Amount and distribution of dietary protein affects clinical response to levodopa in Parkinson's disease

Reducing dietary protein improves the effectiveness of levodopa (LD) but the most effective distribution of a low-protein diet (0.8 g/kg) is unclear. We compared a 1.6 g/kg protein diet, a 0.8 g/kg diet with protein evenly distributed between meals, and a 0.8 g/kg diet with protein restricted to the evening meal in 5 parkinsonian patients with motor fluctuations. We monitored clinical response, plasma LD, and plasma large amino acids (LNAAs) hourly throughout the day. Mean "on" times were 51% (1.6 g/kg diet), 67% (0.8 g/kg evenly distributed), and 77% (0.8 g/kg restricted). Hourly averages of plasma LD did not differ between the diets. The mean plasma LNAAs were 732 nmol/ml (1.6 g/kg diet), 640 (0.8 g/kg distributed), and 542 (0.8 g/kg restricted), and the diurnal pattern reflected the distribution of protein intake. In conclusion, the amount and distribution of dietary protein affect clinical response to LD. These effects are not related to LD absorption but are explained by the variation in plasma LNAAs.     

Pigment vs cholesterol cholelithiasis: Comparison of stone and bile composition

This report presents a comparative study of gallstone and gallbladder bile composition from 100 unselected American patients, 23 with pigment and 77 with cholesterol cholelithiasis. Cholesterol stones were predominantly composed of cholesterol, whereas pigment stones were mainly composed of an unidentified residue, bilirubin, and bile salts. The residue in pigment stones was not calcium bilirubinate, which sharply contrasts with the composition of bile pigment calcium stones found in Japanese subjects. Bile composition of the two groups differed in that the cholesterol content of biles surrounding pigment stones was significantly less than that of biles surrounding cholesterol stones. Bilirubin in biles was conjugated, but the pigment extracted from stones was unconjugated bilirubin. This study indicates that (1) pigment stones account for an appreciable percentage of gallstone specimens found at cholecystectomy, and (2) pigment stone formation involves the precipitation of bilirubin, bile salts, and unidentified material which is not calcium bilirubinate.Presented at the meetings of the American Federation of Clinical Research, April 29, 1973, Atlantic City, New Jersey. Supported in part by NIH grant AM 14543. Dr. Trotman is a former NIH trainee under NIH grant AM 05462 and currently a recipient of a Macy Foundation Faculty Fellowship.     

Marked alkaline phosphatase elevation with partial common bile duct obstruction due to calcific pancreatitis.

This study characterizes a syndrome of partial common bile duct obstruction and marked elevation in serum alkaline phosphatase in 6 male alcoholic patients with calcific pancreatitis. In each patient, a marked elevation in serum alkaline phosphatase was associated with minimal, if any, elevation in serum bilirubin. In all cases, the alkaline phosphatase was hepatic in origin, and intravenous or operative cholangiography showed a dilated common bile duct. Liver biopsy showed canalicular bile stasis in 4 patients and bile duct proliferation in 2 patients. This study demonstrates that calcific pancreatitis may cause partial bile duct obstruction which differentially increases serum alkaline phosphatase without altering bilirubin or bromsulphthalein excretion.     

Comparison of twice-daily ranitidine with standard cimetidine treatment of duodenal ulcer.

One hundred and three outpatients with endoscopically diagnosed duodenal ulcer were randomly allocated to treatment with either cimetidine 200 mg tds and 400 mg nocte, or ranitidine 150 mg bd for four weeks. The endoscopists were not aware of the treatment and took no part in the clinical management. On completion of treatment ulcers had healed in 43 of 51 (84%) patients given cimetidine and in 40 of 52 (77%) patients given ranitidine. There were no serious unwanted effects in either treatment group. The results show no significant difference between healing rates after four weeks of standard cimetidine therapy or ranitidine 150 mg bd.     

Predictors of survival in very low birth weight infants at the University Hospital of the West Indies, Jamaica

The use of prenatal steroids is an effective, simple clinical intervention that can be implemented in developing countries to help decrease mortality in very low birth weight infants.     

Human umbilical cord stem cell encapsulation in novel macroporous and injectable fibrin for muscle tissue engineering

There has been little research on the seeding of human umbilical cord mesenchymal stem cells (hUCMSCs) in three-dimensional scaffolds for muscle tissue engineering. The objectives of this study were: (i) to seed hUCMSCs in a fibrin hydrogel containing fast-degradable microbeads (dMBs) to create macropores to enhance cell viability; and (ii) to investigate the encapsulated cell proliferation and myogenic differentiation for muscle tissue engineering. Mass fractions of 0–80% of dMBs were tested, and 35% of dMBs in fibrin was shown to avoid fibrin shrinkage while creating macropores and promoting cell viability. This construct was referred to as “dMB35”. Fibrin without dMBs was termed “dMB0”. Microbead degradation created macropores in fibrin and improved cell viability. The percentage of live cells in dMB35 reached 91% at 16 days, higher than the 81% in dMB0 (p < 0.05). Live cell density in dMB35 was 1.6-fold that of dMB0 (p < 0.05). The encapsulated hUCMSCs proliferated, increasing the cell density by 2.6 times in dMB35 from 1 to 16 days. MTT activity for dMB35 was substantially higher than that for dMB0 at 16 days (p < 0.05). hUCMSCs in dMB35 had high gene expressions of myotube markers of myosin heavy chain 1 (MYH1) and alpha-actinin 3 (ACTN3). Elongated, multinucleated cells were formed with positive staining of myogenic specific proteins including myogenin, MYH, ACTN and actin alpha 1. Moreover, a significant increase in cell fusion was detected with myogenic induction. In conclusion, hUCMSCs were encapsulated in fibrin with degradable microbeads for the first time, achieving greatly enhanced cell viability and successful myogenic differentiation with formation of multinucleated myotubes. The injectable and macroporous fibrin–dMB–hUCMSC construct may be promising for muscle tissue engineering applications.