A novel and efficient heterogeneous catalyst has been developed by immobilization of palladium on... more A novel and efficient heterogeneous catalyst has been developed by immobilization of palladium on the chlorinated polyvinylchloride nanofiber mats.
The relative ozonation rate constants for p-phenylenediamines have been estimated from the linear... more The relative ozonation rate constants for p-phenylenediamines have been estimated from the linear correlation of the ozonation rate constants with the ionization potentials (Figure 1). The efficient antiozonants were found to have relatively lower ionization potentials, but not too low to react with the atmospheric molecular oxygen. The bond dissociation enthalpies (BDEs) of the N—H bonds of p-aminodiphenylamine and related derivatives were found to be about 80 kcal/mol, suggesting that the p-aminodiphenylamines are not only efficient antiozonants, but are also efficient antioxidants. Efficient antiozonants should also be efficient antioxidants to quench the reactive radical intermediates formed during the degradation.
The equilibrium acidities (p K as) of six families of remotely substituted benzyl onium salts (ie... more The equilibrium acidities (p K as) of six families of remotely substituted benzyl onium salts (ie, 4-G-C6H4CH2-E+⊙ Br-, where E+= Ph3P+, Ph2PO, Et3N+, Me2S+, Me2Se+, and Bu2Te+ and G= H, Me, CF3, CO2Me, CN, and NO2), one family of α-E+ substituted ...
Supplemental material, EMS896708 Supplemental Material for Insight into nucleophilic fragmentatio... more Supplemental material, EMS896708 Supplemental Material for Insight into nucleophilic fragmentation mechanisms by glutamic acid side chain in singly protonated glutathione and related peptidyl ions by Liqun Fan, Jinhu Wang, Chunli Liu, Tiesheng Shi, Xian-Man Zhang, Yanqing Xia, Lina Fan and Yang Liu in European Journal of Mass Spectrometry
5) was also found to shift the proton resonances of the external homocarnosine from that of the i... more 5) was also found to shift the proton resonances of the external homocarnosine from that of the internal homocarnosine as shown in Figure 2. The chemical shift change caused by addition of TmDOTP 5was linearly correlated with the shift reagent concentration with a slope of 0.133 ppm/mM (R 2 =0.998), indicating that 0.3 mM of TmDOTP 5was sufficient to resolve the two resonances without significant line broadening. The encapsulation efficiencies determined directly from the separated internal and external proton resonance integrations are summarized in Table 1 for the DPPC liposomes prepared by extrusion through 50, 200 and 1000 nm polycarbonate membranes. Examination of Table 1 showed that the encapsulation efficiency increases as the liposome size increases, and the results from the two different experimental approaches were remarkably consistent with each other. Table 1. Encapsulation Efficiencies a a The total lipid concentration was 51 mg/ml. b The pore size of the polycarbonate ...
Caloric restriction without malnutrition (CR) is the most robust and reproducible way to extend l... more Caloric restriction without malnutrition (CR) is the most robust and reproducible way to extend lifespan and delay the onset of age-related diseases, such as hepatic steatosis, insulin resistance and type 2 diabetes (T2D). Unfortunately, the strict dietary regime necessary to achieve the beneficial effects of CR limits the use of this treatment to retard aging and disease in humans and new therapies are required. In this regard, our lab has recently developed a new class of therapeutic agents that are designed to safely promote liver-targeted mitochondrial uncoupling with a wide-therapeutic index. Our second-generation compound in this class is controlled-release mitochondrial protonophore (CRMP) that is functionally liver-targeted and promotes oxidation of hepatic triglycerides by promoting a subtle sustained increase in hepatic mitochondrial inefficiency. While we have previously demonstrated that this agent safely reverses hypertriglyceridemia, fatty liver, and hepatic inflammation/fibrosis in young-adult diet-induced rodent models of obesity, its effects on healthspan and lifespan remain to be determined. Here, we evaluated the impact of CRMP on hepatic steatosis and insulin action in aged 74-week-old male C57BL/6J mice fed a high-fat diet (HFD; 45% fat) for 12 weeks. Specifically, we demonstrate that CRMP treatment significantly reduced liver triglycerides, diacylglycerols, and transaminase levels independently of changes in body weight, whole-body energy expenditure or food intake. Additionally, long-term CRMP treatment reduced fasting plasma glucose concentrations (P Disclosure L. Goedeke: None. J. Camporez: None. A. Nasiri: None. Y. Wang: None. X. Zhang: None. G.I. Shulman: Advisory Panel; Self; AstraZeneca, Janssen Research & Development, Merck & Co., Inc., Novo Nordisk Inc.. Research Support; Self; Gilead Sciences, Inc..
Aluminum tris(8-hydroxyquinoline) (Alq3) is presently considered one of the most reliable electro... more Aluminum tris(8-hydroxyquinoline) (Alq3) is presently considered one of the most reliable electron transporting and emitting materials for molecular-based organic light emitting diodes (OLEDs). This paper discusses the effects of sample morphology on the hydrolysis and photoluminescence response of Alq3. The evolution of 8-hydroxyquinoline (8-Hq), a volatile byproduct of the hydrolysis of Alq3, was quantified using gas chromatography/mass spectroscopy (GC/MS) analysis on samples of different morphology. Annealed (more crystalline) samples exhibited greater chemical stability than freshly sublimed films, at the expense of photoluminescence efficiency. These phenomena are discussed with respect to possible failure mechanisms that Alq3-based OLEDs might undergo during prolonged operation.
Palladium (Pd)-catalyzed desulfitative cross-coupling reactions of sodium arylsulfinates with a w... more Palladium (Pd)-catalyzed desulfitative cross-coupling reactions of sodium arylsulfinates with a wide variety of arylboronic acids were achieved in good to excellent yields under simple aerobic conditions. These catalytic reactions could be accelerated by addition of a catalytic amount of Cu(II) salts as co-catalyst. Moreover, these reactions were tolerant to all of the tested functional groups, making them attractive alternatives to the traditional cross-coupling reactions.
An investigation into the physical and chemical characteristics of aluminum tris(8-hydroxyquinoli... more An investigation into the physical and chemical characteristics of aluminum tris(8-hydroxyquinoline) (Alq 3 ), a reliable electron-transporting and emitting material for low molecular weight based organic light-emitting diodes (OLEDs), was performed. In the ...
In mammals pyruvate kinase (PK) plays a key role in regulating the balance between glycolysis and... more In mammals pyruvate kinase (PK) plays a key role in regulating the balance between glycolysis and gluconeogenesis; however, in vivo regulation of PK flux by gluconeogenic hormones and substrates is poorly understood. To this end, we developed a novel nuclear magnetic resonance (NMR)-liquid chromatography/tandem-mass spectrometry (LC-MS/MS) method to directly assess pyruvate cycling relative to mitochondrial pyruvate metabolism (VPyr-Cyc/VMito) in vivo using [3-13C]lactate as a tracer. Using this approach VPyr-Cyc/VMito was only 6% in overnight fasted rats. In contrast, when propionate was infused simultaneously at doses previously used as a tracer, it increased VPyr-Cyc/VMito by 20-30 fold, increased hepatic TCA metabolite concentrations 2-3 fold and increased endogenous glucose production (EGP) rates by 20-100%. The physiologic stimuli, glucagon and epinephrine, both increased hepatic glucose production, but only glucagon suppressed VPyr-Cyc/VMito. These data highlight that under f...
A novel and efficient heterogeneous catalyst has been developed by immobilization of palladium on... more A novel and efficient heterogeneous catalyst has been developed by immobilization of palladium on the chlorinated polyvinylchloride nanofiber mats.
The relative ozonation rate constants for p-phenylenediamines have been estimated from the linear... more The relative ozonation rate constants for p-phenylenediamines have been estimated from the linear correlation of the ozonation rate constants with the ionization potentials (Figure 1). The efficient antiozonants were found to have relatively lower ionization potentials, but not too low to react with the atmospheric molecular oxygen. The bond dissociation enthalpies (BDEs) of the N—H bonds of p-aminodiphenylamine and related derivatives were found to be about 80 kcal/mol, suggesting that the p-aminodiphenylamines are not only efficient antiozonants, but are also efficient antioxidants. Efficient antiozonants should also be efficient antioxidants to quench the reactive radical intermediates formed during the degradation.
The equilibrium acidities (p K as) of six families of remotely substituted benzyl onium salts (ie... more The equilibrium acidities (p K as) of six families of remotely substituted benzyl onium salts (ie, 4-G-C6H4CH2-E+⊙ Br-, where E+= Ph3P+, Ph2PO, Et3N+, Me2S+, Me2Se+, and Bu2Te+ and G= H, Me, CF3, CO2Me, CN, and NO2), one family of α-E+ substituted ...
Supplemental material, EMS896708 Supplemental Material for Insight into nucleophilic fragmentatio... more Supplemental material, EMS896708 Supplemental Material for Insight into nucleophilic fragmentation mechanisms by glutamic acid side chain in singly protonated glutathione and related peptidyl ions by Liqun Fan, Jinhu Wang, Chunli Liu, Tiesheng Shi, Xian-Man Zhang, Yanqing Xia, Lina Fan and Yang Liu in European Journal of Mass Spectrometry
5) was also found to shift the proton resonances of the external homocarnosine from that of the i... more 5) was also found to shift the proton resonances of the external homocarnosine from that of the internal homocarnosine as shown in Figure 2. The chemical shift change caused by addition of TmDOTP 5was linearly correlated with the shift reagent concentration with a slope of 0.133 ppm/mM (R 2 =0.998), indicating that 0.3 mM of TmDOTP 5was sufficient to resolve the two resonances without significant line broadening. The encapsulation efficiencies determined directly from the separated internal and external proton resonance integrations are summarized in Table 1 for the DPPC liposomes prepared by extrusion through 50, 200 and 1000 nm polycarbonate membranes. Examination of Table 1 showed that the encapsulation efficiency increases as the liposome size increases, and the results from the two different experimental approaches were remarkably consistent with each other. Table 1. Encapsulation Efficiencies a a The total lipid concentration was 51 mg/ml. b The pore size of the polycarbonate ...
Caloric restriction without malnutrition (CR) is the most robust and reproducible way to extend l... more Caloric restriction without malnutrition (CR) is the most robust and reproducible way to extend lifespan and delay the onset of age-related diseases, such as hepatic steatosis, insulin resistance and type 2 diabetes (T2D). Unfortunately, the strict dietary regime necessary to achieve the beneficial effects of CR limits the use of this treatment to retard aging and disease in humans and new therapies are required. In this regard, our lab has recently developed a new class of therapeutic agents that are designed to safely promote liver-targeted mitochondrial uncoupling with a wide-therapeutic index. Our second-generation compound in this class is controlled-release mitochondrial protonophore (CRMP) that is functionally liver-targeted and promotes oxidation of hepatic triglycerides by promoting a subtle sustained increase in hepatic mitochondrial inefficiency. While we have previously demonstrated that this agent safely reverses hypertriglyceridemia, fatty liver, and hepatic inflammation/fibrosis in young-adult diet-induced rodent models of obesity, its effects on healthspan and lifespan remain to be determined. Here, we evaluated the impact of CRMP on hepatic steatosis and insulin action in aged 74-week-old male C57BL/6J mice fed a high-fat diet (HFD; 45% fat) for 12 weeks. Specifically, we demonstrate that CRMP treatment significantly reduced liver triglycerides, diacylglycerols, and transaminase levels independently of changes in body weight, whole-body energy expenditure or food intake. Additionally, long-term CRMP treatment reduced fasting plasma glucose concentrations (P Disclosure L. Goedeke: None. J. Camporez: None. A. Nasiri: None. Y. Wang: None. X. Zhang: None. G.I. Shulman: Advisory Panel; Self; AstraZeneca, Janssen Research & Development, Merck & Co., Inc., Novo Nordisk Inc.. Research Support; Self; Gilead Sciences, Inc..
Aluminum tris(8-hydroxyquinoline) (Alq3) is presently considered one of the most reliable electro... more Aluminum tris(8-hydroxyquinoline) (Alq3) is presently considered one of the most reliable electron transporting and emitting materials for molecular-based organic light emitting diodes (OLEDs). This paper discusses the effects of sample morphology on the hydrolysis and photoluminescence response of Alq3. The evolution of 8-hydroxyquinoline (8-Hq), a volatile byproduct of the hydrolysis of Alq3, was quantified using gas chromatography/mass spectroscopy (GC/MS) analysis on samples of different morphology. Annealed (more crystalline) samples exhibited greater chemical stability than freshly sublimed films, at the expense of photoluminescence efficiency. These phenomena are discussed with respect to possible failure mechanisms that Alq3-based OLEDs might undergo during prolonged operation.
Palladium (Pd)-catalyzed desulfitative cross-coupling reactions of sodium arylsulfinates with a w... more Palladium (Pd)-catalyzed desulfitative cross-coupling reactions of sodium arylsulfinates with a wide variety of arylboronic acids were achieved in good to excellent yields under simple aerobic conditions. These catalytic reactions could be accelerated by addition of a catalytic amount of Cu(II) salts as co-catalyst. Moreover, these reactions were tolerant to all of the tested functional groups, making them attractive alternatives to the traditional cross-coupling reactions.
An investigation into the physical and chemical characteristics of aluminum tris(8-hydroxyquinoli... more An investigation into the physical and chemical characteristics of aluminum tris(8-hydroxyquinoline) (Alq 3 ), a reliable electron-transporting and emitting material for low molecular weight based organic light-emitting diodes (OLEDs), was performed. In the ...
In mammals pyruvate kinase (PK) plays a key role in regulating the balance between glycolysis and... more In mammals pyruvate kinase (PK) plays a key role in regulating the balance between glycolysis and gluconeogenesis; however, in vivo regulation of PK flux by gluconeogenic hormones and substrates is poorly understood. To this end, we developed a novel nuclear magnetic resonance (NMR)-liquid chromatography/tandem-mass spectrometry (LC-MS/MS) method to directly assess pyruvate cycling relative to mitochondrial pyruvate metabolism (VPyr-Cyc/VMito) in vivo using [3-13C]lactate as a tracer. Using this approach VPyr-Cyc/VMito was only 6% in overnight fasted rats. In contrast, when propionate was infused simultaneously at doses previously used as a tracer, it increased VPyr-Cyc/VMito by 20-30 fold, increased hepatic TCA metabolite concentrations 2-3 fold and increased endogenous glucose production (EGP) rates by 20-100%. The physiologic stimuli, glucagon and epinephrine, both increased hepatic glucose production, but only glucagon suppressed VPyr-Cyc/VMito. These data highlight that under f...
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