Duplication of the caecum in a neonate simulating intussusception

A case of caecal duplication in a 36-h-old neonate is described. The patient presented with vomiting and an abdominal mass and the barium enema finding was initially suggestive of intussusception. At laparotomy a duplication cyst completely obstructing the lumen was found. This was considered to have given the radiological picture simulating intussusception.

New mutation affecting the synthesis of some membrane proteins and sporulation in Bacillus subtilis

A new mutation, mpo, which affects the synthesis of some membrane proteins and sporulation in Bacillus subtilis was identified. The mpo mutation was tightly linked to the overproduction of membrane proteins MP32 and MP18 (molecular weights of 32,000 and 18,000, respectively) and the temperature-sensitive sporulation phenotype. Genetic analysis showed that the mpo mutation maps between the spoIIIB and lys loci.

Changes in polyamine levels in various organs of Bombyx mori during its life cycle

Polyamines in various organs of larval, pupal, and moth stages of Bombyx mori, were assayed by high-performance ion-exchange chromatography and paper and thin-layer chromatography. Putrescine and spermidine were especially abundant in the silk gland, gonads, mucous gland, and sucking stomach; spermine was also present in them, but at much lower concentrations. Both norspermidine and norspermine were detected in almost all organs examined, while their precursor 1,3-diaminopropane was found only in a limited number of organs. Low concentrations of sym-homospermidine were observed in the silk gland and ovary. Cadaverine content was particularly high in the mucous gland which contained diapause eggs and the sucking stomach. Diapause eggs contained much higher levels of cadaverine than non-diapause eggs. The concentrations of most polyamines in the silk glands remained rather constant during the larval stage, and decreased markedly at the pupal stage. Polyamines in gonads, in contrast, did not decrease at the pupal stage, but putrescine, diaminopropane, and norspermidine rather increased during the pupal and moth stages.

Neuraminidase activity in human peripheral lymphocytes: its increase in chronic active liver disease

The activity of neuraminidase (sialidase) in peripheral white blood cells was measured by a fluorometric method using 4-MU NANA as a substrate. The activity in mononuclear cells, which was predominantly lymphocytes, was 2.5 times higher than that in polymorphonuclear cells (neutrophils). The former's activity was directly proportional to the number of the cells, but that of the latter was found to be suppressed by an increasing number of cells. Thus, the increased number of PMN contaminated in MNC fraction somewhat obscured neuraminidase activity affecting suppressively . The enzyme activity in MNC of 25 control subjects (15 males and 10 females) was 254 +/- 73 pmoles per hour per 10(6) cells and there was no difference between the values in males and females (233 +/- 59 vs. 284 +/- 81). The activity in 20 patients with chronic active liver disease was significantly higher than that in controls (551 +/- 135, p less than 0.01). The amount of sialic acid in MNC, which was 1.4 times more than that in PMN, revealed a tendency for a positive correlation between neuraminidase activity. A new finding of the increase of lymphocyte neuraminidase activity was introduced and its pathological significance particularly in liver disease was discussed.

Unusual polyamines in slime molds Physarum polycephalum and Dictyostelium discoideum

We analyzed the cellular contents of not only major polyamines but also minor polyamines in slime molds Physarum polycephalum and Dictyostelium discoideum. The presence of putrescine and spermidine in either plasmodia or myxamoebae of these molds as major polyamines was confirmed. In addition to these polyamines, appreciable amounts of 1,3-diaminopropane were detected in P. polycephalum and D. discoideum. Cadaverine and sym-homospermidine were detected in P. polycephalum even when the slime mold was cultured in a chemically defined growth medium. Spermine was not detected when these molds were grown in synthetic media. Other "unusual" polyamines such as norspermidine, norspermine, thermospermine, aminopropylcadaverine, and canavalmine were not detected in either mold.

Selective elevation of the N1-acetylspermidine level in human colorectal adenocarcinomas

The association of N1-acetylspermidine with human colorectal adenocarcinomas has been evaluated in this study. Free polyamines and their monoacetylated forms in adenocarcinomas, adenomas, and apparently healthy mucosae were determined using high-performance ion-exchange chromatography. The N1-acetylspermidine levels in well- and moderately differentiated adenocarcinomas were 27.30 +/- 3.13 (S.E.) (n = 99) and 22.86 +/- 3.60 (n = 22) nmol/g, wet weight, respectively. These values were significantly higher than those of benign adenomas (5.38 +/- 0.85 nmol/g, n = 31) and of control mucosae. The N1-acetylspermidine levels in control mucosae on the oral and anal side of adenocarcinomas were 5.84 +/- 1.44 (n = 57) and 7.92 +/- 2.89 (n = 50) nmol/g, respectively; no significant difference was observed between control mucosae and adenomas. The mean levels of three polyamines, putrescine, spermidine, and spermine in both adenomas and adenocarcinomas were about twice as high as those of control mucosae. The molar ratios of spermidine to spermine were significantly greater in both adenomas and adenocarcinomas than in control tissues. There was no obvious correlation between the free polyamine concentrations and the degree of malignancy of the colorectal tumors. These results suggest that the metabolism of N1-acetylspermidine in colorectal adenocarcinomas is quite different from that in adenomas and in nonneoplastic mucosae and that N1-acetylspermidine can be a promising biochemical marker of cancer in the human large intestine.

Changes in polyamine content during limb regeneration in adult Xenopus laevis

Polyamine contents in the regenerates were determined at various stages after amputation of the forelimbs of the adult female Xenopus laevis. Putrescine, spermidine, spermine, and sym-homospermidine were detected in all the specimens examined. Cadaverine was detected only in a limited number of samples. At 5 days after amputation of forelimbs, well before the formation of regenerates, the putrescine content in the stump tissues increased, followed by the increase in spermidine content. The putrescine level in the forelimb regenerates was highest between 30 and 50 days after amputation, and then decreased. The spermidine concentration in the regenerates was about 20 times greater than that in intact forelimbs all throughout the experiments. The concentration of spermine was initially lower than that of both putrescine and spermidine and further decreased soon after amputation. The concentration of sym-homospermidine was originally very low and increased slightly during regeneration. The significance of these results, with respect to the function of polyamines in forelimb regeneration of Xenopus laevis, is discussed.

Occurrence of sym-homospermidine as the major polyamine in nitrogen-fixing cyanobacteria

We analyzed the amount of polyamines in a variety of cyanobacteria including nitrogen-fixing and nonfixing species. All the cyanobacteria capable of fixing nitrogen, contained sym-homospermidine as the major polyamine. The concentration of putrescine, spermidine and spermine was extremely low in these cyanobacteria. The cyanobacteria which normally fail to fix nitrogen contained spermidine as the major polyamine, while the sym-homospermidine content was very low or under the limits of detection. Apparently there is a close relationship between the sym-homospermidine content and the ability to fix nitrogen in cyanobacteria.

Widespread occurrence of norspermidine and norspermine in eukaryotic algae

Seven phyla of eukaryotic algae were analyzed to determine their contents of diamines and polyamines. The algae examined included Rhodophyta, Pyrrophyta, Chrysophyta, Phaeophyta, Euglenophyta, Chlorophyta, and Charophyta. Both putrescine and spermidine were detected in all the algae studied, while appreciable amounts of spermine were detected only in a few species of algae. 1,3-Diaminopropane, norspermidine, and norspermine, which are chemical analogs of putrescine, spermidine, and spermine, respectively, were widely distributed in various species of algae. There was no parallelism between the distribution patterns of putrescine derivatives and those of 1,3-diaminopropane derivatives. Cadaverine and agmatine were detected in multicellular marine algae. Homospermidine was detected sporadically in some algae. The biological and phylogenetical significance of polyamines in these lower eukaryotes is discussed.

A clinical evaluation of serum alpha-1-antichymotrypsin levels in liver disease and cancers

The serum levels of alpha-1-antichymotrypsin (ACT) were studied in 168 patients with various liver diseases and cancers in conjunction with other liver function tests, serum sialic acid, AFP and CEA. The ACT levels in acute viral hepatitis and chronic hepatitis were not significantly altered compared with the normal level (220 +/- 40 microgram/ml), although the level was slightly increased or decreased temporarily during the acute phase of the former. In liver cirrhosis, the mean level was significantly lower than the normal in spite of the absence of signs of hepatic decompensation (168 +/- 51 microgram/ml, p less than 0.001). In contrast to cirrhosis, the levels were increased to various extents in 65% of cases with hepatoma, in spite of the association of liver cirrhosis in the majority of them. Much higher levels were observed in all cases of metastatic liver cancers and cancers of the pancreas and the biliary tract. The elevations were observed even in cases without the increase of AFP or CEA. Both in cirrhosis and cancers, ACT levels were not correlated with any of serum bilirubin and serum enzyme activities, but were positively correlated with the levels of plasma fibrinogen and serum sialic acid. The measurement of serum ACT level can be taken advantage of for the diagnosis and monitoring of liver cirrhosis and liver cancers, particularly of hepatoma without AFP elevation.

[A potential role of polyamines in goiter formation (author's transl)]

Changes in polyamine contents and in the activity of polyamine biosynthetic enzymes were studied in the rat thyroid. Both exogenous and endogenous TSH promptly stimulated the activity of thyroid ornithine decarboxylase (ODC) and S-adenosyl-L-methionine decarboxylase. Treatment of the animals with antithyroid drugs resulted in an increase in circulating TSH level, the activities of the enzymes and thyroidal contents of putrescine, spermidine and spermine. Theophylline, which stimulated methylthiouracil (MTU)-induced goitrogenesis without increasing circulating TSH level, increased the thyroid ODC activity. In contrast, treatment with excess iodine (KI) which induced thyroid involution without affecting circulating levels of TSH, T4 and T3, resulted in a rapid reduction in the thyroid ODC activity. The MTU-induced goiter involuted after MTU withdrawal and the thyroid ODC and polyamine contents decreased within a few days after its withdrawal. The activity of thyroid arginase was increased by MTU and decreased by T4 injection. The enzyme may have some regulatory role in polyamine biosynthesis by controlling ornithine supply. Polyamine levels were elevated in both papillary and follicular adenocarcinomas of the human thyroid. The results suggest that the measurement of thyroid polyamines may be useful for the diagnosis of carcinomas.

A possible role of arginase in the regulation of polyamine biosynthesis in the rat thyroid

Effect of chronic methylthiouracil (MTU) treatment on the thyroid arginase activity and thyroidal concentration of arginine, ornithine and other amino acids was studied in the rat. The activity of thyroid arginase increased significantly at 15 days of MTU treatment and the elevated enzyme activity was reduced to normal by L-thyroxine (T4) injection. The thyroidal concentration of polyamines was increased by MTU and decreased by T4 with the exception of spermine. The thyroidal concentration of arginine and lysine, a substrate and an inhibitor for arginase respectively decreased significantly, while that of ornithine remained unchanged after MTU treatment. T4 injected to MTU-pretreated rats restored the decreased arginine concentration to normal. These results suggest that ornithine supply for polyamine biosynthesis is regulated by the level of both arginase and lysine in the thyroid.

Paradoxical effect of perchlorate on thyroidal weight, glucose 6-phosphate dehydrogenase and polyamines in methylthiouracil-treated rats

The effect of sodium perchlorate (NaClO4) on the methylthiouracil-induced increase in the activity of thyroid glucose 6-phosphate dehydrogenase (G6PDH), ornithine decarboxylase (ODC) and polyamine contents was studied in the rat. The G6PDH activity was increased nearly three-fold by methylthiouracil (MTU) but not by ClO4- at 7 days of treatment. Perchlorate lowered the MTU-induced enzyme activity to nearly the control level, without changing circulating thyrotrophin (TSH). The anion had no inhibitory effect on G6PDH activity in vitro. The possibility that an inhibitor specific for G6PDH was generated in ClO4- - treated rat thyroids was excluded. The activity of ODC was greatly increased by both ClO4- and MTU, the increase being significant as early as on the second day of treatment. Perchlorate had no inhibitory effect on MTU-induced ODC activity in vivo but decreased total contents of spermidine and spermine in the thyroid, without affecting the concentration (nmoles/g wet weight) of the polyamines. These results suggest that ClO4- acts directly on the thyroid to suppress specifically the stimulatory effect of TSH on G6PDH activity and possibly on polyamine accumulation.

A possible role of cadaverine in the biosynthesis of polyamines in the Japanese newt testis

Polyamine content in testes of various vertebrates was studied extensively. Putrescine, spermidine and spermine were detected in all the animals examined, although the distribution pattern varied greatly from animal to animal. Cadaverine was detected only in amphibian testes; sym-homospermidine was found not only in testes but also in various other tissues of amphibians and of some reptiles. In the newt testis the concentration of cadaverine was lower than that of any other polyamines in summer, but there was a great increase in cadaverine content from autumn to winter. The testicular content of cadaverine was greater than that of other polyamines in winter. There was a gradual decrease in the cadaverine content in spring. The spermidine and spermine levels, which were rather low in winter, increased in spring and reached a peak in summer when spermatogenesis was active. The testicular concentration of putrescine that was much higher than that of spermidine or spermine throughout the year, increased only a little in summer. There was a significant negative correlation between the cadaverine levels and four other polyamine levels. Exogenous cadaverine decreased the testicular levels of putrescine. Mammalian gonadotropins decreased the cadaverine levels and increased the levels of other polyamines. A partially purified LH fraction from pituitaries of bullfrog, Rana catesbeiana, was also potent in depleting cadaverine of the testes of newts kept at 8 degrees C. These results suggest that testicular cadaverine suppresses the biosynthesis of polyamines, especially spermidine and spermine which are closely associated with spermatogenesis.

Increased alcohol dehydrogenase independent ethanol oxidation at high ethanol concentrations in isolated rat hepatocytes: the effect of chronic ethanol feeding

Rates of ethanol oxidation in isolated rat hepatocytes increased with increasing ethanol concentrations even at near-saturation of the alcohol dehydrogenase (ADH) pathway. After inhibition of ADH by pyrazole, approximately 30% of ethanol-oxidizing activity remained and this activity of the non-ADH pathway was also dependent upon ethanol concentration. The apparent Km of th non-ADH pathway for ethanol was 13 mM, which is comparable to the value for the microsomal ethanol oxidizing system. Inhibition of catalase by azide affected the activity of the non-ADH pathway by less than 10%. After chronic ethanol feeding, the rates of ethanol oxidation in isolated hepatocytes and liver slices increased significantly compared to those in pair-fed controls. This adaptive increase of ethanol oxidation was more striking at a high ethanol level (30 mM) than at a low one (10 mM). Significant differences between the two groups remained even after inhibition of ADH and catalase. The results suggest that the microsomal ethanol oxidizing system may account for the major part of the non-ADH pathway.

Abnormalities of serum cholinesterase isozyme in liver cirrhosis and hepatoma (Part II)

The pattern of serum cholinesterase (ChE) isozyme appeared to be characteristically abnormal in liver cirrhosis and hepatoma. In liver cirrhosis an abnormal fast moving peak was observed in 92.5% of fifty three patients studied. Further, diminishing activities of ChE 3 and 4, accompanied by an emergence of weak bands with unusual rates of flow, were noted in 58.5%. The latter abnormality was always associated with the former one. The pattern in hepatoma was essentially the same with liver cirrhosis, though diversity of bands was also present in some cases. It was ascertained that these abnormalities was due to sialic acid content bound to the enzyme, but was not due to production of abnormal enzyme protein moiety. It was suggested by clinical analysis that the degree of the abnormality of the isozyme may be useful for the diagnosis and prognostic evaluation of liver cirrhosis.

Separation of serum cholinesterase isozymes by an improved polyacrylamide gel electrophoresis and its application for the study of liver diseases (Part I)

A method for separation of serum (pseudo) cholinesterase isozymes was studied in order to take advantage of it for clinical research. By employing modifications on a previously reported method, analytical time was shortened to a half (1.5 days) of the original method without abolishing qualitative and quantitative accuracy. Thus, the present method facilitated its clinical application for the study of this isozyme. A normal pattern of the isozyme in Japanese in this method was determined by the analysis of sixteen normal subjects, which appeared to be very consistent in each individual under the present conditions. The distribution of relative activities of respective isozymes measured on a densitogram coincided well with that measured calorimetrically. Abnormalities of the zymogram were newly found in patients with liver cirrhosis and metastatic liver cancer, which seemed to be characteristic to the respective diseases. Isozyme patterns in the liver and ascites were also measured and compared with those in serum.

The effect of chronic ethanol consumption on pathways of ethanol metabolism

The contribution of the known hepatic pathways for the disposal of ethanol was studied utilizing two different experimental designs. In vitro studies were carried out in hepatocytes isolated from rats fed Purina chow. Rates of ethanol oxidation in these preparations increased with increasing levels of ethanol (10-50 mM). After inhibition of alcohol dehydrogenase (ADH) by pyrazole (2 mM) and the catalase by azide (1 mM) approximately 25% of the ethanol oxidizing activity remained. The residual activity was also dependent upon ethanol concentration and the apparent Km was 13 mM. Hepatocytes from ethanol-fed rats exhibited rates of ethanol oxidation which were also dependent upon the concentration of ethanol. The rates were higher in the hepatocytes from the ethanol-fed rats than in the controls. The addition of inhibitors of ADH and catalase lowered the rates, but abolished neither the differences nor the concentration dependency. In the in vivo studies, ethanol elimination rates were measured in alcohol-fed and control baboons by using a constant ethanol infusion to maintain blood ethanol at three different levels: 5, 10 or 50 mM. Ethanol elimination rate was accelerated with increasing concentration, particularly in alcohol-fed baboons. These observations indicate that a pathway other than the low Km alcohol dehydrogenase participates in alcohol oxidation and is responsible in part for the adaptive increase in ethanol metabolism associated with chronic ethanol consumption.

Demonstration of dissimilar acute haemodynamic effects of ethanol and acetaldehyde

To determine whether the acute cardiac depressant effects of ethanol could be attributed to its metabolite (acetaldehyde), either ethanol or acetaldehyde was intravenously infused into pentobarbital anaesthetised, closed-chest dogs. At a venous blood ethanol level of 199 +/- 43 (SE) mg . dl-1, ejection fraction had decreased from 35 +/- 2 to 30 +/-2%, P less than 0.05, max dP/dt/end-diastolic volume from 14.0 +/- 2.1 to 8.6 +/- 1.1 kPa . s-1 . cm-3 (105 +/- 16 to 65 +/- 8 mmHg . s-1 . cm-3), P less than 0.02, whereas end-diastolic volume (P less than 0.005), myocardial oxygen consumption (P less than 0.05) and coronary blood flow (P less than 0.005) had increased. Higher ethanol levels exaggerated these changes when peak arterial acetaldehyde was 20.2 +/- mumol . litre-1. By contrast, infusion of acetaldehyde to a peak blood level comparable with that produced by ethanol increased cardiac output from 2.4 +/- 0.2 to 2.8 +/- 0.2 litre-1 . min-1 P less than 0.01), coronary sinus oxygen saturation from 46 +/- 4 to 55 +/- 3% (P less than 0.25) and reduced systemic resistance from 8.0 +/- 0.7 to 6.3 +/- 0.5 kPa . litre-1 . min-1 (60 +/- 5 to 47 +/- 4 mmHg . litre-1 . min-1) (P less than 0.001). High dosage of acetaldehyde to a level of 129 +/- 23 mumol . litre-1 produced elevation of cardiac output (P less than 0.001), ejection fraction (P less than 0.01), coronary blood flow (P less than 0.02), whereas systemic resistance (P less than 0.001), heart rate (P less than 0.05) and myocardial oxygen consumption (P less than 0.05) decreased. Discontinuation of acetaldehyde infusion significantly reversed these changes. Max dP/dt/left ventricular end-diastolic volume and left ventricular end-diastolic volume were not significantly altered by acetaldehyde. Thus, ethanol depresses cardiac performance and increases myocardial oxygen consumption. By contrast, acetaldehyde at levels produced by ethanol metabolism improves cardiac performance, consequent to afterload reduction, and reduces myocardial oxygen consumption.

Elevated levels of polyamines and histamine in adenocarcinomas of the thyroid

The concentrations of polyamines (putrescine, spermidine, and spermine) and of histamine in normal and diseased thyroids were determined with an automated amino acid analyzer. A total of 39 specimens was investigated: 7 specimens of normal tissue, 6 adenocarcinomas, 2 specimens of tissues adjacent to adenocarcinoma, 13 specimens from treated Graves' disease, 7 follicular adenomas, 2 adenomatous goiters, and 2 specimens of Hashimoto's thyroiditis. Mean putrescine levels in tissues from normal thyroid, adenocarcinomas, Graves' disease, and follicular adenoma were 26, 143, 20, and 12 nmol/g wet tissue, respectively. The mean levels of both spermidine and spermine were slightly but significantly higher in adenocarcinomas than in other thyroid tissues. The molar ratio of spermidine to spermine was about 0.5 both in the normal and diseased thyroid tissues, except for specimens of thyroiditis. Histamine was detected in 3 of the 6 cases of thyroid carcinomas, and in case of adenomatous goiter. The data suggest that measurement of polyamines, especially putrescine, may be useful for diagnosis of thyroid adenocarcinomas.

Thyroid function and polyamines. III. Changes in ornithine decarboxylase activity and polyamine contents in the rat thyroid during hyperplasia and involution

Changes in ornithine decarboxylase (ODC) activity and in polyamine contents of the rat thyroid were studied under various experimental conditions. Methylthiouracil (MTU) treatment produced several-fold increases in the thyroid ODC activity and in the content of putrescine, spermidine and spermine within a week. While serum thyrotropin (TSH) levels increased gradually up to 3 weeks, the content of both putrescine and spermidine tended to reach a plateau after 2 weeks of the goitrogen treatment; spermine content continued to increase progressively for 3 weeks. Discontinuance of MTU at 7 days resulted in a rapid decline in the elevated thyroid ODC activity, followed by a diminution of putrescine, spermidine and RNA contents. Thyroidal putrescine, spermidine and RNA responded more sensitively to both introduction and withdrawal of TSH stimulation than thyroidal spermine and DNA. Excess iodide, having no effect on the basal level of thyroid ODC, suppressed the MTU-induced increase in this enzyme activity without affecting circulating TSH, thyroxine (T4) and triiodothyronine (T3) levels. There was a significant negative correlation between the ODC activity and intrathyroidal concentration of iodine in MTU-pretreated rats. Theophylline increased the thyroid weight and ODC activity when given to rats fed with a subeffective dose of MTU. Analyses of serum TSH, T4, T3 and of thyroidal iodine revealed that TSH-induced thyroid ODC activity was suppressed by increased circulating thyroid hormones and/or intrathyroidal iodine. Furthermore, it was suggested that thyroid hormones and excess iodide acted directly on the thyroid to alter polyamine biosynthesis, possibly by changing the responsiveness of the gland to TSH.

Metabolism of alcohol at high concentrations: role and biochemical nature of the hepatic microsomal ethanol oxidizing system

At intermediate and higher alcohol concentrations, ethanol metabolism proceeds via alcohol dehydrogenase (ADH) and the microsomal ethanol oxidizing system (MEOS), whereas catalase plays no significant role. Following prolonged ethanol consumption, an enhancement of both MEOS activity as well as the rates of ethanol metabolism occurs; the latter persisted despite inhibition of ADH by pyrazole and catalase by sodium axide, suggesting the involvement of MEOS in the adaptive increase. MEOS exhibits characteristics similar to those of other microsomal drug metabolizing enzymes and can be differentiated and isolated from both ADH and catalase activities. Reconstitution of MEOS activity was achieved with partially purified cytochrome P-450 and NADPH-cytochrome c reductase in the presence of synthetic phospholipid.

Reduction of 5'-nucleotidase activity in rat thyroid and adenohypophysis following methylthiouracil treatment

5' -Nucleotidase activity was determined in rat thyroid and some other organs employing a specific assay method. During the course of methylthiouracil (MTU) treatment, thyroid 5'-nucleotidase activity decreased significantly. This decrease was specific for this enzyme since the activity of neutral phosphatase did not change and the activity of alkaline phosphatase and Mg2+-activated adenosine triphosphatase increased markedly. The 5'-nucleotidase activity of the adenohypophysis also decreased following MTU treatment. This enzyme activity of the liver, heart and whole brain remained unchanged after the treatment. The role of this enzyme was discussed in relation to tissue growth and increased contents of RNA and DNA in the thyroid and adenohypophysis.

Thyroid function and polyamines. II. Thyrotropin stimulation of polyamine biosynthesis in the rat thyroid

Thyrotropin (TSH) injected intraperitoneally caused a significant rise in the activity of L-ornithine decarboxylase of rat thyroid within 4 hr. TSH-releasing hormone (TRH) also increased the activity of this enzyme in a dose-related manner and of putrescine-activated S-adenosyl-L-methionine decarboxylase, probably through the increased secretion of TSH from the pituitary. Administration of methylthiouracil (MTU) in the drinking water to rats resulted in an increase of these two enzymes in the thyroid. Maximal activation was observed 4 days after the initiation of MTU treatment for both enzymes. The intracellular level of putrescine and spermidine increased during the rapid phase of thyroid enlargement caused by MTU treatment. The spermine concentration, however, was relatively constant during the treatment. The RNA/DNA ratio followed a pattern very similar to that exhibited by the spermidine/spermine ratio. These results indicate that TSH stimulates the biosynthesis of polyamines by increasing the activity of the decarboxylases in the thyroid. The findings further suggest that polyamines play a role in the regulation of thyroid growth and nucleic acid metabolism.

High blood acetaldehyde levels after ethanol administration. Difference between alcoholic and nonalcoholic subjects

Blood actaldehyde and ethanol levels were measured in 11 subjects, six with chronic alcholoism and five nonalcholic controls, after alcohol had been given intravenously. Despite a progressive fall in blood ethanol over a range of 54 to 33 mM/acetaldehyde did not decrease in any of the 11 subjects. The mean acetaldehyde plateau level was significantly (p less than 0.001) higher in alcoholic (42.7 plus or minus 1.2 mum) than in nonalcoholic (26.5 plus or minus 1.5 mum) subjects. When the mean blood ethanol concentration reached 24 mM,the acetaldehyde plateau ended abruptly in each subject. The ethanol concentration at which this fall of blood acetaldehyde occurred suggests desaturation of an ethanol oxidizing system other than alcohol dehydrogenase and indicates that at high ethanol blood levels, such a system contributes to ethanol oxidation. The highet acetaldehyde levels in alcholism may result from both greater activity of this system and mitochondrial damage, and could contribut to the neurologic, hepatic and cardiac complications of alcoholism.