Controlled release of human growth hormone fused with a human hybrid Fc fragment through a nanoporous polymer membrane

Nanotechnology has been applied to the development of more effective and compatible drug delivery systems for therapeutic proteins. Human growth hormone (hGH) was fused with a hybrid Fc fragment containing partial Fc domains of human IgD and IgG(4) to produce a long-acting fusion protein. The fusion protein, hGH-hyFc, resulted in the increase of the hydrodynamic diameter (ca. 11 nm) compared with the diameter (ca. 5 nm) of the recombinant hGH. A diblock copolymer membrane with nanopores (average diameter of 14.3 nm) exhibited a constant release rate of hGH-hyFc. The hGH-hyFc protein released in a controlled manner for one month was found to trigger the phosphorylation of Janus kinase 2 (JAK2) in human B lymphocyte and to exhibit an almost identical circular dichroism spectrum to that of the original hGH-hyFc, suggesting that the released fusion protein should maintain the functional and structural integrity of hGH. Thus, the nanoporous release device could be a potential delivery system for the long-term controlled release of therapeutic proteins fused with the hybrid Fc fragment.X111313sciescopu

Hydrogen effects on nanoindentation behavior of metallic glass ribbons

Recently, metallic glass (MG) membranes that are permeable to hydrogen have gained interest due to the increasing importance of hydrogen separation in a number of applications, e.g., hydrogen-powered fuel cells. An important issue in the context of MG membranes is the hydrogen-induced embrittlement and efforts to understand the role played by hydrogen in the mechanical properties, especially yielding and plastic deformation behavior, of MGs are being made. In this study, therefore, an attempt was made by performing nanoindentation tests with cube-corner and spherical indenter tips on a series of Ni–Nb–Zr amorphous alloy ribbons to investigate the hydrogen effects on nanohardness and pop-in behavior (Figure 1). Weight gain measurements after hydrogen charging and thermal desorption spectroscopy (TDS) studies (Figure 2) were utilized to identify how the total hydrogen is partitioned into mobile and immobile parts. These, in turn, indicate the significant role of hydrogen mobility in the amorphous structure on the mechanical properties. In high-Zr alloys containing immobile H, both hardness (H) and shear yielding stress (τmax) increase significantly; while in low-Zr alloys having only mobile hydrogen, decrease in hardness and τmax were noted (Figure 1). The changes in shear transformation zone (STZ) volume, estimated through cumulative analysis of τmax, caused by hydrogen absorption were also found to depend on hydrogen mobility such that immobile hydrogen reduces the STZ volume while mobile hydrogen increases it. *This research was supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIP) (No. 2013R1A1A2A10058551)

Akt regulates the expression of MafK, synaptotagmin I, and syntenin-1, which play roles in neuronal function

<p>Abstract</p> <p>Background</p> <p>Akt regulates various cellular processes, including cell growth, survival, and metabolism. Recently, Akt's role in neurite outgrowth has also emerged. We thus aimed to identify neuronal function-related genes that are regulated by Akt.</p> <p>Methods</p> <p>We performed suppression subtractive hybridization on two previously established PC12 sublines, one of which overexpresses the wild-type (WT) form and the other, the dominant-negative (DN) form of Akt. These sublines respond differently to NGF's neuronal differentiation effect.</p> <p>Results</p> <p>A variety of genes was identified and could be classified into several functional groups, one of which was developmental processes. Two genes involved in neuronal differentiation and function were found in this group. v-Maf musculoaponeurotic fibrosarcoma oncogene homolog K (MafK) induces the neuronal differentiation of PC12 cells and immature telencephalon neurons, and synaptotagmin I (SytI) is essential for neurotransmitter release. Another gene, <it>syntenin-1 </it>(<it>Syn-1</it>) was also recognized in the same functional group into which <it>MafK </it>and <it>SytI </it>were classified. Syn-1 has been reported to promote the formation of membrane varicosities in neurons. Quantitative reverse transcription polymerase chain reaction analyses show that the transcript levels of these three genes were lower in PC12 (WT-Akt) cells than in parental PC12 and PC12 (DN-Akt) cells. Furthermore, treatment of PC12 (WT-Akt) cells with an Akt inhibitor resulted in the increase of the expression of these genes and the improvement of neurite outgrowth. These results indicate that dominant-negative or pharmacological inhibition of Akt increases the expression of <it>MafK</it>, <it>SytI</it>, and <it>Syn-1 </it>genes. Using lentiviral shRNA to knock down endogenous Syn-1 expression, we demonstrated that Syn-1 promotes an increase in the numbers of neurites and branches.</p> <p>Conclusions</p> <p>Taken together, these results indicate that Akt negatively regulates the expression of <it>MafK</it>, <it>SytI</it>, and <it>Syn-1 </it>genes that all participate in regulating neuronal integrity in some way or another.</p

Degradation of HER2/neu by ANT2 shRNA suppresses migration and invasiveness of breast cancer cells

Background: In breast cancer, the HER2/neu oncoprotein, which belongs to the epidermal growth factor receptor family, may trigger activation of the phosphoinositide-3 kinase (PI3K)/Akt pathway, which controls cell proliferation, survival, migration, and invasion. In this study, we examined the question of whether or not adenine nucleotide translocase 2 (ANT2) short hairpin RNA (shRNA)-mediated down-regulation of HER2/neu and inhibitory effects on the PI3K/Akt signaling pathway suppressed migration and invasiveness of breast cancer cells. Methods: We utilized an ANT2 vector-based RNA interference approach to inhibition of ANT2 expression, and the HER2/neu-overexpressing human breast cancer cell line, SK-BR3, was used throughout the study. Results: In this study, ANT2 shRNA decreased HER2/neu protein levels by promoting degradation of HER2/neu protein through dissociation from heat shock protein 90 (HSP90). As a result, ANT2 shRNA induced inhibitory effects on the PI3K/Akt signaling pathway. Inhibition of PI3K/Akt signaling by ANT2 shRNA caused down-regulation of membrane-type 1 matrix metalloproteinase (MT1-MMP) and vascular endothelial growth factor (VEGF) expression, decreased matrix metalloproteinase 2 (MMP2) and MMP9 activity, and suppressed migration and invasion of breast cancer cells. Conclusions: These results indicate that knock-down of ANT2 by shRNA down-regulates HER2/neu through suppression of HSP90`s function and inhibits the PI3K/Akt signaling pathway, resulting ultimately in suppressed migration and invasion of breast cancer cells.Wang S, 2009, MOL CANCER, V8, DOI 10.1186/1476-4598-8-81MAHMUT Y, 2009, CANC METASTASIS REV, V28, P15Jang JY, 2008, BREAST CANCER RES, V10, DOI 10.1186/bcr1857Ono M, 2006, CLIN CANCER RES, V12, P7242, DOI 10.1158/1078-0432.CCR-06-0646Stirling PC, 2006, NAT STRUCT MOL BIOL, V13, P865, DOI 10.1038/nsmb1153Le Bras M, 2006, CANCER RES, V66, P9143, DOI 10.1158/0008-5472.CAN-05-4407Scaltriti M, 2006, CLIN CANCER RES, V12, P5268, DOI 10.1158/1078-0432.CCR-06-1554ERIC I, 2006, AM J PHYSIOL-CELL PH, V291, P579Romond EH, 2005, NEW ENGL J MED, V353, P1673Piccart-Gebhart MJ, 2005, NEW ENGL J MED, V353, P1659Chevrollier A, 2005, J BIOENERG BIOMEMBR, V37, P307, DOI 10.1007/s10863-005-8642-5Meares GP, 2004, FEBS LETT, V574, P181, DOI 10.1016/j.febslet.2004.08.026Sreedhar AS, 2004, FEBS LETT, V562, P11Citri A, 2004, CELL CYCLE, V3, P51Luciakova K, 2003, J BIOL CHEM, V278, P30624, DOI 10.1074/jbc.M303530200Rao JS, 2003, NAT REV CANCER, V3, P489, DOI 10.1038/nrc1121Val JFF, 2002, CANCER GENET CYTOGEN, V138, P69GARCIARUIZ C, 2002, J BIOL CHEM, V277, P16396Slamon DJ, 2001, NEW ENGL J MED, V344, P783Prenzel N, 2001, ENDOCR-RELAT CANCER, V8, P11Braun S, 2001, CANCER RES, V61, P1890Xu WP, 2001, J BIOL CHEM, V276, P3702Sternlicht MD, 2001, ANNU REV CELL DEV BI, V17, P463Greenlee RT, 2001, CA-CANCER J CLIN, V51, P15Fang JM, 2000, P NATL ACAD SCI USA, V97, P3884Clynes RA, 2000, NAT MED, V6, P443Zhou BP, 2000, J BIOL CHEM, V275, P8027Menard S, 2000, J CELL PHYSIOL, V182, P150Cobleigh MA, 1999, J CLIN ONCOL, V17, P2639Pegram MD, 1998, J CLIN ONCOL, V16, P2659Fiore C, 1998, BIOCHIMIE, V80, P137WOLFGANG HS, 1998, J CELL BIOL, V143, P901Werb Z, 1997, CELL, V91, P439Baselga J, 1996, J CLIN ONCOL, V14, P737CORNELIUS LA, 1995, J INVEST DERMATOL, V105, P170HANEMAAIJER R, 1993, BIOCHEM J, V296, P803UNEMORI EN, 1990, J BIOL CHEM, V265, P445MIGNATTI P, 1989, J CELL BIOL, V108, P671SLAMON DJ, 1987, SCIENCE, V235, P177

Origin of Difference in the Reactivity of Aliphatic and Aromatic Guanidine-containing Pharmaceuticals Toward [18F]Fluorination: Coulombic Forces and Hydrogen Bonding

Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/151351/1/bkcs11842.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/151351/2/bkcs11842_am.pd

Phase Transition Behavior of Poly(N-isopropylacrylamide-co-N,Ndimethylaminopropylacrylamide) Hydrogels

The copolymer hydrogel of N-isopropylacrylamide (NIPAAm) and N,N-dimethylaminopropylacrylamide (DMAPAA) was synthesized by free radical copolymerization. The phase transition behavior of p(NIPAAmco-DMAPAA) hydrogels as a function of temperature and SDS concentration was studied. The p(NIPAAmco-DMAPAA) hydrogels exhibited larger swelling capacity than the homo p(NIPAAm) hydrogel. The phase transition temperature of p(NIPAAm-co-DMAPAA) hydrogels increased with an increase of DMAPAA content. In aqueous SDS solution, the swelling capacity of p(NIPAAm-co-DMAPAA) hydrogel decreased with an increase of SDS concentration. The phase transition temperature of p(NIPAAm-co-DMAPAA) hydrogels was found to be almost independent of the SDS concentration

Effects of dietary supplementation of a lipid-coated zinc oxide product on the fecal consistency, growth, and morphology of the intestinal mucosa of weanling pigs

Background Dietary supplementation of zinc oxide (ZnO) to 2000 to 4000 mg/kg is known to be effective for the prevention and treatment of post-weaning diarrhea in the pig. Such a pharmacological supplementation, however, can potentially result in environmental pollution of the heavy metal, because dietary ZnO is mostly excreted unabsorbed. Two experiments (Exp.) were performed in the present study to determine the effects of a lipid-coated ZnO supplement Shield Zn (SZ) compared with those of ZnO. Methods In Exp. 1, a total of 240 21-day-old weanling pigs were fed a diet supplemented with 100 mg Zn/kg as ZnO (ZnO-100), ZnO-2500, SZ-100, or SZ-200 in 24 pens for 14 days on a farm with its post-weaning pigs exhibiting a low incidence of diarrhea. Exp. 2 was performed using 192 24-day-old piglets as in Exp. 1 on a different farm, which exhibited a high incidence of diarrhea. Results In Exp. 1, fecal consistency (diarrhea) score (FCS) was less for the ZnO-2500 and SZ-200 groups than for the SZ-100 group (P < 0.05), with no difference between the SZ-100 and ZnO-100 groups. Both average daily gain (ADG) and gain:feed ratio were less for the SZ-200 group than for the ZnO-2500 group, with no difference between the ZnO-100 group and SZ-100 or SZ-200 group. The villus height (VH), crypt depth (CD), and VH:CD ratio of the intestinal mucosa were not influenced by the treatment. In Exp. 2, FCS was lowest for the ZnO-2500 group, with no difference among the other groups. However, neither the ADG nor gain:feed ratio was influenced by the treatment. Conclusion Results suggest that physiological SZ supplementation has less beneficial effects than pharmacological ZnO for the alleviation of diarrhea irrespective of its severity and for promoting growth without influencing their integrity of the intestinal mucosal structures with little advantage over physiological ZnO in weanling pigs with a small pen size.This work was supported by the Gyeongnam National University of Science and Technology Grant in 2016