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1.  Basal Expression of Pluripotency-Associated Genes Can Contribute to Stemness Property and Differentiation Potential 
Stem Cells and Development  2013;22(12):1802-1817.
Pluripotency and stemness is believed to be associated with high Oct-3/4, Nanog, and Sox-2 (ONS) expression. Similar to embryonic stem cells (ESCs), high ONS expression eventually became the measure of pluripotency in any cell. The threshold expression of ONS genes that underscores pluripotency, stemness, and differentiation potential is still unclear. Therefore, we raised a question as to whether pluripotency and stemness is a function of basal ONS gene expression. To prove this, we carried out a comparative study between basal ONS expressing NIH3T3 cells with pluripotent mouse bone marrow mesenchymal stem cells (mBMSC) and mouse ESC. Our studies on cellular, molecular, and immunological biomarkers between NIH3T3 and mBMSC demonstrated stemness property of undifferentiated NIH3T3 cells that was similar to mBMSC and somewhat close to ESC as well. In vivo teratoma formation with all three germ layer derivatives strengthen the fact that these cells in spite of basal ONS gene expression can differentiate into cells of multiple lineages without any genetic modification. Conclusively, our novel findings suggested that the phenomenon of pluripotency which imparts ability for multilineage cell differentiation is not necessarily a function of high ONS gene expression.
doi:10.1089/scd.2012.0261
PMCID: PMC3668502  PMID: 23343006
2.  Virus-mimicking nano-constructs as a contrast agent for near infrared photoacoustic imaging†‡ 
Nanoscale  2013;5(5):1772-1776.
We report the first proof-of-principle demonstration of photoacoustic imaging using a contrast agent composed of a plant virus protein shell, which encapsulates indocyanine green (ICG), the only FDA-approved near infrared chromophore. These nano-constructs can provide higher photoacoustic signals than blood in tissue phantoms, and display superior photostability compared to non-encapsulated ICG. Our preliminary results suggest that the constructs do not elicit an acute immunogenic response in healthy mice.
doi:10.1039/c3nr34124k
PMCID: PMC3626106  PMID: 23334567
3.  A Scientific Validation of Antihyperglycemic and Antihyperlipidemic Attributes of Trichosanthes dioica 
ISRN Pharmacology  2013;2013:473059.
The present study was undertaken to scientifically validate the antidiabetic activity of aqueous fruit extract of Trichosanthes dioica Roxb. (Family: Cucurbitaceae) which has been traditionally used for managing diabetes mellitus. This plant commonly known as “Sespadula” in English has not been explored scientifically so far for its glycemic potential except by our research group. The study was conducted with variable doses on normal, mild, and severe diabetics models, and several biochemical parameters including blood glucose level (BGL) were assessed. Maximum fall in BGL of 23.8% in normal rats and of 31.3% in mild diabetic rats was observed during their fasting blood glucose (FBG) and glucose tolerance test (GTT) with the dose of 1000 mg kg−1. In severely diabetic animals after 4 weeks treatment with FBG, postprandial glucose, total cholesterol, and triglyceride levels were reduced by 28.7, 30.7, 57.2, and 18.5%, whereas high density lipoprotein, total protein, hemoglobin, and body weight were increased by 33.0, 36.7, 15.7 and 16.7%, respectively. Moreover, urine sugar was reduced from +4 to +1. Thus, the study scientifically validates the traditional use of T. diocia in diabetes management and could be developed as an effective oral agent for treating diabetes mellitus and complications associated with it.
doi:10.1155/2013/473059
PMCID: PMC3747504  PMID: 23984089
4.  Prostate Stem Cells in the Development of Benign Prostate Hyperplasia and Prostate Cancer: Emerging Role and Concepts 
BioMed Research International  2013;2013:107954.
Benign Prostate hyperplasia (BPH) and prostate cancer (PCa) are the most common prostatic disorders affecting elderly men. Multiple factors including hormonal imbalance, disruption of cell proliferation, apoptosis, chronic inflammation, and aging are thought to be responsible for the pathophysiology of these diseases. Both BPH and PCa are considered to be arisen from aberrant proliferation of prostate stem cells. Recent studies on BPH and PCa have provided significant evidence for the origin of these diseases from stem cells that share characteristics with normal prostate stem cells. Aberrant changes in prostate stem cell regulatory factors may contribute to the development of BPH or PCa. Understanding these regulatory factors may provide insight into the mechanisms that convert quiescent adult prostate cells into proliferating compartments and lead to BPH or carcinoma. Ultimately, the knowledge of the unique prostate stem or stem-like cells in the pathogenesis and development of hyperplasia will facilitate the development of new therapeutic targets for BPH and PCa. In this review, we address recent progress towards understanding the putative role and complexities of stem cells in the development of BPH and PCa.
doi:10.1155/2013/107954
PMCID: PMC3722776  PMID: 23936768
5.  Effects of cholesterol on nano-mechanical properties of the living cell plasma membrane 
Soft matter  2012;8(32):8350-8360.
In this study, we investigated the effects of membrane cholesterol content on the mechanical properties of cell membranes by using optical tweezers. We pulled membrane tethers from human embryonic kidney cells using single and multi-speed protocols, and obtained time-resolved tether forces. We quantified various mechanical characteristics including the tether equilibrium force, bending modulus, effective membrane viscosity, and plasma membrane-cytoskeleton adhesion energy, and correlated them to the membrane cholesterol level. Decreases in cholesterol concentration were associated with increases in the tether equilibrium force, tether stiffness, and adhesion energy. Tether diameter and effective viscosity increased with increasing cholesterol levels. Disruption of cytoskeletal F-actin significantly changed the tether diameters in both non-cholesterol and cholesterol-manipulated cells, while the effective membrane viscosity was unaffected by F-actin disruption. The findings are relevant to inner ear function where cochlear amplification is altered by changes in membrane cholesterol content.
doi:10.1039/C2SM25263E
PMCID: PMC3515074  PMID: 23227105
7.  Effects of nanoencapsulation and PEGylation on biodistribution of indocyanine green in healthy mice: quantitative fluorescence imaging and analysis of organs 
Near-infrared nanoconstructs present a potentially effective platform for site-specific and deep tissue optical imaging and phototherapy. We have engineered a polymeric nanocapsule composed of polyallylamine hydrochloride (PAH) chains cross-linked with sodium phosphate and doped with indocyanine green (ICG) toward such endeavors. The ICG-doped nanocapsules were coated covalently with polyethylene glycol (5000 daltons) through reductive amination. We administrated the constructs by tail vein injection to healthy mice. To characterize the biodistribution of the constructs, we performed in vivo quantitative fluorescence imaging and subsequently analyzed the various extracted organs. Our results suggest that encapsulation of ICG in these PEGylated constructs is an effective approach to prolong the circulation time of ICG and delay its hepatic accumulation. Increased bioavailability of ICG, due to encapsulation, offers the potential of extending the clinical applications of ICG, which are currently limited due to rapid elimination of ICG from the vasculature. Our results also indicate that PAH and ICG-doped nanocapsules (ICG-NCs) are not cytotoxic at the levels used in this study.
doi:10.2147/IJN.S42511
PMCID: PMC3635661  PMID: 23637530
cancer; fluorescent imaging; nanoprobes; near infrared; pharmacokinetics; phototherapy; vascular imaging
8.  Spectrophotometric evaluation of the color changes of different feldspathic porcelains after exposure to commonly consumed beverages 
European Journal of Dentistry  2013;7(2):172-180.
Objective:
The aim of this study was to compare color stability and surface topography of three different feldspathic porcelains both qualitatively and quantitatively after exposure to routinely consumed beverages over different time periods using a Spectrophotometer, Stereomicroscope and Surface roughness tester, respectively.
Materials and Methods:
A total of 90 plastic discs were casted to obtain metal dies for three different newer ceramic applications each on thirty samples. The color and surface roughness of these samples were measured using stereomicroscope and surface roughness tester following which they were kept in different test solutions for different durations and revaluated for color changes and surface roughness in the similar manner.
Results and Conclusion:
Among all the five test solutions, Coffee showed the maximum staining of the ceramic whereas maximum surface roughness was shown by the Duceram Kiss (1.48 μm) by Orange Juice which could be due to its high titratable acidity.
doi:10.4103/1305-7456.110165
PMCID: PMC4023203  PMID: 24883022
Color stability; feldspathic porcelains; spectrophotometer
10.  Inhibition of 5′-UTR RNA Conformational Switching in HIV-1 Using Antisense PNAs 
PLoS ONE  2012;7(11):e49310.
Background
The genome of retroviruses, including HIV-1, is packaged as two homologous (+) strand RNA molecules, noncovalently associated close to their 5′-end in a region called dimer linkage structure (DLS). Retroviral HIV-1 genomic RNAs dimerize through complex interactions between dimerization initiation sites (DIS) within the (5′-UTR). Dimer formation is prevented by so calledLong Distance Interaction (LDI) conformation, whereas Branched Multiple Hairpin (BMH) conformation leads to spontaneous dimerization.
Methods and Results
We evaluated the role of SL1 (DIS), PolyA Hairpin signal and a long distance U5-AUG interaction by in-vitro dimerization, conformer assay and coupled dimerization and template-switching assays using antisense PNAs. Our data suggests evidence that PNAs targeted against SL1 produced severe inhibitory effect on dimerization and template-switching processes while PNAs targeted against U5 region do not show significant effect on dimerization and template switching, while PNAs targeted against AUG region showed strong inhibition of dimerization and template switching processes.
Conclusions
Our results demonstrate that PNA can be used successfully as an antisense to inhibit dimerization and template switching process in HIV -1 and both of the processes are closely linked to each other. Different PNA oligomers have ability of switching between two thermodynamically stable forms. PNA targeted against DIS and SL1 switch, LDI conformer to more dimerization friendly BMH form. PNAs targeted against PolyA haipin configuration did not show a significant change in dimerization and template switching process. The PNA oligomer directed against the AUG strand of U5-AUG duplex structure also showed a significant reduction in RNA dimerization as well as template- switching efficiency.The antisense PNA oligomers can be used to regulate the shift in the LDI/BMH equilibrium.
doi:10.1371/journal.pone.0049310
PMCID: PMC3495914  PMID: 23152893
11.  Dorsal Herniation of Cauda Equina Due to Sequestrated Intradural Disc 
Asian Spine Journal  2012;6(2):145-147.
Intradural lumbar disc herniation (ILDH) is uncommon pathology. In present report, authors present a case of ILDH associated with dorsal herniation of the cauda equina rootlets in a 30-year-old male laborer who had chronic backache since last two years. To the best of our knowledge we are reporting this for first time. Report demonstrates the natural course of ILDH.
doi:10.4184/asj.2012.6.2.145
PMCID: PMC3372551  PMID: 22708020
Intradural disc herniation; Duroplasty; Herniated cauda equina rootlets
12.  Amyloid Histology Stain for Rapid Bacterial Endospore Imaging ▿ †  
Journal of Clinical Microbiology  2011;49(8):2966-2975.
Bacterial endospores are some of the most resilient forms of life known to us, with their persistent survival capability resulting from a complex and effective structural organization. The outer membrane of endospores is surrounded by the densely packed endospore coat and exosporium, containing amyloid or amyloid-like proteins. In fact, it is the impenetrable composition of the endospore coat and the exosporium that makes staining methodologies for endospore detection complex and challenging. Therefore, a plausible strategy for facile and expedient staining would be to target components of the protective surface layers of the endospores. Instead of targeting endogenous markers encapsulated in the spores, here we demonstrated staining of these dormant life entities that targets the amyloid domains, i.e., the very surface components that make the coats of these species impenetrable. Using an amyloid staining dye, thioflavin T (ThT), we examined this strategy. A short incubation of bacillus endospore suspensions with ThT, under ambient conditions, resulted in (i) an enhancement of the fluorescence of ThT and (ii) the accumulation of ThT in the endospores, affording fluorescence images with excellent contrast ratios. Fluorescence images revealed that ThT tends to accumulate in the surface regions of the endospores. The observed fluorescence enhancement and dye accumulation, coupled with the sensitivity of emission techniques, provide an effective and rapid means of staining endospores without the inconvenience of pre- or posttreatment of samples.
doi:10.1128/JCM.02285-10
PMCID: PMC3147746  PMID: 21653779
13.  Prosthetic Rehabilitation of Ocular Defect Using Digital Photography: A Case Report 
The fundamental objective in restoring a congenital as well as acquired defect of eye with an ocular prosthesis is to enable the patient to cope better with the difficult process of rehabilitation after an enucleation or evisceration. A cosmetically acceptable prosthesis is that reproduces the color, form and orientation of iris and allows the patient to return to accustomed lifestyle. A sequence of steps for construction of custom-made ocular prostheses is outlined in this case report using the advantages of digital imaging technique.
doi:10.1007/s13191-010-0027-8
PMCID: PMC3081272  PMID: 21886412
Custom-made ocular prosthesis; Photographic iris; Digital imaging
14.  Non-invasive characterization of structure and morphology of silk fibroin biomaterials using non-linear microscopy 
Biomaterials  2008;29(13):2015-2024.
Designing biomaterial scaffolds remains a major challenge in tissue engineering. Key to this challenge is improved understanding of the relationships between the scaffold properties and its degradation kinetics, as well as the cell interactions and the promotion of new matrix deposition. Here we present the use of non-linear spectroscopic imaging as a non-invasive method to characterize not only morphological, but also structural aspects of silkworm silk fibroin-based biomaterials, relying entirely on endogenous optical contrast. We demonstrate that two photon excited fluorescence and second harmonic generation are sensitive to the hydration, overall β sheet content and molecular orientation of the sample. Thus, the functional content and high resolution afforded by these non-invasive approaches offer promise for identifying important connections between biomaterial design and functional engineered tissue development. The strategies described also have broader implications for understanding and tracking the remodeling of degradable biomaterials under dynamic conditions both in vitro and in vivo.
doi:10.1016/j.biomaterials.2007.12.049
PMCID: PMC2737252  PMID: 18291520
Silk; Fibroin; Non-linear Microscopy; Two-photon excited fluorescence; Second Harmonic Generation; Spectral Analysis; Non-invasive characterization
15.  Non-invasive Optical Characterization of Biomaterial Mineralization 
Biomaterials  2008;29(15):2359-2369.
Current approaches to study biomaterial mineralization are invasive and prevent dynamic characterization of this process within the same sample. Polarized light scattering spectroscopy (LSS) may offer a non-invasive alternative for assessing the levels of mineraliazation as well as some aspects of the organization of the mineral deposits. Specifically, we used LSS to characterize the formation of hydroxyapatite deposits on three types of silk films (water-annealed, methanol-treated and poly aspartic acid (PAA)-mixed) following 1, 3, 5 and 7 cycles of mineralization. We found that the total light scattering intensity provided a quantitative measure of the degree of mineralization as confirmed by thermal gravimetric analysis (TGA). The PAA-mixed silk films yielded the highest level of mineral deposition and the water-annealed ones the least, consistent with the β sheet content of the films prior to the onset of mineralization. The wavelength dependence of the singly backscattered light was consistent with a self-affine fractal morphology of the deposited films within scales in the range of 150 to 300 nm; this was confirmed by Fourier analysis of scanning electron microscopy (SEM) images of the corresponding films. The deposits of minerals in the water-annealed films were predominantly flake-like, with positively correlated density fluctuations (Hurst parameter, H>0.5), whereas methanol-treated and PAA-mixed silk films resulted in densely-packed, bulk mineral deposits with negatively correlated density fluctuations (H<0.5). Therefore, LSS could serve as a valuable tool for understanding the role of biomaterial properties in mineral formation, and, ultimately, for optimizing biomaterial designs that yield mineral deposits with the desired organization.
doi:10.1016/j.biomaterials.2008.01.034
PMCID: PMC2722932  PMID: 18313137
Silk; Fibroin; Tissue engineering; Polarization; Light scattering

Results 1-15 (15)