Split hand/split foot malformation, deafness, and mental retardation with a complex cytogenetic rearrangement involving 7q21.3

Using 98 plasma samples from cancer patients undergoing antineoplastic chemotherapy, we compared the activities of aspartate aminotransferase and alanine aminotransferase measured by two different methods, with and without the addition of pyridoxal-5'-phosphate to the assay medium. Pyridoxal-5'-phosphate caused an increase of 1 to 20 U/l in aspartate aminotransferase and alanine aminotransferase activity in 90 and 78 patient plasma samples, respectively. Increases of aspartate aminotransferase and alanine aminotransferase activity of more than 20 U/l were observed in 8 and 20 samples, respectively. In 8 cases, the increase in alanine aminotransferase activity was greater than 50 U/l, whereas a similar increase in aspartate aminotransferase activity was decreased in only 2 cases. The considerable pyridoxal-5'-phosphate activation in aminotransferase activity observed in the plasma of a significant number of patients suggests that the use of the method with pyridoxal-5'-phosphate is advisable for a correct measurement of the catalytic concentration of aminotransferases in the plasma of patients undergoing chemotherapy.     

Effects of inhibitors of the activity of poly (ADP-ribose) synthetase on the liver injury caused by ischaemia-reperfusion: a comparison with radical scavengers

1. Poly (ADP-ribose) synthetase (PARS) is a nuclear enzyme activated by strand breaks in DNA which are caused by reactive oxygen species (ROS) and peroxynitrite. Excessive activation of PARS may contribute to the hepatocyte injury caused by ROS in vitro and inhibitors of PARS activity reduce the degree of reperfusion injury of the heart, skeletal muscle and brain in vivo. Here we compared the effects of various inhibitors of the activity of PARS with those of deferoxamine (an iron chelator which prevents the generation of hydroxyl radicals) and tiron (an intracellular scavenger of superoxide anion) on the degree of hepatic injury caused by ischaemia and reperfusion of the liver in the anaesthetized rat or rabbit. 2. In the rat, ischaemia (30 or 60 min) and reperfusion (120 min) of the liver resulted in significant increases in the serum levels of aspartate aminotransferase (AST) and alanine aminotransferase (ALT) indicating the development of liver injury. Intravenous administration of the PARS inhibitors 3-aminobenzamide (3-AB, 10 mg kg(-1) or 30 mg kg(-1)), 1,5-dihydroxyisoquinoline (ISO, 1 mg kg(-1)) or 4-amino-1,8-naphthalimide (4-AN, 3 mg kg(-1)) before reperfusion did not reduce the degree of liver injury caused by ischaemia-reperfusion. 3. In contrast to the PARS inhibitors, deferoxamine (40 mg kg(-1)) or tiron (300 mg kg(-1)) significantly attenuated the rise in the serum levels of AST and ALT caused by ischaemia-reperfusion of the liver of the rat. 4. In the rabbit, the degree of liver injury caused by ischaemia (60 min) and reperfusion (120 min) was also not affected by 3-AB (10 mg kg(-1)) or ISO (1 mg kg(-1)). 5. These results support the view that the generation of oxygen-derived free radicals mediates the liver injury associated with reperfusion of the ischaemic liver by mechanism(s) which are independent of the activation of PARS.     

Primary structure and possible functions of a trypsin inhibitor of Bombyx mori

A protein with a low molecular mass of 6027 was purified from cocoon shell of silkworm, Bombyx mori. Two-dimensional polyacrylamide gel electrophoresis (2D/PAGE) resolved this protein into a single spot with pI 4.3 and Mr 6000. Amino acid sequence analysis revealed that this protein consists of 55 amino acids, six of these being cysteine residues and is highly homologous to bovine pancreatic trypsin inhibitor-type inhibitors. The 6-kDa protein is heat stable and acid stable and inhibits bovine trypsin by forming a low-dissociation complex with trypsin in a 1 : 1 molar ratio (Ki = 2.8 x 10-10), but does not alpha-chymotrypsin. This cocoon shell-associated trypsin inhibitor (CSTI) was thus concluded to belong to the bovine pancreatic trypsin inhibitor class. CSTI was developmentally regulated in the silk gland at the final stage of larval growth, and its specific distribution in the middle silk gland, an organ in which silk proteins are stored during the final larval instar, occurred before the onset of spinning. This inhibitor protects the tryptic degradation of fibroin light (L) chain in vitro. These results suggest that this trypsin inhibitor may play an important part on regulating proteolytic activity in the silk gland or protecting silk proteins from degradation during histolysis.     

Effect of pyridoxal phosphate on the activity of aminotransferases in different structure-functional regions of the rabbit brain in radiation sickness

Pyridoxal enzymes of transamination (aspartate aminotransferase, KF 2.6.1.1. and alanine aminotransferase, KF 2.6.1.2) have been studied for their activity in different departments of the rabbit brain under the effect of ionizing radiation and introduction of pyridoxal phosphate. It has been established that the effect of ionizing radiations does not evoke the change in aspartate aminotransferase and alanine aminotransferase activity in different structure-functional departments of the rabbit brain, the decrease of aminotransferases activity in the acute period of the radiation sickness being natural. Introduction of pyridoxal phosphate irradiated animals promotes relative normalization of activity of the enzymes under study.     

Phase I trial of the thymidylate synthase inhibitor AG331 as a 5-day continuous infusion

AG331 (N6-[4-(morpholinosulfonyl)benzyl]-N6-methyl-2, 6-diaminobenz-[c,d]-indole glucuronate) is a lipophilic thymidylate synthase inhibitor with activity in solid tumor models. On the basis of preclinical data supporting regimens of frequent drug administration, we performed a Phase I trial of AG331 as a 5-day continuous infusion repeated every 3 weeks. Twenty-nine patients were entered at doses ranging from 25 to 1000 mg/m2/day. The major side effects were mild to moderate fatigue, nausea, vomiting, diarrhea, and fever. At doses >/=400 mg/m2, acute reversible elevation of bilirubin, aspartate aminotransferase, alanine aminotransferase, and gamma-glutamyltranspeptidase was observed. All patients who received >/=600 mg/m2/day experienced elevated alanine aminotransferase. Elevated liver function tests were evident by day 3 of the infusion and had resolved by day 8 in the majority. This toxicity was dose limiting at 1000 mg/m2/day, at which dose two of two patients developed grade 4 reversible hyperbilirubinemia in addition to the enzyme elevations. Serum and urine samples were analyzed by a novel high-pressure liquid chromatography method for the determination of the pharmacokinetics of AG331. Over the 50-1000 mg/m2/day dose range, mean total clearance ranged from 11.6 to 30.0 liters/h/m2, and volume of distribution at steady state ranged from 279.5 to 758.7 liters/m2. These parameters were dose independent over the dose range tested. The harmonic mean terminal half-life of AG331 was 20.2 h. Less than 5% of an AG331 dose is eliminated unchanged in the urine. Both the administered dose and exposure to the drug were related to the changes in bilirubin and aminotransferase blood levels. Evidence for inhibition of thymidylate synthase was obtained at doses ranging from 100 to 1000 mg/m2 in seven patients; plasma deoxyuridine concentrations at end-infusion were 1.8-3.8-fold higher than pretreatment values. Because of the nature of toxicity on this schedule, more extensive Phase II evaluation is not recommended, although an AG331 dose of 800 mg/m2/day for 5 days is tolerable. Exploration of less frequent dose administration is under way.     

Significance of terminal rinse for rat liver preservation

A terminal rinse (TR) is standard practice in liver preservation with University of Wisconsin solution (UW) to avoid a potassium load. The fact that sodium lactobionate sucrose solution (SLS) is an effective organ preservation solution with a low potassium provided an opportunity to evaluate rat liver preservation without the TR step. Its importance was investigated in 122 rat liver preservation experiments. In study 1, UW and a hydroxyethyl starch-free, modified UW (UWm) were used for 20-hr liver preservation followed by either no TR or Ringer's lactate TR. The 1-week survival was: UW-TR, 2/14; UW-no TR, 1/6; UWm-TR, 0/6; UWm-no TR, 5/5 (P < 0.01). In study 2, livers were stored for 30 hr in SLS, UW, UWm, and UWm + chlorpromazine 5 mg/L, all without a TR. Nine of 11 rats survived 7 days after SLS, but there were no survivors in the other groups (P < 0.05). Study 3 compared no TR with TR with SLS, Ringer's lactate (RL), or a modified Carolina rinse (CRm) after 30-hr SLS preservation. Survival, serum aspartate aminotransferase and alanine aminotransferase, and histology were assessed. One-week survival of 9/11 rats in no TR was significantly better than in the other groups (3/14 in TR-SLS, 0/8 in TR-RL, and 0/14 in TR-CRm, P < 0.01). The values of aspartate aminotransferase (mean +/- SE) 3 hr after transplantation were 1862 +/- 439 U/L, 3334 +/- 817 U/L, 6591 +/- 1944 U/L, and 7028 +/- 1704 U/L, respectively, in no TR, TR-SLS, TR-RL, and TR-CRm. There were significant differences both in aspartate aminotransferase and alanine aminotransferase between no-TR and each of TR-RL and TR-CRm (P < 0.05). Liver specimens from rats killed 3 hr after OLT showed only mild injury in the no TR group and severe injury in the remaining groups. We conclude that a terminal rinse is harmful in rat liver preservation.     

Functional and structural analysis of cis-proline mutants of Escherichia coli aspartate aminotransferase

To elucidate the role of the two conserved cis-proline residues of aspartate aminotransferase (AspAT), one double and two single mutants of the enzyme from Escherichia coli (EcAspAT) were prepared: P138A, P195A and P138A/P195A in which the two prolines were replaced by alanine. The crystal structures of P195A and P138A/P195A have been determined at 2.3-2.1 A resolution. The wild-type geometry, including the cis conformation of the 194-195 peptide bond is retained upon substitution of proline 195 by alanine, whereas the trans conformation is adopted at the 137-138 peptide bond. Quite surprisingly, the replacement of each of the two prolines by alanine does not significantly affect either the activity or the stability of the protein. All the three mutants follow the same pathway as the wild type for unfolding equilibrium induced by guanidine hydrochloride [Herold, M., and Kirschner, K. (1990) Biochemistry 29, 1907-1913]. The kinetics of renaturation of P195A, where the alanine retains the wild-type cis conformation, is faster than wild type, whereas renaturation of P138A, which adopts the trans conformation, is slower. We conclude that cis-prolines seem to have been retained throughout the evolution of aspartate aminotransferase to possibly play a subtle role in directing the traffic of intermediates toward the unique structure of the native state, rather than to respond to the needs for a specific catalytic or functional role.     

Pyridoxine deficiency and postnatal development of brain aspartate and alanine aminotransferase activities, and cholesterol levels in chicks

Feeding a pyridoxine deficient diet, for 2 weeks after hatching, had no effect on post-hatching development of chick brain aspartate aminotransferase (L-aspartate:2-oxoglutarate aminotransferase, EC 2.6.1.1) activity or on cholesterol deposition in the brain, but significantly depressed the development of brain alanine aminotransferase (L-alanine:2-oxoglutarate aminotransferase, EC 2.5.1.2) activity. Feeding a pyridoxine deficient diet from 3 to 8 weeks of age had no effect on any of the three parameters studied.     

Tricarboxylic acid cycle in rat brain synaptosomes. Fluxes and interactions with aspartate aminotransferase and malate/aspartate shuttle

The flux through different segments of the tricarboxylic acid cycle was measured in rat brain synaptosomes with gas chromatography-mass spectrometry using either deuterated glutamine or [13C]aspartate. The flux between 2-oxoglutarate and oxaloacetate was estimated to be 3.14 and 4.97 nmol/min/mg protein with and without glucose, respectively. These values were 3-5-fold faster than the flux between oxaloacetate and 2-oxoglutarate (0.92 nmol/min per mg protein) measured in the presence of glucose. The pattern of intermediates labeling suggests that the overall rate-controlling reaction involves either citrate synthase or pyruvate dehydrogenase but not 2-oxoglutarate or isocitrate dehydrogenase. The enrichment in [3,3,4,4-2H4]glutamate from [2,3,3,4,4-2H5]glutamine was as rapid as in [2,3,3,4,4-2H5]glutamate, which indicates that the aspartate aminotransferase reaction is severalfold faster than the flux through the tricarboxylic acid cycle. [13C]Aspartate was rapidly converted to [13C]malate, suggesting that in intact synaptosomes aspartate entry into the mitochondrion is very slow. The finding that aspartate is taken up by mitochondria as malate, along with the observed high enrichment in [3-2H]malate (from [2,3,3,4,4-2H5]glutamine), is consistent with the substantial synaptosomal activity of the malate/aspartate shuttle.     

Tolerance of pyrazinamide in short course chemotherapy for pulmonary tuberculosis in children

BACKGROUND: This prospective study was performed to evaluate the tolerance of pyrazinamide in short course chemotherapy in children. METHODS: A total of 114 children ages 6 months to 15 years (4.5 +/- 3.4 years) with diagnosed pulmonary tuberculosis from 1985 to 1995 entered the trial. A 2-month regimen of isoniazid, rifampin and pyrazinamide, followed by rifampin and isoniazid for the remaining 4 months, was administered orally to all children. Clinical adverse effects specifically investigated were gastrointestinal disturbances, rash, signs of hepatotoxicity and arthralgias. Laboratory toxicity data (number of leukocytes, erythrocyte sedimentation rate, aspartate aminotransferase, alanine aminotransferase and serum uric acid) were collected before treatment and 1, 3 and 5 months after the beginning of chemotherapy. RESULTS: Clinical adverse effects were mild in all cases. Three children (2.6%) had fever and 5 (4.4%) had gastrointestinal disturbances. Aspartate aminotransferase and alanine aminotransferase mean values showed no differences along time and no patients had clinical signs of hepatotoxicity. Only 11 children (19.6%) showed a slight increase in alanine aminotransferase (< 194 units/l). Serum uric acid increased in 92.2% of the children compared with pretreatment values. This increase remained within the normal range in all but 9.8% of patients. There was a significant increase in uric acid mean concentrations after 1 month of therapy (from 3.7 +/- 0.7 mg/dl to 5.7 +/- 1.6 mg/dl, P < 0.05), which fell again (4.0 +/- 1.1) 1 month after pyrazinamide was stopped. There were no signs of gout or arthralgias. In no case was the treatment interrupted. CONCLUSION: The addition of pyrazinamide in chemotherapy for pulmonary tuberculosis in children was found to be safe. The slight increase in uric acid concentration during its administration had no recognized adverse consequences.     

Studies on the posterior silk gland of the silkworm Bombyx mori. VI. Distribution of microtubules in the posterior silk gland cells

There are two microtubule systems in the posterior silk gland cells. One is a radial microtubule system in which the microtubules run radially from the basal to the apical cytoplasm and in which fibroin globules (secretory granules of fibroin) and mitochondria are arranged along these microtubules, thus composing a "canal system" which is assumed to be responsible for the intracellular transport of fibroin globules. The other is a circular microtubule system in the apical cytoplasm which is composed of bundles of microtubules and microfilaments running in a circular arrangement around the glandular lumen at an interval of approximately 4 mum at the end of the fifth instar. This system is presumably concerned with secretion and/or intraluminal transport of fibroin.     

Treatment of microfilaraemia in asymptomatic brugian filariasis: the efficacy and safety of the combination of single doses of ivermectin and diethylcarbamazine

BACKGROUND: Nitric oxide (NO) seems to play an important role in modulating tissue injury during reperfusion of the liver. In this study, we have evaluated and compared the effects of FK409 (FK), a potent spontaneous NO releaser, and L-arginine in ischemia-reperfusion injury of the rat liver. METHODS: Male Sprague-Dawley rats underwent 90 min of hepatic ischemia followed by reperfusion. FK or L-arginine was used (intravenously) in two different doses for each drug (group I, 3.2 mg/kg FK; group II, 1.6 mg/kg FK; group IV, 100 mg/kg L-arginine; and group V, 300 mg/kg L-arginine). Saline was used in control animals (group III). Hepatic enzyme status, microcirculation, serum nitrite (NO2-) and nitrate (NO3-) and tissue injury score were evaluated at predetermined times. RESULTS: Serum NO2-/NO3- was elevated immediately by FK treatment dose-dependently but not by L-arginine. However, L-arginine caused late (6-24 hr) elevation of the NO metabolites dose-dependently. The elevation of serum aspartate aminotransferase and alanine aminotransferase was suppressed and hepatic microcirculation was improved in the FK-treated groups dose-dependently. L-Arginine also improved the microcirculation, but hepatic enzymes at 24 hr of reperfusion were significantly higher in group V than in the control group. These findings were well reflected by the extent of tissue injury in respective groups. CONCLUSION: FK treatment in the immediate reperfusion period improves hepatic microcirculation and confers a significant protective effect on hepatic ischemia-reperfusion injury in the rat.     

Free lysine, glycine, alanine, glutamic acid and aspartic acid reduce the glycation of human lens proteins by galactose

The amino acids lysine, glycine, alanine, glutamate and aspartate formed adducts with galactose at physiological pH and temperature as shown by incorporation of U[14C] galactose. The percentage of galactose reacting with lysine, glycine, alanine, glutamate and aspartate was 4.5 to 7.8, 7.9 to 10.8, 3.2 to 4.6, 2.8 to 4.8 and 3 to 5.2, respectively. Studies with lysine showed that the extent of glycation of the free amino acid increased with time. Incubation of lens homogenate with galactose, effected glycation of proteins. Addition of lysine in concentrations of 5 and 10 mM to equimolar concentrations of galactose decreased the glycation of lens proteins by 64% to 71%; glycine, alanine, glutamate and aspartate decreased glycation by 23 to 68%, 32 to 61%, 35 to 56% and 26 to 61% respectively. Under similar conditions, glycine reacts to a greater extent than lysine, alanine, glutamic and aspartic acids. However, lysine was more effective than glycine, alanine, aspartic and glutamic acids in decreasing glycation of lens proteins by galactose. The decrease of glycation with added lysine increased with time. In general increase of amino acid concentration rather than that of sugar augmented the decrease of glycation of lens proteins.     

Alcoholism, hepatitis B and C viral infections, and impaired liver function among Taiwanese aboriginal groups

Viral hepatitis and alcoholism prevail in four major Taiwanese aboriginal groups. To study the relative importance of the acquisition of hepatitis B virus or hepatitis C virus infection and alcoholism to the presence of impaired liver function in these groups, the authors conducted a semistructured clinical interview for alcoholism and test for seromarkers for viral hepatitis among 993 cohort members enrolled in 1990-1992 in an ongoing prospective study (Taiwan Aboriginal Study Project). The subjects' blood specimens were tested for serum alanine aminotransferase/aspartate aminotransferase levels and for the presence of hepatitis B surface antigen and anti-hepatitis C virus antibody. The prevalence of a combination of an alanine aminotransferase level of > 35 IU/liter and an aspartate aminotransferase level of > 40 IU/liter, implying impaired liver function or advanced liver disease, was 4.3% overall. Univariate and multiple logistic regression analysis showed that, rather than chronic hepatitis B virus infection, hepatitis C virus infection and alcoholism were the two dominant risk factors that signalled the risk of liver damage among these Taiwanese aborigines. In addition, these two contributing factors were able to act synergistically to cause impaired liver function.     

Clinical laboratory manifestations of exposure to background levels of dioxins in the perinatal period

The effects of exposure to low levels of dioxins in infants (intrauterine and via breast milk) were studied. In a group of 35 babies, specially selected, laboratory tests were performed in cord blood and in blood sampled at 7 days and 11 weeks of age. The outcome of these laboratory tests was related to dioxin concentrations in milk fat and cumulative dioxin intake. At 11 weeks of age, alanine aminotransferase and aspartate aminotransferase activities in plasma were significantly related to cumulative dioxin intake. A significant negative relation was found between platelet count and cumulative dioxin intake. The results of this study suggest that exposure to background levels of dioxins, both intrauterine and via breast milk, may have effects in newborns.     

Influence of diazepam and phenytoin on penicillin-induced cerebral convulsions (author''s transl)

Abnormal serum aminotransferase activities with dominance of aspartate aminotransferase over alanine aminotransferase activity, and elevated serum adenosine deaminase activity and immunoglobulin. A concentration, were commonly encountered among patients with portal cirrhosis. The full triad was present in 31 of 49 cases (63%). As isolated abnormalities, these features were not uncommon in patients with other diseases of the liver and biliary tree, but the full triad was found only in 11 of 163 such cases (6.8%). The presence of this triad in a patient with unexplained hepatomegaly is indicative of portal cirrhosis.     

Preoperative autologous donation of 6 units of blood during rh-EPO treatment

Once daily administration of Lantana camara leaves juice at different dose levels (60, 300, 600 and 1500 mg/kg/day) for 14 days in rats resulted in alterations in various haemato- and biochemical parameters. Significant increase in blood urea nitrogen was observed with the doses of 600 and 1500 mg while significant increase in the relative weights of adrenals was observed at all the four dose levels. Total proteins, globulins, absolute lymphocyte count and per cent lymphocyte count were significantly decreased with 60, 600 and 1500 mg doses while a significant hypoglycemic effect was observed with 1500 mg only. Rats treated with 1500 mg dose did not exhibit any increase in alanine aminotransferase and aspartate aminotransferase activities or the alterations in relative kidney and liver weights. In another set of experiment, once daily oral administration of 1500 mg/kg/day for 14 days significantly inhibited the granulomatous tissue formation in rats and this effect was comparable to that of cyclophosphamide (10 mg/kg/day).     

Protein kinase inhibitors attenuate cardiac swelling-induced amino acid release in the rat

Rat Langendorff heart preparations have been used to study the efflux of cardiac amino acids into coronary artery perfusates during brief (5-min) periods of exposure to hyposmotic stress (70 mM NaCl). Coronary flow rates, heart rates and intra-aortic pressures were recorded. Amino acid levels were measured by high-performance liquid chromatography. Hyposmotic stress caused marked percentage increases in taurine, glutamate and aspartate levels in the coronary perfusate, with smaller increases in phosphoethanolamine, glycine and alanine and non-significant increases in serine and glutamine. Amino acid levels declined during reperfusion with isosmotic Krebs-Henseleit bicarbonate buffer. Inhibition of protein kinase C with chelerythrine chloride (5 microM) depressed the osmotically-induced release of aspartate, glutamate, taurine and glycine. The protein tyrosine kinase inhibitor, genistein, reduced the anisosmotic efflux of aspartate, glutamate, taurine and phosphoethanolamine. Lavendustin A, another inhibitor of tyrosine kinase, depressed the osmotically evoked release of aspartate, glutamate and taurine. These studies demonstrate the involvement of protein kinase C and tyrosine kinases in the efflux of amino acids from the osmotically challenged rat heart and imply that these enzymes are involved in the mechanisms responsible for volume regulation by cardiac cells.     

A randomized trial in primary biliary cirrhosis comparing ursodeoxycholic acid in daily doses of either 10 mg/kg or 20 mg/kg. Dutch Multicentre PBC Study Group

BACKGROUND: Ursodeoxycholic acid (UDCA) prolongs transplantation-free survival in primary biliary cirrhosis (PBC). However, the optimal therapeutic dose has not been established. AIM: To compare the effects of UDCA administered in daily doses of 10 vs. 20 mg/kg on symptoms, liver biochemistry and biliary UDCA enrichment. METHODS: A 6-month multicentre randomized open controlled trial was conducted to assess the effects of an increase in the dose of UDCA to 20 mg/kg/day vs. continuation of 10 mg/kg/day for patients who had not achieved biochemical normalization during treatment for at least 6 months with the 10 mg/kg dose. Clinical and laboratory evaluations were performed at entry and at 3-month intervals. The percentage UDCA in duodenal bile was assessed at entry and at 6 months. RESULTS: Sixty-one patients were enrolled. No side-effects of UDCA were observed. Within the 20 mg/kg/day group significant decreases were found for alkaline phosphatase (- 8%; P = 0.003), aspartate aminotransferase (- 11%; P = 0.01), alanine aminotransferase (- 17%; P < 0.001), gamma-glutamyl transferase (- 34%; P < 0.001), immunoglobulin M (- 11%; P = 0.002) and cholesterol (- 8.1%; P < 0.001). In the 10 mg/kg group none of these parameters differed significantly from baseline. No significant differences between dose groups for symptom scores or serum bilirubin were found. Biliary enrichment with UDCA increased from 37% to 46% in the 20 mg/kg group (P = 0.02) while remaining stable in the 10 mg/kg group. CONCLUSIONS: Liver biochemistry improved in PBC patients receiving UDCA 20 mg/kg/day compared to a dose of 10 mg/kg/day. Both doses were equally well tolerated. These results indicate that UDCA 10 mg/kg/ day is a suboptimal dose for treating PBC.