A cationic gene delivery vector, guanidinylated disulfide-containing poly(amido amine)(CARCBA), was synthesized by Michael addition reaction between N,N′-cystaminebisacrylamide(CBA) and guanidine hydrochloride(CAR). ...A cationic gene delivery vector, guanidinylated disulfide-containing poly(amido amine)(CARCBA), was synthesized by Michael addition reaction between N,N′-cystaminebisacrylamide(CBA) and guanidine hydrochloride(CAR). Gel permeation chromatography(GPC) was used to evaluate the molecular weight of synthesized CAR-CBA. Polyethyleneimine(PEI) with molecular weight of 25 kDa was adopted as a reference, and polyethylene glycols(PEG) with different molecular weights were used to establish a standard curve for determining the molecular weight of CAR-CBA. The effects of two critical factors, namely columns and eluents,on the molecular weight measurement of CAR-CBA were investigated to optimize the GPC quantitative method. The results showed that Ultrahydrogel columns(120, 250) and HAc–NaAc(0.5 M, pH 4.5) buffer solution were the optimal column and GPC eluent, respectively.The molecular weight of the synthesized CAR-CBA was analyzed by the optimized GPC method and determined to be 24.66 kDa.展开更多
Polarity, partition coefficient (K), methanol carbon number of surfactant ((CMeOH)S), and methanol carbon number of surfactant head group ((CMeOH)HG) are measured on six alkanolamides and five polyoxyethylenated lon...Polarity, partition coefficient (K), methanol carbon number of surfactant ((CMeOH)S), and methanol carbon number of surfactant head group ((CMeOH)HG) are measured on six alkanolamides and five polyoxyethylenated long chain amines as stationary phases. From the measured methanol carbon numbers, polarity indices, (IP)S and (IP)HG, are calculated. The determined polarity terms are plotted against the head group weight fraction ( fHG ) of the investigated surfactants and several equations have been developed. The study reveals that the molecular structural gap between alkanolamides and polyoxyethylenated long chain amines diminished when HLB numbers of these surfactant classes are plotted against fHG values. Consequently, a general equation relating HLB and fHG is obtained.展开更多
AIM: To investigate the ocular biodistribution and clearance of topically administered 7-taurocholic acid conjugated low-molecular weight heparin(LHT7) in a neovascularized mouse cornea using an in vivo optical ima...AIM: To investigate the ocular biodistribution and clearance of topically administered 7-taurocholic acid conjugated low-molecular weight heparin(LHT7) in a neovascularized mouse cornea using an in vivo optical imaging system. METHODS: A total of 10 eyes of 6 to 8-week-old BALB/c mice were analyzed. Corneal neovascularization(CoNV) was induced in the inferior cornea(IC) of each animal by penetrating the stroma with two interrupted sutures. The development of CoNV was verified after one week and the area of each neovascularized region was measured. A near-infrared fluorescent probe of 20 μmol/L Cy5.5 labeled LHT7(LHT7-Cy5.5) in 0.02 mL solution was topically instilled onto the cornea in the experimental group(n=5). Free-Cy5.5 of 20 μmol/L in 0.02 mL was instilled in the control group(n=5). In vivo optical images were obtained before instillation and 5 min, 2, 4, and 6 h after instillation. The intensities were separately measured at the superior cornea(SC) and the IC. RESULTS: The mean CoNV areas were 1.97±0.17 mm^2 and 1.92±0.96 mm^2 in the experimental and control groups, respectively(P=0.832). The SC remained normal in all 10 subject animals. The IC intensity of the LHT7-Cy5.5 was greater than the SC intensity at 5 min(P=0.038), 2 h(P=0.041), and 4 h(P=0.041) after application. The IC intensity fell to less than half of its initial value(42.9%±8.6%) at 6 h in the experimental group. In the control mice, here were no significant differences in the free-Cy5.5 intensity between the IC and SC. CONCLUSION: Topically administered LHT7 shows a high biodistribution in CoNV areas for 4 h and should be reapplied accordingly to maintain its effects. In vivo optical imaging can be a useful tool for evaluating the ocular biodistribution of a drug in an animal model.展开更多
Pancreatic cancer(PC)is a devastating malignancy with fewer than 10%of patients being alive at 5 years after diagnosis.Venous thromboembolism(VTE)occurs in approximatively 20%of patients with PC,resulting in increased...Pancreatic cancer(PC)is a devastating malignancy with fewer than 10%of patients being alive at 5 years after diagnosis.Venous thromboembolism(VTE)occurs in approximatively 20%of patients with PC,resulting in increased morbidity,mortality and significant health care costs.The management of VTE is particularly challenging in these frail patients.Adequate selection of the most appropriate anticoagulant for each individual patient according to the current international guidelines is warranted for overcoming treatment challenges.The International Initiative on Thrombosis and Cancer multi-language web-based mobile application(downloadable for free at www.itaccme.com)has been developed to help clinicians in decision making in the most complex situations.In this narrative review,we will discuss the contemporary epidemiology and burden of VTE in PC patients,the performances and limitations of current risk assessment models to predict the risk of VTE,as well as evidence from recent clinical trials for the primary prophylaxis and treatment of cancer-associated VTE that support updated clinical practice guidelines.展开更多
基金the National Natural Science Foundation of China for financial support(No.81373335)
文摘A cationic gene delivery vector, guanidinylated disulfide-containing poly(amido amine)(CARCBA), was synthesized by Michael addition reaction between N,N′-cystaminebisacrylamide(CBA) and guanidine hydrochloride(CAR). Gel permeation chromatography(GPC) was used to evaluate the molecular weight of synthesized CAR-CBA. Polyethyleneimine(PEI) with molecular weight of 25 kDa was adopted as a reference, and polyethylene glycols(PEG) with different molecular weights were used to establish a standard curve for determining the molecular weight of CAR-CBA. The effects of two critical factors, namely columns and eluents,on the molecular weight measurement of CAR-CBA were investigated to optimize the GPC quantitative method. The results showed that Ultrahydrogel columns(120, 250) and HAc–NaAc(0.5 M, pH 4.5) buffer solution were the optimal column and GPC eluent, respectively.The molecular weight of the synthesized CAR-CBA was analyzed by the optimized GPC method and determined to be 24.66 kDa.
文摘Polarity, partition coefficient (K), methanol carbon number of surfactant ((CMeOH)S), and methanol carbon number of surfactant head group ((CMeOH)HG) are measured on six alkanolamides and five polyoxyethylenated long chain amines as stationary phases. From the measured methanol carbon numbers, polarity indices, (IP)S and (IP)HG, are calculated. The determined polarity terms are plotted against the head group weight fraction ( fHG ) of the investigated surfactants and several equations have been developed. The study reveals that the molecular structural gap between alkanolamides and polyoxyethylenated long chain amines diminished when HLB numbers of these surfactant classes are plotted against fHG values. Consequently, a general equation relating HLB and fHG is obtained.
基金Supported by a grant(No.2016-7026)from the Asan Institute for Life Science,Seoul,Republic of Korea
文摘AIM: To investigate the ocular biodistribution and clearance of topically administered 7-taurocholic acid conjugated low-molecular weight heparin(LHT7) in a neovascularized mouse cornea using an in vivo optical imaging system. METHODS: A total of 10 eyes of 6 to 8-week-old BALB/c mice were analyzed. Corneal neovascularization(CoNV) was induced in the inferior cornea(IC) of each animal by penetrating the stroma with two interrupted sutures. The development of CoNV was verified after one week and the area of each neovascularized region was measured. A near-infrared fluorescent probe of 20 μmol/L Cy5.5 labeled LHT7(LHT7-Cy5.5) in 0.02 mL solution was topically instilled onto the cornea in the experimental group(n=5). Free-Cy5.5 of 20 μmol/L in 0.02 mL was instilled in the control group(n=5). In vivo optical images were obtained before instillation and 5 min, 2, 4, and 6 h after instillation. The intensities were separately measured at the superior cornea(SC) and the IC. RESULTS: The mean CoNV areas were 1.97±0.17 mm^2 and 1.92±0.96 mm^2 in the experimental and control groups, respectively(P=0.832). The SC remained normal in all 10 subject animals. The IC intensity of the LHT7-Cy5.5 was greater than the SC intensity at 5 min(P=0.038), 2 h(P=0.041), and 4 h(P=0.041) after application. The IC intensity fell to less than half of its initial value(42.9%±8.6%) at 6 h in the experimental group. In the control mice, here were no significant differences in the free-Cy5.5 intensity between the IC and SC. CONCLUSION: Topically administered LHT7 shows a high biodistribution in CoNV areas for 4 h and should be reapplied accordingly to maintain its effects. In vivo optical imaging can be a useful tool for evaluating the ocular biodistribution of a drug in an animal model.
文摘Pancreatic cancer(PC)is a devastating malignancy with fewer than 10%of patients being alive at 5 years after diagnosis.Venous thromboembolism(VTE)occurs in approximatively 20%of patients with PC,resulting in increased morbidity,mortality and significant health care costs.The management of VTE is particularly challenging in these frail patients.Adequate selection of the most appropriate anticoagulant for each individual patient according to the current international guidelines is warranted for overcoming treatment challenges.The International Initiative on Thrombosis and Cancer multi-language web-based mobile application(downloadable for free at www.itaccme.com)has been developed to help clinicians in decision making in the most complex situations.In this narrative review,we will discuss the contemporary epidemiology and burden of VTE in PC patients,the performances and limitations of current risk assessment models to predict the risk of VTE,as well as evidence from recent clinical trials for the primary prophylaxis and treatment of cancer-associated VTE that support updated clinical practice guidelines.