Jack Liang - Academia.edu (original) (raw)
Papers by Jack Liang
A chemical investigation on the fruiting bodies of Fomitopsis pinicola led to the isolation and i... more A chemical investigation on the fruiting bodies of Fomitopsis pinicola led to the isolation and identification of twenty eight lanostane triterpenoids including eleven new compounds (1-11) and seventeen known analogues (12-28). Their structures were elucidated by extensive 1D, 2D NMR, and MS spectra. All isolates were tested for their anti-inflammatory activity, PTP1B inhibitory activity in vitro, and effect on glucose uptake in insulin-resistant HepG2 cells. Compounds 1, 4, 22, 23 and 27 inhibited the nitric oxide release from the LPS-induced RAW 264.7 cell assay with IC50 values in the range of 21.4-27.2 μM. Compounds 18, 22, 23, and 28 showed strong PTP1B inhibitory activity with IC50 values in the range of 20.5-29.9 μM, comparable to that of the positive control of oleanolic acid (15.0 μM). Compounds 18 and 22 were confirmed to be good competitive inhibitor of PTP1B by kinetic analysis. In addition, compounds 18, 22, and 28 were found to stimulat glucose uptake in the insulin-resistant HepG2 cells in the dose from 6.25 to 100 μM. These findings indicated the potential of F. pinicola in the development of functional food or medicine for the prevention and treatment of diabetes.
Aquaculture Nutrition, 2018
In aquaculture feeds, fishmeal (FM) has been considered the preferred protein source due to high ... more In aquaculture feeds, fishmeal (FM) has been considered the preferred protein source due to high crude protein content, ideal amino acid profile, high digestibility and palatability to fishes and so on (Kaushik & Seiliez, 2010; Riche, 2015). However, the decreasing marine fish stocks and the increasing price of FM are limitations for rapid development of aquaculture (Jahan, Watanabe, Kiron, & Satoh, 2003). Therefore, many other protein sources are being identified as replacements for FM in fish feeds, including plant protein sources (Hardy, 2010; Naylor et al., 2009). Low cost and abundance make plant proteins to be excellent alternatives for FM. Many studies have reported the partial or complete replacement of FM with plant proteins, such as soybean meal (SBM)
American journal of physiology. Endocrinology and metabolism, 2018
Insulin, the most potent anabolic hormone, is critical for somatic growth and metabolism in verte... more Insulin, the most potent anabolic hormone, is critical for somatic growth and metabolism in vertebrates. Type 2 diabetes, which is the primary cause of hyperglycemia, results from an inability of insulin to signal glycolysis and gluconeogenesis. Our previous study showed that double knockout of insulin receptor a ( insra) and b ( insrb) caused β-cell hyperplasia and lethality from 5 to 16 days postfertilization (dpf) (Yang BY, Zhai G, Gong YL, Su JZ, Han D, Yin Z, Xie SQ. Sci Bull (Beijing) 62: 486-492, 2017). In this study, we characterized the physiological roles of Insra and Insrb, in somatic growth and fueling metabolism, respectively. A high-carbohydrate diet was provided for insulin receptor knockout zebrafish from 60 to 120 dpf to investigate phenotype inducement and amplification. We observed hyperglycemia in both insra-/- fish and insrb-/- fish. Impaired growth hormone signaling, increased visceral adiposity, and fatty liver were detected in insrb-/- fish, which are phenoty...
Security and Communication Networks, 2016
Ubiquitous networks provide effective roaming services for mobile users (MUs). Through the worldw... more Ubiquitous networks provide effective roaming services for mobile users (MUs). Through the worldwide roaming technology, authorized MUs can avail ubiquitous network services. Important security issues to be considered in ubiquitous networks are authentication of roaming MUs and protection of privacy of MUs. However, because of the broadcast nature of wireless channel and resource limitations of terminals, providing efficient user authentication with privacy preservation is a challenging task. Very recently, Farash et al. proposed an authentication scheme with anonymity for consumer roaming in ubiquitous networks and claimed their scheme achieves all security requirements. In this paper, we show that the scheme of Farash et al. fails to achieve user anonymity and mutual authentication. Their scheme also fails to provide local password verification, and it has a faulty password change phase. Moreover, their scheme is vulnerable to replay, offline password guessing, and forgery attacks. To fix the security flaws of the scheme of Farash et al., we present an improved authentication scheme for accessing roaming service provided by ubiquitous networks. We then formally verify the security properties of our scheme by the widely-accepted pushbutton tool called Automated Validation of Internet Security Protocols and Applications. Security and performance analyses show that our scheme is more powerful, efficient, and secure when it is compared with existing schemes.
Biology of Reproduction, 2008
The present study was designed to investigate potential effects of arachidonic acid (ARA) on the ... more The present study was designed to investigate potential effects of arachidonic acid (ARA) on the reproductive physiology of female Atlantic cod (Gadus morhua L.). Two-year old Atlantic cod of both sexes were equally distributed into eight sea cages after completion of their first spawning in May 2005. Four experimental groups were established and fed diets with different levels of ARA corresponding to 0.5, 1, 2 and 4% of total fatty acid. Ovarian growth and development was documented every month. Fatty acid composition was analysed in ovaries, liver and plasma at the beginning of the experiment, one month prior to spawning, and in spent fish, one month after spawning was completed. Plasma concentrations of estradiol-17b, testosterone and vitellogenin, and ovarian gene transcript levels of steroidogenic acute regulatory protein (star), P450aromatase (cyp19a1a) and 20bhydroxy steroid dehydrogenase (20bhsd/cbr1) were monitored every month in fish fed the experimental diets and related to oocyte stage. Potential fecundity was calculated based on ovarian samples taken one month before onset of spawning. Ovarian and plasma ARA levels were highly correlated to dietary ARA levels. There was a net accumulation of ARA compared to other essential fatty acids in ovarian tissue that was reflected in a decrease in EPA:ARA ratio. Plasma concentrations of vitellogenin, estradiol-17b and testosterone and key gene transcript levels were affected by dietary ARA and stage of maturation. The results show that ARA has a significant influence on the reproductive physiology of female Atlantic cod.
European Journal of Cancer, 2015
Liang's interpretation of MacKenzie's "Lost River" and "Saskatchewan"... more Liang's interpretation of MacKenzie's "Lost River" and "Saskatchewan" series of paintings focuses on issues concerning cultural identity and place. He suggests the works deconstruct historical notions of the North and demythologize received ideas about the Canadian landscape. Biographical notes. 31 bibl. ref.
The present disclosure provides ketoreductase enzymes that have been engineered with wild-type ke... more The present disclosure provides ketoreductase enzymes that have been engineered with wild-type ketoreductase enzyme and improved properties compared to naturally occurring. Polynucleotides encoding the engineered ketoreductase enzyme, the host cell capable of expressing the engineered ketoreductase enzyme, and methods of synthesizing the various chiral compounds using the engineered ketoreductase enzyme also provided. In one aspect, the present disclosure is 2- [3- [3- [2- (7-chloro-2-quinolinyl) ethenyl] phenyl] -3-oxopropyl] benzoic acid methyl ester ( "substrate") ( S, E) - can be reduced to methyl 2- (3- (3- (2- (7-chloro-2-yl) vinyl) phenyl) -3-hydroxypropyl) benzoate ( "product") or to provide a ketoreductase polypeptide capable of converting.
A bioenergetic model was constructed to estimate growth potential, feed requirement, and waste ou... more A bioenergetic model was constructed to estimate growth potential, feed requirement, and waste output in Chinese longsnout catfish (Leiocassis longirostris Günther). The bioenergetic model was driven by three variables: ration level, fish size, and water temperature, using experimentally-derived values. Thus, the feed requirement model was based on accurate simulated growth potential. In experiment 1, the energy budget was investigated at five ration levels: starvation, 0.8%, 1.6%, or 2.4% of the fish body weight per day, and apparent satiation. In experiment 2, additional parameters were determined in four rearing temperatures (20°C, 24°C, 28°C, and 32°C) using fish of 17, 36, 67, and 303 g. In experiment 3, values were estimated using the bioenergetic model, then validated in an independent 104-day experiment in which triplicate groups of fish were fed one of three rations based on the bioenergetic model: maximum, optimum, or 80% of the optimum (g/individual/day). No obvious bias ...
Organic Process Research & Development, 2010
By leveraging enzyme evolution technologies, the enantioselectivity of a KetoREDuctase (KRED) tow... more By leveraging enzyme evolution technologies, the enantioselectivity of a KetoREDuctase (KRED) towards the nearly spatially symmetrical ketone tetrahydrothiophene-3-one was increased from 63% ee to 99.3% ee. The biocatalytic process gives (R)-tetrahydrothiophene-3-ol in one step from a commodity chemical and supplants the original multistep hazardous processes starting from the chiral pool. The biocatalytic process has been successfully scaled to 100 kg.
Challenges, Approaches and Solutions, 2010
Whittall/Practical Methods for Biocatalysis and Biotransformations 2, 2012
ABSTRACT
Proceedings of the National Academy of Sciences of the United States of America, Jan 18, 2014
Carbonic anhydrase (CA) is one of nature's fastest enzymes and can dramatically improve the e... more Carbonic anhydrase (CA) is one of nature's fastest enzymes and can dramatically improve the economics of carbon capture under demanding environments such as coal-fired power plants. The use of CA to accelerate carbon capture is limited by the enzyme's sensitivity to the harsh process conditions. Using directed evolution, the properties of a β-class CA from Desulfovibrio vulgaris were dramatically enhanced. Iterative rounds of library design, library generation, and high-throughput screening identified highly stable CA variants that tolerate temperatures of up to 107 °C in the presence of 4.2 M alkaline amine solvent at pH…
A chemical investigation on the fruiting bodies of Fomitopsis pinicola led to the isolation and i... more A chemical investigation on the fruiting bodies of Fomitopsis pinicola led to the isolation and identification of twenty eight lanostane triterpenoids including eleven new compounds (1-11) and seventeen known analogues (12-28). Their structures were elucidated by extensive 1D, 2D NMR, and MS spectra. All isolates were tested for their anti-inflammatory activity, PTP1B inhibitory activity in vitro, and effect on glucose uptake in insulin-resistant HepG2 cells. Compounds 1, 4, 22, 23 and 27 inhibited the nitric oxide release from the LPS-induced RAW 264.7 cell assay with IC50 values in the range of 21.4-27.2 μM. Compounds 18, 22, 23, and 28 showed strong PTP1B inhibitory activity with IC50 values in the range of 20.5-29.9 μM, comparable to that of the positive control of oleanolic acid (15.0 μM). Compounds 18 and 22 were confirmed to be good competitive inhibitor of PTP1B by kinetic analysis. In addition, compounds 18, 22, and 28 were found to stimulat glucose uptake in the insulin-resistant HepG2 cells in the dose from 6.25 to 100 μM. These findings indicated the potential of F. pinicola in the development of functional food or medicine for the prevention and treatment of diabetes.
Aquaculture Nutrition, 2018
In aquaculture feeds, fishmeal (FM) has been considered the preferred protein source due to high ... more In aquaculture feeds, fishmeal (FM) has been considered the preferred protein source due to high crude protein content, ideal amino acid profile, high digestibility and palatability to fishes and so on (Kaushik & Seiliez, 2010; Riche, 2015). However, the decreasing marine fish stocks and the increasing price of FM are limitations for rapid development of aquaculture (Jahan, Watanabe, Kiron, & Satoh, 2003). Therefore, many other protein sources are being identified as replacements for FM in fish feeds, including plant protein sources (Hardy, 2010; Naylor et al., 2009). Low cost and abundance make plant proteins to be excellent alternatives for FM. Many studies have reported the partial or complete replacement of FM with plant proteins, such as soybean meal (SBM)
American journal of physiology. Endocrinology and metabolism, 2018
Insulin, the most potent anabolic hormone, is critical for somatic growth and metabolism in verte... more Insulin, the most potent anabolic hormone, is critical for somatic growth and metabolism in vertebrates. Type 2 diabetes, which is the primary cause of hyperglycemia, results from an inability of insulin to signal glycolysis and gluconeogenesis. Our previous study showed that double knockout of insulin receptor a ( insra) and b ( insrb) caused β-cell hyperplasia and lethality from 5 to 16 days postfertilization (dpf) (Yang BY, Zhai G, Gong YL, Su JZ, Han D, Yin Z, Xie SQ. Sci Bull (Beijing) 62: 486-492, 2017). In this study, we characterized the physiological roles of Insra and Insrb, in somatic growth and fueling metabolism, respectively. A high-carbohydrate diet was provided for insulin receptor knockout zebrafish from 60 to 120 dpf to investigate phenotype inducement and amplification. We observed hyperglycemia in both insra-/- fish and insrb-/- fish. Impaired growth hormone signaling, increased visceral adiposity, and fatty liver were detected in insrb-/- fish, which are phenoty...
Security and Communication Networks, 2016
Ubiquitous networks provide effective roaming services for mobile users (MUs). Through the worldw... more Ubiquitous networks provide effective roaming services for mobile users (MUs). Through the worldwide roaming technology, authorized MUs can avail ubiquitous network services. Important security issues to be considered in ubiquitous networks are authentication of roaming MUs and protection of privacy of MUs. However, because of the broadcast nature of wireless channel and resource limitations of terminals, providing efficient user authentication with privacy preservation is a challenging task. Very recently, Farash et al. proposed an authentication scheme with anonymity for consumer roaming in ubiquitous networks and claimed their scheme achieves all security requirements. In this paper, we show that the scheme of Farash et al. fails to achieve user anonymity and mutual authentication. Their scheme also fails to provide local password verification, and it has a faulty password change phase. Moreover, their scheme is vulnerable to replay, offline password guessing, and forgery attacks. To fix the security flaws of the scheme of Farash et al., we present an improved authentication scheme for accessing roaming service provided by ubiquitous networks. We then formally verify the security properties of our scheme by the widely-accepted pushbutton tool called Automated Validation of Internet Security Protocols and Applications. Security and performance analyses show that our scheme is more powerful, efficient, and secure when it is compared with existing schemes.
Biology of Reproduction, 2008
The present study was designed to investigate potential effects of arachidonic acid (ARA) on the ... more The present study was designed to investigate potential effects of arachidonic acid (ARA) on the reproductive physiology of female Atlantic cod (Gadus morhua L.). Two-year old Atlantic cod of both sexes were equally distributed into eight sea cages after completion of their first spawning in May 2005. Four experimental groups were established and fed diets with different levels of ARA corresponding to 0.5, 1, 2 and 4% of total fatty acid. Ovarian growth and development was documented every month. Fatty acid composition was analysed in ovaries, liver and plasma at the beginning of the experiment, one month prior to spawning, and in spent fish, one month after spawning was completed. Plasma concentrations of estradiol-17b, testosterone and vitellogenin, and ovarian gene transcript levels of steroidogenic acute regulatory protein (star), P450aromatase (cyp19a1a) and 20bhydroxy steroid dehydrogenase (20bhsd/cbr1) were monitored every month in fish fed the experimental diets and related to oocyte stage. Potential fecundity was calculated based on ovarian samples taken one month before onset of spawning. Ovarian and plasma ARA levels were highly correlated to dietary ARA levels. There was a net accumulation of ARA compared to other essential fatty acids in ovarian tissue that was reflected in a decrease in EPA:ARA ratio. Plasma concentrations of vitellogenin, estradiol-17b and testosterone and key gene transcript levels were affected by dietary ARA and stage of maturation. The results show that ARA has a significant influence on the reproductive physiology of female Atlantic cod.
European Journal of Cancer, 2015
Liang's interpretation of MacKenzie's "Lost River" and "Saskatchewan"... more Liang's interpretation of MacKenzie's "Lost River" and "Saskatchewan" series of paintings focuses on issues concerning cultural identity and place. He suggests the works deconstruct historical notions of the North and demythologize received ideas about the Canadian landscape. Biographical notes. 31 bibl. ref.
The present disclosure provides ketoreductase enzymes that have been engineered with wild-type ke... more The present disclosure provides ketoreductase enzymes that have been engineered with wild-type ketoreductase enzyme and improved properties compared to naturally occurring. Polynucleotides encoding the engineered ketoreductase enzyme, the host cell capable of expressing the engineered ketoreductase enzyme, and methods of synthesizing the various chiral compounds using the engineered ketoreductase enzyme also provided. In one aspect, the present disclosure is 2- [3- [3- [2- (7-chloro-2-quinolinyl) ethenyl] phenyl] -3-oxopropyl] benzoic acid methyl ester ( "substrate") ( S, E) - can be reduced to methyl 2- (3- (3- (2- (7-chloro-2-yl) vinyl) phenyl) -3-hydroxypropyl) benzoate ( "product") or to provide a ketoreductase polypeptide capable of converting.
A bioenergetic model was constructed to estimate growth potential, feed requirement, and waste ou... more A bioenergetic model was constructed to estimate growth potential, feed requirement, and waste output in Chinese longsnout catfish (Leiocassis longirostris Günther). The bioenergetic model was driven by three variables: ration level, fish size, and water temperature, using experimentally-derived values. Thus, the feed requirement model was based on accurate simulated growth potential. In experiment 1, the energy budget was investigated at five ration levels: starvation, 0.8%, 1.6%, or 2.4% of the fish body weight per day, and apparent satiation. In experiment 2, additional parameters were determined in four rearing temperatures (20°C, 24°C, 28°C, and 32°C) using fish of 17, 36, 67, and 303 g. In experiment 3, values were estimated using the bioenergetic model, then validated in an independent 104-day experiment in which triplicate groups of fish were fed one of three rations based on the bioenergetic model: maximum, optimum, or 80% of the optimum (g/individual/day). No obvious bias ...
Organic Process Research & Development, 2010
By leveraging enzyme evolution technologies, the enantioselectivity of a KetoREDuctase (KRED) tow... more By leveraging enzyme evolution technologies, the enantioselectivity of a KetoREDuctase (KRED) towards the nearly spatially symmetrical ketone tetrahydrothiophene-3-one was increased from 63% ee to 99.3% ee. The biocatalytic process gives (R)-tetrahydrothiophene-3-ol in one step from a commodity chemical and supplants the original multistep hazardous processes starting from the chiral pool. The biocatalytic process has been successfully scaled to 100 kg.
Challenges, Approaches and Solutions, 2010
Whittall/Practical Methods for Biocatalysis and Biotransformations 2, 2012
ABSTRACT
Proceedings of the National Academy of Sciences of the United States of America, Jan 18, 2014
Carbonic anhydrase (CA) is one of nature's fastest enzymes and can dramatically improve the e... more Carbonic anhydrase (CA) is one of nature's fastest enzymes and can dramatically improve the economics of carbon capture under demanding environments such as coal-fired power plants. The use of CA to accelerate carbon capture is limited by the enzyme's sensitivity to the harsh process conditions. Using directed evolution, the properties of a β-class CA from Desulfovibrio vulgaris were dramatically enhanced. Iterative rounds of library design, library generation, and high-throughput screening identified highly stable CA variants that tolerate temperatures of up to 107 °C in the presence of 4.2 M alkaline amine solvent at pH…