Metabolic engineering in E. coli for production of C-glycosylated flavones and their physio-chemical studies.

Shrestha,DipeshDhakal,RameshPrasadPandey,Jae Kyung Sohng 한국당과학회 2018 한국당과학회 학술대회 Vol.2018 No.07

Effect of Daylength on the Panicle Exsertion of Panicle Enclosing Gamadi Rice Cultivar

Shrestha,G,L,M,H,Heu,S,Z,Park 한국작물학회 1981 한국작물학회지 Vol.26 No.2

수도의 묘대일수가 절간신장에 미치는 영향

Gyan L. Shrestha갼 랄 슈레스터 韓國作物學會 1985 Korean journal of crop science Vol.30 No.2

네팔에서 보급단계로 진전된 수도 3계통 IET 7251, BG 400-1 및 B 44 b-50-2-2-5-1 을 6월 5일 파종하여 10일, 20일, 30일, 40일, 50일 및 60일 묘를 이앙하고 그들의 출수일수와 절간신장을 조사하여 다음과 같은 결과를 얻었다. 1. 간장은 30일묘 이앙구에서 가장 길었고 그보다 묘대일수가 길어짐에 따라 현저하게 간장이 단축되었다. 2. 육면으로 감별이 가능한 절수도 30일묘 이앙구에서 가장 많았는데 40일묘까지는 큰 차가 없었으나 그보다 묘대기간이 길어지면 유의하게 절수가 감소 되었다. 3. 간장은 40일묘 이앙구에서 가장 길었다. 4. 출수 및 성숙까지의 일수는 이앙이 늦어질수록 증가되었다. Three different improved pre-release rice varieties, when transplanted at different ages of seedlings, showed that 40 day old seedlings produced the longest panicle, whereas 30 day old seedlings produced the highest culm length among treatments in all treated varieties. 40 day or older seedlings reduced the culm length remarkably mainly due to decrease in lower internodes in IET7251 and BG400-1, and due to upper as well as lower internodes in B44b-50-2-2-5-1. 30 day old seedlings produced maximum number of visible internodes. Heading as weil as maturity was delayed with increasing age of seedling.

In vitro에서 큰번데기 동충하초 자실체형성의 불안정성

부샨 쓰레스타 외 한국버섯학회 2004 한국버섯학회지 Vol.2 No.3

Traditionally, Cordyceps species have been used as a part of herbal medicine in Oriental countries, including Korea for internal health, vigor and to cure different diseases related to heart, lung etc. In recent years, research on artificial fruiting of some species of the genus Cordyceps including C. militaris has been carried out extensively because of their medicinal value. Instability observed in the in vitro fruiting of C. militaris is reported in the present study. 전통적으로 Cordyceps종은 한국을 포함한 동양에서 건강증진과 심장과 폐에 관련된 질환을 치료하는 약용식물의 하나로 사용되어왔다. 최근에 동충하초의 약리적 가치 때문에 큰번데기 동충하초를 포함한 몇가지 Cordyceps종의 인공재배에 관한 연구가 활발하게 이루어지고 있다. 본 연구에서는 큰번데기 동충하초를 in vitro에서 인공재배한 결과 자실체 형성이 불안정한 것을 관찰하였기에 보고하고자 한다.

Assessment on Scaling-Up of Mini-Grid Initiative: Case Study of Mini-Grid in Rural Nepal

Pramish Shrestha,Ashish Shrestha,Namrata Tusuju Shrestha,Antonis Papadakis,Ramesh Kumar Maskey 한국정밀공학회 2021 International Journal of Precision Engineering and Vol.8 No.1

A majority of Nepalese population are living in rural areas, where the electricity access by grid extension is not feasible. Development of micro-hydropower in the isolated state is one of the solutions to provide the electricity to these areas. However, the micro-hydro systems are facing numerous challenges, such as high investment cost, low reliability, low load factor and protection issues. For this reason, the concept of mini-grid has been developed to address the discussed challenges. In this study, a case study of a mini-grid, which is formed by interconnecting six isolated Micro Hydropower Plants (MHPs) with an installed capacity of 107 kW at a transmission voltage of 11 kV, is considered. This study performs the technical and financial analysis, to study the possibility for scaling up the system. Based on different factors, optimum models have been selected, considering a numbers of different cases including cost–benefit and sensitivity analysis. The mini-grid connection of several isolated MHPs is technically possible, but the financial feasibility depends upon various factors, such as the distance between the MHPs, end-use promotion, total capacity of MHPs, future load growth, promotion mechanisms, power trading with utility, etc. The findings show that sustainable operation of mini-grid requires the local capacity building, coordination, and understanding among community cooperatives.

Relationship of the maxillary posterior teeth and maxillary sinus floor in different skeletal growth patterns: A cone-beam computed tomographic study of 1600 roots

Shrestha Biken,Shrestha Biken,Lu Hongfei,Mai Zhihui,Chen Lin,Chen Zheng,Ai Hong 대한영상치의학회 2022 Imaging Science in Dentistry Vol.52 No.1

Purpose: This study evaluated the distance from the posterior root apices to the maxillary sinus floor (MSF) and the frequency of roots touching or protruding through the MSF using cone-beam computed tomography (CBCT). Materials and Methods: This study included 100 subjects divided into different vertical and anteroposterior skeletal growth patterns. On CBCT images, the distance from the posterior root apices to MSF was measured and the frequency of roots touching or protruding through the MSF was evaluated using NNT software (version 5.3.0.0; ImageWorks, Elmsford, NY, USA). Results: No statistically significant differences were found in the distance from the posterior root apices to the MSF among vertical skeletal groups (P>0.05). The palatal roots of the first molar and the palatal, mesio-buccal and disto-buccal roots of the second molars had significantly less distance from MSF in skeletal class II than in class III (P<0.05). The high-angle group had the highest frequencies of roots touching or protruding into the maxillary sinus (49.8%); the lowest proportion of these roots was found in skeletal class III (28.3%) and the highest proportion in class II (50.3%). Males had shorter distances from the posterior root apices to the MSF and higher frequencies of roots protruding through or touching the MSF than females. Conclusion: Anteroposterior skeletal growth patterns and sex affected the distances from the maxillary posterior roots to the MSF. The frequency of roots protruding into or touching the sinus was affected by both vertical and anteroposterior skeletal groups and sex. These findings have implications for dental practice.

Bio-inspired hybrid scaffold of zinc oxide-functionalized multi-wall carbon nanotubes reinforced polyurethane nanofibers for bone tissue engineering

Shrestha, Bishnu Kumar,Shrestha, Sita,Tiwari, Arjun Prasad,Kim, Jeong-In,Ko, Sung Won,Kim, Han-Joo,Park, Chan Hee,Kim, Cheol Sang Elsevier 2017 Materials & Design Vol.133 No.-

<P><B>Abstract</B></P> <P>In this study, we prepared nanotopographical polyurethane (PU)-based bioactive scaffolds that incorporated uniformly dispersed functionalized multi-wall carbon nanotubes (<I>f</I>MWCNTs) and zinc oxide (ZnO) nanoparticles (NPs) using an electrospinning technique. We found that well dispersed <I>f</I>MWCNTs along with ZnO NPs reinforced PU fibers demonstrated significant improvement in mechanical strength, hydrophilicity, thermal stability, electrical conductivity, degradability, biomineralization, and biocompatibility. Inspired by the exciting nature of biopolymeric composite (PU/ZnO-<I>f</I>MWCNTs) membranes, these hybrid scaffolds offer extensive interest to tissue engineering as a potential biomedical application. The specific bioactive properties and cell-biomaterial interaction of electrospun scaffold containing 0.2wt% ZnO with 0.4wt% <I>f</I>MWCNTs were found to demonstrate anti-bacterial activity and cytocompatibility. Furthermore, the highly charged density, large surface-to-volume ratio, and more functional groups in <I>f</I>MWCNTs integrated on the scaffolds promote osteogenic differentiation of pre-osteoblast (MC3T3-E1) cells. Therefore, the novel as-prepared multifunctional electrospun fibrous scaffold could suggest new avenues for exploration as promising osteoproductive and osteoinductive biomaterials that offer great benefit to bone tissue engineering.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Functionalized multi-wall carbon nanotubes (<I>f</I>MWCNTs) within nanofiber enhance the electrical conductivity of scaffolds. </LI> <LI> The <I>f</I>MWCNTs (0.4 wt%) in scaffolds show good antibacterial activity. </LI> <LI> Interaction of zinc oxide and <I>f</I>MWCNTs with simulated body fluid resulting nucleation of calcium phosphate. </LI> <LI> The bioscaffolds exhibit excellent platform for osteogenic differentiation of pre-osteoblastic cells. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Preparation and field emission properties of Er-decorated multiwalled carbon nanotubes

Shrestha, S.,Choi, W.C.,Song, W.,Kwon, Y.T.,Shrestha, S.P.,Park, C.Y. Pergamon Press ; Elsevier Science Ltd 2010 Carbon Vol.48 No.1

The field emission of multiwalled carbon nanotubes (MWCNTs) was improved after decorating their external surface with erbium (Er)-nanoparticles. The decoration was performed by liquid-phase reduction using ethylene glycol as the reducing agent. The oxidation of MWCNTs and the attachment of Er-nanoparticles on the surface of MWCNTs were confirmed by transmission electron microscopy and energy-dispersive X-ray spectroscopy. Raman spectroscopy also revealed the oxidation and functionalization of the nanotubes. Thermogravimetric analysis showed that the decomposition temperature of the MWCNTs decreased gradually as a result of the oxidation process and sequential decoration with uniformly sized Er-nanoparticles (2-3nm). This means that some of the defects formed by oxidation and decoration with Er-nanoparticles reduced the ignition temperature of the MWCNTs. After decoration with Er-nanoparticles, the MWCNTs showed a significantly better emission current density (3.45mA/cm<SUP>2</SUP> at 3.98V/μm) and turn-on field (1.8V/μm) than the pristine MWCNTs.

δ-Catenin Increases the Stability of EGFR by Decreasing c-Cbl Interaction and Enhances EGFR/Erk1/2 Signaling in Prostate Cancer

Shrestha, Nensi,Shrestha, Hridaya,Ryu, Taeyong,Kim, Hangun,Simkhada, Shishli,Cho, Young-Chang,Park, So-Yeon,Cho, Sayeon,Lee, Kwang-Youl,Lee, Jae-Hyuk,Kim, Kwonseop Korean Society for Molecular and Cellular Biology 2018 Molecules and cells Vol.41 No.4

${\delta}$-Catenin, a member of the p120-catenin subfamily of armadillo proteins, reportedly increases during the late stage of prostate cancer. Our previous study demonstrates that ${\delta}$-catenin increases the stability of EGFR in prostate cancer cell lines. However, the molecular mechanism behind ${\delta}$-catenin-mediated enhanced stability of EGFR was not explored. In this study, we hypothesized that ${\delta}$-catenin enhances the protein stability of EGFR by inhibiting its lysosomal degradation that is mediated by c-casitas b-lineage lymphoma (c-Cbl), a RING domain E3 ligase. c-Cbl monoubiquitinates EGFR and thus facilitates its internalization, followed by lysosomal degradation. We observed that ${\delta}$-catenin plays a key role in EGFR stability and downstream signaling. ${\delta}$-Catenin competes with c-Cbl for EGFR binding, which results in a reduction of binding between c-Cbl and EGFR and thus decreases the ubiquitination of EGFR. This in turn increases the expression of membrane bound EGFR and enhances EGFR/Erk1/2 signaling. Our findings add a new perspective on the role of ${\delta}$-catenin in enhancing EGFR/Erk1/2 signaling-mediated prostate cancer.

π-Conjugated polyaniline-assisted flexible titania nanotubes with controlled surface morphology as regenerative medicine in nerve cell growth

Shrestha, Bishnu Kumar,Shrestha, Sita,Baral, Ek Raj,Lee, Ji Yeon,Kim, Beom-Su,Park, Chan Hee,Kim, Cheol Sang Elsevier 2019 CHEMICAL ENGINEERING JOURNAL -LAUSANNE- Vol.360 No.-

<P><B>Abstract</B></P> <P>Biologically active conjugated polymers, for example polyaniline (PANI), have drawn attention as emerging materials for applications in bio-medical implant devices, due to their inherent abilities with regard to charge-carrier properties, and their ability to immobilize biomolecules or proteins. Herein, we report an electrocoating of PANI on titania nanotubes (TNTs) via electrochemical oxidation of aniline with PANI layers of appropriate thickness (∼274 nm). Uniform titanium oxide nanotubes were first developed from titanium (Ti) foil through an anodization process, followed by calcination to obtain high purity TNTs vertically aligned on a Ti substrate. These had a large surface area, controllable tube height and diameter, and were highly biocompatible, and doping with PANI further improved their properties, like being antibacterial, having a lower charge transfer resistance (22.51 Ω) and strong anti-corrosion behavior (<I>E<SUB>corr</SUB> </I> ∼ − 184 mV, <I>I<SUB>corr</SUB> </I> ∼ 9.7 × 10<SUP>−7</SUP> Amp). <I>In vitro</I> experiments revealed that the cellular functions of PC12 and S42 cells on TNTs-PANI scaffolds show characteristic improvement in proliferation and differentiation owning to approach neuronal cells activation associated with axonal growth and migration in the peripheral nervous system (PNS). Thus, the flexible bioactive substrate is capable of stimulating neuronal cells, and can inspire neural transduction through direct neural interfaces.</P> <P><B>Highlights</B></P> <P> <UL> <LI> A highly conductive electroactive polyaniline (PANI) was electrodeposited uniformly on titania nanotubes (TNTs) substrate. </LI> <LI> Titania nanotubes-polyaniline (TNTs-PANI) showed antibacterial activity and corrosion resistivity. </LI> <LI> The biointerface TNTs-PANI was used as basal substrate for PC12 cells regeneration and differentiation. </LI> <LI> The flexible TNTs-PANI substrate accelerated the neurites outgrowth of PC12 cells. </LI> </UL> </P>