Determination of Protein Binding of a Highly Lipophilic Drug,Isocarbacyclin Methyl Ester (TEI-9090), Using a Polydimethylsiloxane-coated Glass Beads Assay

Abstract— An adsorption technique with polydimethylsiloxane-coated glass beads (PDMS-GB) was developed to determine the protein binding of a highly lipophilic and hydrophobic drug. The present assay method is based on the quantitative adsorption of unbound drug to the PDMS-GB. This method of batch separation in a glass assay tube has an advantage of simplicity and rapidity. To evaluate the reliability of PDMS-GB assay, we compared the protein binding of diazepam in serum in-vitro measured by ultrafiltration and PDMS-GB assay. There was no significant difference between the extent of binding measured by each method. Using PDMS-GB assay, we determined the protein binding of the prostaglandin I₂ (PGI₂) analogue isocarbacyclin methyl ester (TEI-9090), whose binding cannot be measured by commonly employed techniques (equilibrium dialysis, ultrafiltration, gel filtration or ultracentrifugation) because of a high degree of adsorption to membranes, resins or tubes. The percentage of TEI-9090 bound in human serum, 4% human serum albumin (HSA, fatty acid-free) and dog serum were ～98, ～87 and ～95%, respectively, and these values were independent of TEI-9090 concentration up to 10 ng mL^?1. The binding of isocarbacyclin (TEI-7165) to serum protein in man, dogs, rabbits and rats, determined by ultrafiltration, was also high (>90%). While the displacement of TEI-9090 and TEI-7165 binding to HSA by aspirin, salicylic acid and indomethacin was not observed, clofibric acid and free fatty acids significantly inhibited the protein binding of both compounds. These results indicate that the binding site of TEI-9090 and TEI-7165 on HSA could be identical with the possible binding site of PGI₂.     

Influence of ANP on Sympathetic Nerve Activity and Chronotropic Regulation of the Heart

Physiological Effects of ANP. hypotension caused by atrial natriuretic peptide (ANP) is often not accompanied by the anticipated increases in beart rate or sympathetic nerve activity. the sympathetic inhibitory action of ANP occurs in cardiac and noncardiac sympathetic nerves, and has been demonstrated in conscious or anesthetized animals as well as in humans. The sympathetic inhibition by ANP occurs after atropinization but is abolisbed after va-gotomy. Thus, ANP alters sympathetic nerve activity by influencing cardiopulmonary barore-ceptors, wbich in turn is mediated by vagal afferents. In addition to the effects of ANP on cardiopulmonary baroreceptors, ANP affects arterial baroreceptors. ANP dilates the ascending aorta where some of the arterial baroreceptors are located, causing resetting of these arterial baroreceptors. When ANP is microinjected into the cerebroventricle or nucleus tractus soli-tarii, it causes inhibition of sympathetic nerve activity. It has been shown tbat ANP inhibits sympathetic ganglionic transmission and augments cardiac parasympathetic effects on heart rate. Thus., ANP may play important roles in cardiovascular regulation by influencing sympathetic nerve activity and beart rate in addition to the direct vasodilating and renal effects.     

A pilot study to evaluate a new combination therapy for gastric ulcer: Helicobacter pylori eradication therapy followed by gastroprotective treatment with rebamipide

Background and Aim: Controversies remain over the need for antiulcer treatment following 1‐week eradication triple therapy for Helicobacter pylori‐positive peptic ulcers. The usefulness of combination therapy for gastric ulcers in Japanese patients, which consists of H. pylori eradication followed by gastroprotective therapy with rebamipide, was therefore evaluated. Methods: The study was conducted in 52 H. pylori‐positive patients with an endoscopically‐proven open gastric ulcer. All patients received 1‐week triple therapy (lansoprazole, amoxicillin and clarithromycin) followed by 7‐week rebamipide therapy. After completion of the combination therapy, all patients underwent evaluation of ulcer healing by endoscopy, gastric ulcer symptoms and H. pylori eradication by rapid urease test and ¹³C‐urea breath test. Results: The ulcer healing rates were 85.7% (36/42) at 8 weeks, 83.3% (30/36) in eradicated patients and 100% (6/6) in non‐eradicated patients. The overall gastrointestinal symptom‐free rate improved from 19.0% at baseline to 88.1% at 8 weeks. H. pylori was effectively eradicated in 85.7% (36/42) of patients. Conclusions: The results suggested that the combination therapy for open gastric ulcer was safe, well‐tolerated and effective. However, data from a double‐blind placebo‐controlled study is necessary to confirm these findings.     

Normal values for KL-6 in cord venous plasma of neonates

BACKGROUND: KL-6 in umbilical cord blood, including from premature infants, and perinatal factors that may affect these values have not yet been adequately discussed. The authors investigated factors affecting cord venous plasma levels of KL-6 in neonates, and to establish a normal range of values for KL-6 in neonatal cord blood. METHODS: Cord plasma levels of KL-6 were measured in 75 neonates, and statistical analysis of factors affecting these levels was performed. A normal range for cord plasma KL-6 levels was calculated by statistical analysis methods based on guidelines by the National Committee for Clinical Laboratory Standards. RESULTS: Data from a total of 75 neonates was analyzed. Gestational age ranged from 25 to 40 weeks (median, 33.4 weeks), and birthweight ranged from 776 to 3760 g (median, 1944 g). There was no statistically significant correlation between cord plasma KL-6 levels with gender, gestational age, birthweight, method of delivery, Apgar score 1 min, and postnatal respiratory distress. The normal range of values for cord plasma KL-6 was 44.3-148.2 U/mL (median, 73.0 U/mL). CONCLUSION: The cord plasma levels of KL-6 were about half the normal values reported in children and healthy adults and were not affected by various perinatal factors. The authors' findings suggest that plasma KL-6 levels rise when respiratory function is established after birth and tend to further increase with age.     

Sjogren's Syndrome With Carcinoma of the Tongue

A quite rare case of Sjögren's syndrome with squamous cellcarcinoma of the tongue was presented. Although autoimmune diseaseshowing disturbance in T and B cells tends to be associatedwith malignant tumors, and the association between Sjögren'ssyndrome and lymphoproliferative disorders is well established,the occurrence of tongue cancer together with Sjögren'ssyndrome has not, to our knowledge, been reported. The patientwas not treated with any immunosuppressive drugs other thanglucocorticoids. The association seems not to be incidental;however, there are not enough cases to warrant a valid conclusion.     

Protective effect of peroxisome proliferator activated receptor gamma agonists on diabetic and non-diabetic renal diseases

SUMMARY:   Peroxisome proliferator activated receptor gamma (PPARγ) agonist has not only antidiabetic effect but also a protective effect against various types of injury of the kidney. The protective effects of PPARγ agonists are observed in diabetic nephropathy and non-diabetic renal diseases such as 5/6 ablation model of renal failure, experimental glomerulonephritis, ischemia-reperfusion injury, hypertensive nephropathy and cyclosporin-induced renal injury. The mechanism of renoprotection by PPARγ agonist is multifactorial. Anti-fibrotic and anti-inflammatory effects, suppression of renin-angiotensin system, vascular protective effect and antiapoptotic effect were proposed.     

Immunochemical Studies on Carcinoembryonic Antigen: (1) Quantitative Determination in Carcinomatous and Noncarcinomatous Tissues

Anti-CEA serum was prepared by immunizing rabbits with a crudeCEA fraction obtained from perchloric acid soluble extractsof adenocarcinoma of the stomach. After absorption, the antiserumproved to be monospecific for CEA. With Mancini's technique,CEA concentrations in perchloric acid extracts of carcinomatousand noncarcinomatous tissues were quantitatively determinedand expressed in terms of unit/ml, equivalent to mg/ml proteinconcentration of standard CEA solution. Finally, ratios of CEAunits per mg protein (CEA/P) of tissue extract were calculated. The CEA/P ratios tended to be higher in extracts from colonic,rectal and pancreatic carcinomas than in those from gastriccarcinoma, whereas they were lower in those from primary hepatomaand lung cancer. In the same patients with cancer, the ratiosfor carcinoma tissues were remarkably higher than those forthe noncarcinomatous counterparts. However, the ratios werenot related to the histological types of cancers. Relativelyhigh ratios were also observed in diseased intestinal mucosaof colonic polyposis and Crohn's disease, as well as in partsof gastric mucosa with a marked intestinal metaplasia obtainedfrom a cancerous stomach. More studies will be required to evaluatethe significance of occurrence in precancerous changes in tissues.     

A Case of Large Nonfunctioning Adrenal Cortical Carcinoma

An autopsy case of a nonfunctioning adrenal cortical carcinomais presented and the features of 16 cases with this tumor reportedbetween 1953 and 1977 in Japan are reviewed. This tumor predominantly afflicted males and the average ageof admission was 46.5 years. A palpable mass and abdominal painwere common symptoms. The average levels of 17-KS and 17-OHCSin the urine were 8.3 mg/24 hr and 4.6 mg/24 hr, respectively.The most common sites of distant metastases were the liver andlung. It was also noted that the only available mode of treatmentwas surgery.     

Suppression of a Demand Pacemaker in the Presence of Redundant Transvenous Right Ventricular Leads

A ventricular inhibited demand cardiac pacemaker was inhibited in the presence of intimate contact between the active temporary bipolar electrode ring and a retained inactive permanent bipolar electrode tip. Electromagnetic interference effects, lack of insulation, lead breaks, and loose connections were all ruled out as the cause of pacemaker suppression.     

In Vivo Localization of Heterologous Anti-Erythrocyte Antibodies in the Rat Bone Marrow and Their Effect on the Proliferative Capacity of Immature Erythroid Cells

The in vivo localization of heterologous anti-erythrocyte antibodies in therat bone marrow was determined by the I¹³¹-labeled antibody technic. I¹³¹-labeled anti-erythrocyte antibodies localized specifically in the bone marrowindicating the presence of localizing antibody. Both the localizing antibodyand the incomplete antibody were thermostable, whereas hemolysins andhemagglutinins were thermolabile. Following an intravenous injection of antierythrocyte antibodies in rats, hemolysins and hemagglutinins were clearedrapidly from the plasma. The incomplete antibodies became attached to circulating red cells within 6 hours and red cell sensitization persisted for 1 week.The localizing antibody localized in the bone marrow within 30 minutes, leaving no activity in plasma.

The anti-erythrocyte antibodies markedly reduced the uptake of tritiatedthymidine by erythroblasts in vitro, demonstrating their inhibitory effect onthe proliferative capacity of erythroblasts.

Submitted on February 3, 1964 Accepted on May 12, 1964