Chronic pancreatitis (CP) is a progressive inflammatory disorder of the pancreas. It is predominantly idiopathic (with an unknown cause) in India and mostly due to alcohol in the West. Diabetes that occur secondary to...Chronic pancreatitis (CP) is a progressive inflammatory disorder of the pancreas. It is predominantly idiopathic (with an unknown cause) in India and mostly due to alcohol in the West. Diabetes that occur secondary to chronic pancreatitis (T3c Diabetes) is often brittle, and is difficult to attain normoglycemia with conventional treatment requiring multiple doses of insulin. Mild and severe model of CP was induced in mice by repeated intraperitoneal injections of cerulein and L-arginine respectively with an intent to study islet dysfunction and develop therapeutic strategy in animal models of CP. Dietary intervention of epigallocatechin-3-gallate (EGCG) was tested in both the models of CP for its beneficial effects on insulin secretory functions. Pancreata collected upon euthanasia were used to study alterations in the morphology of pancreatic parenchyma and inflammation by staining with H&E and fibrotic changes by Masson’s trichrome and picrosirius staining. Insulin secretory functions of islets were evaluated to test the efficacy of the dietary intervention on β-cell functions. Intraperitoneal glucose tolerance test was performed to monitor the glucose homeostasis before and after the dietary intervention. Both the models resulted in CP with dispersed acini, inflammation and fibrosis. The loss of acini and extent of fibrosis was more in L-arginine model. 2-fold improvement in glucose-stimulated insulin secretory functions of islets was observed with 0.5% EGCG dietary intervention in cerulein model of CP and 1.6-fold in L-arginine model of CP. A further improvement in insulin secretion by 3.2-fold was observed with additional dietary supplements like N-acetyl cysteine, curcumin in combination with EGCG. Our results thus demonstrate and highlight the therapeutic potential of dietary green tea (EGCG) supplementation in reversing islet dysfunction and improving glucose homeostasis in experimental chronic pancreatitis in mice.展开更多
AIM: To investigate the potential role of oxidative stress and the possible therapeutic effects of N-acetyl cysteine (NAC), amifostine (AMF) and ascorbic acid (ASC) in methotrexate (MTX)-induced hepatotoxicity.
The triphenyltin complex with salicylidene-2-aminophenol （C31H24NO2Sn, 1） has been synthesized and characterized by elemental analysis, IR spectroscopy, thermogravimetric analysis, and X-ray single-crystal diffracti...The triphenyltin complex with salicylidene-2-aminophenol （C31H24NO2Sn, 1） has been synthesized and characterized by elemental analysis, IR spectroscopy, thermogravimetric analysis, and X-ray single-crystal diffraction. The complex crystallizes in monoclinic system, P21/c space group with a = 1.09515（8）, b = 1.17739（8）, c = 2.29075（14） nm, β = 117.070（4）°, V = 2.6302（3） nm3, Z = 4, Dc = 1.417 g/cm3, ？ = 0.999 mm–1, F（000） = 1123, R = 0.0472 and wR = 0.1169. X-ray single-crystal diffraction showed that 1 demonstrates a one-dimensional chain structure. The quantum chemical calculation of 1 has been investigated. Complex 1 emits fluo- rescence at 558 nm and exhibits certain inhibitory activity against NCI-H460, A549 and MCF-7.展开更多
The exploration of C2-symmetric chiral aminophenols and aminonaphthols is described. Seven new ligands have been successfully synthesized using Mannich reaction as a key step. Four of them have C2-symmetry and their s...The exploration of C2-symmetric chiral aminophenols and aminonaphthols is described. Seven new ligands have been successfully synthesized using Mannich reaction as a key step. Four of them have C2-symmetry and their structure has been fully characterized by means of NMR and X-ray crystallography.展开更多
The oxidative polycondensation reaction conditions of 2-[(2-hydroxyphenyliminomethylbenzylidene)amino- phenol](2-HPIMBAP)has been accomplished by using air O_2 and NaOCl oxidants in an aqueous alkaline medium between ...The oxidative polycondensation reaction conditions of 2-[(2-hydroxyphenyliminomethylbenzylidene)amino- phenol](2-HPIMBAP)has been accomplished by using air O_2 and NaOCl oxidants in an aqueous alkaline medium between 50-90℃.The optimum reaction conditions of the oxidative polycondensation and the main parameters of the process were established.At the optimum reaction conditions,yield of the products were found to be 67.72% and 61.49% for air O_2 and NaOCl oxidants respectively.The structures of the monomer ...展开更多
The optimum reaction conditions of the oxidative polycondensation of 2-(thien-2-yl-methylene)aminophenol (2-TMAP) has been accomplished by using air O_2,H_2O_2 and NaOCl oxidants in an aqueous alkaline medium between...The optimum reaction conditions of the oxidative polycondensation of 2-(thien-2-yl-methylene)aminophenol (2-TMAP) has been accomplished by using air O_2,H_2O_2 and NaOCl oxidants in an aqueous alkaline medium between 20℃and 90℃.The structures of the monomer and oligomer were confirmed by FT-IR,UV-Vis,~1H-NMR and ^(13)C-NMR and elemental analysis.TGA-DTA,size exclusion chromatography(SEC) techniques and solubility tests were applied for characterization.The ~1H-NMR and ^(13)C-NMR data show that the polymeriz...展开更多
The syntheses of a library of new chiral aminophenolate bidentate O,N-type ligands HOC<sub>6</sub>H<sub>4</sub>(2-R- 4-R′)CH<sub>2</sub>N(Me)CH(Me)C<sub>6</sub>H<sub...The syntheses of a library of new chiral aminophenolate bidentate O,N-type ligands HOC<sub>6</sub>H<sub>4</sub>(2-R- 4-R′)CH<sub>2</sub>N(Me)CH(Me)C<sub>6</sub>H<sub>5</sub> [R = R′ = Bu<sup>t</sup>, 1;R = R′ = Pent, 2;R = Bu<sup>t</sup>, R′ = Me, 3;R = Me, R′ = Bu<sup>t</sup>, 4;R = R′ = Me, 5] and tridentate O,N,O-type ligands HOC<sub>6</sub>H<sub>4</sub>(2,4-Bu<sup>t</sup>)CH = NCH(R′′)C<sub>6</sub>H<sub>5</sub> [R′′ = Me, 6;R′′ = CH<sub>2</sub>OMe, 7] are reported. These ligands were characterized by elemental analysis, nuclear magnetic resonance spectroscopy (<sup>1</sup>H &<sup> 13</sup>C), and single crystal X-ray diffraction. These ligands serve as chiral auxiliaries for inorganic chemists to design chiral metal-based complexes for asymmetric catalysis and stereoselective polymerization reactions. Three new heteroleptic zinc complexes based on these ligands have been synthesized in moderate yields via a ligand-exchange transamination reaction between homoleptic [Zn(N(SiMe<sub>3</sub>)<sub>2</sub>)<sub>2</sub>] and one equivalent of corresponding ligands to afford [L<sup>3</sup>ZnN- (SiMe<sub>3</sub>)<sub>2</sub>] (3a), [L<sup>4</sup>ZnN(SiMe<sub>3</sub>)<sub>2</sub>] (4a), and [L<sup>7</sup>ZnN(SiMe<sub>3</sub>)<sub>2</sub>] (7a). Solvent-free polymerization of raclactide at 130°C using these zinc compounds yielded atactic polylactides with Mw 10,000 g/mol and narrow polydispersity of 1.3.展开更多
Specific, precise and sensitive TLC-Densitometric method was developed and validated for the simultaneous estimation of N-Acetyl cysteine and Taurine in active pharmaceutical ingredient and pharmaceutical dosage form....Specific, precise and sensitive TLC-Densitometric method was developed and validated for the simultaneous estimation of N-Acetyl cysteine and Taurine in active pharmaceutical ingredient and pharmaceutical dosage form. An effective separation was achieved on pre-coated silica gel HPTLC plates by using n-butanol:acetic acid:water (8:0.5:1.5 v/v/v). The spots were scanned densitometrically at 295 nm. The RF values of N-Acetyl cysteine and Taurine were found to be 0.29 and 0.52, respectively. Calibration curves were linear in the range of 30 - 180 and 100 - 600 ng/band for N-Acetyl cysteine and Taurine, correspondingly with correlation coefficients of 0.999. The developed method was validated as per ICH guidelines. The limits of detection were 11.24 and 63.40 ng/spot for NAC and TAU respectively. The method developed was found to be precise and specific for the simultaneous analysis of N-Acetyl cysteine and Taurine in pure and tablet dosage form.展开更多
Background: M. oleifera is a highly valued medicinal plant used widely from time immemorial to treat various ailments. However, with continued un-standardized use of the plant leaves, studies have reported organ toxic...Background: M. oleifera is a highly valued medicinal plant used widely from time immemorial to treat various ailments. However, with continued un-standardized use of the plant leaves, studies have reported organ toxicity to the liver, kidney and the heart. As communities continue to use M. oleifera leaves for its medicinal and nutritional values, there is need to find an antidote for its hepatotoxicity. Aim: The study established the reversal effect of N-Acetyl Cysteine (NAC) on M. oleifera aqueous leaf extract-induced hepatotoxicity in Wistar albino rats. Methods: Twenty-four (24) rats received a toxic dose (8.05 g/kg bwt) of M. oleifera leaf extract for 28 days to cause sub-acute hepatotoxicity. They were divided into 4 groups of 6 rats each. Group I received 1 ml normal (control group), Group II received 1000 ng/kg NAC, Group III received 1200 mg/kg NAC and Group IV received 1500 mg/kg NAC. Another group of 6 rats (Group V) received 0.75 mg/kg Paracetamol to cause hepatotoxicity. Group V (a positive control) received the prescribed clinical dose of 1200 mg/kg NAC which reverses the hepatotoxicity. All the NAC doses were given once a day intragastric for 7 days. On days: 1, 3 and 7 of receiving NAC, liver serum enzymes and bilirubin were measured. On day 7 the animals were sacrificed and liver tissue harvested for histopathology analysis. Results: A dose of 8.05 g/kg of M. oleifera leaf extract and 0.75 mg/kg Paracetamol were able to induce hepatotoxicity in Wister albino rats in 28 days. The M. oleifera extract induced hepatotoxic rats treated with NAC at doses of 1000 mg/kg, 1200 mg/kg and 1500 mg/kg, had a reduction in mean serum liver enzymes, plus reduced mean serum bilirubin levels. The liver histopathological analysis showed reduced inflammation after treatment with NAC for 3 and 7 days in the M. oleifera and paracetamol induced hepatotoxic rats. Conclusion: NAC can reverse M. oleifera leaf aqueous extract-induced sub-acute hepatotoxicity in Wistar Albino rats.展开更多
The gold electrodes coated by n-alkanethiol with various chain lengths were used to study the permeability of uric acid,ascorbic acid,4-aminophenol,paracetanol and phenacetin by means of linear sweep voltammetry.The r...The gold electrodes coated by n-alkanethiol with various chain lengths were used to study the permeability of uric acid,ascorbic acid,4-aminophenol,paracetanol and phenacetin by means of linear sweep voltammetry.The results show that the optimum chain length is n=10.The improvements in the selectivity and the stability of the amperometric detection of these compounds in a flow stream were obtained by n-alkanethiol self assembled monolayers modified electrodes based on their differences in the hydrophobicity and the permeability.展开更多
N-acetyl cysteine(NAC)is a promising drug for prophylaxis and treatment of coronavirus disease 2019(COVID-19)based on antioxidant and anti-inflammatory mechanisms.Further studies with cautious approach are needed to e...N-acetyl cysteine(NAC)is a promising drug for prophylaxis and treatment of coronavirus disease 2019(COVID-19)based on antioxidant and anti-inflammatory mechanisms.Further studies with cautious approach are needed to establish the benefits and risks before considering NAC as an adjuvant treatment for COVID-19.展开更多
Although several considerations have been raised suggesting a beneficial effect of N-acetyl cysteine(NAC)for the treatment of severe acute respiratory syndrome coronavirus 2 infection,there is currently no clinical ev...Although several considerations have been raised suggesting a beneficial effect of N-acetyl cysteine(NAC)for the treatment of severe acute respiratory syndrome coronavirus 2 infection,there is currently no clinical evidence that NAC truly prevents coronavirus disease 2019(COVID-19),reduces the severity of the disease,or improves the outcome.Appropriately designed clinical trials are warranted to prove or disprove a therapeutic effect of NAC for COVID-19 patients.展开更多
文摘Chronic pancreatitis (CP) is a progressive inflammatory disorder of the pancreas. It is predominantly idiopathic (with an unknown cause) in India and mostly due to alcohol in the West. Diabetes that occur secondary to chronic pancreatitis (T3c Diabetes) is often brittle, and is difficult to attain normoglycemia with conventional treatment requiring multiple doses of insulin. Mild and severe model of CP was induced in mice by repeated intraperitoneal injections of cerulein and L-arginine respectively with an intent to study islet dysfunction and develop therapeutic strategy in animal models of CP. Dietary intervention of epigallocatechin-3-gallate (EGCG) was tested in both the models of CP for its beneficial effects on insulin secretory functions. Pancreata collected upon euthanasia were used to study alterations in the morphology of pancreatic parenchyma and inflammation by staining with H&E and fibrotic changes by Masson’s trichrome and picrosirius staining. Insulin secretory functions of islets were evaluated to test the efficacy of the dietary intervention on β-cell functions. Intraperitoneal glucose tolerance test was performed to monitor the glucose homeostasis before and after the dietary intervention. Both the models resulted in CP with dispersed acini, inflammation and fibrosis. The loss of acini and extent of fibrosis was more in L-arginine model. 2-fold improvement in glucose-stimulated insulin secretory functions of islets was observed with 0.5% EGCG dietary intervention in cerulein model of CP and 1.6-fold in L-arginine model of CP. A further improvement in insulin secretion by 3.2-fold was observed with additional dietary supplements like N-acetyl cysteine, curcumin in combination with EGCG. Our results thus demonstrate and highlight the therapeutic potential of dietary green tea (EGCG) supplementation in reversing islet dysfunction and improving glucose homeostasis in experimental chronic pancreatitis in mice.
文摘AIM: To investigate the potential role of oxidative stress and the possible therapeutic effects of N-acetyl cysteine (NAC), amifostine (AMF) and ascorbic acid (ASC) in methotrexate (MTX)-induced hepatotoxicity.
基金Supported by the Open Fund Project of Key Laboratory of Functional Organometallic Materials of Hengyang Normal University(15K017,14K014,13K105)Natural Science Foundation of Hunan Province(No.13JJ3112)+3 种基金Scientific&Technological Projects of Hunan Province(No.2014NK3086)Aid programs for Science and Technology Innovative Research Team in Higher Educational Institutions of Hunan Provincethe Key Discipline of Hunan ProvinceProject funding for research and innovation experiment of university students in Hunan Province
文摘The triphenyltin complex with salicylidene-2-aminophenol （C31H24NO2Sn, 1） has been synthesized and characterized by elemental analysis, IR spectroscopy, thermogravimetric analysis, and X-ray single-crystal diffraction. The complex crystallizes in monoclinic system, P21/c space group with a = 1.09515（8）, b = 1.17739（8）, c = 2.29075（14） nm, β = 117.070（4）°, V = 2.6302（3） nm3, Z = 4, Dc = 1.417 g/cm3, ？ = 0.999 mm–1, F（000） = 1123, R = 0.0472 and wR = 0.1169. X-ray single-crystal diffraction showed that 1 demonstrates a one-dimensional chain structure. The quantum chemical calculation of 1 has been investigated. Complex 1 emits fluo- rescence at 558 nm and exhibits certain inhibitory activity against NCI-H460, A549 and MCF-7.
基金This work was financially supported by the National Natural Science Foundation of China(Grant No.20172008),which is greatly appreciated.
文摘The exploration of C2-symmetric chiral aminophenols and aminonaphthols is described. Seven new ligands have been successfully synthesized using Mannich reaction as a key step. Four of them have C2-symmetry and their structure has been fully characterized by means of NMR and X-ray crystallography.
基金This work was supported by the Canakkale Onsekiz Mart University Scientific Research Projects Commission for financial support(No.2007/20).
文摘The oxidative polycondensation reaction conditions of 2-[(2-hydroxyphenyliminomethylbenzylidene)amino- phenol](2-HPIMBAP)has been accomplished by using air O_2 and NaOCl oxidants in an aqueous alkaline medium between 50-90℃.The optimum reaction conditions of the oxidative polycondensation and the main parameters of the process were established.At the optimum reaction conditions,yield of the products were found to be 67.72% and 61.49% for air O_2 and NaOCl oxidants respectively.The structures of the monomer ...
基金supported by the Government Planning Organization(GPO2002K120170-7)TUBITAK GrantsCommission for a research grant(No.TBAG-105T428).
文摘The optimum reaction conditions of the oxidative polycondensation of 2-(thien-2-yl-methylene)aminophenol (2-TMAP) has been accomplished by using air O_2,H_2O_2 and NaOCl oxidants in an aqueous alkaline medium between 20℃and 90℃.The structures of the monomer and oligomer were confirmed by FT-IR,UV-Vis,~1H-NMR and ^(13)C-NMR and elemental analysis.TGA-DTA,size exclusion chromatography(SEC) techniques and solubility tests were applied for characterization.The ~1H-NMR and ^(13)C-NMR data show that the polymeriz...
文摘The syntheses of a library of new chiral aminophenolate bidentate O,N-type ligands HOC<sub>6</sub>H<sub>4</sub>(2-R- 4-R′)CH<sub>2</sub>N(Me)CH(Me)C<sub>6</sub>H<sub>5</sub> [R = R′ = Bu<sup>t</sup>, 1;R = R′ = Pent, 2;R = Bu<sup>t</sup>, R′ = Me, 3;R = Me, R′ = Bu<sup>t</sup>, 4;R = R′ = Me, 5] and tridentate O,N,O-type ligands HOC<sub>6</sub>H<sub>4</sub>(2,4-Bu<sup>t</sup>)CH = NCH(R′′)C<sub>6</sub>H<sub>5</sub> [R′′ = Me, 6;R′′ = CH<sub>2</sub>OMe, 7] are reported. These ligands were characterized by elemental analysis, nuclear magnetic resonance spectroscopy (<sup>1</sup>H &<sup> 13</sup>C), and single crystal X-ray diffraction. These ligands serve as chiral auxiliaries for inorganic chemists to design chiral metal-based complexes for asymmetric catalysis and stereoselective polymerization reactions. Three new heteroleptic zinc complexes based on these ligands have been synthesized in moderate yields via a ligand-exchange transamination reaction between homoleptic [Zn(N(SiMe<sub>3</sub>)<sub>2</sub>)<sub>2</sub>] and one equivalent of corresponding ligands to afford [L<sup>3</sup>ZnN- (SiMe<sub>3</sub>)<sub>2</sub>] (3a), [L<sup>4</sup>ZnN(SiMe<sub>3</sub>)<sub>2</sub>] (4a), and [L<sup>7</sup>ZnN(SiMe<sub>3</sub>)<sub>2</sub>] (7a). Solvent-free polymerization of raclactide at 130°C using these zinc compounds yielded atactic polylactides with Mw 10,000 g/mol and narrow polydispersity of 1.3.
文摘Specific, precise and sensitive TLC-Densitometric method was developed and validated for the simultaneous estimation of N-Acetyl cysteine and Taurine in active pharmaceutical ingredient and pharmaceutical dosage form. An effective separation was achieved on pre-coated silica gel HPTLC plates by using n-butanol:acetic acid:water (8:0.5:1.5 v/v/v). The spots were scanned densitometrically at 295 nm. The RF values of N-Acetyl cysteine and Taurine were found to be 0.29 and 0.52, respectively. Calibration curves were linear in the range of 30 - 180 and 100 - 600 ng/band for N-Acetyl cysteine and Taurine, correspondingly with correlation coefficients of 0.999. The developed method was validated as per ICH guidelines. The limits of detection were 11.24 and 63.40 ng/spot for NAC and TAU respectively. The method developed was found to be precise and specific for the simultaneous analysis of N-Acetyl cysteine and Taurine in pure and tablet dosage form.
文摘Background: M. oleifera is a highly valued medicinal plant used widely from time immemorial to treat various ailments. However, with continued un-standardized use of the plant leaves, studies have reported organ toxicity to the liver, kidney and the heart. As communities continue to use M. oleifera leaves for its medicinal and nutritional values, there is need to find an antidote for its hepatotoxicity. Aim: The study established the reversal effect of N-Acetyl Cysteine (NAC) on M. oleifera aqueous leaf extract-induced hepatotoxicity in Wistar albino rats. Methods: Twenty-four (24) rats received a toxic dose (8.05 g/kg bwt) of M. oleifera leaf extract for 28 days to cause sub-acute hepatotoxicity. They were divided into 4 groups of 6 rats each. Group I received 1 ml normal (control group), Group II received 1000 ng/kg NAC, Group III received 1200 mg/kg NAC and Group IV received 1500 mg/kg NAC. Another group of 6 rats (Group V) received 0.75 mg/kg Paracetamol to cause hepatotoxicity. Group V (a positive control) received the prescribed clinical dose of 1200 mg/kg NAC which reverses the hepatotoxicity. All the NAC doses were given once a day intragastric for 7 days. On days: 1, 3 and 7 of receiving NAC, liver serum enzymes and bilirubin were measured. On day 7 the animals were sacrificed and liver tissue harvested for histopathology analysis. Results: A dose of 8.05 g/kg of M. oleifera leaf extract and 0.75 mg/kg Paracetamol were able to induce hepatotoxicity in Wister albino rats in 28 days. The M. oleifera extract induced hepatotoxic rats treated with NAC at doses of 1000 mg/kg, 1200 mg/kg and 1500 mg/kg, had a reduction in mean serum liver enzymes, plus reduced mean serum bilirubin levels. The liver histopathological analysis showed reduced inflammation after treatment with NAC for 3 and 7 days in the M. oleifera and paracetamol induced hepatotoxic rats. Conclusion: NAC can reverse M. oleifera leaf aqueous extract-induced sub-acute hepatotoxicity in Wistar Albino rats.
文摘The gold electrodes coated by n-alkanethiol with various chain lengths were used to study the permeability of uric acid,ascorbic acid,4-aminophenol,paracetanol and phenacetin by means of linear sweep voltammetry.The results show that the optimum chain length is n=10.The improvements in the selectivity and the stability of the amperometric detection of these compounds in a flow stream were obtained by n-alkanethiol self assembled monolayers modified electrodes based on their differences in the hydrophobicity and the permeability.
文摘N-acetyl cysteine(NAC)is a promising drug for prophylaxis and treatment of coronavirus disease 2019(COVID-19)based on antioxidant and anti-inflammatory mechanisms.Further studies with cautious approach are needed to establish the benefits and risks before considering NAC as an adjuvant treatment for COVID-19.
文摘Although several considerations have been raised suggesting a beneficial effect of N-acetyl cysteine(NAC)for the treatment of severe acute respiratory syndrome coronavirus 2 infection,there is currently no clinical evidence that NAC truly prevents coronavirus disease 2019(COVID-19),reduces the severity of the disease,or improves the outcome.Appropriately designed clinical trials are warranted to prove or disprove a therapeutic effect of NAC for COVID-19 patients.
