Liquid crystalline nanoparticles encapsulating cisplatin and docetaxel combination for targeted therapy of breast cancer

Thapa, R.,Choi, J.,Gupta, B.,Ramasamy, T.,Poudel, B.,Ku, S.,Youn, Y.,Choi, H.,Yong, C.,Kim, J. Royal Society of Chemistry 2016 Biomaterials science Vol.4 No.9

<P>Cancer remains a leading cause of death. A combination of anticancer agents can effectively kill cancer through multiple pathways; however, improvements to their delivery are needed. Hence, docetaxel and cisplatin-loaded liquid crystalline nanoparticles with folic acid were prepared for effective and targeted anticancer therapy. Notably, hydroxypropyl-beta-cyclodextrin/cisplatin complexes in 0.9% NaCl solution were used for the prevention of possible aquation of cisplatin, which would otherwise lead to severe adverse effects. The optimized nanoparticles exhibited small particle size, high drug loading capacity (>90%), and controlled drug release profiles. In vitro cell cytotoxicity assays demonstrated that the optimized nanoparticles were taken up by folate receptor-expressing cells to a greater extent than non-folate expressing cells, which is attributable to folate-specific endocytosis of the optimized nanoparticles. Enhanced expression of apoptotic markers (Bax, p21, and cleaved caspase-3) along with enhanced anti-migration effects in MDA-MB-231 cells following treatment suggests that the optimized nanoparticles provide an effective treatment for metastatic breast cancer. These results were further supported by in vivo findings obtained for a MDA-MB-231 tumor xenograft model. Altogether, the optimized nanoparticles may potentially be developed as an effective treatment modality for folate-targeted metastatic breast cancer treatment.</P>

A Deep Learning-Based Defect Detection and Inverse Design of Block Copolymer System

안지훈,Vikram Thapar,허수미 한국고분자학회 2021 한국고분자학회 학술대회 연구논문 초록집 Vol.46 No.2

Recently, as an emerging paradigm of material science, deep learning has shown its potential in various research fields; there have been attempts to apply deep learning in designing molecules’ structures, analyzing spectral data, and even sampling more accurate free energy landscapes. Among this unlimited potential of deep learning technology, image processing using deep learning has been particularly outstanding. Here, we propose deep learning algorithms to identify defects and quantify the ordering qualities in lamella- and cylinder-forming block copolymer films, replacing conventional defect inspection tools involved with either manual defect detections or inefficient image processing steps. We further use the developed deep learning neural networks for an inverse design of system parameters to achieve a targeting self-assembled structure.

Defect Annihilation Pathways in Directed Assembly of Lamellar Block Copolymer Thin Films

Hur, Su-Mi,Thapar, Vikram,Ramí,rez-Herná,ndez, Abelardo,Nealey, Paul F.,de Pablo, Juan J. American Chemical Society 2018 ACS NANO Vol.12 No.10

<P>Defects in highly ordered self-assembled block copolymers represent an important roadblock toward the adoption of these materials in a wide range of applications. This work examines the pathways for annihilation of defects in symmetric diblock copolymers in the context of directed assembly using patterned substrates. Past theoretical and computational studies of such systems have predicted minimum free energy pathways that are characteristic of an activated process. However, they have been limited to adjacent dislocations with opposite Burgers vectors. By relying on a combination of advanced sampling techniques and particle-based simulations, this work considers the long-range interaction between dislocation pairs, both on homogeneous and nanopatterned substrates. As illustrated here, these interactions are central to understanding the defect structures that are most commonly found in applications and in experimental studies of directed self-assembly. More specifically, it is shown that, for dislocation dipoles separated by several lamellae, multiple consecutive free energy barriers lead to effective kinetic barriers that are an order of magnitude larger than those originally reported in the literature for tightly bound dislocation pairs. It is also shown that annihilation pathways depend strongly on both the separation between dislocations and their relative position with respect to the substrate guiding stripes used to direct the assembly.</P> [FIG OMISSION]</BR>

Hemobilia due to arteriobiliary fistula complicating ERCP for residual bile duct stone in a case of Mirizzi syndrome

Surendrakumar Mathur,Vinaykumar Thapar,Vasudev Chowda 한국간담췌외과학회 2017 Annals of hepato-biliary-pancreatic surgery Vol.21 No.2

Hemobilia is a rare cause of upper gastrointestinal tract bleeding. Most cases are iatrogenic following medical interventions, most commonly liver biopsy and transhepatic cholangiography. We present a case of arteriobiliary fistula between the right hepatic artery and the common hepatic duct, in a case of Mirrizi syndrome, following endoscopic biliary stenting and presenting with hemobilia. The patient was treated by surgical disconnection of the fistula, ligation of the right hepatic artery, and bilioenteric anastomosis.

Factors Controlling Uranium Level in Granitic Aquifer

YeoJin Ju,Vikram Thapar,Ji-hun Ryu 한국방사성폐기물학회 2022 한국방사성폐기물학회 학술논문요약집 Vol.20 No.2

Uranium (U) is hazardous material can cause chemical and radiological toxicity, e.g., kidney toxicity and health effects associated with radiation. In Korea, where shallow weathered granitic aquifers are ubiquitous, several previous studies have reported high level of radioactivity in shallow groundwater. This eventually led to the closure of 60 out of 4,140 groundwater production wells in South Korea. Here, we examined aquifers currently dedicated for drinking water supply and investigated the 11,225 dataset of 103 environmental parameters. This dataset includes 80 physical parameters associated with the hydraulic system and 23 chemical parameters associated with waterrock interactions. Among hydraulic parameters, coarse loamy texture in subsoil displayed a notable relation with U concentration level, implied it is controlling the leaching of U from host rocks. Fluorine (F), is one of major products from water-rock interaction in granitic aquifer, exhibited high correlation with U concentration distribution. Positive relation of F concentration with uranium level suggested the dissolved U originated from groundwater interacted with granites. Conclusively, we found that infiltration capacity of soil layers and (2) aqueous speciation in groundwater formulated by interaction of groundwater with local solids, played important role for U concentration in granitic aquifer.

Dentofacial and Cranial Changes in Down Syndrome

Deepika Shukla,Deepika Bablani,Aman Chowdhry,Raveena Thapar,Puneet Gupta,Shashwat Mishra 질병관리본부 2014 Osong Public Health and Research Persptectives Vol.5 No.6

Objectives: This study aimed to determine the prevalence of certain oral characteristics usually associated with Down syndrome and to determine the oral health status of these patients. Methods: The cross-sectional study was conducted among patients attending a special education program at Faculty of Dentistry, Jamia Millia Islamia, Delhi, India. The study design consisted of closed-ended questions on demographic characteristics (age, sex, and education and income of parents), dietary habits, and oral hygiene habits. Clinical examination included assessment of oral hygiene according to Simplified Oral Hygiene Index (OHI-S), dental caries according to decayed, missing, and filled teeth (DMFT) index, periodontal status according to the Community Periodontal Index of Treatment Needs (CPITN), and malocclusion according to Angles classification of malocclusion. Examinations were carried out using a using a CPI probe and a mouth mirror in accordance with World Health Organization criteria and methods. Craniometric measurements, including maximum head length and head breadth were measured for each participant using Martin spreading calipers centered on standard anthropological methods. Results: The majority of the patients were males (n = 63; 82%) with age ranging from 6e40 years. The Intelligence Quotient (IQ) score of the patients indicated that 31% had moderate mental disability and 52% had mild mental disability. 22% exhibited hearing and speech problems.12% had missing teeth and 15% had retained deciduous teeth in adult population. The overall prevalence of dental caries in the study population was 78%. DMFT, CPITN and OHI scores of the study group were 3.8 ± 2.52, 2.10 ± 1.14 and 1.92 ± 0.63 respectively. The vast majority of patients required treatment (90%), primarily of scaling, root planing, and oral hygiene education. 16% of patients reported CPITN scores of 4 (deep pockets) requiring complex periodontal care. The prevalence of malocclusion was 97% predominantly of Class III malocclusions. Further 14% presented with fractured anterior teeth primarily central incisor. The percentage means of cephalic index was 84.6% in the study population. The brachycephalic and hyperbrachycephalic type of head shape was dominant in the Down syndrome individuals (90%). Conclusion: The most common dentofacial anomaly seen in these individuals was fissured tongue followed by macroglossia.

Effect of separate and mixed refining of hardwood and softwood pulps on paper properties

Vipul S. Chauhan,Nitin Kumar,Manoj Kumar,Swapan K. Chakrabarti,S. K. Thapar 한국펄프·종이공학회 2011 펄프.종이기술 Vol.43 No.4

Enhanced Isolation and Release of Circulating Tumor Cells Using Nanoparticle Binding and Ligand Exchange in a Microfluidic Chip

Park, Myoung-Hwan,Reá,tegui, Eduardo,Li, Wei,Tessier, Shannon N.,Wong, Keith H. K.,Jensen, Anne E.,Thapar, Vishal,Ting, David,Toner, Mehmet,Stott, Shannon L.,Hammond, Paula T. American Chemical Society 2017 JOURNAL OF THE AMERICAN CHEMICAL SOCIETY - Vol.139 No.7

<P>The detection of rare circulating tumor cells (CTCs) in the blood of cancer patients has the potential to be a powerful and noninvasive method for examining metastasis, evaluating prognosis, assessing tumor sensitivity to drugs, and monitoring therapeutic outcomes. In this study, we have developed an efficient strategy to isolate CTCs from the blood of breast cancer patients using a microfluidic immune-affinity approach. Additionally, to gain further access to these rare cells for downstream characterization, our strategy allows for easy detachment of the captured CTCs from the substrate without compromising cell viability or the ability to employ next generation RNA sequencing for the identification of specific breast cancer genes. To achieve this, a chemical ligand-exchange reaction was engineered to release cells attached to a gold nanoparticle coating bound to the surface of a herringbone microfluidic chip (NP-(CTC)-C-HB-Chip). Compared to the use of the unmodified (CTC)-C-HB-Chip, our approach provides several advantages, including enhanced capture efficiency and recovery of isolated CTCs.</P>