7 research outputs found
The Performance of a Diesel Engine Fueled with Diesel Oil, Biodiesel and Preheated Coconut Oil
Fossil fuel crisis and depletion, environmental pollution and ever-increase in vehicle and transportation means have renewed the scientist\u27s interest in the world in order to look for potential alternative fuels, which are attractive such as biodiesel, bioethanol, DME and vegetable oils. Inedible vegetable oils such as coconut oil, Jatropha oil, linseed oil or animal fat are full of potential for using directly or manufacturing biodiesel. This work is carried out in order to study the four stroke diesel engine D240 performance characteristics fueled with preheated pure coconut oil (PCO), Jatropha oil methyl ester (JOME) and compare with diesel oil (DO). The test diesel engine performance such as power (Ne), torque (Me), specific fuel consumption (ge) and thermal efficiency (ηe) is determined, calculated and evaluated while using JOME, preheated PCO and compared to DO. The results show that, power (Ne), torque (Me) and thermal efficiency (ηe) while engine is fueled with JOME and PCO are lower, otherwise specific fuel consumption (ge) is higher than those of diesel fuel, the test engine performance are gained the best for JOME and PCO100. Keywords: biofuel, biodiesel, preheated vegetable oils, engine performance, efficiency, specific fuel consumption.Article History: Received Dec 9, 2016; Received in revised form January 28, 2017; Accepted February 4, 2017; Available onlineHow to Cite This Article: Hoang, T.A and Le,V. V. (2017). The Performance of A Diesel Engine Fueled With Diesel Oil, Biodiesel and Preheated Coconut Oil. International Journal of Renewable Energy Development, 6(1), 1-7.http://dx.doi.org/10.14710/ijred.6.1.1-
A smart tumor targeting peptide–drug conjugate, pHLIP-SS-DOX: synthesis and cellular uptake on MCF-7 and MCF-7/Adr cells
<p>Doxorubicin (DOX) is a potent anticancer drug for the treatment of tumors, but the poor specificity and multi-drug resistance (MDR) on tumor cells have restricted its application. Here, a pH and reduction-responsive peptide–drug conjugate (PDC), pHLIP-SS-DOX, was synthesized to overcome these drawbacks. pH low insertion peptide (pHLIP) is a cell penetrating peptide (CPP) with pH-dependent transmembrane ability. And because of the unique cell membrane insertion pattern, it might reverse the MDR. The cellular uptake study showed that on both drug-sensitive MCF-7 and drug-resistant MCF-7/Adr cells, pHLIP-SS-DOX obviously facilitated the uptake of DOX at pH 6.0 and the uptake level on MCF-7/Adr cells was similar with that on MCF-7 cells, indicating that pHLIP-SS-DOX had the ability to target acidic tumor cells and reverse MDR. <i>In vitro</i> cytotoxicity study mediated by GSH-OEt demonstrated that the cytotoxic effect of pHLIP-SS-DOX was reduction responsive, with obvious cytotoxicity at pH 6.0; while it had poor cytotoxicity at pH 7.4, no matter with or without GSH-OEt pretreatment. This illustrated that pHLIP could deliver DOX into tumor cells with acidic microenvironment specifically and could not deliver drugs into normal cells with neutral microenvironment. In summary, pHLIP-SS-DOX is a promising strategy to target drugs to tumors and provides a possibility to overcome MDR.</p
Localized co-delivery of collagenase and trastuzumab by thermosensitive hydrogels for enhanced antitumor efficacy in human breast xenograft
<p>Modulation of the collagen-rich extracellular matrix (ECM) in solid tumors by the treatment with collagenase has been proved effective in enhancement of the interstitial transport and antitumor efficacy of antibodies. We, therefore, developed a PLGA-PEG-PLGA polymer-based thermosensitive hydrogel, which incorporated a HER2-targeted monoclonal antibody trastuzumab and collagenase (Col/Tra/Gel) for peritumoral administration. HER2-positvie BT474 tumor-bearing mice were selected as a model. The Col/Tra/Gel showed the continuous and biphasic release of protein drugs for 9 days <i>in vitro</i>. NIR imaging studies demonstrated a long-term retention of Col/Tra/Gel hydrogel in the peritumoral area for over 20 days. Treatment with Col/Tra/Gel reduced the collagen density and enhanced apoptotic cell death in tumor tissue, resulting in superior treatments with increased efficacy and reduced toxicity compared with other control groups. Moreover, a quarter-dose of Col/Tra/Gel exhibited a better antitumor efficacy than that of intravenous injection of clinical trastuzumab formulation. This localized co-delivery system offers a potential strategy for the modulation of dense ECM and enhancement of antibody efficacy.</p
Intestinal Mucin Induces More Endocytosis but Less Transcytosis of Nanoparticles across Enterocytes by Triggering Nanoclustering and Strengthening the Retrograde Pathway
Mucus, which is secreted by the goblet
cells of enterocytes, constitutes
the first obstacle encountered for the intestinal absorption of nanomedicines.
For decades, mucus has simply been regarded as a physical barrier
that hinders the permeation and absorption of drugs, because of its
high viscosity and reticular structure, whereas the interaction of
mucus ingredients with nanomedicines is usually neglected. It is unclear
whether glycoproteins, as the main components of mucus, interact with
nanomedicines. We also do not know how the potential interaction affects
the subsequent transportation of nanomedicines through the intestinal
epithelium. In this study, mucin as the key element of mucus was investigated
to characterize the interaction of nanomedicines with mucus. PEG-modified
gold nanoparticles (PGNPs) were fabricated as model nanoparticles.
Mucin was found to adhere to the nanoparticle surface to form a corona
structure and induce the clustering of PGNPs by joining particles
together, demonstrating the interaction between mucin and PGNPs. In
addition, two intestinal epithelia, Caco-2 (non- mucus secretion)
and HT-29 (high mucus secretion), were compared to evaluate the influence
of mucin on the cellular interaction of PGNPs. Amazingly, mucin altered
the trafficking characteristic of PGNPs in intestinal epithelium.
Both in vitro and in vivo investigations demonstrated more nanoparticles
being internalized by cells due to the mucin coverage. However, mucin
induced a significant reduction in the transcytosis of PGNPs across
epithelial monolayers. The mechanism exploration further revealed
that the “more endocytosis but less transcytosis (MELT)”
effect was mainly attributed to the strengthened retrograde pathway
in which more PGNPs were transported to Golgi apparatus and exocytosed
back to the apical but not the basolateral side of the epithelial
monolayers. The “MELT” effect endowed mucin with duality
in the nanoparticle transportation. Therefore, the rational regulation
based on the “MELT” effect will provide new insight
into overcoming the mucus obstacle as a barrier and enhancing the
oral absorption rate of nanomedicines
Intestinal Mucin Induces More Endocytosis but Less Transcytosis of Nanoparticles across Enterocytes by Triggering Nanoclustering and Strengthening the Retrograde Pathway
Mucus, which is secreted by the goblet
cells of enterocytes, constitutes
the first obstacle encountered for the intestinal absorption of nanomedicines.
For decades, mucus has simply been regarded as a physical barrier
that hinders the permeation and absorption of drugs, because of its
high viscosity and reticular structure, whereas the interaction of
mucus ingredients with nanomedicines is usually neglected. It is unclear
whether glycoproteins, as the main components of mucus, interact with
nanomedicines. We also do not know how the potential interaction affects
the subsequent transportation of nanomedicines through the intestinal
epithelium. In this study, mucin as the key element of mucus was investigated
to characterize the interaction of nanomedicines with mucus. PEG-modified
gold nanoparticles (PGNPs) were fabricated as model nanoparticles.
Mucin was found to adhere to the nanoparticle surface to form a corona
structure and induce the clustering of PGNPs by joining particles
together, demonstrating the interaction between mucin and PGNPs. In
addition, two intestinal epithelia, Caco-2 (non- mucus secretion)
and HT-29 (high mucus secretion), were compared to evaluate the influence
of mucin on the cellular interaction of PGNPs. Amazingly, mucin altered
the trafficking characteristic of PGNPs in intestinal epithelium.
Both in vitro and in vivo investigations demonstrated more nanoparticles
being internalized by cells due to the mucin coverage. However, mucin
induced a significant reduction in the transcytosis of PGNPs across
epithelial monolayers. The mechanism exploration further revealed
that the “more endocytosis but less transcytosis (MELT)”
effect was mainly attributed to the strengthened retrograde pathway
in which more PGNPs were transported to Golgi apparatus and exocytosed
back to the apical but not the basolateral side of the epithelial
monolayers. The “MELT” effect endowed mucin with duality
in the nanoparticle transportation. Therefore, the rational regulation
based on the “MELT” effect will provide new insight
into overcoming the mucus obstacle as a barrier and enhancing the
oral absorption rate of nanomedicines
Intestinal Mucin Induces More Endocytosis but Less Transcytosis of Nanoparticles across Enterocytes by Triggering Nanoclustering and Strengthening the Retrograde Pathway
Mucus, which is secreted by the goblet
cells of enterocytes, constitutes
the first obstacle encountered for the intestinal absorption of nanomedicines.
For decades, mucus has simply been regarded as a physical barrier
that hinders the permeation and absorption of drugs, because of its
high viscosity and reticular structure, whereas the interaction of
mucus ingredients with nanomedicines is usually neglected. It is unclear
whether glycoproteins, as the main components of mucus, interact with
nanomedicines. We also do not know how the potential interaction affects
the subsequent transportation of nanomedicines through the intestinal
epithelium. In this study, mucin as the key element of mucus was investigated
to characterize the interaction of nanomedicines with mucus. PEG-modified
gold nanoparticles (PGNPs) were fabricated as model nanoparticles.
Mucin was found to adhere to the nanoparticle surface to form a corona
structure and induce the clustering of PGNPs by joining particles
together, demonstrating the interaction between mucin and PGNPs. In
addition, two intestinal epithelia, Caco-2 (non- mucus secretion)
and HT-29 (high mucus secretion), were compared to evaluate the influence
of mucin on the cellular interaction of PGNPs. Amazingly, mucin altered
the trafficking characteristic of PGNPs in intestinal epithelium.
Both in vitro and in vivo investigations demonstrated more nanoparticles
being internalized by cells due to the mucin coverage. However, mucin
induced a significant reduction in the transcytosis of PGNPs across
epithelial monolayers. The mechanism exploration further revealed
that the “more endocytosis but less transcytosis (MELT)”
effect was mainly attributed to the strengthened retrograde pathway
in which more PGNPs were transported to Golgi apparatus and exocytosed
back to the apical but not the basolateral side of the epithelial
monolayers. The “MELT” effect endowed mucin with duality
in the nanoparticle transportation. Therefore, the rational regulation
based on the “MELT” effect will provide new insight
into overcoming the mucus obstacle as a barrier and enhancing the
oral absorption rate of nanomedicines
Intestinal Mucin Induces More Endocytosis but Less Transcytosis of Nanoparticles across Enterocytes by Triggering Nanoclustering and Strengthening the Retrograde Pathway
Mucus, which is secreted by the goblet
cells of enterocytes, constitutes
the first obstacle encountered for the intestinal absorption of nanomedicines.
For decades, mucus has simply been regarded as a physical barrier
that hinders the permeation and absorption of drugs, because of its
high viscosity and reticular structure, whereas the interaction of
mucus ingredients with nanomedicines is usually neglected. It is unclear
whether glycoproteins, as the main components of mucus, interact with
nanomedicines. We also do not know how the potential interaction affects
the subsequent transportation of nanomedicines through the intestinal
epithelium. In this study, mucin as the key element of mucus was investigated
to characterize the interaction of nanomedicines with mucus. PEG-modified
gold nanoparticles (PGNPs) were fabricated as model nanoparticles.
Mucin was found to adhere to the nanoparticle surface to form a corona
structure and induce the clustering of PGNPs by joining particles
together, demonstrating the interaction between mucin and PGNPs. In
addition, two intestinal epithelia, Caco-2 (non- mucus secretion)
and HT-29 (high mucus secretion), were compared to evaluate the influence
of mucin on the cellular interaction of PGNPs. Amazingly, mucin altered
the trafficking characteristic of PGNPs in intestinal epithelium.
Both in vitro and in vivo investigations demonstrated more nanoparticles
being internalized by cells due to the mucin coverage. However, mucin
induced a significant reduction in the transcytosis of PGNPs across
epithelial monolayers. The mechanism exploration further revealed
that the “more endocytosis but less transcytosis (MELT)”
effect was mainly attributed to the strengthened retrograde pathway
in which more PGNPs were transported to Golgi apparatus and exocytosed
back to the apical but not the basolateral side of the epithelial
monolayers. The “MELT” effect endowed mucin with duality
in the nanoparticle transportation. Therefore, the rational regulation
based on the “MELT” effect will provide new insight
into overcoming the mucus obstacle as a barrier and enhancing the
oral absorption rate of nanomedicines