A multi-functional polyhydroxybutyrate nanoparticle for theranostic applications

Kwon, Hee-Su,Jung, Sung-Geun,Kim, Hae-Yeong,Parker, Stephanie A.,Batt, Carl A.,Kim, Young-Rok The Royal Society of Chemistry 2014 Journal of Materials Chemistry B Vol.2 No.25

<P>Biopolymer-based multi-functional nanoparticles have been developed through a one-step enzymatic polymerization reaction using engineered polyhydroxyalkanoate (PHA) synthase fused with green fluorescent protein (GFP) and a single chain variable fragment antibody (A33scFv) specific to colon cancer. PHA synthase possesses unique catalytic characteristics, namely covalent catalysis, by which the synthesized polyhydroxybutyrate chain remains covalently attached to the enzyme. The amphiphilic nature of the resulting protein-polymer hybrid gives rise to spontaneous self-assembly into a micellar structure with GFP and A33scFv displayed on the surface (AGPHB nanoparticle). A model compound, Nile red, was loaded into the hydrophobic core of the AGPHB nanoparticle during the polymerization and self-assembly process. The specificity of the fluorescent multi-functional AGPHB nanoparticle towards the colon cancer cell lines SW1222 (A33+) and HT29 (A33−) was confirmed and analysed quantitatively <I>in vitro</I>. This new biological approach provides a simple means of producing nanocarriers with a range of surface functionality and the sizes desired for imaging and targeted drug delivery.</P>

Phorbaketal A stimulates osteoblast differentiation through TAZ mediated Runx2 activation

Byun, Mi Ran,Kim, A Rum,Hwang, Jun-Ha,Sung, Mi Kyung,Lee, Yeon Kyung,Hwang, Buyng Su,Rho, Jung-Rae,Hwang, Eun Sook,Hong, Jeong-Ho Elsevier 2012 FEBS letters Vol.586 No.8

<P><B>Highlights</B></P><P>► Phorbaketal A stimulates osteogenesis. ► Phorbaketal A increases TAZ-mediated osteoblast marker gene expression. ► ERK is an important kinase for phorbaketal A induced osteogenic differentiation. ► Phorbaketal A is suggested as a potential compound for stimulating bone formation.</P> <P><B>Abstract</B></P><P>Osteoporosis arises from an imbalance between osteoblastic bone formation and osteoclastic bone resorption. In this study, we screened molecules from marine natural products that stimulate osteoblast differentiation. We found that phorbaketal A significantly stimulates osteoblast differentiation in mesenchymal cells. Increased interaction of TAZ and Runx2 stimulated phorbaketal A-induced expression of osteoblastic marker genes. The activation of ERK was important for the stimulation of differentiation because an inhibitor of ERK blocked phorbaketal A-induced osteogenic differentiation. Taken together, the results showed that phorbaketal A stimulates TAZ-mediated osteoblast differentiation through the activation of ERK.</P><P><B>Structured summary of protein interactions</B></P><P><B>TAZ</B> physically interacts with <B>RUNX2</B> by pull down (View interaction)</P>

Characteristics of a-GaN films and a-AlGaN/GaN heterojunctions prepared on r-sapphire by two-stage growth process

Polyakov, A. Y.,Jang, Lee-Woon,Smirnov, N. B.,Govorkov, A. V.,Kozhukhova, E. A.,Yugova, T. G.,Reznik, V. Y.,Pearton, S. J.,Baik, Kwang Hyeon,Hwang, Sung-Min,Jung, Sukkoo,Lee, In-Hwan American Institute of Physics 2011 JOURNAL OF APPLIED PHYSICS - Vol.110 No.9

<P>The electrical properties, presence of deep electron and hole traps and photoluminescence spectra were measured for undoped a-GaN films grown by metal-organic chemical vapor deposition (MOCVD) in a two-stage process using a high V/III ratio at the first stage and low V/III ratio at the second stage. Growth was performed on r-sapphire substrates with a high temperature GaN nucleation layer. The films showed a full width at half maximum of 450-470 arcseconds for the (11-20) x-ray rocking curve with little anisotropy with respect to the sample rotation around the growth direction. The stacking fault (SF) density determined by selective etching was similar to 5 x 10(4) cm(-1). The residual donor concentration was 10(14)-10(15) cm(-3), with a very low density (2.5 x 10(13) cm(-3)) of electron traps located at E-c - 0.6 eV, which are believed to be one of the major non-radiative recombination centers in nonpolar GaN. Consequently, the films showed a high intensity of bandedge luminescence with negligible contribution from defect bands associated with SFs. In contrast to previously studied nonpolar GaN films, the a-GaN layers showed a high concentration of gallium-vacancy-related acceptors near E-v + 1 eV and a strong yellow luminescence band, both indicating that growth conditions were effectively N-rich. a-AlGaN/GaN heterojunctions with thin heavily Si doped AlGaN barriers made on a-GaN substrates showed two-dimensional electron gas (2DEG) concentrations of 1.2 x 10(13) cm(-3), with 2DEG mobility of 80 cm(2)/Vs. Capacitance-voltage profiling of Schottky diodes on these HJs suggest that the 2DEG is fully depleted by the built-in voltage of the Schottky diode. (C)2011 American Institute of Physics. [doi: 10.1063/1.3658026]</P>

Pheophorbide a-mediated photodynamic therapy induces autophagy and apoptosis via the activation of MAPKs in human skin cancer cells

YOON, HYO-EUN,OH, SEONE-HEE,KIM, SOO-A,YOON, JUNG-HOON,AHN, SANG-GUN Spandidos Publications 2014 Oncology reports Vol.31 No.1

Pheophorbide a (Pa), a chlorophyll derivative, is a photosensitizer that can induce significant antitumor effects in several types of tumor cells. The present study investigated the mechanism of Pa-mediated photodynamic therapy (Pa-PDT) in the human skin cancer cell lines A431 and G361. PDT significantly inhibited the cell growth in a Pa-concentration-dependent manner. We observed increased expression of Beclin-1, LC3B and ATG5, which are markers of autophagy, after PDT treatment in A431 cells but not in G361 cells. In G361 cells, Pa-PDT strongly induced PARP cleavage and subsequent apoptosis, which was confirmed using Annexin V/Propidium iodide double staining. Pa-PDT predominantly exhibited its antitumor effects via activation of ERK1/2 and p38 in A431 and G361 cells, respectively. An in vivo study using the CAM xenograft model demonstrated that Pa-PDT strongly induced autophagy and apoptosis in A431-transplanted tumors and/or apoptosis in G361-transplanted tumors. These results may provide a basis for understanding the underlying mechanisms of Pa-PDT and for developing Pa-PDT as a therapy for skin cancer.

요로 감염증 환아에서 배뇨성 요로조영술을 시행하는 적절한 시기에 대한 평가

이정아,최제은,김성미,정진화,Lee Jung A,Choi Jae Eun,Kim Sung Mi,Jung Jin Hwa 대한소아신장학회 2001 Childhood kidney diseases Vol.5 No.2

목 적 : 요의 감염증 환아에서 방광 요관 역류는 흔히 발견되는 이상으로 대부분의 연구에서 요로 감염 3-6주 후 VCUG를 시행하는 것을 권유하고 있다. 하지만 검사를 하기 위해 기다리는 동안 만성 신질환으로 진행할 가능성이 있으며 추적 관찰에 실패하여 검사자체를 하지 못 하는 환아가 발생 할 수 있다. 따라서, 본 연구에서는 요로 감염 후 VCUG를 시행하는 시기가 요관 방광 역류의 빈도와 정도에 영향을 미치는지를 조사하였다. 대상 및 방법 : 1997년 3월부터 2000년 12월까지 요로 감염으로 메리놀병원 소아과에 내원한 환아 213명을 대상으로 후향적으로 조사하였다. 이들 환아를 요로 감염 진단 후 1주일 이내에 VCUG를 시행한 군(A군, 142명)과 1주일 이후에 VCUG를 시행한 군(B군, 71명)으로 나누어 각각을 비교하였다. 결 과 : A군의 $19\%$(27/142명), B군의 $18\%$(6/71명)에서 역류가 발견되었으며 통계학적으로 의미 있는 차이가 없었다(P=0.854). 하지만, 실제로 계획된 VCUG를 받은 환아는 A군 $100\%$, B군 $48\%$로 의미있은 차이가 있었으며(P<0.001), B군 환아에서 감염 후 VCUG를 받은 기간과 역류 정도에는 의미 있는 차이가 없었다(P=0.001). 결 론 : 본 연구의 결과에 따르면 요로 감염후 VCUG를 하는 기간과 역류의 빈도와 정도에는 차이가 없으므로 환아가 입원하고 있는 동안 VCUG를 시행하는 건이 더욱 바람직하며 이에 대한 보다 많은 연구가 필요하다고 생각한다. Purpose : Urinary tract infection is a common problem in children. To evaluate for reflux most authorities recommend a voiding cystourethrogram 3 to 6 weeks after the first urinary tract infection. But during the 3 to 6 weeks interval, patients may fail to show up for the scheduled VCUG and thus risk for loss of follow up. We analyzed patient's records to evaluate whether the timing of VCUG after UTI influenced the prevalence or severity of VUR. Methods : We retrospectively reviewed 213 children diagnosed with UTI from March 1997 to December 2000. These children were divided into 2 groups according to whether they had VCUG scheduled to be performed either within 1 weeks after the diagnosis of UTI (Group A) or later than 1 week after the diagnosis(Group B). We compared tile presence and severity of reflux in the 2 groups. Results : Reflux was present in $19\%$ of the patients studied within 1 week after UTI and in $18\%$ of those studied after 1 week. This difference was not statistically significant. Whereas $100\%$ of the scheduled VCUGs in the Group A were performed, only $48\%$ of those scheduled in the Group B were performed. This difference is statistically significant. Conclusion : Because there was no significant difference between the presence or severity of reflux and timing of VCUG after UTI, we suggest that a hospitalized patient with UTI should have VCUG performed before discharge. (J. Korean Sor Pediatr Nephrol 2001 ;5 : 176-81)

Di- and Triorganotin(IV) Complexes of Sulfur-containing Ylidenemalonates

Jung, Ok-Sang,Lee, Young-A,Hong, Jong-Ki,Jeong, Jong-Hwa,Sohn, Youn-Soo Korean Chemical Society 1993 Bulletin of the Korean Chemical Society Vol.14 No.6

Organotin(IV) complexes of ylidenemalonates $(R_xSn)_{x-1}(O_2C)_2C=C(SR')_2\;(R=n-C_4H_9,\;C_6H_5,\;cyclo-C_6H_{11},\;CH_3OOCCH_2CH_2;\;x=2,3;\;R'=CH_3,\;R_2'=-CHCH-,\;-CH_2CH_{2^-})$ have been synthesized and characterized by means of various spectroscopic methods. The X-ray crystal structure of $(Ph_3Sn)_2(O_2C)_2C=C(SCH_3)_2$ has been determined (Pi; a= 9.704(2) ${\AA}$, b= 14.412(1) ${\AA}$, c= 14.760(3) ${\AA}$, ${alpha}$=74.26(1)$^{\circ}$, ${beta}$=99.38(l)$^{\circ}$, ${\gamma}$=79.09(1)$^{\circ}$, $V= 1950.7(7){\AA}^3$) and refined to R= 0.045. The crystal structure discloses a discrete molecule with bidentate-like carboxylate ligand. For diorganotin analogues, the structures are discussed in terms of IR, $^1H-NMR,\;^{13}C-NMR$, and FAB mass spectrometry. The mass spectrum indicates that the diorganotin complexes of ylidenemalonates are dimeric.

Echinostome Infections in the Striped-Field Mouse, Apodemus agrarius, and the Ussuri White-Toothed Shrew, Crocidura lasiura, Caught Near the Demilitarized Zone, Gyeonggi-do (Province), Republic of Korea

Jong-Yil Chai,Jae-Hwan Park,Bong-Kwang Jung,Sang-Mee Guk,Jae-Lip Kim,Eun-Hee Shin,Terry A. Klein,Heung-Chul Kim,Sung-Tae Chong,Luck Ju Baek,Jin-Won Song 대한기생충학열대의학회 2009 The Korean Journal of Parasitology Vol.47 No.3

A total of 1,498 small mammals (rodents and insectivores), including Apodemus agrarius (n = 1,366), Crocidura lasiura (54), Mus musculus (32), Micronytus fortis (28), Eothenomys regulus (9), Micronys minutes (6), and Cricetulus triton (3), were live-trapped in Gyeonggi-do (Province) (Paju-si, Pocheon-gun, and Yeoncheon-gun) near the demilitarized zone (DMZ) from December 2004 to September 2005. A. agrarius was found to be infected with 3 species of echinostomes (Echinostoma hortense, Echinostoma cinetorchis, and Euparyphium murinum), while C. lasiura was infected with 1 species (Echinochasmus japonicas) of echinostome. Other mammals were free from echinostome infections. Total 16 E. hortense were detected in 7 (0.5%) mice, 9 E. cinetorchis from 5 (0.4%), and 3 E. murinum from 2 (0.1%) out of 1.366 A. agrarius examined. E. japonicus was found only in 1 (1.9%; total 3 specimens) C. lasiura. These results demonstrate that A. agrarius and C. lasiura, inhabiting near the DMZ of Gyeonggi-do serve as the natural definitive hosts for several species of echinostomes, although their infection rates are low. This is the first record of natural infections of A. agrarius with E. cinetorchis and C. lasiura with E. japonicus in the Republic of Korea.

Hairy Root Cultures of Taxus cuspidata for Enhanced Production of Paclitaxel

Jung A Kim,백광현,Young Mi Son,Sung Ho Son,Heungsop Shin 한국응용생명화학회 2009 Journal of Applied Biological Chemistry (J. Appl. Vol.52 No.2

Hairy root cultures were established by transforming seedlings of Taxus cuspidata Sieb. Et Zucc (Korean yew) using Agrobacterium rhizogenes. Initially, 107 lines of hairy roots were induced by infection with 3 strains of Agrobacterium (R1000, A4, and 15384), however, only three lines generated from the R1000 strain were stably grown on hormone-free media over 10 months of successive cultures. These lines were designated as RC11104, RC11105 and RC11106. The hairy root line RC 11106 was selected for further experiments for taxol production based on its growth properties. Upon methyl jasmonate treatment, the RC11106 line accumulated 52.5 mg/L of taxol over 2 weeks of incubation at a 20-L culture scale.

Energy Transfer from Ethidium to Cationic Porphyrins Mediated by DNA and Synthetic Polynucleotides at Low Binding Densities

Jung, Jin-A,Jeon, Sun-Hee,Han, Sung-Wook,Lee, Gil-Jun,Bae, In-Ho,Kim, Seog-K. Korean Chemical Society 2011 Bulletin of the Korean Chemical Society Vol.32 No.8

The fluorescence of ethidium bound to DNA, poly[d(A-T)$_2$], and poly[d(G-C)$_2$] at a [ethidium]/[DNA] ratio of 0.005 was quenched by porphyrins when both ethidium and the porphyrins simultaneously bound to the same polynucleotide. The quenching was tested using the "inner sphere" and the "Forster resonance energy transfer" (FRET) models, with the latter found to contribute, at least in part, to the quenching. Meso-tetrakis(N-methylpyridinium-4-yl)porphyrin (TMPyP) exhibited a higher quenching and FRET efficiency than cis-bis(N-methylpyridinium-4-yl)porphyrin (BMPyP) for all of the tested DNA and polynucleotides, demonstrating that energy transfer efficiency is affected by the number of positive charges of porphyrins.

Aquitalea denitrificans sp. nov., isolated from a Korean wetland.

Lee, Chang-Muk,Weon, Hang-Yeon,Kim, Yoo-Jeong,Son, Jung-A,Yoon, Sang-Hong,Koo, Bon-Sung,Kwon, Soon-Wo Society for General Microbiology 2009 International journal of systematic and evolutiona Vol.59 No.5

<P>A novel bacterium, designated strain 5YN1-3(T), was isolated from wetland peat collected from Yongneup, Korea. The bacterium was facultatively anaerobic, Gram-negative, yellow-coloured, rod-shaped, mesophilic and motile with one polar flagellum. The strain grew optimally at 30 degrees C, at pH 6.0-9.0 and with 0-1 % NaCl (w/v). 16S rRNA gene sequence analysis showed the highest similarity to the sequence from Aquitalea magnusonii TRO-001DR8(T), with 98.7 % sequence similarity. However, strain 5YN1-3(T) showed DNA-DNA relatedness of 43 % (40 % in a reciprocal experiment) with A. magnusonii LMG 23054(T). The strain contained summed feature 3 (iso-C(15 : 0) 2-OH and/or C(16 : 1)omega7c) and C(16 : 0) as major cellular fatty acids. On the basis of DNA-DNA relatedness and physiological and biochemical characterization, strain 5YN1-3(T) should be assigned to a novel species of the genus Aquitalea, for which the name Aquitalea denitrificans sp. nov. is proposed. The type strain is 5YN1-3(T) (=KACC 12729(T) =DSM 21300(T)).</P>