Biomedical subjects
Publications and source records attributed to A Matsuda.
An efficient synthesis of cyclic ADP-carbocyclic-ribose (2), as a stable mimic for cyclic ADP-ribose, was achieved. Treatment of N1-carbocyclic-ribosyladenosine bisphosphate derivative 10 with AgNO3 in the presence of molecular sieves 3A in pyridine gave the desired cyclic product in 93% yield, which was deprotected to give the target cyclic ADP-carbocyclic-ribose (2).
PURPOSE: To investigate the correlation between monocyte chemotactic protein-1 (MCP-1) levels in the vitreous and clinical findings in eyes with proliferative diabetic retinopathy (PDR). METHODS: We assayed MCP-1 levels by ELISA in vitreous samples of 88 consecutive patients with PDR (52 eyes) and macular holes or idiopathic epimacular membrane (controls, 36 eyes). RESULTS: The level of MCP-1 in the vitreous was 2,097.5 +/- 1,099.4 pg/ml (mean +/- SD) in PDR, and 504.3 +/- 405.6 pg/ml in the controls. In PDR eyes, multivariate regression analysis revealed a significant association between MCP-1 levels in the vitreous and the degree of proliferative membrane, and a significant negative association between MCP-1 levels and the extent of preoperative retinal photocoagulation. CONCLUSION: The results suggest that MCP-1 may play a role in the development of the proliferative phase of PDR.
C-peptide immunoreactivity (CPR) in 24-h urine was assayed in 13 diabetic patients during and after recovery from ketoacidosis. In 10 patients who remained insulin-dependent on discharge and in the subsequent follow-up period, urine CPR was low (18 micrograms/day or less), while in three patients who were ultimately controlled by diet or sulfonylureas, urine CPR was normal (59-92 micrograms/day, normal value 74 +/- 26 micrograms/day). In the latter group, urine CPR in one patient assayed during ketoacidosis was 6 micrograms/day and, in another patient, it was 22 micrograms/day on the 3rd day of the admission. This may imply that in the latter group, B-cell function was decompensated in ketoacidosis, but was restored after recovery. Clinical courses suggested that these patients were not in the remission phase of IDDM, but belonged to NIDDM. Among other groups of diabetic patients, urine CPR in those treated with diet or sulfonylureas was 72 +/- 30 micrograms/day and always higher than 20 micrograms/day. The prevalence of urine CPR less than 20 micrograms/day was more frequent in those with younger onset of diabetes, higher insulin dosage, unstable diabetes, or previous history of ketoacidosis among insulin-treated patients. We suggest that urine CPR less than 20 micrograms/day is an index of insulin dependency, although in a state of extreme decompensation of B-cells such as in ketoacidosis, urine CPR can be decreased low even in NIDDM.
The pharmacokinetics and pharmacologic effects of human insulin (Novo) derived from porcine insulin were studied by a double-blind crossover comparison with porcine monocomponent insulin in healthy volunteers. Both insulins were given by subcutaneous (s.c.) and intravenous (i.v.) injection to healthy male volunteers. The doses of injected insulin were 0.05 U/kg and 0.1 U/kg for the s.c. study, and 0.025 U/kg and 0.05 U/kg for the i.v. study. The plasma immunoreactive insulin (IRI) increased rapidly, plasma C-peptide and glucose decreased gradually, and plasma glucagon increased transiently after injection of the insulins. The pharmacokinetics and pharmacologic actions of human insulin were essentially similar to those of porcine insulin. The area under the time-concentration curve (AUC) of IRI was slightly greater after s.c. injection of human insulin than after that of porcine insulin at the 0.05-U/kg dose level. Because no significant difference was observed in the plasma C-peptide level and no such difference was noticed in the AUC of IRI between the two insulins after i.v. injection, the bioavailability of human insulin seemed to be greater than that of porcine insulin after s.c. injection. The plasma glucose-reducing effect was slightly greater after s.c. injection of 0.05 U/kg of human insulin than after s.c. injection of the same dose of porcine insulin. Apart from symptoms of hypoglycemia (sweating, palpitations, and hot flushes), no other unwanted reactions were observed after administration of either insulin. These results suggest that human insulin has a usefulness similar to that of porcine insulin in clinical practice. The clinical relevance of the slight difference in bioavailability observed in the s.c. study remains to be investigated.