGP) controlling the 30-kDa gene, since mutants with either the native 30-kDa SGP or the coat protein SGP in front of the 30-kDa gene produced similar levels of 30-kDa protein. Lack of coat protein did not affect 30-kDa protein expression, since a mutant with the coat protein start codon removed did not produce increased amounts of 30-kDa protein. Effects of gene positioning on coat protein expression were examined by using a mutant containing two different tandemly positioned tobamovirus (TMV and Odontoglossum ringspot virus) coat protein genes. Only coat protein expressed from the gene positioned nearest the 3' viral terminus was detected. Analysis of 30-kDa and coat protein subgenomic mRNAs revealed no proportional increase in the levels of mRNA relative to the observed levels of 30-kDa and coat proteins. This suggests that a translational mechanism is primarily responsible for the observed effect of genomic position on expression of 30-kDa movement and coat protein genes. Images Fig. 2 Fig. 3 Fig. 4 PMID:8446627
A process for preparing an ultra-thin, adhesiveless, multi-layered, patterned polymer substrate
NASA Technical Reports Server (NTRS)
Bryant, Robert G. (Inventor); Kruse, Nancy H. M. (Inventor); Fox, Robert L. (Inventor); Tran, Sang Q. (Inventor)
1995-01-01
A process for preparing an ultra-thin, adhesiveless, multi-layered, patterned polymer substrate is disclosed. The process may be used to prepare both rigid and flexible cables and circuit boards. A substrate is provided and a polymeric solution comprising a self-bonding, soluble polymer and a solvent is applied to the substrate. Next, the polymer solution is dried to form a polymer coated substrate. The polymer coated substrate is metallized and patterned. At least one additional coating of the polymeric solution is applied to the metallized, patterned, polymer coated substrate and the steps of metallizing and patterning are repeated. Lastly, a cover coat is applied. When preparing a flexible cable and flexible circuit board, the polymer coating is removed from the substrate.
Qi, Hongfei; Chen, Qiang; Ren, Hailong; Wu, Xianglong; Liu, Xianhu; Lu, Tingli
2018-05-18
Surface modification of metallic implants with bioactive and biodegradable coatings could be a promising approach for bone regeneration. The objective of this study was to prepare chitosan/gelatin nanospheres (GNs) composite coating for the delivery of dexamethasone (DEX). GNs with narrow size distribution and negative surface charge were firstly prepared by a two-step desolvation method. Homogeneous and stable gelatin nanospheres/chitosan (GNs/CTS) composite coatings were formed by electrophoretic deposition (EPD). Drug loading, encapsulation efficiency and in vitro release of DEX were estimated using high performance liquid chromatography (HPLC). The anti-inflammatory effect of DEX-loaded coatings on macrophage RAW 264.7 cells was assessed by the secretion of tumour necrosis factor (TNF) and inducible nitric oxide synthase (iNOS). Osteogenic differentiation of MC3T3-E1 osteoblasts on DEX-loaded coatings was investigated by osteogenic gene expression and mineralization. The DEX in GNs/CTS composite coating showed a two-stage release pattern could not only suppress inflammation during the burst release period, but also promote osteogenic differentiation in the sustained release period. This study might offer a feasible method for modifying the surface of metallic implants in bone regeneration. Copyright © 2018 Elsevier B.V. All rights reserved.
The Use of Mouse Models to Study Epigenetics
Blewitt, Marnie; Whitelaw, Emma
2013-01-01
Much of what we know about the role of epigenetics in the determination of phenotype has come from studies of inbred mice. Some unusual expression patterns arising from endogenous and transgenic murine alleles, such as the Agouti coat color alleles, have allowed the study of variegation, variable expressivity, transgenerational epigenetic inheritance, parent-of-origin effects, and position effects. These phenomena have taught us much about gene silencing and the probabilistic nature of epigenetic processes. Based on some of these alleles, large-scale mutagenesis screens have broadened our knowledge of epigenetic control by identifying and characterizing novel genes involved in these processes. PMID:24186070
Prevalence of unilateral and bilateral deafness in border collies and association with phenotype.
Platt, Simon; Freeman, Julia; di Stefani, Alberta; Wieczorek, Lara; Henley, William
2006-01-01
Congenital sensorineural deafness (CSD) occurs in Border Collies, but its prevalence and inheritance are unknown. This study estimated the prevalence of CSD in Border Collies and investigated its association with phenotypic attributes linked to the merle gene, including coat pigmentation and iris color. Deafness in Border Collies is associated with pigmentation patterns linked to the merle gene. A total of 2597 Border Collies from the United Kingdom. A retrospective study of Border Collies tested, during 1994-2002, by using brainstem auditory evoked responses. Associations between deafness and phenotypic attributes were assessed by using generalized logistic regression. The prevalence of CSD in puppies was estimated as 2.8%. The corresponding rates of unilateral and bilateral CSD were 2.3 and 0.5%, respectively. Adjustment for clustering of hearing status by litter reduced the overall prevalence estimate to 1.6%. There was no association between CSD and sex (P = .2). Deaf Border Collies had higher rates of merle coat pigmentation, blue iris pigment, and excess white on the head than normal hearing Border Collies (all P < .001). The odds of deafness were increased by a factor of 14 for Border Collies with deaf dams, relative to the odds for dogs with normal dams (P = .007), after adjustment for phenotypic attributes. Associations between CSD and pigmentation patterns linked to the merle gene were demonstrated for Border Collies. Evidence for an inherited component to CSD in Border Collies supports selective breeding from only tested and normal parents to reduce the prevalence of this disease.
Black, G C; Perveen, R; Bonshek, R; Cahill, M; Clayton-Smith, J; Lloyd, I C; McLeod, D
1999-10-01
Coats' disease is characterized by abnormal retinal vascular development (so-called 'retinal telangiectasis') which results in massive intraretinal and subretinal lipid accumulation (exudative retinal detachment). The classical form of Coats' disease is almost invariably isolated, unilateral and seen in males. A female with a unilateral variant of Coats' disease gave birth to a son affected by Norrie disease. Both carried a missense mutation within the NDP gene on chromosome Xp11.2. Subsequently analysis of the retinas of nine enucleated eyes from males with Coats' disease demonstrated in one a somatic mutation in the NDP gene which was not present within non-retinal tissue. We suggest that Coats' telangiectasis is secondary to somatic mutation in the NDP gene which results in a deficiency of norrin (the protein product of the NDP gene) within the developing retina. This supports recent observations that the protein is critical for normal retinal vasculogenesis.
Li, Fupeng; Wu, Baoduo; Qin, Xiaowei; Yan, Lin; Hao, Chaoyun; Tan, Lehe; Lai, Jianxiong
2014-08-10
In this study, we performed cloning and expression analysis of six putative sucrose transporter genes, designated TcSUT1, TcSUT2, TcSUT3, TcSUT4, TcSUT5 and TcSUT6, from the cacao genotype 'TAS-R8'. The combination of cDNA and genomic DNA sequences revealed that the cacao SUT genes contained exon numbers ranging from 1 to 14. The average molecular mass of all six deduced proteins was approximately 56 kDa (range 52 to 66 kDa). All six proteins were predicted to exhibit typical features of sucrose transporters with 12 trans-membrane spanning domains. Phylogenetic analysis revealed that TcSUT2 and TcSUT4 belonged to Group 2 SUT and Group 4 SUT, respectively, and the other TcSUT proteins were belonging to Group 1 SUT. Real-time PCR was conducted to investigate the expression pattern of each member of the SUT family in cacao. Our experiment showed that TcSUT1 was expressed dominantly in pods and that, TcSUT3 and TcSUT4 were highly expressed in both pods and in bark with phloem. Within pods, TcSUT1 and TcSUT4 were expressed more in the seed coat and seed from the pod enlargement stage to the ripening stage. TcSUT5 expression sharply increased to its highest expression level in the seed coat during the ripening stage. Expression pattern analysis indicated that TcSUT genes may be associated with photoassimilate transport into developing seeds and may, therefore, have an impact on seed production. Copyright © 2014 Elsevier B.V. All rights reserved.
USDA-ARS?s Scientific Manuscript database
Transgenic Gladiolus plants that contain either Cucumber mosaic virus (CMV) subgroup I coat protein, CMV subgroup II coat protein, CMV replicase, a combination of the CMV subgroups I and II coat proteins, or a combination of the CMV subgroup II coat protein and replicase genes were developed. These...
Wang, Li; Hu, Xiaoyan; Jiao, Chen; Li, Zhi; Fei, Zhangjun; Yan, Xiaoxiao; Liu, Chonghuai; Wang, Yuejin; Wang, Xiping
2016-11-09
Seedlessness in grape (Vitis vinifera) is of considerable commercial importance for both the table grape and processing industries. Studies to date of grape seed development have been made certain progress, but many key genes have yet to be identified and characterized. In this study we analyzed the seed transcriptomes of progeny derived from the V. vinifera seeded maternal parent 'Red Globe' and the seedless paternal parent 'Centennial seedless' to identify genes associated with seedlessness. A total of 6,607 differentially expressed genes (DEGs) were identified and examined from multiple perspectives, including expression patterns, Gene Ontology (GO) annotations, pathway enrichment, inferred hormone influence and epigenetic regulation. The expression data of hormone-related genes and hormone level measurement reveals the differences during seed development between seedless and seeded progeny. Based on both our results and previous studies of A. thaliana seed development, we generated network maps of grape seed-related DEGs, with particular reference to hormone balance, seed coat and endosperm development, and seed identity complexes. In summary, the major differences identified during seed development of seedless and seeded progeny were associated with hormone and epigenetic regulation, the development of the seed coat and endosperm, and the formation of seed identity complexes. Overall the data provides insights into the possible molecular mechanism controlling grape seed size, which is of great importance for both basic research and future translation applications in the grape industry.
Process for Making Ceramic Mold
NASA Technical Reports Server (NTRS)
Buck, Gregory M. (Inventor); Vasquez, Peter (Inventor)
2001-01-01
An improved process for slip casting molds that can be more economically automated and that also exhibits greater dimensional stability is disclosed. The process involves subjecting an investment pattern, preferably made from wax, to successive cycles of wet-dipping in a slurry of colloidal, silica-based binder and dry powder-coating, or stuccoing with plaster of Paris or calcium sulfate mixtures to produce a multi-layer shell over the pattern. The invention as claimed entails applying a primary and a secondary coating to the investment pattern. At least two wet-dipping on in a primary slurry and dry-stuccoing cycles provide the primary coating, and an additional two wet-dippings and dry-stuccoing cycles provide the secondary, or back-up, coating. The primary and secondary coatings produce a multi-layered shell pattern. The multi-layered shell pattern is placed in a furnace first to cure and harden, and then to vaporize the investment pattern, leaving a detailed, high precision shell mold.
Dhungel, Bidur; Ohno, Yoshikazu; Matayoshi, Rie; Otaki, Joji M
2013-03-25
Candidate genes for color pattern formation in butterfly wings have been known based on gene expression patterns since the 1990s, but their functions remain elusive due to a lack of a functional assay. Several methods of transferring and expressing a foreign gene in butterfly wings have been reported, but they have suffered from low success rates or low expression levels. Here, we developed a simple, practical method to efficiently deliver and express a foreign gene using baculovirus-mediated gene transfer in butterfly wings in vivo. A recombinant baculovirus containing a gene for green fluorescent protein (GFP) was injected into pupae of the blue pansy butterfly Junonia orithya (Nymphalidae). GFP fluorescence was detected in the pupal wings and other body parts of the injected individuals three to five days post-injection at various degrees of fluorescence. We obtained a high GFP expression rate at relatively high virus titers, but it was associated with pupal death before color pattern formation in wings. To reduce the high mortality rate caused by the baculovirus treatment, we administered an anti-gp64 antibody, which was raised against baculovirus coat protein gp64, to infected pupae after the baculovirus injection. This treatment greatly reduced the mortality rate of the infected pupae. GFP fluorescence was observed in pupal and adult wings and other body parts of the antibody-treated individuals at various degrees of fluorescence. Importantly, we obtained completely developed wings with a normal color pattern, in which fluorescent signals originated directly from scales or the basal membrane after the removal of scales. GFP fluorescence in wing tissues spatially coincided with anti-GFP antibody staining, confirming that the fluorescent signals originated from the expressed GFP molecules. Our baculovirus-mediated gene transfer system with an anti-gp64 antibody is reasonably efficient, and it can be an invaluable tool to transfer, express, and functionally examine foreign genes in butterfly wings and also in other non-model insect systems.
Frequencies of genes for coat colour and horns in Nordic cattle breeds
Kantanen, Juha; Olsaker, Ingrid; Brusgaard, Klaus; Eythorsdottir, Emma; Holm, Lars-Erik; Lien, Sigbjørn; Danell, Birgitta; Adalsteinsson, Stefan
2000-01-01
Gene frequencies of coat colour and horn types were assessed in 22 Nordic cattle breeds in a project aimed at establishing genetic profiles of the breeds under study. The coat colour loci yielding information on genetic variation were: extension, agouti, spotting, brindle, dun dilution and colour sided. The polled locus was assessed for two alleles. A profound variation between breeds was observed in the frequencies of both colour and horn alleles, with the older breeds generally showing greater variation in observed colour, horn types and segregating alleles than the modern breeds. The correspondence between the present genetic distance matrix and previous molecular marker distance matrices was low (r = 0.08 – 0.12). The branching pattern of a neighbour-joining tree disagreed to some extent with the molecular data structure. The current data indicates that 70% of the total genetic variation could be explained by differences between the breeds, suggesting a much greater breed differentiation than typically found at protein and microsatellite loci. The marked differentiation of the cattle breeds and observed disagreements with the results from the previous molecular data in the topology of the phylogenetic trees are most likely a result of selection on phenotypic characters analysed in this study. PMID:14736370
Patterned structures of graphene and graphitic carbon and methods for their manufacture
Polsky, Ronen; Xiao, Xiaoyin; Burckel, David Bruce; Wheeler, David R.; Brozik, Susan M.; Beechem, Thomas Edwin
2017-01-03
A patterned graphene or graphitic body is produced by providing a three-dimensionally patterned carbonaceous body; coating the body with a catalytic metal whereby is formed a coating having an inner surface proximal the body and an outer surface distal the body; and annealing the coated body under time and temperature conditions effective to form a graphene or graphitic layer on the outer surface of the catalytic metal coating.
Patterned structures of graphene and graphitic carbon and methods for their manufacture
DOE Office of Scientific and Technical Information (OSTI.GOV)
Polsky, Ronen; Xiao, Xiaoyin; Burckel, David Bruce
A patterned graphene or graphitic body is produced by providing a three-dimensionally patterned carbonaceous body; coating the body with a catalytic metal whereby is formed a coating having an inner surface proximal the body and an outer surface distal the body; and annealing the coated body under time and temperature conditions effective to form a graphene or graphitic layer on the outer surface of the catalytic metal coating.
Tian, Xue; Meng, Xiaolin; Wang, Liangyan; Song, Yunfei; Zhang, Danli; Ji, Yuankai; Li, Xuejun; Dong, Changsheng
2015-01-25
Slc7a11 encoding solute carrier family 7 member 11 (amionic amino acid transporter light chain, xCT), has been identified to be a critical genetic regulator of pheomelanin synthesis in hair and melanocytes. To better understand the molecular characterization of Slc7a11 and the expression patterns in skin of white versus brown alpaca (lama paco), we cloned the full length coding sequence (CDS) of alpaca Slc7a11 gene and analyzed the expression patterns using Real Time PCR, Western blotting and immunohistochemistry. The full length CDS of 1512bp encodes a 503 amino acid polypeptide. Sequence analysis showed that alpaca xCT contains 12 transmembrane regions consistent with the highly conserved amino acid permease (AA_permease_2) domain similar to other vertebrates. Sequence alignment and phylogenetic analysis revealed that alpaca xCT had the highest identity and shared the same branch with Camelus ferus. Real Time PCR and Western blotting suggested that xCT was expressed at significantly high levels in brown alpaca skin, and transcripts and protein possessed the same expression pattern in white and brown alpaca skins. Additionally, immunohistochemical analysis further demonstrated that xCT staining was robustly increased in the matrix and root sheath of brown alpaca skin compared with that of white. These results suggest that Slc7a11 functions in alpaca coat color regulation and offer essential information for further exploration on the role of Slc7a11 in melanogenesis. Copyright © 2014 Elsevier B.V. All rights reserved.
Polysaccharide-Coated Magnetic Nanoparticles for Imaging and Gene Therapy
Uthaman, Saji; Cherukula, Kondareddy; Cho, Chong-Su; Park, In-Kyu
2015-01-01
Today, nanotechnology plays a vital role in biomedical applications, especially for the diagnosis and treatment of various diseases. Among the many different types of fabricated nanoparticles, magnetic metal oxide nanoparticles stand out as unique and useful tools for biomedical applications, because of their imaging characteristics and therapeutic properties such as drug and gene carriers. Polymer-coated magnetic particles are currently of particular interest to investigators in the fields of nanobiomedicine and fundamental biomaterials. Theranostic magnetic nanoparticles that are encapsulated or coated with polymers not only exhibit imaging properties in response to stimuli, but also can efficiently deliver various drugs and therapeutic genes. Even though a large number of polymer-coated magnetic nanoparticles have been fabricated over the last decade, most of these have only been used for imaging purposes. The focus of this review is on polysaccharide-coated magnetic nanoparticles used for imaging and gene delivery. PMID:26078971
Miao, Yuanxin; Soudy, Fathia; Xu, Zhong; Liao, Mingxing; Zhao, Shuhong; Li, Xinyun
2017-01-01
Feed efficiency (FE) is a very important trait in livestock industry. Identification of the candidate genes could be of benefit for the improvement of FE trait. Mouse is used as the model for many studies in mammals. In this study, the candidate genes related to FE and coat color were identified using C57BL/6J (C57) × Kunming (KM) F2 mouse population. GWAS results showed that 61 and 2 SNPs were genome-wise suggestive significantly associated with feed conversion ratio (FCR) and feed intake (FI) traits, respectively. Moreover, the Erbin, Msrb2, Ptf1a, and Fgf10 were considered as the candidate genes of FE. The Lpl was considered as the candidate gene of FI. Further, the coat color trait was studied. KM mice are white and C57 ones are black. The GWAS results showed that the most significant SNP was located at chromosome 7, and the closely linked gene was Tyr. Therefore, our study offered useful target genes related to FE in mice; these genes may play similar roles in FE of livestock. Also, we identified the major gene of coat color in mice, which would be useful for better understanding of natural mutation of the coat color in mice.
Fougeroux, André; Petit, Fabien; Anselmo, Anna; Gorni, Chiara; Cucurachi, Marco; Cersini, Antonella; Granato, Anna; Cardeti, Giusy; Formato, Giovanni; Mutinelli, Franco; Giuffra, Elisabetta; Williams, John L.; Botti, Sara
2017-01-01
Honeybees (Apis mellifera) are constantly subjected to many biotic stressors including parasites. This study examined honeybees infected with Nosema ceranae (N. ceranae). N. ceranae infection increases the bees energy requirements and may contribute to their decreased survival. RNA-seq was used to investigate gene expression at days 5, 10 and 15 Post Infection (P.I) with N. ceranae. The expression levels of genes, isoforms, alternative transcription start sites (TSS) and differential promoter usage revealed a complex pattern of transcriptional and post-transcriptional gene regulation suggesting that bees use a range of tactics to cope with the stress of N. ceranae infection. N. ceranae infection may cause reduced immune function in the bees by: (i)disturbing the host amino acids metabolism (ii) down-regulating expression of antimicrobial peptides (iii) down-regulation of cuticle coatings and (iv) down-regulation of odorant binding proteins. PMID:28350872
Method of making nanopatterns and nanostructures and nanopatterned functional oxide materials
Dravid, Vinayak P; Donthu, Suresh K; Pan, Zixiao
2014-02-11
Method for nanopatterning of inorganic materials, such as ceramic (e.g. metal oxide) materials, and organic materials, such as polymer materials, on a variety of substrates to form nanopatterns and/or nanostructures with control of dimensions and location, all without the need for etching the materials and without the need for re-alignment between multiple patterning steps in forming nanostructures, such as heterostructures comprising multiple materials. The method involves patterning a resist-coated substrate using electron beam lithography, removing a portion of the resist to provide a patterned resist-coated substrate, and spin coating the patterned resist-coated substrate with a liquid precursor, such as a sol precursor, of the inorganic or organic material. The remaining resist is removed and the spin coated substrate is heated at an elevated temperature to crystallize the deposited precursor material.
The MYB107 Transcription Factor Positively Regulates Suberin Biosynthesis
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gou, Mingyue; Hou, Guichuan; Yang, Huijun
Suberin, a lipophilic polymer deposited in the outer integument of the Arabidopsis ( Arabidopsis thaliana) seed coat, represents an essential sealing component controlling water and solute movement and protecting seed from pathogenic infection. Although many genes responsible for suberin synthesis are identified, the regulatory components controlling its biosynthesis have not been definitively determined. Here, we show that the Arabidopsis MYB107 transcription factor acts as a positive regulator controlling suberin biosynthetic gene expression in the seed coat. MYB107 coexpresses with suberin biosynthetic genes in a temporal manner during seed development. Disrupting MYB107 particularly suppresses the expression of genes involved in suberinmore » but not cutin biosynthesis, lowers seed coat suberin accumulation, alters suberin lamellar structure, and consequently renders higher seed coat permeability and susceptibility to abiotic stresses. Furthermore, MYB107 directly binds to the promoters of suberin biosynthetic genes, verifying its primary role in regulating their expression. Identifying MYB107 as a positive regulator for seed coat suberin synthesis offers a basis for discovering the potential transcriptional network behind one of the most abundant lipid-based polymers in nature.« less
The MYB107 Transcription Factor Positively Regulates Suberin Biosynthesis
Gou, Mingyue; Hou, Guichuan; Yang, Huijun; ...
2016-12-13
Suberin, a lipophilic polymer deposited in the outer integument of the Arabidopsis ( Arabidopsis thaliana) seed coat, represents an essential sealing component controlling water and solute movement and protecting seed from pathogenic infection. Although many genes responsible for suberin synthesis are identified, the regulatory components controlling its biosynthesis have not been definitively determined. Here, we show that the Arabidopsis MYB107 transcription factor acts as a positive regulator controlling suberin biosynthetic gene expression in the seed coat. MYB107 coexpresses with suberin biosynthetic genes in a temporal manner during seed development. Disrupting MYB107 particularly suppresses the expression of genes involved in suberinmore » but not cutin biosynthesis, lowers seed coat suberin accumulation, alters suberin lamellar structure, and consequently renders higher seed coat permeability and susceptibility to abiotic stresses. Furthermore, MYB107 directly binds to the promoters of suberin biosynthetic genes, verifying its primary role in regulating their expression. Identifying MYB107 as a positive regulator for seed coat suberin synthesis offers a basis for discovering the potential transcriptional network behind one of the most abundant lipid-based polymers in nature.« less
The MYB107 Transcription Factor Positively Regulates Suberin Biosynthesis1[OPEN
Yang, Huijun; Cai, Yuanheng; Kai, Guoyin
2017-01-01
Suberin, a lipophilic polymer deposited in the outer integument of the Arabidopsis (Arabidopsis thaliana) seed coat, represents an essential sealing component controlling water and solute movement and protecting seed from pathogenic infection. Although many genes responsible for suberin synthesis are identified, the regulatory components controlling its biosynthesis have not been definitively determined. Here, we show that the Arabidopsis MYB107 transcription factor acts as a positive regulator controlling suberin biosynthetic gene expression in the seed coat. MYB107 coexpresses with suberin biosynthetic genes in a temporal manner during seed development. Disrupting MYB107 particularly suppresses the expression of genes involved in suberin but not cutin biosynthesis, lowers seed coat suberin accumulation, alters suberin lamellar structure, and consequently renders higher seed coat permeability and susceptibility to abiotic stresses. Furthermore, MYB107 directly binds to the promoters of suberin biosynthetic genes, verifying its primary role in regulating their expression. Identifying MYB107 as a positive regulator for seed coat suberin synthesis offers a basis for discovering the potential transcriptional network behind one of the most abundant lipid-based polymers in nature. PMID:27965303
Pechersky, M.J.
1999-07-06
An improved method for measuring residual stress in a material is disclosed comprising the steps of applying a spot of temperature indicating coating to the surface to be studied, establishing a speckle pattern surrounds the spot of coating with a first laser then heating the spot of coating with a far infrared laser until the surface plastically deforms. Comparing the speckle patterns before and after deformation by subtracting one pattern from the other will produce a fringe pattern that serves as a visual and quantitative indication of the degree to which the plasticized surface responded to the stress during heating and enables calculation of the stress. 3 figs.
Pechersky, Martin J.
1999-01-01
An improved method for measuring residual stress in a material comprising the steps of applying a spot of temperature indicating coating to the surface to be studied, establishing a speckle pattern surrounds the spot of coating with a first laser then heating the spot of coating with a far infrared laser until the surface plastically deforms. Comparing the speckle patterns before and after deformation by subtracting one pattern from the other will produce a fringe pattern that serves as a visual and quantitative indication of the degree to which the plasticized surface responded to the stress during heating and enables calculation of the stress.
2013-01-01
Background Candidate genes for color pattern formation in butterfly wings have been known based on gene expression patterns since the 1990s, but their functions remain elusive due to a lack of a functional assay. Several methods of transferring and expressing a foreign gene in butterfly wings have been reported, but they have suffered from low success rates or low expression levels. Here, we developed a simple, practical method to efficiently deliver and express a foreign gene using baculovirus-mediated gene transfer in butterfly wings in vivo. Results A recombinant baculovirus containing a gene for green fluorescent protein (GFP) was injected into pupae of the blue pansy butterfly Junonia orithya (Nymphalidae). GFP fluorescence was detected in the pupal wings and other body parts of the injected individuals three to five days post-injection at various degrees of fluorescence. We obtained a high GFP expression rate at relatively high virus titers, but it was associated with pupal death before color pattern formation in wings. To reduce the high mortality rate caused by the baculovirus treatment, we administered an anti-gp64 antibody, which was raised against baculovirus coat protein gp64, to infected pupae after the baculovirus injection. This treatment greatly reduced the mortality rate of the infected pupae. GFP fluorescence was observed in pupal and adult wings and other body parts of the antibody-treated individuals at various degrees of fluorescence. Importantly, we obtained completely developed wings with a normal color pattern, in which fluorescent signals originated directly from scales or the basal membrane after the removal of scales. GFP fluorescence in wing tissues spatially coincided with anti-GFP antibody staining, confirming that the fluorescent signals originated from the expressed GFP molecules. Conclusions Our baculovirus-mediated gene transfer system with an anti-gp64 antibody is reasonably efficient, and it can be an invaluable tool to transfer, express, and functionally examine foreign genes in butterfly wings and also in other non-model insect systems. PMID:23522444
Nishi, Mineo; Makishima, Hideo
1996-01-01
A composition for forming anti-reflection film on resist surface which comprises an aqueous solution of a water soluble fluorine compound, and a pattern formation method which comprises the steps of coating a photoresist composition on a substrate; coating the above-mentioned composition for forming anti-reflection film; exposing the coated film to form a specific pattern; and developing the photoresist, are provided. Since the composition for forming anti-reflection film can be coated on the photoresist in the form of an aqueous solution, not only the anti-reflection film can be formed easily, but also, the film can be removed easily by rinsing with water or alkali development. Therefore, by the pattern formation method according to the present invention, it is possible to form a pattern easily with a high dimensional accuracy.
Skin transcriptome profiles associated with coat color in sheep
2013-01-01
Background Previous molecular genetic studies of physiology and pigmentation of sheep skin have focused primarily on a limited number of genes and proteins. To identify additional genes that may play important roles in coat color regulation, Illumina sequencing technology was used to catalog global gene expression profiles in skin of sheep with white versus black coat color. Results There were 90,006 and 74,533 unigenes assembled from the reads obtained from white and black sheep skin, respectively. Genes encoding for the ribosomal proteins and keratin associated proteins were most highly expressed. A total of 2,235 known genes were differentially expressed in black versus white sheep skin, with 479 genes up-regulated and 1,756 genes down-regulated. A total of 845 novel genes were differentially expressed in black versus white sheep skin, consisting of 107 genes which were up-regulated (including 2 highly expressed genes exclusively expressed in black sheep skin) and 738 genes that were down-regulated. There was also a total of 49 known coat color genes expressed in sheep skin, from which 13 genes showed higher expression in black sheep skin. Many of these up-regulated genes, such as DCT, MATP, TYR and TYRP1, are members of the components of melanosomes and their precursor ontology category. Conclusion The white and black sheep skin transcriptome profiles obtained provide a valuable resource for future research to understand the network of gene expression controlling skin physiology and melanogenesis in sheep. PMID:23758853
Functional patterned coatings by thin polymer film dewetting.
Telford, Andrew M; Thickett, Stuart C; Neto, Chiara
2017-12-01
An approach for the fabrication of functional polymer surface coatings is introduced, where micro-scale structure and surface functionality are obtained by means of self-assembly mechanisms. We illustrate two main applications of micro-patterned polymer surfaces obtained through dewetting of bilayers of thin polymer films. By tuning the physical and chemical properties of the polymer bilayers, micro-patterned surface coatings could be produced that have applications both for the selective attachment and patterning of proteins and cells, with potential applications as biomaterials, and for the collection of water from the atmosphere. In all cases, the aim is to achieve functional coatings using approaches that are simple to realize, use low cost materials and are potentially scalable. Copyright © 2017 Elsevier Inc. All rights reserved.
Obermeier, Christian; Hosseini, Bashir; Friedt, Wolfgang; Snowdon, Rod
2009-01-01
Background Serial analysis of gene expression (LongSAGE) was applied for gene expression profiling in seeds of oilseed rape (Brassica napus ssp. napus). The usefulness of this technique for detailed expression profiling in a non-model organism was demonstrated for the highly complex, neither fully sequenced nor annotated genome of B. napus by applying a tag-to-gene matching strategy based on Brassica ESTs and the annotated proteome of the closely related model crucifer A. thaliana. Results Transcripts from 3,094 genes were detected at two time-points of seed development, 23 days and 35 days after pollination (DAP). Differential expression showed a shift from gene expression involved in diverse developmental processes including cell proliferation and seed coat formation at 23 DAP to more focussed metabolic processes including storage protein accumulation and lipid deposition at 35 DAP. The most abundant transcripts at 23 DAP were coding for diverse protease inhibitor proteins and proteases, including cysteine proteases involved in seed coat formation and a number of lipid transfer proteins involved in embryo pattern formation. At 35 DAP, transcripts encoding napin, cruciferin and oleosin storage proteins were most abundant. Over both time-points, 18.6% of the detected genes were matched by Brassica ESTs identified by LongSAGE tags in antisense orientation. This suggests a strong involvement of antisense transcript expression in regulatory processes during B. napus seed development. Conclusion This study underlines the potential of transcript tagging approaches for gene expression profiling in Brassica crop species via EST matching to annotated A. thaliana genes. Limits of tag detection for low-abundance transcripts can today be overcome by ultra-high throughput sequencing approaches, so that tag-based gene expression profiling may soon become the method of choice for global expression profiling in non-model species. PMID:19575793
The effect of process parameters on Twin Wire Arc spray pattern shape
Hall, Aaron Christopher; McCloskey, James Francis; Horner, Allison Lynne
2015-04-20
A design of experiments approach was used to describe process parameter—spray pattern relationships in the Twin Wire Arc process using zinc feed stock in a TAFA 8835 (Praxair, Concord, NH, USA) spray torch. Specifically, the effects of arc current, primary atomizing gas pressure, and secondary atomizing gas pressure on spray pattern size, spray pattern flatness, spray pattern eccentricity, and coating deposition rate were investigated. Process relationships were investigated with the intent of maximizing or minimizing each coating property. It was determined that spray pattern area was most affected by primary gas pressure and secondary gas pressure. Pattern eccentricity was mostmore » affected by secondary gas pressure. Pattern flatness was most affected by primary gas pressure. Lastly, coating deposition rate was most affected by arc current.« less
The effect of process parameters on Twin Wire Arc spray pattern shape
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hall, Aaron Christopher; McCloskey, James Francis; Horner, Allison Lynne
A design of experiments approach was used to describe process parameter—spray pattern relationships in the Twin Wire Arc process using zinc feed stock in a TAFA 8835 (Praxair, Concord, NH, USA) spray torch. Specifically, the effects of arc current, primary atomizing gas pressure, and secondary atomizing gas pressure on spray pattern size, spray pattern flatness, spray pattern eccentricity, and coating deposition rate were investigated. Process relationships were investigated with the intent of maximizing or minimizing each coating property. It was determined that spray pattern area was most affected by primary gas pressure and secondary gas pressure. Pattern eccentricity was mostmore » affected by secondary gas pressure. Pattern flatness was most affected by primary gas pressure. Lastly, coating deposition rate was most affected by arc current.« less
Vigne, Emmanuelle; Komar, Véronique; Fuchs, Marc
2004-04-01
One of the major environmental safety issues over transgenic crops containing virus-derived genes relates to the outcome of recombination events between viral transgene transcripts and RNAs from indigenous virus populations. We addressed this issue by assessing the emergence of viable Grapevine fanleaf virus (GFLV) recombinants in transgenic grapevines expressing the GFLV coat protein (CP) gene. Test plants consisted of nontransgenic scions grafted onto transgenic and nontransgenic rootstocks that were exposed over 3 years to nematode-mediated GFLV infection in two distinct vineyard sites. The CP gene of challenging GFLV isolates was amplified from scions by IC-RT-PCR, and characterized by RFLP and nucleotide sequencing using strain F13 as reference since it provided the CP transgene. Analysis of EcoRI and StyI RFLP banding patterns from 347 challenging GFLV isolates and sequence data from 85 variants revealed no characteristics similar to strain F13 and no difference in the molecular variability among isolates from 190 transgenic and 157 nontransgenic plants, or from plants within (253 individuals) or outside (94 individuals) of the two sites. Interestingly, five GFLV recombinants were identified in three nontransgenic plants located outside of the two field settings. This survey indicates that transgenic grapevines did not assist the emergence of viable GFLV recombinants to detectable levels nor did they affect the molecular diversity of indigenous GFLV populations during the trial period. This is the first report on safety assessment of recombination with a transgenic crop expressing a CP gene under field conditions of heavy disease pressure but low, if any, selection pressure against recombinant viruses.
Genetic subdivision and candidate genes under selection in North American grey wolves.
Schweizer, Rena M; vonHoldt, Bridgett M; Harrigan, Ryan; Knowles, James C; Musiani, Marco; Coltman, David; Novembre, John; Wayne, Robert K
2016-01-01
Previous genetic studies of the highly mobile grey wolf (Canis lupus) found population structure that coincides with habitat and phenotype differences. We hypothesized that these ecologically distinct populations (ecotypes) should exhibit signatures of selection in genes related to morphology, coat colour and metabolism. To test these predictions, we quantified population structure related to habitat using a genotyping array to assess variation in 42 036 single-nucleotide polymorphisms (SNPs) in 111 North American grey wolves. Using these SNP data and individual-level measurements of 12 environmental variables, we identified six ecotypes: West Forest, Boreal Forest, Arctic, High Arctic, British Columbia and Atlantic Forest. Next, we explored signals of selection across these wolf ecotypes through the use of three complementary methods to detect selection: FST /haplotype homozygosity bivariate percentilae, bayescan, and environmentally correlated directional selection with bayenv. Across all methods, we found consistent signals of selection on genes related to morphology, coat coloration, metabolism, as predicted, as well as vision and hearing. In several high-ranking candidate genes, including LEPR, TYR and SLC14A2, we found variation in allele frequencies that follow environmental changes in temperature and precipitation, a result that is consistent with local adaptation rather than genetic drift. Our findings show that local adaptation can occur despite gene flow in a highly mobile species and can be detected through a moderately dense genomic scan. These patterns of local adaptation revealed by SNP genotyping likely reflect high fidelity to natal habitats of dispersing wolves, strong ecological divergence among habitats, and moderate levels of linkage in the wolf genome. © 2015 John Wiley & Sons Ltd.
Involvement of Superoxide Dismutase in Spore Coat Assembly in Bacillus subtilis
Henriques, Adriano O.; Melsen, Lawrence R.; Moran, Charles P.
1998-01-01
Endospores of Bacillus subtilis are enclosed in a proteinaceous coat which can be differentiated into a thick, striated outer layer and a thinner, lamellar inner layer. We found that the N-terminal sequence of a 25-kDa protein present in a preparation of spore coat proteins matched that of the Mn-dependent superoxide dismutase (SOD) encoded by the sodA locus. sodA is transcribed throughout the growth and sporulation of a wild-type strain and is responsible for the SOD activity detected in total cell extracts prepared from B. subtilis. Disruption of the sodA locus produced a mutant that lacked any detectable SOD activity during vegetative growth and sporulation. The sodA mutant was not impaired in the ability to form heat- or lysozyme-resistant spores. However, examination of the coat layers of sodA mutant spores revealed increased extractability of the tyrosine-rich outer coat protein CotG. We showed that this condition was not accompanied by augmented transcription of the cotG gene in sporulating cells of the sodA mutant. We conclude that SodA is required for the assembly of CotG into the insoluble matrix of the spore and suggest that CotG is covalently cross-linked into the insoluble matrix by an oxidative reaction dependent on SodA. Ultrastructural analysis revealed that the inner coat formed by a sodA mutant was incomplete. Moreover, the outer coat lacked the characteristic striated appearance of wild-type spores, a pattern that was accentuated in a cotG mutant. These observations suggest that the SodA-dependent formation of the insoluble matrix containing CotG is largely responsible for the striated appearance of this coat layer. PMID:9573176
Käosaar, Sandra; Kahru, Anne; Mantecca, Paride; Kasemets, Kaja
2016-09-01
The widespread use of nanosilver in various antibacterial, antifungal, and antiviral products warrants the studies of the toxicity pathways of nanosilver-enabled materials toward microbes and viruses. We profiled the toxicity mechanisms of uncoated, casein-coated, and polyvinylpyrrolidone-coated silver nanoparticles (AgNPs) using Saccharomyces cerevisiae wild-type (wt) and its 9 single-gene deletion mutants defective in oxidative stress (OS) defense, cell wall/membrane integrity, and endocytosis. The 48-h growth inhibition assay in organic-rich growth medium and 24-h cell viability assay in deionized (DI) water were applied whereas AgNO3, H2O2, and SDS served as positive controls. Both coated AgNPs (primary size 8-12nm) were significantly more toxic than the uncoated (~85nm) AgNPs. All studied AgNPs were ~30 times more toxic if exposed to yeast cells in DI water than in the rich growth medium: the IC50 based on nominal concentration of AgNPs in the growth inhibition test ranged from 77 to 576mg Ag/L and in the cell viability test from 2.7 to 18.7mg Ag/L, respectively. Confocal microscopy showed that wt but not endocytosis mutant (end3Δ) internalized AgNPs. Comparison of toxicity patterns of wt and mutant strains defective in OS defense and membrane integrity revealed that the toxicity of the studied AgNPs to S. cerevisiae was not caused by the OS or cell wall/membrane permeabilization. Copyright © 2016 Elsevier Ltd. All rights reserved.
Metagenomic analysis of microbial communities yields insight into impacts of nanoparticle design
NASA Astrophysics Data System (ADS)
Metch, Jacob W.; Burrows, Nathan D.; Murphy, Catherine J.; Pruden, Amy; Vikesland, Peter J.
2018-01-01
Next-generation DNA sequencing and metagenomic analysis provide powerful tools for the environmentally friendly design of nanoparticles. Herein we demonstrate this approach using a model community of environmental microbes (that is, wastewater-activated sludge) dosed with gold nanoparticles of varying surface coatings and morphologies. Metagenomic analysis was highly sensitive in detecting the microbial community response to gold nanospheres and nanorods with either cetyltrimethylammonium bromide or polyacrylic acid surface coatings. We observed that the gold-nanoparticle morphology imposes a stronger force in shaping the microbial community structure than does the surface coating. Trends were consistent in terms of the compositions of both taxonomic and functional genes, which include antibiotic resistance genes, metal resistance genes and gene-transfer elements associated with cell stress that are relevant to public health. Given that nanoparticle morphology remained constant, the potential influence of gold dissolution was minimal. Surface coating governed the nanoparticle partitioning between the bioparticulate and aqueous phases.
Coats' disease and congenital retinoschisis in a single eye: a case report and DNA analysis.
Berinstein, D M; Hiraoka, M; Trese, M T; Shastry, B S
2001-01-01
The clinical features of Coats' disease and congenital retinoschisis (RS) are distinctly different. Therefore, finding changes consistent with Coats' disease and congenital RS in a single eye is an unusual occurrence. The following report describes two cases with a Coats' telangiectatic lesion in one region of the retina separated by normal retina and the presence of central and peripheral congenital RS. Molecular genetic analysis of the Norrie disease and RS genes failed to identify disease-causing or polymorphic mutations in either of the genes, suggesting that the above condition is clinically and genetically a different disorder. Further studies are needed to identify the genes responsible for the above disorder and associated ocular manifestations. Copyright 2001 S. Karger AG, Basel.
Williams, Lucy H.; Kalantry, Sundeep; Starmer, Joshua; Magnuson, Terry
2011-01-01
Repression of Xist RNA expression is considered a prerequisite to reversal of X-chromosome inactivation (XCI) in the mouse inner cell mass (ICM), and reactivation of X-linked genes is thought to follow loss of Xist RNA coating and heterochromatic markers of inactivation, such as methylation of histone H3. We analyzed X-chromosome activity in developing ICMs and show that reactivation of gene expression from the inactive-X initiates in the presence of Xist coating and H3K27me3. Furthermore, depletion of Xist RNA coating through forced upregulation of NANOG does not result in altered reactivation kinetics. Taken together, our observations suggest that in the ICM, X-linked gene transcription and Xist coating are uncoupled. These data fundamentally alter our perception of the reactivation process and support the existence of a mechanism to reactivate Xp-linked genes in the ICM that operates independently of loss of Xist RNA and H3K27me3 from the imprinted inactive-X. PMID:21471155
Chen, Shi-Yi; Huang, Yi; Zhu, Qing; Fontanesi, Luca; Yao, Yong-Gang; Liu, Yi-Ping
2009-01-01
Melanocortin 1 receptor (MC1R) gene plays a key role in determining coat color in several species, including the cattle. However, up to now there is no report regarding the MC1R gene and the potential association of its mutations with coat colors in yak (Poephagus grunniens). In this study, we sequenced the encoding region of the MC1R gene in three yak breeds with completely white (Tianzhu breed) or black coat color (Jiulong and Maiwa breeds). The predicted coding region of the yak MC1R gene resulted of 954 bp, the same to that of the wild-type cattle sequence, with >99% identity. None of the mutation events reported in cattle was found. Comparing the yak obtained sequences, five nucleotide substitutions were detected, which defined three haplotypes (EY1, EY2, and EY3). Of the five mutations, two, characterizing the EY1 haplotype, were nonsynonymous substitutions (c.340C>A and c.871G>A) causing amino acid changes located in the first extracellular loop (p.Q114K) and in the seventh transmembrane region (p.A291T). In silico prediction might indicate a functional effect of the latter substitution. However, all three haplotypes were present in the three yak breeds with relatively consistent frequency distribution, despite of their distinguished coat colors, which suggested that there was no across-breed association between haplotypes or genotypes and black/white phenotypes, at least in the investigated breeds. Other genes may be involved in affecting coat color in the analyzed yaks. PMID:19584942
NASA Astrophysics Data System (ADS)
Lenhart, Joseph L.; Fischer, Daniel; Sambasivan, Sharadha; Lin, Eric K.; Wu, Wen-Li; Guerrero, Douglas J.; Wang, Yubao; Puligadda, Rama
2007-02-01
Interactions between a bottom anti-reflective coating (BARC) and a photoresist can critically impact lithographic patterns. For example, a lithographic pattern can shrink or spread near a BARC interface, a process called undercutting or footing respectively, due to incompatibility between the two materials. Experiments were conducted on two industrial BARC coatings in an effort to determine the impact of BARC surface chemistry on the footing and undercutting phenomena. The BARC coatings were characterized by near edge X-ray absorption fine structure (NEXAFS), contact angle measurements, and neutron and X-ray reflectivity. Contact angle measurement using a variety of fluids showed that the fluid contact angles were independent of the type of BARC coating or the BARC processing temperature. NEXAFS measurements showed that the surface chemistry of each BARC was also independent of the processing temperature. These results suggest that acid-base interactions at the BARC-resist interface are not the cause of the footing-undercutting phenomena encountered in lithographic patterns.
Gershony, L C; Penedo, M C T; Davis, B W; Murphy, W J; Helps, C R; Lyons, L A
2014-12-01
Coat colours and patterns are highly variable in cats and are determined mainly by several genes with Mendelian inheritance. A 2-bp deletion in agouti signalling protein (ASIP) is associated with melanism in domestic cats. Bengal cats are hybrids between domestic cats and Asian leopard cats (Prionailurus bengalensis), and the charcoal coat colouration/pattern in Bengals presents as a possible incomplete melanism. The complete coding region of ASIP was directly sequenced in Asian leopard, domestic and Bengal cats. Twenty-seven variants were identified between domestic and leopard cats and were investigated in Bengals and Savannahs, a hybrid with servals (Leptailurus serval). The leopard cat ASIP haplotype was distinguished from domestic cat by four synonymous and four non-synonymous exonic SNPs, as well as 19 intronic variants, including a 42-bp deletion in intron 4. Fifty-six of 64 reported charcoal cats were compound heterozygotes at ASIP, with leopard cat agouti (A(P) (be) ) and domestic cat non-agouti (a) haplotypes. Twenty-four Bengals had an additional unique haplotype (A2) for exon 2 that was not identified in leopard cats, servals or jungle cats (Felis chaus). The compound heterozygote state suggests the leopard cat allele, in combination with the recessive non-agouti allele, influences Bengal markings, producing a darker, yet not completely melanistic coat. This is the first validation of a leopard cat allele segregating in the Bengal breed and likely affecting their overall pelage phenotype. Genetic testing services need to be aware of the possible segregation of wild felid alleles in all assays performed on hybrid cats. © 2014 The Authors. Animal Genetics published by John Wiley & Sons Ltd on behalf of Stichting International Foundation for Animal Genetics.
Vogt, Carmen; Pernemalm, Maria; Kohonen, Pekka; Laurent, Sophie; Hultenby, Kjell; Vahter, Marie; Lehtiö, Janne; Toprak, Muhammet S.; Fadeel, Bengt
2015-01-01
Superparamagnetic iron oxide nanoparticles (SPIONs) have emerged as promising contrast agents for magnetic resonance imaging. The influence of different surface coatings on the biocompatibility of SPIONs has been addressed, but the potential impact of the so-called corona of adsorbed proteins on the surface of SPIONs on their biological behavior is less well studied. Here, we determined the composition of the plasma protein corona on silica-coated versus dextran-coated SPIONs using mass spectrometry-based proteomics approaches. Notably, gene ontology (GO) enrichment analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis revealed distinct protein corona compositions for the two different SPIONs. Relaxivity of silica-coated SPIONs was modulated by the presence of a protein corona. Moreover, the viability of primary human monocyte-derived macrophages was influenced by the protein corona on silica-coated, but not dextran-coated SPIONs, and the protein corona promoted cellular uptake of silica-coated SPIONs, but did not affect internalization of dextran-coated SPIONs. PMID:26444829
Vogt, Carmen; Pernemalm, Maria; Kohonen, Pekka; Laurent, Sophie; Hultenby, Kjell; Vahter, Marie; Lehtiö, Janne; Toprak, Muhammet S; Fadeel, Bengt
2015-01-01
Superparamagnetic iron oxide nanoparticles (SPIONs) have emerged as promising contrast agents for magnetic resonance imaging. The influence of different surface coatings on the biocompatibility of SPIONs has been addressed, but the potential impact of the so-called corona of adsorbed proteins on the surface of SPIONs on their biological behavior is less well studied. Here, we determined the composition of the plasma protein corona on silica-coated versus dextran-coated SPIONs using mass spectrometry-based proteomics approaches. Notably, gene ontology (GO) enrichment analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis revealed distinct protein corona compositions for the two different SPIONs. Relaxivity of silica-coated SPIONs was modulated by the presence of a protein corona. Moreover, the viability of primary human monocyte-derived macrophages was influenced by the protein corona on silica-coated, but not dextran-coated SPIONs, and the protein corona promoted cellular uptake of silica-coated SPIONs, but did not affect internalization of dextran-coated SPIONs.
Prevalence of deafness and association with coat variations in client-owned ferrets.
Piazza, Stéphanie; Abitbol, Marie; Gnirs, Kirsten; Huynh, Minh; Cauzinille, Laurent
2014-05-01
To evaluate the prevalence of congenital sensorineural deafness (CSD) and its association with phenotypic markers in client-owned ferrets. Epidemiological study. 152 healthy European pet ferrets. Brainstem auditory evoked response tests were recorded in ferrets during general anesthesia. Phenotypic markers such as sex, coat color and pattern, coat length (Angora or not), and premature graying trait were assessed. Overall, 44 of the 152 (29%) ferrets were affected by CSD; 10 (7%) were unilaterally deaf, and 34 (22%) were bilaterally deaf. There was no association between CSD and sex or Angora trait, but a strong association between CSD and white patterned coat or premature graying was identified. All panda, American panda, and blaze ferrets were deaf. The ferrets in this study had a high prevalence of CSD that was strictly associated with coat color patterns, specifically white markings and premature graying. This seemed to be an emerging congenital defect in pet ferrets because white-marked coats are a popular new coat color. Breeders should have a greater awareness and understanding of this defect to reduce its prevalence for the overall benefit of the species.
Mutations in MITF and PAX3 cause "splashed white" and other white spotting phenotypes in horses.
Hauswirth, Regula; Haase, Bianca; Blatter, Marlis; Brooks, Samantha A; Burger, Dominik; Drögemüller, Cord; Gerber, Vincent; Henke, Diana; Janda, Jozef; Jude, Rony; Magdesian, K Gary; Matthews, Jacqueline M; Poncet, Pierre-André; Svansson, Vilhjálmur; Tozaki, Teruaki; Wilkinson-White, Lorna; Penedo, M Cecilia T; Rieder, Stefan; Leeb, Tosso
2012-01-01
During fetal development neural-crest-derived melanoblasts migrate across the entire body surface and differentiate into melanocytes, the pigment-producing cells. Alterations in this precisely regulated process can lead to white spotting patterns. White spotting patterns in horses are a complex trait with a large phenotypic variance ranging from minimal white markings up to completely white horses. The "splashed white" pattern is primarily characterized by an extremely large blaze, often accompanied by extended white markings at the distal limbs and blue eyes. Some, but not all, splashed white horses are deaf. We analyzed a Quarter Horse family segregating for the splashed white coat color. Genome-wide linkage analysis in 31 horses gave a positive LOD score of 1.6 in a region on chromosome 6 containing the PAX3 gene. However, the linkage data were not in agreement with a monogenic inheritance of a single fully penetrant mutation. We sequenced the PAX3 gene and identified a missense mutation in some, but not all, splashed white Quarter Horses. Genome-wide association analysis indicated a potential second signal near MITF. We therefore sequenced the MITF gene and found a 10 bp insertion in the melanocyte-specific promoter. The MITF promoter variant was present in some splashed white Quarter Horses from the studied family, but also in splashed white horses from other horse breeds. Finally, we identified two additional non-synonymous mutations in the MITF gene in unrelated horses with white spotting phenotypes. Thus, several independent mutations in MITF and PAX3 together with known variants in the EDNRB and KIT genes explain a large proportion of horses with the more extreme white spotting phenotypes.
Mutations in MITF and PAX3 Cause “Splashed White” and Other White Spotting Phenotypes in Horses
Blatter, Marlis; Brooks, Samantha A.; Burger, Dominik; Drögemüller, Cord; Gerber, Vincent; Henke, Diana; Janda, Jozef; Jude, Rony; Magdesian, K. Gary; Matthews, Jacqueline M.; Poncet, Pierre-André; Svansson, Vilhjálmur; Tozaki, Teruaki; Wilkinson-White, Lorna; Penedo, M. Cecilia T.; Rieder, Stefan; Leeb, Tosso
2012-01-01
During fetal development neural-crest-derived melanoblasts migrate across the entire body surface and differentiate into melanocytes, the pigment-producing cells. Alterations in this precisely regulated process can lead to white spotting patterns. White spotting patterns in horses are a complex trait with a large phenotypic variance ranging from minimal white markings up to completely white horses. The “splashed white” pattern is primarily characterized by an extremely large blaze, often accompanied by extended white markings at the distal limbs and blue eyes. Some, but not all, splashed white horses are deaf. We analyzed a Quarter Horse family segregating for the splashed white coat color. Genome-wide linkage analysis in 31 horses gave a positive LOD score of 1.6 in a region on chromosome 6 containing the PAX3 gene. However, the linkage data were not in agreement with a monogenic inheritance of a single fully penetrant mutation. We sequenced the PAX3 gene and identified a missense mutation in some, but not all, splashed white Quarter Horses. Genome-wide association analysis indicated a potential second signal near MITF. We therefore sequenced the MITF gene and found a 10 bp insertion in the melanocyte-specific promoter. The MITF promoter variant was present in some splashed white Quarter Horses from the studied family, but also in splashed white horses from other horse breeds. Finally, we identified two additional non-synonymous mutations in the MITF gene in unrelated horses with white spotting phenotypes. Thus, several independent mutations in MITF and PAX3 together with known variants in the EDNRB and KIT genes explain a large proportion of horses with the more extreme white spotting phenotypes. PMID:22511888
Fang, Jingjing; Ramsay, Aïna; Renouard, Sullivan; Hano, Christophe; Lamblin, Frédéric; Chabbert, Brigitte; Mesnard, François; Schneider, Bernd
2016-01-01
The concentration of secoisolariciresinol diglucoside (SDG) found in flaxseed ( Linum usitatissimum L.) is higher than that found in any other plant. It exists in flaxseed coats as an SDG-3-hydroxy-3-methylglutaric acid oligomer complex. A laser microdissection method was applied to harvest material from different cell layers of seed coats of mature and developing flaxseed to detect the cell-layer specific localization of SDG in flaxseed; NMR and HPLC were used to identify and quantify SDG in dissected cell layers after alkaline hydrolysis. The obtained results were further confirmed by a standard molecular method. The promoter of one pinoresinol-lariciresinol reductase gene of L. usitatissimum ( LuPLR1 ), which is a key gene involved in SDG biosynthesis, was fused to a β-glucuronidase ( GUS ) reporter gene, and the spatio-temporal regulation of LuPLR1 gene expression in flaxseed was determined by histochemical and activity assays of GUS . The result showed that SDG was synthesized and accumulated in the parenchymatous cell layer of the outer integument of flaxseed coats.
Fang, Jingjing; Ramsay, Aïna; Renouard, Sullivan; Hano, Christophe; Lamblin, Frédéric; Chabbert, Brigitte; Mesnard, François; Schneider, Bernd
2016-01-01
The concentration of secoisolariciresinol diglucoside (SDG) found in flaxseed (Linum usitatissimum L.) is higher than that found in any other plant. It exists in flaxseed coats as an SDG-3-hydroxy-3-methylglutaric acid oligomer complex. A laser microdissection method was applied to harvest material from different cell layers of seed coats of mature and developing flaxseed to detect the cell-layer specific localization of SDG in flaxseed; NMR and HPLC were used to identify and quantify SDG in dissected cell layers after alkaline hydrolysis. The obtained results were further confirmed by a standard molecular method. The promoter of one pinoresinol-lariciresinol reductase gene of L. usitatissimum (LuPLR1), which is a key gene involved in SDG biosynthesis, was fused to a β-glucuronidase (GUS) reporter gene, and the spatio-temporal regulation of LuPLR1 gene expression in flaxseed was determined by histochemical and activity assays of GUS. The result showed that SDG was synthesized and accumulated in the parenchymatous cell layer of the outer integument of flaxseed coats. PMID:27917190
Electrostatic Surface Modifications to Improve Gene Delivery
Shmueli, Ron B.; Anderson, Daniel G.
2010-01-01
Importance of the field Gene therapy has the potential to treat a wide variety of diseases including genetic diseases and cancer. Areas covered in this review This review introduces biomaterials used for gene delivery and then focuses on the use of electrostatic surface modifications to improve gene delivery materials. These modifications have been used to stabilize therapeutics in vivo, add cell-specific targeting ligands, and promote controlled release. Coatings of nanoparticles and microparticles as well as non-particulate surface coatings are covered in this review. Electrostatic principles are crucial for the development of multilayer delivery structures fabricated by the layer-by-layer method. What the reader will gain The reader will gain knowledge about the composition of biomaterials used for surface modifications and how these coatings and multilayers can be utilized to improve spatial control and efficiency of delivery. Examples are shown for the delivery of nucleic acids, including DNA and siRNA, to in vitro and in vivo systems. Take home message The versatile and powerful approach of electrostatic coatings and multilayers will lead to the development of enhanced gene therapies. PMID:20201712
Ruan, Y. L.; Chourey, P. S.; Delmer, D. P.; Perez-Grau, L.
1997-01-01
Developing cotton (Gossypium hirsutum L.) seed exhibits complex patterns of carbon allocation in which incoming sucrose (Suc) is partitioned to three major sinks: the fibers, seed coat, and cotyledons, which synthesize cellulose, starch, and storage proteins or oils, respectively. In this study we investigated the role of Suc synthase (SuSy) in the mobilization of Suc into such sinks. Assessments of SuSy gene expression at various levels led to the surprising conclusion that, in contrast to that found for other plants, SuSy does not appear to play a role in starch synthesis in the cotton seed. However, our demonstration of functional symplastic connections between the phloem-unloading area and the fiber cells, as well as the SuSy expression pattern in fibers, indicates a major role of SuSy in partitioning carbon to fiber cellulose synthesis. SuSy expression is also high in transfer cells of the seed coat facing the cotyledons. Such high levels of SuSy could contribute to the synthesis of the thickened cell walls and to the energy generation for Suc efflux to the seed apoplast. The expression of SuSy in cotyledons also suggests a role in protein and lipid synthesis. In summary, the developing cotton seed provides an excellent example of the diverse roles played by SuSy in carbon metabolism. PMID:12223814
NASA Astrophysics Data System (ADS)
Xiang, Youlai; Du, Ai; Li, Xiaoguang; Sun, Wei; Wu, Shuai; Li, Tiemin; Liu, Mingfang; Zhou, Bin
2017-07-01
Photosensitive ZrO2-SiO2 hybrid sol-gel coatings containing large contents of chelating rings were prepared by using the zirconium n-butoxide (TBOZ) and methyltriethoxysilane (MTES) as hybrid precursors, and benzoylacetone (BZAC) as chelating agent. The change of ultraviolet (UV) absorption spectra, chemical composition, and optical properties of ZrO2-SiO2 hybrid sol-gel coatings were analyzed before and after UV exposure and calcination. The refractive index of the ZrO2-SiO2 hybrid gel coatings decreased from 1.673 to 1.561 with the increase of the molar content of MTES in precursors. The sol-gel coating patterns with the periods of 20.24 μm, 10.11 μm and 3.99 μm on the PAMS substrates were firstly obtained by using the photosensitive ZrO2-SiO2 hybrid sol-gel films as fundamental materials through a process of UV contact lithography with photo masks and etching with ethanol. Finally, the free-standing gel coating patterns supported by copper grids, with the period of 12.70 μm and line width of 4.93 μm, and the period of 14.20 μm and line width of 3.82 μm, were obtained by removing the PAMS thermal degradation sacrifice layer after being calcined at 330 °C. Micrometer-periodic free-standing gel coating patterns with different structure have potential applications in the laser physical experiments.
Intravascular local gene transfer mediated by protein-coated metallic stent.
Yuan, J; Gao, R; Shi, R; Song, L; Tang, J; Li, Y; Tang, C; Meng, L; Yuan, W; Chen, Z
2001-10-01
To assess the feasibility, efficiency and selectivity of adenovirus-mediated gene transfer to local arterial wall by protein-coated metallic stent. A replication-defective recombinant adenovirus carrying the Lac Z reporter gene for nuclear-specific beta-galactosidase (Ad-beta gal) was used in this study. The coating for metallic stent was made by immersing it in a gelatin solution containing crosslinker. The coated stents were mounted on a 4.0 or 3.0 mm percutaneous transluminal coronary angioplasty (PTCA) balloon and submersed into a high-titer Ad-beta gal viral stock (2 x 10(10) pfu/ml) for 3 min, and then implanted into the carotid arteries in 4 mini-swines and into the left anterior descending branch of the coronary artery in 2 mini-swines via 8F large lumen guiding catheters. The animals were sacrificed 7 (n = 4), 14 (n = 1) and 21 (n = 1) days after implantation, respectively. The beta-galactosidase expression was assessed by X-gal staining. The results showed that the expression of transgene was detected in all animal. In 1 of carotid artery with an intact intima, the beta-gal expression was limited to endothelial cells. In vessels with denuded endothelium, gene expression was found in the sub-intima, media and adventitia. The transfection efficiency of medial smooth muscle cells was 38.6%. In 2 animals sacrificed 7 days after transfection, a microscopic examination of X-gal-stained samples did not show evidence of transfection in remote organs and arterial segments adjacent to the treated arterial site. Adenovirus-mediated arterial gene transfer to endothelial, smooth muscle cells and adventitia by protein-coated metallic stent is feasible. The transfection efficiency is higher. The coated stent may act as a good carrier of adenovirus-mediated gene transfer and have a potential to prevent restenosis following PTCA.
Huson, Heather J.; Kim, Eui-Soo; Godfrey, Robert W.; Olson, Timothy A.; McClure, Matthew C.; Chase, Chad C.; Rizzi, Rita; O'Brien, Ana M. P.; Van Tassell, Curt P.; Garcia, José F.; Sonstegard, Tad S.
2014-01-01
The slick hair coat (SLICK) is a dominantly inherited trait typically associated with tropically adapted cattle that are from Criollo descent through Spanish colonization of cattle into the New World. The trait is of interest relative to climate change, due to its association with improved thermo-tolerance and subsequent increased productivity. Previous studies localized the SLICK locus to a 4 cM region on chromosome (BTA) 20 and identified signatures of selection in this region derived from Senepol cattle. The current study compares three slick-haired Criollo-derived breeds including Senepol, Carora, and Romosinuano and three additional slick-haired cross-bred lineages to non-slick ancestral breeds. Genome-wide association (GWA), haplotype analysis, signatures of selection, runs of homozygosity (ROH), and identity by state (IBS) calculations were used to identify a 0.8 Mb (37.7–38.5 Mb) consensus region for the SLICK locus on BTA20 in which contains SKP2 and SPEF2 as possible candidate genes. Three specific haplotype patterns are identified in slick individuals, all with zero frequency in non-slick individuals. Admixture analysis identified common genetic patterns between the three slick breeds at the SLICK locus. Principal component analysis (PCA) and admixture results show Senepol and Romosinuano sharing a higher degree of genetic similarity to one another with a much lesser degree of similarity to Carora. Variation in GWA, haplotype analysis, and IBS calculations with accompanying population structure information supports potentially two mutations, one common to Senepol and Romosinuano and another in Carora, effecting genes contained within our refined location for the SLICK locus. PMID:24808908
Huson, Heather J; Kim, Eui-Soo; Godfrey, Robert W; Olson, Timothy A; McClure, Matthew C; Chase, Chad C; Rizzi, Rita; O'Brien, Ana M P; Van Tassell, Curt P; Garcia, José F; Sonstegard, Tad S
2014-01-01
The slick hair coat (SLICK) is a dominantly inherited trait typically associated with tropically adapted cattle that are from Criollo descent through Spanish colonization of cattle into the New World. The trait is of interest relative to climate change, due to its association with improved thermo-tolerance and subsequent increased productivity. Previous studies localized the SLICK locus to a 4 cM region on chromosome (BTA) 20 and identified signatures of selection in this region derived from Senepol cattle. The current study compares three slick-haired Criollo-derived breeds including Senepol, Carora, and Romosinuano and three additional slick-haired cross-bred lineages to non-slick ancestral breeds. Genome-wide association (GWA), haplotype analysis, signatures of selection, runs of homozygosity (ROH), and identity by state (IBS) calculations were used to identify a 0.8 Mb (37.7-38.5 Mb) consensus region for the SLICK locus on BTA20 in which contains SKP2 and SPEF2 as possible candidate genes. Three specific haplotype patterns are identified in slick individuals, all with zero frequency in non-slick individuals. Admixture analysis identified common genetic patterns between the three slick breeds at the SLICK locus. Principal component analysis (PCA) and admixture results show Senepol and Romosinuano sharing a higher degree of genetic similarity to one another with a much lesser degree of similarity to Carora. Variation in GWA, haplotype analysis, and IBS calculations with accompanying population structure information supports potentially two mutations, one common to Senepol and Romosinuano and another in Carora, effecting genes contained within our refined location for the SLICK locus.
Coating and Patterning Functional Materials for Large Area Electrofluidic Arrays
Wu, Hao; Tang, Biao; Hayes, Robert A.; Dou, Yingying; Guo, Yuanyuan; Jiang, Hongwei; Zhou, Guofu
2016-01-01
Industrialization of electrofluidic devices requires both high performance coating laminates and efficient material utilization on large area substrates. Here we show that screen printing can be effectively used to provide homogeneous pin-hole free patterned amorphous fluoropolymer dielectric layers to provide both the insulating and fluidic reversibility required for devices. Subsequently, we over-coat photoresist using slit coating on this normally extremely hydrophobic layer. In this way, we are able to pattern the photoresist by conventional lithography to provide the chemical contrast required for liquids dosing by self-assembly and highly-reversible electrofluidic switching. Materials, interfacial chemistry, and processing all contribute to the provision of the required engineered substrate properties. Coating homogeneity as characterized by metrology and device performance data are used to validate the methodology, which is well-suited for transfer to high volume production in existing LCD cell-making facilities. PMID:28773826
Coating and Patterning Functional Materials for Large Area Electrofluidic Arrays.
Wu, Hao; Tang, Biao; Hayes, Robert A; Dou, Yingying; Guo, Yuanyuan; Jiang, Hongwei; Zhou, Guofu
2016-08-19
Industrialization of electrofluidic devices requires both high performance coating laminates and efficient material utilization on large area substrates. Here we show that screen printing can be effectively used to provide homogeneous pin-hole free patterned amorphous fluoropolymer dielectric layers to provide both the insulating and fluidic reversibility required for devices. Subsequently, we over-coat photoresist using slit coating on this normally extremely hydrophobic layer. In this way, we are able to pattern the photoresist by conventional lithography to provide the chemical contrast required for liquids dosing by self-assembly and highly-reversible electrofluidic switching. Materials, interfacial chemistry, and processing all contribute to the provision of the required engineered substrate properties. Coating homogeneity as characterized by metrology and device performance data are used to validate the methodology, which is well-suited for transfer to high volume production in existing LCD cell-making facilities.
Taming contact line instability for pattern formation
Deblais, A.; Harich, R.; Colin, A.; Kellay, H.
2016-01-01
Coating surfaces with different fluids is prone to instability producing inhomogeneous films and patterns. The contact line between the coating fluid and the surface to be coated is host to different instabilities, limiting the use of a variety of coating techniques. Here we take advantage of the instability of a receding contact line towards cusp and droplet formation to produce linear patterns of variable spacings. We stabilize the instability of the cusps towards droplet formation by using polymer solutions that inhibit this secondary instability and give rise to long slender cylindrical filaments. We vary the speed of deposition to change the spacing between these filaments. The combination of the two gives rise to linear patterns into which different colloidal particles can be embedded, long DNA molecules can be stretched and particles filtered by size. The technique is therefore suitable to prepare anisotropic structures with variable properties. PMID:27506626
Taming contact line instability for pattern formation.
Deblais, A; Harich, R; Colin, A; Kellay, H
2016-08-10
Coating surfaces with different fluids is prone to instability producing inhomogeneous films and patterns. The contact line between the coating fluid and the surface to be coated is host to different instabilities, limiting the use of a variety of coating techniques. Here we take advantage of the instability of a receding contact line towards cusp and droplet formation to produce linear patterns of variable spacings. We stabilize the instability of the cusps towards droplet formation by using polymer solutions that inhibit this secondary instability and give rise to long slender cylindrical filaments. We vary the speed of deposition to change the spacing between these filaments. The combination of the two gives rise to linear patterns into which different colloidal particles can be embedded, long DNA molecules can be stretched and particles filtered by size. The technique is therefore suitable to prepare anisotropic structures with variable properties.
Laser induced heating of coated carbon steel sheets: Consideration of melting and Marangoni flow
NASA Astrophysics Data System (ADS)
Shuja, S. Z.; Yilbas, B. S.
2013-04-01
Laser induced melting of coated carbon steel workpiece is simulated. The coating materials include tungsten carbide, alumina, and boron are incorporated in the simulations. The coating thickness is kept constant at 7.5 μm in the analysis. The enthalpy porosity method is used to account for the phase change in the irradiated region. The study is extended to include the influence of laser intensity transverse mode pattern (β) on the resulting melting characteristics. It is found that peak temperature predicted at the surface is higher for alumina and boron coatings than that of tungsten carbide coating. The influence of the laser intensity transverse mode pattern on the melting characteristics is considerable. Surface temperature predicted agrees with the thermocouple data.
NASA Technical Reports Server (NTRS)
Smith, W. O.; Toft, A. R. (Inventor)
1973-01-01
A method for the production of reticles, particularly those for use in outer space, where the product is a quartz base coated with highly adherent layers of chromium, chromium-silver, and silver vacuum deposited through a mask, and then coated with an electrodeposit of copper from a copper sulfate solution followed by an electrodeposit of black chromium is described. The masks are produced by coating a beryllium-copper alloy substrate with a positive working photoresist, developing the photoresist, according to a pattern to leave a positive mask, plating uncoated areas with gold, removing the photoresist, coating the substrate with a negative working photoresist, developing the negative working photoresist to expose the base metal of the pattern, and chemically etching the unplated side of the pattern to produce the mask.
Grünwald, Geoffrey K; Vetter, Alexandra; Klutz, Kathrin; Willhauck, Michael J; Schwenk, Nathalie; Senekowitsch-Schmidtke, Reingard; Schwaiger, Markus; Zach, Christian; Wagner, Ernst; Göke, Burkhard; Holm, Per S; Ogris, Manfred; Spitzweg, Christine
2013-01-01
We recently demonstrated tumor-selective iodide uptake and therapeutic efficacy of combined radiovirotherapy after systemic delivery of the theranostic sodium iodide symporter (NIS) gene using a dendrimer-coated adenovirus. To further improve shielding and targeting we physically coated replication-selective adenoviruses carrying the hNIS gene with a conjugate consisting of cationic poly(amidoamine) (PAMAM) dendrimer linked to the peptidic, epidermal growth factor receptor (EGFR)-specific ligand GE11. In vitro experiments demonstrated coxsackie-adenovirus receptor-independent but EGFR-specific transduction efficiency. Systemic injection of the uncoated adenovirus in a liver cancer xenograft mouse model led to high levels of NIS expression in the liver due to hepatic sequestration, which were significantly reduced after coating as demonstrated by 123I-scintigraphy. Reduction of adenovirus liver pooling resulted in decreased hepatotoxicity and increased transduction efficiency in peripheral xenograft tumors. 124I-PET-imaging confirmed EGFR-specificity by significantly lower tumoral radioiodine accumulation after pretreatment with the EGFR-specific antibody cetuximab. A significantly enhanced oncolytic effect was observed following systemic application of dendrimer-coated adenovirus that was further increased by additional treatment with a therapeutic dose of 131I. These results demonstrate restricted virus tropism and tumor-selective retargeting after systemic application of coated, EGFR-targeted adenoviruses therefore representing a promising strategy for improved systemic adenoviral NIS gene therapy. PMID:24193032
Plasma Sprayed Hydroxyapatite Coatings: Influence of Spraying Power on Microstructure
NASA Astrophysics Data System (ADS)
Mohd, S. M.; Abd, M. Z.; Abd, A. N.
2010-03-01
The plasma sprayed hydroxyapatite (HA) coatings are used on metallic implants to enhance the bonding between the implant and bone in human body. The coating process was implemented at different spraying power for each spraying condition. The coatings formed from a rapid solidification of molten and partly molten particles that impact on the surface of substrate at high velocity and high temperature. The study was concentrated on different spraying power that is between 23 to 31 kW. The effect of different power on the coatings microstructure was investigated using scanning electron microscope (SEM) and phase composition was evaluated using X-ray diffraction (XRD) analysis. The coatings surface morphology showed distribution of molten, partially melted particles and some micro-cracks. The produced coatings were found to be porous as observed from the cross-sectional morphology. The coatings XRD results indicated the presence of crystalline phase of HA and each of the patterns was similar to the initial powder. Regardless of different spraying power, all the coatings were having similar XRD patterns.
Zhou, C E; Ko, R; Maeda, S
1998-01-20
The polyhedrin gene in Bombyx mori nucleopolyhedrovirus (BmNPV) was replaced with the granulin gene of Trichoplusia ni granulovirus (TnGV). The substitution was verified by Southern hybridization, and expression of granulin by the mutant virus, BmGran, was demonstrated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and by amino acid sequencing of the predominant protein of BmGran inclusion bodies (IBs). Light and electron microscopy examination of BmGran-infected B. mori and BmN cells revealed large, cuboidal, polyhedron-like IBs in the nucleus and cytoplasm, but granules were not seen. IBs contained small, parallel, electron-dense streaks, which defined the geometric pattern of crystallization. Geometric patterns of nuclear IBs were frequently disrupted by occlusion of polyhedron envelope fragments, resulting in IB instability and fracturing. Virions were not embedded in most of the polyhedron-like IBs, but accumulated with polyhedron envelope fragments. Some virions were coated with matrix protein and were partially wrapped by polyhedron envelope. These results suggested that (1) the amino acid sequence of granulin insufficient for determining IB morphology in TnGV-infected cells, and TnGV may have genes, not present in BmNPV, that control granule formation, and (2) interactions among the virion, the IB envelope, and the matrix protein may be important in virion occlusion and IB morphology and stability.
Secure and effective gene delivery system of plasmid DNA coated by polynucleotide.
Kodama, Yukinobu; Ohkubo, Chikako; Kurosaki, Tomoaki; Egashira, Kanoko; Sato, Kayoko; Fumoto, Shintaro; Nishida, Koyo; Higuchi, Norihide; Kitahara, Takashi; Nakamura, Tadahiro; Sasaki, Hitoshi
2015-01-01
Polynucleotides are anionic macromolecules which are expected to transfer into the targeted cells through specific uptake mechanisms. So, we developed polynucleotides coating complexes of plasmid DNA (pDNA) and polyethylenimine (PEI) for a secure and efficient gene delivery system and evaluated their usefulness. Polyadenylic acid (polyA), polyuridylic acid (polyU), polycytidylic acid (polyC), and polyguanylic acid (polyG) were examined as the coating materials. pDNA/PEI/polyA, pDNA/PEI/polyU, and pDNA/PEI/polyC complexes formed nanoparticles with a negative surface charge although pDNA/PEI/polyG was aggregated. The pDNA/PEI/polyC complex showed high transgene efficiency in B16-F10 cells although there was little efficiency in pDNA/PEI/polyA and pDNA/PEI/polyU complexes. An inhibition study strongly indicated the specific uptake mechanism of pDNA/PEI/polyC complex. Polynucleotide coating complexes had lower cytotoxicity than pDNA/PEI complex. The pDNA/PEI/polyC complex showed high gene expression selectively in the spleen after intravenous injection into mice. The pDNA/PEI/polyC complex showed no agglutination with erythrocytes and no acute toxicity although these were observed in pDNA/PEI complex. Thus, we developed polynucleotide coating complexes as novel vectors for clinical gene therapy, and the pDNA/PEI/polyC complex as a useful candidate for a gene delivery system.
Blaho, Miklos; Egri, Adam; Bahidszki, Lea; Kriska, Gyorgy; Hegedus, Ramon; Akesson, Susanne; Horvath, Gabor
2012-01-01
During blood-sucking, female members of the family Tabanidae transmit pathogens of serious diseases and annoy their host animals so strongly that they cannot graze, thus the health of the hosts is drastically reduced. Consequently, a tabanid-resistant coat with appropriate brightness, colour and pattern is advantageous for the host. Spotty coats are widespread among mammals, especially in cattle (Bos primigenius). In field experiments we studied the influence of the size and number of spots on the attractiveness of test surfaces to tabanids that are attracted to linearly polarized light. We measured the reflection-polarization characteristics of living cattle, spotty cattle coats and the used test surfaces. We show here that the smaller and the more numerous the spots, the less attractive the target (host) is to tabanids. We demonstrate that the attractiveness of spotty patterns to tabanids is also reduced if the target exhibits spottiness only in the angle of polarization pattern, while being homogeneous grey with a constant high degree of polarization. Tabanid flies respond strongly to linearly polarized light, and we show that bright and dark parts of cattle coats reflect light with different degrees and angles of polarization that in combination with dark spots on a bright coat surface disrupt the attractiveness to tabanids. This could be one of the possible evolutionary benefits that explains why spotty coat patterns are so widespread in mammals, especially in ungulates, many species of which are tabanid hosts.
Blaho, Miklos; Egri, Adam; Bahidszki, Lea; Kriska, Gyorgy; Hegedus, Ramon; Åkesson, Susanne; Horvath, Gabor
2012-01-01
During blood-sucking, female members of the family Tabanidae transmit pathogens of serious diseases and annoy their host animals so strongly that they cannot graze, thus the health of the hosts is drastically reduced. Consequently, a tabanid-resistant coat with appropriate brightness, colour and pattern is advantageous for the host. Spotty coats are widespread among mammals, especially in cattle (Bos primigenius). In field experiments we studied the influence of the size and number of spots on the attractiveness of test surfaces to tabanids that are attracted to linearly polarized light. We measured the reflection-polarization characteristics of living cattle, spotty cattle coats and the used test surfaces. We show here that the smaller and the more numerous the spots, the less attractive the target (host) is to tabanids. We demonstrate that the attractiveness of spotty patterns to tabanids is also reduced if the target exhibits spottiness only in the angle of polarization pattern, while being homogeneous grey with a constant high degree of polarization. Tabanid flies respond strongly to linearly polarized light, and we show that bright and dark parts of cattle coats reflect light with different degrees and angles of polarization that in combination with dark spots on a bright coat surface disrupt the attractiveness to tabanids. This could be one of the possible evolutionary benefits that explains why spotty coat patterns are so widespread in mammals, especially in ungulates, many species of which are tabanid hosts. PMID:22876282
Heun, Yvonn; Hildebrand, Staffan; Heidsieck, Alexandra; Gleich, Bernhard; Anton, Martina; Pircher, Joachim; Ribeiro, Andrea; Mykhaylyk, Olga; Eberbeck, Dietmar; Wenzel, Daniela; Pfeifer, Alexander; Woernle, Markus; Krötz, Florian; Pohl, Ulrich; Mannell, Hanna
2017-01-01
In the field of vascular gene therapy, targeting systems are promising advancements to improve site-specificity of gene delivery. Here, we studied whether incorporation of magnetic nanoparticles (MNP) with different magnetic properties into ultrasound sensitive microbubbles may represent an efficient way to enable gene targeting in the vascular system after systemic application. Thus, we associated novel silicon oxide-coated magnetic nanoparticle containing microbubbles (SO-Mag MMB) with lentiviral particles carrying therapeutic genes and determined their physico-chemical as well as biological properties compared to MMB coated with polyethylenimine-coated magnetic nanoparticles (PEI-Mag MMB). While there were no differences between both MMB types concerning size and lentivirus binding, SO-Mag MMB exhibited superior characteristics regarding magnetic moment, magnetizability as well as transduction efficiency under static and flow conditions in vitro . Focal disruption of lentiviral SO-Mag MMB by ultrasound within isolated vessels exposed to an external magnetic field decisively improved localized VEGF expression in aortic endothelium ex vivo and enhanced the angiogenic response. Using the same system in vivo , we achieved a highly effective, site-specific lentiviral transgene expression in microvessels of the mouse dorsal skin after arterial injection. Thus, we established a novel lentiviral MMB technique, which has great potential towards site-directed vascular gene therapy.
Lifeng, Zhao; Yan, Hong; Dayun, Yang; Xiaoying, Lü; Tingfei, Xi; Deyuan, Zhang; Ying, Hong; Jinfeng, Yuan
2011-04-01
TiN coating has been demonstrated to improve the biocompatibility of bare NiTi alloys; however, essential biocompatibility differences between NiTi alloys before and after TiN coating are not known so far. In this study, to explore the underlying biological mechanisms of biocompatibility differences between them, the changes of bare and TiN-coated NiTi alloys in surface chemical composition, morphology, hydrophilicity, Ni ions release, cytotoxicity, apoptosis, and gene expression profiles were compared using energy-dispersive spectroscopy, scanning electron microscopy, contact angle, surface energy, Ni ions release analysis, the methylthiazoltetrazolium (MTT) method, flow cytometry and microarray methods, respectively. Pathways binding to networks and real-time polymerase chain reaction (PCR) were employed to analyze and validate the microarray data, respectively. It was found that, compared with the bare NiTi alloys, TiN coating significantly decreased Ni ions content on the surfaces of the NiTi alloys and reduced the release of Ni ions from the alloys, attenuated the inhibition of Ni ions to the expression of genes associated with anti-inflammatory, and also suppressed the promotion of Ni ions to the expression of apoptosis-related genes. Moreover, TiN coating distinctly improved the hydrophilicity and uniformity of the surfaces of the NiTi alloys, and contributed to the expression of genes participating in cell adhesion and other physiological activities. These results indicate that the TiN-coated NiTi alloys will help overcome the shortcomings of NiTi alloys used in clinical application currently, and can be expected to be a replacement of biomaterials for a medical device field.
Piffanelli, P; Ross, J H; Murphy, D J
1997-03-01
Pollen development in angiosperms is regulated by the interaction of products contributed by both the gametophytic (haploid) and sporophytic (diploid) genomes. In entomophilous species, lipids are major products of both sporophytic and gametophytic metabolism during pollen development. Mature pollen grains of Brassica napus are shown to contain three major acyl lipid pools as follows: (i) the extracellular tryphine mainly consisting of medium-chain neutral esters; (ii) the intracellular membranes, particularly endoplasmic reticulum, mainly containing phospholipids; and (iii) the intracellular storage lipids, which are mostly triacylglycerols. This paper reports on the kinetics of accumulation of these lipid classes during pollen maturation and the expression patterns of several lipid biosynthetic genes and their protein products that are differentially regulated in developing microspores/ pollen grains (gametophyte) and tapetal cells (sporophyte) of B. napus. Detailed analysis of three members of the stearoyl-ACP desaturase (sad) gene family by Northern blotting, in situ hybridization and RT-PCR showed that the same individual genes were expressed both in gametophytic and sporophytic tissues, although under different temporal regulation. In the tapetum, maximal expression of two marker genes for lipid biosynthesis (sad and ear) occurred at a bud length of 2-3 mm, and the corresponding gene products SAD and EAR were detected by Western blotting in 3-4 mm buds, coinciding with the maximal rates of tapetal lipid accumulation. These lipids are released following tapetal cell disintegration and are relocated to form the major structural component of the extracellular tryphine layer that coats the mature pollen grain. In contrast, in developing microspores/pollen grains, maximal expression of the lipid marker genes sad, ear, acp and cyb5 was at the 3-5 mm bud stages, with the SAD and EAR gene products detected in 4-7 mm buds. This pattern of expression coincided with accumulation of the intracellular storage and membrane lipid components of pollen. These results suggest that, although the same genes may be expressed in the sporophytic tapetal cells and in gametophytic tissues, they are regulated differentially leading to the production of the various contrasting lipidic structures that are assembled together to give rise to a viable, fertile pollen grain.
Vaishampayan, Ankita; de Jong, Anne; Wight, Darren J.; Kok, Jan; Grohmann, Elisabeth
2018-01-01
Methicillin-resistant Staphylococcus aureus (MRSA) has become an important cause of hospital-acquired infections worldwide. It is one of the most threatening pathogens due to its multi-drug resistance and strong biofilm-forming capacity. Thus, there is an urgent need for novel alternative strategies to combat bacterial infections. Recently, we demonstrated that a novel antimicrobial surface coating, AGXX®, consisting of micro-galvanic elements of the two noble metals, silver and ruthenium, surface-conditioned with ascorbic acid, efficiently inhibits MRSA growth. In this study, we demonstrated that the antimicrobial coating caused a significant reduction in biofilm formation (46%) of the clinical MRSA isolate, S. aureus 04-02981. To understand the molecular mechanism of the antimicrobial coating, we exposed S. aureus 04-02981 for different time-periods to the coating and investigated its molecular response via next-generation RNA-sequencing. A conventional antimicrobial silver coating served as a control. RNA-sequencing demonstrated down-regulation of many biofilm-associated genes and of genes related to virulence of S. aureus. The antimicrobial substance also down-regulated the two-component quorum-sensing system agr suggesting that it might interfere with quorum-sensing while diminishing biofilm formation in S. aureus 04-02981. PMID:29497410
Sun, Yanli; Sun, Yanhua
2016-10-01
Objective To obtain the PP7 bacteriophage-like particles carrying the peptide of prostatic acid phosphatase PAP 114-128 , and prove that they retain the original biological activity. Methods First, the plasmid pETDuet-2PP7 was constructed as follows: the gene of PP7 coat protein dimer was amplified by gene mutation combined with overlapping PCR technology, and inserted into the vector pETDuet-1. Following that, the plasmid pETDuet-2PP7-PAP 114-128 was constructed as follows: the PP7 coat protein gene carrying the coding gene of PAP 114-128 peptide was amplified using PCR, and then inserted into the vector pETDuet-2PP7. Both pETDuet-2PP7 and pETDuet-2PP7-PAP 114-128 were transformed into E.coli and expressed. The expression product was verified by SDS-PAGE, double immunodiffusion assay and ELISA. Results The gene fragment of PP7 coat protein dimer was obtained by overlapping PCR using Ex Taq DNA polymerase, and the antigenicity of its expression product was the same as that of the coat protein of wild-type PP7 bacteriophage. Moreover, the PAP 114-128 peptide epitope that was displayed on the surface of PP7 bacteriophage was identical with the corresponding epitope of natural human PAP, and it was able to induce high levels of antibodies. Conclusion The gene of PP7 coat protein dimer with repeated sequences can be prepared by gene mutation combined with overlapping PCR. Based on this, PP7 bacteriophage-like particles carrying PAP peptide can be prepared, which not only solves the problem of the instability of the peptides, but also lays a foundation for the study on their delivery and function.
Genome-wide identification and evolution of the PIN-FORMED (PIN) gene family in Glycine max.
Liu, Yuan; Wei, Haichao
2017-07-01
Soybean (Glycine max) is one of the most important crop plants. Wild and cultivated soybean varieties have significant differences worth further investigation, such as plant morphology, seed size, and seed coat development; these characters may be related to auxin biology. The PIN gene family encodes essential transport proteins in cell-to-cell auxin transport, but little research on soybean PIN genes (GmPIN genes) has been done, especially with respect to the evolution and differences between wild and cultivated soybean. In this study, we retrieved 23 GmPIN genes from the latest updated G. max genome database; six GmPIN protein sequences were changed compared with the previous database. Based on the Plant Genome Duplication Database, 18 GmPIN genes have been involved in segment duplication. Three pairs of GmPIN genes arose after the second soybean genome duplication, and six occurred after the first genome duplication. The duplicated GmPIN genes retained similar expression patterns. All the duplicated GmPIN genes experienced purifying selection (K a /K s < 1) to prevent accumulation of non-synonymous mutations and thus remained more similar. In addition, we also focused on the artificial selection of the soybean PIN genes. Five artificially selected GmPIN genes were identified by comparing the genome sequence of 17 wild and 14 cultivated soybean varieties. Our research provides useful and comprehensive basic information for understanding GmPIN genes.
A deletion mutation at the ep locus causes low seed coat peroxidase activity in soybean.
Gijzen, M
1997-11-01
The Ep locus severely affects the amount of peroxidase enzyme in soybean seed coats. Plants containing the dominant Ep allele accumulate large amounts of peroxidase in the hourglass cells of the sub-epidermis. Homozygous recessive epep genotypes do not accumulate peroxidase in the hourglass cells and are much reduced in total seed coat peroxidase activity. To isolate the gene encoding the seed coat peroxidase and to determine whether it corresponds to the Ep locus, a cDNA library was constructed from developing seed coats and an abundant 1.3 kb peroxidase transcript was cloned. The corresponding structural gene was also isolated from a genomic library. Sequence analysis shows that the seed coat peroxidase is translated as a 352 amino acid precursor protein of 38 kDa. Processing of a putative 26 amino acid signal sequence results in a mature protein of 326 residues with a calculated mass of 35 kDa and a pl of 4.4. Using probes derived from the cDNA, genomic DNA blot hybridization and polymerase chain reaction analysis detected polymorphisms that distinguished EpEp and epep genotypes. Co-segregation of the polymorphisms in an F2 population from a cross of EpEp and epep plants shows that the Ep locus encodes the seed coat peroxidase protein. Comparison of Ep and ep alleles indicates that the recessive gene lacks 87 bp of sequence encompassing the translation start codon. Analysis by RNA blot hybridization shows that epep plants have drastically reduced amounts of peroxidase transcript compared with EpEp plants. The peroxidase mRNA is abundant in seed coat tissues of EpEp plants during the late stages of seed maturation, and could also be detected in root tissues, but not in the flower, embryo, pod or leaf. The results indicate that the lack of peroxidase accumulation in seed coats of homozygous recessive epep plants is due to a mutation of the structural gene that reduces transcript abundance.
Dikmen, S; Dahl, G E; Cole, J B; Null, D J; Hansen, P J
2017-03-01
Here we report a previously undescribed coat color phenotype in Holstein cattle. Larson Blue Holsteins, located on a dairy in south Florida, exhibit a coloration pattern that is similar to that of black and white or red and white Holsteins except that, instead of being black or red, darker regions of the body vary in color from gray to taupe. The Larson Blue phenotype was readily apparent in young calves. The phenotype is not due to inheritance of known mutations causing coat color variation in cattle, including dominant red, Telstar, silver color dilutor, or Dun color. Three variants with moderate effects on the () gene were identified in 2 Larson blue cows. Despite being lighter in color, there was no difference in daily variation in vaginal temperature between Larson Blue and other Holsteins when recorded during the summer for cows housed in free-stall barns with shade, fans, and sprinklers. Similarly, there was no effect of the Larson Blue phenotype on seasonal variation in milk yield. Therefore, the phenotype confers no advantage in terms of response to heat stress when cattle are housed in facilities with extensive cooling.
Tucker, Matthew R.; Ma, Chao; Phan, Jana; Neumann, Kylie; Shirley, Neil J.; Hahn, Michael G.; Cozzolino, Daniel; Burton, Rachel A.
2017-01-01
Seeds from the myxospermous species Plantago ovata release a polysaccharide-rich mucilage upon contact with water. This seed coat derived mucilage is composed predominantly of heteroxylan (HX) and is utilized as a gluten-free dietary fiber supplement to promote human colorectal health. In this study, a gamma-irradiated P. ovata population was generated and screened using histological stains and Fourier Transform Mid Infrared (FTMIR) spectroscopy to identify putative mutants showing defects in seed coat mucilage HX composition and/or structure. FTMIR analysis of dry seed revealed variation in regions of the IR spectra previously linked to xylan structure in Secale cereale (rye). Subsequent absorbance ratio and PCA multivariate analysis identified 22 putative mutant families with differences in the HX IR fingerprint region. Many of these showed distinct changes in the amount and subtle changes in structure of HX after mucilage extrusion, while 20% of the putative HX mutants identified by FTMIR showed no difference in staining patterns of extruded mucilage compared to wild-type. Transcriptional screening analysis of two putative reduced xylan in mucilage (rxm) mutants, rxm1 and rxm3, revealed that changes in HX levels in rxm1 correlate with reduced transcription of known and novel genes associated with xylan synthesis, possibly indicative of specific co-regulatory units within the xylan biosynthetic pathway. These results confirm that FTMIR is a suitable method for identifying putative mutants with altered mucilage HX composition in P. ovata, and therefore forms a resource to identify novel genes involved in xylan biosynthesis. PMID:28377777
Lehtinen, Julia; Hyvönen, Zanna; Subrizi, Astrid; Bunjes, Heike; Urtti, Arto
2008-10-21
Cationic polymers are efficient gene delivery vectors in in vitro conditions, but these carriers can fail in vivo due to interactions with extracellular polyanions, i.e. glycosaminoglycans (GAG). The aim of this study was to develop a stable gene delivery vector that is activated at the acidic endosomal pH. Cationic DNA/PEI complexes were coated by 1,2-dioleylphosphatidylethanolamine (DOPE) and cholesteryl hemisuccinate (CHEMS) (3:2 mol/mol) using two coating methods: detergent removal and mixing with liposomes prepared by ethanol injection. Only detergent removal produced lipid-coated DNA complexes that were stable against GAGs, but were membrane active at low pH towards endosome mimicking liposomes. In relation to the low cellular uptake of the coated complexes, their transfection efficacy was relatively high. PEGylation of the coated complexes increased their cellular uptake but reduced the pH-sensitivity. Detergent removal was thus a superior method for the production of stable, but acid activatable, lipid-coated DNA complexes.
Predicted and measured transmission and diffraction by a metallic mesh coating
NASA Astrophysics Data System (ADS)
Halman, Jennifer I.; Ramsey, Keith A.; Thomas, Michael; Griffin, Andrew
2009-05-01
Metallic mesh coatings are used on visible and infrared windows and domes to provide shielding from electromagnetic interference (EMI) and as heaters to de-fog or de-ice windows or domes. The periodic metallic mesh structures that provide the EMI shielding and/or resistive electrical paths for the heating elements create a diffraction pattern when optical or infrared beams are incident on the coated windows. Over the years several different mesh geometries have been used to try to reduce the effects of diffraction. We have fabricated several different mesh patterns on small coupons of BK-7 and measured the transmitted power and the diffraction patterns of each one using a CW 1064 nm laser. In this paper we will present some predictions and measurements of the diffraction patterns of several different mesh patterns.
Twisting integrin receptors increases endothelin-1 gene expression in endothelial cells
NASA Technical Reports Server (NTRS)
Chen, J.; Fabry, B.; Schiffrin, E. L.; Wang, N.; Ingber, D. E. (Principal Investigator)
2001-01-01
A magnetic twisting stimulator was developed based on the previously published technique of magnetic twisting cytometry. Using ligand-coated ferromagnetic microbeads, this device can apply mechanical stresses with varying amplitudes, duration, frequencies, and waveforms to specific cell surface receptors. Biochemical and biological responses of the cells to the mechanical stimulation can be assayed. Twisting integrin receptors with RGD (Arg-Gly-Asp)-containing peptide-coated beads increased endothelin-1 (ET-1) gene expression by >100%. In contrast, twisting scavenger receptors with acetylated low-density lipoprotein-coated beads or twisting HLA antigen with anti-HLA antibody-coated beads did not lead to alterations in ET-1 gene expression. In situ hybridization showed that the increase in ET-1 mRNA was localized in the cells that were stressed with the RGD-coated beads. Blocking stretch-activated ion channels with gadolinium, chelating Ca2+ with EGTA, or inhibiting tyrosine phosphorylation with genistein abolished twist-induced ET-1 mRNA elevation. Abolishing cytoskeletal tension with an inhibitor of the myosin ATPase, with an inhibitor of myosin light chain kinase, or with an actin microfilament disrupter blocked twisted-induced increases in ET-1 expression. Our results are consistent with the hypothesis that the molecular structural linkage of integrin-cytoskeleton is an important pathway for stress-induced ET-1 gene expression.
Grating-patterned FeCo coated surface acoustic wave device for sensing magnetic field
NASA Astrophysics Data System (ADS)
Wang, Wen; Jia, Yana; Xue, Xufeng; Liang, Yong; Du, Zhaofu
2018-01-01
This study addresses the theoretical and experimental investigations of grating-patterned magnetostrictive FeCo coated surface acoustic wave (SAW) device for sensing magnetic field. The proposed sensor is composed of a configuration of differential dual-delay-line oscillators, and a magnetostrictive FeCo grating array deposited along the SAW propagation path of the sensing device, which suppresses effectively the hysteresis effect by releasing the internal binding force in FeCo. The magnetostrictive strain and ΔE effect from the FeCo coating modulates the SAW propagation characteristic, and the corresponding shift in differential oscillation frequency was utilized to evaluate the measurant. A theoretical model is performed to investigate the wave propagation in layered structure of FeCo/LiNbO3 in the effect of magnetostrictive, and allowing determining the optimal structure. The experimental results indicate that higher sensitivity, excellent linearity, and lower hysteresis error over the typical FeCo thin-film coated sensor were achieved from the grating-patterned FeCo coated sensor successfully.
Round-patterned ZnO nanostructure coated with siloxane-based polymer for nerve agent detection
NASA Astrophysics Data System (ADS)
Choi, Hyun Ji; Lee, Ji Won; Jeong, Dong-Cheol; Ha, Seonggyun; Song, Changsik; Boo, Jin-Hyo
2018-01-01
The alignment of zinc oxide (ZnO) nanostructures is expected to improve device sensitivities due to large surface areas which can be utilized to capture significant quantities of gas particles. In this study, we investigated patterned ZnO nanorods modified with polystyrene monolayers synthesized directly onto a quartz crystal microbalance (QCM) cell to increase the coating surface area of the sensing material. Also, we designed and synthesized a siloxane-based polymer (S1 polymer) as a sensing material. The patterned ZnO nanorods coated with S1 polymers were fabricated and used for the detection of dimethyl methylphosphonate (DMMP). The resonance frequency of QCM was shifted due to the adsorption and desorption of a compound at the surface of the modified electrodes. We have synthesized an S1 polymer that exhibited high sensitivity to DMMP. The patterned ZnO nanorods coated with the polymer also exhibited improved sensitivity due to an enhanced surface area capable of adsorbing more DMMP vapor.
An Insertion in the RSPO2 Gene Correlates with Improper Coat in the Portuguese Water Dog
Parker, Heidi G.; Chase, Kevin; Cadieu, Edouard; Lark, Karl Gordon
2010-01-01
We recently showed that genes at 3 loci account for the majority of variation in canine fur. Allelic variation at genes controlling length of fur, texture, and curl is responsible for the striking phenotypic variety observed among purebred dogs in the United States today. In this paper, we investigate the phenomenon of “improper coat” (IC) or a coat that is not typical of the breed. IC is occasionally observed among specific breeds, such as the Portuguese Water Dog (PWD), and is characterized by short hair on the head, face, and lower legs, rather than a thick and even coat covering the whole body. The IC is reminiscent of that observed on the curly or flat-coated retriever, thus making such dogs unable to compete effectively in conformation events. We have found that the presence of the wild-type allele, rather than the expected variant allele at the R-spondin 2 (RSPO2) gene, accounts for this phenotype. The development of a genetic test that distinguishes these 2 allelic types would allow breeders to easily avoid producing PWD with ICs. PMID:20562213
Klaassen, V A; Boeshore, M; Dolja, V V; Falk, B W
1994-07-01
Purified virions of lettuce infectious yellows virus (LIYV), a tentative member of the closterovirus group, contained two RNAs of approximately 8500 and 7300 nucleotides (RNAs 1 and 2 respectively) and a single coat protein species with M(r) of approximately 28,000. LIYV-infected plants contained multiple dsRNAs. The two largest were the correct size for the replicative forms of LIYV virion RNAs 1 and 2. To assess the relationships between LIYV RNAs 1 and 2, cDNAs corresponding to the virion RNAs were cloned. Northern blot hybridization analysis showed no detectable sequence homology between these RNAs. A partial amino acid sequence obtained from purified LIYV coat protein was found to align in the most upstream of four complete open reading frames (ORFs) identified in a LIYV RNA 2 cDNA clone. The identity of this ORF was confirmed as the LIYV coat protein gene by immunological analysis of the gene product expressed in vitro and in Escherichia coli. Computer analysis of the LIYV coat protein amino acid sequence indicated that it belongs to a large family of proteins forming filamentous capsids of RNA plant viruses. The LIYV coat protein appears to be most closely related to the coat proteins of two closteroviruses, beet yellows virus and citrus tristeza virus.
Positive selection on human gamete-recognition genes
Stover, Daryn A.; Guerra, Vanessa; Mozaffari, Sahar V.; Ober, Carole; Mugal, Carina F.; Kaj, Ingemar
2018-01-01
Coevolution of genes that encode interacting proteins expressed on the surfaces of sperm and eggs can lead to variation in reproductive compatibility between mates and reproductive isolation between members of different species. Previous studies in mice and other mammals have focused in particular on evidence for positive or diversifying selection that shapes the evolution of genes that encode sperm-binding proteins expressed in the egg coat or zona pellucida (ZP). By fitting phylogenetic models of codon evolution to data from the 1000 Genomes Project, we identified candidate sites evolving under diversifying selection in the human genes ZP3 and ZP2. We also identified one candidate site under positive selection in C4BPA, which encodes a repetitive protein similar to the mouse protein ZP3R that is expressed in the sperm head and binds to the ZP at fertilization. Results from several additional analyses that applied population genetic models to the same data were consistent with the hypothesis of selection on those candidate sites leading to coevolution of sperm- and egg-expressed genes. By contrast, we found no candidate sites under selection in a fourth gene (ZP1) that encodes an egg coat structural protein not directly involved in sperm binding. Finally, we found that two of the candidate sites (in C4BPA and ZP2) were correlated with variation in family size and birth rate among Hutterite couples, and those two candidate sites were also in linkage disequilibrium in the same Hutterite study population. All of these lines of evidence are consistent with predictions from a previously proposed hypothesis of balancing selection on epistatic interactions between C4BPA and ZP3 at fertilization that lead to the evolution of co-adapted allele pairs. Such patterns also suggest specific molecular traits that may be associated with both natural reproductive variation and clinical infertility. PMID:29340252
Tekleyohans, Dawit G.; Wittkop, Benjamin; Snowdon, Rod J.
2016-01-01
Seed formation is a pivotal process in plant reproduction and dispersal. It begins with megagametophyte development in the ovule, followed by fertilization and subsequently coordinated development of embryo, endosperm, and maternal seed coat. Two closely related MADS-box genes, SHATTERPROOF 1 and 2 (SHP1 and SHP2) are involved in specifying ovule integument identity in Arabidopsis thaliana. The MADS box gene ARABIDOPSIS BSISTER (ABS or TT16) is required, together with SEEDSTICK (STK) for the formation of endothelium, part of the seed coat and innermost tissue layer formed by the maternal plant. Little is known about the genetic interaction of SHP1 and SHP2 with ABS and the coordination of endosperm and seed coat development. In this work, mutant and expression analysis shed light on this aspect of concerted development. Triple tt16 shp1 shp2 mutants produce malformed seedlings, seed coat formation defects, fewer seeds, and mucilage reduction. While shp1 shp2 mutants fail to coordinate the timely development of ovules, tt16 mutants show less peripheral endosperm after fertilization. Failure in coordinated division of the innermost integument layer in early ovule stages leads to inner seed coat defects in tt16 and tt16 shp1 shp2 triple mutant seeds. An antagonistic action of ABS and SHP1/SHP2 is observed in inner seed coat layer formation. Expression analysis also indicates that ABS represses SHP1, SHP2, and FRUITFUL expression. Our work shows that the evolutionary conserved Bsister genes are required not only for endothelium but also for endosperm development and genetically interact with SHP1 and SHP2 in a partially antagonistic manner. PMID:27776173
Biodegradable DNA Nanoparticles that Provide Widespread Gene Delivery in the Brain
Mastorakos, Panagiotis; Song, Eric; Zhang, Clark; Berry, Sneha; Park, Hee Won; Kim, Young Eun; Park, Jong Sung; Lee, Seulki; Suk, Jung Soo; Hanes, Justin
2016-01-01
Successful gene therapy of neurological disorders is predicated on achieving widespread and uniform transgene expression throughout the affected disease area in the brain. However, conventional gene vectors preferentially travel through low-resistance perivascular spaces and/or are confined to the administration site even with the aid of a pressure-driven flow provided by convection-enhanced delivery. Biodegradable DNA nanoparticles offer a safe gene delivery platform devoid of adverse effects associated with virus-based or synthetic non-biodegradable systems. Using a state-of-the-art biodegradable polymer, poly(β-amino ester), we engineered colloidally stable sub-100 nm DNA nanoparticles coated with a non-adhesive polyethylene glycol corona that are able to avoid the adhesive and steric hindrances imposed by the extracellular matrix. Following convection enhanced delivery, these brain-penetrating nanoparticles were able to homogeneously distribute throughout the rodent striatum and mediate widespread and high-level transgene expression. These nanoparticles provide a biodegradable DNA nanoparticle platform enabling uniform transgene expression patterns in vivo and hold promise for the treatment of neurological diseases. PMID:26680637
Gorzkiewicz, Michał; Sztandera, Krzysztof; Jatczak-Pawlik, Izabela; Zinke, Robin; Appelhans, Dietmar; Klajnert-Maculewicz, Barbara; Pulaski, Łukasz
2018-05-14
Poly(propyleneimine) dendrimers fully surface-modified with disaccharide moieties (maltose, cellobiose, and lactose) designed to mimic natural lectin receptor ligands were tested for their bioactivity in two myeloid cell lines: THP-1 and HL-60. Depending on the sugar modification, we observed variable activation of NF-κB, AP-1, and NF-AT signaling pathways: lactose-coated dendrimers had the strongest impact on marker gene expression and most signaling events with the notable exception of NF-κB activation in THP-1 cells. The two cell lines showed an overall similar pattern of transcription factor and gene expression activation upon treatment with glycodendrimers, suggesting the involvement of galectin and C-type lectin receptor types. An important result of this action was the overexpression of CD40 and IL8 genes, potentially leading to an activated, proinflammatory phenotype in the monocyte/macrophage cell lineage. These pharmacodynamic characteristics of glycodendrimers need to be taken into account during their pharmaceutical applications both in drug delivery and direct immunomodulation.
MC1R studies in dogs with melanistic mask or brindle patterns.
Schmutz, S M; Berryere, T G; Ellinwood, N M; Kerns, J A; Barsh, G S
2003-01-01
Black mask is a characteristic pattern in which red, yellow, tan, fawn, or brindle dogs exhibit a melanistic muzzle which may extend up onto the ears. Melanistic mask is inherited in several breeds as an autosomal dominant trait, and appears to be a fixed trait in a few breeds of dogs. A MC1R nonsense mutation, R306ter, has been shown to cause a completely red or yellow coat color in certain breeds such as Irish setters, yellow Labrador retrievers, and golden retrievers. The amino acid sequence for the melanocortin receptor 1 gene (MC1R) was examined in 17 dogs with melanistic masks from seven breeds, 19 dogs without melanistic masks, and 7 dogs in which their coat color made the mask difficult to distinguish. We also examined nine brindle dogs of four breeds, including three dogs who also had a black mask. No consistent amino acid change was observed in the brindle dogs. All dogs with a melanistic mask had at least one copy of a valine substitution for methionine at amino acid 264 (M264V) and none were homozygous for the premature stop codon (R306ter). These results suggest that black mask, but not brindle, is caused by a specific MC1R allele.
Development of Charge Drain Coatings: Final CRADA Report
DOE Office of Scientific and Technical Information (OSTI.GOV)
Elam, Jeffrey W.
2017-01-17
The primary goal of this CRADA project was to develop and optimize tunable resistive coatings prepared by atomic layer deposition (ALD) for use as charge-drain coatings on the KLA-Tencor digital pattern generators (DPGs).
Printing-assisted surface modifications of patterned ultrafiltration membranes
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wardrip, Nathaniel C.; Dsouza, Melissa; Urgun-Demirtas, Meltem
Understanding and restricting microbial surface attachment will enhance wastewater treatment with membranes. We report a maskless lithographic patterning technique for the generation of patterned polymer coatings on ultrafiltration membranes. Polyethylene glycol, zwitterionic, or negatively charged hydrophilic polymer compositions in parallel- or perpendicular-striped patterns with respect to feed flow were evaluated using wastewater. Membrane fouling was dependent on the orientation and chemical composition of the coatings. Modifications reduced alpha diversity in the attached microbial community (Shannon indices decreased from 2.63 to 1.89) which nevertheless increased with filtration time. Sphingomonas species, which condition membrane surfaces and facilitate cellular adhesion, were depleted inmore » all modified membranes. Microbial community structure was significantly different between control, different patterns, and different chemistries. Lastly, this study broadens the tools for surface modification of membranes with polymer coatings and for understanding and optimization of antifouling surfaces.« less
Printing-assisted surface modifications of patterned ultrafiltration membranes
Wardrip, Nathaniel C.; Dsouza, Melissa; Urgun-Demirtas, Meltem; ...
2016-10-17
Understanding and restricting microbial surface attachment will enhance wastewater treatment with membranes. We report a maskless lithographic patterning technique for the generation of patterned polymer coatings on ultrafiltration membranes. Polyethylene glycol, zwitterionic, or negatively charged hydrophilic polymer compositions in parallel- or perpendicular-striped patterns with respect to feed flow were evaluated using wastewater. Membrane fouling was dependent on the orientation and chemical composition of the coatings. Modifications reduced alpha diversity in the attached microbial community (Shannon indices decreased from 2.63 to 1.89) which nevertheless increased with filtration time. Sphingomonas species, which condition membrane surfaces and facilitate cellular adhesion, were depleted inmore » all modified membranes. Microbial community structure was significantly different between control, different patterns, and different chemistries. Lastly, this study broadens the tools for surface modification of membranes with polymer coatings and for understanding and optimization of antifouling surfaces.« less
Zhao, Xinxin; Irvine, Scott Alexander; Agrawal, Animesh; Cao, Ye; Lim, Pei Qi; Tan, Si Ying; Venkatraman, Subbu S
2015-10-01
The optimal bio-artificial blood vessel construct is one that has a compliant tubular core with circumferentially aligned smooth muscle cells (SMCs). Obtaining this well-aligned pattern of SMCs on a scaffold is highly beneficial as this cellular orientation preserves the SMC contractile phenotype. We used 3D patterning to create channels on a polycaprolactone (PCL) scaffold; SMCs were then found to be aligned within the microchannels. To preserve this alignment, and to provide a protective coating that could further incorporate cells, we evaluated the use of two hydrogels, one based on poly(ethylene glycol) diacrylate (PEGDA) and the other based on gelatin. Hydrogels were either physically coated on the PCL surfaces or covalently linked via suitable surface modification of PCL. For covalent immobilization of PEGDA hydrogel, alkene groups were introduced on PCL, while for gelatin covalent linkage, serum proteins were introduced. It is, however, crucial that the hydrogel coating does not disrupt the cellular patterning and distribution. We show in this work that both the process of coating as well as the nature of the coating are critical to preservation of the aligned SMCs. The covalent coating methods involving the crosslinking of hydrogels with the surface of PCL films promoted hydrogel retention time on the film as compared with physical deposition. Furthermore, subsequent hydrogel degradation is affected by the components of the cell culture medium, hinting at a possible route to in vivo biodegradation. Surface features control cellular orientation and subsequently influence their functionality, a useful effect for cellularized biomedical devices. Such devices also can benefit from protective and cell friendly hydrogel coatings. However, literature is lacking on the fate of cells that have endured hydrogel coating whilst orientated on a biomaterial surface. In particular, elucidation of the cells ability to remain adherent and orientated post hydrogel addition. Coating requires two procedures that may be deleterious to the orientated cells: the surface pretreatment for gel binding and the hydrogel crosslinking reaction. We compare transglutaminase gelatin crosslinking and UV initiated PEGDA crosslinking, coated onto smooth muscle cells orientated on patterned PCL surfaces. This original study will be of considerable use to the wider biomaterials community. Copyright © 2015 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.
Gene delivery to skin using biolistics.
Heiser, William C
2006-06-01
INTRODUCTION Biolistics ("biological ballistics") or particle bombardment provides a rapid and simple physical procedure for delivering genes into cells (Klein et al. 1987; Yang et al. 1990). The technique has many advantages-plasmids may be used for delivery, DNA theoretically can be delivered to any cell type, and genes may be delivered to cells in vitro, ex vivo, or in vivo. DNA-coated gold particles are distributed evenly along the length of the tubing, which is subsequently cut into short sections of cartridges to be used in a gene gun. The Helios Gene Gun uses a pulse of helium to launch the DNA-coated particles, spreading them onto the target cells.
Ehashi, Tomo; Takemura, Taro; Hanagata, Nobutaka; Minowa, Takashi; Kobayashi, Hisatoshi; Ishihara, Kazuhiko; Yamaoka, Tetsuji
2014-01-01
To design scaffolds for tissue regeneration, details of the host body reaction to the scaffolds must be studied. Host body reactions have been investigated mainly by immunohistological observations for a long time. Despite of recent dramatic development in genetic analysis technologies, genetically comprehensive changes in host body reactions are hardly studied. There is no information about host body reactions that can predict successful tissue regeneration in the future. In the present study, porous polyethylene scaffolds were coated with bioactive collagen or bio-inert poly(2-methacryloyloxyethyl phosphorylcholine-co-n-butyl methacrylate) (PMB) and were implanted subcutaneously and compared the host body reaction to those substrates by normalizing the result using control non-coat polyethylene scaffold. The comprehensive analyses of early host body reactions to the scaffolds were carried out using a DNA microarray assay. Within numerous genes which were expressed differently among these scaffolds, particular genes related to inflammation, wound healing, and angiogenesis were focused upon. Interleukin (IL)-1β and IL-10 are important cytokines in tissue responses to biomaterials because IL-1β promotes both inflammation and wound healing and IL-10 suppresses both of them. IL-1β was up-regulated in the collagen-coated scaffold. Collagen-specifically up-regulated genes contained both M1- and M2-macrophage-related genes. Marked vessel formation in the collagen-coated scaffold was occurred in accordance with the up-regulation of many angiogenesis-inducible factors. The DNA microarray assay provided global information regarding the host body reaction. Interestingly, several up-regulated genes were detected even on the very bio-inert PMB-coated surfaces and those genes include inflammation-suppressive and wound healing-suppressive IL-10, suggesting that not only active tissue response but also the inert response may relates to these genetic regulations. PMID:24454803
Miron, Richard J; Bosshardt, Dieter D; Laugisch, Oliver; Dard, Michel; Gemperli, Anja C; Buser, Daniel; Gruber, Reinhard; Sculean, Anton
2013-11-01
Preclinical and clinical studies suggest that a combination of enamel matrix derivative (EMD) with demineralized freeze-dried bone allograft (DFDBA) may improve periodontal wound healing and regeneration. To date, no single study has characterized the effects of this combination on in vitro cell behavior. The aim of this study is to test the ability of EMD to adsorb to the surface of DFDBA particles and determine the effect of EMD coating on downstream cellular pathways such as adhesion, proliferation, and differentiation of primary human osteoblasts and periodontal ligament (PDL) cells. DFDBA particles were precoated with EMD or human blood and analyzed for protein adsorption patterns via scanning electron microscopy. Cell attachment and proliferation were quantified using a commercial assay. Cell differentiation was analyzed using real-time polymerase chain reaction for genes encoding Runx2, alkaline phosphatase, osteocalcin, and collagen 1α1, and mineralization was assessed using alizarinred staining. Analysis of cell attachment revealed no significant differences among control, blood-coated, and EMD-coated DFDBA particles. EMD significantly increased cell proliferation at 3 and 5 days after seeding for both osteoblasts and PDL cells compared to control and blood-coated samples. Moreover, there were significantly higher messenger ribonucleic acid levels of osteogenic differentiation markers, including collagen 1α1, alkaline phosphatase, and osteocalcin, in osteoblasts and PDL cells cultured on EMD-coated DFDBA particles at 3, 7, and 14 days. The results suggest that the addition of EMD to DFDBA particles may influence periodontal regeneration by stimulating PDL cell and osteoblast proliferation and differentiation.
Dempsey, Christopher; Lee, Isac; Cowan, Katie; Suh, Junghae
2015-01-01
Barium titanate nanoparticles (BT NP) belong to a class of second harmonic generating (SHG) nanoprobes that have recently demonstrated promise in biological imaging. Unfortunately, BT NPs display low cellular uptake efficiencies, which may be a problem if cellular internalization is desired or required for a particular application. To overcome this issue, while concomitantly developing a particle platform that can also deliver nucleic acids into cells, we coated the BT NPs with the cationic polymer polyethylenimine (PEI) – one of the most effective nonviral gene delivery agents. Coating of BT with PEI yielded complexes with positive zeta potentials and resulted in an 8-fold increase in cellular uptake of the BT NPs. Importantly, we were able to achieve high levels of gene delivery with the BT-PEI/DNA complexes, supporting further efforts to generate BT platforms for coupled imaging and gene therapy. PMID:23973999
Uchiyama, Hiroaki; Mantani, Yuto; Kozuka, Hiromitsu
2012-07-10
Complex, sophisticated surface patterns on micrometer and nanometer scales are obtained when solvent evaporates from solutions containing nonvolatile solutes dropped on a solid substrate. Such evaporation-driven pattern formation has been utilized as a fabrication process of highly ordered patterns in thin films. Here, we suggested the spontaneous pattern formation induced by Bénard-Marangoni convection triggered by solvent evaporation as a novel patterning process of sol-gel-derived organic-inorganic hybrid films. Microcraters of 1.0-1.5 μm in height and of 100-200 μm in width were spontaneously formed on the surface of silica-poly(vinylpyrrolidone) hybrid films prepared via temperature-controlled dip-coating process, where the surface patterns were linearly arranged parallel to the substrate withdrawal direction. Such highly ordered micropatterns were achieved by Bénard-Marangoni convection activated at high temperatures and the unidirectional flow of the coating solution on the substrate during dip-coating.
On the origin and removal of interference patterns in coated multimode fibres
NASA Astrophysics Data System (ADS)
Padilla Michel, Yazmin; Pulwer, Silvio; Saffari, Pouneh; Ksianzou, Viachaslau; Schrader, Sigurd
2016-07-01
In this study, we present the experimental investigations on interference patterns, such as those already reported in VIMOS-IFU, and up to now no appropriate explanation has been presented. These interference patterns are produced in multimode fibres coated with acrylate or polyimide, which is the preferred coating material for the fibres used in IFUs. Our experiments show that, under specific conditions, cladding modes interact with the coating and produce interference. Our results show that the conditions at which the fibre is held during data acquisition has an impact in the output spectrum. Altering the positioning conditions of the fibre leads to the changes into the interference pattern, therefore, fibres should be carefully manipulated in order to minimise this potential problem and improve the performance of these instruments. Finally we present a simple way of predicting and modelling this interference produced from the visible to the near infrared spectra. This model can be included in the data reduction pipeline in order to remove the interference patterns. These results should be of interest for the optimisation of the data reduction pipelines of instruments using optical fibres. Considering these results will benefit innovations and developments of high performance fibre systems.
Fontanesi, Luca; Scotti, Emilio; Colombo, Michela; Beretti, Francesca; Forestier, Lionel; Dall'Olio, Stefania; Deretz, Séverine; Russo, Vincenzo; Allain, Daniel; Oulmouden, Ahmad
2010-07-01
In the domestic rabbit (Oryctolagus cuniculus), classical genetic studies have identified five alleles at the Extension locus: ED (dominant black), ES (steel, weaker version of ED), E (wild type, normal extension of black), eJ(Japanese brindling, mosaic distribution of black and yellow) and e (non-extension of black, yellow/red with white belly). Sequencing almost the complete coding sequence (CDS) of the rabbit MC1R gene, we recently identified two in-frame deletions associated with dominant black (c.280_285del6; alleles ED or ES) and recessive red (c.304_333del30; allele e) coat colours. It remained to characterize the eJallele whose phenotypic effect is similar to the Orange and Sex-linked yellow loci of cat and Syrian hamster. We sequenced the whole CDS in 25 rabbits of different coat colours including 10 Japanese and 10 Rhinelander (tricolour) rabbits and identified another 6 bp-in frame deletion flanked by a G > A transition in 5' (c.[124G>A;125_130del6]) that was present in all animals with Japanese brindling coat colour and pattern. These mutations eliminate two amino acids in the first transmembrane domain and, in addition, cause an amino acid substitution at position 44 of the wild type sequence. Genotyping 371 rabbits of 31 breeds with different coat colour this allele (eJ) was present in homozygous state in Japanese, Rhinelander and Dutch tricolour rabbits only (except one albino rabbit). Rabbits with eJ/eJ genotype were non fixed at the non-agouti mutation we previously identified in the ASIP gene. Segregation in F1 and F2 families confirmed the order of dominance already determined by classical genetic experiments with a possible dose effect evident comparing eJ/eJ and eJ/e animals. MC1R mRNA was expressed in black hair skin regions only. The c.[124A;125_130del6] allele may be responsible for a MC1R variant determining eumelanin production in the black areas. However, the mechanism determining the presence of both red and black hairs in the same animal seems more complex. Expression analyses of the c.[124A;125_130del6] allele suggest that MC1R transcription may be regulated epigenetically in rabbits with the Japanese brindling phenotype. Further studies are needed to clarify this issue.
Sridharan, BanuPriya; Laflin, Amy D; Detamore, Michael S
2018-04-01
Spheroids of mesenchymal stem cells (MSCs) in cartilage tissue engineering have been shown to enhance regenerative potential owing to their 3D structure. In this study, we explored the possibility of priming spheroids under different media to replace the use of inductive surface coatings for chondrogenic differentiation. Rat bone marrow-derived MSCs were organized into cell spheroids by the hanging drop technique and subsequently cultured on hyaluronic acid (HA) coated or non-coated well plates under different cell media conditions. Endpoint analysis included cell viability, DNA and Glycosaminoglycan (GAG) and collagen content, gene expression and immunohistochemistry. For chondrogenic applications, MSC spheroids derived on non-coated surfaces outperformed the spheroids derived from HA-coated surfaces in matrix synthesis and collagen II gene expression. Spheroids on non-coated surfaces gave rise to the highest collagen and GAG when primed with medium containing insulin-like growth factor (IGF) for 1 week during spheroid formation. Spheroids that were grown in chondroinductive raw material-inclusive media such as aggrecan or chondroitin sulfate exhibited the highest Collagen II gene expression in the non-coated surface at 1 week. Media priming by growth factors and raw materials might be a more predictive influencer of chondrogenesis compared to inductive-surfaces. Such tailored bioactivity of the stem cell spheroids in the stage of the spheroid formation may give rise to a platform technology that may eventually produce spheroids capable of chondrogenesis achieved by mere media manipulation, skipping the need for additional culture on a modified surface, that paves the way for cost-effective technologies.
Umasankar, Perunthottathu K; Ma, Li; Thieman, James R; Jha, Anupma; Doray, Balraj; Watkins, Simon C; Traub, Linton M
2014-01-01
Clathrin-mediated endocytosis is an evolutionarily ancient membrane transport system regulating cellular receptivity and responsiveness. Plasmalemma clathrin-coated structures range from unitary domed assemblies to expansive planar constructions with internal or flanking invaginated buds. Precisely how these morphologically-distinct coats are formed, and whether all are functionally equivalent for selective cargo internalization is still disputed. We have disrupted the genes encoding a set of early arriving clathrin-coat constituents, FCHO1 and FCHO2, in HeLa cells. Endocytic coats do not disappear in this genetic background; rather clustered planar lattices predominate and endocytosis slows, but does not cease. The central linker of FCHO proteins acts as an allosteric regulator of the prime endocytic adaptor, AP-2. By loading AP-2 onto the plasma membrane, FCHO proteins provide a parallel pathway for AP-2 activation and clathrin-coat fabrication. Further, the steady-state morphology of clathrin-coated structures appears to be a manifestation of the availability of the muniscin linker during lattice polymerization. DOI: http://dx.doi.org/10.7554/eLife.04137.001 PMID:25303365
Nanosecond multi-pulse laser milling for certain area removal of metal coating on plastics surface
NASA Astrophysics Data System (ADS)
Zhao, Kai; Jia, Zhenyuan; Ma, Jianwei; Liu, Wei; Wang, Ling
2014-12-01
Metal coating with functional pattern on engineering plastics surface plays an important role in industry applications; it can be obtained by adding or removing certain area of metal coating on engineering plastics surface. However, the manufacturing requirements are improved continuously and the plastic substrate presents three-dimensional (3D) structure-many of these parts cannot be fabricated by conventional processing methods, and a new manufacturing method is urgently needed. As the laser-processing technology has many advantages like high machining accuracy and constraints free substrate structure, the machining of the parts is studied through removing certain area of metal coating based on the nanosecond multi-pulse laser milling. To improve the edge quality of the functional pattern, generation mechanism and corresponding avoidance strategy of the processing defects are studied. Additionally, a prediction model for the laser ablation depth is proposed, which can effectively avoid the existence of residual metal coating and reduces the damage of substrate. With the optimal machining parameters, an equiangular spiral pattern on copper-clad polyimide (CCPI) is machined based on the laser milling at last. The experimental results indicate that the edge of the pattern is smooth and consistent, the substrate is flat and without damage. The achievements in this study could be applied in industrial production.
Prototyping Of Patterned Functional Nanostructures
Fan, Hongyou; Lopez, Gabriel P.; Brinker, Charles Jeffrey; Lu, Yunfeng
2002-10-29
The present invention provides a coating composition comprising: A coating composition comprising: TEOS; a surfactant; at least one organosilane; HCl; water; and ethanol. The present invention also provides films made from such a coating composition and a method for making such films.
[The genetic control of mouse coat color and its applications in genetics teaching].
Xing, Wanjin; Morigen, Morigen
2014-10-01
Mice are the most commonly used mammalian model. The coat colors of mice are typical Mendelian traits, which have various colors such as white, black, yellow and agouti. The inheritance of mouse coat color is usually stated as an example only in teaching the knowledge of recessive lethal alleles. After searched the related literatures and summarized the molecular mechanisms of mouse coat color inheritance, we further expanded the application of this example into the introduction of the basic concepts of alleles and Mendelian laws, demonstration of the gene structure and function, regulation of gene expression, gene interaction, epigenetic modification, quantitative genetics, as well as evolutionary genetics. By running this example through the whole genetics-teaching lectures, we help the student to form a systemic and developmental view of genetic analysis. At the same time, this teaching approach not only highlights the advancement and integrity of genetics, but also results in a good teaching effect on inspiring the students' interest and attracting students' attention.
Renouard, Sullivan; Corbin, Cyrielle; Lopez, Tatiana; Montguillon, Josiane; Gutierrez, Laurent; Lamblin, Frédéric; Lainé, Eric; Hano, Christophe
2012-01-01
Secoisolariciresinol diglucoside (SDG), the main phytoestrogenic lignan of Linum usitatissimum, is accumulated in the seed coat of flax during its development and pinoresinol-lariciresinol reductase (PLR) is a key enzyme in flax for its synthesis. The promoter of LuPLR1, a flax gene encoding a pinoresinol lariciresinol reductase, contains putative regulatory boxes related to transcription activation by abscisic acid (ABA). Gel mobility shift experiments evidenced an interaction of nuclear proteins extracted from immature flax seed coat with a putative cis-acting element involved in ABA response. As ABA regulates a number of physiological events during seed development and maturation we have investigated its involvement in the regulation of this lignan synthesis by different means. ABA and SDG accumulation time courses in the seed as well as LuPLR1 expression were first determined in natural conditions. These results showed that ABA timing and localization of accumulation in the flax seed coat could be correlated with the LuPLR1 gene expression and SDG biosynthesis. Experimental modulations of ABA levels were performed by exogenous application of ABA or fluridone, an inhibitor of ABA synthesis. When submitted to exogenous ABA, immature seeds synthesized 3-times more SDG, whereas synthesis of SDG was reduced in immature seeds treated with fluridone. Similarly, the expression of LuPLR1 gene in the seed coat was up-regulated by exogenous ABA and down-regulated when fluridone was applied. These results demonstrate that SDG biosynthesis in the flax seed coat is positively controlled by ABA through the transcriptional regulation of LuPLR1 gene.
Thiokol 260-SL Nozzle Development Program
1967-01-01
Pigure 1 Candidate Throat Inserts ............................ 7 2 Laminate Temperature versus Coating Thickness for Selectron 5003 Specimens...32 Photo Cross Adhesive Pattern ....................... 111 33 Photo Parallel Adhesive Pattern ..................... 112 34 Adhesive Applicator Teeth ...Ablative Material .... 88 XXXIII Task 9: Corlar Coating of Graphite Materials Throat, IS 11004-01-02, 156-ZC-1 ............ ....... 90 XXXIV Adapter
Dong, Changsheng; Wang, Haidong; Xue, Linli; Dong, Yanjun; Yang, Lei; Fan, Ruiwen; Yu, Xiuju; Tian, Xue; Ma, Shuhui; Smith, George W.
2012-01-01
Coat color is a key economic trait in wool-producing species. Color development and pigmentation are controlled by complex mechanisms in animals. Here, we report the first production of an altered coat color by overexpression of miR-137 in transgenic mice. Transgenic mice overexpressing miR-137 developed a range of coat color changes from dark black to light color. Molecular analyses of the transgenic mice showed decreased expression of the major target gene termed MITF and its downstream genes, including TYR, TYRP1, and TYRP2. We also showed that melanogenesis altered by miR-137 is distinct from that affected by UV radiation in transgenic mice. Our study provides the first mouse model for the study of coat color controlled by miRNAs in animals and may have important applications in wool production. PMID:22847819
The genetics of brown coat color and white spotting in domestic yaks (Bos grunniens).
Zhang, M-Q; Xu, X; Luo, S-J
2014-10-01
Domestic yaks (Bos grunniens) exhibit two major coat color variations: a brown vs. wild-type black pigmentation and a white spotting vs. wild-type solid color pattern. The genetic basis for these variations in color and distribution remains largely unknown and may be complicated by a breeding history involving hybridization between yaks and cattle. Here, we investigated 92 domestic yaks from China using a candidate gene approach. Sequence variations in MC1R, PMEL and TYRP1 were surveyed in brown yaks; TYRP1 was unassociated with the coloration and excluded. Recessive mutations from MC1R, or p.Gln34*, p.Met73Leu and possibly p.Arg142Pro, are reported in bovids for the first time and accounted for approximately 40% of the brown yaks in this study. The remaining 60% of brown individuals correlated with a cattle-derived deletion mutation from PMEL (p.Leu18del) in a dominant manner. Degrees of white spotting found in yaks vary from color sidedness and white face, to completely white. After examining the candidate gene KIT, we suggest that color-sided and all-white yaks are caused by the serial translations of KIT (Cs6 or Cs29 ) as reported for cattle. The white-faced phenotype in yaks is associated with the KIT haplotype S(wf) . All KIT mutations underlying the serial phenotypes of white spotting in yaks are identical to those in cattle, indicating that cattle are the likely source of white spotting in yaks. Our results reveal the complex genetic origins of domestic yak coat color as either native in yaks through evolution and domestication or as introduced from cattle through interspecific hybridization. © 2014 Stichting International Foundation for Animal Genetics.
NASA Astrophysics Data System (ADS)
Schutzius, Thomas M.; Bayer, Ilker S.; Jursich, Gregory M.; Das, Arindam; Megaridis, Constantine M.
2012-08-01
Surfaces patterned with alternating (binary) superhydrophobic-superhydrophilic regions can be found naturally, offering a bio-inspired template for efficient fluid collection and management technologies. We describe a simple wet-processing, thermal treatment method to produce such patterns, starting with inherently superhydrophobic polysilsesquioxane-silica composite coatings prepared by spray casting nanoparticle dispersions. Such coatings become superhydrophilic after localized thermal treatment by means of laser irradiation or open-air flame exposure. When laser processed, the films are patternable down to ~100 μm scales. The dispersions consist of hydrophobic fumed silica (HFS) and methylsilsesquioxane resin, which are dispersed in isopropanol and deposited onto various substrates (glass, quartz, aluminum, copper, and stainless steel). The coatings are characterized by advancing, receding, and sessile contact angle measurements before and after thermal treatment to delineate the effects of HFS filler concentration and thermal treatment on coating wettability. SEM, XPS and TGA measurements reveal the effects of thermal treatment on surface chemistry and texture. The thermally induced wettability shift from superhydrophobic to superhydrophilic is interpreted with the Cassie-Baxter wetting theory. Several micropatterned wettability surfaces demonstrate potential in pool boiling heat transfer enhancement, capillarity-driven liquid transport in open surface-tension-confined channels (e.g., lab-on-a-chip), and select surface coating applications relying on wettability gradients. Advantages of the present approach include the inherent stability and inertness of the organosilane-based coatings, which can be applied on many types of surfaces (glass, metals, etc.) with ease. The present method is also scalable to large areas, thus being attractive for industrial coating applications.Surfaces patterned with alternating (binary) superhydrophobic-superhydrophilic regions can be found naturally, offering a bio-inspired template for efficient fluid collection and management technologies. We describe a simple wet-processing, thermal treatment method to produce such patterns, starting with inherently superhydrophobic polysilsesquioxane-silica composite coatings prepared by spray casting nanoparticle dispersions. Such coatings become superhydrophilic after localized thermal treatment by means of laser irradiation or open-air flame exposure. When laser processed, the films are patternable down to ~100 μm scales. The dispersions consist of hydrophobic fumed silica (HFS) and methylsilsesquioxane resin, which are dispersed in isopropanol and deposited onto various substrates (glass, quartz, aluminum, copper, and stainless steel). The coatings are characterized by advancing, receding, and sessile contact angle measurements before and after thermal treatment to delineate the effects of HFS filler concentration and thermal treatment on coating wettability. SEM, XPS and TGA measurements reveal the effects of thermal treatment on surface chemistry and texture. The thermally induced wettability shift from superhydrophobic to superhydrophilic is interpreted with the Cassie-Baxter wetting theory. Several micropatterned wettability surfaces demonstrate potential in pool boiling heat transfer enhancement, capillarity-driven liquid transport in open surface-tension-confined channels (e.g., lab-on-a-chip), and select surface coating applications relying on wettability gradients. Advantages of the present approach include the inherent stability and inertness of the organosilane-based coatings, which can be applied on many types of surfaces (glass, metals, etc.) with ease. The present method is also scalable to large areas, thus being attractive for industrial coating applications. Electronic supplementary information (ESI) available. See DOI: 10.1039/c2nr30979c
Takenaka, Chiemi; Miyajima, Hiroshi; Yoda, Yusuke; Imazato, Hideo; Yamamoto, Takako; Gomi, Shinichi; Ohshima, Yasuhiro; Kagawa, Kenichi; Sasaki, Tetsuji; Kawamata, Shin
2015-01-01
Here, we introduce a new serum-free defined medium (SPM) that supports the cultivation of human pluripotent stem cells (hPSCs) on recombinant human vitronectin-N (rhVNT-N)-coated dishes after seeding with either cell clumps or single cells. With this system, there was no need for an intervening sequential adaptation process after moving hPSCs from feeder layer-dependent conditions. We also introduce a micropatterned dish that was coated with extracellular matrix by photolithographic technology. This procedure allowed the cultivation of hPSCs on 199 individual rhVNT-N-coated small round spots (1 mm in diameter) on each 35-mm polystyrene dish (termed “patterned culture”), permitting the simultaneous formation of 199 uniform high-density small-sized colonies. This culture system supported controlled cell growth and maintenance of undifferentiated hPSCs better than dishes in which the entire surface was coated with rhVNT-N (termed “non-patterned cultures”). Non-patterned cultures produced variable, unrestricted cell proliferation with non-uniform cell growth and uneven densities in which we observed downregulated expression of some self-renewal-related markers. Comparative flow cytometric studies of the expression of pluripotency-related molecules SSEA-3 and TRA-1-60 in hPSCs from non-patterned cultures and patterned cultures supported this concept. Patterned cultures of hPSCs allowed sequential visual inspection of every hPSC colony, giving an address and number in patterned culture dishes. Several spots could be sampled for quality control tests of production batches, thereby permitting the monitoring of hPSCs in a single culture dish. Our new patterned culture system utilizing photolithography provides a robust, reproducible and controllable cell culture system and demonstrates technological advantages for the mass production of hPSCs with process quality control. PMID:26115194
Wang, Fulin; He, Jiewang; Shi, Jianghua; Zheng, Tao; Xu, Fei; Wu, Guanting; Liu, Renhu; Liu, Shengyi
2016-01-01
Seed coat color is determined by the type of pigment deposited in the seed coat cells. It is related to important agronomic traits of seeds such as seed dormancy, longevity, oil content, protein content and fiber content. In Brassica napus, inheritance of seed coat color is related to maternal effects and pollen effects (xenia effects). In this research we isolated a mutation of yellow seeded B. napus controlled by a single Mendelian locus, which is named Embryonal Control of Yellow seed coat 1 (Ecy1). Microscopy of transverse sections of the mature seed show that pigment is deposited only in the outer layer of the seed coat. Using Illumina Hisequation 2000 sequencing technology, a total of 12 GB clean data, 116× coverage of coding sequences of B. napus, was achieved from seeds 26 d after pollination (DAP). It was assembled into 172,238 independent transcripts, and 55,637 unigenes. A total of 139 orthologous genes of Arabidopsis transparent testa (TT) genes were mapped in silico to 19 chromosomes of B. napus. Only 49 of the TT orthologous genes are transcribed in seeds. However transcription of all orthologs was independent of embryonal control of seed coat color. Only 55 genes were found to be differentially expressed between brown seeds and the yellow mutant. Of these 55, 50 were upregulated and five were downregulated in yellow seeds as compared to their brown counterparts. By KEGG classification, 14 metabolic pathways were significantly enriched. Of these, five pathways: phenylpropanoid biosynthesis, cyanoamino acid metabolism, plant hormone signal transduction, metabolic pathways, and biosynthesis of secondary metabolites, were related with seed coat pigmentation. Free amino acid quantification showed that Ala and Phe were present at higher levels in the embryos of yellow seeds as compared to those of brown seeds. This increase was not observed in the seed coat. Moreover, the excess amount of free Ala was exactly twice that of Phe in the embryo. The pigment substrate chalcone is synthesized from two molecules of Ala and one molecule of Phe. The correlation between accumulation of Ala and Phe, and disappearance of pigment in the yellow seeded mutant, suggests that embryonal control of seed coat color is related with Phe and Ala metabolism in the embryo of B. napus. PMID:26896439
Progress in wet-coated organic light-emitting devices for lighting
NASA Astrophysics Data System (ADS)
Liu, Jie; Ye, Qing; Lewis, Larry N.; Duggal, Anil R.
2007-09-01
Here we present recent progress in developing efficient wet-coated organic light-emitting devices (OLEDs) for lighting applications. In particular, we describe a novel approach for building efficient wet-coated dye-doped blue phosphorescent devices. Further, a novel approach for achieving arbitrary emission patterning for OLEDs is discussed. This approach utilizes a photo-induced chemical doping strategy for selectively activating charge injection materials, thus enabling devices with arbitrary emission patterning. This approach may provide a simple, low cost path towards specialty lighting and signage applications for OLED technology.
Improved Sand-Compaction Method for Lost-Foam Metal Casting
NASA Technical Reports Server (NTRS)
Bakhtiyarov, Sayavur I.; Overfelt, Ruel A.
2008-01-01
An improved method of filling a molding flask with sand and compacting the sand around a refractory-coated foam mold pattern has been developed for incorporation into the lost-foam metal-casting process. In comparison with the conventional method of sand filling and compaction, this method affords more nearly complete filling of the space around the refractory-coated foam mold pattern and more thorough compaction of the sand. In so doing, this method enables the sand to better support the refractory coat under metallostatic pressure during filling of the mold with molten metal.
Process for the Production of Star Tracklng [Tracking] Reticles
NASA Technical Reports Server (NTRS)
Smith, Wade O. (Inventor); Toft, Albert R. (Inventor)
1972-01-01
A method for the production of reticles, particularly those for use in outer space, wherein the product is a quartz base coated with highly adherent layers of chromium, chromium-silver, and silver vacuum deposited through a mask, and then coated with an electrodeposit of copper from a copper sulfate solution followed by an electrodeposit of black chromium. The masks are produced by coating a beryllium-copper alloy substrate with a positive working photoresist, developing the photoresist according to a pattern to leave a positive mask, plating uncoated areas with gold, removing the photoresist, coating the substrate with a negative working photoresist, developing the negative working photoresist to expose the base metal of the pattern, and chemically etching the unplated side of the pattern to produce the mask. The mask produced is then used in the vacuum deposition of: (1) chromium metal on the surface of a quartz base to obtain a highly adherent quartz-chromium interface; (2) silver on the chromium deposit, during the final stage of chromium deposit, to produce a silver chromium alloy layer; and (3) silver onto the surface of the alloy layer. The coated quartz base is then coated by electroplating utilizing an acid copper deposit followed by a black chromium electrodeposit to produce the product of the present invention.
Carrillo-Barral, Néstor; Matilla, Angel J; Rodríguez-Gacio, María Del Carmen; Iglesias-Fernández, Raquel
2018-03-01
Mannans but not endo-β-mannanases are mainly found in the mucilage layer of two Brassicaceae seeds. Nonetheless, mannanase mobilization from inner to outer seed layers cannot be ruled out. The contribution of endo-β-mannanase (MAN) genes to the germination of the wild-type Sisymbrium officinale and cultivated Brassica rapa (Brassicaceae) species has been explored. In both species, mannans have been localized to the imbibed external seed coat layer (mucilage) by fluorescence immunolocalization and MAN enzymatic activity increases in seeds as imbibition progresses, reaching a peak before 100% germination is achieved. The MAN gene families have been annotated and the expression of their members analyzed in vegetative and reproductive organs. In S. officinale and B. rapa, MAN2, MAN5, MAN6, and MAN7 transcripts accumulate upon seed imbibition. SoMAN7 is the most expressed MAN gene in S. officinale germinating seeds, as occurs with its ortholog in Arabidopsis thaliana, but in B. rapa, the most abundant transcripts are BrMAN2 and BrMAN5. These genes (MAN2, MAN5, MAN6, and MAN7) are localized, by mRNA in situ hybridization, to the micropylar at the endosperm layer and to the radicle in S. officinale, but in B. rapa, these mRNAs are faintly found to the micropylar living seed coat layer and are mainly present at the radicle tip and the vascular bundles. If the domestication process undergone by B. rapa is responsible for these different MAN expression patterns, upon germination remains to be elucidated. Since mannans and MAN genes are not spatially distributed in the same seed tissues, a movement of MAN enzymes that are synthesized with typical signal peptides from the embryo tissues to the mucilage layer (via apoplastic space) is necessary for the mannans to be hydrolyzed.
Domergue, Frédéric; Vishwanath, Sollapura J.; Joubès, Jérôme; Ono, Jasmine; Lee, Jennifer A.; Bourdon, Matthieu; Alhattab, Reem; Lowe, Christine; Pascal, Stéphanie; Lessire, René; Rowland, Owen
2010-01-01
Suberin is a protective hydrophobic barrier consisting of phenolics, glycerol, and a variety of fatty acid derivatives, including C18:0-C22:0 primary fatty alcohols. An eight-member gene family encoding alcohol-forming fatty acyl-coenzyme A reductases (FARs) has been identified in Arabidopsis (Arabidopsis thaliana). Promoter-driven expression of the β-glucuronidase reporter gene indicated that three of these genes, FAR1(At5g22500), FAR4(At3g44540), and FAR5(At3g44550), are expressed in root endodermal cells. The three genes were transcriptionally induced by wounding and salt stress. These patterns of gene expression coincide with known sites of suberin deposition. We then characterized a set of mutants with T-DNA insertions in FAR1, FAR4, or FAR5 and found that the suberin compositions of roots and seed coats were modified in each far mutant. Specifically, C18:0-OH was reduced in far5-1, C20:0-OH was reduced in far4-1, and C22:0-OH was reduced in far1-1. We also analyzed the composition of polymer-bound lipids of leaves before and after wounding and found that the basal levels of C18:0-C22:0 primary alcohols in wild-type leaves were increased by wounding. In contrast, C18:0-OH and C22:0-OH were not increased by wounding in far5-1 and far1-1 mutants, respectively. Heterologous expression of FAR1, FAR4, and FAR5 in yeast confirmed that they are indeed active alcohol-forming FARs with distinct, but overlapping, chain length specificities ranging from C18:0 to C24:0. Altogether, these results indicate that Arabidopsis FAR1, FAR4, and FAR5 generate the fatty alcohols found in root, seed coat, and wound-induced leaf tissue. PMID:20571114
Pieralini, Anelise R F; Benjamin, Camila M; Ribeiro, Ricardo Faria; Scaf, Gulnara; Adabo, Gelson Luis
2010-10-01
This study evaluated the effect of pattern coating with spinel-based investment Rematitan Ultra (RU) on the castability and internal porosity of commercially pure (CP) titanium invested into phosphate-bonded investments. The apparent porosity of the investment was also measured. Square patterns (15 × 15 × 0.3 mm(3)) were either coated with RU, or not and invested into the phosphate-bonded investments: Rematitan Plus (RP), Rema Exakt (RE), Castorit Super C (CA), and RU (control group). The castings were made in an Ar-arc vacuum-pressure machine. The castability area (mm(2) ) was measured by an image-analysis system (n = 10). For internal porosity, the casting (12 × 12 × 2 mm(3) ) was studied by the X-ray method, and the projected porous area percentage was measured by an image-analysis system (n = 10). The apparent porosity of the investment (n = 10) was measured in accordance with the ASTM C373-88 standard. Analysis of variance (One-way ANOVA) of castability was significant, and the Tukey test indicated that RU had the highest mean but the investing technique with coating increased the castability for all phosphate-bonded investments. The analysis of the internal porosity of the cast by the nonparametric test demonstrated that the RP, RE, and CA with coating and RP without coating did not differ from the control group (RU), while the CA and RE casts without coating were more porous. The one-way ANOVA of apparent porosity of the investment was significant, and the Tukey test showed that the means of RU (36.10%) and CA (37.22%) were higher than those of RP (25.91%) and RE (26.02%). Pattern coating with spinel-based material prior to phosphate-bonded investments can influence the castability and the internal porosity of CP Ti. © 2010 by The American College of Prosthodontists.
Plasma-Sprayed Titanium Patterns for Enhancing Early Cell Responses
NASA Astrophysics Data System (ADS)
Shi, Yunqi; Xie, Youtao; Pan, Houhua; Zheng, Xuebin; Huang, Liping; Ji, Fang; Li, Kai
2016-06-01
Titanium coating has been widely used as a biocompatible metal in biomedical applications. However, the early cell responses and long-term fixation of titanium implants are not satisfied. To obviate these defects, in this paper, micro-post arrays with various widths (150-1000 μm) and intervals (100-300 μm) were fabricated on the titanium substrate by template-assisted plasma spraying technology. In vitro cell culture experiments showed that MC3T3-E1 cells exhibited significantly higher osteogenic differentiation as well as slightly improved adhesion and proliferation on the micro-patterned coatings compared with the traditional one. The cell number on the pattern with 1000 µm width reached 130% after 6 days of incubation, and the expressions of osteopontin (OPN) as well as osteocalcin (OC) were doubled. No obvious difference was found in cell adhesion on various size patterns. The present micro-patterned coatings proposed a new modification method for the traditional plasma spraying technology to enhance the early cell responses and convenience for the bone in-growth.
Fabrication of 10 μm-scale conductive Cu patterns by selective laser sintering of Cu complex ink
NASA Astrophysics Data System (ADS)
Min, Hyungsuk; Lee, Byoungyoon; Jeong, Sooncheol; Lee, Myeongkyu
2017-02-01
A Cu complex ink was synthesized using copper formate as a precursor and its potential for laser patterning was investigated. The Cu ink was spin-coated onto a substrate and the coated film was space-selectively sintered using a nanosecond-pulsed ultraviolet laser. The unexposed Cu ink could be removed from the film by rinsing it with the dispersing agent used to synthesize the ink, disclosing a conductive Cu pattern. A minimum resistivity of 8.46×10-5 Ω cm was obtained for the Cu lines with 10-20 μm widths. The feasibility of this method for metallization was demonstrated by fabricating a complex Cu electric circuit on an indium tin oxide-coated glass substrate. The selective laser sintering approach provides a simple, cost-effective alternative to conventional lithography for the production of electrode or metallization patterns.
Gao, Bingbing; Liu, Hong; Gu, Zhongze
2014-12-23
We report a method for the bottom-up fabrication of paper-based capillary microchips by the blade coating of cellulose microfibers on a patterned surface. The fabrication process is similar to the paper-making process in which an aqueous suspension of cellulose microfibers is used as the starting material and is blade-coated onto a polypropylene substrate patterned using an inkjet printer. After water evaporation, the cellulose microfibers form a porous, hydrophilic, paperlike pattern that wicks aqueous solution by capillary action. This method enables simple, fast, inexpensive fabrication of paper-based capillary channels with both width and height down to about 10 μm. When this method is used, the capillary microfluidic chip for the colorimetric detection of glucose and total protein is fabricated, and the assay requires only 0.30 μL of sample, which is 240 times smaller than for paper devices fabricated using photolithography.
Small-Interfering RNA–Eluting Surfaces as a Novel Concept for Intravascular Local Gene Silencing
Nolte, Andrea; Walker, Tobias; Schneider, Martina; Kray, Oya; Avci-Adali, Meltem; Ziemer, Gerhard; Wendel, Hans Peter
2011-01-01
New drug-eluting stent (DES) methods have recently been demonstrated to improve outcomes of intravascular interventions. A novel technique is the design of gene-silencing stents that elute specific small-interfering RNAs (siRNAs) for better vascular wall regeneration. Although siRNAs used to alter gene expression have surpassed expectations in in vitro experiments, the functional and local delivery of siRNAs is still the major obstacle for the in vivo application of RNA interference. In this preliminary in vitro study we investigated a surface-immobilized siRNA delivery technique that would be readily adaptable for local intravascular applications in vivo. The transfection potency of gelatin coatings consisting of a specific siRNA complexed with polyethylenimine (PEI) was examined in primary human endothelial cells by flow cytometry and quantitative real-time polymerase chain reaction. Several media conditions, such as the presence or absence of serum during cultivation, were investigated. Furthermore, different siRNA and PEI amounts, as well as nitrogen/phosphate ratios, were tested for their transfection efficiency. Gelatin coatings consisting of PEI and siRNA against an exemplary endothelial adhesion molecule receptor achieved a significant knockdown of around 70%. The transfection efficiency of the coatings was not influenced by the presence of serum. The results of this preliminary study support the expectation that this novel coating may be favorable for local in vivo gene silencing (for example, when immobilized on stents or balloons for percutanous transluminal coronary angioplasty). However, further animal experiments are needed to confirm the translation into clinical practice. This intriguing technology leads the way to more sophisticated and individualized coatings for the post-DES era, toward silencing of genes involved in the pathway of intimal hyperplasia. PMID:21792480
Lee, Wonmok; Kim, Seulgi; Kim, Seulki; Kim, Jin-Ho; Lee, Hyunjung
2015-02-15
There are active researches on well ordered opal films due to their possible applications to various photonic devices. A recently developed slide coating method is capable of rapid fabrication of large area opal films from aqueous colloidal dispersion. In the current study, the slide coating of polystyrene colloidal dispersions in water/i-propanol (IPA) binary media is investigated. Under high IPA content in a dispersing medium, resulting opal film showed a deterioration of long range order, as well as a decreased film thickness due to dilution effect. From the binary liquid, the dried opal films exhibited the unprecedented topological groove patterns with varying periodic distances as a function of alcohol contents in the media. The groove patterns were consisted of the hierarchical structures of the terraced opal layers with periodic thickness variations. The origin of the groove patterns was attributed to a shear-induced periodic instability of colloidal concentration within a thin channel during the coating process which was directly converted to a groove patterns in a resulting opal film due to rapid evaporation of liquid. The groove periods of opal films were in the range of 50-500 μm, and the thickness differences between peak and valley of the groove were significantly large enough to be optically distinguishable, such that the coated films can be utilized as the optical grating film to disperse infra-red light. Utilizing a lowered hydrophilicity of water/IPA dispersant, an opal film could be successfully coated on a flexible Mylar film without significant dewetting problem. Copyright © 2014 Elsevier Inc. All rights reserved.
Renfree, Marilyn B; Shaw, Geoff
2014-01-01
The marsupial tammar wallaby has the longest period of embryonic diapause of any mammal. Reproduction in the tammar is seasonal, regulated by photoperiod and also lactation. Reactivation is triggered by falling daylength after the austral summer solstice in December. Young are born late January and commence a 9-10-month lactation. Females mate immediately after birth. The resulting conceptus develops over 6- 7 days to form a unilaminar blastocyst of 80-100 cells and enters lactationally, and later seasonally, controlled diapause. The proximate endocrine signal for reactivation is an increase in progesterone which alters uterine secretions. Since the diapausing blastocyst is surrounded by the zona and 2 other acellular coats, the mucoid layer and shell coat, the uterine signals that maintain or terminate diapause must involve soluble factors in the secretions rather than any direct cellular interaction between uterus and embryo. Our studies suggest involvement of a number of cytokines in the regulation of diapause in tammars. The endometrium secretes platelet activating factor (PAF) and leukaemia inhibitory factor, which increase after reactivation. Receptors for PAF are low on the blastocyst during diapause but are upregulated at reactivation. Conversely, there is endometrial expression of the muscle segment homeobox gene MSX2 throughout diapause, but it is rapidly downregulated at reactivation. These patterns are consistent with those observed in diapausing mice and mink after reactivation, despite the very different patterns of endocrine control of diapause in these 3 divergent species. These common patterns suggest a similar underlying mechanism for diapause, perhaps common to all mammals, but which is activated in only a few.
Sánchez-Navarro, J A; Reusken, C B; Bol, J F; Pallás, V
1997-12-01
Alfalfa mosaic virus (AMV) and Prunus necrotic ringspot virus (PNRSV) are tripartite positive-strand RNA plant viruses that encode functionally similar translation products. Although the two viruses are phylogenetically closely related, they infect a very different range of natural hosts. The coat protein (CP) gene, the movement protein (MP) gene or both genes in AMV RNA 3 were replaced by the corresponding genes of PNRSV. The chimeric viruses were tested for heterologous encapsidation, replication in protoplasts from plants transformed with AMV replicase genes P1 and P2 (P12 plants) and for cell-to-cell transport in P12 plants. The chimeric viruses exhibited basic competence for encapsidation and replication in P12 protoplasts and for a low level of cell-to-cell movement in P12 plants. The potential involvement of the MP gene in determining host specificity in ilarviruses is discussed.
Bajpai, Indu; Kim, Duk Yeon; Kyong-Jin, Jung; Song, In-Hwan; Kim, Sukyoung
2016-01-01
Ca-P and silicon based materials have become very popular as bone tissue engineering materials. In this study, water-glass (also known as sodium silicate glass) was coated on sintered hydroxyapatite (HA) and HA-TCP (TCP stands for tricalcium phosphate) samples and subsequently heat-treated at 600°C for 2 hrs. X-rays diffraction showed the presence of β- and α-TCP phases along with HA in the HA-TCP samples. Samples without coating, with water-glass coating, and heat-treated after water-glass coating were used to observe the adhesion and proliferation response of bone marrow derived-mesenchymal stem cells (MSCs). Cell culture was carried out for 4 hrs, 1 day, and 7 days. Interestingly, all samples showed similar response for cell adhesion and proliferation up to 7-day culture but fibronectin, E-cadherin, and osteogenic differentiation related genes (osteocalcin and osteopontin) were significantly induced in heat-treated water-glass coated HA-TCP samples. A water-glass coating on Ca-P samples was not found to influence the cell proliferation response significantly but activated some extracellular matrix genes and induced osteogenic differentiation in the MSCs.
Deep sequencing reveals microbiota dysbiosis of tongue coat in patients with liver carcinoma.
Lu, Haifeng; Ren, Zhigang; Li, Ang; Zhang, Hua; Jiang, Jianwen; Xu, Shaoyan; Luo, Qixia; Zhou, Kai; Sun, Xiaoli; Zheng, Shusen; Li, Lanjuan
2016-09-08
Liver carcinoma (LC) is a common malignancy worldwide, associated with high morbidity and mortality. Characterizing microbiome profiles of tongue coat may provide useful insights and potential diagnostic marker for LC patients. Herein, we are the first time to investigate tongue coat microbiome of LC patients with cirrhosis based on 16S ribosomal RNA (rRNA) gene sequencing. After strict inclusion and exclusion criteria, 35 early LC patients with cirrhosis and 25 matched healthy subjects were enrolled. Microbiome diversity of tongue coat in LC patients was significantly increased shown by Shannon, Simpson and Chao 1 indexes. Microbiome on tongue coat was significantly distinguished LC patients from healthy subjects by principal component analysis. Tongue coat microbial profiles represented 38 operational taxonomic units assigned to 23 different genera, distinguishing LC patients. Linear discriminant analysis (LDA) effect size (LEfSe) reveals significant microbial dysbiosis of tongue coats in LC patients. Strikingly, Oribacterium and Fusobacterium could distinguish LC patients from healthy subjects. LEfSe outputs show microbial gene functions related to categories of nickel/iron_transport, amino_acid_transport, energy produced system and metabolism between LC patients and healthy subjects. These findings firstly identify microbiota dysbiosis of tongue coat in LC patients, may providing novel and non-invasive potential diagnostic biomarker of LC.
Deep sequencing reveals microbiota dysbiosis of tongue coat in patients with liver carcinoma
NASA Astrophysics Data System (ADS)
Lu, Haifeng; Ren, Zhigang; Li, Ang; Zhang, Hua; Jiang, Jianwen; Xu, Shaoyan; Luo, Qixia; Zhou, Kai; Sun, Xiaoli; Zheng, Shusen; Li, Lanjuan
2016-09-01
Liver carcinoma (LC) is a common malignancy worldwide, associated with high morbidity and mortality. Characterizing microbiome profiles of tongue coat may provide useful insights and potential diagnostic marker for LC patients. Herein, we are the first time to investigate tongue coat microbiome of LC patients with cirrhosis based on 16S ribosomal RNA (rRNA) gene sequencing. After strict inclusion and exclusion criteria, 35 early LC patients with cirrhosis and 25 matched healthy subjects were enrolled. Microbiome diversity of tongue coat in LC patients was significantly increased shown by Shannon, Simpson and Chao 1 indexes. Microbiome on tongue coat was significantly distinguished LC patients from healthy subjects by principal component analysis. Tongue coat microbial profiles represented 38 operational taxonomic units assigned to 23 different genera, distinguishing LC patients. Linear discriminant analysis (LDA) effect size (LEfSe) reveals significant microbial dysbiosis of tongue coats in LC patients. Strikingly, Oribacterium and Fusobacterium could distinguish LC patients from healthy subjects. LEfSe outputs show microbial gene functions related to categories of nickel/iron_transport, amino_acid_transport, energy produced system and metabolism between LC patients and healthy subjects. These findings firstly identify microbiota dysbiosis of tongue coat in LC patients, may providing novel and non-invasive potential diagnostic biomarker of LC.
Chang, Hao; Ren, Ke-feng; Zhang, He; Wang, Jin-lei; Wang, Bai-liang; Ji, Jian
2015-02-01
Vascular gene-eluting stents (GES) is a promising strategy for treatment of cardiovascular disease. Very recently, we have proved that the (protamine sulfate/plasmid DNA encoding hepatocyte growth factor) (PrS/HGF-pDNA) multilayer can serve as a powerful tool for enhancing competitiveness of endothelial cell over smooth muscle cell, which opens perspectives for the regulation of intercellular competitiveness in the field of interventional therapy. However, before the gene multilayer films could be used in vascular stents for real clinical application, the preservation of gene bioactivity during the industrial sterilization and the hemocompatibility of film should be taken into account. Actually, both are long been ignored issues in the field of gene coating for GES. In this study, we demonstrate that the (PrS/HGF-pDNA) multilayer film exhibits the good gene-protecting abilities, which is confirmed by using the industrial sterilizations (gamma irradiation and ethylene oxide) and a routine storage condition (dry state at 4°C for 30 days). Furthermore, hemocompatible measurements (such as platelet adhesion and whole blood coagulation) and antibacterial assays (bacteria adhesion and growth inhibition) indicate the good anticoagulation and antibacterial properties of the (PrS/HGF-pDNA) multilayer film. The in vivo preliminary data of angiography and histological analysis suggest that the (PrS/HGF-pDNA) multilayer coated stent can reduce the in-stent restenosis. This work reveals that the (PrS/HGF-pDNA) multilayer film could be a promising candidate as coating for GES, which is of great potential in future clinic application. © 2014 Wiley Periodicals, Inc.
Desert Beetle-Inspired Superwettable Patterned Surfaces for Water Harvesting.
Yu, Zhenwei; Yun, Frank F; Wang, Yanqin; Yao, Li; Dou, Shixue; Liu, Kesong; Jiang, Lei; Wang, Xiaolin
2017-09-01
With the impacts of climate change and impending crisis of clean drinking water, designing functional materials for water harvesting from fog with large water capacity has received much attention in recent years. Nature has evolved different strategies for surviving dry, arid, and xeric conditions. Nature is a school for human beings. In this contribution, inspired by the Stenocara beetle, superhydrophilic/superhydrophobic patterned surfaces are fabricated on the silica poly(dimethylsiloxane) (PDMS)-coated superhydrophobic surfaces using a pulsed laser deposition approach with masks. The resultant samples with patterned wettability demonstrate water-harvesting efficiency in comparison with the silica PDMS-coated superhydrophobic surface and the Pt nanoparticles-coated superhydrophilic surface. The maximum water-harvesting efficiency can reach about 5.3 g cm -2 h -1 . Both the size and the percentage of the Pt-coated superhydrophilic square regions on the patterned surface affect the condensation and coalescence of the water droplet, as well as the final water-harvesting efficiency. The present water-harvesting strategy should provide an avenue to alleviate the water crisis facing mankind in certain arid regions of the world. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Zhao, L; Ashraf, M A
2015-12-01
The main reason for biomaterial related refractory infections is biofilm formation caused by bacterial adhesion on the surface of materials. Silver-hydroxyapatite (Ag/HA) nanocomposite coating can inhibit the formation of biofilm, but its mechanism is not clear. In order to clarify the mechanism, the amounts of biofilm on the Ag/HA composite coating and HA coating were determined, the release rates of silver nanoparticles in simulated body fluid (SBF) were detected by atomic absorption spectrometry, and the expression values of atlE , fbe , sap , iapB genes of Staphylococcus aureus were studied when they grew on Ag/HA composite coating and HA coating. The amount of the biofilm on the Ag/HA composite coating was significantly less than that on the HA coating, and the bacterial adhesion was decreased. The silver nanoparticles were released continuously in SBF and the release rate decreased gradually with time. The expression values of atlE , fbe and sap were high in the initial stage of adhesion and the expression value of iapB was high in the colonies-gathering stage in the control group, but they were all significantly inhibited in the presence of Ag. These results indicated that the main antibacterial effect of Ag/HA composite coating was achieved by the release of silver nanoparticles. The addition of Ag inhibited the expression of genes related to biofilm formation, which in turn inhibited the formation of biofilms. This provided theoretical support for the clinical application of Ag/HA composite coating.
The detection of HBV DNA with gold-coated iron oxide nanoparticle gene probes
NASA Astrophysics Data System (ADS)
Xi, Dong; Luo, XiaoPing; Lu, QiangHua; Yao, KaiLun; Liu, ZuLi; Ning, Qin
2008-03-01
Gold-coated iron oxide nanoparticle Hepatitis B virus (HBV) DNA probes were prepared, and their application for HBV DNA measurement was studied. Gold-coated iron oxide nanoparticles were prepared by the citrate reduction of tetra-chloroauric acid in the presence of iron oxide nanoparticles which were added as seeds. With a fluorescence-based method, the maximal surface coverage of hexaethiol 30-mer oligonucleotides and the maximal percentage of hybridization strands on gold-coated iron oxide nanoparticles were (120 ± 8) oligonucleotides per nanoparticle, and (14 ± 2%), respectively, which were comparable with those of (132 ± 10) and (22 ± 3%) in Au nanoparticle groups. Large network aggregates were formed when gold-coated iron oxide nanoparticle HBV DNA gene probe was applied to detect HBV DNA molecules as evidenced by transmission electron microscopy and the high specificity was verified by blot hybridization. Our results further suggested that detecting DNA with iron oxide nanoparticles and magnetic separator was feasible and might be an alternative effective method.
Long-term evolution of the Luteoviridae: time scale and mode of virus speciation.
Pagán, Israel; Holmes, Edward C
2010-06-01
Despite their importance as agents of emerging disease, the time scale and evolutionary processes that shape the appearance of new viral species are largely unknown. To address these issues, we analyzed intra- and interspecific evolutionary processes in the Luteoviridae family of plant RNA viruses. Using the coat protein gene of 12 members of the family, we determined their phylogenetic relationships, rates of nucleotide substitution, times to common ancestry, and patterns of speciation. An associated multigene analysis enabled us to infer the nature of selection pressures and the genomic distribution of recombination events. Although rates of evolutionary change and selection pressures varied among genes and species and were lower in some overlapping gene regions, all fell within the range of those seen in animal RNA viruses. Recombination breakpoints were commonly observed at gene boundaries but less so within genes. Our molecular clock analysis suggested that the origin of the currently circulating Luteoviridae species occurred within the last 4 millennia, with intraspecific genetic diversity arising within the last few hundred years. Speciation within the Luteoviridae may therefore be associated with the expansion of agricultural systems. Finally, our phylogenetic analysis suggested that viral speciation events tended to occur within the same plant host species and country of origin, as expected if speciation is largely sympatric, rather than allopatric, in nature.
Ataie Kachoie, Elham; Behjatnia, Seyed Ali Akbar; Kharazmi, Sara
2018-01-01
It has already been demonstrated that a betasatellite associated with cotton leaf curl Multan virus (CLCuMB) can be used as a plant and animal gene delivery vector to plants. To examine the ability of CLCuMB as a tool to transfer coat protein genes of HIV-1 to plants, two recombinant CLCuMB constructs in which the CLCuMB βC1 ORF was replaced with two HIV-1 genes fractions including a 696 bp DNA fragment related to the HIV-1 p24 gene and a 1501 bp DNA fragment related to the HIV-1 gag gene were constructed. Gag is the HIV-1 coat protein gene and p24 is a component of the particle capsid. Gag and p24 are used for vaccine production. Recombinant constructs were inoculated to Nicotiana glutinosa and N. benthamiana plants in the presence of an Iranian isolate of Tomato yellow leaf curl virus (TYLCV-[Ab]) as a helper virus. PCR analysis of inoculated plants indicated that p24 gene was successfully replicated in inoculated plants, but the gag gene was not. Real-time PCR and ELISA analysis of N. glutinosa and N. benthamiana plants containing the replicative forms of recombinant construct of CLCuMB/p24 indicated that p24 was expressed in these plants. This CLCuMB-based expression system offers the possibility of mass production of recombinant HIV-1 p24 protein in plants.
Desai, Rajen U; Saffra, Norman A; Krishna, Rati P; Rosenberg, Steven E
2011-01-01
The authors describe a girl diagnosed as having Coats' disease, Turner syndrome (45X karyotype), and type 1 von Willebrand disease. She tested negative for the Norrie disease pseudoglioma (NDP) gene located on the X-chromosome, which has been suspected of contributing to Coats' disease. Copyright 2010, SLACK Incorporated.
van der Stok, Johan; Lozano, Daniel; Chai, Yoke Chin; Amin Yavari, Saber; Bastidas Coral, Angela P; Verhaar, Jan A N; Gómez-Barrena, Enrique; Schrooten, Jan; Jahr, Holger; Zadpoor, Amir A; Esbrit, Pedro; Weinans, Harrie
2015-05-01
A promising bone graft substitute is porous titanium. Porous titanium, produced by selective laser melting (SLM), can be made as a completely open porous and load-bearing scaffold that facilitates bone regeneration through osteoconduction. In this study, the bone regenerative capacity of porous titanium is improved with a coating of osteostatin, an osteoinductive peptide that consists of the 107-111 domain of the parathyroid hormone (PTH)-related protein (PTHrP), and the effects of this osteostatin coating on bone regeneration were evaluated in vitro and in vivo. SLM-produced porous titanium received an alkali-acid-heat treatment and was coated with osteostatin through soaking in a 100 nM solution for 24 h or left uncoated. Osteostatin-coated scaffolds contained ∼0.1 μg peptide/g titanium, and in vitro 81% was released within 24 h. Human periosteum-derived osteoprogenitor cells cultured on osteostatin-coated scaffolds did not induce significant changes in osteogenic (alkaline phosphatase [ALP], collagen type 1 [Col1], osteocalcin [OCN], runt-related transcription factor 2 [Runx2]), or angiogenic (vascular endothelial growth factor [VEGF]) gene expression; however, it resulted in an upregulation of osteoprotegerin (OPG) gene expression after 24 h and a lower receptor activator of nuclear factor kappa-B ligand (RankL):OPG mRNA ratio. In vivo, osteostatin-coated, porous titanium implants increased bone regeneration in critical-sized cortical bone defects (p=0.005). Bone regeneration proceeded until 12 weeks, and femurs grafted with osteostatin-coated implants and uncoated implants recovered, respectively, 66% and 53% of the original femur torque strength (97±31 and 77±53 N·mm, not significant). In conclusion, the osteostatin coating improved bone regeneration of porous titanium. This effect was initiated after a short burst release and might be related to the observed in vitro upregulation of OPG gene expression by osteostatin in osteoprogenitor cells. Long-term beneficial effects of osteostatin-coated, porous titanium implants on bone regeneration or mechanical strength were not established here and may require optimization of the pace and dose of osteostatin release.
Improvements To Micro Contact Performance And Reliability
2016-12-22
BAKE : □ 1 min 110°C hot plate bake OPTIONAL - For Grayscale Lithography: 1818 COAT: □ Flood wafer with 1818 □ 4 sec spread at 500 rpm...30 sec spin at 4,000 rpm, ramp=200 □ 75 sec 110°C hot plate bake GRAYSCALE PATTERNING: □ Follow grayscale patterning process for patterns...8217 □ 2 min 200°C hot plate bake 1818 COAT: □ Flood wafer with 1818 □ 4 sec spread at 500 rpm □ 30 sec spin at 4,000 rpm, ramp=200 □ 75 sec 110
Dinant, S; Lot, H; Albouy, J; Kuziak, C; Meyer, M; Astier-Manifacier, S
1991-01-01
DNA complementary to the 3' terminal 1651 nucleotides of the genome of the common strain of lettuce mosaic virus (LMV-O) has been cloned and sequenced. Microsequencing of the N-terminus enabled localization of the coat protein gene in this sequence. It showed also that the LMV coat protein coding region is at the 3' end of the genome, and that the coat protein is processed from a larger protein by cleavage at an unusual Q/V dipeptide between the polymerase and the coat protein. This is the first report of such a site for cleavage of a potyvirus polyprotein, where only Q/A, Q/S, and Q/G cleavage sites have been reported. The LMV coat protein gene encodes a 278 amino acid polypeptide with a calculated Mr of 31,171 and is flanked by a region which has a high degree of homology with the putative polymerase and a 3' untranslated region of 211 nucleotides in length. Percentage of homology with the coat protein of other potyviruses confirms that LMV is a distinct member of this group. Moreover, amino acid homologies noticed with the coat protein of potexvirus, bymovirus, and carlavirus elongated plant viruses suggest a functional significance for the conserved domains.
Stahl, Ullrich; Voigt, Achim; Dirschka, Marian; Barié, Nicole; Richter, Christiane; Waldbaur, Ansgar; Gruhl, Friederike J; Rapp, Bastian E; Rapp, Michael; Länge, Kerstin
2017-11-03
Arrays with polymer-coated acoustic sensors, such as surface acoustic wave (SAW) and surface transverse wave (STW) sensors, have successfully been applied for a variety of gas sensing applications. However, the stability of the sensors' polymer coatings over a longer period of use has hardly been investigated. We used an array of eight STW resonator sensors coated with different polymers. This sensor array was used at semi-annual intervals for a three-year period to detect organic solvent vapors of three different chemical classes: a halogenated hydrocarbon (chloroform), an aliphatic hydrocarbon (octane), and an aromatic hydrocarbon (xylene). The sensor signals were evaluated with regard to absolute signal shifts and normalized signal shifts leading to signal patterns characteristic of the respective solvent vapors. No significant time-related changes of sensor signals or signal patterns were observed, i.e., the polymer coatings kept their performance during the course of the study. Therefore, the polymer-coated STW sensors proved to be robust devices which can be used for detecting organic solvent vapors both qualitatively and quantitatively for several years.
Zhao, L; Ashraf, MA
2015-01-01
ABSTRACT Background: The main reason for biomaterial related refractory infections is biofilm formation caused by bacterial adhesion on the surface of materials. Silver-hydroxyapatite (Ag/HA) nanocomposite coating can inhibit the formation of biofilm, but its mechanism is not clear. Material and Method: In order to clarify the mechanism, the amounts of biofilm on the Ag/HA composite coating and HA coating were determined, the release rates of silver nanoparticles in simulated body fluid (SBF) were detected by atomic absorption spectrometry, and the expression values of atlE, fbe, sap, iapB genes of Staphylococcus aureus were studied when they grew on Ag/HA composite coating and HA coating. Results: The amount of the biofilm on the Ag/HA composite coating was significantly less than that on the HA coating, and the bacterial adhesion was decreased. The silver nanoparticles were released continuously in SBF and the release rate decreased gradually with time. The expression values of atlE, fbe and sap were high in the initial stage of adhesion and the expression value of iapB was high in the colonies-gathering stage in the control group, but they were all significantly inhibited in the presence of Ag. Conclusion: These results indicated that the main antibacterial effect of Ag/HA composite coating was achieved by the release of silver nanoparticles. The addition of Ag inhibited the expression of genes related to biofilm formation, which in turn inhibited the formation of biofilms. This provided theoretical support for the clinical application of Ag/HA composite coating. PMID:27400164
Mapping the non-darkening trait from 'Wit-rood boontje' in bean (Phaseolus vulgaris).
Erfatpour, M; Navabi, A; Pauls, K P
2018-06-01
A QTL for non-darkening seed coat from 'Wit-rood boontje' was mapped in pinto bean population on chromosome Pv10, comprising 40 candidate genes. The seed coat colour darkens with age in some market classes of dry beans (Phaseolus vulgaris), including pinto bean. Beans with darkened seed coats are discounted in the market place, since they are believed to be associated with lower nutritional quality, increased cooking time, and decreased palatability. The objective of this research was to map a non-darkening gene from a cranberry-like bean 'Wit-rood boontje' using a recombinant inbred line population, derived from a cross between 'Wit-rood boontje' and a slow-darkening pinto bean (1533-15). The population was characterized for seed phenotype and genotyped with an Illumina BeadChip. A genetic linkage map was constructed with 1327 informative SNP markers plus an STS marker (OL4S 500 ) and an SSR marker (Pvsd-0028), previously associated with the J gene and Sd gene, respectively, as well as non-darkening and slow-darkening phenotypes. The linkage map spanned 1253.2 cM over 11 chromosomes. A major QTL for the non-darkening trait was flanked by SNP 715646341 and SNP 715646348 on chromosome Pv10. The region, which spanned 13.2 cM, explained 48% of the phenotypic variation for seed coat darkening. Forty candidate genes were identified in the QTL interval. This information can be used to develop a gene-based marker to facilitate breeding non-darkening pinto beans and may lead to a better understanding of the molecular mechanism for the postharvest darkening phenomenon in pinto bean.
NASA Astrophysics Data System (ADS)
Yamamoto, Kazuya; Takaoka, Toshimitsu; Fukui, Hidetoshi; Haruta, Yasuyuki; Yamashita, Tomoya; Kitagawa, Seiichiro
2016-03-01
In general, thin-film coating process is widely applied on optical lens surface as anti-reflection function. In normal production process, at first lens is manufactured by molding, then anti-reflection is added by thin-film coating. In recent years, instead of thin-film coating, sub-wavelength structures adding on surface of molding die are widely studied and development to keep anti-reflection performance. As merits, applying sub-wavelength structure, coating process becomes unnecessary and it is possible to reduce man-hour costs. In addition to cost merit, these are some technical advantages on this study. Adhesion of coating depends on material of plastic, and it is impossible to apply anti-reflection function on arbitrary surface. Sub-wavelength structure can solve both problems. Manufacturing method of anti-reflection structure can be divided into two types mainly. One method is with the resist patterning, and the other is mask-less method that does not require patterning. What we have developed is new mask-less method which is no need for resist patterning and possible to impart an anti-reflection structure to large area and curved lens surface, and can be expected to apply to various market segments. We report developed technique and characteristics of production lens.
(Mechanisms of inhibition of viral replication in plants)
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
1992-01-01
Progress is described concerning genetic mapping CMV movement genes for CMV coat protein in squash and ToMV gene in tomato. These gene products appear to be involved in resistance to squash and tomato mosaic viruses respectively.
1983-08-01
34.-0 " -4 to -0 ) i ’ to-0 - 0-1J :x0. tf1 0 0 * *4-0 0- - C -4- - t)0o U 4- fa -- Etot 0 In 00)- r 4- a..- - D 4- 0 41 0 --- 0). S- E4JaW 4) 4- CJ - ea... valves ). Figure B2. Icing patterns, copolymer-coated surface left, uncoated right, continuous sheet. 17 Figure B3. Icing pattern, copolymer-coated
The opportunity and challenge of spin coat based nanoimprint lithography
NASA Astrophysics Data System (ADS)
Jung, Wooyung; Cho, Jungbin; Choi, Eunhyuk; Lim, Yonghyun; Bok, Cheolkyu; Tsuji, Masatoshi; Kobayashi, Kei; Kono, Takuya; Nakasugi, Tetsuro
2017-03-01
Since multi patterning with spacer was introduced in NAND flash memory1, multi patterning with spacer has been a promising solution to overcome the resolution limit. However, the increase in process cost of multi patterning with spacer must be a serious burden to device manufacturers as half pitch of patterns gets smaller.2, 3 Even though Nano Imprint Lithography (NIL) has been considered as one of strong candidates to avoid cost issue of multi patterning with spacer, there are still negative viewpoints; template damage induced from particles between template and wafer, overlay degradation induced from shear force between template and wafer, and throughput loss induced from dispensing and spreading resist droplet. Jet and Flash Imprint Lithography (J-FIL4, 5, 6) has contributed to throughput improvement, but still has these above problems. J-FIL consists of 5 steps; dispense of resist droplets on wafer, imprinting template on wafer, filling the gap between template and wafer with resist, UV curing, and separation of template from wafer. If dispensing resist droplets by inkjet is replaced with coating resist at spin coater, additional progress in NIL can be achieved. Template damage from particle can be suppressed by thick resist which is spin-coated at spin coater and covers most of particles on wafer, shear force between template and wafer can be minimized with thick resist, and finally additional throughput enhancement can be achieved by skipping dispense of resist droplets on wafer. On the other hand, spin-coat-based NIL has side effect such as pattern collapse which comes from high separation energy of resist. It is expected that pattern collapse can be improved by the development of resist with low separation energy.
Early development of fern gametophytes in microgravity
NASA Technical Reports Server (NTRS)
Roux, Stanley J.; Chatterjee, Ani; Hillier, Sheila; Cannon, Tom
2003-01-01
Dormant spores of the fern Ceratopteris richardii were flown on Shuttle mission STS-93 to evaluate the effects of micro-g on their development and on their pattern of gene expression. Prior to flight the spores were sterilized and sown into one of two environments: (1) Microscope slides in a video-microscopy module; and (2) Petri dishes. All spores were then stored in darkness until use. Spore germination was initiated on orbit after exposure to light. For the spores on microscope slides, cell level changes were recorded through the clear spore coat of the spores by video microscopy. After their exposure to light, spores in petri dishes were frozen in orbit at four different time points during which on earth gravity fixes the polarity of their development. Spores were then stored frozen in Biological Research in Canister units until recovery on earth. The RNAs from these cells and from 1-g control cells were extracted and analyzed on earth after flight to assay changes in gene expression. Video microscopy results revealed that the germinated spores developed normally in microgravity, although the polarity of their development, which is guided by gravity on earth, was random in space. Differential Display-PCR analyses of RNA extracted from space-flown cells showed that there was about a 5% change in the pattern of gene expression between cells developing in micro-g compared to those developing on earth. c2002 Published by Elsevier Science Ltd on behalf of COSPAR.
ISHIKAWA, Akira; SUGIYAMA, Makoto; HONDO, Eiichi; KINOSHITA, Keiji; YAMAGISHI, Yuki
2015-01-01
Oca2p-cas (oculocutaneous albinism II; pink-eyed dilution castaneus) is a coat color mutant gene on mouse chromosome 7 that arose spontaneously in wild Mus musculus castaneus mice. Mice homozygous for Oca2p-cas usually exhibit pink eyes and gray coat hair on the non-agouti genetic background, and this ordinary phenotype remains unchanged throughout life. During breeding of a mixed strain carrying this gene on the C57BL/6J background, we discovered a novel spontaneous mutation that causes darkening of the eyes and coat hair with aging. In this study, we developed a novel mouse model showing this unique phenotype. Gross observations revealed that the pink eyes and gray coat hair of the novel mutant young mice became progressively darker in color by approximately 3 months after birth. Light and transmission-electron microscopic observations revealed a marked increase in melanin pigmentation of coat hair shafts and choroid of the eye in the novel mice compared to that in the ordinary mice. Sequence analysis of Oca2p-cas revealed a 4.1-kb deletion involving exons 15 and 16 of its wild-type gene. However, there was no sequence difference between the two types of mutant mice. Mating experiments suggested that the novel mutant phenotype was not inherited in a simple fashion, due to incomplete penetrance. The novel spontaneous mutant mouse is the first example of progressive hair darkening animals and is an essential animal model for understanding of the regulation mechanisms of melanin biosynthesis with aging. PMID:25739360
Ishikawa, Akira; Sugiyama, Makoto; Hondo, Eiichi; Kinoshita, Keiji; Yamagishi, Yuki
2015-01-01
Oca2(p-cas) (oculocutaneous albinism II; pink-eyed dilution castaneus) is a coat color mutant gene on mouse chromosome 7 that arose spontaneously in wild Mus musculus castaneus mice. Mice homozygous for Oca2(p-cas) usually exhibit pink eyes and gray coat hair on the non-agouti genetic background, and this ordinary phenotype remains unchanged throughout life. During breeding of a mixed strain carrying this gene on the C57BL/6J background, we discovered a novel spontaneous mutation that causes darkening of the eyes and coat hair with aging. In this study, we developed a novel mouse model showing this unique phenotype. Gross observations revealed that the pink eyes and gray coat hair of the novel mutant young mice became progressively darker in color by approximately 3 months after birth. Light and transmission-electron microscopic observations revealed a marked increase in melanin pigmentation of coat hair shafts and choroid of the eye in the novel mice compared to that in the ordinary mice. Sequence analysis of Oca2(p-cas) revealed a 4.1-kb deletion involving exons 15 and 16 of its wild-type gene. However, there was no sequence difference between the two types of mutant mice. Mating experiments suggested that the novel mutant phenotype was not inherited in a simple fashion, due to incomplete penetrance. The novel spontaneous mutant mouse is the first example of progressive hair darkening animals and is an essential animal model for understanding of the regulation mechanisms of melanin biosynthesis with aging.
Gibberellin induces alpha-amylase gene in seed coat of Ipomoea nil immature seeds.
Nakajima, Masatoshi; Nakayama, Akira; Xu, Zheng-Jun; Yamaguchi, Isomaro
2004-03-01
Two full-length cDNAs encoding gibberellin 3-oxidases, InGA3ox1 and InGA3ox2, were cloned from developing seeds of morning glory (Ipomoea nil (Pharbitis nil) Choisy cv. Violet) with degenerate-PCR and RACEs. The RNA-blot analysis for these clones revealed that the InGA3ox2 gene was organ-specifically expressed in the developing seeds at 6-18 days after anthesis. In situ hybridization showed the signals of InGA3ox2 mRNA in the seed coat, suggesting that active gibberellins (GAs) were synthesized in the tissue, although no active GA was detected there by immunohistochemistry. In situ hybridization analysis for InAmy1 (former PnAmy1) mRNA showed that InAmy1 was also synthesized in the seed coat. Both InGA3ox2 and InAmy1 genes were expressed spatially overlapped without a clear time lag, suggesting that both active GAs and InAmy1 were synthesized almost simultaneously in seed coat and secreted to the integument. These observations support the idea that GAs play an important role in seed development by inducing alpha-amylase.
Egri, Adám; Blahó, Miklós; Kriska, György; Farkas, Róbert; Gyurkovszky, Mónika; Akesson, Susanne; Horváth, Gábor
2012-03-01
The characteristic striped appearance of zebras has provoked much speculation about its function and why the pattern has evolved, but experimental evidence is scarce. Here, we demonstrate that a zebra-striped horse model attracts far fewer horseflies (tabanids) than either homogeneous black, brown, grey or white equivalents. Such biting flies are prevalent across Africa and have considerable fitness impact on potential mammalian hosts. Besides brightness, one of the likely mechanisms underlying this protection is the polarization of reflected light from the host animal. We show that the attractiveness of striped patterns to tabanids is also reduced if only polarization modulations (parallel stripes with alternating orthogonal directions of polarization) occur in horizontal or vertical homogeneous grey surfaces. Tabanids have been shown to respond strongly to linearly polarized light, and we demonstrate here that the light and dark stripes of a zebra's coat reflect very different polarizations of light in a way that disrupts the attractiveness to tabanids. We show that the attractiveness to tabanids decreases with decreasing stripe width, and that stripes below a certain size are effective in not attracting tabanids. Further, we demonstrate that the stripe widths of zebra coats fall in a range where the striped pattern is most disruptive to tabanids. The striped coat patterns of several other large mammals may also function in reducing exposure to tabanids by similar mechanisms of differential brightness and polarization of reflected light. This work provides an experimentally supported explanation for the underlying mechanism leading to the selective advantage of a black-and-white striped coat pattern.
Li, Hong; Chen, Chen; Ge, Yunsheng; Chen, Shiyi
2014-05-01
To enhance graft ligamentization after anterior cruciate ligament (ACL) reconstruction, human fibronectin (FN) was coated on polyethylene terephthalate (PET) ligaments by spray painting. The FN-coated PET ligaments were investigated in vitro using rat mesenchymal stromal cells (MSCs). MSCs cultured on FN-coated grafts resulted in similar cell densities and amounts of proliferating cells with control grafts without coating. The FN-coated group not only gave rise to MSC-derived collagen-like tissues but also enhanced the expression of collagen-I gene. Furthermore, rat ACL reconstruction models were used to evaluate the effect of the FN coating in vivo. The FN coating significantly promoted new ligament tissue regeneration into the graft fibers. In conclusion, sprayed FN coating had a positive effect to enhance graft ligamentization of PET artificial ligament.
Polymorphisms within the canine MLPH gene are associated with dilute coat color in dogs
Philipp, Ute; Hamann, Henning; Mecklenburg, Lars; Nishino, Seiji; Mignot, Emmanuel; Günzel-Apel, Anne-Rose; Schmutz, Sheila M; Leeb, Tosso
2005-01-01
Background Pinschers and other dogs with coat color dilution show a characteristic pigmentation phenotype. The fur colors are a lighter shade, e.g. silvery grey (blue) instead of black and a sandy color (Isabella fawn) instead of red or brown. In some dogs the coat color dilution is sometimes accompanied by hair loss and recurrent skin inflammation, the so called color dilution alopecia (CDA) or black hair follicular dysplasia (BHFD). In humans and mice a comparable pigmentation phenotype without any documented hair loss is caused by mutations within the melanophilin gene (MLPH). Results We sequenced the canine MLPH gene and performed a mutation analysis of the MLPH exons in 6 Doberman Pinschers and 5 German Pinschers. A total of 48 sequence variations was identified within and between the breeds. Three families of dogs showed co-segregation for at least one polymorphism in an MLPH exon and the dilute phenotype. No single polymorphism was identified in the coding sequences or at splice sites that is likely to be causative for the dilute phenotype of all dogs examined. In 18 German Pinschers a mutation in exon 7 (R199H) was consistently associated with the dilute phenotype. However, as this mutation was present in homozygous state in four dogs of other breeds with wildtype pigmentation, it seems unlikely that this mutation is truly causative for coat color dilution. In Doberman Pinschers as well as in Large Munsterlanders with BHFD, a set of single nucleotide polymorphisms (SNPs) around exon 2 was identified that show a highly significant association to the dilute phenotype. Conclusion This study provides evidence that coat color dilution is caused by one or more mutations within or near the MLPH gene in several dog breeds. The data on polymorphisms that are strongly associated with the dilute phenotype will allow the genetic testing of Pinschers to facilitate the breeding of dogs with defined coat colors and to select against Large Munsterlanders carrying BHFD. PMID:15960853
Polymorphisms within the canine MLPH gene are associated with dilute coat color in dogs.
Philipp, Ute; Hamann, Henning; Mecklenburg, Lars; Nishino, Seiji; Mignot, Emmanuel; Günzel-Apel, Anne-Rose; Schmutz, Sheila M; Leeb, Tosso
2005-06-16
Pinschers and other dogs with coat color dilution show a characteristic pigmentation phenotype. The fur colors are a lighter shade, e.g. silvery grey (blue) instead of black and a sandy color (Isabella fawn) instead of red or brown. In some dogs the coat color dilution is sometimes accompanied by hair loss and recurrent skin inflammation, the so called color dilution alopecia (CDA) or black hair follicular dysplasia (BHFD). In humans and mice a comparable pigmentation phenotype without any documented hair loss is caused by mutations within the melanophilin gene (MLPH). We sequenced the canine MLPH gene and performed a mutation analysis of the MLPH exons in 6 Doberman Pinschers and 5 German Pinschers. A total of 48 sequence variations was identified within and between the breeds. Three families of dogs showed co-segregation for at least one polymorphism in an MLPH exon and the dilute phenotype. No single polymorphism was identified in the coding sequences or at splice sites that is likely to be causative for the dilute phenotype of all dogs examined. In 18 German Pinschers a mutation in exon 7 (R199H) was consistently associated with the dilute phenotype. However, as this mutation was present in homozygous state in four dogs of other breeds with wildtype pigmentation, it seems unlikely that this mutation is truly causative for coat color dilution. In Doberman Pinschers as well as in Large Munsterlanders with BHFD, a set of single nucleotide polymorphisms (SNPs) around exon 2 was identified that show a highly significant association to the dilute phenotype. This study provides evidence that coat color dilution is caused by one or more mutations within or near the MLPH gene in several dog breeds. The data on polymorphisms that are strongly associated with the dilute phenotype will allow the genetic testing of Pinschers to facilitate the breeding of dogs with defined coat colors and to select against Large Munsterlanders carrying BHFD.
Gonzalez-Escobedo, Geoffrey
2013-01-01
Salmonella spp. are able to form biofilms on abiotic and biotic surfaces. In vivo studies in our laboratory have shown that Salmonella can form biofilms on the surfaces of cholesterol gallstones in the gallbladders of mice and human carriers. Biofilm formation on gallstones has been demonstrated to be a mechanism of persistence. The purpose of this work was to identify and evaluate Salmonella sp. cholesterol-dependent biofilm factors. Differential gene expression analysis between biofilms on glass or cholesterol-coated surfaces and subsequent quantitative real-time PCR (qRT-PCR) revealed that type 1 fimbria structural genes and a gene encoding a putative outer membrane protein (ycfR) were specifically upregulated in Salmonella enterica serovar Typhimurium biofilms grown on cholesterol-coated surfaces. Spatiotemporal expression of ycfR and FimA verified their regulation during biofilm development on cholesterol-coated surfaces. Surprisingly, confocal and scanning electron microscopy demonstrated that a mutant of type 1 fimbria structural genes (ΔfimAICDHF) and a ycfR mutant showed increased biofilm formation on cholesterol-coated surfaces. In vivo experiments using Nramp1+/+ mice harboring gallstones showed that only the ΔycfR mutant formed extensive biofilms on mouse gallstones at 7 and 21 days postinfection; ΔfimAICDHF was not observed on gallstone surfaces after the 7-day-postinfection time point. These data suggest that in Salmonella spp., wild-type type 1 fimbriae are important for attachment to and/or persistence on gallstones at later points of chronic infection, whereas YcfR may represent a specific potential natural inhibitor of initial biofilm formation on gallstones. PMID:23897604
Use of RecA protein to enrich for homologous genes in a genomic library
DOE Office of Scientific and Technical Information (OSTI.GOV)
Taidi-Laskowski, B.; Grumet, F.C.; Tyan, D.
1988-08-25
RecA protein-coated probe has been utilized to enrich genomic digests for desired genes in order to facilitate cloning from genomic libraries. Using a previously cloned HLA-B27 gene as the recA-coated enrichment probe, the authors obtained a mean 108x increase in the ratio of specific to nonspecific plaques in lambda libraries screened for B27 variant alleles of estimated 99% homology to the probe. Class I genes of lesser homology were less enriched. Loss of genomic DNA during the enrichment procedure can, however, restrict application of this technique whenever starting genomic DNA is very limited. Nevertheless, the impressive reduction in cloning effortmore » and material makes recA enrichment a useful new tool for cloning homologous genes from genomic DNA.« less
[Mechanisms of inhibition of viral replication in plants]. Progress report
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
1992-09-01
Progress is described concerning genetic mapping CMV movement genes for CMV coat protein in squash and ToMV gene in tomato. These gene products appear to be involved in resistance to squash and tomato mosaic viruses respectively.
Electrical Field Guided Electrospray Deposition for Production of Gradient Particle Patterns.
Yan, Wei-Cheng; Xie, Jingwei; Wang, Chi-Hwa
2018-06-06
Our previous work demonstrated the uniform particle pattern formation on the substrates using electrical field guided electrospray deposition. In this work, we reported for the first time the fabrication of gradient particle patterns on glass slides using an additional point, line, or bar electrode based on our previous electrospray deposition configuration. We also demonstrated that the polydimethylsiloxane (PDMS) coating could result in the formation of uniform particle patterns instead of gradient particle patterns on glass slides using the same experimental setup. Meanwhile, we investigated the effect of experimental configurations on the gradient particle pattern formation by computational simulation. The simulation results are in line with experimental observations. The formation of gradient particle patterns was ascribed to the gradient of electric field and the corresponding focusing effect. Cell patterns can be formed on the particle patterns deposited on PDMS-coated glass slides. The formed particle patterns hold great promise for high-throughput screening of biomaterial-cell interactions and sensing.
[Virus resistance in transgenic watermelon plants containing a WMV-2 coat protein gene].
Wang, Hui-Zhong; Zhao, Pei-Jie; Xu, Ji-Chen; Zhao, Huai; Zhang, Hong-Sheng
2003-01-01
Virus disease is a major cause that affects the quality and output of watermelon which is an important fruit in summer. So it is really urgent to develop disease resistance plants. But it takes a long time to breed such plants in conventional ways, and it is very difficult to get ideal result. With the development of plant genetic engineering, new ways have been found to breed plants with disease resistance. By using plant transgenic technique, much progress was been made in plant improvement. There are many successful cases of transgenic plants against corresponding virus disease through transferring coat protein gene. This paper reports the results of inheritance, segregation, expression of WMV-2 coat protein gene in inbred transgenic watermelon and its resistance to virus. Through PCR analysis of inbred plants, we found WMV-2 coat protein gene in the genome of progeny R1 separated with 3:1. After successive selection and identification of 4 generations, 8 transgenic pure lines with almost the same agronomic traits were obtained from 3 independent transformants of T7, T11 and T32. The result of Western blotting shows all 3 different transgenic lines of R4T7-1, R4T11-3 and R4T32-7 can produce coat protein. Disease resistance experiment on transgenic plants with WMV-2 shows that, compared with the control groups, transgenic plants can delay the disease infection and reduce the incidence and the symptoms of virus disease. And the transgenic line R4T32-7 expressed high resistance to infection by WMV-2, which lays a foundation for breeding of disease resistant varieties through plant transgenic technique.
NASA Astrophysics Data System (ADS)
Li, Kai; Hu, Dandan; Xie, Youtao; Huang, Liping; Zheng, Xuebin
2018-02-01
Biomedical coatings for orthopedic implants should facilitate osseointegration and mitigate implant-induced inflammatory reactions. In our study, Ca-Si coatings with Sr-containing nanowire-like structures (NW-Sr-CS) were achieved via hydrothermal treatment. In order to identify the effect of nanowire-like topography and Sr dopant on the biological properties of Ca-Si-based coatings, the original Ca-Si coating, Ca-Si coatings modified with nanoplate (NP-CS) and similar nanowire-like structure (NW-CS) were fabricated as the control. Surface morphology, phase composition, surface area, zeta potential and ion release of these coatings were characterized. The in vitro osteogenic activities and immunomodulatory properties were evaluated with bone marrow stromal cells (BMSCs) and RAW 264.7 cells, a mouse macrophage cell line. Compared with the CS and NP-CS coatings, the NW-CS coating possessed a larger surface area and pore volume, beneficial protein adsorption, up-regulated the expression levels of integrin β1, Vinculin and focal adhesion kinase and promoted cell spreading. Furthermore, the NW-CS coating significantly enhanced the osteogenic differentiation and mineralization as indicated by the up-regulation of ALP activity, mineralized nodule formation and osteoblastogenesis-related gene expression. With the introduction of Sr, the NW-Sr-CS coatings exerted a greater effect on the BMSC proliferation rate, calcium sensitive receptor gene expression as well as PKC and ERK1/2 phosphorylation. In addition, the Sr-doped coatings significantly up-regulated the ratio of OPG/RANKL in the BMSCs. The NW-Sr-CS coatings could modulate the polarization of macrophages towards the wound-healing M2 phenotype, reduce the mRNA expression levels of pro-inflammatory cytokines (TNF-α, IL-1β, IL-6) and enhance anti-inflammatory cytokines (IL-1ra, IL-10). The Sr-doped nanowire modification may be a valuable approach to enhance osteogenic activities and reduce inflammatory reactions.
Nanoscale patterning of Si surface using SPM scratching
NASA Astrophysics Data System (ADS)
Ogino, T.; Nishimura, S.; Shirakashi, J.
2008-03-01
Nanolithography of Si surface using scanning probe microscopy (SPM) scratching with a diamond-coated tip was systematically investigated at a low force regime below 9 μN. The groove patterns with controlled width and depth could be achieved by adjusting the applied force, scan direction and the number of scan cycles. There was no effect of scan speed on the groove size. The minimum groove width of 10 nm was obtained on Si surfaces. Furthermore, more complex nanostructures such as line and space patterns of 30 nm pith and dot arrays of 2.6×1010 cm-2 density were realized. SPM scratching with a diamond-coated tip allows nanoscale patterning of Si surfaces to be performed simply.
MANUAL: POLLUTION PREVENTION IN THE PAINTS AND COATINGS INDUSTRY
The paints and coatings industry represents a significant source of multimedia pollution through the wide use of solvent-based process materials and the extensive amounts of wastewater generated by the operations. This manual presents recommended practices for minimizing the gene...
The use of phage display in neurobiology.
Bradbury, Andrew R M
2010-04-01
Phage display has been extensively used to study protein-protein interactions, receptor- and antibody-binding sites, and immune responses, to modify protein properties, and to select antibodies against a wide range of different antigens. In the format most often used, a polypeptide is displayed on the surface of a filamentous phage by genetic fusion to one of the coat proteins, creating a chimeric coat protein, and coupling phenotype (the protein) to genotype (the gene within). As the gene encoding the chimeric coat protein is packaged within the phage, selection of the phage on the basis of the binding properties of the polypeptide displayed on the surface simultaneously results in the isolation of the gene encoding the polypeptide. This unit describes the background to the technique, and illustrates how it has been applied to a number of different problems, each of which has its neurobiological counterparts. Although this overview concentrates on the use of filamentous phage, which is the most popular platform, other systems are also described. (c) 2010 by John Wiley & Sons, Inc.
Defect tolerant transmission lithography mask
Vernon, Stephen P.
2000-01-01
A transmission lithography mask that utilizes a transparent substrate or a partially transparent membrane as the active region of the mask. A reflective single layer or multilayer coating is deposited on the membrane surface facing the illumination system. The coating is selectively patterned (removed) to form transmissive (bright) regions. Structural imperfections and defects in the coating have negligible effect on the aerial image of the mask master pattern since the coating is used to reflect radiation out of the entrance pupil of the imaging system. Similarly, structural imperfections in the clear regions of the membrane have little influence on the amplitude or phase of the transmitted electromagnetic fields. Since the mask "discards," rather than absorbs, unwanted radiation, it has reduced optical absorption and reduced thermal loading as compared to conventional designs. For EUV applications, the mask circumvents the phase defect problem, and is independent of the thermal load during exposure.
NASA Astrophysics Data System (ADS)
Hu, Zengrong; Li, Yue; Fan, Xueliang; Chen, Feng; Xu, Jiale
2018-04-01
Single layer grapheme oxide Nano sheets and Nano titanium powder were dispersed in deionized water by ultrasonic dispersion. Then the mixed solution was pre-coating on AISI4140 substrate. Using laser sintering process to fabricated grapheme oxide and Ti composite coating. Microstructures and composition of the composite coating was studied by Scanning Electron Microscopy (SEM), x-ray diffract meter (XRD) and Raman spectroscopy. Raman spectrum, XRD pattern and SEM results proved that grapheme oxide sheets were dispersed in the composite coating. The composite coating had much higher average Vickers hardness values than that of pure Ti coating. The tribological performance of the composite coatings became better while the suitable GO content was selected. For the 2.5wt. % GO content coating, the friction coefficient was reduced to near 0.1.
Basnet, Ram Kumar; Moreno-Pachon, Natalia; Lin, Ke; Bucher, Johan; Visser, Richard G F; Maliepaard, Chris; Bonnema, Guusje
2013-12-01
Brassica seeds are important as basic units of plant growth and sources of vegetable oil. Seed development is regulated by many dynamic metabolic processes controlled by complex networks of spatially and temporally expressed genes. We conducted a global microarray gene co-expression analysis by measuring transcript abundance of developing seeds from two diverse B. rapa morphotypes: a pak choi (leafy-type) and a yellow sarson (oil-type), and two of their doubled haploid (DH) progenies, (1) to study the timing of metabolic processes in developing seeds, (2) to explore the major transcriptional differences in developing seeds of the two morphotypes, and (3) to identify the optimum stage for a genetical genomics study in B. rapa seed. Seed developmental stages were similar in developing seeds of pak choi and yellow sarson of B. rapa; however, the colour of embryo and seed coat differed among these two morphotypes. In this study, most transcriptional changes occurred between 25 and 35 DAP, which shows that the timing of seed developmental processes in B. rapa is at later developmental stages than in the related species B. napus. Using a Weighted Gene Co-expression Network Analysis (WGCNA), we identified 47 "gene modules", of which 27 showed a significant association with temporal and/or genotypic variation. An additional hierarchical cluster analysis identified broad spectra of gene expression patterns during seed development. The predominant variation in gene expression was according to developmental stages rather than morphotype differences. Since lipids are the major storage compounds of Brassica seeds, we investigated in more detail the regulation of lipid metabolism. Four co-regulated gene clusters were identified with 17 putative cis-regulatory elements predicted in their 1000 bp upstream region, either specific or common to different lipid metabolic pathways. This is the first study of genome-wide profiling of transcript abundance during seed development in B. rapa. The identification of key physiological events, major expression patterns, and putative cis-regulatory elements provides useful information to construct gene regulatory networks in B. rapa developing seeds and provides a starting point for a genetical genomics study of seed quality traits.
NASA Technical Reports Server (NTRS)
Burkholder, R. J.; Chuang, C. W.; Pathak, P. H.
1987-01-01
The EM backscatter from a two-dimensional S-shaped inlet cavity is analyzed using three different techniques, namely a hybrid combination of asymptotic high frequency and modal methods, an integral equation method, and the geometrical optics ray method, respectively. This inlet has a thin absorber coating on its perfectly conducting inner walls and the planar interior termination is made perfectly conducting. The effect of the absorber on the inner wall is treated via a perturbation scheme in the hybrid approach where it is assumed that the loss is sufficiently small for the method to be valid. The results are compared with the backscatter from a straight inlet cavity to evaluate the effect of offsetting the termination in the S-bend configuration such that it is not visible from the open end of the inlet. The envelope of the backscatter pattern for the straight inlet is always seen to peak around the forward axis due to the large return from the directly visible termination, and the pattern envelope tapers off away from the forward axis. Offsetting the termination causes the envelope of the backscatter pattern to flatten out, thereby reducing the return near the forward axis by several dB. The absorber coating reduces the pattern level of the straight inlet in directions away from the forward axis but has little effect on the peak near the axis; furthermore, the absorber coating is seen to consistently reduce the backscatter from the S-bend inlet for almost all incidence angles. The hybrid method gives excellent agreement with experimental data and with the integral equation solution, whereas, the geometrical optics ray tracing method is able to generally predict the average of the bachscatter pattern but not the pattern details.
Long-Term Evolution of the Luteoviridae: Time Scale and Mode of Virus Speciation▿ †
Pagán, Israel; Holmes, Edward C.
2010-01-01
Despite their importance as agents of emerging disease, the time scale and evolutionary processes that shape the appearance of new viral species are largely unknown. To address these issues, we analyzed intra- and interspecific evolutionary processes in the Luteoviridae family of plant RNA viruses. Using the coat protein gene of 12 members of the family, we determined their phylogenetic relationships, rates of nucleotide substitution, times to common ancestry, and patterns of speciation. An associated multigene analysis enabled us to infer the nature of selection pressures and the genomic distribution of recombination events. Although rates of evolutionary change and selection pressures varied among genes and species and were lower in some overlapping gene regions, all fell within the range of those seen in animal RNA viruses. Recombination breakpoints were commonly observed at gene boundaries but less so within genes. Our molecular clock analysis suggested that the origin of the currently circulating Luteoviridae species occurred within the last 4 millennia, with intraspecific genetic diversity arising within the last few hundred years. Speciation within the Luteoviridae may therefore be associated with the expansion of agricultural systems. Finally, our phylogenetic analysis suggested that viral speciation events tended to occur within the same plant host species and country of origin, as expected if speciation is largely sympatric, rather than allopatric, in nature. PMID:20375155
Leisner, Courtney P; Yendrek, Craig R; Ainsworth, Elizabeth A
2017-12-12
Understanding how intensification of abiotic stress due to global climate change affects crop yields is important for continued agricultural productivity. Coupling genomic technologies with physiological crop responses in a dynamic field environment is an effective approach to dissect the mechanisms underpinning crop responses to abiotic stress. Soybean (Glycine max L. Merr. cv. Pioneer 93B15) was grown in natural production environments with projected changes to environmental conditions predicted for the end of the century, including decreased precipitation, increased tropospheric ozone concentrations ([O 3 ]), or increased temperature. All three environmental stresses significantly decreased leaf-level photosynthesis and stomatal conductance, leading to significant losses in seed yield. This was driven by a significant decrease in the number of pods per node for all abiotic stress treatments. To understand the underlying transcriptomic response involved in the yield response to environmental stress, RNA-Sequencing analysis was performed on the soybean seed coat, a tissue that plays an essential role in regulating carbon and nitrogen transport to developing seeds. Gene expression analysis revealed 49, 148 and 1,576 differentially expressed genes in the soybean seed coat in response to drought, elevated [O 3 ] and elevated temperature, respectively. Elevated [O 3 ] and drought did not elicit substantive transcriptional changes in the soybean seed coat. However, this may be due to the timing of sampling and does not preclude impacts of those stresses on different tissues or different stages in seed coat development. Expression of genes involved in DNA replication and metabolic processes were enriched in the seed coat under high temperate stress, suggesting that the timing of events that are important for cell division and proper seed development were altered in a stressful growth environment.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Oswald, S.G.; Van Nostrand, D.; Savory, C.G.
1990-03-01
Although few studies address the use of three-phase bone scanning (TPBS) and indium-111-labeled white blood cell scintigraphy ({sup 111}In-WBC) in hip arthroplasty utilizing a porous-coated prosthesis, the literature suggests that scintigraphic patterns in the uncomplicated patient may differ from that seen with the cemented prosthesis. In an attempt to determine the scintigraphic natural history, 25 uncomplicated porous-coated hip arthroplasties in 21 patients were prospectively studied with serial TPBS and {sup 111I}n-WBC at approximately 7 days, and 3, 6, 12, 18, and 24 mo postoperatively. This report deals with findings related to the acetabulum. All 25 prostheses (144 of 144 scans)more » demonstrated increased uptake on the bone-phase images. Although this activity decreased with time, 76% had persistent uptake at 24 mo. Twenty-three of 25 prostheses (126 of 140 scans) showed increased uptake on {sup 111}In-WBC scintigraphy, invariably decreasing with time, but with 37% having significant uptake at 24 mo. Scintigraphic patterns in the uncomplicated porous-coated hip arthroplasty patient appear to differ from patterns described in cemented prostheses.« less
Surface patterning of soft polymer film-coated cylinders via an electric field.
Li, Bo; Li, Yue; Xu, Guang-Kui; Feng, Xi-Qiao
2009-11-04
Using the linear stability analysis method, we investigate the surface wrinkling of a thin polymer coating on a cylinder in an externally applied electric field. It is demonstrated that energy competition between surface energy, van der Waals interactive potential energy and electrostatic interaction energy may lead to ordered patterns on the film surface. The analytical solutions are derived for the critical conditions of both longitudinal and circumferential instabilities. The wavelengths of the generated surface patterns can be mediated by changing the magnitude of the electric field. Our analysis shows that the surface morphology is sensitive to the curvature radius of the fiber, especially in the micrometer and nanometer length scales. Furthermore, we suggest a potential approach for fabricating hierarchical patterns on curved surfaces.
The Genetic Inheritance of the Blue-eyed White Phenotype in Alpacas (Vicugna pacos)
Johnson, Warren E.; Appleton, Belinda R.
2014-01-01
White-spotting patterns in mammals can be caused by mutations in the gene KIT, whose protein is necessary for the normal migration and survival of melanocytes from the neural crest. The alpaca (Vicugna pacos) blue-eyed white (BEW) phenotype is characterized by 2 blue eyes and a solid white coat over the whole body. Breeders hypothesize that the BEW phenotype in alpacas is caused by the combination of the gene causing gray fleece and a white-spotting gene. We performed an association study using KIT flanking and intragenic markers with 40 unrelated alpacas, of which 17 were BEW. Two microsatellite alleles at KIT-related markers were significantly associated (P < 0.0001) with the BEW phenotype (bew1 and bew2). In a larger cohort of 171 related individuals, we identify an abundance of an allele (bew1) in gray animals and the occurrence of bew2 homozygotes that are solid white with pigmented eyes. Association tests accounting for population structure and familial relatedness are consistent with a proposed model where these alleles are in linkage disequilibrium with a mutation or mutations that contribute to the BEW phenotype and to individual differences in fleece color. PMID:23144493
Herzog, Etienne; Guerra-Peraza, Orlene; Hohn, Thomas
2000-01-01
Rice tungro bacilliform virus (RTBV) is a plant pararetrovirus whose DNA genome contains four genes encoding three proteins and a large polyprotein. The function of most of the viral proteins is still unknown. To investigate the role of the gene II product (P2), we searched for interactions between this protein and other RTBV proteins. P2 was shown to interact with the coat protein (CP) domain of the viral gene III polyprotein (P3) both in the yeast two-hybrid system and in vitro. Domains involved in the P2-CP association have been identified and mapped on both proteins. To determine the importance of this interaction for viral multiplication, the infectivity of RTBV gene II mutants was investigated by agroinoculation of rice plants. The results showed that virus viability correlates with the ability of P2 to interact with the CP domain of P3. This study suggests that P2 could participate in RTBV capsid assembly. PMID:10666237
Formation of ordered microphase-separated pattern during spin coating of ABC triblock copolymer.
Huang, Weihuan; Luo, Chunxia; Zhang, Jilin; Han, Yanchun
2007-03-14
In this paper, the authors have systematically studied the microphase separation and crystallization during spin coating of an ABC triblock copolymer, polystyrene-b-poly(2-vinylpyridine)-b-poly(ethylene oxide) (PS-b-P2VP-b-PEO). The microphase separation of PS-b-P2VP-b-PEO and the crystallization of PEO blocks can be modulated by the types of the solvent and the substrate, the spinning speed, and the copolymer concentration. Ordered microphase-separated pattern, where PEO and P2VP blocks adsorbed to the substrate and PS blocks protrusions formed hexagonal dots above the P2VP domains, can only be obtained when PS-b-P2VP-b-PEO is dissolved in N,N-dimethylformamide and the films are spin coated onto the polar substrate, silicon wafers or mica. The mechanism of the formation of regular pattern by microphase separation is found to be mainly related to the inducement of the substrate (middle block P2VP wetting the polar substrate), the quick vanishment of the solvent during the early stage of the spin coating, and the slow evaporation of the remaining solvent during the subsequent stage. On the other hand, the probability of the crystallization of PEO blocks during spin coating decreases with the reduced film thickness. When the film thickness reaches a certain value (3.0 nm), the extensive crystallization of PEO is effectively prohibited and ordered microphase-separated pattern over large areas can be routinely prepared. When the film thickness exceeds another definite value (12.0 nm), the crystallization of PEO dominates the surface morphology. For films with thickness between these two values, microphase separation and crystallization can simultaneously occur.
Nishio, Shunsuke; Kohno, Yoshinori; Iwata, Yuki; Arai, Mayumi; Okumura, Hiroki; Oshima, Kenzi; Nadano, Daita; Matsuda, Tsukasa
2014-11-01
Vertebrate eggs are surrounded by an egg coat, which is a specific extracellular egg matrix consisting of several glycoproteins with a conserved zona pellucida (ZP) domain. Two mammalian egg coat subunits, ZP2 and ZP3, have been suggested to act as sperm receptors. In bird eggs, however, ZP2 has never been identified in the egg coat of mature oocytes and ovulated eggs. Here we report that chicken ZP2 is expressed in immature small follicles and remains as an egg-coat component locally in the germinal disc region of mature eggs. RT-PCR analysis indicated marked expression of the ZP2 and ZP4 genes in the granulosa cells of immature white follicles, whereas the ZP3 and ZPD genes showed marked expression in the cells of maturing yellow follicles. ZP2 was identified in the egg coat isolated from immature follicles as a heavily N-glycosylated glycoprotein of ∼200 kDa, which was enzymatically converted to a 70-kDa deglycosylated form. Immunoblotting and immunohistological analyses showed that ZP2 was localized around the germinal disc region of mature follicles. ZP2 was accumulated in the egg coat of immature white follicles at the earlier stages of oocyte development and became a minor component in the egg coat of maturing yellow follicles, except for the germinal disc region. Localization of ZP2 in the germinal disc region of mature eggs, where sperm bind to the egg coat at high density, suggests some role for ZP2 in the preferential binding and penetration of sperm in the germinal disc region of bird eggs. © 2014 by the Society for the Study of Reproduction, Inc.
Zhang, Tingting; Stilwell, Jackie L; Gerion, Daniele; Ding, Lianghao; Elboudwarej, Omeed; Cooke, Patrick A; Gray, Joe W; Alivisatos, A Paul; Chen, Fanqing Frank
2006-04-01
Quantum dots (Qdots) are now used extensively for labeling in biomedical research, and this use is predicted to grow because of their many advantages over alternative labeling methods. Uncoated Qdots made of core/shell CdSe/ZnS are toxic to cells because of the release of Cd2+ ions into the cellular environment. This problem has been partially overcome by coating Qdots with polymers, poly(ethylene glycol) (PEG), or other inert molecules. The most promising coating to date, for reducing toxicity, appears to be PEG. When PEG-coated silanized Qdots (PEG-silane-Qdots) are used to treat cells, toxicity is not observed, even at dosages above 10-20 nM, a concentration inducing death when cells are treated with polymer or mercaptoacid coated Qdots. Because of the importance of Qdots in current and future biomedical and clinical applications, we believe it is essential to more completely understand and verify this negative global response from cells treated with PEG-silane-Qdots. Consequently, we examined the molecular and cellular response of cells treated with two different dosages of PEG-silane-Qdots. Human fibroblasts were exposed to 8 and 80 nM of these Qdots, and both phenotypic as well as whole genome expression measurements were made. PEG-silane-Qdots did not induce any statistically significant cell cycle changes and minimal apoptosis/necrosis in lung fibroblasts (IMR-90) as measured by high content image analysis, regardless of the treatment dosage. A slight increase in apoptosis/necrosis was observed in treated human skin fibroblasts (HSF-42) at both the low and the high dosages. We performed genome-wide expression array analysis of HSF-42 exposed to doses 8 and 80 nM to link the global cell response to a molecular and genetic phenotype. We used a gene array containing approximately 22,000 total probe sets, containing 18,400 probe sets from known genes. Only approximately 50 genes (approximately 0.2% of all the genes tested) exhibited a statistically significant change in expression level of greater than 2-fold. Genes activated in treated cells included those involved in carbohydrate binding, intracellular vesicle formation, and cellular response to stress. Conversely, PEG-silane-Qdots induce a down-regulation of genes involved in controlling the M-phase progression of mitosis, spindle formation, and cytokinesis. Promoter analysis of these results reveals that expression changes may be attributed to the down-regulation of FOXM and BHLB2 transcription factors. Remarkably, PEG-silane-Qdots, unlike carbon nanotubes, do not activate genes indicative of a strong immune and inflammatory response or heavy-metal-related toxicity. The experimental evidence shows that CdSe/ZnS Qdots, if appropriately protected, induce negligible toxicity to the model cell system studied here, even when exposed to high dosages. This study indicates that PEG-coated silanized Qdots pose minimal impact to cells and are a very promising alternative to uncoated Qdots.
Protein patterning in polycarbonate microfluidic channels
NASA Astrophysics Data System (ADS)
Thomson, David A.; Hayes, Jason P.; Thissen, Helmut
2004-03-01
In this work protein patterning has been achieved within a polycarbonate microfluidic device. Channel structures were first coated with plasma polymerized allylamine (ALAPP) followed by the "cloud point" deposition of polyethylene oxide (PEO), a protein repellent molecule. Excimer laser micromachining was used to pattern the PEO to control protein localization. Subsequent removal of a sacrificial layer of polycarbonate resulted in the patterned polymer coating only in the channels of a simple fluidic device. Following a final diffusion bonding fabrication step the devices were filled with a buffer containing Streptavidin conjugated with fluorescein, and visualized under a confocal fluorescent microscope. This confirmed that protein adhesion occurred only in laser patterned areas. The ability to control protein adhesion in microfludic channels leads to the possibility of generating arrays of proteins or cells within polymer microfludics for cheap automated biosensors and synthesis systems.
A new gene that controls seed coat wrinkling in soybean
USDA-ARS?s Scientific Manuscript database
Seed coat wrinkling is a major factor affecting the germinability of soybean [Glycine max (L.) Merr.] seed produced in high-temperature environments, such as in the early soybean production system (ESPS) of the midsouthern United States. Exposure of seed to high temperatures, coupled with alternatin...
Genetics Home Reference: Coats plus syndrome
... of telomeres. However, it is unclear how CTC1 gene mutations impact telomere structure and function. Some studies have found that people with CTC1 gene mutations have abnormally short telomeres, while other studies have ...
Fe₃O₄ Nanoparticles in Targeted Drug/Gene Delivery Systems.
Shen, Lazhen; Li, Bei; Qiao, Yongsheng
2018-02-23
Fe₃O₄ nanoparticles (NPs), the most traditional magnetic nanoparticles, have received a great deal of attention in the biomedical field, especially for targeted drug/gene delivery systems, due to their outstanding magnetism, biocompatibility, lower toxicity, biodegradability, and other features. Naked Fe₃O₄ NPs are easy to aggregate and oxidize, and thus are often made with various coatings to realize superior properties for targeted drug/gene delivery. In this review, we first list the three commonly utilized synthesis methods of Fe₃O₄ NPs, and their advantages and disadvantages. In the second part, we describe coating materials that exhibit noticeable features that allow functionalization of Fe₃O₄ NPs and summarize their methods of drug targeting/gene delivery. Then our efforts will be devoted to the research status and progress of several different functionalized Fe₃O₄ NP delivery systems loaded with chemotherapeutic agents, and we present targeted gene transitive carriers in detail. In the following section, we illuminate the most effective treatment systems of the combined drug and gene therapy. Finally, we propose opportunities and challenges of the clinical transformation of Fe₃O₄ NPs targeting drug/gene delivery systems.
NASA Astrophysics Data System (ADS)
Shim, Hyun-Woo; Lee, Ji-Hye; Choi, Chang-Hyoung; Song, Hwan-Moon; Kim, Bo-Yeol; Kim, Dong-Pyo; Lee, Chang-Soo
2007-12-01
The patterning of biomolecules in well-defined microstructures is critical issue for the development of biosensors and biochips. However, the fabrication of microstructures with well-ordered and spatially discrete forms to provide the patterned surface for the immobilization of biomolecules is difficult because of the lack of distinct physical and chemical barriers separating patterns. This study present rapid biomolecule patterning using micromolding in capillaries (MIMIC), soft-lithographic fabrication of PEG microstructures for prevention of nonspecific binding as a biological barrier, and self assembled polymeric thin film for efficient immobilization of proteins or cells. For the proof of concept, protein (FITC-BSA), bacteria (E.coli BL21-pET23b-GFP) were used for biomolecules patterning on polyelectrolyte coated surface within PEG microstructures. The novel approach of MIMIC combined with LbL coating provides a general platform for patterning a broad range of materials because it can be easily applied to various substrates such as glass, silicon, silicon dioxide, and polymers.
Biological pattern formation: from basic mechanisms to complex structures
NASA Astrophysics Data System (ADS)
Koch, A. J.; Meinhardt, H.
1994-10-01
The reliable development of highly complex organisms is an intriguing and fascinating problem. The genetic material is, as a rule, the same in each cell of an organism. How then do cells, under the influence of their common genes, produce spatial patterns? Simple models are discussed that describe the generation of patterns out of an initially nearly homogeneous state. They are based on nonlinear interactions of at least two chemicals and on their diffusion. The concepts of local autocatalysis and of long-range inhibition play a fundamental role. Numerical simulations show that the models account for many basic biological observations such as the regeneration of a pattern after excision of tissue or the production of regular (or nearly regular) arrays of organs during (or after) completion of growth. Very complex patterns can be generated in a reproducible way by hierarchical coupling of several such elementary reactions. Applications to animal coats and to the generation of polygonally shaped patterns are provided. It is further shown how to generate a strictly periodic pattern of units that themselves exhibit a complex and polar fine structure. This is illustrated by two examples: the assembly of photoreceptor cells in the eye of Drosophila and the positioning of leaves and axillary buds in a growing shoot. In both cases, the substructures have to achieve an internal polarity under the influence of some primary pattern-forming system existing in the fly's eye or in the plant. The fact that similar models can describe essential steps in organisms as distantly related as animals and plants suggests that they reveal some universal mechanisms.
Easy-to-fabricate thin-film coating on PDMS substrate with super hydrophilicity and stability.
Sun, Lijun; Luo, Yong; Gao, Zhigang; Zhao, Weijie; Lin, Bingcheng
2015-03-01
With the fast expansion of microfluidic applications, stable, and easy-to-fabricate PDMS surface coating with super hydrophilicity is highly desirable. In this study, we introduce a new kind of copolymer-based, single-layer thin-film coating for PDMS. The coating can exist in air at room temperature for at least 6 months without any noticeable deterioration in the super hydrophilicity (water contact angle ∼7°), resistance of protein adsorption, or inhibition of the EOF. In addition, this coating enables arbitrary patterning of cells on planar surfaces. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Role of Lipid Metabolism in Plant Pollen Exine Development.
Zhang, Dabing; Shi, Jianxin; Yang, Xijia
2016-01-01
Pollen plays important roles in the life cycle of angiosperms plants. It acts as not only a biological protector of male sperms but also a communicator between the male and the female reproductive organs, facilitating pollination and fertilization. Pollen is produced within the anther, and covered by the specialized outer envelope, pollen wall. Although the morphology of pollen varies among different plant species, the pollen wall is mainly comprised of three layers: the pollen coat, the outer exine layer, and the inner intine layer. Except the intine layer, the other two layers are basically of lipidic nature. Particularly, the outer pollen wall layer, the exine, is a highly resistant biopolymer of phenylpropanoid and lipidic monomers covalently coupled by ether and ester linkages. The precise molecular mechanisms underlying pollen coat formation and exine patterning remain largely elusive. Herein, we summarize the current genetic, phenotypic and biochemical studies regarding to the pollen exine development and underlying molecular regulatory mechanisms mainly obtained from monocot rice (Oryza sativa) and dicot Arabidopsis thaliana, aiming to extend our understandings of plant male reproductive biology. Genes, enzymes/proteins and regulatory factors that appear to play conserved and diversified roles in lipid biosynthesis, transportation and modification during pollen exine formation, were highlighted.
Gao, Wei; Vander Sande, John B.
1998-01-01
A method is provided for fabrication of superconducting oxides and superconducting oxide composites and for joining superconductors to other materials. A coating of a molten alloy containing the metallic elements of the oxide is applied to a substrate surface and oxidized to form the superconducting oxide. A material can be contacted to the molten alloy which is subsequently oxidized joining the material to the resulting superconducting oxide coating. Substrates of varied composition and shape can be coated or joined by this method.
Gao, W.; Vander Sande, J.B.
1998-07-28
A method is provided for fabrication of superconducting oxides and superconducting oxide composites and for joining superconductors to other materials. A coating of a molten alloy containing the metallic elements of the oxide is applied to a substrate surface and oxidized to form the superconducting oxide. A material can be contacted to the molten alloy which is subsequently oxidized joining the material to the resulting superconducting oxide coating. Substrates of varied composition and shape can be coated or joined by this method. 5 figs.
Distinctive glial and neuronal interfacing on nanocrystalline diamond.
Bendali, Amel; Agnès, Charles; Meffert, Simone; Forster, Valérie; Bongrain, Alexandre; Arnault, Jean-Charles; Sahel, José-Alain; Offenhäusser, Andreas; Bergonzo, Philippe; Picaud, Serge
2014-01-01
Direct electrode/neuron interfacing is a key challenge to achieve high resolution of neuronal stimulation required for visual prostheses. Neuronal interfacing on biomaterials commonly requires the presence of glial cells and/or protein coating. Nanocrystalline diamond is a highly mechanically stable biomaterial with a remarkably large potential window for the electrical stimulation of tissues. Using adult retinal cell cultures from rats, we found that glial cells and retinal neurons grew equally well on glass and nanocrystalline diamond. The use of a protein coating increased cell survival, particularly for glial cells. However, bipolar neurons appeared to grow even in direct contact with bare diamond. We investigated whether the presence of glial cells contributed to this direct neuron/diamond interface, by using purified adult retinal ganglion cells to seed diamond and glass surfaces with and without protein coatings. Surprisingly, these fully differentiated spiking neurons survived better on nanocrystalline diamond without any protein coating. This greater survival was indicated by larger cell numbers and the presence of longer neurites. When a protein pattern was drawn on diamond, neurons did not grow preferentially on the coated area, by contrast to their behavior on a patterned glass. This study highlights the interesting biocompatibility properties of nanocrystalline diamond, allowing direct neuronal interfacing, whereas a protein coating was required for glial cell growth.
Distinctive Glial and Neuronal Interfacing on Nanocrystalline Diamond
Bendali, Amel; Agnès, Charles; Meffert, Simone; Forster, Valérie; Bongrain, Alexandre; Arnault, Jean-Charles; Sahel, José-Alain; Offenhäusser, Andreas; Bergonzo, Philippe; Picaud, Serge
2014-01-01
Direct electrode/neuron interfacing is a key challenge to achieve high resolution of neuronal stimulation required for visual prostheses. Neuronal interfacing on biomaterials commonly requires the presence of glial cells and/or protein coating. Nanocrystalline diamond is a highly mechanically stable biomaterial with a remarkably large potential window for the electrical stimulation of tissues. Using adult retinal cell cultures from rats, we found that glial cells and retinal neurons grew equally well on glass and nanocrystalline diamond. The use of a protein coating increased cell survival, particularly for glial cells. However, bipolar neurons appeared to grow even in direct contact with bare diamond. We investigated whether the presence of glial cells contributed to this direct neuron/diamond interface, by using purified adult retinal ganglion cells to seed diamond and glass surfaces with and without protein coatings. Surprisingly, these fully differentiated spiking neurons survived better on nanocrystalline diamond without any protein coating. This greater survival was indicated by larger cell numbers and the presence of longer neurites. When a protein pattern was drawn on diamond, neurons did not grow preferentially on the coated area, by contrast to their behavior on a patterned glass. This study highlights the interesting biocompatibility properties of nanocrystalline diamond, allowing direct neuronal interfacing, whereas a protein coating was required for glial cell growth. PMID:24664111
Arnfinnsdottir, Nina Bjørk; Ottesen, Vegar; Lale, Rahmi; Sletmoen, Marit
2015-01-01
In this paper we demonstrate a procedure for preparing bacterial arrays that is fast, easy, and applicable in a standard molecular biology laboratory. Microcontact printing is used to deposit chemicals promoting bacterial adherence in predefined positions on glass surfaces coated with polymers known for their resistance to bacterial adhesion. Highly ordered arrays of immobilized bacteria were obtained using microcontact printed islands of polydopamine (PD) on glass surfaces coated with the antiadhesive polymer polyethylene glycol (PEG). On such PEG-coated glass surfaces, bacteria were attached to 97 to 100% of the PD islands, 21 to 62% of which were occupied by a single bacterium. A viability test revealed that 99% of the bacteria were alive following immobilization onto patterned surfaces. Time series imaging of bacteria on such arrays revealed that the attached bacteria both divided and expressed green fluorescent protein, both of which indicates that this method of patterning of bacteria is a suitable method for single-cell analysis.
Wei, Mingjie; Wang, Yong
2015-01-01
Patterning metallic nanoparticles on substrate surfaces is important in a number of applications. However, it remains challenging to fabricate such patterned nanoparticles with easily controlled structural parameters, including particle sizes and densities, from simple methods. We report on a new route to directly pattern pre-formed gold nanoparticles with different diameters on block copolymer micellar monolayers coated on silicon substrates. Due to the synergetic effect of complexation and electrostatic interactions between the micellar cores and the gold particles, incubating the copolymer-coated silicon in a gold nanoparticles suspension leads to a monolayer of gold particles attached on the coated silicon. The intermediate micellar film was then removed using oxygen plasma treatment, allowing the direct contact of the gold particles with the Si substrate. We further demonstrate that the gold nanoparticles can serve as catalysts for the localized etching of the silicon substrate, resulting in nanoporous Si with a top layer of straight pores. PMID:28793407
2013-01-01
Background Inhaled nanoparticles have been reported in some instances to translocate from the nostril to the olfactory bulb in exposed rats. In close proximity to the olfactory bulb is the olfactory mucosa, within which resides a niche of multipotent cells. Cells isolated from this area may provide a relevant in vitro system to investigate potential effects of workplace exposure to inhaled zinc oxide nanoparticles. Methods Four types of commercially-available zinc oxide (ZnO) nanoparticles, two coated and two uncoated, were examined for their effects on primary human cells cultured from the olfactory mucosa. Human olfactory neurosphere-derived (hONS) cells from healthy adult donors were analyzed for modulation of cytokine levels, activation of intracellular signalling pathways, changes in gene-expression patterns across the whole genome, and compromised cellular function over a 24 h period following exposure to the nanoparticles suspended in cell culture medium. Results ZnO nanoparticle toxicity in hONS cells was mediated through a battery of mechanisms largely related to cell stress, inflammatory response and apoptosis, but not activation of mechanisms that repair damaged DNA. Surface coatings on the ZnO nanoparticles mitigated these cellular responses to varying degrees. Conclusions The results indicate that care should be taken in the workplace to minimize generation of, and exposure to, aerosols of uncoated ZnO nanoparticles, given the adverse responses reported here using multipotent cells derived from the olfactory mucosa. PMID:24144420
Identification of a single gene for seed coat impermeability in soybean PI 594619
USDA-ARS?s Scientific Manuscript database
High temperatures during seed fill increase the occurrence of soybeans with impermeable seed coat, which is associated with non-uniform and delayed germination and emergence. This has become an issue in soybean production areas with excessively high-temperature environments. The objectives of the pr...
Martin, Lauren; Damaso, Natalie; Mills, DeEtta
2016-10-01
Molecular methods for the detection of mammalian coat color phenotypes have expanded greatly within the past decade. Many phenotypes are associated with a single nucleotide polymorphism mutation in the genetic sequence. Traditionally, these mutations are detected through sequencing, hybridization assays or mini-sequencing. However, these techniques can be expensive and tedious. Previously, CE-SSCP using the F-108 polymer was able to distinguish SNPs for the melanocortin-1 receptor (mc1r) coat color gene in horses (Equus caballus) that differed by one nucleotide substitution. The objective of this study was to expand the detection of coat color SNPs in horses. The genes for the solute carrier family member 2 (slc45a2/matp), type III receptor protein-tyrosine kinase (kit) and mc1r genes using CE-SSCP and F-108 polymer were compared to mini-sequencing with the SNaPshot TM kit. The F-108 polymer reproducibly resolved homozygous and heterozygous individuals for the mc1r and kit markers, but was unable to resolve heterozygous individuals for slc45a2 at 38ºC. The need for temperatures <15ºC, the SNP position being close to the 5'-end, and conformational structures/free energy with similar values resulted in the inability to resolve the secondary structures. Despite this limitation, the CE-SSCP method could be used to provide a rapid phenotypic description for equine forensic investigations. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
NASA Astrophysics Data System (ADS)
Konishi, Satoshi; Nakagami, Chise; Kobayashi, Taizo; Tonomura, Wataru; Kaizuma, Yoshihiro
2015-04-01
In this work, a lift-off process with bi-layer photoresist patterns was applied to the formation of hydrophobic/hydrophilic micropatterns on practical polymer substrates used in healthcare diagnostic commercial products. The bi-layer photoresist patterns with undercut structures made it possible to peel the conformal-coated silicon oxide (SiOx) films from substrates. SiOx and silicon carbide (SiCx) layers were deposited by pulsed plasma chemical vapor deposition (PPCVD) method which can form roughened surfaces to enhance hydrophilicity of SiOx and hydrophobicity of SiCx. Microfluidic applications using hydrophobic/hydrophilic patterns were also demonstrated on low-cost substrates such as poly(ethylene terephthalate) (PET) and paper films.
The effect of collagen coating on titanium with nanotopography on in vitro osteogenesis.
Costa, Daniel G; Ferraz, Emanuela P; Abuna, Rodrigo P F; de Oliveira, Paulo T; Morra, Marco; Beloti, Marcio M; Rosa, Adalberto L
2017-10-01
Several studies have shown the positive effects of Ti either with nanotopography or coated with collagen on osteoblast differentiation. Thus, we hypothesized that the association of nanotopography with collagen may increase the in vitro osteogenesis on Ti surface. Ti discs with nanotopography with or without collagen coating were characterized by scanning electron microscopy and atomic force microscopy. Rat calvaria-derived osteoblastic cells were cultured on both Ti surfaces for up to 14 days and the following parameters were evaluated: cell proliferation, alkaline phosphatase (ALP) activity, extracellular matrix mineralization, protein expression of bone sialoprotein (BSP) and osteopontin (OPN), and gene expression of collagen type 1a (Coll1a), runt-related transcription factor 2 (Runx2), osterix (OSX), osteocalcin (OC), Ki67, Survivin, and Bcl2-associated X protein (BAX). Surface characterization evidenced that collagen coating did not alter the nanotopography. Collagen coating increased cell proliferation, ALP activity, extracellular matrix mineralization, and Coll1a, OSX, OC, and BAX gene expression. Also, OPN and BSP proteins were strongly detected in cultures grown on both Ti surfaces. In conclusion, our results showed that the combination of nanotopography with collagen coating stimulates the early, intermediate, and final events of the in vitro osteogenesis and may be considered a potential approach to promote osseointegration of Ti implants. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 2783-2788, 2017. © 2017 Wiley Periodicals, Inc.
Conformal dip-coating of patterned surfaces for capillary die-to-substrate self-assembly
NASA Astrophysics Data System (ADS)
Mastrangeli, M.; Ruythooren, W.; Van Hoof, C.; Celis, J.-P.
2009-04-01
Capillarity-driven self-assembly of small chips onto planar target substrates is a promising alternative to robotic pick-and-place assembly. It critically relies on the selective deposition of thin fluid films on patterned binding sites, which is anyway normally non-conformal. We found that the addition of a thin wetting sidewall, surrounding the entire site perimeter, enables the conformal fluid coverage of arbitrarily shaped sites through dip-coating, significantly improves the reproducibility of the coating process and strongly reduces its sensitivity to surface defects. In this paper we support the feasibility and potential of this method by demonstrating the conformal dip-coating of square and triangular sites conditioned with combinations of different hydrophobic and hydrophilic surface chemistries. We present both experimental and simulative evidence of the advantages brought by the introduction of the wetting boundary on film coverage accuracy. Application of our surface preparation method to capillary self-assembly could result in higher precision in die-to-substrate registration and larger freedom in site shape design.
Hyun Kim; Sun-Young Yoo; Ji Sung Kim; Zihuan Wang; Woon Hee Lee; Kyo-In Koo; Jong-Mo Seo; Dong-Il Cho
2017-07-01
Inhibition of polydimethylsiloxane (PDMS) polymerization could be observed when spin-coated over vinyl substrates. The degree of polymerization, partially curing or fully curing, depended on the PDMS thickness coated over the vinyl substrate. This characteristic was exploited to achieve simple and fast PDMS patterning method using a vinyl adhesive layer patterned through a cutting plotter. The proposed patterning method showed results resembling PDMS etching. Therefore, patterning PDMS over PDMS, glass, silicon, and gold substrates were tested to compare the results with conventional etching methods. Vinyl stencils with widths ranging from 200μm to 1500μm were used for the procedure. To evaluate the accuracy of the cutting plotter, stencil designed on the AutoCAD software and the actual stencil widths were compared. Furthermore, this method's accuracy was also evaluated by comparing the widths of the actual stencils and etched PDMS results.
Watanabe, Satoshi; Akiyoshi, Yuri; Matsumoto, Mutsuyoshi
2014-01-01
We report a soft liquid-phase adsorption (SLPA) technique for the fabrication of organic semiconductor films on wettability-patterned substrates using toluene/water emulsions. Wettability-patterned substrates were obtained by the UV-ozone treatment of self-assembled monolayers of silane coupling agents on glass plates using a metal mask. Organic semiconductor polymer films were formed selectively on the hydrophobic part of the wettability-patterned substrates. The thickness of the films fabricated by the SLPA technique is significantly larger than that of the films fabricated by dip-coating and spin-coating techniques. The film thickness can be controlled by adjusting the volume ratio of toluene to water, immersion angle, immersion temperature, and immersion time. The SLPA technique allows for the direct production of organic semiconductor films on wettability-patterned substrates with minimized material consumption and reduced number of fabrication steps.
Bendas, Ehab R; Christensen, J Mark; Ayres, James W
2010-04-01
The basic objective of this study was to develop a novel technique that aids in compaction of coated pellets into tablets and obtain a release pattern from compressed pellets resembling the same pattern before compression. Multi-unit dosage forms of mesalamine targeted to the colon were formulated by extrusion-spheronization, and then coated with Eudragit S (30%). These pellets were filled into gelatin capsules or further formulated and compressed into tablets. Tablets for colonic delivery of mesalamine were prepared by mixing the coated beads with cushioning agents like stearic acid and Explotab, or by applying an additional coat of gelatin (4% weight gain) onto the Eudragit S coated pellets, and then compressing into tablets (tableted reservoir-type pellets). Then additional coating of the tablets prepared by the coating technique was applied utilizing Eudragit L 100-55 (5% weight gain). This technique provides additive protection for the coated beads to withstand the compression force during tableting. Excellent in vitro dissolution results were obtained, which were comparable to the results of the release of mesalamine from uncompressed beads filled in capsules. Mesalamine release from the capsules was 0.3% after 2 hours in gastric pH, 0.37% was released after an additional 1 hour in pH 6, and 89% was released after 1.5 hours in colonic pH 7.2. Various formulation and process parameters have to be optimized in order to obtain tableted reservoir-type pellets having the same release properties as the uncompressed pellets. The coating technique delays the release of mesalamine until the beads reach the terminal ileum and colon. Once released in the colon, mesalamine is minimally absorbed and can act locally to treat ulcerative colitis.
Kim, Youngjo; Lam, Nguyen Dinh; Kim, Kangho; Kim, Sangin; Rotermund, Fabian; Lim, Hanjo; Lee, Jaejin
2012-07-01
Single-junction GaAs solar cell structures were grown by low-pressure MOCVD on GaAs (100) substrates. Micro-rod arrays with diameters of 2 microm, 5 microm, and 10 microm were fabricated on the surfaces of the GaAs solar cells via photolithography and wet chemical etching. The patterned surfaces were coated with Au nanoparticles using an Au colloidal solution. Characteristics of the GaAs solar cells with and without the micro-rod arrays and Au nanoparticles were investigated. The short-circuit current density of the GaAs solar cell with 2 microm rod arrays and Au nanoparticles increased up to 34.9% compared to that of the reference cell without micro-rod arrays and Au nanoparticles. The conversion efficiency of the GaAs solar cell that was coated with Au nanoparticles on the patterned surface with micro-rod arrays can be improved from 14.1% to 19.9% under 1 sun AM 1.5G illumination. These results show that micro-rod arrays and Au nanoparticle coating can be applied together in surface patterning to achieve a novel cost-effective anti-reflection technology.
Kwon, Jinhyeong; Park, Shinyoung; Haque, Md Mominul; Kim, Young-Seok; Lee, Caroline Sunyong
2012-04-01
Sub-50 nm copper nanoparticles coated with sub-5 nm 1-octanethiol layer for oxidation inhibition were examined to confirm the 1-octanethiol removal temperature as the sub-50 nm copper nanoparticles are sintered. As a result, 1-octanethiol Self-Assembled Multi-layers (SAMs) on sub-50 nm copper nanoparticles were successfully removed before sintering of copper nanoparticles so that a high density of copper line could be obtained. Finally, the line resistivity was measured and compared to verify the effect of sintering in different atmospheres. As a result, electrical resistivity of the copper pattern sintered in hydrogen atmosphere was measured at 6.96 x 10(-6) ohm-cm whereas that of the copper pattern sintered in mixed gas atmosphere was measured at 2.62 x 10(-5) ohm-cm. Thus, sintering of copper patterns was successfully done to show low electrical resistivity values. Moreover, removal of 1-octanethiol coating after sintering process was confirmed using X-ray photoelectron spectroscopy (XPS) analysis. By showing no sulfur content, XPS results indicate that 1-octanethiol is completely removed. Therefore, the vapor form of 1-octanethiol coating layers can be safely used as an oxidation inhibition layer for low temperature sintering processes and ink-jet applications.
Liquid spreading on ceramic-coated carbon nanotube films and patterned microstructures
NASA Astrophysics Data System (ADS)
Zhao, Hangbo; Hart, A. John
2015-11-01
We study the capillary-driven liquid spreading behavior on films and microstructures of ceramic-coated vertically aligned carbon nanotubes (CNTs) fabricated on quartz substrates. The nanoscale porosity and micro-scale dimensions of the CNT structures, which can be precisely varied by the fabrication process, enable quantitative measurements that can be related to analytical models of the spreading behavior. Moreover, the conformal alumina coating by atomic layer deposition (ALD) prevents capillary-induced deformation of the CNTs upon meniscus recession, which has complicated previous studies of this topic. Washburn-like liquid spreading behavior is observed on non-patterned CNT surfaces, and is explained using a scaling model based on the balance of capillary driving force and the viscous drag force. Using these insights, we design patterned surfaces with controllable spreading rates and study the contact line pinning-depinning behavior. The nanoscale porosity, controllable surface chemistry, and mechanical stability of coated CNTs provide significantly enhanced liquid-solid interfacial area compared to solid microstructures. As a result, these surface designs may be useful for applications such as phase-change heat transfer and electrochemical energy storage. Funding for this project is provided by the National Institutes of Health and the MIT Center for Clean Water and Clean Energy supported by the King Fahd University of Petroleum and Minerals.
Microstructure Evolution of TiC Particles In Situ, Synthesized by Laser Cladding
Liu, Yanhui; Ding, Jieqiong; Qu, Weicheng; Su, Yu; Yu, Zhishui
2017-01-01
In this paper, a TiC reinforcement metal matrix composite coating is produced using nickel and graphite mixing powder on the surface ofTi-6Al-4V alloy by laser radiation. The microstructure of the coatings is investigated by XRD, SEM and EDS. Results show that most of the TiC phase is granular, with a size of several micrometers, and a few of the TiC phases are petals or flakes. At the cross-section of the coatings, a few special TiC patterns are found and these TiC patterns do not always occur at the observed cross-section. The even distribution of the TiC phase in the coatings confirms that the convection of the laser-melted pool leads to the homogenization of titanium atoms from the molten substrate, and carbon atoms from the preplace powder layer, by the mass transfer. The characteristics of the TiC pattern confirm that the morphology and distribution of the primary TiC phase could be influenced by convection. Two main reasons for this are that the density of the TiC phase is lower than the liquid melt, and that the primary TiC phase precipitates from the pool with a high convection speed at high temperature. PMID:28772641
Microstructure Evolution of TiC Particles In Situ, Synthesized by Laser Cladding.
Liu, Yanhui; Ding, Jieqiong; Qu, Weicheng; Su, Yu; Yu, Zhishui
2017-03-11
In this paper, a TiC reinforcement metal matrix composite coating is produced using nickel and graphite mixing powder on the surface ofTi-6Al-4V alloy by laser radiation. The microstructure of the coatings is investigated by XRD, SEM and EDS. Results show that most of the TiC phase is granular, with a size of several micrometers, and a few of the TiC phases are petals or flakes. At the cross-section of the coatings, a few special TiC patterns are found and these TiC patterns do not always occur at the observed cross-section. The even distribution of the TiC phase in the coatings confirms that the convection of the laser-melted pool leads to the homogenization of titanium atoms from the molten substrate, and carbon atoms from the preplace powder layer, by the mass transfer. The characteristics of the TiC pattern confirm that the morphology and distribution of the primary TiC phase could be influenced by convection. Two main reasons for this are that the density of the TiC phase is lower than the liquid melt, and that the primary TiC phase precipitates from the pool with a high convection speed at high temperature.
In-situ composite formation of damage tolerant coatings utilizing laser
Blue, Craig A [Knoxville, TN; Wong, Frank [Livermore, CA; Aprigliano, Louis F [Berlin, MD; Engleman, Peter G [Knoxville, TN; Peter, William H [Knoxville, TN; Rozgonyi, Tibor G [Golden, CO; Ozdemir, Levent [Golden, CO
2011-05-10
A coating steel component with a pattern of an iron based matrix with crystalline particles metallurgically bound to the surface of a steel substrate for use as disc cutters or other components with one or more abrading surfaces that can experience significant abrasive wear, high point loads, and large shear stresses during use. The coated component contains a pattern of features in the shape of freckles or stripes that are laser formed and fused to the steel substrate. The features can display an inner core that is harder than the steel substrate but generally softer than the matrix surrounding the core, providing toughness and wear resistance to the features. The features result from processing an amorphous alloy where the resulting matrix can be amorphous, partially devitrified or fully devitrified.
In-situ composite formation of damage tolerant coatings utilizing laser
Blue, Craig A; Wong, Frank; Aprigliano, Louis F; Engleman, Peter G; Rozgonyi, Tibor G; Ozdemir, Levent
2014-03-18
A coating steel component with a pattern of an iron based matrix with crystalline particles metallurgically bound to the surface of a steel substrate for use as disc cutters or other components with one or more abrading surfaces that can experience significant abrasive wear, high point loads, and large shear stresses during use. The coated component contains a pattern of features in the shape of freckles or stripes that are laser formed and fused to the steel substrate. The features can display an inner core that is harder than the steel substrate but generally softer than the matrix surrounding the core, providing toughness and wear resistance to the features. The features result from processing an amorphous alloy where the resulting matrix can be amorphous, partially devitrified or fully devitrified.
NASA Astrophysics Data System (ADS)
Chen, Sujie; Li, Siying; Peng, Sai; Huang, Yukun; Zhao, Jiaqing; Tang, Wei; Guo, Xiaojun
2018-01-01
Soft conductive films composed of a silver nanowire (AgNW) network, a neutral-pH PEDOT:PSS over-coating layer and a polydimethylsiloxane (PDMS) elastomer substrate are fabricated by large area compatible coating processes. The neutral-pH PEDOT:PSS layer is shown to be able to significantly improve the conductivity, stretchability and air stability of the conductive films. The soft conductive films are patterned using a simple maskless patterning approach to fabricate an 8 × 8 flexible pressure sensor array. It is shown that such soft conductive films can help to improve the sensitivity and reduce the signal crosstalk over the pressure sensor array. Project supported by the Science and Technology Commission of Shanghai Municipality (No. 16JC1400603).
In-situ composite formation of damage tolerant coatings utilizing laser
Blue, Craig A.; Wong, Frank; Aprigliano, Louis F.; Engleman, Peter G.; Peter, William H.; Rozgonyi, Tibor G.; Ozdemir, Levent
2016-05-24
A coating steel component with a pattern of an iron based matrix with crystalline particles metallurgically bound to the surface of a steel substrate for use as disc cutters or other components with one or more abrading surfaces that can experience significant abrasive wear, high point loads, and large shear stresses during use. The coated component contains a pattern of features in the shape of freckles or stripes that are laser formed and fused to the steel substrate. The features can display an inner core that is harder than the steel substrate but generally softer than the matrix surrounding the core, providing toughness and wear resistance to the features. The features result from processing an amorphous alloy where the resulting matrix can be amorphous, partially devitrified or fully devitrified.
Graeber, Kai; Linkies, Ada; Steinbrecher, Tina; Mummenhoff, Klaus; Tarkowská, Danuše; Turečková, Veronika; Ignatz, Michael; Sperber, Katja; Voegele, Antje; de Jong, Hans; Urbanová, Terezie; Strnad, Miroslav; Leubner-Metzger, Gerhard
2014-08-26
Seed germination is an important life-cycle transition because it determines subsequent plant survival and reproductive success. To detect optimal spatiotemporal conditions for germination, seeds act as sophisticated environmental sensors integrating information such as ambient temperature. Here we show that the delay of germination 1 (DOG1) gene, known for providing dormancy adaptation to distinct environments, determines the optimal temperature for seed germination. By reciprocal gene-swapping experiments between Brassicaceae species we show that the DOG1-mediated dormancy mechanism is conserved. Biomechanical analyses show that this mechanism regulates the material properties of the endosperm, a seed tissue layer acting as germination barrier to control coat dormancy. We found that DOG1 inhibits the expression of gibberellin (GA)-regulated genes encoding cell-wall remodeling proteins in a temperature-dependent manner. Furthermore we demonstrate that DOG1 causes temperature-dependent alterations in the seed GA metabolism. These alterations in hormone metabolism are brought about by the temperature-dependent differential expression of genes encoding key enzymes of the GA biosynthetic pathway. These effects of DOG1 lead to a temperature-dependent control of endosperm weakening and determine the optimal temperature for germination. The conserved DOG1-mediated coat-dormancy mechanism provides a highly adaptable temperature-sensing mechanism to control the timing of germination.
Evolving lessons on nanomaterial-coated viral vectors for local and systemic gene therapy
Kasala, Dayananda; Yoon, A-Rum; Hong, Jinwoo; Kim, Sung Wan; Yun, Chae-Ok
2016-01-01
Viral vectors are promising gene carriers for cancer therapy. However, virus-mediated gene therapies have demonstrated insufficient therapeutic efficacy in clinical trials due to rapid dissemination to nontarget tissues and to the immunogenicity of viral vectors, resulting in poor retention at the disease locus and induction of adverse inflammatory responses in patients. Further, the limited tropism of viral vectors prevents efficient gene delivery to target tissues. In this regard, modification of the viral surface with nanomaterials is a promising strategy to augment vector accumulation at the target tissue, circumvent the host immune response, and avoid nonspecific interactions with the reticuloendothelial system or serum complement. In the present review, we discuss various chemical modification strategies to enhance the therapeutic efficacy of viral vectors delivered either locally or systemically. We conclude by highlighting the salient features of various nanomaterial-coated viral vectors and their prospects and directions for future research. PMID:27348247
Wang, Zhongshan; Wu, Guofeng; Bai, Shizhu; Feng, Zhihong; Dong, Yan; Zhou, Jian; Qin, Haiyan; Zhao, Yimin
2014-06-01
Infection and epithelial downgrowth are two major problems with maxillofacial transcutaneous implants, and both are mainly due to lack of stable closure of soft tissues at transcutaneous sites. Fibroblasts have been shown to play a key role in the formation of biological seals. In this work, titanium (Ti) model surfaces were coated with mussel adhesive proteins (MAPs) utilizing its unique adhesion ability on diverse inorganic and organic surfaces in wet environments. Prepared basic fibroblast growth factor (bFGF)-poly(lactic-co-glycolic acid) (PLGA) microspheres can be easily synthesized and combined onto MAPs-coated Ti surfaces, due to the negative surface charges of microspheres in aqueous solution, which is in contrast to the positive charges of MAPs. Titanium model surfaces were divided into three groups. Group A: MAPs/bFGF-PLGA microspheres composite-coated Ti surfaces. Group B: MAPs-coated Ti surfaces. Group C: uncoated Ti surfaces. The effects of coated Ti surfaces on adhesion of fibroblasts, cytoskeletal organization, proliferation, and extracellular matrix (ECM)-related gene expressions were examined. The results revealed increased adhesion (P < 0.05), enhanced actin cytoskeletal organization, and up-regulated ECM-related gene expressions in groups A and B compared with group C. Increased proliferation of fibroblasts during five days of incubation was observed in group A compared with groups B and C (P < 0.05). Collectively, the results from this in vitro study demonstrated that MAPs/bFGF-PLGA microspheres composite-coated Ti surfaces had the ability to increase fibroblast functionality. In addition, MAPs/bFGF-PLGA microsphere composite-coated Ti surfaces should be studied further as a method of promoting formation of stable biological seals around transcutaneous sites.
Gems, D; Maizels, R M
1996-01-01
Evasion of host immunity by Toxocara canis infective larvae is mediated by the nematode surface coat, which is shed in response to binding by host antibody molecules or effector cells. The major constituent of the coat is the TES-120 glycoprotein series. We have isolated a 730-bp cDNA from the gene encoding the apoprotein precursor of TES-120. The mRNA is absent from T. canis adults but hyperabundant in larvae, making up approximately 10% of total mRNA, and is trans-spliced with the nematode 5' leader sequence SL1. It encodes a 15.8-kDa protein (after signal peptide removal) containing a typical mucin domain: 86 amino acid residues, 72.1% of which are Ser or Thr, organized into an array of heptameric repeats, interspersed with proline residues. At the C-terminal end of the putative protein are two 36-amino acid repeats containing six Cys residues, in a motif that can also be identified in several genes in Caenorhabditis elegans. Although TES-120 displays size and charge heterogeneity, there is a single copy gene and a homogeneous size of mRNA. The association of overexpression of some membrane-associated mucins with immunosuppression and tumor metastasis suggests a possible model for the role of the surface coat in immune evasion by parasitic nematodes. Images Fig. 1 Fig. 4 PMID:8643687
Coated substrate apparatus and method
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bao, Zhenan; Diao, Ying; Mannsfeld, Stefan Christian Bernhardt
A coated substrate is formed with aligned objects such as small molecules, macromolecules and nanoscale particulates, such as inorganic, organic or inorganic/organic hybrid materials. In accordance with one or more embodiments, an apparatus or method involves an applicator having at least one surface patterned with protruded or indented features, and a coated substrate including a solution-based layer of objects having features and morphology attributes arranged as a function of the protruded or indented features.
Magnetic iron oxide nanoparticles mediated gene therapy for breast cancer--an in vitro study.
Wei, Weizhong; Xu, Chunfang; Wu, Hua
2006-01-01
The aim of this study was to evaluate the feasibility and efficacy of using TRAIL gene to treat breast cancer mediated with a novel carrier - magnetic iron oxide nanoparticles (poly-MAG-1000) coated with PEI. The magnetic iron oxide nanoparticles were used as gene carrier to transfect TRAIL gene into MCF-7 cells. The polyMAG-1000 without TRAIL gene was transfected into the tumor cells as negative control. TRAIL gene transfection with liposome as carrier served as positive control. The apoptosis of cells was detected with TUNEL method. The apoptosis ratio of tumor cells was measured with flow cytometry (FCM). It was found that the apoptosis occurred in the tumor cells after transfection of TRAIL gene mediated by both polyMAG-1000 and liposome. The apoptosis ratio in the group with polyMAG-1000 as gene carrier was (25.11+/-2.85) %, whereas it was (5.06+/- 1.05) % in the control group with polyMAG-1000 (P<0.01). The apoptosis ratio was as low as (18.31+/-2.44) % in the group with liposome as gene carrier (P<0.05, as compared with the group with polyMAG-1000 as gene carrier). It is suggested that TRAIL gene may induce apoptosis in MCF-7 breast cancer cells. The magnetic iron oxide nanoparticles coated with PEI may be a potential gene carrier with high transfection efficacy for cancer gene therapy..
How do tablet properties influence swallowing behaviours?
Yamamoto, Shinya; Taniguchi, Hiroshige; Hayashi, Hirokazu; Hori, Kazuhiro; Tsujimura, Takanori; Nakamura, Yuki; Sato, Hideaki; Inoue, Makoto
2014-01-01
Behavioural performance of tablet swallowing was evaluated with different tablet conditions in terms of size, number and surface coating. Four different types of tablets were prepared: small or large, and with or without a surface coating. Fourteen normal male adults were instructed to swallow the prepared tablets with 15 ml of water. The number of tablets in one trial was changed from one to three. To evaluate swallowing and tablet transport, electromyographic activity was recorded in the left suprahyoid muscles, and videofluorographic images were examined. All tablet conditions (size, number and surface coating) affected the swallowing performance in terms of total number of swallows, electromyographic burst patterns and location of remaining tablets. Increases in the size and number of tablets increased the number of swallows and electromyographic burst area and duration. In addition, all of these parameters increased while swallowing tablets without a coating compared with tablets with a coating. Location of the remaining tablets was mainly within the mouth. This study only clarified the normal pattern of tablet swallowing under several conditions in healthy subjects, but the results may facilitate comprehensive evaluation and treatment planning in terms of administering medication to dysphagic patients. © 2013 Royal Pharmaceutical Society.
NASA Astrophysics Data System (ADS)
Chen, Hsien-Yeh
Functionalized poly(p-xylylenes) or so-called reactive polymers can be synthesized via chemical vapor deposition (CVD) polymerization. The resulting ultra-thin coatings are pinhole-free and can be conformally deposited to a wide range of substrates and materials. More importantly, the equipped functional groups can served as anchoring sites for tailoring the surface properties, making these reactive coatings a robust platform that can deal with sophisticated challenges faced in biointerfaces. In this work presented herein, surface coatings presenting various functional groups were prepared by CVD process. Such surfaces include aldehyde-functionalized coating to precisely immobilize saccharide molecules onto well-defined areas and alkyne-functionalized coating to click azide-modified molecules via Huisgen 1,3-dipolar cycloaddition reaction. Moreover, CVD copolymerization has been conducted to prepare multifunctional coatings and their specific functions were demonstrated by the immobilization of biotin and NHS-ester molecules. By using a photodefinable coating, polyethylene oxides were immobilized onto a wide range of substrates through photo-immobilization. Spatially controlled protein resistant properties were characterized by selective adsorption of fibrinogen and bovine serum albumin as model systems. Alternatively, surface initiator coatings were used for polymer graftings of polyethylene glycol) methyl ether methacrylate, and the resultant protein- and cell- resistant properties were characterized by adsorption of kinesin motor proteins, fibrinogen, and murine fibroblasts (NIH3T3). Accessibility of reactive coatings within confined microgeometries was systematically studied, and the preparation of homogeneous polymer thin films within the inner surface of microchannels was demonstrated. Moreover, these advanced coatings were applied to develop a dry adhesion process for microfluidic devices. This process provides (i) excellent bonding strength, (ii) extended storage time prior to bonding, and (iii) well-defined surface functionalities for subsequent surface modifications. Finally, we have also prepared surface microstructures and surface patterns using reactive coatings via photopatterning, projection lithography, supramolecular nanostamping (SuNS), and vapor-assisted micropatterning in replica structures (VAMPIR). These patterning techniques can be complimentarily used and provide access to precisely confined microenvironments on flat and curved geometries. Reactive coatings provide a technology platform that creates active, long-term control and may lead to improved mimicry of biological systems for effective bio-functional modifications.
Transmitting and reflecting diffuser. [for ultraviolet light
NASA Technical Reports Server (NTRS)
Keafer, L. S., Jr.; Burcher, E. E.; Kopia, L. P. (Inventor)
1973-01-01
A near-Lambertian diffuser is described which transmits and reflects ultraviolet light. An ultraviolet grade fused silica substrate is coated with vaporized fuse silica. The coating thickness is controlled, one thickness causing ultraviolet light to diffuse and another thickness causing ultraviolet light to reflect a near Lambertian pattern.
GmHs1-1, encoding a calcineurin-like protein, controls hard-seededness in soybean
USDA-ARS?s Scientific Manuscript database
Loss of seed-coat impermeability was an essential step towards domestication of many leguminous crops for production of their highly nutritious seeds. Here we show that seed-coat impermeability in wild soybean is controlled by a single gene, Hard seededness 1 (Hs1), which encodes a calcineurin-like ...
Federal Register 2010, 2011, 2012, 2013, 2014
2010-11-17
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Transfer molding processes for nanoscale patterning of poly-L-lactic acid (PLLA) films
NASA Astrophysics Data System (ADS)
Dhakal, Rabin; Peer, Akshit; Biswas, Rana; Kim, Jaeyoun
2016-03-01
Nanoscale patterned structures composed of biomaterials exhibit great potential for the fabrication of functional biostructures. In this paper, we report cost-effective, rapid, and highly reproducible soft lithographic transfer-molding techniques for creating periodic micro- and nano-scale textures on poly (L-lactic acid) (PLLA) surface. These artificial textures can increase the overall surface area and change the release dynamics of the therapeutic agents coated on it. Specifically, we use the double replication technique in which the master pattern is first transferred to the PDMS mold and the pattern on PDMS is then transferred to the PLLA films through drop-casting as well as nano-imprinting. The ensuing comparison studies reveal that the drop-cast PLLA allows pattern transfer at higher levels of fidelity, enabling the realization of nano-hole and nano-cone arrays with pitch down to ~700 nm. The nano-patterned PLLA film was then coated with rapamycin to make it drug-eluting.
Spore coat protein of Bacillus subtilis. Structure and precursor synthesis.
Munoz, L; Sadaie, Y; Doi, R H
1978-10-10
The coat protein of Bacillus subtilis spores comprises about 10% of the total dry weight of spores and 25% of the total spore protein. One protein with a molecular weight of 13,000 to 15,000 comprises a major portion of the spore coat. This mature spore coat protein has histidine at its NH2 terminus and is relatively rich in hydrophobic amino acids. Netropsin, and antibiotic which binds to A-T-rich regions of DNA and inhibits sporulation, but not growth, decreased the synthesis of this spore coat protein by 75%. A precursor spore coat protein with a molecular weight of 25,000 is made initially at t1 of sporulation and is converted to the mature spore coat protein with a molecular weight of 13,500 at t2 - t3. These data indicate that the spore coat protein gene is expressed very early in sporulation prior to the modifications of RNA polymerase which have been noted.
Lenzner, Steffen; Prietz, Sandra; Feil, Silke; Nuber, Ulrike A; Ropers, H-Hilger; Berger, Wolfgang
2002-09-01
Mutations in the NDP gene give rise to a variety of eye diseases, including classic Norrie disease (ND), X-linked exudative vitreoretinopathy (EVRX), retinal telangiectasis (Coats disease), and advanced retinopathy of prematurity (ROP). The gene product is a cystine-knot-containing extracellular signaling molecule of unknown function. In the current study, gene expression was determined in a mouse model of ND, to unravel disease-associated mechanisms at the molecular level. Gene transcription in the eyes of 2-year-old Ndp knockout mice was compared with that in the eyes of age-matched wild-type control animals, by means of cDNA subtraction and microarrays. Clones (n = 3072) from the cDNA subtraction libraries were spotted onto glass slides and hybridized with fluorescently labeled RNA-derived targets. More than 230 differentially expressed clones were sequenced, and their expression patterns were verified by virtual Northern blot analysis. Numerous gene transcripts that are absent or downregulated in the eye of Ndp knockout mice are photoreceptor cell specific. In younger Ndp knockout mice (up to 1 year old), however, all these transcripts were found to be expressed at normal levels. The identification of numerous photoreceptor cell-specific transcripts with a reduced expression in 2-year-old, but not in young, Ndp knockout mice indicates that normal gene expression in these light-sensitive cells of mutant mice is established and maintained over a long period and that rods and cones are affected relatively late in the mouse model of ND. Obviously, the absence of the Ndp gene product is not compatible with long-term survival of photoreceptor cells in the mouse.
Polyploidization altered gene functions in cotton (Gossypium spp.)
USDA-ARS?s Scientific Manuscript database
Cotton fibers are seed trichomes derived from individual cells of the epidermal layer of the seed coat. It has been known for a long time that a large set of genes determine the development of cotton fiber, and more recently it has been determined that these genes are distributed across the At and ...
Genetics and Biochemistry of Zero-Tannin Lentils.
Mirali, Mahla; Purves, Randy W; Stonehouse, Rob; Song, Rui; Bett, Kirstin; Vandenberg, Albert
2016-01-01
The zero-tannin trait in lentil is controlled by a single recessive gene (tan) that results in a phenotype characterized by green stems, white flowers, and thin, transparent, or translucent seed coats. Genes that result in zero-tannin characteristics are useful for studies of seed coat pigmentation and biochemical characters because they have altered pigmentation. In this study, one of the major groups of plant pigments, phenolic compounds, was compared among zero-tannin and normal phenotypes and genotypes of lentil. Biochemical data were obtained by liquid chromatography-mass spectrometry (LC-MS). Genomic sequencing was used to identify a candidate gene for the tan locus. Phenolic compound profiling revealed that myricetin, dihydromyricetin, flavan-3-ols, and proanthocyanidins are only detected in normal lentil phenotypes and not in zero-tannin types. The molecular analysis showed that the tan gene encodes a bHLH transcription factor, homologous to the A gene in pea. The results of this study suggest that tan as a bHLH transcription factor interacts with the regulatory genes in the biochemical pathway of phenolic compounds starting from flavonoid-3',5'-hydroxylase (F3'5'H) and dihydroflavonol reductase (DFR).
Tsai, Hsin-Yi; Vats, Kanika; Yates, Matthew Z.; Benoit, Danielle S. W.
2013-01-01
Thermoresponsive poly(N-isopropyl acrylamide) (PNIPAM) microgels were patterned on polystyrene substrates via dip coating, creating cytocompatible substrates that provided spatial control over cell adhesion. This simple dip coating method, which exploits variable substrate withdrawal speeds form particle suspension formed stripes of densely-packed PNIPAM microgels, while spacings between the stripes contained sparsely-distributed PNIPAM microgels. The assembly of three different PNIPAM microgel patterns, namely patterns composed of 50 μm stripes/50 μm spacings, 50 μm stripes/100 μm spacings, and 100 μm stripes/100 μm spacings was verified using high-resolution optical micrographs and ImageJ analysis. PNIPAM microgels existed as monolayers within stripes and spacings, as revealed by atomic force microscopy (AFM). Upon cell seeding on PNIPAM micropatterned substrates, NIH3T3 fibroblast cells preferentially adhered within spacings to form cell patterns. Three days after cell seeding, cells proliferated to form confluent cell layers. The thermoresponsiveness of the underlying PNIPAM microgels was then utilized to recover fibroblast cell sheets from substrates simply by lowering the temperature, without disrupting the underlying PNIPAM microgel patterns. Harvested cell sheets similar to these have been used for multiple tissue engineering applications. Also, this simple, low cost, template-free dip coating technique can be utilized to micropattern multifunctional PNIPAM microgels, generating complex stimuli-responsive substrates to study cell-material interactions and allow drug delivery to cells in a spatially and temporally-controlled manners. PMID:23968193
Connahs, Heidi; Rhen, Turk; Simmons, Rebecca B
2016-03-31
Butterfly wing color patterns are an important model system for understanding the evolution and development of morphological diversity and animal pigmentation. Wing color patterns develop from a complex network composed of highly conserved patterning genes and pigmentation pathways. Patterning genes are involved in regulating pigment synthesis however the temporal expression dynamics of these interacting networks is poorly understood. Here, we employ next generation sequencing to examine expression patterns of the gene network underlying wing development in the nymphalid butterfly, Vanessa cardui. We identified 9, 376 differentially expressed transcripts during wing color pattern development, including genes involved in patterning, pigmentation and gene regulation. Differential expression of these genes was highest at the pre-ommochrome stage compared to early pupal and late melanin stages. Overall, an increasing number of genes were down-regulated during the progression of wing development. We observed dynamic expression patterns of a large number of pigment genes from the ommochrome, melanin and also pteridine pathways, including contrasting patterns of expression for paralogs of the yellow gene family. Surprisingly, many patterning genes previously associated with butterfly pattern elements were not significantly up-regulated at any time during pupation, although many other transcription factors were differentially expressed. Several genes involved in Notch signaling were significantly up-regulated during the pre-ommochrome stage including slow border cells, bunched and pebbles; the function of these genes in the development of butterfly wings is currently unknown. Many genes involved in ecdysone signaling were also significantly up-regulated during early pupal and late melanin stages and exhibited opposing patterns of expression relative to the ecdysone receptor. Finally, a comparison across four butterfly transcriptomes revealed 28 transcripts common to all four species that have no known homologs in other metazoans. This study provides a comprehensive list of differentially expressed transcripts during wing development, revealing potential candidate genes that may be involved in regulating butterfly wing patterns. Some differentially expressed genes have no known homologs possibly representing genes unique to butterflies. Results from this study also indicate that development of nymphalid wing patterns may arise not only from melanin and ommochrome pigments but also the pteridine pigment pathway.
Biolistic transfection of neuronal cultures using a hand-held gene gun
O'Brien, John A; Lummis, Sarah C R
2009-01-01
Biolistic transfection is a technique in which subcellular-sized particles coated with DNA are accelerated to high velocity to propel them into cells. This method is applicable to tissues, cells and organelles, and can be used for both in vitro and in vivo transformations; with the right equipment, it is simple, rapid and efficient. Here we provide a detailed protocol for biolistic transfection of plasmids into cultured human embryonic kidney (HEK) 293 cells and organotypic brain slices using a hand-held gene gun. There are three major steps: (i) coating microcarriers with DNA, (ii) transferring the microcarriers into a cartridge to make a ‘bullet’, and (iii) firing the DNA-coated microcarriers into cells using a pulse of helium gas. The method can be readily adapted to other cell types and tissues. The protocol can be completed in 1–2 h. PMID:17406333
Zhang, Lan; Han, Yong; Tan, Guoxin
2015-03-01
Percutaneous implant requires a tight bond between the underlying dermis of skin and implant surface to prevent epithelial down-growth and infection, while fibroblasts play a key role in the skin-implant integration. In this work, nanorod-shaped hydroxyaptite (HA) with a mean diameter of 70 nm and length of 400 nm was hydrothermally grown on micro-arc oxidized (MAOed) Ca- and P-doped ZrO2 to form a bilayer coating. The hydrothermal formation mechanism of HA nanorods was explored, and the adsorption of total protein on the coating from α-MEM medium containing 10% fetal bovine serum was examined. Employing L-929 cells, the behaviors of fibroblasts on the bilayer coating, including adhesion and proliferation were evaluated together the polished Zr and as-MAOed ZrO2. The obtained results show that the HA nanorods nucleated on ZrO2 and grew at the expense of the doped Ca and P ions during the hydrothermal treatment (HT). The HA nanorods patterned coating enhanced protein absorption, and significantly improved the adhesion and proliferation of fibroblasts compared to the as-MAOed ZrO2 and polished Zr. It suggests that the HA nanorods/ZrO2 coated zirconium has a potential application for percutaneous implants to enhance the attachment of skin. Copyright © 2015 Elsevier B.V. All rights reserved.
The complete nucleotide sequence of RNA 3 of a peach isolate of Prunus necrotic ringspot virus.
Hammond, R W; Crosslin, J M
1995-04-01
The complete nucleotide sequence of RNA 3 of the PE-5 peach isolate of Prunus necrotic ringspot ilarvirus (PNRSV) was obtained from cloned cDNA. The RNA sequence is 1941 nucleotides and contains two open reading frames (ORFs). ORF 1 consisted of 284 amino acids with a calculated molecular weight of 31,729 Da and ORF 2 contained 224 amino acids with a calculated molecular weight of 25,018 Da. ORF 2 corresponds to the coat protein gene. Expression of ORF 2 engineered into a pTrcHis vector in Escherichia coli results in a fusion polypeptide of approximately 28 kDa which cross-reacts with PNRSV polyclonal antiserum. Analysis of the coat protein amino acid sequence reveals a putative "zinc-finger" domain at the amino-terminal portion of the protein. Two tetranucleotide AUGC motifs occur in the 3'-UTR of the RNA and may function in coat protein binding and genome activation. ORF 1 homologies to other ilarviruses and alfalfa mosaic virus are confined to limited regions of conserved amino acids. The translated amino acid sequence of the coat protein gene shows 92% similarity to one isolate of apple mosaic virus, a closely related member of the ilarvirus group of plant viruses, but only 66% similarity to the amino acid sequence of the coat protein gene of a second isolate. These relationships are also reflected at the nucleotide sequence level. These results in one instance confirm the close similarities observed at the biophysical and serological levels between these two viruses, but on the other hand call into question the nomenclature used to describe these viruses.
Takamatsu, Hiromu; Kodama, Takeko; Nakayama, Tatsuo; Watabe, Kazuhito
1999-01-01
Insertional inactivation of the yrbA gene of Bacillus subtilis reduced the resistance of the mutant spores to lysozyme. The yrbA mutant spores lost their optical density at the same rate as the wild-type spores upon incubation with l-alanine but became only phase gray and did not swell. The response of the mutant spores to a combination of asparagine, glucose, fructose, and KCl was also extremely poor; in this medium yrbA spores exhibited only a small loss in optical density and gave a mixture of phase-bright, -gray, and -dark spores. Northern blot analysis of yrbA transcripts in various sig mutants indicated that yrbA was transcribed by RNA polymerase with ςE beginning at 2 h after the start of sporulation. The yrbA promoter was localized by primer extension analysis, and the sequences of the −35 (TCATAAC) and −10 (CATATGT) regions were similar to the consensus sequences of genes recognized by ςE. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis of proteins solubilized from intact yrbA mutant spores showed an alteration in the protein profile, as 31- and 36-kDa proteins, identified as YrbA and CotG, respectively, were absent, along with some other minor changes. Electron microscopic examination of yrbA spores revealed changes in the spore coat, including a reduction in the density and thickness of the outer layer and the appearance of an inner coat layer-like structure around the outside of the coat. This abnormal coat structure was also observed on the outside of the developing forespores of the yrbA mutant. These results suggest that YrbA is involved in assembly of some coat proteins which have roles in both spore lysozyme resistance and germination. PMID:10438771
Localized analysis of paint-coat drying using dynamic speckle interferometry
NASA Astrophysics Data System (ADS)
Sierra-Sosa, Daniel; Tebaldi, Myrian; Grumel, Eduardo; Rabal, Hector; Elmaghraby, Adel
2018-07-01
The paint-coating is part of several industrial processes, including the automotive industry, architectural coatings, machinery and appliances. These paint-coatings must comply with high quality standards, for this reason evaluation techniques from paint-coatings are in constant development. One important factor from the paint-coating process is the drying, as it has influence on the quality of final results. In this work we present an assessment technique based on the optical dynamic speckle interferometry, this technique allows for the temporal activity evaluation of the paint-coating drying process, providing localized information from drying. This localized information is relevant in order to address the drying homogeneity, optimal drying, and quality control. The technique relies in the definition of a new temporal history of the speckle patterns to obtain the local activity; this information is then clustered to provide a convenient indicative of different drying process stages. The experimental results presented were validated using the gravimetric drying curves
Fe3O4 Nanoparticles in Targeted Drug/Gene Delivery Systems
Shen, Lazhen; Li, Bei; Qiao, Yongsheng
2018-01-01
Fe3O4 nanoparticles (NPs), the most traditional magnetic nanoparticles, have received a great deal of attention in the biomedical field, especially for targeted drug/gene delivery systems, due to their outstanding magnetism, biocompatibility, lower toxicity, biodegradability, and other features. Naked Fe3O4 NPs are easy to aggregate and oxidize, and thus are often made with various coatings to realize superior properties for targeted drug/gene delivery. In this review, we first list the three commonly utilized synthesis methods of Fe3O4 NPs, and their advantages and disadvantages. In the second part, we describe coating materials that exhibit noticeable features that allow functionalization of Fe3O4 NPs and summarize their methods of drug targeting/gene delivery. Then our efforts will be devoted to the research status and progress of several different functionalized Fe3O4 NP delivery systems loaded with chemotherapeutic agents, and we present targeted gene transitive carriers in detail. In the following section, we illuminate the most effective treatment systems of the combined drug and gene therapy. Finally, we propose opportunities and challenges of the clinical transformation of Fe3O4 NPs targeting drug/gene delivery systems. PMID:29473914
Formation of Nanoparticle Stripe Patterns via Flexible-Blade Flow Coating
NASA Astrophysics Data System (ADS)
Lee, Dong Yun; Kim, Hyun Suk; Parkos, Cassandra; Lee, Cheol Hee; Emrick, Todd; Crosby, Alfred
2011-03-01
We present the controlled formation of nanostripe patterns of nanoparticles on underlying substrates by flexible-blade flow coating. This technique exploits the combination of convective flow of confined nanoparticle solutions and programmed translation of a substrate to fabricate nanoparticle-polymer line assemblies with width below 300 nm, thickness of a single nanoparticle, and lengths exceeding 10 cm. We demonstrate how the incorporation of a flexible blade into this technique allows capillary forces to self-regulate the uniformity of convective flow processes across large lateral lengths. Furthermore, we exploit solvent mixture dynamics to enhance intra-assembly particle packing and dimensional range. This facile technique opens up a new paradigm for integration of nanoscale patterns over large areas for various applications.
Zhou, Jianhong; Li, Bo; Han, Yong; Zhao, Lingzhou
2016-07-01
Advanced titanium based bone implant with fast established, rigid and stable osseointegration is stringently needed in clinic. Here the hierarchical micropore/nanorod-patterned strontium doped hydroxyapatite (Ca9Sr1(PO4)6(OH)2, Sr1-HA) coatings (MNRs) with different interrod spacings varying from about 300 to 33nm were developed. MNRs showed dramatically differential biological performance closely related to the interrod spacing. Compared to micropore/nanogranule-patterned Sr1-HA coating (MNG), MNRs with an interrod spacing of larger than 137nm resulted in inhibited in vitro mesenchymal stem cell functions and in vivo osseointegration, while those of smaller than 96nm gave rise to dramatically enhanced the biological effect, especially those of mean 67nm displayed the best effect. The differential biological effect of MNRs was related to their modulation on the focal adhesion mediated mechanotransduction. These results suggest that MNRs with a mean interrod spacing of 67nm may give rise to an advanced implant of improved clinical performance. Copyright © 2016 Elsevier Inc. All rights reserved.
Nigenda-Morales, Sergio F; Hu, Yibo; Beasley, James C; Ruiz-Piña, Hugo A; Valenzuela-Galván, David; Wayne, Robert K
2018-06-01
Skin pigmentation and coat pigmentation are two of the best-studied examples of traits under natural selection given their quantifiable fitness interactions with the environment (e.g., camouflage) and signalling with other organisms (e.g., warning coloration). Previous morphological studies have found that skin pigmentation variation in the Virginia opossum (Didelphis virginiana) is associated with variation in precipitation and temperatures across its distribution range following Gloger's rule (lighter pigmentation in temperate environments). To investigate the molecular mechanism associated with skin pigmentation variation, we used RNA-Seq and quantified gene expression of wild opossums from tropical and temperate populations. Using differential expression analysis and a co-expression network approach, we found that expression variation in genes with melanocytic and immune functions is significantly associated with the degree of skin pigmentation variation and may be underlying this phenotypic difference. We also found evidence suggesting that the Wnt/β-catenin signalling pathway might be regulating the depigmentation observed in temperate populations. Based on our study results, we present several alternative hypotheses that may explain Gloger's rule pattern of skin pigmentation variation in opossum, including changes in pathogen diversity supporting a pathogen-resistant hypothesis, thermal stress associated with temperate environments, and pleiotropic and epistatic interactions between melanocytic and immune genes. © 2018 John Wiley & Sons Ltd.
Association analysis of KIT, MITF, and PAX3 variants with white markings in Spanish horses.
Negro, S; Imsland, F; Valera, M; Molina, A; Solé, M; Andersson, L
2017-06-01
Several variants in the KIT, PAX3 and MITF genes have previously been associated with white markings in horses. In this study, we examined eight variants of these genes in 70 Menorca Purebred horses (PRMe, only black solid-coloured horses) and 70 Spanish Purebred horses (PRE, different coat colour patterns) that were scored for the extent of white markings. A maximum-likelihood chi-square test, logistic regression model and ridge regression analyses showed that a missense mutation (p.Arg682His) in KIT was associated with white facial markings (P < 0.05) and with total white markings (P < 0.05) in PRMe horses. The relative contribution of this variant to white markings in PRMe horses was estimated at 47.6% (head) and 43.4% (total score). In PRE horses, this variant was also associated with hindlimb scores (P < 0.05) with a relative contribution of 41.2%. The g.20147039C>T intronic variant located 29.9 kb downstream from the transcription start site of the MITF gene was associated with less white markings on forelimbs (P < 0.05) in PRMe horses, with a relative contribution of 63.9%, whereas in PRE horses this variant was associated with white facial markings (P < 0.05), with a relative contribution of 63.9%. No significant associations were found for PAX3 variants in these breeds. These results show that KIT and MITF variants are involved in the white marking patterns of both PRMe and PRE horses, providing breeders with an opportunity to use genetic testing to aid in breeding for their desired level of white markings. © 2017 Stichting International Foundation for Animal Genetics.
Mirali, Mahla; Purves, Randy W; Vandenberg, Albert
2017-05-26
Phenolic compounds can provide antioxidant health benefits for humans, and foods such as lentils can be valuable dietary sources of different subclasses of these secondary metabolites. This study used LC-MS analyses to compare the phenolic profiles of lentil genotypes with four seed coat background colors (green, gray, tan, and brown) and two cotyledon colors (red and yellow) grown at two locations. The mean area ratio per mg sample (MARS) values of various phenolic compounds in lentil seeds varied with the different seed coat colors conferred by specific genotypes. Seed coats of lentil genotypes with the homozygous recessive tgc allele (green and gray seed coats) had higher MARS values of flavan-3-ols, proanthocyanidins, and some flavonols. This suggests lentils featuring green and gray seed coats might be more promising as health-promoting foods.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Oswald, S.G.; Van Nostrand, D.; Savory, C.G.
1989-08-01
Although few reports address the use of three-phase bone scanning (TPBS) and {sup 111}In-labeled white blood cell (In-WBC) scintigraphy in hip arthroplasty utilizing a porous coated prosthesis, the literature suggests that scintigraphic patterns in the uncomplicated patient may differ from that seen in the cemented prosthesis. In an attempt to determine the scintigraphic natural history, 25 uncomplicated porous coated hip arthroplasties in 21 patients were prospectively studied with serial TPBS and In-WBC at approximately 7 days, and at 3, 6, 12, 18, and 24 mo postoperatively. This report deals with findings related to the prosthetic tip. Only one of 136more » flow studies were abnormal and only two of 136 blood-pool images demonstrated focally increased activity. All 25 prostheses (120 of 143 scans) demonstrated increased uptake on the bone phase images. The area about the tip was divided into three segments; increased uptake at 24 mo was noted in the medial, distal, and lateral segments in 16%, 72%, and 56% of prostheses, respectively. Twenty of 25 prostheses (82 of 142 scans) showed uptake on In-WBC scintigraphy, being noted in 48% of prostheses at 24 mo. We conclude that scintigraphic patterns in the uncomplicated patient with a porous coated prosthesis appear to differ from patterns described in cemented prostheses.« less
Qu, Cunmin; Zhao, Huiyan; Fu, Fuyou; Wang, Zhen; Zhang, Kai; Zhou, Yan; Wang, Xin; Wang, Rui; Xu, Xinfu; Tang, Zhanglin; Lu, Kun; Li, Jia-Na
2016-01-01
Flavonoids, the compounds that impart color to fruits, flowers, and seeds, are the most widespread secondary metabolites in plants. However, a systematic analysis of these loci has not been performed in Brassicaceae. In this study, we isolated 649 nucleotide sequences related to flavonoid biosynthesis, i.e., the Transparent Testa (TT) genes, and their associated amino acid sequences in 17 Brassicaceae species, grouped into Arabidopsis or Brassicaceae subgroups. Moreover, 36 copies of 21 genes of the flavonoid biosynthesis pathway were identified in Arabidopsis thaliana, 53 were identified in Brassica rapa, 50 in Brassica oleracea, and 95 in B. napus, followed the genomic distribution, collinearity analysis and genes triplication of them among Brassicaceae species. The results showed that the extensive gene loss, whole genome triplication, and diploidization that occurred after divergence from the common ancestor. Using qRT-PCR methods, we analyzed the expression of 18 flavonoid biosynthesis genes in 6 yellow- and black-seeded B. napus inbred lines with different genetic background, found that 12 of which were preferentially expressed during seed development, whereas the remaining genes were expressed in all B. napus tissues examined. Moreover, 14 of these genes showed significant differences in expression level during seed development, and all but four of these (i.e., BnTT5, BnTT7, BnTT10, and BnTTG1) had similar expression patterns among the yellow- and black-seeded B. napus. Results showed that the structural genes (BnTT3, BnTT18, and BnBAN), regulatory genes (BnTTG2 and BnTT16) and three encoding transfer proteins (BnTT12, BnTT19, and BnAHA10) might play an crucial roles in the formation of different seed coat colors in B. napus. These data will be helpful for illustrating the molecular mechanisms of flavonoid biosynthesis in Brassicaceae species. PMID:27999578
Peñagaricano, Francisco; Zorrilla, Pilar; Naya, Hugo; Robello, Carlos; Urioste, Jorge I
2012-02-01
The white coat colour of sheep is an important economic trait. For unknown reasons, some animals are born with, and others develop with time, black skin spots that can also produce pigmented fibres. The presence of pigmented fibres in the white wool significantly decreases the fibre quality. The aim of this work was to study gene expression in black spots (with and without pigmented fibres) and white skin by microarray techniques, in order to identify the possible genes involved in the development of this trait. Five unrelated Corriedale sheep were used and, for each animal, the three possible comparisons (three different hybridisations) between the three samples of interest were performed. Differential gene expression patterns were analysed using different t-test approaches. Most of the major genes with well-known roles in skin pigmentation, e.g. ASIP, MC1R and C-KIT, showed no significant difference in the gene expression between white skin and black spots. On the other hand, many of the differentially expressed genes (raw P-value < 0.005) detected in this study, e.g. C-FOS, KLF4 and UFC1, fulfil biological functions that are plausible to be involved in the formation of black spots. The gene expression of C-FOS and KLF4, transcription factors involved in the cellular response to external factors such as ultraviolet light, was validated by quantitative polymerase chain reaction (PCR). This exploratory study provides a list of candidate genes that could be associated with the development of black skin spots that should be studied in more detail. Characterisation of these genes will enable us to discern the molecular mechanisms involved in the development of this feature and, hence, increase our understanding of melanocyte biology and skin pigmentation. In sheep, understanding this phenomenon is a first step towards developing molecular tools to assist in the selection against the presence of pigmented fibres in white wool.
Wang, Lu; Ruan, Yong-Ling
2012-10-01
Despite substantial evidence on the essential roles of cell wall invertase (CWIN) in seed filling, it remains largely unknown how CWIN exerts its regulation early in seed development, a critical stage that sets yield potential. To fill this knowledge gap, we systematically examined the spatial and temporal expression patterns of a major CWIN gene, GhCWIN1, in cotton (Gossypium hirsutum) seeds from prefertilization to prestorage phase. GhCWIN1 messenger RNA was abundant at the innermost seed coat cell layer at 5 d after anthesis but became undetectable at 10 d after anthesis, at the onset of its differentiation into transfer cells characterized by wall ingrowths, suggesting that CWIN may negatively regulate transfer cell differentiation. Within the filial tissues, GhCWIN1 transcript was detected in endosperm cells undergoing nuclear division but not in those cells at the cellularization stage, with similar results observed in Arabidopsis (Arabidopsis thaliana) endosperm for CWIN, AtCWIN4. These findings indicate a function of CWIN in nuclear division but not cell wall biosynthesis in endosperm, contrasting to the role proposed for sucrose synthase (Sus). Further analyses revealed a preferential expression pattern of GhCWIN1 and AtCWIN4 in the provascular region of the torpedo embryos in cotton and Arabidopsis seed, respectively, indicating a role of CWIN in vascular initiation. Together, these novel findings provide insights into the roles of CWIN in regulating early seed development spatially and temporally. By comparing with previous studies on Sus expression and in conjunction with the expression of other related genes, we propose models of CWIN- and Sus-mediated regulation of early seed development.
Controlled Patterning and Growth of Single Wall and Multi-wall Carbon Nanotubes
NASA Technical Reports Server (NTRS)
Delzeit, Lance D. (Inventor)
2005-01-01
Method and system for producing a selected pattern or array of at least one of a single wall nanotube and/or a multi-wall nanotube containing primarily carbon. A substrate is coated with a first layer (optional) of a first selected metal (e.g., Al and/or Ir) and with a second layer of a catalyst (e.g., Fe, Co, Ni and/or Mo), having selected first and second layer thicknesses provided by ion sputtering, arc discharge, laser ablation, evaporation or CVD. The first layer and/or the second layer may be formed in a desired non-uniform pattern, using a mask with suitable aperture(s), to promote growth of carbon nanotubes in a corresponding pattern. A selected heated feed gas (primarily CH4 or C2Hn with n=2 and/or 4) is passed over the coated substrate and forms primarily single wall nanotubes or multiple wall nanotubes, depending upon the selected feed gas and its temperature. Nanofibers, as well as single wall and multi-wall nanotubes, are produced using plasma-aided growth from the second (catalyst) layer. An overcoating of a selected metal or alloy can be deposited, over the second layer, to provide a coating for the carbon nanotubes grown in this manner.
Copper circuit patterning on polymer using selective surface modification and electroless plating
NASA Astrophysics Data System (ADS)
Park, Sang Jin; Ko, Tae-Jun; Yoon, Juil; Moon, Myoung-Woon; Oh, Kyu Hwan; Han, Jun Hyun
2017-02-01
We have examined a potential new and simple method for patterning a copper circuit on PET substrate by copper electroless plating, without the pretreatment steps (i.e., sensitization and activation) for electroless plating as well as the etching processes of conventional circuit patterning. A patterned mask coated with a catalyst material, Ag, for the reduction of Cu ions, is placed on a PET substrate. Subsequent oxygen plasma treatment of the PET substrate covered with the mask promotes the selective generation of anisotropic pillar- or hair-like nanostructures coated with co-deposited nanoparticles of the catalyst material on PET. After oxygen plasma treatment, a Cu circuit is well formed just by dipping the plasma-treated PET into a Cu electroless plating solution. By increasing the oxygen gas pressure in the chamber, the height of the nanostructures increases and the Ag catalyst particles are coated on not only the top but also the side surfaces of the nanostructures. Strong mechanical interlocking between the Cu circuit and PET substrate is produced by the large surface area of the nanostructures, and enhances peel strength. Results indicate this new simple two step (plasma surface modification and pretreatment-free electroless plating) method can be used to produce a flexible Cu circuit with good adhesion.
Laser etching of polymer masked leadframes
NASA Astrophysics Data System (ADS)
Ho, C. K.; Man, H. C.; Yue, T. M.; Yuen, C. W.
1997-02-01
A typical electroplating production line for the deposition of silver pattern on copper leadframes in the semiconductor industry involves twenty to twenty five steps of cleaning, pickling, plating, stripping etc. This complex production process occupies large floor space and has also a number of problems such as difficulty in the production of rubber masks and alignment, generation of toxic fumes, high cost of water consumption and sometimes uncertainty on the cleanliness of the surfaces to be plated. A novel laser patterning process is proposed in this paper which can replace many steps in the existing electroplating line. The proposed process involves the application of high speed laser etching techniques on leadframes which were protected with polymer coating. The desired pattern for silver electroplating is produced by laser ablation of the polymer coating. Excimer laser was found to be most effective for this process as it can expose a pattern of clean copper substrate which can be silver plated successfully. Previous working of Nd:YAG laser ablation showed that 1.06 μm radiation was not suitable for this etching process because a thin organic and transparent film remained on the laser etched region. The effect of excimer pulse frequency and energy density upon the removal rate of the polymer coating was studied.
Li, Bo-Chao; Chang, Hao; Ren, Ke-Feng; Ji, Jian
2016-11-01
Substrate-mediated delivery of functional plasmid DNA (pDNA) has been proven to be a promising strategy to promote competitiveness of endothelial cells (ECs) over smooth muscle cells (SMCs), which is beneficial to inducing fast endothelialization of implanted vascular devices. Thus, it is of great importance to develop universal approaches with simplicity and easiness to immobilize DNA complex nanoparticles on substrates. In this study, the bioinspired polydopamine (PDA) coating was employed in immobilization of DNA complex nanoparticles, which were composed of protamine (PrS) and plasmid DNA encoding with hepatocyte growth factor (HGF-pDNA) gene. We demonstrated that the DNA complex nanoparticles can be successfully immobilized onto the PDA surface. Consequently, the HGF expression of both ECs and SMCs were significantly improved when they cultured on the DNA complex nanoparticles-immobilized substrates. Furthermore, EC proliferation was specifically promoted due to bioactivity of HGF, leading to an enhancement of EC competitiveness over SMCs. Our findings demonstrated the substrate-mediated functional gene nanoparticle delivery through PDA coating as a simple and efficient approach. It may hold great potential in the field of interventional cardiovascular implants. Copyright © 2016 Elsevier B.V. All rights reserved.
Ma, Yansong; Tian, Long; Li, Xinxiu; Li, Ying-Hui; Guan, Rongxia; Guo, Yong; Qiu, Li-Juan
2016-01-01
Soybean seed coat exists in a range of colors from yellow, green, brown, black, to bicolor. Classical genetic analysis suggested that soybean seed color was a moderately complex trait controlled by multi-loci. However, only a couple of loci could be detected using a single biparental segregating population. In this study, a combination of association mapping and bulk segregation analysis was employed to identify genes/loci governing this trait in soybean. A total of 14 loci, including nine novel and five previously reported ones, were identified using 176,065 coding SNPs selected from entire SNP dataset among 56 soybean accessions. Four of these loci were confirmed and further mapped using a biparental population developed from the cross between ZP95-5383 (yellow seed color) and NY279 (brown seed color), in which different seed coat colors were further dissected into simple trait pairs (green/yellow, green/black, green/brown, yellow/black, yellow/brown, and black/brown) by continuously developing residual heterozygous lines. By genotyping entire F2 population using flanking markers located in fine-mapping regions, the genetic basis of seed coat color was fully dissected and these four loci could explain all variations of seed colors in this population. These findings will be useful for map-based cloning of genes as well as marker-assisted breeding in soybean. This work also provides an alternative strategy for systematically isolating genes controlling relative complex trait by association analysis followed by biparental mapping. PMID:27404272
Graeber, Kai; Linkies, Ada; Steinbrecher, Tina; Mummenhoff, Klaus; Tarkowská, Danuše; Turečková, Veronika; Ignatz, Michael; Sperber, Katja; Voegele, Antje; de Jong, Hans; Urbanová, Terezie; Strnad, Miroslav; Leubner-Metzger, Gerhard
2014-01-01
Seed germination is an important life-cycle transition because it determines subsequent plant survival and reproductive success. To detect optimal spatiotemporal conditions for germination, seeds act as sophisticated environmental sensors integrating information such as ambient temperature. Here we show that the DELAY OF GERMINATION 1 (DOG1) gene, known for providing dormancy adaptation to distinct environments, determines the optimal temperature for seed germination. By reciprocal gene-swapping experiments between Brassicaceae species we show that the DOG1-mediated dormancy mechanism is conserved. Biomechanical analyses show that this mechanism regulates the material properties of the endosperm, a seed tissue layer acting as germination barrier to control coat dormancy. We found that DOG1 inhibits the expression of gibberellin (GA)-regulated genes encoding cell-wall remodeling proteins in a temperature-dependent manner. Furthermore we demonstrate that DOG1 causes temperature-dependent alterations in the seed GA metabolism. These alterations in hormone metabolism are brought about by the temperature-dependent differential expression of genes encoding key enzymes of the GA biosynthetic pathway. These effects of DOG1 lead to a temperature-dependent control of endosperm weakening and determine the optimal temperature for germination. The conserved DOG1-mediated coat-dormancy mechanism provides a highly adaptable temperature-sensing mechanism to control the timing of germination. PMID:25114251
Atomic Layer Deposition for the Modification and Creation of Nanomaterials
NASA Astrophysics Data System (ADS)
Needham, Erinn Christine
Atomic layer deposition (ALD) is a vapor-phase technique for the conformal deposition of material with sub-nanometer precision, making it an ideal process for modifying and even creating nanomaterials. The focus of this dissertation is the study of how ALD precursors interact with organic materials, namely polymers, to create selectively deposited nano-scale patterns and how ALD coatings modify biological responses to nanomaterials, namely carbon nanotubes (CNT), after inhalation. Nanoscale patterning is vital to the semiconductor industry. With features becoming smaller and more complex with each passing year, new techniques are required to meet the needs of the industry. The ability to selectively pattern a material onto a wafer is of particular interest for the replacement of costly etching steps. In the first half of this dissertation, a method for the selective deposition of nano-scale patterns is presented. Patterned polymers were used as sacrificial sponges to soak up ALD precursors for the creation of metal-oxide features. Meanwhile, deposition in areas without polymer was limited to the monolayer regime. Following infiltration, the saturated polymer was burned away and the precursor oxidized to form a metal oxide reproduction of the polymer pattern. Determining the reaction between the ALD precursor, trimethylaluminum, and polymer, poly(methyl methacrylate), helped to achieve patterning by informing the proper selection of reactor temperature as well as exposure and purge times. Using this technique, features from tens of nanometers to tens of microns were patterned uniformly and simultaneously across a 150 mm wafer. Finally, this technique was extended to pattern two different materials using only one patterned polymer layer. ALD was first used to deposit a metal oxide were there was no polymer. By selecting ALD precursors that do not react within or on top of the polymer, selective deposition of the first material was achieved. Following this, the polymer was infiltrated as before to selectively deposit the second material. By patterning two materials from one patterned polymer, no pattern alignment between materials is necessary. The reaction mechanism determined for this system can be applied and expanded to other vapor-phase metal-organic interactions with polymers. The ability to make and align nanoscale features is critically important for manufacturing improved semiconductor devices. The second half of this dissertation focuses on how modification of CNT affects biological response in a material-dependent manner. CNT have unique physical and chemical properties that lead to applications in many areas including: electronics, high-strength materials, filtration and drug delivery. By surface-modifying these materials, a whole new realm of applications appears. Despite the benefits these coatings may provide (e.g., photocatalytic properties and increased conductivity) they can also alter the toxicological response to MWCNT. In rodent models, the inhalation of MWCNT can lead to inflammation and fibrosis. Here, we observed that ZnO coatings on MWCNT led to an acute inflammatory response but did not change the fibrotic response in mice following inhalation. The contribution of ZnO coating dissolution was still unknown following the in vivo study with mice. Alumina, ZnO and aluminum-doped ZnO (AZO) coatings on MWCNT were studied in vitro using various cell lines to determine the contribution of ions to toxicity. AZO is less soluble than ZnO and composed only of previously-characterized materials. We discovered that the concentration of Zn2+ in solution correlated with levels of cytotoxicity in vitro and differences in dissolution between AZO and ZnO coatings led to differences in pro-inflammatory cytokine release. This knowledge can assist with the toxicological assessment of other pure and composite nanomaterials and lead to the creation of safer nanomaterials.
Low thermal distortion extreme-UV lithography reticle
Gianoulakis, Steven E.; Ray-Chaudhuri, Avijit K.
2002-01-01
Thermal distortion of reticles or masks can be significantly reduced by emissivity engineering, i.e., the selective placement or omission of coatings on the reticle. Reflective reticles so fabricated exhibit enhanced heat transfer thereby reducing the level of thermal distortion and ultimately improving the quality of the transcription of the reticle pattern onto the wafer. Reflective reticles include a substrate having an active region that defines the mask pattern and non-active region(s) that are characterized by a surface that has a higher emissivity than that of the active region. The non-active regions are not coated with the radiation reflective material.
Low thermal distortion extreme-UV lithography reticle
Gianoulakis, Steven E.; Ray-Chaudhuri, Avijit K.
2001-01-01
Thermal distortion of reticles or masks can be significantly reduced by emissivity engineering, i.e., the selective placement or omission of coatings on the reticle. Reflective reticles so fabricated exhibit enhanced heat transfer thereby reducing the level of thermal distortion and ultimately improving the quality of the transcription of the reticle pattern onto the wafer. Reflective reticles include a substrate having an active region that defines the mask pattern and non-active region(s) that are characterized by a surface that has a higher emissivity than that of the active region. The non-active regions are not coated with the radiation reflective material.
Cell and module formation research area
NASA Technical Reports Server (NTRS)
Bickler, D. B.
1982-01-01
Metallization is discussed. The influence of hydrogen on the firing of base-metal pastes in reducing atmospheres is reported. A method for optimization of metallization patterns is presented. A process sequence involving an AR coating and thick-film metallization system capable of penetrating the AR coating during firing is reported. Design and construction of the NMA implantation machine is reported. Implanted back-surface fields and NMA primary (front) junctions are discussed. The use of glass beads, a wave-soldering device, and ion milling is reported. Processing through the module fabrication and environmental testing of its design are reported. Metallization patterns by mathematical optimization are assessed.
Sun, Jing; Zhou, Wenhui; Yang, Haibo; Zhen, Xue; Ma, Longfei; Williams, Dirk; Sun, Xudong; Lang, Ming-Fei
2018-05-10
The development of flexible and transparent devices requires completely transparent and flexible circuits (TFCs). To overcome the disadvantages of the previously reported TFCs that are partially transparent, lacking pattern control, or labor consuming, we achieve true TFCs via a facile process with precise pattern control, exhibiting concurrent high transparency, conductivity, flexibility, stretchability, and robustness. A highly transparent and flexible conductive film is first made through spin coating silver nanowires (AgNWs) onto polydimethylsiloxane (PDMS), and demonstrates simultaneous high transparency (90.86%) and low sheet resistance (3.22 Ω sq-1). Taking advantage of microfluidic technology, circuits with ultraprecise and complex patterns from the microscale to milliscale are obtained through spin coating of AgNWs into microfluidic channels on PDMS. Without elaborate processing, this method may be suitable for mass production, which would contribute enormously to potential applications in wearable medical equipment and transparent electronic devices.
Razmjou, Amir; Asadnia, Mohsen; Ghaebi, Omid; Yang, Hao-Cheng; Ebrahimi Warkiani, Majid; Hou, Jingwei; Chen, Vicki
2017-11-01
In this work, spatial patterning of a thin, dense, zeolitic imidazolate framework (ZIF-8) pattern was generated using photolithography and nanoscale (60 nm) dopamine coating. A bioinspired, unique, reversible, two-color iridescent pattern can be easily obtained for potential applications in sensing and photonics.
Gold coated metal nanostructures grown by glancing angle deposition and pulsed electroplating
NASA Astrophysics Data System (ADS)
Grüner, Christoph; Reeck, Pascal; Jacobs, Paul-Philipp; Liedtke, Susann; Lotnyk, Andriy; Rauschenbach, Bernd
2018-05-01
Nickel based nanostructures are grown by glancing angle deposition (GLAD) on flat and pre-patterned substrates. These fabricated porous thin films were subsequently coated by pulsed electroplating with gold. The morphology and conformity of the gold coating were investigated by scanning electron microscopy and X-ray diffraction. Controlled growth of closed gold layers on the nanostructures could be achieved, while the open-pore structure of the nanosculptured thin films was preserved. Such gold coated nanostructures are a candidate for optical sensing and catalysis applications. The demonstrated method can be applied for numerous material combinations, allowing to provide GLAD thin films with new surface properties.
TiC-Fe-Based Composite Coating Prepared by Self-Propagating High-Temperature Synthesis
NASA Astrophysics Data System (ADS)
He, Shen; Fan, Xi'an; Chang, Qingming; Xiao, Lixiang
2017-06-01
TiC-Fe-based composite coatings were prepared in situ by self-propagating high-temperature synthesis combined with vacuum expendable pattern casting process. The band-like TiC phase embedded in a continuous Fe binder. There were no obvious defects and impurities at the interface between coatings and matrices. Fe presented consecutively in the coating zones and substrate zones without interruption and the microhardness in the cross-sectional area of the coating-matrix reduces continuously from the coating to the matrix area, indicating a good metallurgical bonding between the coatings and matrices. The effect of casting temperature on the microstructure and hardness of TiC-Fe-based composite coating was investigated in detail. The TiC particles formed at low casting temperature were nearly spherical in shape, and the size of TiC particles increased with increasing casting temperature due to more agglomeration. The hardness of the coatings increased first and then decreased with increasing casting temperature, and reached the highest value of 68 HRC when the casting temperature was 1773 K (1500 °C), which was twice more than that of the matrix.
Microstructure and Mechanical Properties of Zn-Ni-Al₂O₃ Composite Coatings.
Bai, Yang; Wang, Zhenhua; Li, Xiangbo; Huang, Guosheng; Li, Caixia; Li, Yan
2018-05-21
Zn-Ni-Al₂O₃ composite coatings with different Ni contents were fabricated by low-pressure cold spray (LPCS) technology. The effects of the Ni content on the microstructural and mechanical properties of the coatings were investigated. According to X-ray diffraction patterns, the composite coatings were primarily composed of metallic-phase Zn and Ni and ceramic-phase Al₂O₃. The energy-dispersive spectroscopy results show that the Al₂O₃ content of the composite coatings gradually decreased with increasing of Ni content. The cross-sectional morphology revealed thick, dense coatings with a wave-like stacking structure. The process of depositing Zn and Ni particles and Al₂O₃ particles by the LPCS method was examined, and the deposition mechanism was demonstrated to be mechanical interlocking. The bond strength, micro hardness and friction coefficient of the coatings did not obviously change when the Ni content varied. The presence of Al₂O₃ and Ni increased the wear resistance of the composite coatings, which was higher than that of pure Zn coatings, and the wear mechanism was abrasive and adhesive wear.
NASA Astrophysics Data System (ADS)
Inbaraj, Baskaran Stephen; Tsai, Tsung-Yu; Chen, Bing-Huei
2012-02-01
Iron oxide nanoparticles (IONPs) were synthesized by coprecipitation of iron salts in alkali media followed by coating with glycol chitosan (GC-coated IONPs). Both bare and GC-coated IONPs were subsequently characterized and evaluated for their antibacterial activity. Comparison of Fourier transform infrared spectra and thermogravimetric data of bare and GC-coated IONPs confirmed the presence of GC coating on IONPs. Magnetization curves showed that both bare and GC-coated IONPs are superparamagnetic and have saturation magnetizations of 70.3 and 59.8 emu g-1, respectively. The IONP size was measured as ~8-9 nm by transmission electron microscopy, and their crystal structure was assigned to magnetite from x-ray diffraction patterns. Both bare and GC-coated IONPs inhibited the growths of Escherichia coli ATCC 8739 and Salmonella enteritidis SE 01 bacteria better than the antibiotics linezolid and cefaclor, as evaluated by the agar dilution assay. GC-coated IONPs showed higher potency against E. coli O157:H7 and Staphylococcus aureus ATCC 10832 than bare IONPs. Given their biocompatibility and antibacterial properties, GC-coated IONPs are a potential nanomaterial for in vivo applications.
Zhuang, Junjun; Lin, Suya; Dong, Lingqing; Cheng, Kui; Weng, Wenjian
2018-04-15
Mechanical stimuli at the bone-implant interface are considered to activate the mechanotransduction pathway of the cell to improve the initial osseointegration establishment and to guarantee clinical success of the implant. However, control of the mechanical stimuli at the bone-implant interface still remains a challenge. In this study, we have designed a strategy of a magnetically responsive coating on which the mechanical stimuli is controlled because of coating deformation under static magnetic field (SMF). The iron oxide nanoparticle/mineralized collagen (IOP-MC) coatings were electrochemically codeposited on titanium substrates in different quantities of IOPs and distributions; the resulting coatings were verified to possess swelling behavior with flexibility same as that of hydrogel. The relative quantity of IOP to collagen and the IOP distribution in the coatings were demonstrated to play a critical role in mediating cell behavior. The cells present on the outer layer of the distributed IOP-MC (O-IOP-MC) coating with a mass ratio of 0.67 revealed the most distinct osteogenic differentiation activity being promoted, which could be attributed to the maximized mechanical stimuli with exposure to SMF. Furthermore, the enhanced osteogenic differentiation of the stimulated MC3T3-E1 cells originated from magnetically actuated mechanotransduction signaling pathway, embodying the upregulated expression of osteogenic-related and mechanotransduction-related genes. This work therefore provides a promising strategy for implementing mechanical stimuli to activate mechanotransduction on the bone-implant interface and thus to promote osseointegration. The magnetically actuated coating is designed to produce mechanical stimuli to cells for promoting osteogenic differentiation based on the coating deformation. Iron oxide nanoparticles (IOPs) were incorporated into the mineralized collagen coatings (MC) forming the composite coatings (IOP-MC) with spatially distributed IOPs, and the IOP-MC coatings with outer distributed IOPs (O-IOPs-MC) shows the maximized mechanical stimuli to cells with enhanced osteogenic differentiation under static magnetic field. The upregulated expression of the associated genes reveals that the enabled mechanotransduction signaling pathway is responsible for the promoted cellular osteogenic differentiation. This work therefore provides a promising strategy for implementing mechanical stimuli to activate mechanotransduction on the bone-implant interface to promote osseointegration. Copyright © 2018 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.
Cerebroretinal microangiopathy with calcifications and cysts associated with CTC1 and NDP mutations.
Romaniello, Romina; Arrigoni, Filippo; Citterio, Andrea; Tonelli, Alessandra; Sforzini, Cinzia; Rizzari, Carmelo; Pessina, Marco; Triulzi, Fabio; Bassi, Maria Teresa; Borgatti, Renato
2013-12-01
Mutations in the conserved telomere maintenance component 1 (CTC1) gene were recently described in Coats plus syndrome and in cerebroretinal microangiopathy with calcifications and cysts. Norrie disease protein (NDP) gene was found mutated in Norrie disease, in Familial Exudative Vitreoretinopathy, and in Coats syndrome. Here we describe a boy affected by Norrie disease who developed typical features of cerebroretinal microangiopathy with calcifications and cysts. Direct sequencing of the CTC1 and NDP genes in this patient shows the presence of compound heterozygosity for 2 mutations in CTC1 (c.775G>A, pV259M and a novel microdeletion c.1213delG) and a missense mutation in the NDP gene (c.182T>C, p.L61P). Based on these genetic findings and on the expression of both genes in endothelial cells, we postulate that microangiopathy might be a primary underlying pathologic abnormality in cerebroretinal microangiopathy with calcifications and cysts. This hypothesis is further supported by magnetic resonance imaging (MRI) data showing multiple minute calcifications in the deep gray nuclei and in terminal arteriolar zones.
Schaible, H G; Freudenberger, U; Neugebauer, V; Stiller, R U
1994-10-01
This study addressed the intraspinal release of immunoreactive calcitonin gene-related peptide in vivo during mechanical stimulation of the normal joint and during the development of an acute experimental inflammation in the knee joint in the anaesthetized cat (spinalized) and rat (not spinalized). Release was assessed using microprobes coated with antibody to calcitonin gene-related peptide; inhibition of binding of [125I]calcitonin gene-related peptide to these probes following insertion into the spinal cord is equated with intraspinal release of the endogenous (unlabelled) peptide. Probes inserted prior to inflammation showed marked basal release of immunoreactive calcitonin gene-related peptide in the dorsal horn with a maximum in the superficial dorsal horn in the absence of intentional stimulation. The pattern of binding of [125I]calcitonin gene-related peptide was not or only minimally changed by innocuous mechanical stimuli (flexion of and innocuous pressure to the knee in the cat and innocuous pressure to the knee of the rat) but was significantly altered by electrical stimulation of the tibial nerve in the cat (sufficient to excite unmyelinated afferent fibres), indicating release of the peptide by the latter stimulus. During the first hours of the development of an experimental inflammation in the knee joint induced by intra-articular injections of kaolin and carrageenan, the pattern of binding of [125I]calcitonin gene-related peptide changed. In the cat, the level of immunoreactive calcitonin gene-related peptide showed a persistent increase in the gray matter and up to the surface of the cord and release was slightly increased by innocuous stimuli. In the rat, increased levels of immunoreactive calcitonin gene-related peptide were mainly seen in the superficial and deep dorsal horn during innocuous pressure (this stimulus did not evoke release of the peptide prior to inflammation) and noxious pressure applied to the injected knee, whereas increased basal levels were only observed at later stages. These data show that the development of an acute experimental inflammation in the joint is associated with an enhancement of the intraspinal release of immunoreactive calcitonin gene-related peptide. Since the changes in the release were noted at an early stage, within the first hours, they could contribute to the generation of inflammation-evoked changes of the responsiveness of spinal cord neurons and hence to the mechanisms inducing inflammatory pain.
San Juan, Aurélie; Bala, Madiha; Hlawaty, Hanna; Portes, Patrick; Vranckx, Roger; Feldman, Laurent J; Letourneur, Didier
2009-11-09
In patients receiving drug eluting stents, there is a growing concern about both the long-term toxicity/degradability of the polymers used for the coating, and the nature of the therapeutic agents. We hypothesized that the use of a functionalized biocompatible polymer for a stent coating could be appropriate for local arterial therapy. A cationized pullulan hydrogel was thus prepared to cover bare metal stents that could be further loaded with small interfering RNA (siRNA) targeted at MMP2 for gene silencing in vascular cells. The efficient coverage of the stent struts by a smooth polymeric layer, which can withstand the crimping of the stent on a balloon-catheter and its deployment, was demonstrated by fluorescence microscopy, scanning electron microscopy, and atomic force microscopy. The release of siRNA from the stents was modulated by the presence of the cationic groups, as compared to noncationized pullulan hydrogel. In vivo implantation of coated stents was successful and cationized pullulan-based hydrogels loaded with siRNA in rabbit balloon-injured carotid arteries induced an uptake of siRNA into the arterial wall and a decrease of pro-MMP2 activity. These results suggest that cationized pullulan-based hydrogel could be used as a new biocompatible and biodegradable stent coating for local gene therapy in the arterial wall.
Determination of the Gene Sequence of Poliovirus with Pactamycin
Summers, D. F.; Maizel, J. V.
1971-01-01
By examination of the virus-specific polypeptides formed after the addition of pactamycin, an inhibitor of protein chain initiation, to infected cells, it has been possible to tentatively locate the virus coat proteins at the amino terminus of the large, virus-specific protein precursor, and, therefore, to assign the coat protein cistron to the 5′ end of the RNA. PMID:4330946
Johnson, Jeremiah G; Murphy, Caitlin N; Sippy, Jean; Johnson, Tylor J; Clegg, Steven
2011-07-01
Klebsiella pneumoniae is an opportunistic pathogen which frequently causes hospital-acquired urinary and respiratory tract infections. K. pneumoniae may establish these infections in vivo following adherence, using the type 3 fimbriae, to indwelling devices coated with extracellular matrix components. Using a colony immunoblot screen, we identified transposon insertion mutants which were deficient for type 3 fimbrial surface production. One of these mutants possessed a transposon insertion within a gene, designated mrkI, encoding a putative transcriptional regulator. A site-directed mutant of this gene was constructed and shown to be deficient for fimbrial surface expression under aerobic conditions. MrkI mutants have a significantly decreased ability to form biofilms on both abiotic and extracellular matrix-coated surfaces. This gene was found to be cotranscribed with a gene predicted to encode a PilZ domain-containing protein, designated MrkH. This protein was found to bind cyclic-di-GMP (c-di-GMP) and regulate type 3 fimbrial expression.
Johnson, Jeremiah G.; Murphy, Caitlin N.; Sippy, Jean; Johnson, Tylor J.; Clegg, Steven
2011-01-01
Klebsiella pneumoniae is an opportunistic pathogen which frequently causes hospital-acquired urinary and respiratory tract infections. K. pneumoniae may establish these infections in vivo following adherence, using the type 3 fimbriae, to indwelling devices coated with extracellular matrix components. Using a colony immunoblot screen, we identified transposon insertion mutants which were deficient for type 3 fimbrial surface production. One of these mutants possessed a transposon insertion within a gene, designated mrkI, encoding a putative transcriptional regulator. A site-directed mutant of this gene was constructed and shown to be deficient for fimbrial surface expression under aerobic conditions. MrkI mutants have a significantly decreased ability to form biofilms on both abiotic and extracellular matrix-coated surfaces. This gene was found to be cotranscribed with a gene predicted to encode a PilZ domain-containing protein, designated MrkH. This protein was found to bind cyclic-di-GMP (c-di-GMP) and regulate type 3 fimbrial expression. PMID:21571997
Lepre, Jorge; Rice, J Jeremy; Tu, Yuhai; Stolovitzky, Gustavo
2004-05-01
Despite the growing literature devoted to finding differentially expressed genes in assays probing different tissues types, little attention has been paid to the combinatorial nature of feature selection inherent to large, high-dimensional gene expression datasets. New flexible data analysis approaches capable of searching relevant subgroups of genes and experiments are needed to understand multivariate associations of gene expression patterns with observed phenotypes. We present in detail a deterministic algorithm to discover patterns of multivariate gene associations in gene expression data. The patterns discovered are differential with respect to a control dataset. The algorithm is exhaustive and efficient, reporting all existent patterns that fit a given input parameter set while avoiding enumeration of the entire pattern space. The value of the pattern discovery approach is demonstrated by finding a set of genes that differentiate between two types of lymphoma. Moreover, these genes are found to behave consistently in an independent dataset produced in a different laboratory using different arrays, thus validating the genes selected using our algorithm. We show that the genes deemed significant in terms of their multivariate statistics will be missed using other methods. Our set of pattern discovery algorithms including a user interface is distributed as a package called Genes@Work. This package is freely available to non-commercial users and can be downloaded from our website (http://www.research.ibm.com/FunGen).
Plasma-Etching of Spray-Coated Single-Walled Carbon Nanotube Films for Biointerfaces
NASA Astrophysics Data System (ADS)
Kim, Joon Hyub; Lee, Jun-Yong; Min, Nam Ki
2012-08-01
We present an effective method for the batch fabrication of miniaturized single-walled carbon nanotube (SWCNT) film electrodes using oxygen plasma etching. We adopted the approach of spray-coating for good adhesion of the SWCNT film onto a pre-patterned Pt support and used O2 plasma patterning of the coated films to realize efficient biointerfaces between SWCNT surfaces and biomolecules. By these approaches, the SWCNT film can be easily integrated into miniaturized electrode systems. To demonstrate the effectiveness of plasma-etched SWCNT film electrodes as biointerfaces, Legionella antibody was selected as analysis model owing to its considerable importance to electrochemical biosensors and was detected using plasma-etched SWCNT film electrodes and a 3,3',5,5'-tetramethyl-benzidine dihydrochloride/horseradish peroxidase (TMB/HRP) catalytic system. The response currents increased with increasing concentration of Legionella antibody. This result indicates that antibodies were effectively immobilized on plasma-etched and activated SWCNT surfaces.
Liu, Hui; Gao, Shou-Wei; Cai, Jing-Sheng; He, Cheng-Lin; Mao, Jia-Jun; Zhu, Tian-Xue; Chen, Zhong; Huang, Jian-Ying; Meng, Kai; Zhang, Ke-Qin; Al-Deyab, Salem S.; Lai, Yue-Kun
2016-01-01
Multifuntional fabrics with special wettability have attracted a lot of interest in both fundamental research and industry applications over the last two decades. In this review, recent progress of various kinds of approaches and strategies to construct super-antiwetting coating on cellulose-based substrates (fabrics and paper) has been discussed in detail. We focus on the significant applications related to artificial superhydrophobic fabrics with special wettability and controllable adhesion, e.g., oil-water separation, self-cleaning, asymmetric/anisotropic wetting for microfluidic manipulation, air/liquid directional gating, and micro-template for patterning. In addition to the anti-wetting properties and promising applications, particular attention is paid to coating durability and other incorporated functionalities, e.g., air permeability, UV-shielding, photocatalytic self-cleaning, self-healing and patterned antiwetting properties. Finally, the existing difficulties and future prospects of this traditional and developing field are briefly proposed and discussed. PMID:28773253
Chowdhury, E H; Akaike, Toshihiro
2005-05-20
The DNA delivery to mammalian cells is an essential tool for analyzing gene structure, regulation, and function. The approach holds great promise for the further development of gene therapy techniques and DNA vaccination strategies to treat and control diseases. Here, we report on the establishment of a cell-specific gene delivery and expression system by physical adsorption of a cell-recognition molecule on the nano-crystal surface of carbonate apatite. As a model, DNA/nano-particles were successfully coated with asialofetuin to facilitate uptake by hepatocyte-derived cell lines through the asialoglycoprotein receptor (ASGPr) and albumin to prevent non-specific interactions of the particles with cell-surface. The resulting composite particles with dual surface properties could accelerate DNA uptake and enhance expression to a notable extent. Nano-particles coated with transferrin in the same manner dramatically enhanced transgene expression in the corresponding receptor-bearing cells and thus our newly developed strategy represents a universal phenomenon for anchoring a bio-recognition macromolecule on the apatite crystal surface for targeted gene delivery, having immediate applications in basic research laboratories and great promise for gene therapy. (c) 2005 Wiley Periodicals, Inc.
How the Leopard Gets Its Spots.
ERIC Educational Resources Information Center
Murray, James D.
1988-01-01
Discusses a single pattern formation mechanism that could underlie the wide variety of animal coat markings found in nature. Presents the results of a mathematical model for how these patterns may be generated in the course of embryonic development. (CW)
NASA Astrophysics Data System (ADS)
Sessions, John W.; Lindstrom, Dallin L.; Hanks, Brad W.; Hope, Sandra; Jensen, Brian D.
2016-04-01
Connecting technology to biologic discovery is a core focus of non-viral gene therapy biotechnologies. One approach that leverages both the physical and electrical function of microelectromechanical systems (MEMS) in cellular engineering is a technology previously described as lance array nanoinjection (LAN). In brief, LAN consists of a silicon chip measuring 2 cm by 2 cm that has been etched to contain an array of 10 μm tall, solid lances that are spaced every 10 μm in a grid pattern. This array of lances is used to physically penetrate hundreds of thousands of cells simultaneously and to then electrically deliver molecular loads into cells. In this present work, two variables related to the microfabrication of the silicon lances, namely lance geometry and coating, are investigated. The purpose of both experimental variables is to assess these parameters’ effect on propidium iodide (PI), a cell membrane impermeable dye, uptake to injected HeLa 229 cells. For the lance geometry experimentation, three different microfabricated lance geometries were used which include a flat/narrow (FN, 1 μm diameter), flat/wide (FW, 2-2.5 μm diameter), and pointed (P, 1 μm diameter) lance geometries. From these tests, it was shown that the FN lances had a slightly better cell viability rate of 91.73% and that the P lances had the best PI uptake rate of 75.08%. For the lance coating experimentation, two different lances were fabricated, both silicon etched lances with some being carbon coated (CC) in a <100 nm layer of carbon and the other lances being non-coated (Si). Results from this experiment showed no significant difference between lance types at three different nanoinjection protocols (0V, +1.5V DC, and +5V Pulsed) for both cell viability and PI uptake rates. One exception to this is the comparison of CC/5V Pul and Si/5V Pul samples, where the CC/5V Pul samples had a cell viability rate 5% higher. Both outcomes were unexpected and reveal how to better optimize LAN parameters for future transfection experimentation.
A biodegradable, immunoprotective, dual nanoporous capsule for cell-based therapies.
Zhang, Xulang; He, Hongyan; Yen, Chi; Ho, Wiston; Lee, L James
2008-11-01
To demonstrate the transplantation of drug-secreting cells with immunoprotection, a biodegradable delivery device combining two nanoporous capsules is developed using secretory alkaline phosphatase gene (SEAP) transfected mouse embryonic stem (mES) cells as a model system. The outer capsule is a poly (ethylene glycol) (PEG)-coated poly (epsilon-caprolactone) (PCL) chamber covered with a PEG grafted PCL nanoporous membrane made by phase inversion technique. SEAP gene transfected mES cells encapsulated in alginate-poly-L-lysine (AP) microcapsules are placed in the PCL capsule. Both nanoporous capsules showed good immunoprotection in the IgG solution. In microcapsules, mES cells could form a spheroid embryonic body (EB) and grow close to the microcapsule size. The secreted SEAP from encapsulated mES cells increased gradually to a maximum value before reaching a steady level, following the cell growth pattern in the microcapsule. Without microcapsules, mES cells only formed a monolayer in the large PCL capsule. The secreted SEAP release was very low. The integrated device showed a similar cell growth pattern to that in microcapsules alone, while the SEAP release rate could be regulated by the pore size of the large capsule. This integrated device can achieve multi-functionalities for cell-based therapy, i.e. a 3-D microenvironment provided by microcapsules for cell growth, superior immunoprotection and controllable release performance provided by the two nanoporous membranes, and good fibrosis prevention by PEG surface modification of the large capsule.
Murakami, Asuka; Arimoto, Takafumi; Suzuki, Dai; Iwai-Yoshida, Misato; Otsuka, Fukunaga; Shibata, Yo; Igarashi, Takeshi; Kamijo, Ryutaro; Miyazaki, Takashi
2012-04-01
Hydroxyapatite (HA)-coated titanium (Ti) is commonly used for implantable medical devices. This study examined in vitro osteoblast gene expression and antimicrobial activity against early and late colonizers of supra-gingival plaque on nanoscale HA-coated Ti prepared by discharge in a physiological buffered solution. The HA-coated Ti surface showed super-hydrophilicity, whereas the densely sintered HA and Ti surfaces alone showed lower hydrophilicity. The sintered HA and HA-coated Ti surfaces enhanced osteoblast phenotypes in comparison with the bare Ti surface. The HA-coated Ti enabled antimicrobial activity against early colonizers of supra-gingival plaques, namely Streptococcus mitis and Streptococcus gordonii. Such antimicrobial activity may be caused by the surface hydrophilicity, thereby leading to a repulsion force between the HA-coated Ti surface and the bacterial cell membranes. On the contrary, the sintered HA sample was susceptible to infection of microorganisms. Thus, hydrophilic-modified HA-coated Ti may have potential for use in implantable medical devices. From the Clinical Editor: This study establishes that Hydroxyapatite (HA)-coated titanium (Ti) surface of implanted devices may result in an optimal microenvironment to control and prevent infections and may have potential future clinical applications. Copyright © 2012 Elsevier Inc. All rights reserved.
NASA Astrophysics Data System (ADS)
Trivedi, Pramanshu; gupta, Pallavi; Srivastava, Swati; Jayaganthan, R.; Chandra, Ramesh; Roy, Partha
2014-02-01
Amongst the Ti alloys used as orthopedic implant materials, Ti6Al4V is one of the widely used alloys. Magnetron sputtering was used to deposit nanocomposite coating of Ti-Si-N on the Ti6Al4V substrate at different power and then the coating structure and surface properties were characterized through contact angle measurement, X-ray diffraction (XRD), scanning electron microscopy (SEM), and atomic force microscopy (AFM). In vitro biocompatibility of the coatings was assessed by using mouse bone marrow mesenchymal stem cells (mBMMSC). Antibacterial studies were performed using Escherichia coli (E. coli) microorganisms. The osteogenic differentiation was also carried out in order to get gene expressions. The AFM results confirmed that the coatings deposited at 120 W was smoother as compared to other coatings developed at different power, along with optimum contact angle, also these coatings showed good antibacterial results. The fluorescent and viability results of 120 W sample confirmed their good biocompatibility as compared to the coatings deposited 20, 40, 60, and 100 W power. Hence, the coating deposited at 120 W exhibit desirable microstructural characteristics beneficial for surface modification of orthopedic implants.
NASA Astrophysics Data System (ADS)
Nosrati, Rahimeh; Olad, Ali; Nofouzi, Katayoon
2015-08-01
The commercial grade polyacrylic latex was modified in order to prepare a self-cleaning coating. TiO2/Ag-exchanged-zeolite-A nanocomposite was prepared and used as additive in the matrix of polyacrylic latex to achieve a hydrophilic and photocatalytic coating. FTIR and UV-visible spectroscopy, X-ray diffraction patterns and FESEM were used to characterize the composition and structure of the nanocomposites and coatings. The acrylic coatings, were prepared by using of TiO2/Ag-exchanged-zeolite-A additive, had better UV and visible light absorption, hydrophilic, degradation of organic pollutants, stability in water and antimicrobial properties than pristine commercial grade polyacrylic latex coating. According to the results, the modified polyacrylic based coating containing 0.5 wt% of TiO2/Ag-exchanged-zeolite-A nanocomposite additive with TiO2 to Ag-exchanged-zeolite-A ratio of 1:2 was the best coating considering most of useful properties such as small band gap and low water contact angle. The water contact angle for unmodified polyacrylic latex coating was 68° which was decreased to less than 10° in modified coating after 24 h LED lamp illumination.
Novel perovskite coating of strontium zirconate in Inconel substrate
NASA Astrophysics Data System (ADS)
Venkatesh, G.; Blessto, B.; Rao, C. Santhosh Kumar; Subramanian, R.; Berchmans, L. John
2018-02-01
Thermal Barrier Coatings (TBC) provides a low thermal conductivity barrier to heat transfer from the hot gas in the engine to the surface of the coated alloy component. SrZrO3 powder are prepared by Sol Gel synthesis method. The synthesized powder sample is characterized by X Ray Diffraction Technique (XRD), Scanning Electron Microscope (SEM) and Transmission Electron Microscope (TEM) and the results are interpreted. The Polycrystalline nature of SrZrO3 is confirmed and lattice spacing are determined in XRD. SEM shows sub-micron sized particles and a fringed pattern is observed in TEM. The IN718 specimen is Wire Cut and Sand Blasted. A SrZrO3 double layer is coated over the Inconel specimen through a Bond Coat made of NiCoCrAlY by Plasma spraying Process and also characterized. SEM analysis of the Coating shows diffusion of Fe, Sr into the substrate.
Wennemann, L; Hummel, H E
2003-01-01
Field studies in corn (Zea mays L.) were conducted to evaluate distribution patterns of 4-methoxy-cinnamaldehyde (MCA) coated corn grits after aerial application with a Dromader fixed wing aircraft. The kairomone mimic MCA is synthetically available and a quite specific and efficient adult attractant for the invasive alien maize pest western corn rootworm (WCR) Diabrotica virgifera virgifera LeConte. Orientation disruptive properties of MCA for WCR when applied at unphysiologically high concentrations are currently under investigation. For successful implementation of the MCA disruption technique, the distribution patterns of MCA coated corn granules ('grits') in the field are important. Grits are degrained corn cobs, shredded to different sizes, coated with MCA and used as a carrier material to disseminate MCA vapors into corn fields. Granules of 10-12 mesh size were aerially applied eight times at rates ranging from 12.4 to 25.0 kg/ha. The goal is to evaluate distribution patterns of corn grits treated with MCA in three fields located at Csanadpalota, Kardoskút and Mezöhegyes in Southern Hungary between 2000 and 2002. Increasing rates reflect our attempts in finding and optimising the most even distribution of granules in the field. Field experiments were evaluated by collecting grits in 30-cm plastic saucers and by counting grits accumulated on corn plant parts. Variation in grit number per unit area and frequency of corn granule number per plant showed some transient technical application problems. Analysis of grits collected in the saucers revealed some statistical difference between the different application dates as well as differences in rates applied. Altogether grits in saucers were more evenly distributed in comparison to the grits collected on plant parts. As the corn plants age, their leaves and whorls present a smaller and smaller surface area where granules can accumulate. Altogether, however, grit distribution patterns indicate that aerial application is a viable tool for disseminating MCA in corn fields.
Sun, Chi-Chin; Chou, Shih-Feng; Lai, Jui-Yang; Cho, Ching-Hsien; Lee, Chih-Hung
2016-06-01
This study reports, for the first time, the regulation of corneal keratocyte adhesion, spreading, morphology, and integrin gene expression on chitosan coating due to the effects of deacetylation. The degree of deacetylation (DD) in chitosan materials was confirmed by elemental analysis, gel permeation chromatography, and Fourier transform infrared spectroscopy. In this study, chitosan samples with the same molecular weight level but varying DD (74.1 ± 0.5%, 84.4 ± 0.7%, and 94.2 ± 0.5%) were obtained by heat-alkaline treatment under a nitrogen atmosphere. For higher DD groups, the biopolymer carried abundant amino groups since the deacetylation process removed larger amount of acetyl groups from the chitosan molecules. Results showed that the mechanical stability and crystallinity of the chitosan coatings significantly increased with increasing DD value. Fibronectin adsorption, keratocyte adhesion, and cell spreading exhibited a positive correlation with DD due to the chemical functionality of polysaccharides (bearing acetyl and amino groups) and increase of substrate stiffness and crystallinity. In particular, when adhered to chitosan coatings with a DD value of 74.1%, the keratocytes appeared to be fibroblastic, elongated, and spindle shape, indicating a loss of their characteristic dendritic morphology. Furthermore, the gene expression of integrin β1 (i.e., a cell-matrix adhesion molecule) was significantly up-regulated on the chitosan coatings with higher DD, which supports favorable attachment of corneal keratocytes. Our findings suggest that DD-mediated physicochemical properties of chitosan coatings greatly affect cell-substrate crosstalk during corneal keratocyte cultivation. Copyright © 2016 Elsevier B.V. All rights reserved.
Bilayer tablets of Paliperidone for Extended release osmotic drug delivery
NASA Astrophysics Data System (ADS)
Chowdary, K. Sunil; Napoleon, A. A.
2017-11-01
The purpose of this study is to develop and optimize the formulation of paliperidone bilayer tablet core and coating which should meet in vitro performance of trilayered Innovator sample Invega. Optimization of core formulations prepared by different ratio of polyox grades and optimization of coating of (i) sub-coating build-up with hydroxy ethyl cellulose (HEC) and (ii).enteric coating build-up with cellulose acetate (CA). Some important influence factors such as different core tablet compositions and different coating solution ingredients involved in the formulation procedure were investigated. The optimization of formulation and process was conducted by comparing different in vitro release behaviours of Paliperidone. In vitro dissolution studies of Innovator sample (Invega) with formulations of different release rate which ever close release pattern during the whole 24 h test is finalized.
Flower-like Rh/Cu superhydrophobic coating via electrodeposition and its self-cleaning property
NASA Astrophysics Data System (ADS)
Zhao, N.; Lu, S. X.; Xu, W. G.; Cheng, X. L.
2017-01-01
Rh/Cu superhydrophobic coatings with textured flower-like dual micro-nano structures were fabricated on copper substrates via electrodesposition of Rh followed by annealing treatment. The scanning electron microscopy and X-ray diffraction pattern were conducted to analyse the morphology and chemical composition of the coating surfaces, respectively. The water drops exhibited a water contact angle of 168±1° and a sliding angle of 0±1° on the coating surfaces which were obtained by etching in concentrated hydrochloric acid and nitric acid, electrodeposited at -1.0 V for 30 min and annealing in an oven at 180°C for 60 min. The prepared superhydrophobic coatings showed excellent water repellence and self-cleaning property due to its extremely high water contact angle.
2013-08-01
enamel paint. Under extreme plastic deformation, the relative deformation of the coating could cause the coating to separate resulting in loss of...point for one to be found. If a discontinuity, such as a crack , occurs through the object separating speckle pattern, then the strain data will only
Miron, Richard J; Bosshardt, Dieter D; Hedbom, Erik; Zhang, Yufeng; Haenni, Beat; Buser, Daniel; Sculean, Anton
2012-07-01
The use of various combinations of enamel matrix derivative (EMD) and grafting materials has been shown to promote periodontal wound healing/regeneration. However, the downstream cellular behavior of periodontal ligament (PDL) cells and osteoblasts has not yet been studied. Furthermore, it is unknown to what extent the bleeding during regenerative surgery may influence the adsorption of exogenous proteins to the surface of bone grafting materials and the subsequent cellular behavior. In the present study, the aim is to test EMD adsorption to the surface of natural bone mineral (NBM) particles in the presence of blood and determine the effect of EMD coating to NBM particles on downstream cellular pathways, such as adhesion, proliferation, and differentiation of primary human osteoblasts and PDL cells. NBM particles were precoated in various settings with EMD or human blood and analyzed for protein adsorption patterns via fluorescent imaging and high-resolution immunocytochemistry with an anti-EMD antibody. Cell attachment and cell proliferation were quantified using fluorescent double-stranded DNA-binding dye. Cell differentiation was analyzed using real-time polymerase chain reaction for genes encoding runt-related transcription factor 2, alkaline phosphatase (ALP), osteocalcin (OC), and collagen1α1 (COL1A1), and mineralization was assessed using red dye staining. Analysis of cell attachment and cell proliferation revealed significantly higher osteoblast and PDL cell attachment on EMD-coated surfaces when compared with control and blood-coated surfaces. EMD also stimulated release of growth factors and cytokines, including bone morphogenetic protein 2 and transforming growth factor β1. Moreover, there were significantly higher mRNA levels of osteoblast differentiation markers, including COL1A1, ALP, and OC, in osteoblasts and PDL cells cultured on EMD-coated NBM particles. The present results suggest that 1) EMD enhances osteoblast and PDL cell attachment, proliferation, and differentiation on NBM particles, and 2) blood contamination of the grafting material before mixing with EMD may inhibit EMD adsorption.
New approach for pattern collapse problem by increasing contact area at sub-100nm patterning
NASA Astrophysics Data System (ADS)
Lee, Sung-Koo; Jung, Jae Chang; Lee, Min Suk; Lee, Sung K.; Kim, Sam Young; Hwang, Young-Sun; Bok, Cheol K.; Moon, Seung-Chan; Shin, Ki S.; Kim, Sang-Jung
2003-06-01
To accomplish minimizing feature size to sub 100nm, new light sources for photolithography are emerging, such as ArF(193nm), F2(157nm), and EUV(13nm). However as the pattern size decreases to sub 100nm, a new obstacle, that is pattern collapse problem, becomes most serious bottleneck to the road for the sub 100 nm lithography. The main reason for this pattern collapse problem is capillary force that is increased as the pattern size decreases. As a result there were some trials to decrease this capillary force by changing developer or rinse materials that had low surface tension. On the other hands, there were other efforts to increase adhesion between resists and sub materials (organic BARC). In this study, we will propose a novel approach to solve pattern collapse problems by increasing contact area between sub material (organic BARC) and resist pattern. The basic concept of this approach is that if nano-scale topology is made at the sub material, the contact area between sub materials and resist will be increased. The process scheme was like this. First after coating and baking of organic BARC material, the nano-scale topology (3~10nm) was made by etching at this organic BARC material. On this nano-scale topology, resist was coated and exposed. Finally after develop, the contact area between organic BARC and resist could be increased. Though nano-scale topology was made by etching technology, this 20nm topology variation induced large substrate reflectivity of 4.2% and as a result the pattern fidelity was not so good at 100nm 1:1 island pattern. So we needed a new method to improve pattern fidelity problem. This pattern fidelity problem could be solved by introducing a sacrificial BARC layer. The process scheme was like this. First organic BARC was coated of which k value was about 0.64 and then sacrificial BARC layers was coated of which k value was about 0.18 on the organic BARC. The nano-scale topology (1~4nm) was made by etching of this sacrificial BARC layer and then as the same method mentioned above, the contact area between sacrificial layer and resist could be increased. With this introduction of sacrificial layer, the substrate reflectivity of sacrificial BARC layer was decreased enormously to 0.2% though there is 20nm topology variation of sacrificial BARC layer. With this sacrificial BARC layer, we could get 100nm 1:1 L/S pattern. With conventional process, the minimum CD where no collapse occurred, was 96.5nm. By applying this sacrificial BARC layer, the minimum CD where no collapse occurred, was 65.7nm. In conclusion, with nano-scale topology and sacrificial BARC layer, we could get very small pattern that was strong to pattern collapse issue.
Formation of Au nano-patterns on various substrates using simplified nano-transfer printing method
NASA Astrophysics Data System (ADS)
Kim, Jong-Woo; Yang, Ki-Yeon; Hong, Sung-Hoon; Lee, Heon
2008-06-01
For future device applications, fabrication of the metal nano-patterns on various substrates, such as Si wafer, non-planar glass lens and flexible plastic films become important. Among various nano-patterning technologies, nano-transfer print method is one of the simplest techniques to fabricate metal nano-patterns. In nano-transfer printing process, thin Au layer is deposited on flexible PDMS mold, containing surface protrusion patterns, and the Au layer is transferred from PDMS mold to various substrates due to the difference of bonding strength of Au layer to PDMS mold and to the substrate. For effective transfer of Au layer, self-assembled monolayer, which has strong bonding to Au, is deposited on the substrate as a glue layer. In this study, complicated SAM layer coating process was replaced to simple UV/ozone treatment, which can activates the surface and form the -OH radicals. Using simple UV/ozone treatments on both Au and substrate, Au nano-pattern can be successfully transferred to as large as 6 in. diameter Si wafer, without SAM coating process. High fidelity transfer of Au nano-patterns to non-planar glass lens and flexible PET film was also demonstrated.
NASA Astrophysics Data System (ADS)
Song, Xiaoming; Duan, Weike; Huang, Zhinan; Liu, Gaofeng; Wu, Peng; Liu, Tongkun; Li, Ying; Hou, Xilin
2015-09-01
In plants, flowering is the most important transition from vegetative to reproductive growth. The flowering patterns of monocots and eudicots are distinctly different, but few studies have described the evolutionary patterns of the flowering genes in them. In this study, we analysed the evolutionary pattern, duplication and expression level of these genes. The main results were as follows: (i) characterization of flowering genes in monocots and eudicots, including the identification of family-specific, orthologous and collinear genes; (ii) full characterization of CONSTANS-like genes in Brassica rapa (BraCOL genes), the key flowering genes; (iii) exploration of the evolution of COL genes in plant kingdom and construction of the evolutionary pattern of COL genes; (iv) comparative analysis of CO and FT genes between Brassicaceae and Grass, which identified several family-specific amino acids, and revealed that CO and FT protein structures were similar in B. rapa and Arabidopsis but different in rice; and (v) expression analysis of photoperiod pathway-related genes in B. rapa under different photoperiod treatments by RT-qPCR. This analysis will provide resources for understanding the flowering mechanisms and evolutionary pattern of COL genes. In addition, this genome-wide comparative study of COL genes may also provide clues for evolution of other flowering genes.
Clustering change patterns using Fourier transformation with time-course gene expression data.
Kim, Jaehee
2011-01-01
To understand the behavior of genes, it is important to explore how the patterns of gene expression change over a period of time because biologically related gene groups can share the same change patterns. In this study, the problem of finding similar change patterns is induced to clustering with the derivative Fourier coefficients. This work is aimed at discovering gene groups with similar change patterns which share similar biological properties. We developed a statistical model using derivative Fourier coefficients to identify similar change patterns of gene expression. We used a model-based method to cluster the Fourier series estimation of derivatives. We applied our model to cluster change patterns of yeast cell cycle microarray expression data with alpha-factor synchronization. It showed that, as the method clusters with the probability-neighboring data, the model-based clustering with our proposed model yielded biologically interpretable results. We expect that our proposed Fourier analysis with suitably chosen smoothing parameters could serve as a useful tool in classifying genes and interpreting possible biological change patterns.
Binary Gene Expression Patterning of the Molt Cycle: The Case of Chitin Metabolism
Abehsera, Shai; Glazer, Lilah; Tynyakov, Jenny; Plaschkes, Inbar; Chalifa-Caspi, Vered; Khalaila, Isam; Aflalo, Eliahu D.; Sagi, Amir
2015-01-01
In crustaceans, like all arthropods, growth is accompanied by a molting cycle. This cycle comprises major physiological events in which mineralized chitinous structures are built and degraded. These events are in turn governed by genes whose patterns of expression are presumably linked to the molting cycle. To study these genes we performed next generation sequencing and constructed a molt-related transcriptomic library from two exoskeletal-forming tissues of the crayfish Cherax quadricarinatus, namely the gastrolith and the mandible cuticle-forming epithelium. To simplify the study of such a complex process as molting, a novel approach, binary patterning of gene expression, was employed. This approach revealed that key genes involved in the synthesis and breakdown of chitin exhibit a molt-related pattern in the gastrolith-forming epithelium. On the other hand, the same genes in the mandible cuticle-forming epithelium showed a molt-independent pattern of expression. Genes related to the metabolism of glucosamine-6-phosphate, a chitin precursor synthesized from simple sugars, showed a molt-related pattern of expression in both tissues. The binary patterning approach unfolds typical patterns of gene expression during the molt cycle of a crustacean. The use of such a simplifying integrative tool for assessing gene patterning seems appropriate for the study of complex biological processes. PMID:25919476
Wang, Wei; Zhou, Hui; Ma, Baiquan; Owiti, Albert; Korban, Schuyler S; Han, Yuepeng
2016-06-30
Sugars play a variety of roles in plants, and their accumulation in seeds and/or surrounding pericarp tissues is distinctly different between grasses and eudicots. However, little is known about the evolutionary pattern of genes involved in sugar accumulation in these two major groups of flowering plants. Here, we compared evolutionary rates, gene duplication, and selective patterns of genes involved in sugar metabolism and transport between grasses and eudicots using six grass species and seven eudicot species as materials. Overall, sugar transporter genes exhibit divergent evolutionary patterns, whereas, sugar metabolism genes showing similar evolutionary pattern between monocots and eudicots. Sugar transporter genes have higher frequencies of recent duplication in eudicots than in grasses and their patterns of evolutionary rate are different. Evidence for divergent selection of these two groups of flowering plants is also observed in sugar transporter genes, wherein, these genes have undergone positive selection in eudicots, but not in grasses. Taken together, these findings suggest that sugar transporter genes rather than sugar metabolism genes play important roles in sugar accumulation in plants, and that divergent evolutionary patterns of sugar transporter genes are associated with the difference of sugar accumulation in storage tissues of grasses and eudicots.
Wang, Wei; Zhou, Hui; Ma, Baiquan; Owiti, Albert; Korban, Schuyler S.; Han, Yuepeng
2016-01-01
Sugars play a variety of roles in plants, and their accumulation in seeds and/or surrounding pericarp tissues is distinctly different between grasses and eudicots. However, little is known about the evolutionary pattern of genes involved in sugar accumulation in these two major groups of flowering plants. Here, we compared evolutionary rates, gene duplication, and selective patterns of genes involved in sugar metabolism and transport between grasses and eudicots using six grass species and seven eudicot species as materials. Overall, sugar transporter genes exhibit divergent evolutionary patterns, whereas, sugar metabolism genes showing similar evolutionary pattern between monocots and eudicots. Sugar transporter genes have higher frequencies of recent duplication in eudicots than in grasses and their patterns of evolutionary rate are different. Evidence for divergent selection of these two groups of flowering plants is also observed in sugar transporter genes, wherein, these genes have undergone positive selection in eudicots, but not in grasses. Taken together, these findings suggest that sugar transporter genes rather than sugar metabolism genes play important roles in sugar accumulation in plants, and that divergent evolutionary patterns of sugar transporter genes are associated with the difference of sugar accumulation in storage tissues of grasses and eudicots. PMID:27356489
Park, Jaewon; Kim, Hyun Soo; Han, Arum
2009-01-01
A poly(dimethylsiloxane) (PDMS) patterning method based on a photoresist lift-off technique to make an electrical insulation layer with selective openings is presented. The method enables creating PDMS patterns with small features and various thicknesses without any limitation in the designs and without the need for complicated processes or expensive equipments. Patterned PDMS layers were created by spin-coating liquid phase PDMS on top of a substrate having sacrificial photoresist patterns, followed by a photoresist lift-off process. The thickness of the patterned PDMS layers could be accurately controlled (6.5–24 µm) by adjusting processing parameters such as PDMS spin-coating speeds, PDMS dilution ratios, and sacrificial photoresist thicknesses. PDMS features as small as 15 µm were successfully patterned and the effects of each processing parameter on the final patterns were investigated. Electrical resistance tests between adjacent electrodes with and without the insulation layer showed that the patterned PDMS layer functions properly as an electrical insulation layer. Biocompatibility of the patterned PDMS layer was confirmed by culturing primary neuron cells on top of the layer for up to two weeks. An extensive neuronal network was successfully formed, showing that this PDMS patterning method can be applied to various biosensing microdevices. The utility of this fabrication method was further demonstrated by successfully creating a patterned electrical insulation layer on flexible substrates containing multi-electrode arrays. PMID:19946385
Nganga, Sara; Moritz, Niko; Kolakovic, Ruzica; Jakobsson, Kristina; Nyman, Johan O; Borgogna, Massimiliano; Travan, Andrea; Crosera, Matteo; Donati, Ivan; Vallittu, Pekka K; Sandler, Niklas
2014-10-22
Biostable fiber-reinforced composites, based on bisphenol-A-dimethacrylate and triethyleneglycoldimethacrylate thermoset polymer matrix reinforced with E-glass fibers have been successfully used in cranial reconstructions and the material has been approved for clinical use. As a further refinement of these implants, antimicrobial, non-cytotoxic coatings on the composites were created by an immersion procedure driven by strong electrostatic interactions. Silver nanoparticles (nAg) were immobilized in lactose-modified chitosan (Chitlac) to prepare the bacteriostatic coatings. Herein, we report the use of inkjet technology (a drop-on-demand inkjet printer) to deposit functional Chitlac-nAg coatings on the thermoset substrates. Characterization methods included scanning electron microscopy, scanning white light interferometry and electro-thermal atomic absorption spectroscopy. Inkjet printing enabled the fast and flexible functionalization of the thermoset surfaces with controlled coating patterns. The coatings were not impaired by the printing process: the kinetics of silver release from the coatings created by inkjet printing and conventional immersion technique was similar. Further research is foreseen to optimize printing parameters and to tailor the characteristics of the coatings for specific clinical applications.
Mathematical modeling of the in-mold coating process for injection-molded thermoplastic parts
NASA Astrophysics Data System (ADS)
Chen, Xu
In-Mold Coating (IMC) has been successfully used for many years for exterior body panels made from compression molded Sheet Molding Compound (SMC). The coating material is a single component reactive fluid, designed to improve the surface quality of SMC moldings in terms of functional and cosmetic properties. When injected onto a cured SMC part, IMC cures and bonds to provide a pain-like surface. Because of its distinct advantages, IMC is being considered for application to injection molded thermoplastic parts. For a successful in mold coating operation, there are two key issues related to the flow of the coating. First, the injection nozzle should be located such that the thermoplastic substrate is totally covered and the potential for air trapping is minimized. The selected location should be cosmetically acceptable since it most likely will leave a mark on the coated surface. The nozzle location also needs to be accessible for easy of maintenance. Secondly, the hydraulic force generated by the coating injection pressure should not exceed the available clamping tonnage. If the clamping force is exceeded, coating leakage will occur. In this study, mathematical models for IMC flow on the compressible thermoplastic substrate have been developed. Finite Difference Method (FDM) is first used to solve the 1 dimensional (1D) IMC flow problem. In order to investigate the application of Control Volume based Finite Element Method (CV/FEM) to more complicated two dimensional IMC flow, that method is first evaluated by solving the 1D IMC flow problem. An analytical solution, which can be obtained when a linear relationship between the coating thickness and coating injection pressure is assumed, is used to verify the numerical results. The mathematical models for the 2 dimensional (2D) IMC flow are based on the generalized Hele-Shaw approximation. It has been found experimentally that the power law viscosity model adequately predicts the rheological behavior of the coating. The compressibility of the substrate is modeled by the 2-domain Tait PVT equation. CV/FEM is used to solve the discretized governing equations. A computer code has been developed to predict the fill pattern of the coating and the injection pressure. A number of experiments have been conducted to verify the numerical predictions of the computer code. It has been found both numerically and experimentally that the substrate thickness plays a significant role on the IMC fill pattern.
NASA Astrophysics Data System (ADS)
Li, Guo; Su, Hang; Kuhn, Uwe; Meusel, Hannah; Ammann, Markus; Shao, Min; Pöschl, Ulrich; Cheng, Yafang
2018-02-01
Coated-wall flow tube reactors are frequently used to investigate gas uptake and heterogeneous or multiphase reaction kinetics under laminar flow conditions. Coating surface roughness may potentially distort the laminar flow pattern, induce turbulence and introduce uncertainties in the calculated uptake coefficient based on molecular diffusion assumptions (e.g., Brown/Cooney-Kim-Davis (CKD)/Knopf-Pöschl-Shiraiwa (KPS) methods), which has not been fully resolved in earlier studies. Here, we investigate the influence of surface roughness and local turbulence on coated-wall flow tube experiments for gas uptake and kinetic studies. According to laminar boundary theory and considering the specific flow conditions in a coated-wall flow tube, we derive and propose a critical height δc to evaluate turbulence effects in the design and analysis of coated-wall flow tube experiments. If a geometric coating thickness δg is larger than δc, the roughness elements of the coating may cause local turbulence and result in overestimation of the real uptake coefficient (γ). We further develop modified CKD/KPS methods (i.e., CKD-LT/KPS-LT) to account for roughness-induced local turbulence effects. By combination of the original methods and their modified versions, the maximum error range of γCKD (derived with the CKD method) or γKPS (derived with the KPS method) can be quantified and finally γ can be constrained. When turbulence is generated, γCKD or γKPS can bear large difference compared to γ. Their difference becomes smaller for gas reactants with lower uptake (i.e., smaller γ) and/or for a smaller ratio of the geometric coating thickness to the flow tube radius (δg / R0). On the other hand, the critical height δc can also be adjusted by optimizing flow tube configurations and operating conditions (i.e., tube diameter, length, and flow velocity), to ensure not only unaffected laminar flow patterns but also other specific requirements for an individual flow tube experiment. We use coating thickness values from previous coated-wall flow tube studies to assess potential roughness effects using the δc criterion. In most studies, the coating thickness was sufficiently small to avoid complications, but some may have been influenced by surface roughness and local turbulence effects.
Adefenwa, Mufliat A; Peters, Sunday O; Agaviezor, Brilliant O; Wheto, Matthew; Adekoya, Khalid O; Okpeku, Moses; Oboh, Bola; Williams, Gabriel O; Adebambo, Olufunmilayo A; Singh, Mahipal; Thomas, Bolaji; De Donato, Marcos; Imumorin, Ikhide G
2013-07-01
The agouti-signaling protein (ASIP) plays a major role in mammalian pigmentation as an antagonist to melanocortin-1 receptor gene to stimulate pheomelanin synthesis, a major pigment conferring mammalian coat color. We sequenced a 352 bp fragment of ASIP gene spanning part of exon 2 and part of intron 2 in 215 animals representing six goat breeds from Nigeria and the United States: West African Dwarf, predominantly black; Red Sokoto, mostly red; and Sahel, mostly white from Nigeria; black and white Alpine, brown and white Spanish and white Saanen from the US. Twenty haplotypes from nine mutations representing three intronic, one silent and five missense (p.S19R, p.N35K, p.L36V, p.M42L and p.L45W) mutations were identified in Nigerian goats. Approximately 89 % of Nigerian goats carry haplotype 1 (TGCCATCCG) which seems to be the wild type configuration of mutations in this region of the gene. Although we found no association between these polymorphisms in the ASIP gene and coat color in Nigerian goats, in-silico functional analysis predicts putative deleterious functional impact of the p.L45W mutation on the basic amino-terminal domain of ASIP. In the American goats, two intronic mutations, g.293G>A and g.327C>A, were identified in the Alpine breed, although the g.293G>A mutation is common to American and Nigerian goat populations. All Sannen and Sahel goats in this study belong to haplotypes 1 of both populations which seem to be the wild-type composite ASIP haplotype. Overall, there was no clear association of this portion of the ASIP gene interrogated in this study with coat color variation. Therefore, additional genomic analyses of promoter sequence, the entire coding and non-coding regions of the ASIP gene will be required to obtain a definite conclusion.
Localized transfection on arrays of magnetic beads coated with PCR products.
Isalan, Mark; Santori, Maria Isabel; Gonzalez, Cayetano; Serrano, Luis
2005-02-01
High-throughput gene analysis would benefit from new approaches for delivering DNA or RNA into cells. Here we describe a simple system that allows any molecular biology laboratory to carry out multiple, parallel cell transfections on microscope coverslip arrays. By using magnetically defined positions and PCR product-coated paramagnetic beads, we achieved transfection in a variety of cell lines. Beads may be added to the cells at any time, allowing both spatial and temporal control of transfection. Because the beads may be coated with more than one gene construct, the method can be used to achieve cotransfection within single cells. Furthermore, PCR-generated mutants may be conveniently screened, bypassing cloning and plasmid purification steps. We illustrated the applicability of the method by screening combinatorial peptide libraries, fused to GFP, to identify previously unknown cellular localization motifs. In this way, we identified several localizing peptides, including structured localization signals based around the scaffold of a single C2H2 zinc finger.
The pomegranate (Punica granatum L.) genome and the genomics of punicalagin biosynthesis.
Qin, Gaihua; Xu, Chunyan; Ming, Ray; Tang, Haibao; Guyot, Romain; Kramer, Elena M; Hu, Yudong; Yi, Xingkai; Qi, Yongjie; Xu, Xiangyang; Gao, Zhenghui; Pan, Haifa; Jian, Jianbo; Tian, Yinping; Yue, Zhen; Xu, Yiliu
2017-09-01
Pomegranate (Punica granatum L.) is a perennial fruit crop grown since ancient times that has been planted worldwide and is known for its functional metabolites, particularly punicalagins. We have sequenced and assembled the pomegranate genome with 328 Mb anchored into nine pseudo-chromosomes and annotated 29 229 gene models. A Myrtales lineage-specific whole-genome duplication event was detected that occurred in the common ancestor before the divergence of pomegranate and Eucalyptus. Repetitive sequences accounted for 46.1% of the assembled genome. We found that the integument development gene INNER NO OUTER (INO) was under positive selection and potentially contributed to the development of the fleshy outer layer of the seed coat, an edible part of pomegranate fruit. The genes encoding the enzymes for synthesis and degradation of lignin, hemicelluloses and cellulose were also differentially expressed between soft- and hard-seeded varieties, reflecting differences in their accumulation in cultivars differing in seed hardness. Candidate genes for punicalagin biosynthesis were identified and their expression patterns indicated that gallic acid synthesis in tissues could follow different biochemical pathways. The genome sequence of pomegranate provides a valuable resource for the dissection of many biological and biochemical traits and also provides important insights for the acceleration of breeding. Elucidation of the biochemical pathway(s) involved in punicalagin biosynthesis could assist breeding efforts to increase production of this bioactive compound. © 2017 The Authors The Plant Journal © 2017 John Wiley & Sons Ltd.
Pattern-Forming Instabilities: A Phenomenological Approach through Simple Examples
ERIC Educational Resources Information Center
Brunet, Philippe
2007-01-01
From the streets of clouds to the submarine sand ripples or the striations on the coats of some animals, nature offers many examples of spontaneous patterned structures originating from various instabilities. These patterns can in turn destabilize and show a rich, complex dynamics and possibly end up in disordered behaviours. For over 20 years,…
Boulila, Moncef
2010-06-01
To enhance the knowledge of recombination as an evolutionary process, 267 accessions retrieved from GenBank were investigated, all belonging to five economically important viruses infecting fruit crops (Plum pox, Apple chlorotic leaf spot, Apple mosaic, Prune dwarf, and Prunus necrotic ringspot viruses). Putative recombinational events were detected in the coat protein (CP)-encoding gene using RECCO and RDP version 3.31beta algorithms. Based on RECCO results, all five viruses were shown to contain potential recombination signals in the CP gene. Reconstructed trees with modified topologies were proposed. Furthermore, RECCO performed better than the RDP package in detecting recombination events and exhibiting their evolution rate along the sequences of the five viruses. RDP, however, provided the possible major and minor parents of the recombinants. Thus, the two methods should be considered complementary.
Synthesis and characterization of nanomagnetite particles and their polymer coated forms.
Utkan, Guldem Guven; Sayar, Filiz; Batat, Pinar; Ide, Semra; Kriechbaum, Manfred; Pişkin, Erhan
2011-01-15
Superparamagnetic nanoparticles were prepared by coprecipitation of ferrous (Fe(2+)) and ferric (Fe(3+)) aqueous solution by a base. Nanomagnetite particles were coated with poly(St/PEG-EEM/DMAPM) and poly(St/PEG-MA/DMAPM) layer by emulsifier-free emulsion polymerization. Chemical structure of nanoparticles was characterized by both FTIR and (1)H NMR. Particle morphologies were determined by Zeta Sizer, DLS, XRD and SAXS. Structural analysis showed that after polymer coating nanomagnetite particles kept their superparamagnetic property. Besides the synthesized magnetites, polymer coated forms of these particles are more biocompatible, well dispersable and uniform. These properties make them a very strong candidate for bioengineering applications, such as bioseparation, gene transfer. Copyright © 2010 Elsevier Inc. All rights reserved.
Low thermal distortion Extreme-UV lithography reticle and method
Gianoulakis, Steven E.; Ray-Chaudhuri, Avijit K.
2002-01-01
Thermal distortion of reticles or masks can be significantly reduced by emissivity engineering, i.e., the selective placement or omission of coatings on the reticle. Reflective reticles so fabricated exhibit enhanced heat transfer thereby reducing the level of thermal distortion and ultimately improving the quality of the transcription of the reticle pattern onto the wafer. Reflective reticles include a substrate having an active region that defines the mask pattern and non-active region(s) that are characterized by a surface that has a higher emissivity than that of the active region. The non-active regions are not coated with the radiation reflective material.
NASA Astrophysics Data System (ADS)
Herbert, D. P.; Al-Hassani, A. H. M.; Richardson, M. O. W.
The ESPI (electronic speckle pattern interferometry) technique at high magnification levels is demonstrated to be of considerable value in interpreting the fracture behaviour of epoxy resins. The fracture toughness of powder coating system at different thicknesses has been measured using a TDCB (tapered double cantilever beam) technique and the deformation zone at the tip of the moving crack monitored. Initial indications are that a mechanistic changeover occurs at a critical bond (coating) thickness and that this is synonymous with the occurence of a fracture toughness maximum, which in turn is associated with a deformation zone of specific diameter.
Zhou, Jianhong; Zhao, Lingzhou; Li, Bo; Han, Yong
2018-04-14
Hierarchical micropore/nanorod-patterned strontium doped hydroxyapatite (Ca 9 Sr 1 (PO 4 ) 6 (OH) 2 , Sr 1 -HA) structures (MNRs) with different nanorod diameters of about 30, 70 and 150 nm were coated on titanium, to investigate the effect of nanorod diameter on osteogenesis and the involved mechanism. Compared to micropore/nanogranule-patterned Sr 1 -HA coating (MNG), MNRs gave rise to dramatically enhanced in vitro mesenchymal stem cell functions including osteogenic differentiation in the absence of osteogenic supplements and in vivo osseointegration related to the nanorod diameter with about 70 nm displaying the best effects. MNRs activated the cellular Wnt/β-catenin pathway by increasing the expression of Wnt3a and LRP6 and decreasing the expression of Wnt/β-catenin pathway antagonists (sFRP1, sFRP2, Dkk1 and Dkk2). The exogenous Wnt3a significantly enhanced the β-catenin signaling activation and cell differentiation on MNG, and the exogenous Dkk1 attenuated the enhancing effect of MNRs on them. The data demonstrate that MNRs favor osseointegration via a Wnt/β-catenin pathway. Copyright © 2018 Elsevier Inc. All rights reserved.
Laser Processing of Multilayered Thermal Spray Coatings: Optimal Processing Parameters
NASA Astrophysics Data System (ADS)
Tewolde, Mahder; Zhang, Tao; Lee, Hwasoo; Sampath, Sanjay; Hwang, David; Longtin, Jon
2017-12-01
Laser processing offers an innovative approach for the fabrication and transformation of a wide range of materials. As a rapid, non-contact, and precision material removal technology, lasers are natural tools to process thermal spray coatings. Recently, a thermoelectric generator (TEG) was fabricated using thermal spray and laser processing. The TEG device represents a multilayer, multimaterial functional thermal spray structure, with laser processing serving an essential role in its fabrication. Several unique challenges are presented when processing such multilayer coatings, and the focus of this work is on the selection of laser processing parameters for optimal feature quality and device performance. A parametric study is carried out using three short-pulse lasers, where laser power, repetition rate and processing speed are varied to determine the laser parameters that result in high-quality features. The resulting laser patterns are characterized using optical and scanning electron microscopy, energy-dispersive x-ray spectroscopy, and electrical isolation tests between patterned regions. The underlying laser interaction and material removal mechanisms that affect the feature quality are discussed. Feature quality was found to improve both by using a multiscanning approach and an optional assist gas of air or nitrogen. Electrically isolated regions were also patterned in a cylindrical test specimen.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Corbin, Cyrielle; Drouet, Samantha; Markulin, Lucija
Identification of DIR encoding genes in flax genome. Analysis of phylogeny, gene/protein structures and evolution. Identification of new conserved motifs linked to biochemical functions. Investigation of spatio-temporal gene expression and response to stress. Dirigent proteins (DIRs) were discovered during 8-8' lignan biosynthesis studies, through identification of stereoselective coupling to afford either (+)- or (-)-pinoresinols from E-coniferyl alcohol. DIRs are also involved or potentially involved in terpenoid, allyl/propenyl phenol lignan, pterocarpan and lignin biosynthesis. DIRs have very large multigene families in different vascular plants including flax, with most still of unknown function. DIR studies typically focus on a small subset ofmore » genes and identification of biochemical/physiological functions. Herein, a genome-wide analysis and characterization of the predicted flax DIR 44-membered multigene family was performed, this species being a rich natural grain source of 8-8' linked secoisolariciresinol-derived lignan oligomers. All predicted DIR sequences, including their promoters, were analyzed together with their public gene expression datasets. Expression patterns of selected DIRs were examined using qPCR, as well as through clustering analysis of DIR gene expression. These analyses further implicated roles for specific DIRs in (-)-pinoresinol formation in seed-coats, as well as (+)-pinoresinol in vegetative organs and/or specific responses to stress. Phylogeny and gene expression analysis segregated flax DIRs into six distinct clusters with new cluster-specific motifs identified. We propose that these findings can serve as a foundation to further systematically determine functions of DIRs, i.e. other than those already known in lignan biosynthesis in flax and other species. Given the differential expression profiles and inducibility of the flax DIR family, we provisionally propose that some DIR genes of unknown function could be involved in different aspects of secondary cell wall biosynthesis and plant defense.« less
Corbin, Cyrielle; Drouet, Samantha; Markulin, Lucija; Auguin, Daniel; Lainé, Éric; Davin, Laurence B; Cort, John R; Lewis, Norman G; Hano, Christophe
2018-05-01
Identification of DIR encoding genes in flax genome. Analysis of phylogeny, gene/protein structures and evolution. Identification of new conserved motifs linked to biochemical functions. Investigation of spatio-temporal gene expression and response to stress. Dirigent proteins (DIRs) were discovered during 8-8' lignan biosynthesis studies, through identification of stereoselective coupling to afford either (+)- or (-)-pinoresinols from E-coniferyl alcohol. DIRs are also involved or potentially involved in terpenoid, allyl/propenyl phenol lignan, pterocarpan and lignin biosynthesis. DIRs have very large multigene families in different vascular plants including flax, with most still of unknown function. DIR studies typically focus on a small subset of genes and identification of biochemical/physiological functions. Herein, a genome-wide analysis and characterization of the predicted flax DIR 44-membered multigene family was performed, this species being a rich natural grain source of 8-8' linked secoisolariciresinol-derived lignan oligomers. All predicted DIR sequences, including their promoters, were analyzed together with their public gene expression datasets. Expression patterns of selected DIRs were examined using qPCR, as well as through clustering analysis of DIR gene expression. These analyses further implicated roles for specific DIRs in (-)-pinoresinol formation in seed-coats, as well as (+)-pinoresinol in vegetative organs and/or specific responses to stress. Phylogeny and gene expression analysis segregated flax DIRs into six distinct clusters with new cluster-specific motifs identified. We propose that these findings can serve as a foundation to further systematically determine functions of DIRs, i.e. other than those already known in lignan biosynthesis in flax and other species. Given the differential expression profiles and inducibility of the flax DIR family, we provisionally propose that some DIR genes of unknown function could be involved in different aspects of secondary cell wall biosynthesis and plant defense.
Function does not follow form in gene regulatory circuits.
Payne, Joshua L; Wagner, Andreas
2015-08-20
Gene regulatory circuits are to the cell what arithmetic logic units are to the chip: fundamental components of information processing that map an input onto an output. Gene regulatory circuits come in many different forms, distinct structural configurations that determine who regulates whom. Studies that have focused on the gene expression patterns (functions) of circuits with a given structure (form) have examined just a few structures or gene expression patterns. Here, we use a computational model to exhaustively characterize the gene expression patterns of nearly 17 million three-gene circuits in order to systematically explore the relationship between circuit form and function. Three main conclusions emerge. First, function does not follow form. A circuit of any one structure can have between twelve and nearly thirty thousand distinct gene expression patterns. Second, and conversely, form does not follow function. Most gene expression patterns can be realized by more than one circuit structure. And third, multifunctionality severely constrains circuit form. The number of circuit structures able to drive multiple gene expression patterns decreases rapidly with the number of these patterns. These results indicate that it is generally not possible to infer circuit function from circuit form, or vice versa.
Characterization of reference gene expression in tung tree (Vernicia fordii)
USDA-ARS?s Scientific Manuscript database
Tung oil from tung tree (Vernicia fordii) is widely used as a drying ingredient in paints, varnishes, and other coatings and finishes. Recent research has focused on the understanding of the biosynthesis of oil in tung trees. Many oil biosynthetic genes have been identified in tung tree but little...
Identification and characterization of microRNAs in white and brown alpaca skin
2012-01-01
Background MicroRNAs (miRNAs) are small, non-coding 21–25 nt RNA molecules that play an important role in regulating gene expression. Little is known about the expression profiles and functions of miRNAs in skin and their role in pigmentation. Alpacas have more than 22 natural coat colors, more than any other fiber producing species. To better understand the role of miRNAs in control of coat color we performed a comprehensive analysis of miRNA expression profiles in skin of white versus brown alpacas. Results Two small RNA libraries from white alpaca (WA) and brown alpaca (BA) skin were sequenced with the aid of Illumina sequencing technology. 272 and 267 conserved miRNAs were obtained from the WA and BA skin libraries, respectively. Of these conserved miRNAs, 35 and 13 were more abundant in WA and BA skin, respectively. The targets of these miRNAs were predicted and grouped based on Gene Ontology and KEGG pathway analysis. Many predicted target genes for these miRNAs are involved in the melanogenesis pathway controlling pigmentation. In addition to the conserved miRNAs, we also obtained 22 potentially novel miRNAs from the WA and BA skin libraries. Conclusion This study represents the first comprehensive survey of miRNAs expressed in skin of animals of different coat colors by deep sequencing analysis. We discovered a collection of miRNAs that are differentially expressed in WA and BA skin. The results suggest important potential functions of miRNAs in coat color regulation. PMID:23067000
DOE Office of Scientific and Technical Information (OSTI.GOV)
Parent, Kristin N., E-mail: kparent@msu.edu; Tang, Jinghua; Cardone, Giovanni
CUS-3 is a short-tailed, dsDNA bacteriophage that infects serotype K1 Escherichia coli. We report icosahedrally averaged and asymmetric, three-dimensional, cryo-electron microscopic reconstructions of the CUS-3 virion. Its coat protein structure adopts the “HK97-fold” shared by other tailed phages and is quite similar to that in phages P22 and Sf6 despite only weak amino acid sequence similarity. In addition, these coat proteins share a unique extra external domain (“I-domain”), suggesting that the group of P22-like phages has evolved over a very long time period without acquiring a new coat protein gene from another phage group. On the other hand, the morphologymore » of the CUS-3 tailspike differs significantly from that of P22 or Sf6, but is similar to the tailspike of phage K1F, a member of the extremely distantly related T7 group of phages. We conclude that CUS-3 obtained its tailspike gene from a distantly related phage quite recently. - Highlights: • Asymmetric and symmetric three-dimensional reconstructions of phage CUS-3 are presented. • CUS-3 major capsid protein has a conserved I-domain, which is found in all three categories of “P22-like phage”. • CUS-3 has very different tailspike receptor binding domain from those of P22 and Sf6. • The CUS-3 tailspike likely was acquired by horizontal gene transfer.« less
Coaxial twin-fluid atomization with pattern air gas streams
NASA Astrophysics Data System (ADS)
Hei Ng, Chin; Aliseda, Alberto
2010-11-01
Coaxial twin-fluid atomization has numerous industrial applications, most notably fuel injection and spray coating. In the coating process of pharmaceutical tablets, the coaxial atomizing air stream is accompanied by two diametrically opposed side jets that impinge on the liquid/gas coaxial jets at an angle to produce an elliptical shape of the spray's cross section. Our study focuses on the influence of these side jets on the break up process and on the droplet velocity and diameter distribution along the cross section. The ultimate goal is to predict the size distribution and volume flux per unit area in the spray. With this predictive model, an optimal atomizing air/pattern air ratio can be found to achieve the desired coating result. This model is also crucial in scaling up the laboratory setup to production level. We have performed experiments with different atomized liquids, such as water and glycerine-water mixtures, that allow us to establish the effect of liquid viscosity, through the Ohnesorge number, in the spray characteristics. The gas Reynolds number of our experiments ranges from 9000 to 18000 and the Weber number ranges from 400 to 1600. We will present the effect of pattern air in terms of the resulting droplets size, droplet number density and velocity at various distances downstream of the nozzle where the effect of pattern air is significant.
Sato, Toshinori; Nakata, Mitsuhiro; Yang, Zhihong; Torizuka, Yu; Kishimoto, Satoko; Ishihara, Masayuki
2017-08-01
Lyophilization is an effective method for preserving nonviral gene vectors. To improve the stability and transgene expression of lyophilized plasmid DNA (pDNA) complexes, we coated the surfaces of pDNA/chitosan complexes with hyaluronic acid (HA) of varying molecular masses. The transgene expression of pDNA/chitosan/HA ternary complexes was characterized in vitro and in vivo. pDNA complexes were lyophilized overnight and the resultant products with spongy, porous consistencies were stored at -30, 4 or 25°C for 2 weeks. Rehydrated complexes were characterized using gel retardation assays, aiming to confirm complex formation, measure particle size and evaluate zeta potential, as well as conduct luciferase gene reporter assays. The anti-tumor effects of pDNA ternary complexes were evaluated using suicide gene (pTK) coding thymidine kinase in Huh7-implanted mice. Transfection efficiencies of pDNA/chitosan/HA ternary complexes were dependent on the average molecular masses of HA. The coating of pDNA/chitosan complexes with HA maintained the cellular transfection efficiencies of lyophilized pDNA ternary complexes. Furthermore, intratumoral injection of lyophilized, rehydrated pDNA ternary complexes into tumor-bearing mice showed a significant suppression of tumor growth. The coating of pDNA/chitosan complexes with high-molecular-weight HA augmented the stability and cellular transfection ability of the complexes after lyophilization-rehydration. Copyright © 2017 John Wiley & Sons, Ltd.
Arsovski, Andrej A.; Villota, Maria M.; Rowland, Owen; Subramaniam, Rajagopal; Western, Tamara L.
2009-01-01
Pollination triggers not only embryo development but also the differentiation of the ovule integuments to form a specialized seed coat. The mucilage secretory cells of the Arabidopsis thaliana seed coat undergo a complex differentiation process in which cell growth is followed by the synthesis and secretion of pectinaceous mucilage. A number of genes have been identified affecting mucilage secretory cell differentiation, including MUCILAGE-MODIFIED4 (MUM4). mum4 mutants produce a reduced amount of mucilage and cloning of MUM4 revealed that it encodes a UDP-L-rhamnose synthase that is developmentally up-regulated to provide rhamnose for mucilage pectin synthesis. To identify additional genes acting in mucilage synthesis and secretion, a screen for enhancers of the mum4 phenotype was performed. Eight mum enhancers (men) have been identified, two of which result from defects in known mucilage secretory cell genes (MUM2 and MYB61). Our results show that, in a mum4 background, mutations in MEN1, MEN4, and MEN5 lead to further reductions in mucilage compared to mum4 single mutants, suggesting that they are involved in mucilage synthesis or secretion. Conversely, mutations in MEN2 and MEN6 appear to affect mucilage release rather than quantity. With the exception of men4, whose single mutant exhibits reduced mucilage, none of these genes have a single mutant phenotype, suggesting that they would not have been identified outside the compromised mum4 background. PMID:19401413
Zanek, María Cecilia; Reyes, Carina Andrea; Cervera, Magdalena; Peña, Eduardo José; Velázquez, Karelia; Costa, Norma; Plata, Maria Inés; Grau, Oscar; Peña, Leandro; García, María Laura
2008-01-01
Citrus psorosis is a serious viral disease affecting citrus trees in many countries. Its causal agent is Citrus psorosis virus (CPsV), the type member of genus Ophiovirus. CPsV infects most important citrus varieties, including oranges, mandarins and grapefruits, as well as hybrids and citrus relatives used as rootstocks. Certification programs have not been sufficient to control the disease and no sources of natural resistance have been found. Pathogen-derived resistance (PDR) can provide an efficient alternative to control viral diseases in their hosts. For this purpose, we have produced 21 independent lines of sweet orange expressing the coat protein gene of CPsV and five of them were challenged with the homologous CPV 4 isolate. Two different viral loads were evaluated to challenge the transgenic plants, but so far, no resistance or tolerance has been found in any line after 1 year of observations. In contrast, after inoculation all lines showed characteristic symptoms of psorosis in the greenhouse. The transgenic lines expressed low and variable amounts of the cp gene and no correlation was found between copy number and transgene expression. One line contained three copies of the cp gene, expressed low amounts of the mRNA and no coat protein. The ORF was cytosine methylated suggesting a PTGS mechanism, although the transformant failed to protect against the viral load used. Possible causes for the failed protection against the CPsV are discussed.
Microstructure and Mechanical Properties of Zn-Ni-Al2O3 Composite Coatings
Bai, Yang; Wang, Zhenhua; Li, Xiangbo; Huang, Guosheng; Li, Caixia
2018-01-01
Zn-Ni-Al2O3 composite coatings with different Ni contents were fabricated by low-pressure cold spray (LPCS) technology. The effects of the Ni content on the microstructural and mechanical properties of the coatings were investigated. According to X-ray diffraction patterns, the composite coatings were primarily composed of metallic-phase Zn and Ni and ceramic-phase Al2O3. The energy-dispersive spectroscopy results show that the Al2O3 content of the composite coatings gradually decreased with increasing of Ni content. The cross-sectional morphology revealed thick, dense coatings with a wave-like stacking structure. The process of depositing Zn and Ni particles and Al2O3 particles by the LPCS method was examined, and the deposition mechanism was demonstrated to be mechanical interlocking. The bond strength, micro hardness and friction coefficient of the coatings did not obviously change when the Ni content varied. The presence of Al2O3 and Ni increased the wear resistance of the composite coatings, which was higher than that of pure Zn coatings, and the wear mechanism was abrasive and adhesive wear. PMID:29883391
Design and In Vitro Evaluation of Compression-coated Pulsatile Release Tablets of Losartan Potassium
Bajpai, M.; Singh, D. C. P.; Bhattacharya, A.; Singh, A.
2012-01-01
In majority of individuals blood pressure rises in the early morning hours, which lead to serious cardiovascular complications. Formulation of pulsatile system makes it possible to deliver drug at definite period of time when symptoms of the disease condition are most critical. The purpose of the present work was to develop pulsatile release tablet of losartan potassium for chronotherapy in hypertension. The prepared system consisted of a core tablet coated with versatile and safe hydrophilic cellulosic ethers such as, hydroxypropyl methylcellulose, hydroxypropyl cellulose and sodium carboxy methylcellulose to produce burst release after predetermined lag time. Various formulation factors were studied through series of test and in vitro dissolution study. It was found that core tablets containing superdisintegrant failed to produce burst drug release pattern while effervescent agent was able to do so. Results also reveal that coating composition and coating level affects lag time. Formulation containing effervescent agent in core and coated with 200 mg hydroxypropyl cellulose provide lag time of 4.5 h with 73% drug release in 6 h that followed a sigmoidal release pattern. These values were close to the desired objective of producing lag time of 5-6 h followed by fast drug release. This approach can thus provide a useful means for timed release of losartan and is helpful for patients with morning surge. PMID:23325989
MYB107 and MYB9 Homologs Regulate Suberin Deposition in Angiosperms
Cohen, Hagai; Levy-Samocha, Dorit; Tzfadia, Oren; Panizel, Irina; Zeisler, Viktoria; Massalha, Hassan; Stern, Adi; Aharoni, Asaph
2016-01-01
Suberin, a polymer composed of both aliphatic and aromatic domains, is deposited as a rough matrix upon plant surface damage and during normal growth in the root endodermis, bark, specialized organs (e.g., potato [Solanum tuberosum] tubers), and seed coats. To identify genes associated with the developmental control of suberin deposition, we investigated the chemical composition and transcriptomes of suberized tomato (Solanum lycopersicum) and russet apple (Malus x domestica) fruit surfaces. Consequently, a gene expression signature for suberin polymer assembly was revealed that is highly conserved in angiosperms. Seed permeability assays of knockout mutants corresponding to signature genes revealed regulatory proteins (i.e., AtMYB9 and AtMYB107) required for suberin assembly in the Arabidopsis thaliana seed coat. Seeds of myb107 and myb9 Arabidopsis mutants displayed a significant reduction in suberin monomers and altered levels of other seed coat-associated metabolites. They also exhibited increased permeability, and lower germination capacities under osmotic and salt stress. AtMYB9 and AtMYB107 appear to synchronize the transcriptional induction of aliphatic and aromatic monomer biosynthesis and transport and suberin polymerization in the seed outer integument layer. Collectively, our findings establish a regulatory system controlling developmentally deposited suberin, which likely differs from the one of stress-induced polymer assembly recognized to date. PMID:27604696
Vogel, Nicolas; Belisle, Rebecca A.; Hatton, Benjamin; ...
2013-07-31
A transparent coating that repels a wide variety of liquids, prevents staining, is capable of self-repair and is robust towards mechanical damage can have a broad technological impact, from solar cell coatings to self-cleaning optical devices. Here we employ colloidal templating to design transparent, nanoporous surface structures. A lubricant can be firmly locked into the structures and, owing to its fluidic nature, forms a defect-free, self-healing interface that eliminates the pinning of a second liquid applied to its surface, leading to efficient liquid repellency, prevention of adsorption of liquid-borne contaminants, and reduction of ice adhesion strength. We further show howmore » this method can be applied to locally pattern the repellent character of the substrate, thus opening opportunities to spatially confine any simple or complex fluids. The coating is highly defect-tolerant due to its interconnected, honeycomb wall structure, and repellency prevails after the application of strong shear forces and mechanical damage. The regularity of the coating allows us to understand and predict the stability or failure of repellency as a function of lubricant layer thickness and defect distribution based on a simple geometric model.« less
NASA Astrophysics Data System (ADS)
Zhou, Zhaoli
Cell-surface interaction is crucial in many cellular functions such as movement, growth, differentiation, proliferation and survival. In the present work, we have developed several strategies to design and prepare synthetic polymeric materials with selected cues to control cell attachment. To promote neuronal cell adhesion on the surfaces, biocompatible, non-adhesive PEG-based materials were modified with neurotransmitter acetylcholine functionalities to produce hydrogels with a range of porous structures, swollen states, and mechanical strengths. Mice hippocampal cells cultured on the hydrogels showed differences in number, length of processes and exhibited different survival rates, thereby highlighting the importance of chemical composition and structure in biomaterials. Similar strategies were used to prepare polymer brushes to assess how topographical cues influence neuronal cell behaviors. The brushes were prepared using the "grown from" method through surface-initiated atom transfer radical polymerization (SI-ATRP) reactions and further patterned via UV photolithography. Protein absorption tests and hippocampal neuronal cell culture of the brush patterns showed that both protein and neuronal cells can adhere to the patterns and therefore can be guided by the patterns at certain length scales. We also prepared functional polymers to discourage attachment of undesirable cells on the surfaces. For example, we synthesized PEG-perfluorinated alkyl amphiphilic surfactants to modify polystyrene-block-poly(ethylene-ran-butylene)- block-polyisoprene (SEBI or K3) triblock copolymers for marine antifouling/fouling release surface coatings. Initial results showed that the polymer coated surfaces can facilitate removal of Ulva sporelings on the surfaces. In addition, we prepared both bioactive and dual functional biopassive/bioactive antimicrobial coatings based on SEBI polymers. Incubating the polymer coated surfaces with gram-positive bacteria (S. aureus), gram-negative bacteria (E. coli) and marine bacteria (C. marina ) species demonstrated that, unlike biopassive surfaces, the dual functionality polymer coated surfaces can significantly reduce both live and dead cells, without killing the cells in the culture media. The knowledge gained from those studies offers opportunities for further modification and potential applications of those types of polymers in the future.
Space environmental effects on LDEF composites: A leading edge coated graphite epoxy panel
NASA Technical Reports Server (NTRS)
George, Pete E.; Dursch, Harry W.; Hill, Sylvester G.
1993-01-01
The electronics module cover for the leading edge (Row D 9) experiment M0003-8 was fabricated from T300 graphite/934 epoxy unidirectional prepreg tape in a (O(sub 2), +/- 45, O(sub 2), +/- 45, 90, 0)(sub s) layup. This 11.75 in x 16.75 in panel was covered with thermal control coatings in three of the four quadrants with the fourth quadrant uncoated. The composite panel experienced different thermal cycling extremes in each quadrant due to the different optical properties of the coatings and bare composite. The panel also experienced ultraviolet (UV) and atomic oxygen (AO) attack as well as micrometeoroid and space debris impacts. An AO reactivity of 0.99 x 10(exp -24) cm(sup 3)/atom was calculated for the bare composite based on thickness loss. The white urethane thermal control coatings (A276 and BMS 1060) prevented AO attack of the composite substrate. However, the black urethane thermal control coating (Z306) was severely eroded by AO, allowing some AO attack of the composite substrate. An interesting banding pattern on the AO eroded bare composite surface was investigated and found to match the dimensions of the graphite fiber tow widths as prepregged. Also, erosion depths were greater in the darker bands. Five micrometeoroid/space debris impacts were cross sectioned to investigate possible structural damage as well as impact/AO interactions. Local crushing and delaminations were found to some extent in all of the impacts. No signs of coating undercutting were observed despite the extensive AO erosion patterns seen in the exposed composite material at the impact sites. An extensive microcrack study was performed on the panel along with modeling of the thermal environment to estimate temperature extremes and thermal shock. The white coated composite substrate displayed almost no microcracking while the black coated and bare composite showed extensive microcracking. Significant AO erosion was seen in many of the cracks in the bare composite.
NASA Astrophysics Data System (ADS)
Luo, Xiaotao; Smith, Gregory M.; Sampath, Sanjay
2018-02-01
Adhesion of thermal spray (TS) coatings is an important system level property in coating design and application. Adhesive-based pull testing (ASTM C633) has long been used to evaluate coating/substrate bonding. However, this approach is not always suitable for high velocity spray coatings, for example, where adhesion strengths are routinely greater than the strength of the adhesive bonding agent used in the testing. In this work, a new approach has been proposed to evaluate the adhesion of TS coatings. A systematic investigation of the effects of substrate roughness on both the uniaxial tensile yield strength and traditional bond pull adhesive strength of HVOF Ni and Ni-5wt.%Al, as well as cold-sprayed Ni-coated laminates revealed a strong correlation between these two test methodologies for the respective materials and processes. This approach allows measurement of the adhesion response even where the adhesive method is not applicable, overcoming many of the issues in the traditional ASTM C633. Analysis of cracking patterns of the coatings after 10.5% strain was used to assess the adhesion and cohesion properties. The mechanisms which determine the load transfer between the substrate and the coating are also briefly discussed.
Gurunathan, Rajalakshmi; Van Emden, Bernard; Panchanathan, Sethuraman; Kumar, Sudhir
2004-01-01
Background Modern developmental biology relies heavily on the analysis of embryonic gene expression patterns. Investigators manually inspect hundreds or thousands of expression patterns to identify those that are spatially similar and to ultimately infer potential gene interactions. However, the rapid accumulation of gene expression pattern data over the last two decades, facilitated by high-throughput techniques, has produced a need for the development of efficient approaches for direct comparison of images, rather than their textual descriptions, to identify spatially similar expression patterns. Results The effectiveness of the Binary Feature Vector (BFV) and Invariant Moment Vector (IMV) based digital representations of the gene expression patterns in finding biologically meaningful patterns was compared for a small (226 images) and a large (1819 images) dataset. For each dataset, an ordered list of images, with respect to a query image, was generated to identify overlapping and similar gene expression patterns, in a manner comparable to what a developmental biologist might do. The results showed that the BFV representation consistently outperforms the IMV representation in finding biologically meaningful matches when spatial overlap of the gene expression pattern and the genes involved are considered. Furthermore, we explored the value of conducting image-content based searches in a dataset where individual expression components (or domains) of multi-domain expression patterns were also included separately. We found that this technique improves performance of both IMV and BFV based searches. Conclusions We conclude that the BFV representation consistently produces a more extensive and better list of biologically useful patterns than the IMV representation. The high quality of results obtained scales well as the search database becomes larger, which encourages efforts to build automated image query and retrieval systems for spatial gene expression patterns. PMID:15603586
Spontaneous formation of nanoparticle stripe patterns through dewetting
NASA Astrophysics Data System (ADS)
Huang, Jiaxing; Kim, Franklin; Tao, Andrea R.; Connor, Stephen; Yang, Peidong
2005-12-01
Significant advancement has been made in nanoparticle research, with synthetic techniques extending over a wide range of materials with good control over particle size and shape. A grand challenge is assembling and positioning the nanoparticles in desired locations to construct complex, higher-order functional structures. Controlled positioning of nanoparticles has been achieved in pre-defined templates fabricated by top-down approaches. A self-assembly method, however, is highly desirable because of its simplicity and compatibility with heterogeneous integration processes. Here we report on the spontaneous formation of ordered gold and silver nanoparticle stripe patterns on dewetting a dilute film of polymer-coated nanoparticles floating on a water surface. Well-aligned stripe patterns with tunable orientation, thickness and periodicity at the micrometre scale were obtained by transferring nanoparticles from a floating film onto a substrate in a dip-coating fashion. This facile technique opens up a new avenue for lithography-free patterning of nanoparticle arrays for various applications including, for example, multiplexed surface-enhanced Raman substrates and templated fabrication of higher-order nanostructures.
Application of DNA Machineries for the Barcode Patterned Detection of Genes or Proteins.
Zhou, Zhixin; Luo, Guofeng; Wulf, Verena; Willner, Itamar
2018-06-05
The study introduces an analytical platform for the detection of genes or aptamer-ligand complexes by nucleic acid barcode patterns generated by DNA machineries. The DNA machineries consist of nucleic acid scaffolds that include specific recognition sites for the different genes or aptamer-ligand analytes. The binding of the analytes to the scaffolds initiate, in the presence of the nucleotide mixture, a cyclic polymerization/nicking machinery that yields displaced strands of variable lengths. The electrophoretic separation of the resulting strands provides barcode patterns for the specific detection of the different analytes. Mixtures of DNA machineries that yield, upon sensing of different genes (or aptamer ligands), one-, two-, or three-band barcode patterns are described. The combination of nucleic acid scaffolds acting, in the presence of polymerase/nicking enzyme and nucleotide mixture, as DNA machineries, that generate multiband barcode patterns provide an analytical platform for the detection of an individual gene out of many possible genes. The diversity of genes (or other analytes) that can be analyzed by the DNA machineries and the barcode patterned imaging is given by the Pascal's triangle. As a proof-of-concept, the detection of one of six genes, that is, TP53, Werner syndrome, Tay-Sachs normal gene, BRCA1, Tay-Sachs mutant gene, and cystic fibrosis disorder gene by six two-band barcode patterns is demonstrated. The advantages and limitations of the detection of analytes by polymerase/nicking DNA machineries that yield barcode patterns as imaging readout signals are discussed.
Liberio, Michelle S.; Sadowski, Martin C.; Soekmadji, Carolina; Davis, Rohan A.; Nelson, Colleen C.
2014-01-01
Weak cell-surface adhesion of cell lines to tissue culture surfaces is a common problem and presents technical limitations to the design of experiments. To overcome this problem, various surface coating protocols have been developed. However, a comparative and precise real-time measurement of their impact on cell behavior has not been conducted. The prostate cancer cell line LNCaP, derived from a patient lymph node metastasis, is a commonly used model system in prostate cancer research. However, the cells’ characteristically weak attachment to the surface of tissue culture vessels and cover slips has impeded their manipulation and analysis and use in high throughput screening. To improve the adherence of LNCaP cells to the culture surface, we compared different coating reagents (poly-l-lysine, poly-l-ornithine, collagen type IV, fibronectin, and laminin) and culturing conditions and analyzed their impact on cell proliferation, adhesion, morphology, mobility and gene expression using real-time technologies. The results showed that fibronectin, poly-l-lysine and poly-l-ornithine improved LNCaP cells adherence and provoked cell morphology alterations, such as increase of nuclear and cellular area. These coating reagents also induced a higher expression of F-actin and reduced cell mobility. In contrast, laminin and collagen type IV did not improve adherence but promoted cell aggregation and affected cell morphology. Cells cultured in the presence of laminin displayed higher mobility than control cells. All the coating conditions significantly affected cell viability; however, they did not affect the expression of androgen receptor-regulated genes. Our comparative findings provide important insight for the selection of the ideal coating reagent and culture conditions for the cancer cell lines with respect to their effect on proliferation rate, attachment, morphology, migration, transcriptional response and cellular cytoskeleton arrangement. PMID:25375165
Sphene ceramics for orthopedic coating applications: an in vitro and in vivo study.
Ramaswamy, Yogambha; Wu, Chengtie; Dunstan, Colin R; Hewson, Benjamin; Eindorf, Tanja; Anderson, Gail I; Zreiqat, Hala
2009-10-01
The host response to titanium alloy (Ti-6Al-4V) is not always favorable as a fibrous layer may form at the skeletal tissue-device interface, causing aseptic loosening. Recently, sphene (CaTiSiO(5)) ceramics were developed by incorporating Ti in the Ca-Si system, and found to exhibit improved chemical stability. The aim of this study is to evaluate the in vitro response of human osteoblast-like cells, human osteoclasts and human microvascular endothelial cells to sphene ceramics and determine whether coating Ti-6Al-4V implants with sphene enhances anchorage to surrounding bone. The study showed that sphene ceramics support human osteoblast-like cell attachment with organized cytoskeleton structure and express increased mRNA levels of osteoblast-related genes. Sphene ceramics were able to induce the differentiation of monocytes to form functional osteoclasts with the characteristic features of f-actin and alpha(v)beta(3) integrin, and express osteoclast-related genes. Human endothelial cells were also able to attach and express the endothelial cell markers ZO-1 and VE-Cadherin when cultured on sphene ceramics. Histological staining, enzyme histochemistry and immunolabelling were used for identification of mineralized bone and bone remodelling around the coated implants. Ti-6Al-4V implants coated with sphene showed new bone formation and filled the gap between the implants and existing bone in a manner comparable to that of the hydroxyapatite coatings used as control. The new bone was in direct contact with the implants, whereas fibrous tissue formed between the bone and implant with uncoated Ti-6Al-4V. The in vivo assessment of sphene-coated implants supports our in vitro observation and suggests that they have the ability to recruit osteogenic cells, and thus support bone formation around the implants and enhance osseointegration.
Heterogeneity in pepper isolates of cucumber mosaic virus
Rodriguez-Alvarado, G.; Kurath, G.; Dodds, J.A.
1995-01-01
Twenty-four cucumber mosaic cucumovirus (CMV) field isolates from pepper crops in Cali-fornia were characterized and compared by nucleic acid hybridization subgrouping, virion electrophoresis, and biological effects in several hosts. Isolates, belonging to subgroup I or subgroup II, were found that induced severe symptoms in mechanically inoculated bell pep-pers. Only two isolates, both from subgroup II, were mild. A group of 19 isolates collected from a single field were all in subgroup II and appeared identical by virion electrophoresis, but they exhibited varying degrees of symptom severity in peppers. As a more detailed indicator of heterogeneity, these 19 isolates were examined by RNase protection assays to delect sequence variation in the coat protein gene region of their genomes. The patterns of bands observed were complex and a high degree of genomic heterogeneity was detected between isolates, with no apparent correlation to symptomatology in bell pepper.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gonsalves, C.; Xue, B.; Yepes, M.
1994-03-01
A single regeneration procedure using cotyledon examples effectively regenerated five commercially grown muskmelon cultivars. This regeneration scheme was used to facilitate gene transfers using either Agrobacterium tumefaciens or microprojectile bombardment methods. In both cases, the transferred genes were from the T-DNA region of the binary vector plasmid pGA482GG/cp cucumber mosaic virus-white leaf strain (CMV-WL), which contains genes that encode neomycin phosphotransferase II (NPT II), [beta]-glucuronidase (GUS), and the CMV-WL coat protein (CP). Explants treated with pGA482GG/cpCMV-WL regenerated shoots on Murashige and Skoog medium containing 4.4 [mu]m 6-benzylaminopurine (BA), kanamycin (Km) at 150 mg[center dot]liter[sup [minus]1] and carbenicillin (Cb) at 500more » mg[center dot]liter[sup [minus]1]. The authors' comparison of A. tumefaciens- and microprojectile-mediated gene transfer procedures shows that both methods effectively produce nearly the same percentage of transgenic plants. R[sub 0] plants were first tested for GUS or NPT II expression, then the polymerase chain reaction (PCR) and other tests were used to verify the transfer of the NPT II, GUS, and CMV-WL CP genes.« less
Gene transfer of Hodgkin cell lines via multivalent anti-CD30 scFv displaying bacteriophage.
Chung, Yoon-Suk A; Sabel, Katja; Krönke, Martin; Klimka, Alexander
2008-04-16
The display of binding ligands, such as recombinant antibody fragments, on the surface of filamentous phage makes it possible to specifically attach these phage particles to target cells. After uptake of the phage, their internal single-stranded DNA is processed by the host cell, which allows transient expression of an encoded eukaryotic gene cassette. This opens the possibility to use bacteriophage as vectors for targeted gene therapy, although the transduction efficiency is very low. Here we demonstrate the display of an anti-CD30 single chain variable fragment fused to the major coat protein pVIII on the surface of bacteriophage. These phage particles showed an improved binding and transduction efficiency of CD30 positive Hodgkin-lymphoma cells, compared to bacteriophage with the anti-CD30 single chain variable fragment fused to the minor coat protein pIII. We can conclude from the results that the postulated multivalency of the anti-CD30-pVIII displaying bacteriophage combined with disseminated display of the anti-CD30 scFv on the whole particle surface is responsible for the improved gene transfer rate. These results mark an important step towards the use of phage particles as a cheap and safe gene transfer vehicle for the gene delivery of the desired target cells via their specific surface receptors.
Feldhoff, A; Wetzel, T; Peters, D; Kellner, R; Krczal, G
1998-01-01
With the introduction of cutting-grown Petunia x hybrida plants on the European market, a new potyvirus which showed no serological reaction with antisera against any other potyviruses infecting petunias was discovered. Infected leaves contained flexuous rod-shaped virus particles of 750-800 nm in length and inclusion bodies (pinwheel structures) typical for potyviruses in ultrathin leaf sections. The purified coat protein with a Mr of approximately 36 kDa could be detected in Western immunoblots with a specific antibody to the coat protein of the petunia-infecting virus. The 3' end of the viral genome encompassing the 3' non-coding region, the coat protein gene, and part of the NIb gene was amplified from infected leaf material by IC/PCR using degenerate and specific primers. Sequences of PCR-generated cDNA clones were compared to other known sequences of potyviruses. Maximum homology of 56% was found in the 3' non-coding region between the petunia isolate and other potyviruses. A maximum homology of 69% was found between the amino acid sequence of the coat protein of the petunia isolate and corresponding sequences of other potyviruses. These data indicate that the petunia-infecting virus is a previously undescribed potyvirus and the name petunia flower mottle virus (PetFMV) is suggested.
Thermally induced delay and reversal of liquid film dewetting on chemically patterned surfaces.
Kalpathy, Sreeram K; Francis, Lorraine F; Kumar, Satish
2013-10-15
A thin liquid film resting on a solid substrate that is heated or cooled from below experiences surface tension gradients, which lead to Marangoni flows. We explore the behavior of such a film on a chemically patterned substrate which drives film dewetting in order to determine how surface patterning and applied temperature gradients can be designed to influence the behavior of thin-film coatings. A nonlinear partial differential equation for the film height based on lubrication theory is solved numerically for a broad range of problem parameters. Uniform cooling of the substrate is found to significantly delay dewetting that is driven by wettability gradients. Uniform heating speeds up dewetting but can destroy the near-perfect templating imposed by the surface patterning. However, localized heating and cooling together can accelerate dewetting while maintaining templating quality. Localized heating and cooling can also be used to drive liquid onto areas that it would dewet from in the absence of heating. Overall, these results indicate that applied temperature gradients can significantly influence dewetting driven by surface patterning, and suggest strategies for the creation of spatially patterned thin-film coatings and flow control in microfluidic devices. Copyright © 2013 Elsevier Inc. All rights reserved.
NASA Astrophysics Data System (ADS)
Hua, Feng
Nanoparticles are exciting materials because they exhibit unique electronic, catalytic, and optical properties. As a novel and promising nanobuilding block, it attracts considerable research efforts in its integration into a wide variety of thin film devices. Nanoparticles were adsorbed onto the substrate with layer-by-layer self-assembly which becomes of great interest due to its suitability in colloid particle assembly. Without extremely high temperatures and sophisticated equipment, molecularly organized films in an exactly pre-designed order can grow on almost all the substrates in nature. Two approaches generating spatially separated patterns comprised of nanoparticles are demonstrated, as well as two approaches patterning more than one type of nonoparticle on a silicon wafer. The structure of the thin film patterned by these approaches are analyzed and considered suitable to the thin film device. Finally, the combination of lithography and layer-by-layer (lbl) self-assembly is utilized to realize the microelectronic device with functional nonoparticles. The lbl self-assembly is the way to coat the nonoparticles and the lighography to pattern them. Based on the coating and patterning technique, a MOS-capacitor, a MOS field-effect-transistor and magnetic thin film cantilever are fabricated.
Genetic and pharmacological reactivation of the mammalian inactive X chromosome
Bhatnagar, Sanchita; Zhu, Xiaochun; Ou, Jianhong; Lin, Ling; Chamberlain, Lynn; Zhu, Lihua J.; Wajapeyee, Narendra; Green, Michael R.
2014-01-01
X-chromosome inactivation (XCI), the random transcriptional silencing of one X chromosome in somatic cells of female mammals, is a mechanism that ensures equal expression of X-linked genes in both sexes. XCI is initiated in cis by the noncoding Xist RNA, which coats the inactive X chromosome (Xi) from which it is produced. However, trans-acting factors that mediate XCI remain largely unknown. Here, we perform a large-scale RNA interference screen to identify trans-acting XCI factors (XCIFs) that comprise regulators of cell signaling and transcription, including the DNA methyltransferase, DNMT1. The expression pattern of the XCIFs explains the selective onset of XCI following differentiation. The XCIFs function, at least in part, by promoting expression and/or localization of Xist to the Xi. Surprisingly, we find that DNMT1, which is generally a transcriptional repressor, is an activator of Xist transcription. Small-molecule inhibitors of two of the XCIFs can reversibly reactivate the Xi, which has implications for treatment of Rett syndrome and other dominant X-linked diseases. A homozygous mouse knockout of one of the XCIFs, stanniocalcin 1 (STC1), has an expected XCI defect but surprisingly is phenotypically normal. Remarkably, X-linked genes are not overexpressed in female Stc1−/− mice, revealing the existence of a mechanism(s) that can compensate for a persistent XCI deficiency to regulate X-linked gene expression. PMID:25136103
Moon, Ju Yeon; Lee, Jeong Hee; Oh, Chang-Sik; Kang, Hong-Gu; Park, Jeong Mee
2016-12-01
HRT is a plant coiled-coil, nucleotide-binding and leucine-rich repeat (CC-NB-LRR) disease resistance protein that triggers the hypersensitive response (HR) on recognition of Turnip crinkle virus (TCV) coat protein (CP). The molecular mechanism and significance of HR-mediated cell death for TCV resistance have not been fully elucidated. To identify the genes involved in HRT/TCV CP-mediated HR in Nicotiana benthamiana, we performed virus-induced gene silencing (VIGS) of 459 expressed sequence tags (ESTs) of pathogen-responsive Capsicum annuum genes. VIGS of CaBLP5, which encodes an endoplasmic reticulum (ER)-associated immunoglobulin-binding protein (BiP), silenced NbBiP4 and NbBiP5 and significantly reduced HRT-mediated HR. The induction of ER stress-responsive genes and the accumulation of ER-targeted BiPs in response to HRT-mediated HR suggest that ER is involved in HR in N. benthamiana. BiP4/5 silencing significantly down-regulated HRT at the mRNA and protein levels, and affected SGT1 and HSP90 expression. Co-expression of TCV CP in BiP4/5-silenced plants completely abolished HRT induction. Transient expression of TCV CP alone induced selected ER stress-responsive gene transcripts only in Tobacco rattle virus (TRV)-infected plants, and most of these genes were induced by HRT/TCV CP, except for bZIP60, which was induced specifically in response to HRT/TCV CP. TCV CP-mediated induction of ER stress-responsive genes still occurred in BiP4/5-silenced plants, but HRT/TCV CP-mediated induction of these genes was defective. Tunicamycin, a chemical that inhibits protein N-glycosylation, inhibited HRT-mediated HR, suggesting that ER has a role in HR regulation. These results indicate that BiP and ER, which modulate pattern recognition receptors in innate immunity, also regulate R protein-mediated resistance. © 2016 BSPP and John Wiley & Sons Ltd.
Molecular patterns of X chromosome-linked color vision genes among 134 menof European ancestry
DOE Office of Scientific and Technical Information (OSTI.GOV)
Drummond-Borg, M.; Deeb, S.S.; Motulsky, A.G.
1989-02-01
The authors used Southern blot hybridization to study X chromosome-linked color vision genes encoding the apoproteins of red and green visual pigments in 134 unselected Caucasian men. One hundred and thirteen individuals (84.3%) had a normal arrangement of their color vision pigment genes. All had one red pigment gene; the number of green pigment genes ranged from one to five with a mode of two. The frequency of molecular genotypes indicative of normal color vision (84.3%) was significantly lower than had been observed in previous studies of color vision phenotypes. Color vision defects can be due to deletions of redmore » or green pigment genes or due to formation of hybrid genes comprising portions of both red and green pigment genes. Characteristic anomalous patterns were seen in 15 (11.2%) individuals: 7 (5.2%) had patterns characteristic of deuteranomaly, 2 (1.5%) had patterns characteristic of deuteranopia, and 6 (4.5%) had protan patterns. Previously undescribed hybrid gene patterns consisting of both green and red pigment gene fragments in addition to normal red and green genes were observed in another 6 individuals (4.5%). Thus, DNA testing detected anomalous color vision pigment genes at a higher frequency than expected from phenotypic color vision tests.« less
Jang, Hongje; Kim, Dong-Eun; Min, Dal-Hee
2015-06-17
Hollow Au-Ag bimetallic nanoshell possessing hydrophobic interior space and hydrophilic exterior surface was prepared and its application as a chemo-thermo-gene therapeutic agent based on its high payload of multiple drugs having different water solubility was demonstrated. The multifunctional drug delivery system is based on the hydrophobic interior created by the self-assembled monolayer (SAM) of hexanethiol onto the inner surface of the hollow metallic nanoshells whereas the outer surface was mostly coated by hydrophilic biocompatible polymer. The nanoshells having surface environment modified by hexanethiol SAMs provided high capacity both for hydrophilic DNAzyme (Dz) to induce gene silencing and for hydrophobic SN38 (7-ethyl-10-hydroxycamptothecin), anticancer drug. The release of the loaded Dz and SN38 was independently triggered by an acidic environment and by photothermal temperature elevation upon irradiation, respectively. The chemo-thermo-gene multitherapy based on the present nanoshells having modified surface environment showed high efficacy in quantitative cell-based assays using Huh7 human liver cell containing hepatitis C viral NS3 gene replicon RNA.
Gene Activated Titanium Surfaces Promote In Vitro Osteogenesis
Atluri, Keerthi; Lee, Joun; Seabold, Denise; Elangovan, Satheesh; Salem, Aliasger K.
2016-01-01
Commercially pure titanium (CpTi) and its alloys possess favorable mechanical and biological properties for use as implants in orthopedics and dentistry. However, failures in osseointegration still exist and are common in select individuals with risk factors such as smoking. Therefore, in this study, a proposal was made to enhance the potential of CpTi discs for osseointegration by coating their surfaces with nanoplexes comprising polyethyleneimine (PEI) and plasmid DNA encoding bone morphogenetic protein-2 (pBMP-2). The nanoplexes were characterized for size and surface charge at a range of N/P ratios. CpTi discs were surface characterized for morphology and composition before and after nanoplex coating using scanning electron microscopy (SEM), atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS) and X-ray powder diffraction (XRD). The cytotoxicity and transfection ability of CpTi discs coated with nanoplexes of varying N/P ratios in human bone marrow derived mesenchymal stem cells (BMSCs) was measured via MTS assays and flow cytometry, respectively. The CpTi discs coated with nanoplexes prepared at an N/P ratio of 10 (N/P-10) were considered optimal, resulting in 75% cell viability and 14% transfection efficiency. ELISA results demonstrated a significant enhancement in BMP-2 protein secretion by BMSCs 7 days post-treatment with CpTi discs coated with PEI/pBMP-2 nanoplexes (N/P-10), compared to the controls. Real time PCR data demonstrated that the BMSCs treated with PEI/pBMP-2 nanoplex coated CpTi discs resulted in an enhancement of runx-2, alkaline phosphatase and osteocalcin gene expressions on day 7, post-treatment. In addition, these BMSCs demonstrated enhanced calcium deposition on day 30 post-treatment as determined by qualitative (alizarin red staining) and quantitative (atomic absorption spectroscopy) assays. Thus, from all the above data it can be concluded that PEI/pBMP-2 nanoplex (N/P-10) coated CpTi discs have the potential to induce osteogenesis and enhance osseointegration. PMID:27706263
NASA Astrophysics Data System (ADS)
Fu, Yao; Zhang, Xian-Cheng; Sui, Jian-Feng; Tu, Shan-Tung; Xuan, Fu-Zhen; Wang, Zheng-Dong
2015-04-01
The aim of this paper was to develop a one-step in situ method to synthesize the TiN reinforced Al metallic matrix composite coatings on Ti6Al4V alloy. In this method, the Al powder and nitrogen gas were simultaneously fed into feeding nozzle during a laser nitriding process. The microstructure, microhardness and sliding wear resistance of TiN/Al coatings synthesized at different laser powers in laser nitriding were investigated. Results showed that the crack- and pore-free coatings can be made through the proposed method. However, the morphologies and distribution of TiN dendrites and wear resistance of coatings were strongly dependent on laser power used in nitriding. With increasing the laser power, the amount and density of massive TiN dendritic structure in the coating decreased and the elongated and narrow dendrites increased, leading to the increment of wear resistance of coating. When the laser power is high, the convectional flow pattern of the melt pool can be seen near the bottom of pool.
Broadband angle-independent antireflection coatings on nanostructured light trapping solar cells
NASA Astrophysics Data System (ADS)
Vázquez-Guardado, Abraham; Boroumand, Javaneh; Franklin, Daniel; Chanda, Debashis
2018-03-01
Backscattering from nanostructured surfaces greatly diminishes the efficacy of light trapping solar cells. While the analytical design of broadband, angle-independent antireflection coatings on nanostructured surfaces proved inefficient, numerical optimization proves a viable alternative. Here, we numerically design and experimentally verify the performance of single and bilayer antireflection coatings on a 2D hexagonal diffractive light trapping pattern on crystalline silicon substrates. Three well-known antireflection coatings, aluminum oxide, silicon nitride, and silicon oxide, which also double as high-quality surface passivation materials, are studied in the 400-1000 nm band. By varying thickness and conformity, the optimal parameters that minimize the broadband total reflectance (specular and scattering) from the nanostructured surface are obtained. The design results in a single-layer antireflection coating with normal-angle wavelength-integrated reflectance below 4% and a bilayer antireflection coating demonstrating reflection down to 1.5%. We show experimentally an angle-averaged reflectance of ˜5.2 % up to 60° incident angle from the optimized bilayer antireflection-coated nanostructured surface, paving the path toward practical implementation of the light trapping solar cells.
Synthesis of superparamagnetic silica-coated magnetite nanoparticles for biomedical applications
NASA Astrophysics Data System (ADS)
Kaur, Navjot; Chudasama, Bhupendra
2015-05-01
Multifunctional superparamagnetic iron oxide nanoparticles (SPIONs) coated with silica are widely researched for biomedical applications such as magnetic resonance imaging, tissue repair, cell separation, hyperthermia, drug delivery, etc. In this article synthesis of magnetite (Fe3O4) nanoparticles and their coating with SiO2 is reported. Fe3O4 nanoparticles were synthesized by chemical co-precipitation and it was coated with silica by hydrolysis and condensation of tetraethylorthosilicate. XRD, FTIR, TEM and VSM techniques were used to characterize bare and coated nanoparticles. Results indicated that the average size of SPIONS was 8.4 nm. X-ray diffraction patterns of silica coated SPIONS were identical to that of SPIONS confirming the inner spinal structure of SPIONS. FTIR results confirmed the binding of silica with the magnetite and the formation of the silica shell around the magnetite core. Magnetic properties of SPIONS and silica coated SPIONS are determined by VSM. They are superparamagnetic. The major conclusion drawn from this study is that the synthesis route yields stable, non-aggregated magnetite-silica core-shell nanostructures with tailored morphology and excellent magnetic properties.
Fabrication of a Flexible Amperometric Glucose Sensor Using Additive Processes
Du, Xiaosong; Durgan, Christopher J.; Matthews, David J.; Motley, Joshua R.; Tan, Xuebin; Pholsena, Kovit; Árnadóttir, Líney; Castle, Jessica R.; Jacobs, Peter G.; Cargill, Robert S.; Ward, W. Kenneth; Conley, John F.; Herman, Gregory S.
2015-01-01
This study details the use of printing and other additive processes to fabricate a novel amperometric glucose sensor. The sensor was fabricated using a Au coated 12.7 μm thick polyimide substrate as a starting material, where micro-contact printing, electrochemical plating, chloridization, electrohydrodynamic jet (e-jet) printing, and spin coating were used to pattern, deposit, chloridize, print, and coat functional materials, respectively. We have found that e-jet printing was effective for the deposition and patterning of glucose oxidase inks with lateral feature sizes between ~5 to 1000 μm in width, and that the glucose oxidase was still active after printing. The thickness of the permselective layer was optimized to obtain a linear response for glucose concentrations up to 32 mM and no response to acetaminophen, a common interfering compound, was observed. The use of such thin polyimide substrates allow wrapping of the sensors around catheters with high radius of curvature ~250 μm, where additive and microfabrication methods may allow significant cost reductions. PMID:26634186
DOE Office of Scientific and Technical Information (OSTI.GOV)
Rack, Alexander, E-mail: alexander.rack@esrf.fr; Vivo, Amparo; Morawe, Christian
2016-07-27
Multilayer mirrors present an attractive alternative for reflective hard X-ray monochromators due to their increased bandwidth compared with crystal-based systems. An issue remains the strong modulations in the reflected beam profile, i.e. an irregular stripe pattern. This is a major problem for micro-imaging applications, where multilayer-based monochromators are frequently employed to deliver higher photon flux density. A subject of particular interest is how to overcome beam profile modifications, namely the stripe patterns, induced by the reflection on a multilayer. For multilayer coatings in general it is known that the substrate and its surface quality significantly influence the performance of suchmore » kind of mirrors as the coating reproduces to a certain degree roughness and shape of the substrate. Our studies have shown that modified coatings can significantly change the impact of the multilayer reflection on the beam profile. We will present recent results as well as a critical review.« less
USDA-ARS?s Scientific Manuscript database
Here we reported a previously-undescribed coat color phenotype in Holstein cattle. Larson Blue Holsteins, located on a dairy in south Florida, exhibit a coloration pattern that is similar to that of black and white or red and white Holsteins except that, instead of being black or red, darker region...
Magnetic field dependence of the current flowing in the spin-coated chlorophyll thin films
NASA Astrophysics Data System (ADS)
Aji, J. R. P.; Kusumandari; Purnama, B.
2018-03-01
The magnetic dependence of the current flowing in the spin coated chlorophyll films on a patterned Cu PCB substrate has been presented. Chlorophyll was isolated from Spirulina sp and deposited by spin coated methods. The reducing of current by the change of magnetic field (magneto conductance effect) was performed by inducing the magnetic field parallel to the inplane of film at room temp. The magnetoconductance ratio decreases as the increase of voltage. It was indicated that the origin of carrier charge in chlorophyll films should be different with the carrier charge injection (electron).
Guarino, Gaetano; Rastrelli, Federico; Scrimin, Paolo; Mancin, Fabrizio
2012-05-02
Gd(3+) ions, once bound to the monolayer of organic molecules coating the surface of gold nanoparticles, produce a paramagnetic relaxation enhancement (PRE) that broadens and eventually cancels the signals of the nuclear spins located nearby (within 1.6 nm distance). In the case of nanoparticles coated with mixed monolayers, the signals arising from the different coating molecules experience different PRE, depending on their distance from the binding site. As a consequence, observation of the signal broadening patterns provides direct information on the monolayer organization. © 2012 American Chemical Society
NASA Astrophysics Data System (ADS)
Bongova, M.; Urgela, Stanislav
1999-07-01
Physicoacoustical properties of wood influenced by surface coating are studied by modal analysis. Resonant spruce plates were coated by stain, nitrocellulose varnish, special violin paint and shellac. The modal testing was performed by electronic speckle pattern interferometry. For this purpose, equipment called VIBROVIZER was used. The collected values of physicoacoustical characteristics (density, Young's modulus, acoustic constant) were compared using the graphic plots of data. The 3D plots help to evaluate wooden plates from a viewpoint of the quality control. This fact offers new opportunity for musical instrument manufacturers.
Discovering gene annotations in biomedical text databases
Cakmak, Ali; Ozsoyoglu, Gultekin
2008-01-01
Background Genes and gene products are frequently annotated with Gene Ontology concepts based on the evidence provided in genomics articles. Manually locating and curating information about a genomic entity from the biomedical literature requires vast amounts of human effort. Hence, there is clearly a need forautomated computational tools to annotate the genes and gene products with Gene Ontology concepts by computationally capturing the related knowledge embedded in textual data. Results In this article, we present an automated genomic entity annotation system, GEANN, which extracts information about the characteristics of genes and gene products in article abstracts from PubMed, and translates the discoveredknowledge into Gene Ontology (GO) concepts, a widely-used standardized vocabulary of genomic traits. GEANN utilizes textual "extraction patterns", and a semantic matching framework to locate phrases matching to a pattern and produce Gene Ontology annotations for genes and gene products. In our experiments, GEANN has reached to the precision level of 78% at therecall level of 61%. On a select set of Gene Ontology concepts, GEANN either outperforms or is comparable to two other automated annotation studies. Use of WordNet for semantic pattern matching improves the precision and recall by 24% and 15%, respectively, and the improvement due to semantic pattern matching becomes more apparent as the Gene Ontology terms become more general. Conclusion GEANN is useful for two distinct purposes: (i) automating the annotation of genomic entities with Gene Ontology concepts, and (ii) providing existing annotations with additional "evidence articles" from the literature. The use of textual extraction patterns that are constructed based on the existing annotations achieve high precision. The semantic pattern matching framework provides a more flexible pattern matching scheme with respect to "exactmatching" with the advantage of locating approximate pattern occurrences with similar semantics. Relatively low recall performance of our pattern-based approach may be enhanced either by employing a probabilistic annotation framework based on the annotation neighbourhoods in textual data, or, alternatively, the statistical enrichment threshold may be adjusted to lower values for applications that put more value on achieving higher recall values. PMID:18325104
Discovering gene annotations in biomedical text databases.
Cakmak, Ali; Ozsoyoglu, Gultekin
2008-03-06
Genes and gene products are frequently annotated with Gene Ontology concepts based on the evidence provided in genomics articles. Manually locating and curating information about a genomic entity from the biomedical literature requires vast amounts of human effort. Hence, there is clearly a need forautomated computational tools to annotate the genes and gene products with Gene Ontology concepts by computationally capturing the related knowledge embedded in textual data. In this article, we present an automated genomic entity annotation system, GEANN, which extracts information about the characteristics of genes and gene products in article abstracts from PubMed, and translates the discoveredknowledge into Gene Ontology (GO) concepts, a widely-used standardized vocabulary of genomic traits. GEANN utilizes textual "extraction patterns", and a semantic matching framework to locate phrases matching to a pattern and produce Gene Ontology annotations for genes and gene products. In our experiments, GEANN has reached to the precision level of 78% at therecall level of 61%. On a select set of Gene Ontology concepts, GEANN either outperforms or is comparable to two other automated annotation studies. Use of WordNet for semantic pattern matching improves the precision and recall by 24% and 15%, respectively, and the improvement due to semantic pattern matching becomes more apparent as the Gene Ontology terms become more general. GEANN is useful for two distinct purposes: (i) automating the annotation of genomic entities with Gene Ontology concepts, and (ii) providing existing annotations with additional "evidence articles" from the literature. The use of textual extraction patterns that are constructed based on the existing annotations achieve high precision. The semantic pattern matching framework provides a more flexible pattern matching scheme with respect to "exactmatching" with the advantage of locating approximate pattern occurrences with similar semantics. Relatively low recall performance of our pattern-based approach may be enhanced either by employing a probabilistic annotation framework based on the annotation neighbourhoods in textual data, or, alternatively, the statistical enrichment threshold may be adjusted to lower values for applications that put more value on achieving higher recall values.
Halsas, M; Ervasti, P; Veski, P; Jürjenson, H; Marvola, M
1998-01-01
This paper deals with press-coated modified release tablets in which the drug dose is situated in the core or is divided between the core and the coat. The coat contains polymer (sodium alginate or hydroxypropylmethyl cellulose, HPMC) to control drug release. The main objective was to investigate how the pharmacokinetic profile of the model drug could be modified by altering the proportion of the drug between the core and the coat. The effect of the amount of the polymer in the coat was also studied. Bioavailability tests were carried out on healthy volunteers. In the absorption curves of the tablets containing 50%, 67% and 80% of the drug in the core and 180 mg HPMC in the coat a bimodal profile was observed. No bimodal release pattern in the in vitro dissolution studies was found. If the whole dose was incorporated in the core the absorption curve has only one clear t(max) value at about 10 h. Doubling the amount of HPMC in the coat dramatically decreased drug absorption. It was concluded that, if a slightly reduced t(max)-value was required, the viscosity grade of HPMC used should be lowered.
NASA Astrophysics Data System (ADS)
Zheng, Jie; Li, Ling; Chen, Weidong
2015-12-01
The bottom anti-reflective coating (BARC) material can enhance the resolution of the nanopatterns structures in laser interference lithography process. In this study, WIDE-B ARC material was investigated to confirm the reduction of the vertical standing wave which leads to defect of nanopatterns. And the critical dimension (CD) of 100 nm L/S patterns with and without the application of BARC material was fabricated by laser interference lithography technology. The compared results showed that BARC can effectively reduce CD swing and obtain more uniform nanopatterns. Meanwhile, we also verified the influence of cured temperature and film thickness of BARC on the uniformity of nanopatterns.
Wing patterning gene redefines the mimetic history of Heliconius butterflies.
Hines, Heather M; Counterman, Brian A; Papa, Riccardo; Albuquerque de Moura, Priscila; Cardoso, Marcio Z; Linares, Mauricio; Mallet, James; Reed, Robert D; Jiggins, Chris D; Kronforst, Marcus R; McMillan, W Owen
2011-12-06
The mimetic butterflies Heliconius erato and Heliconius melpomene have undergone parallel radiations to form a near-identical patchwork of over 20 different wing-pattern races across the Neotropics. Previous molecular phylogenetic work on these radiations has suggested that similar but geographically disjunct color patterns arose multiple times independently in each species. The neutral markers used in these studies, however, can move freely across color pattern boundaries, and therefore might not represent the history of the adaptive traits as accurately as markers linked to color pattern genes. To assess the evolutionary histories across different loci, we compared relationships among races within H. erato and within H. melpomene using a series of unlinked genes, genes linked to color pattern loci, and optix, a gene recently shown to control red color-pattern variation. We found that although unlinked genes partition populations by geographic region, optix had a different history, structuring lineages by red color patterns and supporting a single origin of red-rayed patterns within each species. Genes closely linked (80-250 kb) to optix exhibited only weak associations with color pattern. This study empirically demonstrates the necessity of examining phenotype-determining genomic regions to understand the history of adaptive change in rapidly radiating lineages. With these refined relationships, we resolve a long-standing debate about the origins of the races within each species, supporting the hypothesis that the red-rayed Amazonian pattern evolved recently and expanded, causing disjunctions of more ancestral patterns.
Use of Repeated Fluoropolymer Suspensions to Obtain Composite Electrochemical Coating Based on Zinc
NASA Astrophysics Data System (ADS)
Musikhina, T. A.; Zemtsova, E. A.; Fuks, C. L.
2017-11-01
This article deals with the issues of utilization of the waste products of fluoropolymers, namely, the suspensions of fluoroplasts that have lost their consumer properties. Such waste is recommended to be used as a filler of zinc coatings to provide increased corrosion resistance. Using the method of mathematical planning of the experiment, the authors establish the optimal compositions of galvanizing chloride-ammonium electrolytes to obtain the corrosion-resistant composite electrochemical coatings (CEC) of zinc-fluoropolymer. As a result, coatings with a finely crystalline structure were obtained differing in the distribution pattern on the surface of the samples and depending on the variation in the zinc concentration in the electrolytes. The samples of steel reinforcement with the zinc-fluoropolymer coating were tested on corrosion resistance. The increase of anticorrosive properties in CEC zinc-fluoropolymer and a slight decrease in microhardness were indicated.
One-step synthesis and patterning of aligned polymer nanowires on a substrate
Wang, Zhong L [Marietta, GA; Wang, Xudong [Atlanta, GA; Morber, Jenny R [Atlanta, GA; Liu, Jin [Danbury, CT
2011-11-08
In a method of making a polymer structure on a substrate a layer of a first polymer, having a horizontal top surface, is applied to a surface of the substrate. An area of the top surface of the polymer is manipulated to create an uneven feature that is plasma etched to remove a first portion from the layer of the first polymer thereby leaving the polymer structure extending therefrom. A light emitting structure includes a conductive substrate from which an elongated nanostructure of a first polymer extends. A second polymer coating is disposed about the nanostructure and includes a second polymer, which includes a material such that a band gap exists between the second polymer coating and the elongated nanostructure. A conductive material coats the second polymer coating. The light emitting structure emits light when a voltage is applied between the conductive substrate and the conductive coating.
In situ synthesis of hydroxyapatite coating by laser cladding.
Wang, D G; Chen, C Z; Ma, J; Zhang, G
2008-10-15
HA bioceramic coatings were synthesized on titanium substrate by laser cladding using cheap calcium carbonate and calcium hydrogen phosphate. The thermodynamic condition for synthesizing HA was calculated by software Matlab 5.0, the microstructure and phase analysis of laser clad HA bioceramic coatings were studied by electron probe microanalyser (EPMA), X-ray diffractometer (XRD) and transmission electron microscopy (TEM). The theoretical results show that the Gibbs free enthalpy for the synthesis of HA phase is satisfied, and the presence of HA phase in the clad coatings was then further verified by XRD and the selected area diffraction patterns. When the laser power is 600W and the scanning speed is 3.5mm/s, the compact HA bioceramic coatings were obtained, which have cellular dendritic structure and consist of the phases of HA, alpha-Ca(2)P(2)O(7), CaO and CaTiO(3).
The mammalian Ced-1 ortholog MEGF10/KIAA1780 displays a novel adhesion pattern
DOE Office of Scientific and Technical Information (OSTI.GOV)
Suzuki, Emiko; Nakayama, Manabu
2007-07-01
Ced-1 protein is a Caenorhabditis elegans cell surface receptor involved in phagocytosis of dead cells. The gene encoding the mammalian ortholog of Ced-1 is yet to be identified. Here, we describe a potential candidate: human MEGF10. MEGF10 has the overall domain organization of Ced-1, containing a signal peptide, a EMI domain, 17 atypical EGF-like repeats, a transmembrane domain, and a cytoplasmic domain with NPXY and YXXL motifs. MEGF10-EGFP fusion protein expressed in HEK293 cells produced an irregular, mosaic-like pattern on the surface of coated glass. Protruded MEGF10 bound tightly to the glass, in effect 'pinning' the cytoplasmic membrane firmly ontomore » the glass, thereby restricting cell motility. These cells also took on a flat appearance. Although MEGF10-EGFP localized throughout the cytoplasmic membrane, no MEGF10-EGFP was found in lamellipodia. The MEGF10-EGFP signal was surrounded by a 1-2-{mu}m-wide dark strip lacking EGFP. Expression analyses of various MEGF10 deletion mutants revealed that the irregular, mosaic-like adhesion pattern characteristic of MEGF10 family members is due to concerted interactions between the EMI and 17 atypical EGF-like domains. Co-culturing of MEGF10-EGFP-expressing cells with apoptotic cells revealed that MEGF10 protein accumulated around the contact region during engulfment of apoptotic cells.« less
NASA Astrophysics Data System (ADS)
Lu, Yu-Peng; Xiao, Gui-Yong; Li, Shi-Tong; Sun, Rui-Xue; Li, Mu-Sen
2006-01-01
The microstructural inhomogeneity in the plasma-sprayed hydroxyapatite (HA) coatings was characterized by using electron probe microanalyser (EPMA). A simple and artful method was developed to detect the interface characteristics. All the samples for observation were ground and polished along the direction parallel to the coating surfaces. The BSE images directly and clearly showed the inhomogeneity in the as-sprayed coatings with the amorphous regions being bright gray and crystalline regions being dark gray. X-ray diffractometer (XRD) patterns indicated that after immersion in deionized water for 20 days, bone-like apatite and α-Ca 2P 2O 7 precipitated on the polished surfaces of the as-sprayed HA coatings. The post-heat treatment could eliminate the microstructural inhomogeneity in the coatings. Only β-Ca 2P 2O 7 precipitated on the surfaces of the heat-treated HA coatings. The immersed samples were re-polished till tiny substrate was bared to investigate the effect of immersion on interface. It was shown that the immersion decreased the cohesive strength of the as-sprayed coatings. There were more and broader cracks in the splats that came into contact with the substrate and amorphous phase increased toward the coating-substrate interface. Post-heat treatment was proved to reduce the peeling off of coating during re-polishing operation. It was proposed that the distributions of amorphous phase and cracks in as-sprayed coatings are detrimental to coating properties and should be modified through improving the plasma spraying processing.
GEsture: an online hand-drawing tool for gene expression pattern search.
Wang, Chunyan; Xu, Yiqing; Wang, Xuelin; Zhang, Li; Wei, Suyun; Ye, Qiaolin; Zhu, Youxiang; Yin, Hengfu; Nainwal, Manoj; Tanon-Reyes, Luis; Cheng, Feng; Yin, Tongming; Ye, Ning
2018-01-01
Gene expression profiling data provide useful information for the investigation of biological function and process. However, identifying a specific expression pattern from extensive time series gene expression data is not an easy task. Clustering, a popular method, is often used to classify similar expression genes, however, genes with a 'desirable' or 'user-defined' pattern cannot be efficiently detected by clustering methods. To address these limitations, we developed an online tool called GEsture. Users can draw, or graph a curve using a mouse instead of inputting abstract parameters of clustering methods. GEsture explores genes showing similar, opposite and time-delay expression patterns with a gene expression curve as input from time series datasets. We presented three examples that illustrate the capacity of GEsture in gene hunting while following users' requirements. GEsture also provides visualization tools (such as expression pattern figure, heat map and correlation network) to display the searching results. The result outputs may provide useful information for researchers to understand the targets, function and biological processes of the involved genes.
SEEDSTICK is a Master Regulator of Development and Metabolism in the Arabidopsis Seed Coat
Paolo, Dario; Rueda-Romero, Paloma; Guerra, Rosalinda Fiorella; Battaglia, Raffaella; Rogachev, Ilana; Aharoni, Asaph; Kater, Martin M.; Caporali, Elisabetta; Colombo, Lucia
2014-01-01
The role of secondary metabolites in the determination of cell identity has been an area of particular interest over recent years, and studies strongly indicate a connection between cell fate and the regulation of enzymes involved in secondary metabolism. In Arabidopsis thaliana, the maternally derived seed coat plays pivotal roles in both the protection of the developing embryo and the first steps of germination. In this regard, a characteristic feature of seed coat development is the accumulation of proanthocyanidins (PAs - a class of phenylpropanoid metabolites) in the innermost layer of the seed coat. Our genome-wide transcriptomic analysis suggests that the ovule identity factor SEEDSTICK (STK) is involved in the regulation of several metabolic processes, providing a strong basis for a connection between cell fate determination, development and metabolism. Using phenotypic, genetic, biochemical and transcriptomic approaches, we have focused specifically on the role of STK in PA biosynthesis. Our results indicate that STK exerts its effect by direct regulation of the gene encoding BANYULS/ANTHOCYANIDIN REDUCTASE (BAN/ANR), which converts anthocyanidins into their corresponding 2,3-cis-flavan-3-ols. Our study also demonstrates that the levels of H3K9ac chromatin modification directly correlate with the active state of BAN in an STK-dependent way. This is consistent with the idea that MADS-domain proteins control the expression of their target genes through the modification of chromatin states. STK might thus recruit or regulate histone modifying factors to control their activity. In addition, we show that STK is able to regulate other BAN regulators. Our study demonstrates for the first time how a floral homeotic gene controls tissue identity through the regulation of a wide range of processes including the accumulation of secondary metabolites. PMID:25521508
Stachelek, S J; Song, C; Alferiev, I; Defelice, S; Cui, X; Connolly, J M; Bianco, R W; Levy, R J
2004-01-01
The present study investigated a novel approach for gene therapy of heart valve disease and vascular disorders. We formulated and characterized implantable polyurethane films that could also function as gene delivery systems through the surface attachment of replication defective adenoviruses using an anti-adenovirus antibody tethering mechanism. Our hypothesis was that we could achieve site-specific gene delivery to cells interacting with these polyurethane implants, and thereby demonstrate the potential for intravascular devices that could also function as gene delivery platforms for therapeutic vectors. Previous research by our group has demonstrated that polyurethane elastomers can be derivatized post-polymerization through a series of chemical reactions activating the hard segment amide groups with alkyl bromine residues, which can enable a wide variety of subsequent chemical modifications. Furthermore, prior research by our group investigating gene delivery intravascular stents has shown that collagen-coated balloon expandable stents can be configured with anti-adenovirus antibodies via thiol-based chemistry, and can then tether adenoviral vectors at doses that lead to high levels of localized arterial neointima expression, but with virtually no distal spread of vector. Thus, we sought to create two-device configurations for our investigations building on this previous research. (1) Polyurethane films coated with Type I collagen were thiol activated to permit covalent attachment of anti-adenovirus antibodies to enable gene delivery via vector tethering. (2) We also formulated polyurethane films with direct covalent attachment of anti-adenovirus antibodies to polyurethane hard segments derivatized with alkyl-thiol groups, thereby also enabling tethering of replication-defective adenoviruses. Both formulations demonstrated highly localized and efficient transduction in cell culture studies with rat arterial smooth muscle cells. In vivo experiments with collagen-coated polyurethane films investigated an abdominal aorta implant model in pigs using a button configuration that simulated the blood contacting environment of a vascular graft. One week explants of the collagen-coated polyurethane films demonstrated 14.3+/-2.5% of neointimal cells on the surface of the implant transduced with green fluorescent protein - adenovirus (AdGFP) vector loadings of 1 x 10(8) PFU. PCR studies demonstrated no detectable vector DNA in blood or distal organs. Similarly, polyurethane films with direct attachment of antivector antibodies to the surface were used in sheep pulmonary valve leaflet replacement studies, simulating the blood contacting environment of a prosthetic heart valve cusp. Polyurethane films with antibody tethered AdGFP vector (10(8) PFU) demonstrated 25.1+/-5.7% of attached cells transduced in these 1 week studies, with no detectable vector DNA in blood or distal organs. In vivo GFP expression was confirmed with immunohistochemistry. It is concluded that site-specific intravascular delivery of adenoviral vectors for gene therapy can be achieved with polyurethane implants utilizing the antivector antibody tethering mechanism.
Kim, Sae-Mi; Kang, Min-Ho; Kim, Hyoun-Ee; Lim, Ho-Kyung; Byun, Soo-Hwan; Lee, Jong-Ho; Lee, Sung-Mi
2017-12-01
The utility of a novel ceramic/polymer-composite coating with a micro-textured microstructure that would significantly enhance the functions of biodegradable Mg implants is demonstrated here. To accomplish this, bioactive hydroxyapatite (HA) micro-dots can be created by immersing a Mg implant with a micro-patterned photoresist surface in an aqueous solution containing calcium and phosphate ions. The HA micro-dots can then be surrounded by a flexible poly(l-lactic)-acid (PLLA) polymer using spin coating to form a HA/PLLA micro-textured coating layer. The HA/PLLA micro-textured coating layer showed an excellent corrosion resistance when it was immersed in a simulated body fluid (SBF) solution and good biocompatibility, which was assessed by in vitro cell tests. In addition, the HA/PLLA micro-textured coating layer had high deformation ability, where no apparent changes in the coating layer were observed even after a 5% elongation, which would be unobtainable using HA and PLLA coating layers; furthermore, this allowed the mechanically-strained Mg implant with the HA/PLLA micro-textured coating layer to preserve its excellent corrosion resistance and biocompatibility in vitro. Copyright © 2017 Elsevier B.V. All rights reserved.
Characterization and tribology of PEG-like coatings on UHMWPE for total hip replacements.
Kane, Sheryl R; Ashby, Paul D; Pruitt, Lisa A
2010-03-15
A crosslinked hydrogel coating similar to poly(ethylene glycol) (PEG) was covalently bonded to the surface of ultrahigh molecular weight polyethylene (UHMWPE) to improve the lubricity and wear resistance of the UHWMPE for use in total joint replacements. The chemistry, hydrophilicity, and protein adsorption resistance of the coatings were determined, and the wear behavior of the PEG-like coating was examined by two methods: pin-on-disk tribometry to evaluate macroscale behavior, and atomic force microscopy (AFM) to simulate asperity wear. As expected, the coating was found to be highly PEG-like, with approximately 83% ether content by x-ray photoelectron spectroscopy and more hydrophilic and resistant to protein adsorption than uncoated UHMWPE. Pin-on-disk testing showed that the PEG-like coating could survive 3 MPa of contact pressure, comparable to that experienced by total hip replacements. AFM nanoscratching experiments uncovered three damage mechanisms for the coatings: adhesion/microfracture, pure adhesion, and delamination. The latter two mechanisms appear to correlate well with wear patterns induced by pin-on-disk testing and evaluated by attenuated total reflection Fourier transform infrared spectroscopy mapping. Understanding the mechanisms by which the PEG-like coatings wear is critical for improving the behavior of subsequent generations of wear-resistant hydrogel coatings. (c) 2009 Wiley Periodicals, Inc.
Characteristics of ZrC/Ni-UDD coatings for a tungsten carbide cutting tool
NASA Astrophysics Data System (ADS)
Chayeuski, V. V.; Zhylinski, V. V.; Rudak, P. V.; Rusalsky, D. P.; Višniakov, N.; Černašėjus, O.
2018-07-01
This work deals with the features of the structure of combined ZrC/Ni-ultradisperse diamonds (UDD) coating synthesized by electroplating and cathode arc evaporation physical vapor deposition (CAE-PVD) techniques on the tungsten carbide WC - 2 wt% Co on cutting inserts to improve tool life. The microstructure, phase composition, and micro-scratch test analysis of the ZrC/Ni-UDD coating were studied. The ZrC/Ni-UDD coating consists of separate phases of zirconium carbide ZrC, α-Ni, and Ni-UDD phase. The surface morphology of the coating shows a pattern with pits, pores, and particles. Separated nanodiamond particles are present in the pores of the combined coating. Therefore, the structure of the bottom layer of Ni-UDD affects the morphology of the surface of the ZrC/Ni-UDD coating. The obtained value of the critical loads on the scratch track of the coating in 26 N proves a sufficiently high value of the adhesion strength of the intermediate Ni-UDD-layer with hard alloy of WC-Co substrate. Due to their unique structure ZrC/Ni-UDD-coatings can be used to increase the durability period of a wood-cutting milling tool for cutting chipboard by CNC machines.
USDA-ARS?s Scientific Manuscript database
The genetically engineered plum 'HoneySweet' (aka C5) has proven to be highly resistant to Plum pox virus (PPV) for over 10 years in field trials. The original vector used for transformation to develop 'HoneySweet' carried a single sense sequence of the full length PPV coat protein (ppv-cp) gene, y...
GenePattern | Informatics Technology for Cancer Research (ITCR)
GenePattern is a genomic analysis platform that provides access to hundreds of tools for the analysis and visualization of multiple data types. A web-based interface provides easy access to these tools and allows the creation of multi-step analysis pipelines that enable reproducible in silico research. A new GenePattern Notebook environment allows users to combine GenePattern analyses with text, graphics, and code to create complete reproducible research narratives.
Molecular patterns of X chromosome-linked color vision genes among 134 men of European ancestry.
Drummond-Borg, M; Deeb, S S; Motulsky, A G
1989-01-01
We used Southern blot hybridization to study X chromosome-linked color vision genes encoding the apoproteins of red and green visual pigments in 134 unselected Caucasian men. One hundred and thirteen individuals (84.3%) had a normal arrangement of their color vision pigment genes. All had one red pigment gene; the number of green pigment genes ranged from one to five with a mode of two. The frequency of molecular genotypes indicative of normal color vision (84.3%) was significantly lower than had been observed in previous studies of color vision phenotypes. Color vision defects can be due to deletions of red or green pigment genes or due to formation of hybrid genes comprising portions of both red and green pigment genes [Nathans, J., Piantanida, T.P., Eddy, R.L., Shows, T.B., Jr., & Hogness, D.S. (1986) Science 232, 203-210]. Characteristic anomalous patterns were seen in 15 (11.2%) individuals: 7 (5.2%) had patterns characteristic of deuteranomaly (mild defect in green color perception), 2 (1.5%) had patterns characteristic of deuteranopia (severe defect in green color perception), and 6 (4.5%) had protan patterns (the red perception defects protanomaly and protanopia cannot be differentiated by current molecular methods). Previously undescribed hybrid gene patterns consisting of both green and red pigment gene fragments in addition to normal red and green genes were observed in another 6 individuals (4.5%). Only 2 of these patterns were considered as deuteranomalous. Thus, DNA testing detected anomalous color vision pigment genes at a higher frequency than expected from phenotypic color vision tests. Some color vision gene arrays associated with hybrid genes are likely to mediate normal color vision. Images PMID:2915991
Transition from Spin Dewetting to continuous film in spin coating of Liquid Crystal 5CB.
Dhara, Palash; Bhandaru, Nandini; Das, Anuja; Mukherjee, Rabibrata
2018-05-08
Spin dewetting refers to spontaneous rupture of the dispensed solution layer during spin coating, resulting in isolated but periodic, regular sized domains of the solute and is pre-dominant when the solute concentration (C n ) is very low. In this article we report how the morphology of liquid crystal (LC) 5CB thin films coated on flat and patterned PMMA substrate transform from spin dewetted droplets to continuous films with increase in C n . We further show that within the spin dewetted regime, with gradual increase in the solute concentration, periodicity of the isotropic droplets (λ D ) as well as their mean diameter (d D ), gradually decreases, till the film becomes continuous at a critical concentration (C n *). Interestingly, the trend that λ D reduces with increase in C n is exact opposite to what is observed in thermal/solvent vapor induced dewetting of a thin film. The spin dewetted droplets exhibit transient Radial texture, in contrast to Schlieren texture observed in elongated threads and continuous films of 5CB, which remains in the Nematic phase at room temperature. Finally we show that by casting the film on a grating patterned substrate it becomes possible to align the spin dewetted droplets along the contours substrate patterns.
Reverse switching of surface roughness in a self-organized polydomain liquid crystal coating.
Liu, Danqing; Liu, Ling; Onck, Patrick R; Broer, Dirk J
2015-03-31
In this work we propose randomly ordered polydomain nematic liquid crystal polymer networks to reversibly generate notable jagged relief patterns at a polymer coating surface by light illumination. The domain size is controlled by the addition of traces of partly insoluble fluorinated acrylate. The photoresponse of the coating is induced by a small amount of copolymerized azobenzene monomers. Upon exposure to UV light, azobenzene undergoes trans to cis isomerization, resulting in a change in molecular order and packing within each domain. The extent of this effect and its directionality depends on the domain orientation. Localized to domain level, this morphological change forms large 3D spikes at the surface with a modulation amplitude of more than 20% of the initial thickness. The process is reversible; the surface topographical patterns erase within 10 s by stopping the light exposure. A finite element model is applied to simulate the surface topography changes of the polydomain coating. The simulations describe the formation of the topographic features in terms of light absorption and isomerization process as a function of the director orientation. The random director distribution leads to surface structures which were found to be in close agreement with the ones measured by interference microscopy. The effect of domain size on surface roughness and depth modulation was explored and related to the internal mechanical constraints. The use of nematic liquid crystal polydomains confined in a polymer network largely simplifies the fabrication of smart coatings with a prominent triggered topographic response.
Dual Imprinted Polymer Thin Films via Pattern Directed Self-Organization.
Grolman, Danielle; Bandyopadhyay, Diya; Al-Enizi, Abdullah; Elzatahry, Ahmed; Karim, Alamgir
2017-06-21
Synthetic topographically patterned films and coatings are typically contoured on one side, yet many of nature's surfaces have distinct textures on different surfaces of the same object. Common examples are the top and bottom sides of the butterfly wing or lotus leaf, onion shells, and the inside versus outside of the stem of a flower. Inspired by nature, we create dual (top and bottom) channel patterned polymer films. To this end, we first develop a novel fabrication method to create ceramic line channel relief structures by converting the oligomeric residue of stamped poly(dimethylsiloxane) (PDMS) nanopatterns on silicon substrates to glass (SiOx, silica) by ultraviolet-ozone (UVO) exposure. These silica patterned substrates are flow coated with polystyrene (PS) films and confined within an identically patterned top confining soft PDMS elastomer film. Annealing of the sandwich structures drives the PS to rapidly mold fill the top PDMS pattern in conjunction with a dewetting tendency of the PS on the silica pattern. Varying the film thickness h, from less than to greater than the pattern height, and varying the relative angle between the top-down and bottom-up patterned confinement surfaces create interesting uniform and nonuniform digitized defects in PS channel patterns, as also a defect-free channel regime. Our dual patterned polymer channels provide a novel fabrication route to topographically imprinted Moiré patterns (whose applications range from security encrypting holograms to sensitive strain gauges), and their basic laser light diffractions properties are illustrated and compared to graphical simulations and 2D-FFT of real-space AFM channel patterns. While traditional "geometrical" and "fringe" Moiré patterns function by superposition of two misaligned optical patterned transmittance gratings, our topographic pattern gratings are quite distinct and may allow for more unique holographic optical characteristics with further development.
Construction and DNA condensation of cyclodextrin-coated gold nanoparticles with anthryl grafts.
Zhao, Di; Chen, Yong; Liu, Yu
2014-07-01
The condensation of DNA in a controlled manner is one of the key steps in gene delivery and gene therapy. For this purpose, a water-soluble supramolecular nanostructure is constructed by coating 14 β-cyclodextrins onto the surface of a gold nanoparticle, followed by the noncovalent association of different amounts of anthryl-modified adamantanes with coated β-cyclodextrins. The strong binding of β-cyclodextrins with anthryl adamantanes (K(S) =8.61×10(4) M(-1)) efficiently stabilizes the supramolecular nanostructure. Spectrophotometric fluorescence spectra and microscopic studies demonstrated that, with many anthryl grafts that can intercalate in the outer space of the DNA double helix, this supramolecular nanostructure showed good condensation abilities to calf thymus DNA. Significantly, the condensation efficiency of supramolecular nanostructure towards DNA could be conveniently controlled by adjusting the ratio between gold nanoparticles and anthryl adamantane grafts, leading to the formation of DNA condensates of a size that are suitable for the endocytosis of hepatoma cells, which will make it potentially applicable in many fields of medicinal science and biotechnology. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Wada, A; Kunieda, T; Nishimura, M; Kakizoe-Ishida, Y; Watanabe, N; Ohkawa, K; Tsudzuki, M
2005-01-01
"Tawny" is an autosomal recessive coat color mutation found in a wild population of Mus musculus molossinus. The inbred strain MSKR carries the mutation. The causative gene Mc1r(taw) of the tawny phenotype is the second recessive allele at the melanocortin 1 receptor locus and is dominant to the first recessive allele, "recessive yellow" (Mc1r(e)). The Mc1r(taw) gene has six nucleotide substitutions, and its forecasted transcript has three amino acid substitutions (i.e., V101A, V216A, W252C). Though the nucleotide substitutions leading to V101A and V216A exist in various mouse strains, the nucleotide substitution leading to W252C exists in only tawny-colored mice. Thus this substitution is considered to be responsible for the expression of the tawny coat color. The frequency of the allele having this nucleotide substitution was 9.21% in the wild M. m. molossinus population inhabiting Sakai City, Osaka Prefecture, Japan, where the ancestral mice of the MSKR strain were captured.
NASA Astrophysics Data System (ADS)
Li, Junbo; Wu, Wenlan; Gao, Jiayu; Liang, Ju; Zhou, Huiyun; Liang, Lijuan
2017-03-01
Synthesized vectors with nanoscale size and stable colloid dispersion are highly desirable for improving gene delivery efficiency. Here, a core-shell template particle was constructed with polyethylene glycol- b-poly1-(3-aminopropyl)-3-(2-methacryloyloxy propylimidazolium bromine) (PEG- b-PAMPImB) coating gold nanoparticles (PEG- b-PAMPImB-@-Au NPs) for loading DNA and delivering in vitro. Data from transmission electron microscopy (TEM) and dynamic light scattering (DLS) suggest that these nanoplexes, by forming an electrostatic complex with DNA at the inner PAMPImB shell, offer steric protection for the outer PEG corona leading to single dispersion and small size. Notably, higher colloid stability and lower cytotoxicity were achieved with these nanoplexes when compared with PAMPImB monolayer-coated gold nanoparticles (Au NPs). Confocal laser scanning microscopy and intracellular trafficking TEM further indicate that the nanoplexes can translocate across the cell membrane and partly enter the nucleus for high efficient expression. Thus, template assembly represents a promising approach to control the size and colloid stability of gene vectors and ensure safety and efficiency of DNA delivery.
How to adjust desired drug release patterns from ethylcellulose-coated dosage forms.
Siepmann, F; Hoffmann, A; Leclercq, B; Carlin, B; Siepmann, J
2007-06-04
The aim of this study was to provide an easy and efficient tool to adjust desired drug release kinetics from (aqueous) ethylcellulose-coated solid dosage forms and to better understand the underlying mass transport mechanisms. Pure ethylcellulose films are poorly permeable for many substances and can result in very low release rates for certain drugs from coated dosage forms, if the film coatings are completely formed and remain intact upon exposure to the release media. To increase the permeability of the polymeric membranes, different amounts of a water-soluble poly(vinyl alcohol)-poly(ethylene glycol) graft copolymer (PVA-PEG graft copolymer) were added to an aqueous ethylcellulose dispersion (Aquacoat ECD). Importantly, the presence of only a low percentage of this hydrophilic copolymer significantly increased the resulting water uptake rate and extent, dry weight loss and drug permeability of the films. In contrast to hydroxypropyl methylcellulose (HPMC), the PVA-PEG graft copolymer does not cause flocculation of the colloidal coating dispersion (leading to potentially variable release rates). Interestingly, the transport of water as well as of the model drug theophylline through the polymeric networks was primarily controlled by pure diffusion. The penetration kinetics could be quantitatively described by Fick's law of diffusion, irrespective of the type of release medium and PVA-PEG graft copolymer content. Most important from a practical point of view, a broad spectrum of pH-independent drug release rates can easily be obtained from drug-loaded pellets by simply varying the PVA-PEG graft copolymer content. An appropriate curing step after coating is required, but interestingly the investigated curing conditions (differing in time and relative humidity) resulted in very similar drug release patterns, indicating that stable film structures are likely to be achieved.
NASA Astrophysics Data System (ADS)
Zhou, Yuping; Zhang, Qi
2018-04-01
In the information environment, digital and information processing to Li brocade patterns reveals an important means of Li ethnic style and inheriting the national culture. Adobe Illustrator CS3 and Java language were used in the paper to make "variation" processing to Li brocade patterns, and generate "Li brocade pattern mutant genes". The generation of pattern mutant genes includes color mutation, shape mutation, adding and missing transform, and twisted transform, etc. Research shows that Li brocade pattern mutant genes can be generated by using the Adobe Illustrator CS3 and the image processing tools of Java language edit, etc.
Liu, Liang; Ma, Siyuan; Pei, Yunheng; Xiong, Xiao; Sivakumar, Preeth; Singler, Timothy J
2016-08-24
We report a method to achieve highly uniform inkjet-printed silver nitrate (AgNO3) and a reactive silver precursor patterns on rigid and flexible substrates functionalized with polydopamine (PDA) coatings. The printed AgNO3 patterns on PDA-coated substrates (glass and polyethylene terephthalate (PET)) exhibit a narrow thickness distribution ranging between 0.9 and 1 μm in the line transverse direction and uniform deposition profiles in the line axial direction. The deposited reactive silver precursor patterns on PDA-functionalized substrates also show "dome-shaped" morphology without "edge-thickened" structure due to "coffee-stain" effect. We posit that the highly uniform functional ink deposits formed on PDA-coated substrates are attributable to the strong binding interaction between the abundant catecholamine moieties at the PDA surface and the metallic silver cations (Ag(+) or Ag(NH3)(2+)) in the solutal inks. During printing of the ink rivulet and solvent evaporation, the substrate-liquid ink (S-L) interface is enriched with the silver-based cations and a solidification at the S/L interface is induced. The preferential solidification initiated at the S-L interface is further verified by the in situ visualization of the dynamic solidification process during solvent evaporation, and results suggest an enhanced crystal nucleation and growth localized at the S-L interface on PDA functionalized substrates. This interfacial interaction mediates solute transport in the liquid phase, resulting in the controlled enrichment of solute at the S-L interface and mitigated solute precipitation in both the contact line region and the liquid ink-vapor (L-V) interface due to evaporation. This mediated transport contributes to the final uniform solid deposition for both types of ink systems. This technique provides a complementary strategy for achieving highly uniform inkjet-printed crystalline structures, and can serve as an innovative foundation for high-precision additive delivery of functional materials.
USDA-ARS?s Scientific Manuscript database
The complete nucleotide sequence of a recently discovered Florida (FL) isolate of Hibiscus infecting Cilevirus (HiCV) was determined by Sanger sequencing. The movement- and coat- protein gene sequences of the HiCV-FL isolate are more divergent than other genes of the previously sequenced HiCV-HA (Ha...
Evaluation of promoters and visual markers for transformation of eastern white pine
Allan Zipf; Alex M. Diner; Rufina Ward; Suman Bharara; George Brown; R. Nagmani; L.K. Pareek; Govind C. Sharma
2001-01-01
This report serves to evaluate possible promoters for use in the production of trmsgenic eastern white pine (Pinus strobus L.). Embryogenic cultures of eastern white pine were bombarded with gold particles coated separately with a variety of gene constructs containing the Uida B-glucoronidase (GUS) or green flourescent protein (GFP) reporter gene....
Cathodic Polarization Coats Titanium Based Implant Materials with Enamel Matrix Derivate (EMD)
Frank, Matthias J.; Walter, Martin S.; Rubert, Marina; Thiede, Bernd; Monjo, Marta; Reseland, Janne E.; Haugen, Håvard J.; Lyngstadaas, Ståle Petter
2014-01-01
The idea of a bioactive surface coating that enhances bone healing and bone growth is a strong focus of on-going research for bone implant materials. Enamel matrix derivate (EMD) is well documented to support bone regeneration and activates growth of mesenchymal tissues. Thus, it is a prime candidate for coating of existing implant surfaces. The aim of this study was to show that cathodic polarization can be used for coating commercially available implant surfaces with an immobilized but functional and bio-available surface layer of EMD. After coating, XPS revealed EMD-related bindings on the surface while SIMS showed incorporation of EMD into the surface. The hydride layer of the original surface could be activated for coating in an integrated one-step process that did not require any pre-treatment of the surface. SEM images showed nano-spheres and nano-rods on coated surfaces that were EMD-related. Moreover, the surface roughness remained unchanged after coating, as it was shown by optical profilometry. The mass peaks observed in the matrix-assisted laser desorption/ionization time-of-flight mass spectroscopy (MALDI-TOF MS) analysis confirmed the integrity of EMD after coating. Assessment of the bioavailability suggested that the modified surfaces were active for osteoblast like MC3M3-E1 cells in showing enhanced Coll-1 gene expression and ALP activity. PMID:28788564
NASA Astrophysics Data System (ADS)
Park, Hyungmin; Kim, Jae-Up; Park, Soojin
2012-02-01
A simple, straightforward process for fabricating multi-scale micro- and nanostructured patterns from polystyrene-block-poly(2-vinylpyridine) (PS-b-P2VP)/poly(methyl methacrylate) (PMMA) homopolymer in a preferential solvent for PS and PMMA is demonstrated. When the PS-b-P2VP/PMMA blend films were spin-coated onto a silicon wafer, PS-b-P2VP micellar arrays consisting of a PS corona and a P2VP core were formed, while the PMMA macrodomains were isolated, due to the macrophase separation caused by the incompatibility between block copolymer micelles and PMMA homopolymer during the spin-coating process. With an increase of PMMA composition, the size of PMMA macrodomains increased. Moreover, the P2VP blocks have a strong interaction with a native oxide of the surface of the silicon wafer, so that the P2VP wetting layer was first formed during spin-coating, and PS nanoclusters were observed on the PMMA macrodomains beneath. Whereas when a silicon surface was modified with a PS brush layer, the PS nanoclusters underlying PMMA domains were not formed. The multi-scale patterns prepared from copolymer micelle/homopolymer blend films are used as templates for the fabrication of gold nanoparticle arrays by incorporating the gold precursor into the P2VP chains. The combination of nanostructures prepared from block copolymer micellar arrays and macrostructures induced by incompatibility between the copolymer and the homopolymer leads to the formation of complex, multi-scale surface patterns by a simple casting process.A simple, straightforward process for fabricating multi-scale micro- and nanostructured patterns from polystyrene-block-poly(2-vinylpyridine) (PS-b-P2VP)/poly(methyl methacrylate) (PMMA) homopolymer in a preferential solvent for PS and PMMA is demonstrated. When the PS-b-P2VP/PMMA blend films were spin-coated onto a silicon wafer, PS-b-P2VP micellar arrays consisting of a PS corona and a P2VP core were formed, while the PMMA macrodomains were isolated, due to the macrophase separation caused by the incompatibility between block copolymer micelles and PMMA homopolymer during the spin-coating process. With an increase of PMMA composition, the size of PMMA macrodomains increased. Moreover, the P2VP blocks have a strong interaction with a native oxide of the surface of the silicon wafer, so that the P2VP wetting layer was first formed during spin-coating, and PS nanoclusters were observed on the PMMA macrodomains beneath. Whereas when a silicon surface was modified with a PS brush layer, the PS nanoclusters underlying PMMA domains were not formed. The multi-scale patterns prepared from copolymer micelle/homopolymer blend films are used as templates for the fabrication of gold nanoparticle arrays by incorporating the gold precursor into the P2VP chains. The combination of nanostructures prepared from block copolymer micellar arrays and macrostructures induced by incompatibility between the copolymer and the homopolymer leads to the formation of complex, multi-scale surface patterns by a simple casting process. Electronic supplementary information (ESI) available: AFM images of PS-b-P2VP/PMMA blend films and cross-sectional line scans. See DOI: 10.1039/c2nr11792d
Galperin, Michael Y; Mekhedov, Sergei L; Puigbo, Pere; Smirnov, Sergey; Wolf, Yuri I; Rigden, Daniel J
2012-01-01
Three classes of low-G+C Gram-positive bacteria (Firmicutes), Bacilli, Clostridia and Negativicutes, include numerous members that are capable of producing heat-resistant endospores. Spore-forming firmicutes include many environmentally important organisms, such as insect pathogens and cellulose-degrading industrial strains, as well as human pathogens responsible for such diseases as anthrax, botulism, gas gangrene and tetanus. In the best-studied model organism Bacillus subtilis, sporulation involves over 500 genes, many of which are conserved among other bacilli and clostridia. This work aimed to define the genomic requirements for sporulation through an analysis of the presence of sporulation genes in various firmicutes, including those with smaller genomes than B. subtilis. Cultivable spore-formers were found to have genomes larger than 2300 kb and encompass over 2150 protein-coding genes of which 60 are orthologues of genes that are apparently essential for sporulation in B. subtilis. Clostridial spore-formers lack, among others, spoIIB, sda, spoVID and safA genes and have non-orthologous displacements of spoIIQ and spoIVFA, suggesting substantial differences between bacilli and clostridia in the engulfment and spore coat formation steps. Many B. subtilis sporulation genes, particularly those encoding small acid-soluble spore proteins and spore coat proteins, were found only in the family Bacillaceae, or even in a subset of Bacillus spp. Phylogenetic profiles of sporulation genes, compiled in this work, confirm the presence of a common sporulation gene core, but also illuminate the diversity of the sporulation processes within various lineages. These profiles should help further experimental studies of uncharacterized widespread sporulation genes, which would ultimately allow delineation of the minimal set(s) of sporulation-specific genes in Bacilli and Clostridia. PMID:22882546
Sound Waves Levitate Substrates
NASA Technical Reports Server (NTRS)
Lee, M. C.; Wang, T. G.
1982-01-01
System recently tested uses acoustic waves to levitate liquid drops, millimeter-sized glass microballoons, and other objects for coating by vapor deposition or capillary attraction. Cylindrical contactless coating/handling facility employs a cylindrical acoustic focusing radiator and a tapered reflector to generate a specially-shaped standing wave pattern. Article to be processed is captured by the acoustic force field under the reflector and moves as reflector is moved to different work stations.
Structured Antireflective Coating for Silicon at Submillimeter Frequencies
NASA Astrophysics Data System (ADS)
Padilla, Estefania
2018-01-01
Observations at millimeter and submillimeter wavelengths are useful for many astronomical studies, such as the polarization of the cosmic microwave background or the formation and evolution of galaxy clusters. In order to allow observations over a broad spectral bandwidth (approximatively from 70 to 420 GHz), innovative broadband anti-reflective (AR) optics must be utilized in submillimeter telescopes. Due to its low loss and high refractive index, silicon is a fine optical material at these frequencies, but an AR coating with multiple layers is required to maximize its transmission over a wide bandwidth. Structured multilayer AR coatings for silicon are currently being developed at Caltech and JPL. The development process includes the design of the structured layers with commercial electromagnetic simulation software, the fabrication by using deep reactive ion etching, and the test of the transmission and reflection of the patterned wafers. Geometrical 3D patterns have successfully been etched at the surface of the silicon wafers creating up to 2 layers with different effective refractive indices. The transmission and reflection of single AR layer wafers, measured between 75 and 330 GHz, are close to the simulation predictions. These results allow the development of new designs with 5 or 6 AR layers in order to improve the bandwidth and transmission of the silicon AR coatings.
Stankowich, Theodore; Coss, Richard G
2006-01-01
When a previously common predator disappears owing to local extinction, the strong source of natural selection on prey to visually recognize that predator becomes relaxed. At present, we do not know the extent to which recognition of a specific predator is generalized to similar looking predators or how a specific predator-recognition cue, such as coat pattern, degrades under prolonged relaxed selection. Using predator models, we show that deer exhibit a more rapid and stronger antipredator response to their current predator, the puma, than to a leopard displaying primitive rosettes similar to a locally extinct predator, an early jaguar. Presentation of a novel tiger with a striped coat engendered an intermediate speed of predator recognition and strength of antipredator behaviour. Responses to the leopard model slightly exceeded responses to a non-threatening deer model, suggesting that thousands of years of relaxed selection have led to the loss of recognition of the spotted coat as a jaguar-recognition cue, and that the spotted coat has regained its ability to camouflage the felid form. Our results shed light on the evolutionary arms race between adoption of camouflage to facilitate hunting and the ability of prey to quickly recognize predators by their formerly camouflaging patterns. PMID:17148247
Environmentally stable perovskite film for active material of high stability solid state solar cells
NASA Astrophysics Data System (ADS)
Bahtiar, A.; Putri, M.; Nurazizah, E. S.; Risdiana; Furukawa, Y.
2018-05-01
We studied new perovskite material lead (II) thiocyanate [Pb(SCN)2] in ambient air with humidity above 90%. We prepared perovskite film by use of two-step method combination of spin-coating and dip-coating technique. The Pb(SCN)2 film was first spin-coated either on bare glass or TiO2 coated glass and then followed by dipping it into methylammonium iodide (MAI) solution. The UV-Vis spectrum of Pb(SCN)2 film shows absorption at wavelength shorter than 400 nm. Meanwhile, perovskite MAPb(SCN)xI3-x film absorps light ranging from 300 nm to 760 nm, which shows that the perovskite film can absorp more light to be converted into free charge carrier for generating electricity in solar cells. The XRD patterns shows that perovskite peaks are clearly observed which confirms that perovskite is already well formed. We also observe no significant changes in XRD pattern of perovskite films after stored for five days at ambient air with humidity exceed 90%. This result shows that perovskite MAPb(SCN)XI3-X film is environmentally stable, therefore high stability perovskite solar cells is expected to be produced in ambient air with high humidity. This is in accordance with the SEM images of surface morphology that shows no “pin-hole”.
NASA Astrophysics Data System (ADS)
Esmeryan, Karekin D.; Castano, Carlos E.; Mohammadi, Reza; Lazarov, Yuliyan; Radeva, Ekaterina I.
2018-02-01
Condensation frosting is an undesired natural phenomenon that could be impeded efficiently using appropriate wettability and morphologically patterned surfaces. The icephobic properties of carbon soot and the fabrication scalability of its synthesis method are a good foundation for anti-frosting applications; however, the fundamentals of frost growth and spreading on sooted surfaces have not been examined yet. In this study, we investigate the anti-frosting performance of three groups of superhydrophobic soot coatings by means of 16 MHz quartz crystal microbalances (QCMs). The analysis of the real-time sensor signal of each soot coated QCM pattern shows that frost formation and its propagation velocity depend on the quantity of oxygen functionalities and structural defects in the material. In turn, the reduction of both parameters shifts the onset of frost growth to temperatures below -20 °C, whereas the interdroplet ice bridging is slowed by a factor of four. Moreover, high-resolution scanning electron micrographs of the samples imply delamination upon defrosting of the soot with spherical-like morphology via polar interactions driven mechanism. These results reveal an opportunity for control of frost incipiency on sooted surfaces by adjusting the synthesis conditions and depositing soot coatings with as low as possible content of hydrophilic active sites.
Runkel, F; Marquardt, A; Stoeger, C; Kochmann, E; Simon, D; Kohnke, B; Korthaus, D; Wattler, F; Fuchs, H; Hrabé de Angelis, M; Stumm, G; Nehls, M; Wattler, S; Franz, T; Augustin, M
2004-11-01
Reduced Coat 2 (Rco2) is an ENU-induced mutation affecting hair follicle morphogenesis by an abnormal and protracted catagen. We describe chromosomal mapping and molecular identification of the autosomal dominant Rco2 mutation. The Rco2 critical region on mouse chromosome 11 encompasses the alopecia loci, Bareskin (Bsk), Rex-denuded (Re(den)), Recombination induced mutation 3 (Rim3), and Defolliculated (Dfl). Recently, the gasdermin (Gsdm) gene was described as predominantly expressed in skin and gastric tissues. We provide evidence for a murine-specific gene cluster consisting of Gsdm and two closely related genes which we designate as Gsdm2 and Gsdm3. We show that Gsdm3 reflects a mutation hotspot and that Gsdm3 mutations cause alopecia in Rco2, Re(den), and Bsk mice. We infer a role of Gsdm3 during the catagen to telogen transition at the end of hair follicle morphogenesis and the formation of hair follicle-associated sebaceous glands.
Paris, Daniel H; Blacksell, Stuart D; Newton, Paul N; Day, Nicholas P J
2008-12-01
We present a loop-mediated isothermal PCR assay (LAMP) targeting the groEL gene, which encodes the 60kDa heat shock protein of Orientia tsutsugamushi. Evaluation included testing of 63 samples of contemporary in vitro isolates, buffy coats and whole blood samples from patients with fever. Detection limits for LAMP were assessed by serial dilutions and quantitation by real-time PCR assay based on the same target gene: three copies/microl for linearized plasmids, 26 copies/microl for VERO cell culture isolates, 14 copies/microl for full blood samples and 41 copies/microl for clinical buffy coats. Based on a limited sample number, the LAMP assay is comparable in sensitivity with conventional nested PCR (56kDa gene), with limits of detection well below the range of known admission bacterial loads of patients with scrub typhus. This inexpensive method requires no sophisticated equipment or sample preparation, and may prove useful as a diagnostic assay in financially poor settings; however, it requires further prospective validation in the field setting.
Evidence of a major gene influencing hair length and heat tolerance in Bos taurus cattle.
Olson, T A; Lucena, C; Chase, C C; Hammond, A C
2003-01-01
Evidence was found that supports the existence of a major gene (designated as the slick hair gene), dominant in mode of inheritance, that is responsible for producing a very short, sleek hair coat. Cattle with slick hair were observed to maintain lower rectal temperatures (RT). The gene is found in Senepol cattle and criollo (Spanish origin) breeds in Central and South America. This gene is also found in a Venezuelan composite breed, the Carora, formed from the Brown Swiss and a Venezuelan criollo breed. Two sets of backcross matings of normal-haired sire breeds to Senepol crossbred dams assumed to be heterozygous for the slick hair gene resulted in ratios of slick to normal-haired progeny that did not significantly differ from 1:1. Data from Carora x Holstein crossbred cows in Venezuela also support the concept of a major gene that is responsible for the slick hair coat of the Carora breed. Cows that were 75% Holstein: 25% Carora in breed composition segregated with a ratio that did not differ from 1:1, as would be expected from a backcross matinginvolving a dominant gene. The effect of the slick hair gene on RT depended on the degree of heat stress and appeared to be affected by age and/or lactation status. The decreased RT observed for slick-haired crossbred calves compared to normal-haired contemporaries ranged from 0.18 to 0.4 degrees C. An even larger decrease in RT (0.61 degrees C; P < 0.01) was observed in lactating Carora x Holstein F1 crossbred cows, even though it did not appear that these cows were under severe heat stress. The improved thermotolerance of crossbred calves due to their slick hair coats did not result in increased weaning weights, possibly because both the slick and normal-haired calves were being nursed by slick-haired dams. There were indications that the slick-haired calves grew faster immediately following weaning and that their growth during the cooler months of the year was not compromised significantly by their reduced quantity of hair. In the Carora x Holstein crossbred cows there was a positive effect of slick hair on milk yield under dry, tropical conditions.
The inheritance of fingerprint patterns.
Slatis, H M; Katznelson, M B; Bonné-Tamir, B
1976-05-01
Analysis of the fingerprints of 571 members of the Habbanite isolate suggest inherited patterns and pattern sequences. A genetic theory has been developed; it assumes that the basic fingerprint pattern sequence is all ulnar loops and that a variety of genes cause deviations from this pattern sequence. Genes that have been proposed include: (1) a semidominant gene for whorls on the thumbs (one homozygote has whorls on both thumbs, the other has ulnar loops on both thumbs and the heterozygote usually has two ulnar loops or one ulnar loop and one whorl); (2) a semidominant gene for whorls on the ring fingers which acts like the gene for whorls on the thumbs; (3) a dominant gene for arches on the thumbs and often on other fingers; (4) one or more dominant genes for arches on the fingers; (5) a dominant gene for whorls on all fingers except for an ulnar loop on the middle finger; (6) a dominant gene for radial loops on the index fingers, frequently associated with an arch on the middle fingers; and (7) a recessive gene for radial loops on the ring and little fingers. These genes may act independently or may show epistasis.
The inheritance of fingerprint patterns.
Slatis, H M; Katznelson, M B; Bonné-Tamir, B
1976-01-01
Analysis of the fingerprints of 571 members of the Habbanite isolate suggest inherited patterns and pattern sequences. A genetic theory has been developed; it assumes that the basic fingerprint pattern sequence is all ulnar loops and that a variety of genes cause deviations from this pattern sequence. Genes that have been proposed include: (1) a semidominant gene for whorls on the thumbs (one homozygote has whorls on both thumbs, the other has ulnar loops on both thumbs and the heterozygote usually has two ulnar loops or one ulnar loop and one whorl); (2) a semidominant gene for whorls on the ring fingers which acts like the gene for whorls on the thumbs; (3) a dominant gene for arches on the thumbs and often on other fingers; (4) one or more dominant genes for arches on the fingers; (5) a dominant gene for whorls on all fingers except for an ulnar loop on the middle finger; (6) a dominant gene for radial loops on the index fingers, frequently associated with an arch on the middle fingers; and (7) a recessive gene for radial loops on the ring and little fingers. These genes may act independently or may show epistasis. PMID:1266855
Multi-walled carbon/IF-WS2 nanoparticles with improved thermal properties
NASA Astrophysics Data System (ADS)
Xu, Fang; Almeida, Trevor P.; Chang, Hong; Xia, Yongde; Wears, M. Lesley; Zhu, Yanqiu
2013-10-01
A unique new class of core-shell structured composite nanoparticles, C-coated inorganic fullerene-like WS2 (IF-WS2) hollow nanoparticles, has been created for the first time in large quantities, by a continuous chemical vapour deposition method using a rotary furnace. Transmission electron microscopy and Raman characterisations of the resulting samples reveal that the composite nanoparticles exhibited a uniform shell of carbon coating, ranging from 2-5 nm on the IF-WS2 core, with little or no agglomeration. Importantly, thermogravimetric analysis and differential scanning calorimetry analysis confirm that their thermal stability against oxidation in air has been improved by about 70 °C, compared to the pristine IF-WS2, making these new C-coated IF-WS2 nanoparticles more attractive for critical engineering applications.A unique new class of core-shell structured composite nanoparticles, C-coated inorganic fullerene-like WS2 (IF-WS2) hollow nanoparticles, has been created for the first time in large quantities, by a continuous chemical vapour deposition method using a rotary furnace. Transmission electron microscopy and Raman characterisations of the resulting samples reveal that the composite nanoparticles exhibited a uniform shell of carbon coating, ranging from 2-5 nm on the IF-WS2 core, with little or no agglomeration. Importantly, thermogravimetric analysis and differential scanning calorimetry analysis confirm that their thermal stability against oxidation in air has been improved by about 70 °C, compared to the pristine IF-WS2, making these new C-coated IF-WS2 nanoparticles more attractive for critical engineering applications. Electronic supplementary information (ESI) available: Sketch of the rotary furnace, XRD pattern comparison of IF-WS2 and 2H WS2, XRD patterns of C-coated IF-WS2 (41-50°), and TGA and MS curves for pristine IF-WS2. See DOI: 10.1039/c3nr03844k
Architecture and assembly of the Bacillus subtilis spore coat.
Plomp, Marco; Carroll, Alicia Monroe; Setlow, Peter; Malkin, Alexander J
2014-01-01
Bacillus spores are encased in a multilayer, proteinaceous self-assembled coat structure that assists in protecting the bacterial genome from stresses and consists of at least 70 proteins. The elucidation of Bacillus spore coat assembly, architecture, and function is critical to determining mechanisms of spore pathogenesis, environmental resistance, immune response, and physicochemical properties. Recently, genetic, biochemical and microscopy methods have provided new insight into spore coat architecture, assembly, structure and function. However, detailed spore coat architecture and assembly, comprehensive understanding of the proteomic composition of coat layers, and specific roles of coat proteins in coat assembly and their precise localization within the coat remain in question. In this study, atomic force microscopy was used to probe the coat structure of Bacillus subtilis wild type and cotA, cotB, safA, cotH, cotO, cotE, gerE, and cotE gerE spores. This approach provided high-resolution visualization of the various spore coat structures, new insight into the function of specific coat proteins, and enabled the development of a detailed model of spore coat architecture. This model is consistent with a recently reported four-layer coat assembly and further adds several coat layers not reported previously. The coat is organized starting from the outside into an outermost amorphous (crust) layer, a rodlet layer, a honeycomb layer, a fibrous layer, a layer of "nanodot" particles, a multilayer assembly, and finally the undercoat/basement layer. We propose that the assembly of the previously unreported fibrous layer, which we link to the darkly stained outer coat seen by electron microscopy, and the nanodot layer are cotH- and cotE- dependent and cotE-specific respectively. We further propose that the inner coat multilayer structure is crystalline with its apparent two-dimensional (2D) nuclei being the first example of a non-mineral 2D nucleation crystallization pattern in a biological organism.
Architecture and Assembly of the Bacillus subtilis Spore Coat
Plomp, Marco; Carroll, Alicia Monroe; Setlow, Peter; Malkin, Alexander J.
2014-01-01
Bacillus spores are encased in a multilayer, proteinaceous self-assembled coat structure that assists in protecting the bacterial genome from stresses and consists of at least 70 proteins. The elucidation of Bacillus spore coat assembly, architecture, and function is critical to determining mechanisms of spore pathogenesis, environmental resistance, immune response, and physicochemical properties. Recently, genetic, biochemical and microscopy methods have provided new insight into spore coat architecture, assembly, structure and function. However, detailed spore coat architecture and assembly, comprehensive understanding of the proteomic composition of coat layers, and specific roles of coat proteins in coat assembly and their precise localization within the coat remain in question. In this study, atomic force microscopy was used to probe the coat structure of Bacillus subtilis wild type and cotA, cotB, safA, cotH, cotO, cotE, gerE, and cotE gerE spores. This approach provided high-resolution visualization of the various spore coat structures, new insight into the function of specific coat proteins, and enabled the development of a detailed model of spore coat architecture. This model is consistent with a recently reported four-layer coat assembly and further adds several coat layers not reported previously. The coat is organized starting from the outside into an outermost amorphous (crust) layer, a rodlet layer, a honeycomb layer, a fibrous layer, a layer of “nanodot” particles, a multilayer assembly, and finally the undercoat/basement layer. We propose that the assembly of the previously unreported fibrous layer, which we link to the darkly stained outer coat seen by electron microscopy, and the nanodot layer are cotH- and cotE- dependent and cotE-specific respectively. We further propose that the inner coat multilayer structure is crystalline with its apparent two-dimensional (2D) nuclei being the first example of a non-mineral 2D nucleation crystallization pattern in a biological organism. PMID:25259857
Ferguson, Laura C; Maroja, Luana; Jiggins, Chris D
2011-12-01
The evolution of pigmentation in vertebrates and flies has involved repeated divergence at a small number of genes related to melanin synthesis. Here, we study insect melanin synthesis genes in Heliconius butterflies, a group characterised by its diversity of wing patterns consisting of black (melanin), and yellow and red (ommochrome) pigmented scales. Consistent with their respective biochemical roles in Drosophila melanogaster, ebony is upregulated in non-melanic wing regions destined to be pigmented red whilst tan is upregulated in melanic regions. Wing regions destined to be pigmented yellow, however, are downregulated for both genes. This pattern is conserved across multiple divergent and convergent phenotypes within the Heliconii, suggesting a conserved mechanism for the development of black, red and yellow pattern elements across the genus. Linkage mapping of five melanin biosynthesis genes showed that, in contrast to other organisms, these genes do not control pattern polymorphism. Thus, the pigmentation genes themselves are not the locus of evolutionary change but lie downstream of a wing pattern regulatory factor. The results suggest a modular system in which particular combinations of genes are switched on whenever red, yellow or black pattern elements are favoured by natural selection for diverse and mimetic wing patterns. © Springer-Verlag 2011
Laser-induced erasable patterns in a N* liquid crystal on an iron doped lithium niobate surface.
Habibpourmoghadam, Atefeh; Lucchetti, Liana; Evans, Dean R; Reshetnyak, Victor Y; Omairat, Faissal; Schafforz, Samuel L; Lorenz, Alexander
2017-10-16
A chiral nematic (N*) liquid crystal (LC) was hybridized with a z-cut iron doped lithium niobate (Fe:LN) substrate and exposed with a focused continuous wave diode laser beam. The N* LC layer was confined with a cover glass to provide a homogeneous LC layer thickness. Two distinct kinds of test cells were investigated, one with an uncoated glass covering slip and one with an indium tin oxide (ITO) coated cover glass. Photo generated electric fields (generated in the Fe:LN) resulted in a localized defect formation and textural transitions in the N* LC. Due to field confinement, the field induced responses were more localized in samples with ITO coated cover glasses. By scanning the laser beam on programmed trajectories, formation of persistent patterns could be achieved in the N* LC layer. Polarized optical microscopy of the exposed samples revealed that these patterns consisted of adjacent circular Frank-Pryce defects. Exposure with a slightly defocused laser beam could be applied selectively to erase these patterns. Thus, a promising method is reported to generate reconfigurable patterns, photonic motives, and touch sensitive devices in a hybridized N* LC with micron accuracy.
Lu, Yuan; Reyes, Jose; Walter, Sean; Gonzalez, Trevor; Medrano, Geraldo; Boswell, Mikki; Boswell, William; Savage, Markita; Walter, Ronald
2018-06-01
Evolutionarily conserved diurnal circadian mechanisms maintain oscillating patterns of gene expression based on the day-night cycle. Xiphophorus fish have been used to evaluate transcriptional responses after exposure to various light sources and it was determined that each source incites distinct genetic responses in skin tissue. However, basal expression levels of genes that show oscillating expression patterns in day-night cycle, may affect the outcomes of such experiments, since basal gene expression levels at each point in the circadian path may influence the profile of identified light responsive genes. Lack of knowledge regarding diurnal fluctuations in basal gene expression patterns may confound the understanding of genetic responses to external stimuli (e.g., light) since the dynamic nature of gene expression implies animals subjected to stimuli at different times may be at very different stages within the continuum of genetic homeostasis. We assessed basal gene expression changes over a 24-hour period in 200 select Xiphophorus gene targets known to transcriptionally respond to various types of light exposure. We identified 22 genes in skin, 36 genes in brain and 28 genes in liver that exhibit basal oscillation of expression patterns. These genes, including known circadian regulators, produced the expected expression patterns over a 24-hour cycle when compared to circadian regulatory genes identified in other species, especially human and other vertebrate animal models. Our results suggest the regulatory network governing diurnal oscillating gene expression is similar between Xiphophorus and other vertebrates for the three Xiphophorus organs tested. In addition, we were able to categorize light responsive gene sets in Xiphophorus that do, and do not, exhibit circadian based oscillating expression patterns. Copyright © 2017 Elsevier Inc. All rights reserved.
PLGA/polymeric liposome for targeted drug and gene co-delivery.
Wang, Hanjie; Zhao, Peiqi; Su, Wenya; Wang, Sheng; Liao, Zhenyu; Niu, Ruifang; Chang, Jin
2010-11-01
Chemotherapy is one of the most effective approaches to treat cancers in the clinic, but the problems, such as multidrug resistance (MDR), low bioavailability and toxicity, severely constrain the further application of chemotherapy. Our group recently reported that cationic PLGA/folate coated PEGlated polymeric liposome core-shell nanoparticles (PLGA/FPL NPs). It was self-assembled from a hydrophobic PLGA core and a hydrophilic folate coated PEGlated lipid shell for targeting co-delivery of drug and gene. Hydrophobic drugs can be incorporated into the core and the cationic shell of the drug-loaded nanoparticles can be used to bind DNA. The drug-loaded PLGA/FPL NPs/DNA complexes offer advantages to overcome these problems mentioned above, such as co-delivery of drugs and DNA to improving the chemosensitivity of cancer cells at a gene level, and targeting delivery of drug to the cancer tissue that enhance the bioavailability and reduce the toxicity. The experiment showed that nanoparticles have core-shell structure with nanosize, sustained drug release profile and good DNA-binding ability. Importantly, the core-shell nanoparticles achieve the possibility of co-delivering drugs and genes to the same cells with high gene transfection and drug delivery efficiency. Our data suggest that the PLGA/FPL NPs may be a useful drug and gene co-delivery system. Copyright © 2010 Elsevier Ltd. All rights reserved.
Preparation of recombinant coat protein of Prunus necrotic ringspot virus.
Petrzik, K; Mráz, I; Kubelková, D
2001-02-01
The coat protein (CP) gene of Prunus necrotic ringspot virus (PNRSV) was cloned into pET 16b vector and expressed in Escherichia coli. CP-enriched fractions were prepared from whole cell lysate by differential centrifugation. The fraction sedimenting at 20,000 x g for 30 mins was used for preparation of a rabbit antiserum to CP. This antiserum had a titer of 1:2048 and reacted in a double-antibody sandwich ELISA (DAS-ELISA).
Light Management in Transparent Conducting Oxides by Direct Fabrication of Periodic Surface Arrays
NASA Astrophysics Data System (ADS)
Eckhardt, S.; Sachse, C.; Lasagni, A. F.
Line- and hexagonal-like periodic textures were fabricated on aluminium zinc oxide (AZO) using direct laser interference patterning method. It was found that hexagonally patterned surfaces show a higher performance in both transparency and diffraction properties compared to line-like textured and non-patterned substrates. Furthermore, the electrical resistance of the processed AZO coated substrates remained below the tolerance values for transparent conducting electrodes.
Phan, Jana L; Tucker, Matthew R; Khor, Shi Fang; Shirley, Neil; Lahnstein, Jelle; Beahan, Cherie; Bacic, Antony; Burton, Rachel A
2016-12-01
Xylans are the most abundant non-cellulosic polysaccharide found in plant cell walls. A diverse range of xylan structures influence tissue function during growth and development. Despite the abundance of xylans in nature, details of the genes and biochemical pathways controlling their biosynthesis are lacking. In this study we have utilized natural variation within the Plantago genus to examine variation in heteroxylan composition and structure in seed coat mucilage. Compositional assays were combined with analysis of the glycosyltransferase family 61 (GT61) family during seed coat development, with the aim of identifying GT61 sequences participating in xylan backbone substitution. The results reveal natural variation in heteroxylan content and structure, particularly in P. ovata and P. cunninghamii, species which show a similar amount of heteroxylan but different backbone substitution profiles. Analysis of the GT61 family identified specific sequences co-expressed with IRREGULAR XYLEM 10 genes, which encode putative xylan synthases, revealing a close temporal association between xylan synthesis and substitution. Moreover, in P. ovata, several abundant GT61 sequences appear to lack orthologues in P. cunninghamii. Our results indicate that natural variation in Plantago species can be exploited to reveal novel details of seed coat development and polysaccharide biosynthetic pathways. © The Author 2016. Published by Oxford University Press on behalf of the Society for Experimental Biology.
Drögemüller, Cord; Philipp, Ute; Haase, Bianca; Günzel-Apel, Anne-Rose; Leeb, Tosso
2007-01-01
Coat color dilution in several breeds of dog is characterized by a specific pigmentation phenotype and sometimes accompanied by hair loss and recurrent skin inflammation, the so-called color dilution alopecia or black hair follicular dysplasia. Coat color dilution (d) is inherited as a Mendelian autosomal recessive trait. In a previous study, MLPH polymorphisms showed perfect cosegregation with the dilute phenotype within breeds. However, different dilute haplotypes were found in different breeds, and no single polymorphism was identified in the coding sequence that was likely to be causative for the dilute phenotype. We resequenced the 5'-region of the canine MLPH gene and identified a strong candidate single nucleotide polymorphism within the nontranslated exon 1, which showed perfect association to the dilute phenotype in 65 dilute dogs from 7 different breeds. The A/G polymorphism is located at the last nucleotide of exon 1 and the mutant A-allele is predicted to reduce splicing efficiency 8-fold. An MLPH mRNA expression study using quantitative reverse transcriptase-polymerase chain reaction confirmed that dd animals had only about approximately 25% of the MLPH transcript compared with DD animals. These results provide preliminary evidence that the reported regulatory MLPH mutation might represent a causal mutation for coat color dilution in dogs.
Liu, Rui; Jin, Long; Long, Keren; Chai, Jie; Ma, Jideng; Tang, Qianzi; Tian, Shilin; Hu, Yaodong; Lin, Ling; Wang, Xun; Jiang, Anan; Li, Xuewei; Li, Mingzhou
2016-01-10
Domestication and subsequent selective pressures have produced a large variety of pig coat colors in different regions and breeds. The melanocortin 1 receptor (MC1R) gene plays a crucial role in determining coat color of mammals. Here, we investigated genetic diversity and selection at the coding region of the porcine melanocortin receptor 1 (MC1R) in Tibetan pigs and Landrace pigs. By contrast, genetic variability was much lower in Landrace pigs than in Tibetan pigs. Meanwhile, haplotype analysis showed that Tibetan pigs possessed shared haplotypes, suggesting a possibility of recent introgression event by way of crossbreeding with neighboring domestic pigs or shared ancestral polymorphism. Additionally, we detected positive selection at the MC1R in both Tibetan pigs and Landrace pigs through the dN/dS analysis. These findings suggested that novel phenotypic change (dark coat color) caused by novel mutations may help Tibetan pigs against intensive solar ultraviolet (UV) radiation and camouflage in wild environment, whereas white coat color in Landrace were intentionally selected by human after domestication. Furthermore, both the phylogenetic analysis and the network analysis provided clues that MC1R in Asian and European wild boars may have initially experienced different selective pressures, and MC1R alleles diversified in modern domesticated pigs. Copyright © 2015 Elsevier B.V. All rights reserved.
Nakazawa, Masahiro; Yamada, Masahiro; Wakamura, Masato; Egusa, Hiroshi; Sakurai, Kaoru
Titanium-doped hydroxyapatite (TiHA) nanoparticles contain titanium atoms in the hydroxyapatite lattice, which can physicochemically functionalize the titanium surface without modification of the surface topography. This study aimed to evaluate the physicochemical properties of machined or microroughened titanium surfaces coated with TiHA nanoparticles and the functions of osteoblasts cultured on them. Titanium disks with commercially available surface topography, such as machined or sandblasted, large-grit, and acid-etched (SLA) surfaces, were coated with TiHA. The disks with original or TiHA-coated surfaces were evaluated in topography, wettability, and chemical composition. Osteoblastic cells from rat femurs were cultured on the disks and evaluated in proliferation and differentiation. TiHA coating changed from hydrophobicity to hydrophilicity on both machined and SLA surfaces. Calcium and phosphate atoms were detected all over the surface with TiHA coating regardless of the surface topography. However, the considerable change in the inherent surface topographies was not observed on both types of surfaces after TiHA coating. Osteoblastic proliferative activity at day 4 was increased by TiHA coating on both types of surfaces. TiHA coating did not enhance expressions of bone matrix-related genes such as osteocalcin, osteopontin, bone sialoprotein, alkaline phosphatase, and collagen I. However, depositions of collagen, osteocalcin, and calcium in the culture at days 7 and 20 were increased on both types of surface topographies with TiHA coating. TiHA coating enhanced extracellular matrix formation on smooth and microroughened titanium surfaces by increasing osteoblastic proliferative activity without the deterioration of differentiation through hydrophilic and chemical functionalization.
Voegele, Antje; Linkies, Ada; Müller, Kerstin; Leubner-Metzger, Gerhard
2011-01-01
Germination of endospermic seeds is partly regulated by the micropylar endosperm, which acts as constraint to radicle protrusion. Gibberellin (GA) signalling pathways control coat-dormancy release, endosperm weakening, and organ expansion during seed germination. Three GIBBERELLIN INSENSITIVE DWARF1 (GID1) GA receptors are known in Arabidopsis thaliana: GID1a, GID1b, and GID1c. Molecular phylogenetic analysis of angiosperm GID1s reveals that they cluster into two eudicot (GID1ac, GID1b) groups and one monocot group. Eudicots have at least one gene from each of the two groups, indicating that the different GID1 receptors fulfil distinct roles during plant development. A comparative Brassicaceae approach was used, in which gid1 mutant and whole-seed transcript analyses in Arabidopsis were combined with seed-tissue-specific analyses of its close relative Lepidium sativum (garden cress), for which three GID1 orthologues were cloned. GA signalling via the GID1ac receptors is required for Arabidopsis seed germination, GID1b cannot compensate for the impaired germination of the gid1agid1c mutant. Transcript expression patterns differed temporarily, spatially, and hormonally, with GID1b being distinct from GID1ac in both species. Endosperm weakening is mediated, at least in part, through GA-induced genes encoding cell-wall-modifying proteins. A suppression subtraction hybridization (SSH) cDNA library enriched for sequences that are highly expressed during early germination in the micropylar endosperm contained expansins and xyloglucan endo-transglycosylases/hydrolases (XTHs). Their transcript expression patterns in both species strongly suggest that they are regulated by distinct GID1-mediated GA signalling pathways. The GID1ac and GID1b pathways seem to fulfil distinct regulatory roles during Brassicaceae seed germination and seem to control their downstream targets distinctly. PMID:21778177
de Arruda, Henrique Ferraz; Comin, Cesar Henrique; Miazaki, Mauro; Viana, Matheus Palhares; Costa, Luciano da Fontoura
2015-04-30
A key point in developmental biology is to understand how gene expression influences the morphological and dynamical patterns that are observed in living beings. In this work we propose a methodology capable of addressing this problem that is based on estimating the mutual information and Pearson correlation between the intensity of gene expression and measurements of several morphological properties of the cells. A similar approach is applied in order to identify effects of gene expression over the system dynamics. Neuronal networks were artificially grown over a lattice by considering a reference model used to generate artificial neurons. The input parameters of the artificial neurons were determined according to two distinct patterns of gene expression and the dynamical response was assessed by considering the integrate-and-fire model. As far as single gene dependence is concerned, we found that the interaction between the gene expression and the network topology, as well as between the former and the dynamics response, is strongly affected by the gene expression pattern. In addition, we observed a high correlation between the gene expression and some topological measurements of the neuronal network for particular patterns of gene expression. To our best understanding, there are no similar analyses to compare with. A proper understanding of gene expression influence requires jointly studying the morphology, topology, and dynamics of neurons. The proposed framework represents a first step towards predicting gene expression patterns from morphology and connectivity. Copyright © 2015. Published by Elsevier B.V.
Broadband moth-eye antireflection coatings on silicon
NASA Astrophysics Data System (ADS)
Sun, Chih-Hung; Jiang, Peng; Jiang, Bin
2008-02-01
We report a bioinspired templating technique for fabricating broadband antireflection coatings that mimic antireflective moth eyes. Wafer-scale, subwavelength-structured nipple arrays are directly patterned on silicon using spin-coated silica colloidal monolayers as etching masks. The templated gratings exhibit excellent broadband antireflection properties and the normal-incidence specular reflection matches with the theoretical prediction using a rigorous coupled-wave analysis (RCWA) model. We further demonstrate that two common simulation methods, RCWA and thin-film multilayer models, generate almost identical prediction for the templated nipple arrays. This simple bottom-up technique is compatible with standard microfabrication, promising for reducing the manufacturing cost of crystalline silicon solar cells.
Bioinspired broadband antireflection coatings on GaSb
NASA Astrophysics Data System (ADS)
Min, Wei-Lun; Betancourt, Amaury P.; Jiang, Peng; Jiang, Bin
2008-04-01
We report an inexpensive yet scalable templating technique for fabricating moth-eye antireflection gratings on gallium antimonide substrates. Non-close-packed colloidal monolayers are utilized as etching masks to pattern subwavelength-structured nipple arrays on GaSb. The resulting gratings exhibit superior broadband antireflection properties and thermal stability than conventional multilayer dielectric coatings. The specular reflection of the templated nipple arrays match with the theoretical predictions using a rigorous coupled-wave analysis model. The effect of the nipple shape and size on the antireflection properties has also been investigated by the same model. These biomimetic coatings are of great technological importance in developing efficient thermophotovoltaic cells.
Cicada-Wing-Inspired Self-Cleaning Antireflection Coatings on Polymer Substrates.
Chen, Ying-Chu; Huang, Zhe-Sheng; Yang, Hongta
2015-11-18
The cicada has transparent wings with remarkable self-cleaning properties and high transmittance over the whole visible spectral range, which is derived from periodic conical structures covering the wing surface. Here we report a scalable self-assembly technique for fabricating multifunctional optical coatings that mimic cicada-wing structures. Spin-coated two-dimensional non-close-packed colloidal crystals are utilized as etching masks to pattern subwavelength-structured cone arrays directly on polymer substrates. The resulting gratings exhibit broadband antireflection performance and superhydrophobic properties after surface modification. The dependence of the cone shape and size on the antireflective and self-cleaning properties has also been investigated in this study.
NASA Astrophysics Data System (ADS)
Ashley, J. W.; Herkenhoff, K. E.; Golombek, M. P.; Johnson, J. R.
2012-12-01
Meteorites found on Mars provide valuable insights into martian surface processes. During the course of Mars Exploration Rover (MER) extended missions, Spirit and Opportunity have identified 17 confirmed and candidate meteorites on Mars, most of which are irons. The iron meteorites exhibit morphologies and coatings that communicate complex post-fall exposure histories relevant to an understanding of climate near the martian equator [1-4]. Both chemical and mechanical weathering effects are represented. Among the more significant of these are: 1) cm-scale hollowing, 2) surficial rounding, 3) mass excavation/dissolution and removal, 4) differential etching of kamacite plates and taenite lamellae, revealing Widmanstätten patterns, 5) discontinuous iron oxide coatings, and 6) the effects of cavernous weathering, which often penetrate to rock interiors. Determining the nature, magnitude, and timing of each process and its associated features is a complex problem that will be aided by laboratory experiments, image processing, and careful surface evaluation. Because some features appear to superpose others in ways analogous to stratigraphic relationships, Microscopic Imager (MI) mosaics are useful for sketching "geologic maps" of meteorite surfaces. Employing the techniques of conventional planetary mapping [5], each map was drafted manually using full-resolution MI mosaics and Adobe Photoshop software. Units were selected to represent the oxide coating, dust-coated surfaces, sand-coated surfaces, taenite lamellae, and uncoated metal. Also included are areas in shadow, and regions of blooming caused by specular reflection of metal. Regmaglypt rim crests are presented as lineations. As with stratigraphic relationships, noting embayments and other cross-cutting relationships assists with establishing the relative timing for observed weathering effects. In addition to suggesting alternating sequences of wind and water exposure [1], patterns in oxide coating occurrence show evidence that coating deposition (interpreted as a result of water interaction) was geologically recent: Because the margins of many oxide coating deposits are concentric to and slightly removed from regmaglypt rim crests, the latest cycle is interpreted as a time of coating removal, not deposition, with these topographic high points representing zones of greatest erosional attack. Assuming the oxide coating has a low to moderate hardness, this observation implies relative geologic youth for the coating. However, it is unknown whether oxide deposits are stable or actively eroded by free basaltic sand grains [e.g., 6] in the modern epoch. The high science return from ongoing meteorite studies at MER landing sites supports their consideration if meteorites are also encountered by the Mars Science Laboratory Curiosity rover in Gale Crater.
Ordered CdSe nanoparticles within self-assembled block copolymer domains on surfaces.
Zou, Shan; Hong, Rui; Emrick, Todd; Walker, Gilbert C
2007-02-13
Hierarchical, high-density, ordered patterns were fabricated on Si substrates by self-assembly of CdSe nanoparticles within approximately 20-nm-thick diblock copolymer films in a controlled manner. Surface-modified CdSe nanoparticles formed well-defined structures within microphase-separated polystyrene-b-poly(2-vinylpyridine) (PS-b-P2VP) domains. Trioctylphosphine oxide (TOPO)-coated CdSe nanoparticles were incorporated into PS domains and polyethylene glycol-coated CdSe nanoparticles were located primarily in the P2VP domains. Nearly close-packed CdSe nanoparticles were clearly identified within the highly ordered patterns on Si substrates by scanning electron microscopy (SEM). Contact angle measurements together with SEM results indicate that TOPO-CdSe nanoparticles were partially placed at the air/copolymer interface.
NASA Astrophysics Data System (ADS)
Borzenkov, Mykola; Chirico, Giuseppe; Collini, Maddalena; Määttänen, Anni; Ihalainen, Petri; Cabrini, Elisa; Dacarro, Giacomo; Pallavicini, Piersandro
2016-04-01
The research and development of personalized medical treatments is increasing steadily fostered by its large societal impact. The ability of non-spherical gold nanoparticles to locally and efficiently release heat when irradiated in Near Infrared (NIR) wavelength region is a promising tool for photothermal medical therapies. In the present work, stable inks containing PEGylated gold nanostars (GNS) were obtained and inkjet-printed on a pigment coated paper substrate. Significant photothermal effect of the printed patterns was observed under Near Infrared (NIR) excitation of the Localized Surface Plasmon Resonance (LSPR) of the GNS. These preliminary results support, in perspective, the application of printed GNS patterns for thermal medical treatments either by direct localized heating, or by temperature triggered drug release.
Friction enhancement via micro-patterned wet elastomer adhesives on small intestinal surfaces.
Kwon, Jiwoon; Cheung, Eugene; Park, Sukho; Sitti, Metin
2006-12-01
A micro-pillar-based silicone rubber adhesive coated with a thin silicone oil layer is investigated in this paper for developing friction-based clamping mechanisms for robotic endoscopic microcapsules. These adhesives are shown to enhance the frictional force between the capsule and the intestinal wall by a factor of about seven over a non-patterned flat elastomer material. In this study, tests performed on fresh samples of pig small intestine are used to optimize the diameter of the micro-pillars to maximize the frictional forces. In addition, the effects of other factors such as the oil viscosity and applied normal forces are investigated. It is demonstrated that the proposed micro-pillar pattern based elastomer adhesive exhibits a maximal frictional force when the pillar diameter is 140 microm and coated silicon oil has a very high viscosity (10,000 cSt). It is also found that the frictional force of the micro-patterned adhesive increases nonlinearly in proportion to the applied normal force. These adhesives would be used as a robust attachment material for developing robotic capsule endoscopes inside intestines with clamping capability.
Friction enhancement via micro-patterned wet elastomer adhesives on small intestinal surfaces
NASA Astrophysics Data System (ADS)
Kwon, Jiwoon; Cheung, Eugene; Park, Sukho; Sitti, Metin
2006-12-01
A micro-pillar-based silicone rubber adhesive coated with a thin silicone oil layer is investigated in this paper for developing friction-based clamping mechanisms for robotic endoscopic microcapsules. These adhesives are shown to enhance the frictional force between the capsule and the intestinal wall by a factor of about seven over a non-patterned flat elastomer material. In this study, tests performed on fresh samples of pig small intestine are used to optimize the diameter of the micro-pillars to maximize the frictional forces. In addition, the effects of other factors such as the oil viscosity and applied normal forces are investigated. It is demonstrated that the proposed micro-pillar pattern based elastomer adhesive exhibits a maximal frictional force when the pillar diameter is 140 µm and coated silicon oil has a very high viscosity (10 000 cSt). It is also found that the frictional force of the micro-patterned adhesive increases nonlinearly in proportion to the applied normal force. These adhesives would be used as a robust attachment material for developing robotic capsule endoscopes inside intestines with clamping capability.
Fox (forkhead) genes are involved in the dorso-ventral patterning of the Xenopus mesoderm.
El-Hodiri, H; Bhatia-Dey, N; Kenyon, K; Ault, K; Dirksen, M; Jamrich, M
2001-01-01
Fox (forkhead/winged helix) genes encode a family of transcription factors that are involved in embryonic pattern formation, regulation of tissue specific gene expression and tumorigenesis. Several of them are transcribed during Xenopus embryogenesis and are important for the patterning of ectoderm, mesoderm and endoderm. We have isolated three forkhead genes that are activated during gastrulation and play an important role in the dorso-ventral patterning of the mesoderm. XFKH1 (FoxA4b), the first vertebrate forkhead gene to be implicated in embryonic pattern formation, is expressed in the Spemann-Mangold organizer region and later in the embryonic notochord. XFKH7, the Xenopus orthologue of the murine Mfh1(Foxc2), is expressed in the presomitic mesoderm, but not in the notochord or lateral plate mesoderm. Finally, XFD-13'(FoxF1b)1 is expressed in the lateral plate mesoderm, but not in the notochord or presomitic mesoderm. Expression pattern and functional experiments indicate that these three forkhead genes are involved in the dorso-ventral patterning of the mesoderm.
Prasolova, L A; Trut, L N; Os'kina, I N; Gulevich, R G; Pliusnina, I Z; Vsevolodov, E B; Latypov, I F
2006-01-01
The effect of methyl supplements to the diet of pregnant homozygous (AAHH) female rats with agouti coat color mated with homozygous (aahh) males on the phenotypic modification of the coat color of their heterozygous offspring (AaHh) has been studied. Comparative morphological analysis of the main parameters of hair that determine coat color, including the total length of hairs of different types and the length of the upper black (eumelanin) and light (pheomelanin) parts of awn hairs has been performed. The pattern of pigment granule distribution among hair layers has been analyzed. The melanin content of the hair has been determined using electron spin resonance (ESR). Although all offspring have a typical agouti coat color (alternating black and light portions of hair), 39% of them have a darker coat color than control and other experimental rats have. The main differences between the offspring with darkened and standard coat colors are accounted for by the ratio between the eumelanin and pheomelanin portions of awn hairs. In darkened offspring, this ratio is significantly higher than in control rats. The possible mechanisms of the phenotypic modification of agouti coat color in experimental animals are discussed.
Synthesis of superparamagnetic silica-coated magnetite nanoparticles for biomedical applications
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kaur, Navjot, E-mail: navjot.dhindsa2989@gmail.com; Chudasama, Bhupendra, E-mail: bnchudasama@gmail.com
Multifunctional superparamagnetic iron oxide nanoparticles (SPIONs) coated with silica are widely researched for biomedical applications such as magnetic resonance imaging, tissue repair, cell separation, hyperthermia, drug delivery, etc. In this article synthesis of magnetite (Fe{sub 3}O{sub 4}) nanoparticles and their coating with SiO{sub 2} is reported. Fe{sub 3}O{sub 4} nanoparticles were synthesized by chemical co-precipitation and it was coated with silica by hydrolysis and condensation of tetraethylorthosilicate. XRD, FTIR, TEM and VSM techniques were used to characterize bare and coated nanoparticles. Results indicated that the average size of SPIONS was 8.4 nm. X-ray diffraction patterns of silica coated SPIONS were identicalmore » to that of SPIONS confirming the inner spinal structure of SPIONS. FTIR results confirmed the binding of silica with the magnetite and the formation of the silica shell around the magnetite core. Magnetic properties of SPIONS and silica coated SPIONS are determined by VSM. They are superparamagnetic. The major conclusion drawn from this study is that the synthesis route yields stable, non-aggregated magnetite-silica core-shell nanostructures with tailored morphology and excellent magnetic properties.« less
Poly(dimethylsiloxane) coatings for controlled drug release--polymer modifications.
Schulze Nahrup, J; Gao, Z M; Mark, J E; Sakr, A
2004-02-11
Modifications of endhydroxylated poly(dimethylsiloxane) (PDMS) formulations were studied for their ability to be applied onto tablet cores in a spray-coating process and to control drug release in zero-order fashion. Modifications of the crosslinker from the most commonly used tetraethylorthosilicate (TEOS) to the trifunctional 3-(2,3-epoxypropoxy)propyltrimethoxysilane (SIG) and a 1:1 mixture of the two were undertaken. Addition of methylpolysiloxane-copolymers were studied. Lactose, microcrystalline cellulose (MCC) and polyethylene glycol 8000 (PEG) were the channeling agents applied. The effects on dispersion properties were characterized by particle size distribution and viscosity. Mechanical properties of resulting free films were studied to determine applicability in a pan-coating process. Release of hydrochlorothiazide (marker drug) was studied from tablets coated in a lab-size conventional coating pan. All dispersions were found suitable for a spray-coating process. Preparation of free films showed that copolymer addition was not possible due to great decline in mechanical properties. Tablets coated with formulations containing PEG were most suitable to control drug release, at only 5% coating weight. Constant release rates could be achieved for formulations with up to 25% PEG; higher amounts resulted in a non-linear release pattern. Upon adding 50% PEG, a drug release of 63% over 24 h could be achieved.
Spore coat protein synthesis in cell-free systems from sporulating cells of Bacillus subtilis.
Nakayama, T; Munoz, L E; Sadaie, Y; Doi, R H
1978-09-01
Cell-free systems for protein synthesis were prepared from Bacillus subtilis 168 cells at several stages of sporulation. Immunological methods were used to determine whether spore coat protein could be synthesized in the cell-free systems prepared from sporulating cells. Spore coat protein synthesis first occurred in extracts from stage t2 cells. The proportion of spore coat protein to total proteins synthesized in the cell-free systems was 2.4 and 3.9% at stages t2 and t4, respectively. The sodium dodecyl sulfate-urea-polyacrylamide gel electrophoresis patterns of immunoprecipitates from the cell-free systems showed the complete synthesis of an apparent spore coat protein precursor (molecular weight, 25,000). A polypeptide of this weight was previously identified in studies in vivo (L.E. Munoz, Y. Sadaie, and R.H. Doi, J. Biol. Chem., in press). The synthesis in vitro of polysome-associated nascent spore coat polypeptides with varying molecular weights up to 23,000 was also detected. These results indicate that the spore coat protein may be synthesized as a precursor protein. The removal of proteases in the crude extracts by treatment with hemoglobin-Sepharose affinity techniques may be preventing the conversion of the large 25,000-dalton precursor to the 12,500-dalton mature spore coat protein.
The biological response to laser-aided direct metal-coated Titanium alloy (Ti6Al4V)
Shin, T.; Lim, D.; Kim, Y. S.; Kim, S. C.; Jo, W. L.
2018-01-01
Objectives Laser-engineered net shaping (LENS) of coated surfaces can overcome the limitations of conventional coating technologies. We compared the in vitro biological response with a titanium plasma spray (TPS)-coated titanium alloy (Ti6Al4V) surface with that of a Ti6Al4V surface coated with titanium using direct metal fabrication (DMF) with 3D printing technologies. Methods The in vitro ability of human osteoblasts to adhere to TPS-coated Ti6Al4V was compared with DMF-coating. Scanning electron microscopy (SEM) was used to assess the structure and morphology of the surfaces. Biological and morphological responses to human osteoblast cell lines were then examined by measuring cell proliferation, alkaline phosphatase activity, actin filaments, and RUNX2 gene expression. Results Morphological assessment of the cells after six hours of incubation using SEM showed that the TPS- and DMF-coated surfaces were largely covered with lamellipodia from the osteoblasts. Cell adhesion appeared similar in both groups. The differences in the rates of cell proliferation and alkaline phosphatase activities were not statistically significant. Conclusions The DMF coating applied using metal 3D printing is similar to the TPS coating, which is the most common coating process used for bone ingrowth. The DMF method provided an acceptable surface structure and a viable biological surface. Moreover, this method is automatable and less complex than plasma spraying. Cite this article: T. Shin, D. Lim, Y. S. Kim, S. C. Kim, W. L. Jo, Y. W. Lim. The biological response to laser-aided direct metal-coated Titanium alloy (Ti6Al4V). Bone Joint Res 2018;7:357–361. DOI: 10.1302/2046-3758.75.BJR-2017-0222.R1. PMID:29922456
A novel method for accurate patterning and positioning of biological cells
NASA Astrophysics Data System (ADS)
Jing, Gaoshan; Labukas, Joseph P.; Iqbal, Aziz; Perry, Susan Fueshko; Ferguson, Gregory S.; Tatic-Lucic, Svetlana
2007-05-01
The ability to anchor cells in predefined patterns on a surface has become very important for the development of cell-based sensors, tissue-engineering applications, and the understanding of basic cell functions. Currently, the most widely used technique to generate micrometer or sub-micrometer-sized patterns for various biological applications is microcontact printing (μCP). However, the fidelity of the final pattern may be compromised by deformation of the PDMS stamps used during printing. A novel technique for accurately patterning and positioning biological cells is presented, which can overcome this obstacle. We have fabricated a chip on a silicon wafer using standard photolithographic and deposition processes consisting of gold patterns on top of PECVD silicon dioxide. A hydrophobic self-assembled monolayer (SAM) derived from 1-hexadecanethiol (HDT) was coated on the gold surface to prevent cell growth, and a hydrophilic SAM derived from (3-trimethoxysilyl propyl)-diethylenetriamine (DETA) was coated on the exposed PECVD silicon dioxide surface to promote cell growth. Immortalized mouse hypothalamic neurons (GT1-7) were cultured in vitro on the chip, and patterned cells were fluorescently stained and visualized by fluorescence microscopy. By our method, hydrophobic and hydrophilic regions can be reliably generated and easily visualized under a microscope prior to cell culturing. Cell growth was precisely controlled and limited to specific areas. The achieved resolution was 2 microns, and it could be improved with high resolution photolithographic methods.
Enhanced protein adsorption and patterning on nanostructured latex-coated paper.
Juvonen, Helka; Määttänen, Anni; Ihalainen, Petri; Viitala, Tapani; Sarfraz, Jawad; Peltonen, Jouko
2014-06-01
Specific interactions of extracellular matrix proteins with cells and their adhesion to the substrate are important for cell growth. A nanopatterned latex-coated paper substrate previously shown to be an excellent substrate for cell adhesion and 2D growth was studied for directed immobilization of proteins. The nanostructured latex surface was formed by short-wavelength IR irradiation of a two-component latex coating consisting of a hydrophilic film-forming styrene butadiene acrylonitrile copolymer and hydrophobic polystyrene particles. The hydrophobic regions of the IR-treated latex coating showed strong adhesion of bovine serum albumin (cell repelling protein), fibronectin (cell adhesive protein) and streptavidin. Opposite to the IR-treated surface, fibronectin and streptavidin had a poor affinity toward the untreated pristine latex coating. Detailed characterization of the physicochemical surface properties of the latex-coated substrates revealed that the observed differences in protein affinity were mainly due to the presence or absence of the protein repelling polar and charged surface groups. The protein adsorption was assisted by hydrophobic (dehydration) interactions. Copyright © 2014 Elsevier B.V. All rights reserved.
Chen, Li-Qing; Lin, I Winnie; Qu, Xiao-Qing; Sosso, Davide; McFarlane, Heather E.; Londoño, Alejandra; Samuels, A. Lacey; Frommer, Wolf B.
2015-01-01
Developing plant embryos depend on nutrition from maternal tissues via the seed coat and endosperm, but the mechanisms that supply nutrients to plant embryos have remained elusive. Sucrose, the major transport form of carbohydrate in plants, is delivered via the phloem to the maternal seed coat and then secreted from the seed coat to feed the embryo. Here, we show that seed filling in Arabidopsis thaliana requires the three sucrose transporters SWEET11, 12, and 15. SWEET11, 12, and 15 exhibit specific spatiotemporal expression patterns in developing seeds, but only a sweet11;12;15 triple mutant showed severe seed defects, which include retarded embryo development, reduced seed weight, and reduced starch and lipid content, causing a “wrinkled” seed phenotype. In sweet11;12;15 triple mutants, starch accumulated in the seed coat but not the embryo, implicating SWEET-mediated sucrose efflux in the transfer of sugars from seed coat to embryo. This cascade of sequentially expressed SWEETs provides the feeding pathway for the plant embryo, an important feature for yield potential. PMID:25794936
He, Xinkuai; Zhang, Chuang; Zhu, Qingyun; Lu, Haozi; Cai, Youxing; Wu, Luye
2017-02-01
The electrodeposition of nanocrystalline Ni–Fe alloy coatings and associated nucleation/growth processes are investigated on the glassy carbon (GC) electrode in 1-butyl-3-methylimidazolium-hydrogen sulfate ([BMIM]HSO4) ionic liquid (IL). Cyclic voltammetric data suggest that the co-electrodeposition of Ni–Fe alloys is quasi-reversible. Moreover, chronoamperometry results indicate that the electrodeposition proceeds via a simultaneous nucleation and three-dimensional growth mechanism. In addition, the effects of electrodeposition potential and electrolyte temperature on the coating thickness and Fe content are also studied. The microstructure and composition of the Ni–Fe alloy coatings on Cu substrate are investigated using scanning electron microscopy (SEM), X-ray diffraction (XRD) and energy-dispersive spectroscopy (EDS). SEM observations show that these electrodeposits present a dense and compact structure, EDS analysis indicates that the coatings are composed of Ni and Fe, XRD pattern shows the coatings are crystalline with a face-centred cubic (fcc) structure. Tafel plots reveal that the Ni–Fe alloy prepared from [BMIM]HSO4 IL presents better corrosion resistance than that of pure Ni.
Yuk, Soon Hong; Oh, Keun Sang; Park, Jinah; Kim, Soon-Joong; Kim, Jung Ho; Kwon, Il Keun
2012-04-01
The mixture of poly(lactide-co-glycolide) (PLGA) and poly(ethylene vinyl acetate) (PEVA) forms a homogeneous liquid in an organic solvent such as tetrahydrofuran, and a phase-separated PLGA/PEVA composite can be prepared from it by evaporating the organic solvent. Exploiting this phenomenon, we designed a novel method of preparing a drug-loaded PLGA/PEVA composite and used it for coating drug-eluting stents (DESs). Paclitaxel (PTX), an anticancer drug, was chosen as a model drug. PLGA acts as a microdepot for PTX, and PEVA provides mechanical strength to the coating material. The presence of PLGA in the PLGA/PEVA composite suppressed PTX crystallization in the coating material, and PTX showed a sustained release rate over more than 30 days. The mechanical strength of the PLGA/PEVA composite was better than that of PEVA used as a control. After coating the stent with a PLGA/PEVA composite using ultrasonic atomizing spray, the morphology of the coated material was observed by scanning electron microscopy, and the release pattern of PTX was measured by high-performance liquid chromatography.
Yuk, Soon Hong; Oh, Keun Sang; Park, Jinah; Kim, Soon-Joong; Kim, Jung Ho; Kwon, Il Keun
2012-01-01
The mixture of poly(lactide-co-glycolide) (PLGA) and poly(ethylene vinyl acetate) (PEVA) forms a homogeneous liquid in an organic solvent such as tetrahydrofuran, and a phase-separated PLGA/PEVA composite can be prepared from it by evaporating the organic solvent. Exploiting this phenomenon, we designed a novel method of preparing a drug-loaded PLGA/PEVA composite and used it for coating drug-eluting stents (DESs). Paclitaxel (PTX), an anticancer drug, was chosen as a model drug. PLGA acts as a microdepot for PTX, and PEVA provides mechanical strength to the coating material. The presence of PLGA in the PLGA/PEVA composite suppressed PTX crystallization in the coating material, and PTX showed a sustained release rate over more than 30 days. The mechanical strength of the PLGA/PEVA composite was better than that of PEVA used as a control. After coating the stent with a PLGA/PEVA composite using ultrasonic atomizing spray, the morphology of the coated material was observed by scanning electron microscopy, and the release pattern of PTX was measured by high-performance liquid chromatography. PMID:27877483
NASA Astrophysics Data System (ADS)
Yuk, Soon Hong; Oh, Keun Sang; Park, Jinah; Kim, Soon-Joong; Kim, Jung Ho; Kwon, Il Keun
2012-04-01
The mixture of poly(lactide-co-glycolide) (PLGA) and poly(ethylene vinyl acetate) (PEVA) forms a homogeneous liquid in an organic solvent such as tetrahydrofuran, and a phase-separated PLGA/PEVA composite can be prepared from it by evaporating the organic solvent. Exploiting this phenomenon, we designed a novel method of preparing a drug-loaded PLGA/PEVA composite and used it for coating drug-eluting stents (DESs). Paclitaxel (PTX), an anticancer drug, was chosen as a model drug. PLGA acts as a microdepot for PTX, and PEVA provides mechanical strength to the coating material. The presence of PLGA in the PLGA/PEVA composite suppressed PTX crystallization in the coating material, and PTX showed a sustained release rate over more than 30 days. The mechanical strength of the PLGA/PEVA composite was better than that of PEVA used as a control. After coating the stent with a PLGA/PEVA composite using ultrasonic atomizing spray, the morphology of the coated material was observed by scanning electron microscopy, and the release pattern of PTX was measured by high-performance liquid chromatography.
NASA Astrophysics Data System (ADS)
Roknian, Masoud; Fattah-alhosseini, Arash; Gashti, Seyed Omid
2018-03-01
Plasma electrolytic oxidation has been used as a relatively new method for applying ceramic coatings having different features. In the present study, commercially pure titanium is used as substrate, and effects of trisodium phosphate electrolyte concentration on the microstructure, as well as corrosion behavior of the coating in Ringer's physiological solution are investigated. The morphology and phase compositions of coatings were analyzed by using scanning electron microscopy (SEM) and x-ray diffraction patterns. The study on the corrosion behavior of samples in a Ringer's physiological solution was carried out using open-circuit potential potentiodynamic polarization and electrochemical impedance spectroscopy. The results of electrochemical analysis proved that higher concentration of phosphate electrolyte leads to increase in the corrosion resistance of applied coatings. Accordingly, obtained results revealed that the optimum electrolyte concentration for the best corrosion behavior was 20 g L-1. Furthermore, SEM images and reduction in the dielectric breakdown potential indicated that increase in the electrolyte concentration leads to morphological improvement and smoothening of the surface.
Corrosion behavior of HVOF coated sheets
NASA Astrophysics Data System (ADS)
Yilbas, B. S.; Abdul-Aleem, B. J.; Khalid, M.
2003-12-01
High velocity oxygen-fuel (HVOF) thermal spray coating finds application in industry due to its superior resistance to corrosion and thermal loading. In the HVOF process, the metallic powders at elevated temperature are sprayed at supersonic speed onto a substrate material. The powder granules sprayed impact onto each other, forming a mechanical bonding across the coating layer. In most of the cases, the distances among the particles (powder granules sprayed) are not the same, which in turn results in inhomogeneous structure across the coating layer. Moreover, the rate of oxidation of the powder granules during the spraying process varies. Consequently, the electrochemical response of the coating layer surfaces next to the base material and free to atmosphere differs. In the current study, the electrochemical response of a coating sheet formed during HVOF thermal spraying was investigated. NiCrMoNb alloy (similar to Inconel 625) wass used for the powder granules. Thermal spraying was carried out onto a smooth surface of stainless steel workpiece (without grid blasting), and later the coating layer was removed from the surface to obtain the coating sheet for the electrochemical tests. It was found that the corrosion rate of the smooth surface (surface next to the stainless steel surface before its removal) is considerably larger than that corresponding to the rough surface (free surface) of the coating sheet, and no specific patterns were observed for the pit sites.
Materials Approach to Dissecting Surface Responses in the Attachment Stages of Biofouling Organisms
2016-04-25
their settlement behavior in regards to the coating surfaces. 5) Multivariate statistical analysis was used to examine the effect (if any) of the...applied to glass rods and were deployed in the field to evaluate settlement preferences. Canonical Analysis of Principal Coordinates were applied to...the influence of coating surface properties on the patterns in settlement observed in the field in the extension of this work over the coming year
Development of a Biosensor Nanofluidic Platform for Integration with Terahertz Spectroscopic System
2014-06-27
space. The instrumentation for fabrication of micro/nano-fluidic chips including a Laser-Cutting System, a Sputtering system, a Spin Coating ...polyester (PET) substrate, as PET is more chemically and thermally resistant, and can be readily obtained in a variety of thicknesses down to 12.5 um...to create the array pattern on the silver coated PET substrate. Copper was then electrodeposited to a thickness of 5 um around the photoresist
Transient expression of GUS in bombarded embryogenic longleaf, loblolly, and eastern white pine
Alex M. Diner; Allan Zipf; Rufina Ward; Yinghua Huang; George Brown
1999-01-01
Embryogenic tissue cultures derived from immature zygotic embryos of longleaf, loblolly, and eastern white pine were maintained in culture for up to 2 years, then bombarded with gold particles coated with a gene construct containing the GUS reporter gene fused to an adenine methyltransferase promoter from an algal virus. Physiological expression of GUS was observed in...
Cannat, A; Feingold, N; Caffin, J C; Serre, A
1979-01-01
A peptidoglycan containing fraction (fraction "5") extracted from Brucella melitensis has been injected in low infra-vaccinating doses into inbred mice. The genetic control of the resulting anti-Brucella humoral response has been studied in the C57BL/6 "good responder" X DBA2 "low responder" model. The results observed in F1, F2 and reciprocal backcrosses show that the "good responder" character, although transmitted as a dominant trait, is under polygenic control and independent of H2 haplotype, Ig allotype, sexual chromosoms or the "d" coat color gene. On the other hand, the phenotypic expression of at least one of the genes involved is sex-limited and influenced by hormonal environmental factors. Moreover the expression in females of one of these sex-dependent genes is associated with the "b" coat color gene. These results are discussed in terms of their possible relevance in spontaneous or vaccinal resistance to experimental brucellosis, of the relative role of the peptidoglycan and lipoprotein moieties in fraction "5" and of the possible importance of sex-dependent and chromosome 4-linked genetic factors for B-cell functions.
Cifuentes-Rius, Anna; Boase, Nathan R B; Font, Ines; Coronas, Nuria; Ramos-Perez, Victor; Thurecht, Kristofer J; Borrós, Salvador
2017-04-05
Gene therapy has arisen as a pioneering technique to treat diseases by direct employment of nucleic acids as medicine. The major historical problem is to develop efficient and safe systems for the delivery of therapeutic genes into the target cells. Carbon nanotubes (CNTs) have demonstrated considerable promise as delivery vectors due to their (i) high aspect ratio and (ii) capacity to translocate through plasma membranes, known as the nanoneedle effect. To leverage these advantages, close attention needs to be paid to the physicochemical characteristics of the CNTs used. CNTs with different diameters (thinner and thicker) were treated by chemical oxidation to produce shorter fragments. Rigid (thick) and flexible (thin) CNTs, and their shortened versions, were coated with polyallylamine (ppAA) by plasma-enhanced chemical vapor deposition. The ppAA coating leads to a positively charged CNT surface that is able to electrostatically bind the green fluorescent protein plasmid reporter. This study shows how rigidity and length can affect their (i) behavior in biological media, (ii) ability to transfect in vitro, and (iii) biodistribution in vivo. This study also generates a set of basic design rules for the development of more efficient CNT-based gene-delivery vectors.
Renouard, Sullivan; Tribalatc, Marie-Aude; Lamblin, Frederic; Mongelard, Gaëlle; Fliniaux, Ophélie; Corbin, Cyrielle; Marosevic, Djurdjica; Pilard, Serge; Demailly, Hervé; Gutierrez, Laurent; Hano, Christophe; Mesnard, François; Lainé, Eric
2014-09-15
RNAi technology was applied to down regulate LuPLR1 gene expression in flax (Linum usitatissimum L.) seeds. This gene encodes a pinoresinol lariciresinol reductase responsible for the synthesis of (+)-secoisolariciresinol diglucoside (SDG), the major lignan accumulated in the seed coat. If flax lignans biological properties and health benefits are well documented their roles in planta remain unclear. This loss of function strategy was developed to better understand the implication of the PLR1 enzyme in the lignan biosynthetic pathway and to provide new insights on the functions of these compounds. RNAi plants generated exhibited LuPLR1 gene silencing as demonstrated by quantitative RT-PCR experiments and the failed to accumulate SDG. The accumulation of pinoresinol the substrate of the PLR1 enzyme under its diglucosylated form (PDG) was increased in transgenic seeds but did not compensate the overall loss of SDG. The monolignol flux was also deviated through the synthesis of 8-5' linked neolignans dehydrodiconiferyl alcohol glucoside (DCG) and dihydro-dehydrodiconiferyl alcohol glucoside (DDCG) which were observed for the first time in flax seeds. Copyright © 2014 Elsevier GmbH. All rights reserved.
USDA-ARS?s Scientific Manuscript database
Organ formation relies upon precise patterns of gene expression that are under tight spatial and temporal regulation. Transcription patterns are specified by several cellular processes during development, including chromatin remodeling, but little is known about how chromatin remodeling factors cont...
Liu, Gangbiao; Zou, Yangyun; Cheng, Qiqun; Zeng, Yanwu; Gu, Xun; Su, Zhixi
2014-04-01
The age distribution of gene duplication events within the human genome exhibits two waves of duplications along with an ancient component. However, because of functional constraint differences, genes in different functional categories might show dissimilar retention patterns after duplication. It is known that genes in some functional categories are highly duplicated in the early stage of vertebrate evolution. However, the correlations of the age distribution pattern of gene duplication between the different functional categories are still unknown. To investigate this issue, we developed a robust pipeline to date the gene duplication events in the human genome. We successfully estimated about three-quarters of the duplication events within the human genome, along with the age distribution pattern in each Gene Ontology (GO) slim category. We found that some GO slim categories show different distribution patterns when compared to the whole genome. Further hierarchical clustering of the GO slim functional categories enabled grouping into two main clusters. We found that human genes located in the duplicated copy number variant regions, whose duplicate genes have not been fixed in the human population, were mainly enriched in the groups with a high proportion of recently duplicated genes. Moreover, we used a phylogenetic tree-based method to date the age of duplications in three signaling-related gene superfamilies: transcription factors, protein kinases and G-protein coupled receptors. These superfamilies were expressed in different subcellular localizations. They showed a similar age distribution as the signaling-related GO slim categories. We also compared the differences between the age distributions of gene duplications in multiple subcellular localizations. We found that the distribution patterns of the major subcellular localizations were similar to that of the whole genome. This study revealed the whole picture of the evolution patterns of gene functional categories in the human genome.
Gibbons, Taylor C; Metzger, David C H; Healy, Timothy M; Schulte, Patricia M
2017-05-01
Phenotypic plasticity is thought to facilitate the colonization of novel environments and shape the direction of evolution in colonizing populations. However, the relative prevalence of various predicted patterns of changes in phenotypic plasticity following colonization remains unclear. Here, we use a whole-transcriptome approach to characterize patterns of gene expression plasticity in the gills of a freshwater-adapted and a saltwater-adapted ecotype of threespine stickleback (Gasterosteus aculeatus) exposed to a range of salinities. The response of the gill transcriptome to environmental salinity had a large shared component common to both ecotypes (2159 genes) with significant enrichment of genes involved in transmembrane ion transport and the restructuring of the gill epithelium. This transcriptional response to freshwater acclimation is induced at salinities below two parts per thousand. There was also differentiation in gene expression patterns between ecotypes (2515 genes), particularly in processes important for changes in the gill structure and permeability. Only 508 genes that differed between ecotypes also responded to salinity and no specific processes were enriched among this gene set, and an even smaller number (87 genes) showed evidence of changes in the extent of the response to salinity acclimation between ecotypes. No pattern of relative expression dominated among these genes, suggesting that neither gains nor losses of plasticity dominated the changes in expression patterns between the ecotypes. These data demonstrate that multiple patterns of changes in gene expression plasticity can occur following colonization of novel habitats. © 2017 John Wiley & Sons Ltd.
Zhang, Zhang; Liu, Jingxing; Wu, Jiayan; Yu, Jun
2013-01-01
The regulation of gene expression is essential for eukaryotes, as it drives the processes of cellular differentiation and morphogenesis, leading to the creation of different cell types in multicellular organisms. RNA-Sequencing (RNA-Seq) provides researchers with a powerful toolbox for characterization and quantification of transcriptome. Many different human tissue/cell transcriptome datasets coming from RNA-Seq technology are available on public data resource. The fundamental issue here is how to develop an effective analysis method to estimate expression pattern similarities between different tumor tissues and their corresponding normal tissues. We define the gene expression pattern from three directions: 1) expression breadth, which reflects gene expression on/off status, and mainly concerns ubiquitously expressed genes; 2) low/high or constant/variable expression genes, based on gene expression level and variation; and 3) the regulation of gene expression at the gene structure level. The cluster analysis indicates that gene expression pattern is higher related to physiological condition rather than tissue spatial distance. Two sets of human housekeeping (HK) genes are defined according to cell/tissue types, respectively. To characterize the gene expression pattern in gene expression level and variation, we firstly apply improved K-means algorithm and a gene expression variance model. We find that cancer-associated HK genes (a HK gene is specific in cancer group, while not in normal group) are expressed higher and more variable in cancer condition than in normal condition. Cancer-associated HK genes prefer to AT-rich genes, and they are enriched in cell cycle regulation related functions and constitute some cancer signatures. The expression of large genes is also avoided in cancer group. These studies will help us understand which cell type-specific patterns of gene expression differ among different cell types, and particularly for cancer. PMID:23382867
Discover mouse gene coexpression landscapes using dictionary learning and sparse coding.
Li, Yujie; Chen, Hanbo; Jiang, Xi; Li, Xiang; Lv, Jinglei; Peng, Hanchuan; Tsien, Joe Z; Liu, Tianming
2017-12-01
Gene coexpression patterns carry rich information regarding enormously complex brain structures and functions. Characterization of these patterns in an unbiased, integrated, and anatomically comprehensive manner will illuminate the higher-order transcriptome organization and offer genetic foundations of functional circuitry. Here using dictionary learning and sparse coding, we derived coexpression networks from the space-resolved anatomical comprehensive in situ hybridization data from Allen Mouse Brain Atlas dataset. The key idea is that if two genes use the same dictionary to represent their original signals, then their gene expressions must share similar patterns, thereby considering them as "coexpressed." For each network, we have simultaneous knowledge of spatial distributions, the genes in the network and the extent a particular gene conforms to the coexpression pattern. Gene ontologies and the comparisons with published gene lists reveal biologically identified coexpression networks, some of which correspond to major cell types, biological pathways, and/or anatomical regions.
Sääf, Annika M.; Halbleib, Jennifer M.; Chen, Xin; Yuen, Siu Tsan; Leung, Suet Yi
2007-01-01
Posttranslational mechanisms are implicated in the development of epithelial cell polarity, but little is known about the patterns of gene expression and transcriptional regulation during this process. We characterized temporal patterns of gene expression during cell–cell adhesion-initiated polarization of cultured human Caco-2 cells, which develop structural and functional polarity resembling enterocytes in vivo. A distinctive switch in gene expression patterns occurred upon formation of cell–cell contacts. Comparison to gene expression patterns in normal human colon and colon tumors revealed that the pattern in proliferating, nonpolarized Caco-2 cells paralleled patterns seen in human colon cancer in vivo, including expression of genes involved in cell proliferation. The pattern switched in polarized Caco-2 cells to one more closely resembling that in normal colon tissue, indicating that regulation of transcription underlying Caco-2 cell polarization is similar to that during enterocyte differentiation in vivo. Surprisingly, the temporal program of gene expression in polarizing Caco-2 cells involved changes in signaling pathways (e.g., Wnt, Hh, BMP, FGF) in patterns similar to those during migration and differentiation of intestinal epithelial cells in vivo, despite the absence of morphogen gradients and interactions with stromal cells characteristic of enterocyte differentiation in situ. The full data set is available at http://microarray-pubs.stanford.edu/CACO2. PMID:17699589
2014-01-01
Background Sho-saiko-to (SST) (also known as so-shi-ho-tang or xiao-chai-hu-tang) has been widely prescribed for chronic liver diseases in traditional Oriental medicine. Despite the substantial amount of clinical evidence for SST, its molecular mechanism has not been clearly identified at a genome-wide level. Methods By using a microarray, we analyzed the temporal changes of messenger RNA (mRNA) and microRNA expression in primary mouse hepatocytes after SST treatment. The pattern of genes regulated by SST was identified by using time-series microarray analysis. The biological function of genes was measured by pathway analysis. For the identification of the exact targets of the microRNAs, a permutation-based correlation method was implemented in which the temporal expression of mRNAs and microRNAs were integrated. The similarity of the promoter structure between temporally regulated genes was measured by analyzing the transcription factor binding sites in the promoter region. Results The SST-regulated gene expression had two major patterns: (1) a temporally up-regulated pattern (463 genes) and (2) a temporally down-regulated pattern (177 genes). The integration of the genes and microRNA demonstrated that 155 genes could be the targets of microRNAs from the temporally up-regulated pattern and 19 genes could be the targets of microRNAs from the temporally down-regulated pattern. The temporally up-regulated pattern by SST was associated with signaling pathways such as the cell cycle pathway, whereas the temporally down-regulated pattern included drug metabolism-related pathways and immune-related pathways. All these pathways could be possibly associated with liver regenerative activity of SST. Genes targeted by microRNA were moreover associated with different biological pathways from the genes not targeted by microRNA. An analysis of promoter similarity indicated that co-expressed genes after SST treatment were clustered into subgroups, depending on the temporal expression patterns. Conclusions We are the first to identify that SST regulates temporal gene expression by way of microRNA. MicroRNA targets and non-microRNA targets moreover have different biological roles. This functional segregation by microRNA would be critical for the elucidation of the molecular activities of SST. PMID:24410935
Song, Kwang Hoon; Kim, Yun Hee; Kim, Bu-Yeo
2014-01-11
Sho-saiko-to (SST) (also known as so-shi-ho-tang or xiao-chai-hu-tang) has been widely prescribed for chronic liver diseases in traditional Oriental medicine. Despite the substantial amount of clinical evidence for SST, its molecular mechanism has not been clearly identified at a genome-wide level. By using a microarray, we analyzed the temporal changes of messenger RNA (mRNA) and microRNA expression in primary mouse hepatocytes after SST treatment. The pattern of genes regulated by SST was identified by using time-series microarray analysis. The biological function of genes was measured by pathway analysis. For the identification of the exact targets of the microRNAs, a permutation-based correlation method was implemented in which the temporal expression of mRNAs and microRNAs were integrated. The similarity of the promoter structure between temporally regulated genes was measured by analyzing the transcription factor binding sites in the promoter region. The SST-regulated gene expression had two major patterns: (1) a temporally up-regulated pattern (463 genes) and (2) a temporally down-regulated pattern (177 genes). The integration of the genes and microRNA demonstrated that 155 genes could be the targets of microRNAs from the temporally up-regulated pattern and 19 genes could be the targets of microRNAs from the temporally down-regulated pattern. The temporally up-regulated pattern by SST was associated with signaling pathways such as the cell cycle pathway, whereas the temporally down-regulated pattern included drug metabolism-related pathways and immune-related pathways. All these pathways could be possibly associated with liver regenerative activity of SST. Genes targeted by microRNA were moreover associated with different biological pathways from the genes not targeted by microRNA. An analysis of promoter similarity indicated that co-expressed genes after SST treatment were clustered into subgroups, depending on the temporal expression patterns. We are the first to identify that SST regulates temporal gene expression by way of microRNA. MicroRNA targets and non-microRNA targets moreover have different biological roles. This functional segregation by microRNA would be critical for the elucidation of the molecular activities of SST.
Ma, Meng; Wang, Qian; Li, Zhanjie; Cheng, Huihui; Li, Zhaojie; Liu, Xiangli; Song, Weining; Appels, Rudi; Zhao, Huixian
2015-07-01
Several studies have described quantitative trait loci (QTL) for seed size in wheat, but the relevant genes and molecular mechanisms remain largely unknown. Here we report the functional characterization of the wheat TaCYP78A3 gene and its effect on seed size. TaCYP78A3 encoded wheat cytochrome P450 CYP78A3, and was specifically expressed in wheat reproductive organs. TaCYP78A3 activity was positively correlated with the final seed size. Its silencing caused a reduction of cell number in the seed coat, resulting in an 11% decrease in wheat seed size, whereas TaCYP78A3 over-expression induced production of more cells in the seed coat, leading to an 11-48% increase in Arabidopsis seed size. In addition, the cell number in the final seed coat was determined by the TaCYP78A3 expression level, which affected the extent of integument cell proliferation in the developing ovule and seed. Unfortunately, TaCYP78A3 over-expression in Arabidopsis caused a reduced seed set due to an ovule developmental defect. Moreover, TaCYP78A3 over-expression affected embryo development by promoting embryo integument cell proliferation during seed development, which also ultimately affected the final seed size in Arabidopsis. In summary, our results indicated that TaCYP78A3 plays critical roles in influencing seed size by affecting the extent of integument cell proliferation. The present study provides direct evidence that TaCYP78A3 affects seed size in wheat, and contributes to an understanding of the cellular basis of the gene influencing seed development. © 2015 The Authors The Plant Journal © 2015 John Wiley & Sons Ltd.
Park, Hyungmin; Kim, Jae-Up; Park, Soojin
2012-02-21
A simple, straightforward process for fabricating multi-scale micro- and nanostructured patterns from polystyrene-block-poly(2-vinylpyridine) (PS-b-P2VP)/poly(methyl methacrylate) (PMMA) homopolymer in a preferential solvent for PS and PMMA is demonstrated. When the PS-b-P2VP/PMMA blend films were spin-coated onto a silicon wafer, PS-b-P2VP micellar arrays consisting of a PS corona and a P2VP core were formed, while the PMMA macrodomains were isolated, due to the macrophase separation caused by the incompatibility between block copolymer micelles and PMMA homopolymer during the spin-coating process. With an increase of PMMA composition, the size of PMMA macrodomains increased. Moreover, the P2VP blocks have a strong interaction with a native oxide of the surface of the silicon wafer, so that the P2VP wetting layer was first formed during spin-coating, and PS nanoclusters were observed on the PMMA macrodomains beneath. Whereas when a silicon surface was modified with a PS brush layer, the PS nanoclusters underlying PMMA domains were not formed. The multi-scale patterns prepared from copolymer micelle/homopolymer blend films are used as templates for the fabrication of gold nanoparticle arrays by incorporating the gold precursor into the P2VP chains. The combination of nanostructures prepared from block copolymer micellar arrays and macrostructures induced by incompatibility between the copolymer and the homopolymer leads to the formation of complex, multi-scale surface patterns by a simple casting process. This journal is © The Royal Society of Chemistry 2012
Patterned Polymer Coatings Increase the Efficiency of Dew Harvesting.
Al-Khayat, Omar; Hong, Jun Ki; Beck, David M; Minett, Andrew I; Neto, Chiara
2017-04-19
Micropatterned polymer surfaces, possessing both topographical and chemical characteristics, were prepared on three-dimensional copper tubes and used to capture atmospheric water. The micropatterns mimic the structure on the back of a desert beetle that condenses water from the air in a very dry environment. The patterned coatings were prepared by the dewetting of thin films of poly-4-vinylpyridine (P4VP) on top of polystyrene films (PS) films, upon solvent annealing, and consist of raised hydrophilic bumps on a hydrophobic background. The size and density distribution of the hydrophilic bumps could be tuned widely by adjusting the initial thickness of the P4VP films: the diameter of the produced bumps and their height could be varied by almost 2 orders of magnitude (1-80 μm and 40-9000 nm, respectively), and their distribution density could be varied by 5 orders of magnitude. Under low subcooling conditions (3 °C), the highest rate of water condensation was measured on the largest (80 μm diameter) hydrophilic bumps and was found to be 57% higher than that on flat hydrophobic films. These subcooling conditions are achieved spontaneously in dew formation, by passive radiative cooling of a surface exposed to the night sky. In effect, the pattern would result in a larger number of dewy nights than a flat hydrophobic surface and therefore increases water capture efficiency. Our approach is suited to fabrication on a large scale, to enable the use of the patterned coatings for water collection with no external input of energy.
Laser resist screening for iP3500/3600 replacement for advanced reticle fabrication
NASA Astrophysics Data System (ADS)
Ota, Fumiko; Kobayashi, Hideo; Higuchi, Takao; Asakawa, Keishi
2001-01-01
This paper will describe resist screening results for iP3500/3600 replacement for the advanced laser reticle fabrication, resist coating thickness optimization proposal for the next generation as well. THMR-M100 (TOK) showed the best pattern profile with sharp shoulders and almost with no footing, and a newly developed resist, a joint-work between HOYA and a resist maker, showed the best performance in adhesion to chrome. However, there was not the best selection found unfortunately by this screening, which exceeded iP3500 in linearity and iso-dense bias (IDB) that was indispensable one for the advanced laser reticle fabrication. As regards coating thickness, we selected 307.5 nm thick as a candidate for coating thickness standard for the future with considering resist resolution performance such as linearity, γp(0-80) value and undercut, in conjunction with a risk of clear pinhole defects. For more precise comparison of iso-dense bias (IDB) performance, it would be better that the examination method is standardized because of the design pattern dependence of IDB.
Colloids with high-definition surface structures
Chen, Hsien-Yeh; Rouillard, Jean-Marie; Gulari, Erdogan; Lahann, Joerg
2007-01-01
Compared with the well equipped arsenal of surface modification methods for flat surfaces, techniques that are applicable to curved, colloidal surfaces are still in their infancy. This technological gap exists because spin-coating techniques used in traditional photolithographic processes are not applicable to the curved surfaces of spherical objects. By replacing spin-coated photoresist with a vapor-deposited, photodefinable polymer coating, we have now fabricated microstructured colloids with a wide range of surface patterns, including asymmetric and chiral surface structures, that so far were typically reserved for flat substrates. This high-throughput method can yield surface-structured colloidal particles at a rate of ≈107 to 108 particles per operator per day. Equipped with spatially defined binding pockets, microstructured colloids can engage in programmable interactions, which can lead to directed self-assembly. The ability to create a wide range of colloids with both simple and complex surface patterns may contribute to the genesis of previously unknown colloidal structures and may have important technological implications in a range of different applications, including photonic and phononic materials or chemical sensors. PMID:17592149
Plasma-formed hyperthermal atomic beams for use in thin film fabrication
NASA Astrophysics Data System (ADS)
Gilson, E. P.; Cohen, S. A.; Berlinger, B.; Chan, W.
2013-10-01
Enhancing the surface mobility of adsorbents during thin-film growth processes is important for creating certain high-quality thin films. Under the auspices of a DARPA program to develop methods for supplying momentum to adsorbates during thin-film formation without using bulk heating, a hyperthermal atomic beam (HAB) was generated and directed at silicon surfaces with patterned coatings of pentacene, gold, and other surrogates for adsorbents relevant to various thin-film coatings. The HAB was created when the plasma from a helicon plasma source struck a tungsten neutralizer plate and was reflected as neutrals. Time averaged HAB fluxes 100 times greater than in previous PPPL HAB sources have been generated. The effect of the HAB on the patterned coatings was measured using atomic force microscopy (AFM). Results are presented on the flux and energy of the HAB for various system pressures, magnetic fields, and neutralizer biases. AFM measurements of the surface topology demonstrate that the HAB energy, species, and integrated flux are all important factors in altering surface mobility. This research is supported by the U.S. Defense Advanced Research Projects Agency.
Dynamin recruitment and membrane scission at the neck of a clathrin-coated pit.
Cocucci, Emanuele; Gaudin, Raphaël; Kirchhausen, Tom
2014-11-05
Dynamin, the GTPase required for clathrin-mediated endocytosis, is recruited to clathrin-coated pits in two sequential phases. The first is associated with coated pit maturation; the second, with fission of the membrane neck of a coated pit. Using gene-edited cells that express dynamin2-EGFP instead of dynamin2 and live-cell TIRF imaging with single-molecule EGFP sensitivity and high temporal resolution, we detected the arrival of dynamin at coated pits and defined dynamin dimers as the preferred assembly unit. We also used live-cell spinning-disk confocal microscopy calibrated by single-molecule EGFP detection to determine the number of dynamins recruited to the coated pits. A large fraction of budding coated pits recruit between 26 and 40 dynamins (between 1 and 1.5 helical turns of a dynamin collar) during the recruitment phase associated with neck fission; 26 are enough for coated vesicle release in cells partially depleted of dynamin by RNA interference. We discuss how these results restrict models for the mechanism of dynamin-mediated membrane scission. © 2014 Cocucci et al. This article is distributed by The American Society for Cell Biology under license from the author(s). Two months after publication it is available to the public under an Attribution–Noncommercial–Share Alike 3.0 Unported Creative Commons License (http://creativecommons.org/licenses/by-nc-sa/3.0).
Aniket; Reid, Robert; Hall, Benika; Marriott, Ian; El-Ghannam, Ahmed
2015-06-01
Pro-osteogenic stimulation of bone cells by bioactive ceramic-coated orthopedic implants is influenced by both surface roughness and material chemistry; however, their concomitant impact on osteoblast behavior is not well understood. The aim of this study is to investigate the effects of nano-scale roughness and chemistry of bioactive silica-calcium phosphate nanocomposite (SCPC50) coated Ti-6Al-4V on modulating early bone cell responses. Cell attachment was higher on SCPC50-coated substrates compared to the uncoated controls; however, cells on the uncoated substrate exhibited greater spreading and superior quality of F-actin filaments than cells on the SCPC50-coated substrates. The poor F-actin filament organization on SCPC50-coated substrates is thought to be due to the enhanced calcium uptake by the ceramic surface. Dissolution analyses showed that an increase in surface roughness was accompanied by increased calcium uptake, and increased phosphorous and silicon release, all of which appear to interfere with F-actin assembly and osteoblast morphology. Moreover, cell attachment onto the SCPC50-coated substrates correlated with the known adsorption of fibronectin, and was independent of surface roughness. High-throughput genome sequencing showed enhanced expression of extracellular matrix and cell differentiation related genes. These results demonstrate a synergistic relationship between bioactive ceramic coating roughness and material chemistry resulting in a phenotype that leads to early osteoblast differentiation. © 2014 Wiley Periodicals, Inc.
Kappen, Claudia
2016-01-01
The process of patterning along the anterior-posterior axis in vertebrates is highly conserved. The function of Hox genes in the axis patterning process is particularly well documented for bone development in the vertebral column and the limbs. We here show that Hoxb6, in skeletal elements at the cervico-thoracic junction, controls multiple independent aspects of skeletal pattern, implicating discrete developmental pathways as substrates for this transcription factor. In addition, we demonstrate that Hoxb6 function is subject to modulation by genetic factors. These results establish Hox-controlled skeletal pattern as a quantitative trait modulated by gene-gene interactions, and provide evidence that distinct modifiers influence the function of conserved developmental genes in fundamental patterning processes. PMID:26800342
Long-term erosion of plasma-facing materials with different surface roughness in ASDEX Upgrade
NASA Astrophysics Data System (ADS)
Hakola, A.; Karhunen, J.; Koivuranta, S.; Likonen, J.; Balden, M.; Herrmann, A.; Mayer, M.; Müller, H. W.; Neu, R.; Rohde, V.; Sugiyama, K.; The ASDEX Upgrade Team
2014-04-01
The effect of surface roughness on the long-term erosion patterns of tungsten coatings was investigated in the outer strike-point region of ASDEX Upgrade during its 2010-11 plasma operations. The net erosion rates of rough coatings (Ra = 5-6 μm) were three to seven times smaller than those of smooth coatings (Ra = 0.4-0.8 μm). This is because rough surfaces are largely modified and damaged in the microscopic scale but the material is re-deposited together with boron, deuterium and carbon on the shadowed sides of the most prominent surface features. In addition, we observed that W coatings were eroded on average at a rate of 0.03 nm s-1, which was three to four times smaller than the value for Cr, simulating here steel.
A structural view of egg coat architecture and function in fertilization.
Monné, Magnus; Jovine, Luca
2011-10-01
Species-restricted interaction between gametes at the beginning of fertilization is mediated by the extracellular coat of the egg, a matrix of cross-linked glycoprotein filaments called the zona pellucida (ZP) in mammals and the vitelline envelope in nonmammals. All egg coat subunits contain a conserved protein-protein interaction module-the "ZP domain"-that allows them to polymerize upon dissociation of a C-terminal propeptide containing an external hydrophobic patch (EHP). Recently, the first crystal structures of a ZP domain protein, sperm receptor ZP subunit zona pellucida glycoprotein 3 (ZP3), have been reported, giving a glimpse of the structural organization of the ZP at the atomic level and the molecular basis of gamete recognition in vertebrates. The ZP module is divided in two related immunoglobulin-like domains, ZP-N and ZP-C, that contain characteristic disulfide bond patterns and, in the case of ZP-C, also incorporate the EHP. This segment lies at the interface between the two domains, which are connected by a long loop carrying a conserved O-glycan important for binding to sperm in vitro. The structures explain several apparently contradictory observations by reconciling the variable disulfide bond patterns found in different homologues of ZP3 as well as the multiple ZP3 determinants alternatively involved in gamete interaction. These findings have implications for our understanding of ZP subunit biogenesis; egg coat assembly, architecture, and interaction with sperm; structural rearrangements leading to postfertilization hardening of the ZP and the block to sperm binding; and the evolutionary origin of egg coats.
Desmoglein 4 diversity and correlation analysis with coat color in goat.
E, G X; Zhao, Y J; Ma, Y H; Cao, G L; He, J N; Na, R S; Zhao, Z Q; Jiang, C D; Zhang, J H; Arlvd, S; Chen, L P; Qiu, X Y; Hu, W; Huang, Y F
2016-03-04
Desmoglein 4 (DSG4) has an important role in the development of wool traits in domestic animals. The full-length DSG4 gene, which contains 3918 bp, a complete open-reading-frame, and encodes a 1040-amino acid protein, was amplified from Liaoning cashmere goat. The sequence was compared with that of DSG4 from other animals and the results show that the DSG4 coding region is consistent with interspecies conservation. Thirteen single-nucleotide polymorphisms (SNPs) were identified in a highly variable region of DSG4, and one SNP (M-1, G>T) was significantly correlated with white and black coat color in goat. Haplotype distribution of the highly variable region of DSG4 was assessed in 179 individuals from seven goat breeds to investigate its association with coat color and its differentiation among populations. However, the lack of a signature result indicates DGS4 haplotypes related with the color of goat coat.
2012-01-01
Background Body coloration is an ecologically important trait that is often involved in prey-predator interactions through mimicry and crypsis. Although this subject has attracted the interest of biologists and the general public, our scientific knowledge on the subject remains fragmentary. In the caterpillar of the swallowtail butterfly Papilio xuthus, spectacular changes in the color pattern are observed; the insect mimics bird droppings (mimetic pattern) as a young larva, and switches to a green camouflage coloration (cryptic pattern) in the final instar. Despite the wide variety and significance of larval color patterns, few studies have been conducted at a molecular level compared with the number of studies on adult butterfly wing patterns. Results To obtain a catalog of genes involved in larval mimetic and cryptic pattern formation, we constructed expressed sequence tag (EST) libraries of larval epidermis for P. xuthus, and P. polytes that contained 20,736 and 5,376 clones, respectively, representing one of the largest collections available in butterflies. A comparison with silkworm epidermal EST information revealed the high expression of putative blue and yellow pigment-binding proteins in Papilio species. We also designed a microarray from the EST dataset information, analyzed more than five stages each for six markings, and confirmed spatial expression patterns by whole-mount in situ hybridization. Hence, we succeeded in elucidating many novel marking-specific genes for mimetic and cryptic pattern formation, including pigment-binding protein genes, the melanin-associated gene yellow-h3, the ecdysteroid synthesis enzyme gene 3-dehydroecdysone 3b-reductase, and Papilio-specific genes. We also found many cuticular protein genes with marking specificity that may be associated with the unique surface nanostructure of the markings. Furthermore, we identified two transcription factors, spalt and ecdysteroid signal-related E75, as genes expressed in larval eyespot markings. This finding suggests that E75 is a strong candidate mediator of the hormone-dependent coordination of larval pattern formation. Conclusions This study is one of the most comprehensive molecular analyses of complicated morphological features, and it will serve as a new resource for studying insect mimetic and cryptic pattern formation in general. The wide variety of marking-associated genes (both regulatory and structural genes) identified by our screening indicates that a similar strategy will be effective for understanding other complex traits. PMID:22651552
Kumar, Amit; Wonganan, Piyanuch; Sandoval, Michael A.; Li, Xinran; Zhu, Saijie; Cui, Zhengrong
2012-01-01
Previously, it was shown that microneedle-mediated transcutaneous immunization with plasmid DNA can potentially induce a stronger immune response than intramuscular injection of the same plasmid DNA. In the present study, we showed that the immune responses induced by transcutaneous immunization by applying plasmid DNA onto a skin area pretreated with solid microneedles were significantly enhanced by coating the plasmid DNA on the surface of cationic nanoparticles. In addition, the net surface charge of the DNA-coated nanoparticles significantly affected their in vitro skin permeation and their ability to induce immune responses in vivo. Transcutaneous immunization with plasmid DNA-coated net positively charged anoparticles elicited a stronger immune response than with plasmid DNA-coated net negatively charged nanoparticles or by intramuscular immunization with plasmid DNA alone. Transcutaneous immunization with plasmid DNA-coated net positively charged nanoparticles induced comparable immune responses as intramuscular injection of them, but transcutaneous immunization was able to induce specific mucosal immunity and a more balanced T helper type 1 and type 2 response. The ability of the net positively charged DNA-coated nanoparticles to induce a strong immune response through microneedle-mediated transcutaneous immunization may be attributed to their ability to increase the expression of the antigen gene encoded by the plasmid and to more effectively stimulate the maturation of antigen-presenting cells. PMID:22921518
Ding, Ding; Xie, Youtao; Li, Kai; Huang, Liping; Zheng, Xuebin
2018-01-01
Recently, tantalum has been attracting much attention for its anticorrosion resistance and biocompatibility, and it has been widely used in surface modification for implant applications. To improve its osteogenic differentiation of human bone marrow stem cells (hBMSCs), a micro/nano structure has been fabricated on the tantalum coating surface through the combination of anodic oxidation and plasma spraying method. The morphology, composition, and microstructure of the modified coating were comprehensively studied by employing scanning electron microscopy (SEM), X-ray diffraction (XRD) as well as transmission electron microscopy (TEM). The effects of hierarchical structures as well as micro-porous structure of tantalum coating on the behavior for human bone marrow stem cells (hBMSCs) were evaluated and compared at both cellular and molecular levels in vitro. The experimental results show that a hierarchical micro/nano structure with Ta2O5 nanotubes spread onto a micro-scale tantalum coating has been fabricated successfully, which is confirmed to promote cell adhesion and spreading. Besides, the hierarchical micro/nano tantalum coating can provide 1.5~2.1 times improvement in gene expression, compared with the micro-porous tantalum coating. It demonstrates that it can effectively enhance the proliferation and differentiation of hBMSCs in vitro. PMID:29614022
Ding, Ding; Xie, Youtao; Li, Kai; Huang, Liping; Zheng, Xuebin
2018-04-03
Recently, tantalum has been attracting much attention for its anticorrosion resistance and biocompatibility, and it has been widely used in surface modification for implant applications. To improve its osteogenic differentiation of human bone marrow stem cells (hBMSCs), a micro/nano structure has been fabricated on the tantalum coating surface through the combination of anodic oxidation and plasma spraying method. The morphology, composition, and microstructure of the modified coating were comprehensively studied by employing scanning electron microscopy (SEM), X-ray diffraction (XRD) as well as transmission electron microscopy (TEM). The effects of hierarchical structures as well as micro-porous structure of tantalum coating on the behavior for human bone marrow stem cells (hBMSCs) were evaluated and compared at both cellular and molecular levels in vitro. The experimental results show that a hierarchical micro/nano structure with Ta₂O₅ nanotubes spread onto a micro-scale tantalum coating has been fabricated successfully, which is confirmed to promote cell adhesion and spreading. Besides, the hierarchical micro/nano tantalum coating can provide 1.5~2.1 times improvement in gene expression, compared with the micro-porous tantalum coating. It demonstrates that it can effectively enhance the proliferation and differentiation of hBMSCs in vitro.
Lin, Hsin-Yi; Chang, Tsang-Wen; Peng, Tie-Kun
2018-06-01
Alginate hydrogel fibers embedded with bone cells and diclofenac were coated with a layer of chitosan hydrogel and made into a porous scaffold by three-dimensional (3D) printing for drug release and bone regeneration. It was hypothesized that the chitosan coating could improve the scaffold's drug retention and release properties and biocompatibility. Macrophage cells were stimulated and cocultured with the scaffold. Tests were conducted to show how the chitosan coating affected the scaffold's drug release efficacy and how the release efficacy affected the cellular activities of stimulated macrophages and bone cells. The bone cells encapsulated in the coated scaffold demonstrated good viability after the acidic/basic coating process. The coating improved the retention and release efficacy of diclofenac and hence significantly inhibited interleukin-6 and tumor necrosis factor-α secretion from macrophages (p < 0.05). The bone cells in the coated sample mineralized more extensively than the control (p < 0.01). They also more actively expressed genes that produce proteins for extracellular matrix remodeling, MMP13, and interacting with the mineral matrix, OPN (both p < 0.01). It is believed that on days 7 and 10, when diclofenac was depleted and the concentrations of inflammatory compounds surged, the coating effectively blocked the harmful compounds and protected the bone cells within the fibers. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 106A: 1511-1521, 2018. © 2018 Wiley Periodicals, Inc.
Refractory amorphous metallic (W/0.6/ Re/0.4/)76B24 coatings on steel substrates
NASA Technical Reports Server (NTRS)
Thakoor, A. P.; Lamb, J. L.; Khanna, S. K.; Mehra, M.; Johnson, W. L.
1985-01-01
Refractory metallic coatings of (W/0.6/ Re/0.4/)76B24 (WReB) have been deposited onto glass, quartz, and heat-treated AISI 52100 bearing steel substrates by dc magnetron sputtering. As-deposited WReB films are amorphous, as shown by their diffuse X-ray diffraction patterns; chemically homogeneous, according to secondary ion mass spectrometry (SIMS) analysis; and they exhibit a very high (approximately 1000 C) crystallization temperature. Adhesion strength of these coatings on heat-treated AISI 52100 steel is in excess of approximately 20,000 psi and they possess high microhardness (approximately 2400 HV50). Unlubricated wear resistance of such hard and adherent amorphous metallic coatings on AISI 52100 steel is studied using the pin-on-disc method under various loading conditions. Amorphous metallic WReB coatings, about 4 microns thick, exhibit an improvement of more than two and a half orders of magnitude in the unlubricated wear resistance over that of the uncoated AISI 52100 steel.
NASA Astrophysics Data System (ADS)
Pyo, Youngjun; Choi, Dahyun; Son, Yeon-Ho; Kang, Suhee; Yoon, Eric H.; Jung, Seung-Boo; Kim, Yongil; Sunyong Lee, Caroline
2016-05-01
A novel method of carbonaceous coating on the surface of copper particles was developed through a chemical vapor deposition (CVD) process to prevent the oxidation of copper nanoparticles (CNPs). The types of poly(vinyl pyrrolidone) (PVP) used were K-12 (M W 3,500) and K-30 (M W 45,000). The amounts of PVP used ranged from 10 to 50 wt %. Additionally, processing temperatures of 900 and 875 °C were tested and compared. The optimum CVD process conditions for the carbonaceous coating were as follows: 875 °C processing temperature, 50 wt % K12 PVP solution, and gas conditions of \\text{Ar}:\\text{H}2 = 1:1. The resistivity change in the fabricated copper pattern was confirmed that the initial resistivity value of the ink with a mixing ratio of carbonaceous-coated CNPs to 1-octanethiol-coated CNPs of 4:6 (w/w) maintained its initial resistivity value of 2.93 × 10-7 Ω·m for more than 210 days.
Nanopillar Photonic Crystal Lasers for Tb/s Transceivers on Silicon
2015-07-09
dimensions of NWs can be adjusted by lithographically patterned nanoholes on dielectric mask. Some studies of SAE growth on Si using Ga droplets, i.e. Ga...inside the patterned nanoholes . In this study, the effects of seeding layer growth temperature on uniformity, vertical yield, and optical...thermal silicon dioxide (SiO2). Next, E-Beam resist ZEP520A was coated and nanoholes were patterned by E-Beam lithography (EBL). The designed diameter
Photo-Definable Self Assembled Maerials
DOSHI, DHAVAL; [et al
2004-10-26
The present invention provides a mesoporous material comprising at least one region of mesoporous material patterned at a lithographic scale. The present invention also provides a a method for forming a patterned mesoporous material comprising: coating a sol on a substrate to form a film, the sol comprising: a templating molecule, a photoactivator generator, a material capable of being sol-gel processed, water, and a solvent; and exposing the film to light to form a patterned mesoporous material.
Surface Functionalization of Orthopedic Titanium Implants with Bone Sialoprotein
Ritz, Ulrike; Ackermann, Angelika; Anthonissen, Joris; Kaufmann, Kerstin B.; Brendel, Christian; Götz, Hermann; Rommens, Pol M.; Hofmann, Alexander
2016-01-01
Orthopedic implant failure due to aseptic loosening and mechanical instability remains a major problem in total joint replacement. Improving osseointegration at the bone-implant interface may reduce micromotion and loosening. Bone sialoprotein (BSP) has been shown to enhance bone formation when coated onto titanium femoral implants and in rat calvarial defect models. However, the most appropriate method of BSP coating, the necessary level of BSP coating, and the effect of BSP coating on cell behavior remain largely unknown. In this study, BSP was covalently coupled to titanium surfaces via an aminosilane linker (APTES), and its properties were compared to BSP applied to titanium via physisorption and untreated titanium. Cell functions were examined using primary human osteoblasts (hOBs) and L929 mouse fibroblasts. Gene expression of specific bone turnover markers at the RNA level was detected at different intervals. Cell adhesion to titanium surfaces treated with BSP via physisorption was not significantly different from that of untreated titanium at any time point, whereas BSP application via covalent coupling caused reduced cell adhesion during the first few hours in culture. Cell migration was increased on titanium disks that were treated with higher concentrations of BSP solution, independent of the coating method. During the early phases of hOB proliferation, a suppressive effect of BSP was observed independent of its concentration, particularly when BSP was applied to the titanium surface via physisorption. Although alkaline phosphatase activity was reduced in the BSP-coated titanium groups after 4 days in culture, increased calcium deposition was observed after 21 days. In particular, the gene expression level of RUNX2 was upregulated by BSP. The increase in calcium deposition and the stimulation of cell differentiation induced by BSP highlight its potential as a surface modifier that could enhance the osseointegration of orthopedic implants. Both physisorption and covalent coupling of BSP are similarly effective, feasible methods, although a higher BSP concentration is recommended. PMID:27111551
Kaufman, Gili; Whitescarver, Ryan A; Nunes, Laiz; Palmer, Xavier-Lewis; Skrtic, Drago; Tutak, Wojtek
2018-01-24
Deep wounds in the gingiva caused by trauma or surgery require a rapid and robust healing of connective tissues. We propose utilizing gas-brushed nanofibers coated with collagen and fibrin for that purpose. Our hypotheses are that protein-coated nanofibers will: (i) attract and mobilize cells in various spatial orientations, and (ii) regulate the expression levels of specific extracellular matrix (ECM)-associated proteins, determining the initial conformational nature of dense and soft connective tissues. Gingival fibroblast monolayers and 3D spheroids were cultured on ECM substrate and covered with gas-blown poly-(DL-lactide-co-glycolide) (PLGA) nanofibers (uncoated/coated with collagen and fibrin). Cell attraction and rearrangement was followed by F-actin staining and confocal microscopy. Thicknesses of the cell layers, developed within the nanofibers, were quantified by ImageJ software. The expression of collagen1α1 chain (Col1α1), fibronectin, and metalloproteinase 2 (MMP2) encoding genes was determined by quantitative reverse transcription analysis. Collagen- and fibrin- coated nanofibers induced cell migration toward fibers and supported cellular growth within the scaffolds. Both proteins affected the spatial rearrangement of fibroblasts by favoring packed cell clusters or intermittent cell spreading. These cell arrangements resembled the structural characteristic of dense and soft connective tissues, respectively. Within three days of incubation, fibroblast spheroids interacted with the fibers, and grew robustly by increasing their thickness compared to monolayers. While the ECM key components, such as fibronectin and MMP2 encoding genes, were expressed in both protein groups, Col1α1 was predominantly expressed in bundled fibroblasts grown on collagen fibers. This enhanced expression of collagen1 is typical for dense connective tissue. Based on results of this study, our gas-blown, collagen- and fibrin-coated PLGA nanofibers are viable candidates for engineering soft and dense connective tissues with the required structural characteristics and functions needed for wound healing applications. Rapid regeneration of these layers should enhance healing of open wounds in a harsh oral environment.
Ritz, U; Nusselt, T; Sewing, A; Ziebart, T; Kaufmann, K; Baranowski, A; Rommens, P M; Hofmann, Alexander
2017-01-01
Targeted modifications of the bulk implant surfaces using bioactive agents provide a promising tool for improvement of the long-term bony and soft tissue integration of dental implants. In this study, we assessed the cellular responses of primary human gingival fibroblasts (HGF) to different surface modifications of titanium (Ti) and titanium nitride (TiN) alloys with type I collagen or cyclic-RGDfK-peptide in order to define a modification improving long-term implants in dental medicine. Employing Ti and TiN implants, we compared the performance of simple dip coating and anodic immobilization of type I collagen that provided collagen layers of two different thicknesses. HGF were seeded on the different coated implants, and adhesion, proliferation, and gene expression were analyzed. Although there were no strong differences in initial cell adhesion between the groups at 2 and 4 hours, we found that all surface modifications induced higher proliferation rates as compared to the unmodified controls. Consistently, gene expression levels of cell adhesion markers (focal adhesion kinase (FAK), integrin beta1, and vinculin), cell differentiation markers (FGFR1, TGFb-R1), extracellular protein markers (type I collagen, vimentin), and cytoskeletal protein marker aktinin-1 were consistently higher in all surface modification groups at two different time points of investigation as compared to the unmodified controls. Our results indicate that simple dip coating of Ti and TiN with collagen is sufficient to induce in vitro cellular responses that are comparable to those of more reliable coating methods like anodic adsorption, chemical cross-linking, or RGD coating. TiN alloys do not possess any positive or adverse effects on HGF. Our results demonstrate a simple, yet effective, method for collagen coating on titanium implants to improve the long term integration and stability of dental implants.
The detection of organic solvent vapor by using polymer coated chemocapacitor sensor
NASA Astrophysics Data System (ADS)
Rusdiarna Indrapraja, Apik; Rivai, Muhammad; Arifin, Achmad; Purwanto, Djoko
2017-05-01
A chemocapacitor consists of planar interdigital electrodes (IDE) made by two comb electrodes on a substrate. A dielectric film was applied on the electrodes in which the absorbed vapor will modify its permittivity. This study has fabricated chemocapacitor with the IDE distance of 0.5 mm, while the dielectric film was a sensitive layer consisting of a polymeric material. The deposition of the polymeric film was accomplished by drop casting. A sensor array consisting of four chemocapacitors coated with different polymers namely PEG-1540, PEG-20M, PEG-6000, and PVP was used to obtain the pattern of shift in the capacitance. The integrated circuit AD7746 was used as the capacitance to-digital converter (CDC). The organic solvents of ethanol, benzene, and aceton were used as the vapor samples in this experiment. The results showed that the change in the capacitance value increases proportionally to the concentration of vapour where sensors coated with PEG-1540 and PVP have higher sensitivity, i.e. 0.0028pF/part per thousand and 0.0027pF/part per thousand, respectively. Based on the capacitance to digital conversion capabilities, the system provides there solution of 0.4084ppm. The sensor array could produce a different pattern for each of the vapor sample. The Neural Network pattern recognition system could identify the type of vapor automatically with the root mean square error of 10-5
NASA Technical Reports Server (NTRS)
Weitzel, A. J.; Wyatt, S. E.; Parsons-Wingerter, P.
2016-01-01
Venation patterning in leaves is a major determinant of photosynthesis efficiency because of its dependency on vascular transport of photo-assimilates, water, and minerals. Arabidopsis thaliana grown in microgravity show delayed growth and leaf maturation. Gene expression data from the roots, hypocotyl, and leaves of A. thaliana grown during spaceflight vs. ground control analyzed by Affymetrix microarray are available through NASA's GeneLab (GLDS-7). We analyzed the data for differential expression of genes in leaves resulting from the effects of spaceflight on vascular patterning. Two genes were found by preliminary analysis to be up-regulated during spaceflight that may be related to vascular formation. The genes are responsible for coding an ARGOS (Auxin-Regulated Gene Involved in Organ Size)-like protein (potentially affecting cell elongation in the leaves), and an F-box/kelch-repeat protein (possibly contributing to protoxylem specification). Further analysis that will focus on raw data quality assessment and a moderated t-test may further confirm up-regulation of the two genes and/or identify other gene candidates. Plants defective in these genes will then be assessed for phenotype by the mapping and quantification of leaf vascular patterning by NASA's VESsel GENeration (VESGEN) software to model specific vascular differences of plants grown in spaceflight.
Klas, Ferdinand E; Fuchs, Marc; Gonsalves, Dennis
2006-10-01
The spatial and temporal patterns of aphid-vectored spread of Zucchini Yellow Mosaic Virus (ZYMV) and Watermelon Mosaic Virus (WMV) were monitored over two consecutive years in plantings of nontransgenic and transgenic squash ZW-20H (commercial cv. Freedom II) and ZW-20B, both expressing the coat protein genes of ZYMV and WMV. All test plants were surrounded by nontransgenic plants that were mechanically inoculated with ZYMV or WMV, and served as primary virus source. Across all trials, none of the transgenic plants exhibited systemic symptoms upon infection by ZYMV and WMV but a few of them developed localized chlorotic dots and/or blotches, and had low mixed infection rates [4% (6 of 139) of ZW-20H and 9% (13 of 139) of ZW-20B], as shown by ELISA. Geostatistical analysis of ELISA positive transgenic plants indicated, (i) a lack of spatial relationship on spread of ZYMV and WMV for ZW-20H with flat omnidirectional experimental semivariograms that fitted poorly theoretical models, and (ii) some extent of spatial dependence on ZYMV spread for ZW-20B with a well structured experimental semivariogram that fitted poorly theoretical models during the first but not the second growing season. In contrast, a strong spatial dependence on spread of ZYMV and WMV was found for nontransgenic plants, which developed severe systemic symptoms, had prevalent mixed infection rates (62%, 86 of 139), and well-defined omnidirectional experimental semivariograms that fitted a spherical model. Geostatistical data were sustained by virus transmission experiments with Myzus persicae in screenhouses, showing that commercial transgenic squash ZW-20H alter the dynamics of ZYMV and WMV epidemics by preventing secondary plant-to-plant spread.
In Vitro and In Vivo Evaluation of Zinc-Modified Ca–Si-Based Ceramic Coating for Bone Implants
Zheng, Xuebin; He, Dannong; Ye, Xiaojian; Wang, Meiyan
2013-01-01
The host response to calcium silicate ceramic coatings is not always favorable because of their high dissolution rates, leading to high pH within the surrounding physiological environment. Recently, a zinc-incorporated calcium silicate-based ceramic Ca2ZnSi2O7 coating, developed on a Ti-6Al-4V substrate using plasma-spray technology, was found to exhibit improved chemical stability and biocompatibility. This study aimed to investigate and compare the in vitro response of osteoblastic MC3T3-E1 cells cultured on Ca2ZnSi2O7 coating, CaSiO3 coating, and uncoated Ti-6Al-4V titanium control at cellular and molecular level. Our results showed Ca2ZnSi2O7 coating enhanced MC3T3-E1 cell attachment, proliferation, and differentiation compared to CaSiO3 coating and control. In addition, Ca2ZnSi2O7 coating increased mRNA levels of osteoblast-related genes (alkaline phosphatase, procollagen α1(I), osteocalcin), insulin-like growth factor-I (IGF-I), and transforming growth factor-β1 (TGF-β1). The in vivo osteoconductive properties of Ca2ZnSi2O7 coating, compared to CaSiO3 coating and control, was investigated using a rabbit femur defect model. Histological and histomorphometrical analysis demonstrated new bone formation in direct contact with the Ca2ZnSi2O7 coating surface in absence of fibrous tissue and higher bone-implant contact rate (BIC) in the Ca2ZnSi2O7 coating group, indicating better biocompatibility and faster osseointegration than CaSiO3 coated and control implants. These results indicate Ca2ZnSi2O7 coated implants have applications in bone tissue regeneration, since they are biocompatible and able to osseointegrate with host bone. PMID:23483914
In vitro and in vivo evaluation of zinc-modified ca-si-based ceramic coating for bone implants.
Yu, Jiangming; Li, Kai; Zheng, Xuebin; He, Dannong; Ye, Xiaojian; Wang, Meiyan
2013-01-01
The host response to calcium silicate ceramic coatings is not always favorable because of their high dissolution rates, leading to high pH within the surrounding physiological environment. Recently, a zinc-incorporated calcium silicate-based ceramic Ca2ZnSi2O7 coating, developed on a Ti-6Al-4V substrate using plasma-spray technology, was found to exhibit improved chemical stability and biocompatibility. This study aimed to investigate and compare the in vitro response of osteoblastic MC3T3-E1 cells cultured on Ca2ZnSi2O7 coating, CaSiO3 coating, and uncoated Ti-6Al-4V titanium control at cellular and molecular level. Our results showed Ca2ZnSi2O7 coating enhanced MC3T3-E1 cell attachment, proliferation, and differentiation compared to CaSiO3 coating and control. In addition, Ca2ZnSi2O7 coating increased mRNA levels of osteoblast-related genes (alkaline phosphatase, procollagen α1(I), osteocalcin), insulin-like growth factor-I (IGF-I), and transforming growth factor-β1 (TGF-β1). The in vivo osteoconductive properties of Ca2ZnSi2O7 coating, compared to CaSiO3 coating and control, was investigated using a rabbit femur defect model. Histological and histomorphometrical analysis demonstrated new bone formation in direct contact with the Ca2ZnSi2O7 coating surface in absence of fibrous tissue and higher bone-implant contact rate (BIC) in the Ca2ZnSi2O7 coating group, indicating better biocompatibility and faster osseointegration than CaSiO3 coated and control implants. These results indicate Ca2ZnSi2O7 coated implants have applications in bone tissue regeneration, since they are biocompatible and able to osseointegrate with host bone.
ROKU: a novel method for identification of tissue-specific genes.
Kadota, Koji; Ye, Jiazhen; Nakai, Yuji; Terada, Tohru; Shimizu, Kentaro
2006-06-12
One of the important goals of microarray research is the identification of genes whose expression is considerably higher or lower in some tissues than in others. We would like to have ways of identifying such tissue-specific genes. We describe a method, ROKU, which selects tissue-specific patterns from gene expression data for many tissues and thousands of genes. ROKU ranks genes according to their overall tissue specificity using Shannon entropy and detects tissues specific to each gene if any exist using an outlier detection method. We evaluated the capacity for the detection of various specific expression patterns using synthetic and real data. We observed that ROKU was superior to a conventional entropy-based method in its ability to rank genes according to overall tissue specificity and to detect genes whose expression pattern are specific only to objective tissues. ROKU is useful for the detection of various tissue-specific expression patterns. The framework is also directly applicable to the selection of diagnostic markers for molecular classification of multiple classes.
A Bacillus subtilis Secreted Protein with a Role in Endospore Coat Assembly and Function
Serrano, Mónica; Zilhão, Rita; Ricca, Ezio; Ozin, Amanda J.; Moran, Charles P.; Henriques, Adriano O.
1999-01-01
Bacterial endospores are encased in a complex protein coat, which confers protection against noxious chemicals and influences the germination response. In Bacillus subtilis, over 20 polypeptides are organized into an amorphous undercoat, a lamellar lightly staining inner structure, and an electron-dense outer coat. Here we report on the identification of a polypeptide of about 30 kDa required for proper coat assembly, which was extracted from spores of a gerE mutant. The N-terminal sequence of this polypeptide matched the deduced product of the tasA gene, after removal of a putative 27-residue signal peptide, and TasA was immunologically detected in material extracted from purified spores. Remarkably, deletion of tasA results in the production of asymmetric spores that accumulate misassembled material in one pole and have a greatly expanded undercoat and an altered outer coat structure. Moreover, we found that tasA and gerE mutations act synergistically to decrease the efficiency of spore germination. We show that tasA is the most distal member of a three-gene operon, which also encodes the type I signal peptidase SipW. Expression of the tasA operon is enhanced 2 h after the onset of sporulation, under the control of ςH. When tasA transcription is uncoupled from sipW expression, a presumptive TasA precursor accumulates, suggesting that its maturation depends on SipW. Mature TasA is found in supernatants of sporulating cultures and intracellularly from 2 h of sporulation onward. We suggest that, at an early stage of sporulation, TasA is secreted to the septal compartment. Later, after engulfment of the prespore by the mother cell, TasA acts from the septal-proximal pole of the spore membranes to nucleate the organization of the undercoat region. TasA is the first example of a polypeptide involved in coat assembly whose production is not mother cell specific but rather precedes its formation. Our results implicate secretion as a mechanism to target individual proteins to specific cellular locations during the assembly of the bacterial endospore coat. PMID:10368135
Pottorff, Marti; Roberts, Philip A; Close, Timothy J; Lonardi, Stefano; Wanamaker, Steve; Ehlers, Jeffrey D
2014-05-01
Heat-induced browning (Hbs) of seed coats is caused by high temperatures which discolors the seed coats of many legumes, affecting the visual appearance and quality of seeds. The genetic determinants underlying Hbs in cowpea are unknown. We identified three QTL associated with the heat-induced browning of seed coats trait, Hbs-1, Hbs-2 and Hbs-3, using cowpea RIL populations IT93K-503-1 (Hbs positive) x CB46 (hbs negative) and IT84S-2246 (Hbs positive) x TVu14676 (hbs negative). Hbs-1 was identified in both populations, accounting for 28.3% -77.3% of the phenotypic variation. SNP markers 1_0032 and 1_1128 co-segregated with the trait. Within the syntenic regions of Hbs-1 in soybean, Medicago and common bean, several ethylene forming enzymes, ethylene responsive element binding factors and an ACC oxidase 2 were observed. Hbs-1 was identified in a BAC clone in contig 217 of the cowpea physical map, where ethylene forming enzymes were present. Hbs-2 was identified in the IT93K-503-1 x CB46 population and accounted for of 9.5 to 12.3% of the phenotypic variance. Hbs-3 was identified in the IT84S-2246 x TVu14676 population and accounted for 6.2 to 6.8% of the phenotypic variance. SNP marker 1_0640 co-segregated with the heat-induced browning phenotype. Hbs-3 was positioned on BAC clones in contig512 of the cowpea physical map, where several ACC synthase 1 genes were present. The identification of loci determining heat-induced browning of seed coats and co-segregating molecular markers will enable transfer of hbs alleles into cowpea varieties, contributing to higher quality seeds.
A novel MLPH variant in dogs with coat colour dilution.
Bauer, A; Kehl, A; Jagannathan, V; Leeb, T
2018-02-01
Coat colour dilution may be the result of altered melanosome transport in melanocytes. Loss-of-function variants in the melanophilin gene (MLPH) cause a recessively inherited form of coat colour dilution in many mammalian and avian species including the dog. MLPH corresponds to the D locus in many domestic animals, and recessive alleles at this locus are frequently denoted with d. In this study, we investigated dilute coloured Chow Chows whose coat colour could not be explained by their genotype at the previously known MLPH:c.-22G>A variant. Whole genome sequencing of such a dilute Chow Chow revealed another variant in the MLPH gene: MLPH:c.705G>C. We propose to designate the corresponding mutant alleles at these two variants d 1 and d 2 . We performed an association study in a cohort of 15 dilute and 28 non-dilute Chow Chows. The dilute dogs were all either compound heterozygous d 1 /d 2 or homozygous d 2 /d 2 , whereas the non-dilute dogs carried at least one wildtype allele D. The d 2 allele did not occur in 417 dogs from diverse other breeds. However, when we genotyped a Sloughi family, in which a dilute coloured puppy had been born out of non-dilute parents, we again observed perfect co-segregation of the newly discovered d 2 allele with coat colour dilution. Finally, we identified a blue Thai Ridgeback with the d 1 /d 2 genotype. Thus, our data identify the MLPH:c.705G>C as a variant explaining a second canine dilution allele. Although relatively rare overall, this d 2 allele is segregating in at least three dog breeds, Chow Chows, Sloughis and Thai Ridgebacks. © 2018 Stichting International Foundation for Animal Genetics.
Silver Nanowire Exposure Results in Internalization and Toxicity to Daphnia Magna
Scanlan, Leona D.; Reed, Robert B.; Loguinov, Alexandre V.; Antczak, Philipp; Tagmount, Abderrahmane; Aloni, Shaul; Nowinski, Daniel Thomas; Luong, Pauline; Tran, Christine; Karunaratne, Nadeeka; Pham, Don; Lin, Xin Xin; Falciani, Francesco; Higgins, Chris P.; Ranville, James F.; Vulpe, Chris D.; Gilbert, Benjamin
2013-01-01
Nanowires (NWs), high-aspect-ratio nanomaterials, are increasingly used in technological materials and consumer products and may have toxicological characteristics distinct from nanoparticles. We carried out a comprehensive evaluation of the physico-chemical stability of four silver nanowires (AgNWs) of two sizes and coatings and their toxicity to Daphnia magna. Inorganic aluminum-doped silica coatings were less effective than organic poly(vinyl pyrrolidone) coatings at preventing silver oxidation or Ag+ release and underwent a significant morphological transformation within one-hour following addition to low ionic strength Daphnia growth media. All AgNWs were highly toxic to D. magna but less toxic than ionic silver. Toxicity varied as a function of AgNW dimension, coating and solution chemistry. Ag+ release in the media could not account for observed AgNW toxicity. Single-particle inductively coupled plasma mass spectrometry (spICPMS) distinguished and quantified dissolved and nanoparticulate silver in microliter-scale volumes of Daphnia magna hemolymph with a limit of detection of approximately 10 ppb. The silver levels within the hemolymph of Daphnia exposed to both Ag+ and AgNW met or exceeded the initial concentration in the growth medium, indicating effective accumulation during filter feeding. Silver-rich particles were the predominant form of silver in hemolymph following exposure to both AgNWs and Ag+. Scanning electron microscopy (SEM) imaging of dried hemolymph found both AgNWs and silver precipitates that were not present in the AgNW stock or the growth medium. Both organic and inorganic coatings on the AgNW were transformed during ingestion or absorption. Pathway, gene ontology and clustering analyses of gene expression response indicated effects of AgNWs distinct from ionic silver on Daphnia magna. PMID:24099093
Kikuchi, Mani; Omori, Akihito; Kurokawa, Daisuke; Akasaka, Koji
2015-09-01
The presence of an anteroposterior body axis is a fundamental feature of bilateria. Within this group, echinoderms have secondarily evolved pentameral symmetric body plans. Although all echinoderms present bilaterally symmetric larval stages, they dramatically rearrange their body axis and develop a pentaradial body plan during metamorphosis. Therefore, the location of their anteroposterior body axis in adult forms remains a contentious issue. Unlike other echinoderms, sea cucumbers present an obvious anteroposterior axis not rearranged during metamorphosis, thus representing an interesting group to study their anteroposterior axis patterning. Hox genes are known to play a broadly conserved role in anteroposterior axis patterning in deuterostomes. Here, we report the expression patterns of Hox genes from early development to pentactula stage in sea cucumber. In early larval stages, five Hox genes (AjHox1, AjHox7, AjHox8, AjHox11/13a, and AjHox11/13b) were expressed sequentially along the archenteron, suggesting that the role of anteroposterior patterning of the Hox genes is conserved in bilateral larvae of echinoderms. In doliolaria and pentactula stages, eight Hox genes (AjHox1, AjHox5, AjHox7, AjHox8, AjHox9/10, AjHox11/13a, AjHox11/13b, and AjHox11/13c) were expressed sequentially along the digestive tract, following a similar expression pattern to that found in the visceral mesoderm of other bilateria. Unlike other echinoderms, pentameral expression patterns of AjHox genes were not observed in sea cucumber. Altogether, we concluded that AjHox genes are involved in the patterning of the digestive tract in both larvae and metamorphosis of sea cucumbers. In addition, the anteroposterior axis in sea cucumbers might be patterned like that of other bilateria.
Osteogenic Responses to Zirconia with Hydroxyapatite Coating by Aerosol Deposition
Cho, Y.; Hong, J.; Ryoo, H.; Kim, D.; Park, J.
2015-01-01
Previously, we found that osteogenic responses to zirconia co-doped with niobium oxide (Nb2O5) or tantalum oxide (Ta2O5) are comparable with responses to titanium, which is widely used as a dental implant material. The present study aimed to evaluate the in vitro osteogenic potential of hydroxyapatite (HA)-coated zirconia by an aerosol deposition method for improved osseointegration. Surface analysis by scanning electron microscopy and x-ray diffraction proved that a thin as-deposited HA film on zirconia showed a shallow, regular, crater-like surface. Deposition of dense and uniform HA films was measured by SEM, and the contact angle test demonstrated improved wettability of the HA-coated surface. Confocal laser scanning microscopy indicated that MC3T3-E1 pre-osteoblast attachment did not differ notably between the titanium and zirconia surfaces; however, cells on the HA-coated zirconia exhibited a lower proliferation than those on the uncoated zirconia late in the culture. Nevertheless, ALP, alizarin red S staining, and bone marker gene expression analysis indicated good osteogenic responses on HA-coated zirconia. Our results suggest that HA-coating by aerosol deposition improves the quality of surface modification and is favorable to osteogenesis. PMID:25586588
Pinger, Jason; Chowdhury, Shanin; Papavasiliou, F Nina
2017-10-10
Trypanosoma brucei is a protozoan parasite that evades its host's adaptive immune response by repeatedly replacing its dense variant surface glycoprotein (VSG) coat from its large genomic VSG repertoire. While the mechanisms regulating VSG gene expression and diversification have been examined extensively, the dynamics of VSG coat replacement at the protein level, and the impact of this process on successful immune evasion, remain unclear. Here we evaluate the rate of VSG replacement at the trypanosome surface following a genetic VSG switch, and show that full coat replacement requires several days to complete. Using in vivo infection assays, we demonstrate that parasites undergoing coat replacement are only vulnerable to clearance via early IgM antibodies for a limited time. Finally, we show that IgM loses its ability to mediate trypanosome clearance at unexpectedly early stages of coat replacement based on a critical density threshold of its cognate VSGs on the parasite surface. Trypanosoma brucei evades the host immune system through replacement of a variant surface glycoprotein (VSG) coat. Here, the authors show that VSG replacement takes several days to complete, and the parasite is vulnerable to the host immune system for a short period of time during the process.
Pattern transfer from nanoparticle arrays
NASA Astrophysics Data System (ADS)
Hogg, Charles R., III
This project contributes to the long-term extensibility of bit-patterned media (BPM), by removing obstacles to using a new and smaller class of self-assembling materials: surfactant-coated nanoparticles. Self-assembly rapidly produces regular patterns of small features over large areas. If these patterns can be used as templates for magnetic bits, the resulting media would have both high capacity and high bit density. The data storage industry has identified block copolymers (BCP) as the self-assembling technology for the first generation of BPM. Arrays of surfactant-coated nanoparticles have long shown higher feature densities than BCP, but their patterns could not previously be transferred into underlying substrates. I identify one key obstacle that has prevented this pattern transfer: the particles undergo a disordering transition during etching which I have called "cracking". I compare several approaches to measuring the degree of cracking, and I develop two novel techniques for preventing it and allowing pattern transfer. I demonstrate two different kinds of pattern transfer: positive (dots) and negative (antidots). To make dots, I etch the substrate between the particles with a directional CF4-based reactive ion etch (RIE). I find the ultrasmall gaps (just 2 nm) cause a tremendous slowdown in the etch rate, by a factor of 10 or more---an observation of fundamental significance for any pattern transfer at ultrahigh bit densities. Antidots are made by depositing material in the interstices, then removing the particles to leave behind a contiguous inorganic lattice. This lattice can itself be used as an etch mask for CF4-based RIE, in order to increase the height contrast. The antidot process promises great generality in choice of materials, both for the antidot lattice and the particles themselves; here, I present lattices of Al and Cr, ternplated from arrays of 13.7 nm-diameter Fe3O4 or 30 nm-diameter MnO nanoparticles. The fidelity of transfer is also noticeably better for antidots than for dots, making antidots the more promising technique for industrial applications. The smallest period for which I have shown pattern transfer (15.7 nm) is comparable to (but slightly smaller than) the smallest period currently shown for pattern transfer from block copolymers (17 nm); hence, my results compare favorably with the state of the art. Ultimately, by demonstrating that surfactant-coated nanoparticles can be used as pattern masks, this work increases their viability as an option to continue the exponential growth of bit density in magnetic storage media.
Three-dimensional visualization of coated vesicle formation in fibroblasts
1980-01-01
Fibroblasts apparently ingest low density lipoproteins (LDL) by a selective mechanism of receptor-mediated endocytosis involving the formation of coated vesicles from the plasma membrane. However, it is not known exactly how coated vesicles collect LDL receptors and pinch off from the plasma membrane. In this report, the quick-freeze, deep- etch, rotary-replication method has been applied to fibroblasts; it displays with unusual clarity the coats that appear under the plasma membrane at the start of receptor-mediated endocytosis. These coats appear to be polygonal networks of 7-nm strands or struts arranged into 30-nm polygons, most of which are hexagons but some of which are 5- and 7-sided rings. The proportion of pentagons in each network increases as the coated area of the plasma membrane puckers up from its planar configuration (where the network is mostly hexagons) to its most sharply curved condition as a pinched-off coated vesicle. Coats around the smallest vesicles (which are icosahedrons of hexagons and pentagons) appear only slightly different from "empty coats" purified from homogenized brain, which are less symmetrical baskets containing more pentagons than hexagons. A search for structural intermediates in this coat transformation allows a test of T. Kanaseki and K. Kadota's (1969. J. Cell Biol. 42:202--220.) original idea that an internal rearrangement in this basketwork from hexagons to pentagons could "power" coated vesicle formation. The most noteworthy variations in the typical hexagonal honeycomb are focal juxtapositions of 5- and 7-sided polygons at points of partial contraction and curvature in the basketwork. These appear to precede complete contraction into individual pentagons completely surrounded by hexagons, which is the pattern that characterizes the final spherical baskets around coated vesicles. PMID:6987244
Biomimetic composite coating on rapid prototyped scaffolds for bone tissue engineering.
Arafat, M Tarik; Lam, Christopher X F; Ekaputra, Andrew K; Wong, Siew Yee; Li, Xu; Gibson, Ian
2011-02-01
The objective of this present study was to improve the functional performance of rapid prototyped scaffolds for bone tissue engineering through biomimetic composite coating. Rapid prototyped poly(ε-caprolactone)/tri-calcium phosphate (PCL/TCP) scaffolds were fabricated using the screw extrusion system (SES). The fabricated PCL/TCP scaffolds were coated with a carbonated hydroxyapatite (CHA)-gelatin composite via biomimetic co-precipitation. The structure of the prepared CHA-gelatin composite coating was studied by scanning electron microscopy (SEM), X-ray photoelectron spectroscopy and Fourier transform infrared spectroscopy. Compressive mechanical testing revealed that the coating process did not have any detrimental effect on the mechanical properties of the scaffolds. The cell-scaffold interaction was studied by culturing porcine bone marrow stromal cells (BMSCs) on the scaffolds and assessing the proliferation and bone-related gene and protein expression capabilities of the cells. Confocal laser microscopy and SEM images of the cell-scaffold constructs showed a uniformly distributed cell sheet and accumulation of extracellular matrix in the interior of CHA-gelatin composite-coated PCL/TCP scaffolds. The proliferation rate of BMSCs on CHA-gelatin composite-coated PCL/TCP scaffolds was about 2.3 and 1.7 times higher than that on PCL/TCP scaffolds and CHA-coated PCL/TCP scaffolds, respectively, by day 10. Furthermore, reverse transcription polymerase chain reaction and Western blot analysis revealed that CHA-gelatin composite-coated PCL/TCP scaffolds stimulate osteogenic differentiation of BMSCs the most, compared with PCL/TCP scaffolds and CHA-coated PCL/TCP scaffolds. These results demonstrate that CHA-gelatin composite-coated rapid prototyped PCL/TCP scaffolds are promising for bone tissue engineering. Copyright © 2010 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.