Antibody cross-reactivity among flaviviruses is a major limitation in understanding the prevalence without vector control measures. In this study, we investigated the presence of Zika virus (ZIKV)-specific antibodies and the significance of their cross-reactivity with other flaviviruses, which could affect the serological specificity in both symptomatic and asymptomatic pregnant women. Among the results obtained from 217 serum samples tested for ZIKV-specific IgM and IgG, no specific predictions regarding seropositivity or exposure due to extensive cross-reactivity with dengue virus (DENV) serology could be made.
View Article and Find Full Text PDFTGFBI-related corneal dystrophy (CD) is characterized by the accumulation of insoluble protein deposits in the corneal tissues, eventually leading to progressive corneal opacity. Here we show that ATP-independent amyloid-β chaperone L-PGDS can effectively disaggregate corneal amyloids in surgically excised human cornea of TGFBI-CD patients and release trapped amyloid hallmark proteins. Since the mechanism of amyloid disassembly by ATP-independent chaperones is unknown, we reconstructed atomic models of the amyloids self-assembled from TGFBIp-derived peptides and their complex with L-PGDS using cryo-EM and NMR.
View Article and Find Full Text PDFSelf-assembled peptide hydrogels have emerged as alternatives to the conventional approaches employed in controlled drug release, wound-healing, and drug delivery, and as anti-infective agents. However, peptide hydrogels possessing antibacterial properties are less explored. In this work, we have designed three ultrashort antibacterial peptide hydrogels: Fmoc-FFH-CONH, Fmoc-FHF-CONH, and Fmoc-HFF-CONH.
View Article and Find Full Text PDFSpatial confinement of excitons in the nano-crystalline region of semiconducting nanostructures differ significantly from the optoelectronic properties exhibited by the bulk material. We report spike-like absorption observed in the UV spectrum of a phenylalanine hexamer peptide [(Ff)-OH] nano-assembly, which may be attributed to the spatial confinement of electrons to the dimension of quantum dots. Interdependency of the UV and PLE spectrum of the peptide confirms the existence of quantum confinement in (Ff)-OH nano-assemblies.
View Article and Find Full Text PDFOnion (Allium cepa, L) is a very important vegetable crop in India. India is the second largest producer of onion in the world and the crop is grown on more than 1.22 million hectares.
View Article and Find Full Text PDFIn this paper, an exergetic optimization of simple and finned flat plate solar air collectors is established to determine the optimal design and operational parameters for humid subtropical climatic conditions. Solar air collectors are commonly used for space heating, irrigation, greenhouses, grain drying, hot air generation, etc. A detailed solar energy radiation model is developed for solar energy conversion.
View Article and Find Full Text PDFThe ability to modulate self-assembly is the key to manufacture application-oriented materials. In this study, we investigated the effect of three independent variables that can modulate the catalytic activity of self-assembling peptides. The first two variables, amino acid sequence and its stereochemistry, were examined for their specific roles in the epitaxial growth and hydrogelation properties of a series of catalytic tripeptides.
View Article and Find Full Text PDFTo evaluate the distribution of the transforming growth factor-beta induced (TGFBI) corneal dystrophies in a multi-ethnic population in Singapore, and to present the different phenotypes with the same genotype. This study included 32 patients. Slit lamp biomicroscopy was performed for each patient to determine the disease phenotype.
View Article and Find Full Text PDFThe impact of grapefruit seed extract (GFSE) as an antibacterial agent on citric acid (CA) crosslinked sodium carboxymethylcellulose (NaCMC)/hydroxypropylmethylcellulose (HPMC) hydrogel films has been studied by incorporating different quantities of GFSE. The prepared films were examined for their physical, thermal, mechanical and antibacterial properties. It was observed that crystallinity and initial decomposition temperature of hydrogel films decreased with GFSE concentration.
View Article and Find Full Text PDFIn this study, hydrogel films were prepared from sodium carboxymethylcellulose (NaCMC) and hydroxypropylmethylcellulose (HPMC) using citric acid (CA) as crosslinker. The chemical crosslinking (ester bond) between NaCMC and HPMC was confirmed by FTIR analysis. It was found that swelling degree, crystallinity and water contact angle of hydrogel films based on NaCMC-HPMC (2wt%) decrease with increase in CA from 5% to 20% (by weight).
View Article and Find Full Text PDFIn this study, zinc-sulfate-calcium-phosphate (ZSCAP) ceramics was prepared by calcination in the presence of microwave irradiation using precursors ZnSO:ZnO:CaO:PO in a ratio of 15:30:30:25 (by weight). The calcined ZSCAP ceramics was mixed with microcrystalline cellulose and it was further heated by microwave radiation for the preparation of cellulose/ZSCAP nanocomposites. It was found that microwave heating time played an important role in the crystalline phase of synthesized nanocomposites of cellulose/ZSCAP.
View Article and Find Full Text PDFCorneal stromal dystrophies are a group of genetic disorders that may be caused by mutations in the transforming growth factor β-induced () gene which results in the aggregation and deposition of mutant proteins in various layers of the cornea. The type of amino acid substitution dictates the age of onset, anatomical location of the deposits, morphological features of deposits (amyloid, amorphous powder or a mixture of both forms) and the severity of disease presentation. It has been suggested that abnormal turnover and aberrant proteolytic processing of the mutant proteins result in the accumulation of insoluble protein deposits.
View Article and Find Full Text PDFThe greater genomic conservation between humans and non-human primates (NHP) enables target validation studies for developing of therapeutic strategies for human diseases. Together with predicting activity and potential adverse clinical signs, the inclusion of NHP testing bequeaths to efficacy models for dose titration and pharmacodynamic effects. We have used lipid nanoparticle encapsulated siRNA to silence ApoB in the liver and assessed the phenotypic effects on serum lipids with various levels of hepatic ApoB mRNA knockdown in healthy lean cynomolgus monkeys.
View Article and Find Full Text PDFCorneal dystrophies are a group of inherited disorders localized to various layers of the cornea that affect corneal transparency and visual acuity. The deposition of insoluble protein materials in the form of extracellular deposits or intracellular cysts is pathognomic. Mutations in TGFBI are responsible for superficial and stromal corneal dystrophies.
View Article and Find Full Text PDFCotton leaf curl disease (CLCuD) is a major limitation to cotton production on the Indian subcontinent. A survey for viruses causing CLCuD was conducted during the 2009 and 2010 cropping seasons in the northwestern Indian cotton-growing belt in the states of Punjab, Haryana and Rajasthan. Partial sequences of 258 and full-length sequences of 22 virus genomes were determined.
View Article and Find Full Text PDFMounting an effective innate immune response against pathogens requires the rapid and global reprogramming of host cellular processes. Here we employed complementary proteomic methods to identify differentially regulated proteins early during a plant's defense response. Besides defense-related proteins, constituents of the largest category of upregulated proteins were cytoplasmic- and ER-residing molecular chaperones.
View Article and Find Full Text PDFSpectrochim Acta A Mol Biomol Spectrosc
June 2008
The clay index values of 60 different limestone samples collected from western Tamil Nadu were determined using UV-vis spectrophotometric method with the help of the absorbance value at 663 nm of a known concentration of methylene blue. The type of clay was determined as kaolinite through the FTIR technique. The applicability of this approach and advantages over the current methods in cement and chemical industries are demonstrated.
View Article and Find Full Text PDFThe plant innate immune response is mediated by resistance (R) genes and involves hypersensitive response (HR) cell death. During resistance responses, the host undergoes net changes in the transcriptome. To understand these changes, we generated a whole genome transcript profile for RCY1-mediated resistance to cucumber mosaic virus strain Y (CMV-Y) in Arabidopsis.
View Article and Find Full Text PDFSpectrochim Acta A Mol Biomol Spectrosc
September 2004
Single crystal electron paramagnetic resonance (EPR) studies of Mn(II) doped zinc potassium phosphate hexahydrate have been carried out at room temperature. Single crystal rotations along the three orthogonal axes indicate orthorhombic symmetry with spin-Hamiltonian parameters as: g(xx) = 1.9997; g(yy) = 1.
View Article and Find Full Text PDFIn the postgenomic era, large-scale functional genomic approaches are necessary for converting sequence information into functional information. A para-genetic approach, called virus-induced gene silencing (VIGS), offers a rapid means of gaining insight into gene function in plants. VIGS system could be used to suppress endogenous gene expression by infecting plants with a recombinant virus vector (VIGS vector) carrying host-derived sequence.
View Article and Find Full Text PDFSummary In this mini review we discuss recent advances in the understanding of the N gene-mediated resistance to tobacco mosaic virus (TMV). The tobacco N gene belongs to toll-interleukin-1 receptor homology/nucleotide binding/leucine rich repeat (TIR-NB-LRR) class of resistance genes. It encodes two transcripts, N(S) and N(L), by alternative splicing, both of which are required to confer resistance to TMV.
View Article and Find Full Text PDFPost-transcriptional gene silencing (PTGS) is a sequence-specific RNA degradation mechanism that is widespread in eukaryotic organisms. It is often associated with methylation of the transcribed region of the silenced gene and with accumulation of small RNAs (21 to 25 nucleotides) homologous to the silenced gene. In plants, PTGS can be triggered locally and then spread throughout the organism via a mobile signal that can cross a graft junction.
View Article and Find Full Text PDFSpectrochim Acta A Mol Biomol Spectrosc
December 2000
Single crystal EPR studies of VO(II)-doped magnesium potassium Tutton's salt have been carried out at room temperature. The results indicate that the paramagnetic impurity has entered the lattice, both substitutionally and interstitially and the maximum hyperfine for the substitutional site along the a axis corresponds to the minimum hyperfine for interstitial site and vice versa. The spin Hamiltonian parameters obtained from single crystal data for these sites are: Site 1, gparallel = 1.
View Article and Find Full Text PDFPosttranscriptional gene silencing (PTGS) is an ancient eukaryotic regulatory mechanism in which a particular RNA sequence is targeted and destroyed. The helper component-proteinase (HC-Pro) of plant potyviruses suppresses PTGS in plants. Using a yeast two-hybrid system, we identified a calmodulin-related protein (termed rgs-CaM) that interacts with HC-Pro.
View Article and Find Full Text PDFPost-transcriptional gene silencing (PTGS) is a fundamental regulatory mechanism operating in diverse types of organisms, but the cellular components of the gene silencing machinery and the regulation of the process are not understood. Recent findings that cytoplasmically replicating RNA viruses act as both targets and inducers of PTGS has led to the idea that PTGS may have evolved as an anti-viral defense mechanism in plants. Consistent with this hypothesis, it has been found that certain plant viruses encode proteins that suppress PTGS.
View Article and Find Full Text PDF