Uridine diphosphate galactose 4-epimerase deficiency

A case of uridine diphosphate galactose (UDP-Gal) 4-epimerase deficiency was discovered by mass screening of newborn infants. UDP-Gal 4-epimerase activity of red blood cells from the patient was found to be remarkably low, i.e., 7.5% of the level in normal controls at comparable ages. The parents showed intermediate values between those of the patient and controls. The enzyme activity in a specimen of liver tissue obtained from the patient by needle biopsy revealed a normal value. Subsequently, two other families with the condition were found by mass screening and these individuals were found to be heterozygotes.

The effects of N-substitution of chitosan and the physical form of the products on the rate of hydrolysis by chitinase from Streptomyces griseus

N-Formyl, N-chloroacetyl, N-glycyl, N-isobutyryl, and N-pentanoyl derivatives of chitosan have been prepared. N-Acetylchitosan was the derivative most susceptible to chitinase from Streptomyces griseus and lysozyme from chicken egg-white, but with respect to R in the RCOHN group were CH3 > CH3CH2 > H > CH3CH2CH2 > (CH3)2CH > NH2CH2 > CICH2. Neither enzyme hydrolysed chitosan or its N-methylene. N-benzylidene, N-benzoyl, N-nicotinyl, and N-fatty acyl (C5-C18) derivatives, and lysozyme did not hydrolyse N-butyrychitosan. N-Acetylhexanoyl-chitosans, which had d.s. ratios of approximately 0.7: approximately 0.3 and approximately 0.3: approximately 0.7, were hydrolysed at approximately 0.75 and approximately 0.004 of the rate of N-acetylchitosan (powder) by chitinase. O-Acylation of N-acylchitosans caused a decrease in the rates of hydrolysis by chitinase. N-Acetylchitosan gels were hydrolysed at 8-13 times the rate for crab-shell chitin. These results indicate that not only N- and O-substituents but also the physical form of the substrates influence the rates of hydrolysis by these enzymes.

Biting pressure measured with pressure measuring sheet

Biting pressure distribution and biting force measurements were performed with normal molars using pressure measuring sheets. The maximum biting pressure was supposed to be 700 approximately 800 kg/cm2. The maximum biting force of 6th and 7th teeth exceeded 100 kg. These values were larger than the previously reported values, and the reason was ascribed to thinner sheets used for the biting.

Permeability properties of gels and membranes derived from chitosan

A series of membranes was prepared by air-drying the thin layers of N-acyl- and N-arylidene-chitosan gels. Their flow rates of water and permeabilities of various compounds were examined. N-Acylchitosan membranes were stable in both dilute acid and alkali, but N-arylidene-chitosan membranes were unstable in dilute acid. N-Acetylchitosan membranes were stable in formic acid at room temperature for up to 7 hr. The flow rates of water through N-acetylchitosan membranes were 10.0--23.6 X 10(-3) ml/cm2min under a pressure of 3 kg/cm2, and were unchanged by the membrane thickness (12--60 micrometers). The increase of carbon numbers for N-acyl groups caused a slight decrease in the flow rates, and the flow rates were decreased by partial O-acetylation of N-acetylchitosan membranes. The flow rate of water through chitosan membranes (thickness 30--35 micrometers) was 7.1 X 10(-4) ml/cm2min, which was decreased by an increase in the membranes thickness. Low-molecular-weight compounds (MW less than 2900) passed through these membranes, but high molecular-weight compounds (MW greater than 13,000) did not pass through.

The possibility of dental applications on pressure measuring sheet

Several experiments were examined in order to apply pressure measuring sheet for clinical use, especially for biting pressure measurement. For quantitatively of biting pressure and its distribution of the sheet after biting, a color data system was effective.

[Irritative effect of aclacinomycin A on the eye mucous membrane, skin and muscle (author's transl)]

Aclacinomycin A, a new anthracycline antitumor antibiotic, was given to rabbits by single instillation or single intracutaneous injection and to guinea pigs by single subcutaneous or intramuscular injection to examine the irritative effect. Slight dilatation of blood vessel and swelling in the conjunctiva and nictitating membrane were observed in the eyes of rabbits given 1% solution. Edema in the bulbar conjunctiva, iris and cornea was histologically noted. Washing of the eyes after drug instillation prevented these damages. Subcutaneous and intracutaneous injections of 1% solution (0.2 ml) gave hyperemia, swelling and necrosis at injection site. Cellular infiltration, fibrosis and necrosis were histologically detected. Intramuscular injection of 1% solution (0.2 ml) also provided induration and swelling at injection site. Histologically cellular infiltration and necrosis were observed. These irritative effects were much slighter in administration of 0.1% solution. No change was observed with 0.01% solution.

[Cardiotoxic study of aclacinomycin A: Acute cardiotoxic effect of aclacinomycin A in hamsters (author's transl)]

The Third Department of Medicine, Tokyo Medical and Dental University Medical School The cardiotoxic effect of aclacinomycin A or adriamycin given by a single intravenous injection was evaluated in golden hamsters by electrocardiography (ECG) and electron microscopy. Aclacinomycin A caused slight ECG alterations at a dose of 75 mg/kg or 100 mg/kg such as bradycardia, Ta wave formation, ST segment depression and T wave flattening. On the other hand, adriamycin caused moderate to remarkable alterations in ECG at a dose of 3.13 mg/kg or 6.25 mg/kg, such as arrhythmia, bradycardia, auriculoventricular block, bundle branch block, ST segment changes and T wave flattening. Alterations in ultrastructure of the myocardium caused by aclacinomycin A at a dose of 25 mg/kg contained some cardiac cells with mild changes, ie, dilations of sarcoplasmic reticulum and swelling of mitochondria. At a dose of 100 mg/kg, it caused moderate to remarkable alterations such as separation of myofilaments, appearance of myelin figures, and decreases in intramitochondrial granules and glycogen particles. Adriamycin, however, gave remarkable changes even at a dose of 6.25 mg/kg which involved separation of myofilaments, lower electron-density of mitochondrial matrix, vacuolization and swelling of capillary endothelial cells. From these findings, both antibiotics may cause cardiotoxicity by similar mechanism. But aclacinomycin A affected the heart milder than adriamycin.

[Chronic toxicity of aclacinomycin A in rats (author's transl)]

Male and female Wistar rats were treated with aclacinomycin A, a new anthracycline antitumor antibiotic, at 5 dosage levels (0.08, 0.15, 0.3, 0.6 and 1.2 mg/kg/day) by daily intraperitoneal injections for 180 days for a chronic toxicity study. Recovery was also examined for 30 days after completion of the administration. Mortality was as follows: Male 5/24, female 3/24 in 0.6 mg/kg/day dose group and male 19/24, female 8/24 in 1.2 mg/kg/day dose group. Anorexia, depression of spontaneous activity and unformed feces were observed in rats in 0.6 and 1.2 mg/kg/day dose groups after day 90. Body weight gain decreased during the period. No significant change was found in rats receiving the drug at 0.3 and less mg/kg/day all through the observation period. Remarkable decreases in WBC count were noted in rats in the two highest dose groups on day 90. Autopsy findings included atrophy of the thymus and hyperemia and hemorrhage in the gastrointestinal tract and mesenteric lymph node in the animals treated at 0.6 and 1.2 mg/kg/day in the examination on day 90. Histologically, atrophy of the thymus and hyperplasia of the spleen were observed in the higher dose groups on day 90. But no remarkable abnormalities were found in histological examination on day 180. The changes in general symptom and decrease in body weight gain, which were observed during the dosing period in rats in 0.6 mg/kg/day dose group, recovered within 30 days after the drug administration was discontinued but no complete recovery of the WBC count decrease was observed.

[Cardiotoxic study of aclacinomycin A. Subacute cardiotoxicity of aclacinomycin A and its recovery in hamsters (author's transl)]

Male golden hamsters were treated with aclacinomycin A or adrianmycin by daily intraperitoneal injections for 15 consecutive days, and then allowed to be recovered for 15 days. Dose levels of aclacinomycin A and adriamycin were 1.5, 2.0 and 3.0 mg/kg, and 0.17 and 0.5 mg/kg, respectively. General toxicity, electrocardiogram (ECG), blood biochemical analysis and light microscopic and electron microscopic examinations were studied. The two drugs produced body weight loss at a dose of 3.0 mg/kg and 0.5 mg/kg, respectively. Death occurred in hamsters treated with aclacinomycin A at the highest dose (4/6 animals). In ECG study, aclacinomycin A-treated hamsters showed reversible QRS duration prolongation and T wave flattening at a dose of 1.5 or 2.0 mg/kg. Adriamycin-treated animals at a dose of 0.5 mg/kg showed R wave amplitude elevation during dosing period, and PR interval prolongation, R wave amplitude elevation and S wave amplitude reduction during recovery period. Blood biochemical analysis demonstrated reversible elevation of lactate dehydrogenase and alpha-hydroxybutyrate dehydrogenase activities in aclacinomycin A-treated hamsters at a dose of 2.0 mg/kg, and an increase in lipoperoxide in adriamycin-treated animals at a dose of 0.5 mg/kg during dosing period. Histologically, both drugs produced separation of myofilaments, swelling of mitochondria, dilation of sarcoplasmic reticulums and decreases in glycogen and lipid particles in myocardium. But aclacinomycin A-treated hamsters rarely showed these alterations after recovery period, whereas adriamycin-treated animals showed separation and necrosis of myofilaments, fibrosis of muscle fibers and formation of myelin figure even after recovery period. These results suggested that cardiotoxicity caused by aclacinomycin A was reversible and milder than that by adriamycin.

[Cardiotoxic study of aclacinomycin A. Subacute cardiotoxic effect of aclacinomycin A in rats (author's transl)]

Subacut e cardiotoxic effect of aclacinomycin A or adriamycin given by daily intraperitoneal injections for 5 days was studied in rats by electrocardiography (ECG), blood biochemical analysis, light microscopy and electron microscopy. Dose levels of aclacinomycin A and adriamycin were 4 and 8 mg/kg, and 2 and 4 mg/kg, respectively. The two drugs caused severe body weight loss at a dose of 8 mg/kg and 4 mg/kg, respectively. Aclacinomycin A-treated rats at a dose of 4 mg/kg showed slight changes in ECG, whereas adriamycin-treated rats at the same dose showed a heart rate decrease, QRS duration and QT interval prolongation and R and S waves amplitude elevation. Blood biochemical changes caused by both drugs at a dose of 4 mg/kg were increased in lipoperoxide and alpha-hydroxybutyrate dehydrogenase activity. Aclacinomycin A gave slight ultrastructural changes in some cardiac cells such as formation of myelin figure and vacuolization in mitochondria. But adriamycin caused remarkable alterations such as degeneration and destruction of mitochondria, vacuolization of sarcoplasm and disappearance of myofilaments, which were often observed near the capillaries and nuclei. These results suggest that the two antibiotics caused cardiotoxicity by a similar mechanism. However, the damage produced by aclacinomycin A was milder than that of adriamycin.

[Acute toxicity of aclacinomycin A in mice, rats and dogs (author's transl)]

New antitumor anthracycline antibiotic, aclacinomycin A was given to dd-mice and Wistar rats for acute toxicity study. The LD50 values were 29 approximately 39 mg/kg (i.v., i.p. and s.c.) and 62 approximately 69 mg/kg (p.o.) in mice, and 18 approximately 28 mg/kg (i.v., i.p. and s.c.) and 58 approximately 59 mg/kg (p.o.) in rats, respectively, which were calculated by mortality rate during a 14 day observation period. Depression of spontaneous activity, anorexia, diarrhea and slight alopecia were observed. Autopsy findings in animals killed by drug included atrophy of the thymus and spleen, and hyperemia and hemorrhage in the stomach and intestines. But no remarkable change was found in animals which survived through the observation period. Mongrel dogs were given the drug intravenously at 3, 5, 7.5, 10 and 15 mg/kg, respectively. All dogs (3/3) in the three higher dose groups and 1/3 dog in 5 mg/kg dose group died within day 0 approximately 5. Others survived more than 27 days. Depression of spontaneous activity and anorexia were found from 30 minutes to 2 hours after administration, followed by vomiting and diarrhea. Increase of GOT, GPT and LDH and decrease of WBC count were detected in dogs which died. Hyperemia and hemorrhage of the lungs, stomach and intestine were found among the groups given higher doses, whereas no significant changes were recognized among the two lower dose groups.

[Studies on the absorption, excretion and distribution of aclacinomycin A: absorption, excretion and distribution of aclacinomycin A in mice, rabbits and dogs by photometric assay (author's transl)]

An anthracycline antitumor antibiotic, aclacinomycin A, was given to mice, rabbits or dogs intravenously to study the pharmacokinetics by photometric assay based on the absorption of anthracycline ring. The drug was rapidly eliminated from the blood in these animals. Drug levels were much higher in the blood cells than in the plasma. Tissue levels in dogs were 50 approximately 100 times higher than the blood levels, which showed the drug was rapidly transferred from the blood to tissues after administration. Higher levels were observed in the lungs, spleen and lymph nodes, where the drug was present as aclacinomycin A itself and the glycoside-type metabolites that were biologically active. The active form was also detected in the pancreas, heart, thymus, bone marrow and gastrointestinal tract. In the liver and kidneys, biologically inactive aglycone-type metabolites were observed. About 2 approximately 4% of the drug given to rabbits or dogs was recovered in the urine by 72 hours after administration, in which only 10% of the excreted drug was active form in rabbits but about 65% in dogs. The rest was inactive aglycone-type metabolites that were excreted almost in the conjugated form. Biliary excretion also contributed to the total clearance of the drug. Aclacinomycin A was absorbed even by oral administration in rabbits and dogs. Tissue distribution of the drug orally given to dogs was similar to that in intravenous administration, except that higher levels of active form were detected in the gastrointestinal tract and of inactive form in the liver.

[General pharmacology of aclacinomycin A (author's transl)]

The general pharmacology of aclacinomycin A, a new antitumor antibiotic, was studied in mice, rats, guinea-pigs, frogs, rabbits and dogs. The LD50 values of aclacinomycin A were 32.5 mg/kg (i.v.), 30.1 mg/kg (i.p.), 33.9 mg/kg (s.c.) and 69.7 mg/kg (p.o.), respectively in male mice, and 28.8 mg/kg (i.v.), 21.1 mg/kg (i.p.), 26.4 mg/kg (s.c.) and 58.6 mg/kg (p.o.), respectively in male rats. Aclacinomycin A had no effect on the central nervous system except potenciation of the pentobarbital sodium-induced anesthesia in mice. The contraction of isolated heart was stimulated in frogs while slightly inhibited in rabbits at higher concentration. Transient increases in the heart rate and the blood flow of peripheral vasculature were observed but the blood pressure was slightly lowered with respiratory excitation in anesthetized rabbits and dogs. The ECG (II-lead) demonstrated slight depression of R wave amplitude and slight sinus arrhythmia in dogs. Aclacinomycin A inhibited the contraction of isolated smooth muscle and antagonized some spasmogens. It inhibited the spontaneous movement of isolated rabbit ileum and rat uterus at higher concentration, and antagonized acetylcholine, histamine, serotonin and barium chloride in the contraction of isolated guinea-pig ileum. The antagonism was competitive to oxytocin and noncompetitive to acetylcholine in rat uterus, and noncompetitive to noradrenaline in rat deferent duct. The drug showed no apparent effect on the gastrointestinal propulsion in mice and on mucous membrane of the stomach in rats. However, it depressed gastric acid secretion in rats while slightly increased bile secretion in guinea-pigs. Urine volume and urinary excretion of electrolytes (Na+, K+) decreased in rats. Vascular permeability was slightly inhibited by the drug in rabbits and mice. No hemolytic effect was shown. Aclacinomycin A showed no antigenicity in anaphylactic reaction and SCHULTZ-DALE reaction in guinea-pigs.

[Subacute toxicity of aclacinomycin A in rats (author's transl)]

Wistar rats, both male and female, were treated with aclacinomycin A at 4 dosage levels (0.375, 0.75, 1.5 and 3.0 mg/kg/day) by daily intraperitoneal injection for 30 days. Several rats died in the two higher dose groups (1.5 mg/kg/day: male 2/8 and 3.0 mg/kg: male 8/8, female 8/8. Piloerection, anorexia, depression of spontaneous activity, diarrhea and slight incontinence were observed in rats in 3.0 mg/kg/day dose group. Body weight gain decreased after day 3 in rats receiving 1.5 and 3.0 mg/kg/day. A significant decrease in the total WBC count and a slight decrease in RBC count were observed in animals of 1.5 mg/kg/day dose group which were survived for 30 days. Autopsy findings demonstrated atrophy of the thymus and spleen, and hyperemia and hemorrhage in the intestine. The atrophy of the thymus and decreased hematopoiesis in the bone marrow were histologically noted in the two highest dose groups. No cardiotoxicity was observed.

[Mechanical and dimensional properties of thermosetting resins for crown (author's transl)]

The various mechanical and dimensional properties of seven thermosetting methacrylic resins for crown and one heat-curing methacrylic resin as the control were investigated. The obtained results were as follows. 1. The water sorption, namely amount of sorption water and linear expansion by water sorption of hydrophobic poly-bis-MEPP resins were 50 to 70% of that of the control. But hydrophilic poly-EDMA resins indicated the water sorption about 1 to 1.5 times as much as the control. And a poly-UDMA resin was also hydrophilic as poly-EDMA resins, indicated about 1.3 times as much as the control. 2. The properties of poly-bis-MEPP resins were more excellent than that of poly-EDMA resins especially in the wet condition, at least were equal. 3. A poly-UDMA resin contained so-called organic composite fillers, indicated more excellent properties than other resins on hardness, abrasion resistance, linear coefficient of thermal expansion, compressive strength and bending strength in the dry condition. But, in the wet condition, some of these properties of a poly-UDMA resin were approximately equal to those of other resins.

[Thermal expansion of restorative composite resins under the dry and wet conditions (author's transl)]

Linear coefficients of thermal expansion (beta) of twelve restorative composite resins, one Bis-GMA based resin and one self-curing acrylic resin were determined in the temperature range of 4 to 60 degrees C under the dry and the wet conditions on a thermomechanical analyzer. The results were as follows. 1) The thermal expansion curves obtained were nonlinear, and the transition appeared at about 40 degrees C. 2) beta reduced with the elapse of stored time and the number of times of measuring run. It appears that these phenomena were attributable to decrease of monomer remained in each case. 3) beta under the wet condition was larger than one under the dry condition, when specimens were stored for 20 days in each condition at 37 degrees C. Values of beta for composites ranged from 16.1 to 35.3 x 10(-6)/degrees C under the dry condition and from 18.1 to 55.4 x 10(-6)/degrees C under the wet condition. 4) beta of composites varied with filler content and kinds of filler and resin used. Value of beta reduced with increase of filler content, and was lower for Bis-GMA based composite resin than for MMA based composite resin.