다양한 농작업 환경 미세먼지 노출관련 농작업자 면역력 변화

Maharjan Anju(Maharjan Anju ),Acharya Manju(Acharya Manju ),DaEun Lee(DaEun Lee),K.C. Pramod Bahadur(K.C. Pramod Bahadur ),Kusma Sarina(Kusma Sarina ),Adhikari Manisha(Adhikari Manisha ),ChangYul Kim( 한국환경보건학회 2022 한국환경보건학회 학술대회 자료집 Vol.2022 No.5

Evaluation of epithelial transport and oxidative stress protection of nanoengineered curcumin derivative-cyclodextrin formulation for ocular delivery

Pooja Maharjan,Minki Jin,Daseul Kim,JaeWook Yang,Anjila Maharjan,Meong Cheol Shin,Kwan Hyung Cho,김만수,Kyoung Ah Min 대한약학회 2019 Archives of Pharmacal Research Vol.42 No.10

Ocular drug delivery has been a well-knownroute for the drug administration for the treatment of oculardiseases. However, numerous anatomical and physiologicalbarriers prevailing in the eye itself create considerablechallenges for achieving the necessitated therapeutic efficacyalong with ocular bioavailability. However, recentadvances in nanoengineered strategies hold definite promisesin terms of devising improved ophthalmic medicinesfor the effective drug delivery to target the sites withenhanced ocular bioavailability. Curcumin, a hydrophobicpolyphenol yellow colored compound, and its metabolicreduced product, tetrahydrocurcumin (THC), have beenknown for their beneficial pharmacological functions, suchas anti-inflammatory or anti-oxidant activities at varioustissue sites. However, the low aqueous solubility of thesecompounds results in their poor bioavailability, therebylimiting their widespread application. Therefore, in thepresent study, we investigated the changes in drug solubilityby forming inclusion complexes with differentderivatives of hydroxypropyl (HP)-cyclodextrins (CD). To this end, the spray drying technique was used for nanoengineeringcurcumin or THC-loaded formulations toimprove the stability of formulations during the storage. The formulations were characterized in terms of physicochemicalproperties and cellular permeability. The resultsdemonstrated that the encapsulation of curcumin (or THC)into the HP-CDs significantly increased the drug solubilityand enhanced the corneal and retinal epithelial permeability. Curcumin or THC complexes in HP-CDs withimproved bioavailability also induced anti-oxidant activity(SOD1, CAT1, and HMOX1) in higher levels in the ocularepithelial cells and showed oxidative protection effects inrabbit cornea tissues that will boost up their application inocular medicine.

Effect of proton-beam irradiation on cell survival of MCF-7 and its chemo-resistant subgroups

Maharjan Sushma,Lee Min-Gu,Nam Kyung-Soo,Lee Kyu-Shik 한국물리학회 2024 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.85 No.3

Proton beam (PB) therapy is gaining popularity for breast cancer treatment because of its enhanced coverage and potential to minimize late toxicities. The dose and volume of PB irradiation are closely associated with improved breast cancer survival. We aimed to investigate the impact of PB irradiation on the survival of the human breast cancer cells MCF-7 and their resistance to doxorubicin (MCF-7-DR) and paclitaxel (MCF-7-PR). Cells exposed to 0.5, 2, 4, or 8 Gy of PB irradiation showed a signifcant decrease in the survival of parent cells, even at 2 Gy, indicating therapeutic efcacy. Conversely, drug-resistant cells exhibited notable cytotoxicity at 4 and 8 Gy, which were above the daily recommended dose. Mechanistically, PB irradiation signifcantly altered the DNA repair proteins RAD51, Ku80, and survivin and cleaved PARP in MCF-7 cells compared to chemo-resistant cells, except for RAD51 and Ku80. In addition, cell-cycle regulators and MAPK expression were notably altered by PB irradiation compared to MCF-7-DR and PR cells, underscoring the importance of tailoring PB irradiation for enhanced efcacy against chemo-resistant breast cancer. These fndings suggest that PB irradiation downregulated RAD51 and Ku80, the potent DNA repair markers, underscoring its potential therapeutic efcacy in treating chemo-resistant breast cancer cells.

Metabolic engineering of Nocardia sp. CS682 for enhanced production of nargenicin A1.

Maharjan, Sushila,Koju, Dinesh,Lee, Hei Chan,Yoo, Jin Cheol,Sohng, Jae Kyung Humana Press 2012 Applied biochemistry and biotechnology Vol.166 No.3

<P>A number of secondary metabolites having therapeutic importance have been reported from the genus Nocardia. One of the polyketide antibiotic compounds isolated from Nocardia is nargenicin A(1). Recently, nargenicin A(1) has been isolated from Nocardia sp. CS682, a new Nocardia strain isolated from soil in Jeonnam, South Korea. It possesses strong antibacterial activity against methicillin-resistant Staphylococcus aureus. In this study, we applied a metabolic engineering approach based on recombinant DNA technology in order to boost the production of nargenicin A(1) from Nocardia sp. CS682. Initially, we optimized the transformation of this new strain by electroporation method. Heterologous expression of S-adenosylmethionine synthetase (MetK1-sp) in Nocardia sp. CS682 enhanced the production of nargenicin A(1) by about 2.8 times due to transcriptional activation of biosynthetic genes as revealed by reverse transcription polymerase chain reaction analysis. Similarly, expression of acetyl-CoA carboxylase genes improved nargenicin A(1) production by about 3.8 times in Nocardia sp. ACC18 compared to that in Nocardia sp. CS682 and Nocardia sp. NV18 by increasing precursor pool. Thus, enhanced production of nargenicin A(1) from Nocardia sp. CS682 can be achieved by expression of transcriptional activator genes and precursor genes from Streptomyces strains.</P>

Olfactory Response and Feeding Preference of Liriomyza huidobrensis (Diptera: Agromyzidae) to Potato Cultivars

Maharjan, R.,Jung, C. Entomological Society of America 2016 Environmental entomology Vol.45 No.5

<P>Liriomyza huidobrensis (Blanchard) is a serious invasive pest of potato in Korea. In sessile insect herbivores like leafminer flies, host plant choice is a critical decision made by adults for offspring survival, and one that is often influenced by host plant quality. In annual host plants like potato, leafminer choice is sometimes influenced by cultivar characteristics. To determine the basis of host selection, the odor and feeding preferences of adult L. huidobrensis were examined using a five-arm olfactometer offering a choice of five different potato cultivars: 'Chubeak', 'Seohong', 'Goun', 'Dejima', and 'Sumi'. Preferences of adult leafminers varied significantly among potato cultivars. Liriomyza huidobrensis showed a preference for the Goun cultivar in both olfactory and adult feeding tests. When measured 2 wk after release onto actual plants, plant damage ratings and the number of mines were consistent with the feeding preference results. Further studies should examine the influence of cultivar characteristics on larval fitness and adult longevity to develop a resistant potato cultivar through the selection behavior of leafminers.</P>

In-situ synthesis of AgNPs in the natural/synthetic hybrid nanofibrous scaffolds: Fabrication, characterization and antimicrobial activities

Maharjan, Bikendra,Joshi, Mahesh Kumar,Tiwari, Arjun Prasad,Park, Chan Hee,Kim, Cheol Sang Elsevier 2017 Journal of the mechanical behavior of biomedical m Vol.65 No.-

<P><B>Abstract</B></P> <P>Silver nanoparticles embedded within a nanofibrous polymer matrix have significant attention in recent years as an antimicrobial wound dressing materials. Herein, we have fabricated a novel Ag-polyurethane-zein hybrid nanofibrous scaffold for wound dressing applications. AgNPs were synthesized in-situ via reduction of silver nitrate in electrospinning solution. Varying mass composition of the components showed the pronounced effect on the morphology and physicochemical properties of the composite fibers. Field-Emission Scanning Electron Microscopy (FESEM) images revealed that PU and zein with mass ratio 2:1 produced the bead-free continuous and uniformly distributed nanofibers. Fourier-transform Infrared Spectroscopy (FTIR), X-ray diffraction (XRD) and Thermogravimetric Analysis (TGA) confirmed the well interaction between component polymers. Compared to the pristine PU nanofibers, composite fibers showed enhanced tensile strength, young׳s modulus and surface wettability. The antibacterial capacity of the nanofibrous membrane was evaluated against gram-positive (<I>Staphylococcus aureus</I>) and gram-negative (<I>Escherichia coli</I>) bacterial strains via a zone of inhibition test, and the results showed high antibacterial performance for Ag incorporated composite mat. Experimental results of cell viability assay and microscopic imaging revealed that as-fabricated scaffolds have an excellent ability for fibroblast cell adhesion, proliferation and growth. Overall, as-fabricated antibacterial natural/synthetic composite scaffold can be a promising substrate for repairing skin defects.</P> <P><B>Highlights</B></P> <P> <UL> <LI> A novel antibacterial natural/synthetic hybrid nanofibrous scaffold. </LI> <LI> Synthetization of AgNPs by in-situ reduction of silver nitrate in solution. </LI> <LI> Wettability and bioactivity of PU fiber improved by blending with biopolymer zein. </LI> <LI> Composite fibers showed enhanced tensile strength and young’s modulus. </LI> <LI> As-fabricated composite scaffold can be promising substrate for skin repairing. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Feeding behavior and development response of the perilla seed bugs (Nysius sp.) (Heteroptera: Lygaeidae) on multiple crop seeds combinations

Maharjan Rameswor,Yoon Youngnam,Jang Yunwoo,Jeong Mihye,박기도,Yi Hwijong 한국응용곤충학회 2021 Journal of Asia-Pacific Entomology Vol.24 No.4

The perilla seed bugs, Nysius plebeius Distant and Nysius hidakai Nakatani, are emerging pests of several field crop species including perilla crop in Korea. Here, we investigated the oviposition, nymphal mortality, development, adult emergence, adult longevity, adult weight and female ratio of N. plebeius and N. hidakai on multiple (MC) and double (DC) combinations of five crop seed species: perilla [Perilla frutescens (L.) Britton.], sesame (Sesamum indicum L.), sorghum [Sorghum bicolor (L.)], proso millet (Panicum miliaceum L.), and foxtail millet (Setaria italic L.) in no-choice test. The life-history variables of N. plebeius and N. hidakai were significantly influenced by the crop seed combinations. The most preferred crop seed combinations for oviposition were MC (perilla + sorghum + sesame + proso millet + foxtail millet), followed by DC (perilla + foxtail millet and perilla + sorghum), whereas the least preferred seed combination was DC (proso millet + foxtail millet). Both Nysius sp. were developed faster in MC (perilla + sorghum + sesame + proso millet + foxtail millet), with minimal nymphal mortality, higher adult emergence, longer adult longevity and heavier adult weight. The positive adult bug’s performance on the MC (perilla + sorghum + sesame + proso millet + foxtail millet) may be due to the nutrient contents and physicochemical components associated with the crop seeds. Further, the findings of this study are discussed in terms of bug’s behavioral response to crop seed species combinations and management strategies of Nysius sp. as an alternative to chemical management.

Prevalence of Puccinia abrupta var. partheniicola and its impact on Parthenium hysterophorus in Kathmandu Valley, Nepal

Maharjan, Seerjana,Devkota, Anjana,Shrestha, Bharat Babu,Baniya, Chitra Bahadur,Rangaswamy, Muniappan,Jha, ramod Kumar The Ecological Society of Korea 2020 Journal of Ecology and Environment Vol.44 No.4

Background: Parthenium hysterophorus is a noxious invasive weed in tropical and subtropical regions of the world, including Nepal. Among 11 species of biological control agents released to control P. hysterophorus in Ausrtalia, winter rust Puccina abrupta var. partheniicola arrived fortuitously and has established in Kathmandu Valley, Nepal, nearly a decade back. However, the prevalence and effectiveness of this rust as a biological control agent in Kathmandu remain unknown. To address this knowledge gap, a roadside survey was done at an interval of 2 ± 0.25 km in Kathmandu Valley to assess the P. abrupta var. partheniicola incidence and its impacts on P. hysterophorus. Infested individuals of P. hysterophorus were further divided into four severity classes (very low, low, medium, and high), and rust incidence was calculated. The impact of the winter rust on the growth of P. hysterophorus was assessed by comparing biomass and seed output of infested and non-infested individuals. Results: Among 81 locations where P. hysterophorus was present in the Kathmandu Valley, winter rust infestation was observed at 98% locations. At some locations within Kathmandu Valley such as Tinkune, Kirtipur, Chabahil, Buddha Chowk, and Dhobighat, the impacts of the rust on P. hysterophorus were medium to high. Aboveground biomass and seed output of P. hysterophorus were reduced by 47% and 73%, respectively, due to winter rust infestation. The study indicates that winter rust incidence is widespread in Kathmandu Valley with very low to high levels of damages to P. hysterophorus depending on the localities. Conclusion: The rust has, therefore, a potential to reduce the growth performance of P. hysterophorus, and it can be used as a component of integrated management of P. hysterophorus by introducing to other suitable areas in Nepal.

Microstrip Cross-coupled Interdigital SIR Based Bandpass Filter

Maharjan, R.K.,Shrestha, B.,Kim, N.Y. Radioengineering Society 2012 Radioengineering Vol.21 No.3

Microstrip Bandpass Filters Using Window Hairpin Resonator and T-Feeder Coupling Lines

Maharjan, R. K.,Kim, N. Y. KING FAHD UNIVERSITY OF PETROLEUM MINERALS 2014 Arabian journal for science and engineering: AJSE Vol.39 No.5

A new structure of planar window hairpin-based bandpass filters with symmetrical T-shaped feeder coupling line resonators is introduced. With varying different width in X axis and length in Y axis of the window of the hairpin resonator configuration, correspondingly the changes can be observed in the resonant frequency and useable bandwidth. By these methods, frequency tuning can be easily achieved by adjusting hairpin window dimension of the structure. Both filters were designed for 5.205 GHz resonant frequency. The geometrical window hairpin structure areas of both type filters are quite similar and both filters are resonated at almost the same frequency. The measurement results show that return loss (S-11) for both filters is higher than 23.0 dB and insertion loss (S-21) is measured less than -1.4 dB at resonant frequency of 5.13 GHz. The S-parameter responses of the fabricated filter nearly match with the electromagnetic simulated results; therefore, the feasibility of practical application of the proposed filters can be expected.