Molecular abnormality of human alpha1-antitrypsin variant (Pi-ZZ) associated with plasma activity deficiency

A human alpha1-antitrypsin variant protein was purified to homogeneity from homozygous variant subjects (Pi-ZZ) who had a deficiency of plasma trypsin inhibitory capacity. Molecular weight, specific trypsin inhibitory capacity, and immunologic activity of the variant protein were identical to those of normal. Amino acids, N-acetylglucosamine, and hexose contents were closely similar in the normal and variant proteins, but the sialic acid content in the variant protein was significantly lower than normal. The structural difference between the normal and the variant alpha1-antitrypsin was elucidated by fingerprinting of their tryptic peptides. Two amino acid substitutions, i.e., glutamic acid in the normal protein to lysine in the variant protein, and glutamic acid in the normal protein to glutamine in the variant protein, were found.

Studies on gamma-glutamyl transpeptidase in human and rabbit erythrocytes

Gamma-glutamyl transpeptidase transfers the gamma-glutamyl moiety of glutathione to a variety of acceptor amino acids. Through the operation of the gamma-glutamyl-cyclotransferase cycle, this enzyme has been implicated in the transport of amino acids into cells, especially the cells of the proximal tubules of kidney. It has been reported to be present in rabbit erythrocytes. However, using white cell-free preparations, we have not been able to demonstrate the presence of gamma-glutamyl transpeptidase in human or rabbit erythrocytes either by measuring the utilization of GSH or by following the formation of the product. 14C-L-methionine was used as acceptor amino acid, and the formation of gamma-glutamyl-14C-L-methionine was followed. Using similar conditions, we have been able to demonstrate the presence of gamma-glutamyl transpeptidase in human and rabbit leukocytes and in human kidney. In contrast to a previous report, we were unable to find the accumulation of 5-oxoproline, an intermediate of the gamma-glutamyl-cyclotransferase pathway in human red cells incubated in Krebs-Ringer solution. Immunologic studies demonstrated that human red cell membranes contained no protein antigenically similar to kidney gamma-glutamyl transpeptidase. Thus our studies indicated that in human and rabbit erythrocytes, the gamma-glutamyl transpeptidase-cyclotransferase pathway was not operative.

Glucose 6-phosphate dehydrogenase in rainbow trout

Electrophoretic analysis of glucose 6-phosphate dehydrogenase from liver and blood of rainbow trout revealed a complex series of bands, which could differ between fish. The partial interconvertible nature of these bands was demonstrated with enzyme that had been incompletely inactivated at pH 8.4. In a single population of 40 fish, a homozygote and a heterozygote for an electrophoretic variant allele were found. We suggest that G6PD in rainbow trout liver and blood is determinted by two alleles at a single locus, with posttranslational modification responsible for the complex electrophoretic patterns seen. The basis for this variation appears to be NADH binding to the protein molecule. Another variant and other properties of the enzyme are described.

[Clinical study of amoxicillin used in the otorhinolaryngological field (author's transl)]

The following results were obtained from oral administration of amoxicillin to 20 cases of acute otorhinolaryngological infections for 5 consecutive days; the daily dose was 1,500 mg for adult and 750mg for child. 1. Six cases with acute tonsillitis, 6 with acute pharyngolaryngitis, 5 with acute otitis media, 2 with furuncle of the nose and 1 with acute laryngitis were treated with amoxicillin. This drug was remarkably effective in 2 of 20 cases in total, effective in 15, slightly effective in 1 and non-effective in 2. 2. The sensitivity test to amoxicillin by the use of ampicillin sensitivity disk revealed that all of isolated bacteria were remarkably sensitive to amoxicillin, except one strain of Staphylococcus aureus which was moderately sensitive. 3. Side effect occurred at the rate of 25%; 4 cases of eruption and 1 of esophagitis. Other severe side effects were not observed. From the above results, amoxicillin is considered to be an effective drug for clinical application in the otorhinolaryngological field.

Some factors affecting the nitrogen sparing action of methionine and threonine in rats fed a protein free diet

It was previously reported that methionine and threonine supplementation of a protein free diet had a greater nitrogen sparing action than methionine supplementation alone. Investigated in this study were (1) effects of depletion of labile body protein on the nitrogen sparing action of methionine and threonine supplementation of a protein free diet, (2) the effects of graded levels of methionine and threonine on urinary nitrogen excretion, (3) the effect of supplementation of other amino acids to the protein free diet plus methionine and threonine on the urinary excretion of nitrogen and (4) sex differences in the nitrogen sparing action of methionine and threonine supplementation of a protein free diet. After 10 days of feeding a protein free diet to deplete the body labile proteins, nitrogen excretion in urine of female rats was significantly reduced within the first 2 days of feeding a protein free diet supplemented with methionine and threonine. After 7 days of feeding a protein free diet supplemented with methionine and threonine, nitrogen excretion was reduced when even as little as 0.0188% of each amino acid was added. The supplementation of all essential amino acids to the protein free diet did not reduce the urinary excretion of nitrogen further than the supplementation of methionine and threonine, but improved the nitrogen balance slightly. The excretion of urinary nitrogen by female rats fed the protein free diet supplemented with small amounts (0.0188%) of methionine and threonine was significantly reduced after 7 to 14 days of feeding. In males, small amounts of methionine and threonine had no significant effect at either 7 or 14 days.

Purification of human red cell glucose 6-phosphate dehydrogenase by affinity chromatography

Human glucose 6-phosphate dehydrogenase associated with NADPH was efficiently bound with agarose-bound NADP, whereas the enzyme associated with NADP was poorly bound with agarose-bound NADP. After the elimination of haemoglobin from haemolyzate by treatment with DEAE-cellulose, the enzyme was converted into the NADPH-bound form and was applied on an affinity column. The enzyme was specifically eluted from the column by NADP in the elution buffer. A homogeneous enzyme preparation was obtained in high yield.

Glucose-6-phosphate dehydrogenase variants from Italian subjects associated with severe neonatal jaundice

Screening for the G6PD deficiency was carried out at the Maternity Division of the Galliera Hospital in Genoa, Italy. Two groups of subjects with hyperbilirubinaemia of non-immunological origin were examined: (a) 302 newborn babies of Sardinian extraction (on cord blood) and (b) 201 newborn babies of south Italian ancestry (on peripheral blood). Among 503 subjects, 43 showed an enzyme deficiency; in 39 the defect was of the Mediterranean type. In one case, previously described, the enzyme was of the A- type. In the remaining cases three different variants were identified. In the present work these three cases, each with severe neonatal jaundice, are reported. Their parents originated from Calabria, from Sardinia and from Sicily. The abnormal enzymes are respectively designated as GdDcbrousse-like,, GdGallura and GdAgrigento.

Temperature-dependent transitions of the myosin-product intermediate at 10 degrees during Mn(II)-ATP hydrolysis by myosin from rabbit psoas muscle

The initial burst of Pi liberation during the hydrolysis of Mn(II)-ATP by heavy meromyosin from rabbit psoas muscle was investigated. Below 10 degrees, the initial burst of Pi liberation was inhibited by the pre-addition of ADP without any change in the steady-state activity, but it was not inhibited above 10 degrees. The burst size was about one mole per mole of heavy meromyosin. The initial burst of Pi liberation in Mg-ATP hydrolysis at 8 degrees, however, was not inhibited by the pre-addition of ADP. These results, obtained with psoas muscle heavy meromyosin, were almost the same as those obtained with heavy meromyosin from rabbit leg and back muscles (Hozumi and Tawada (1975) Biochim. Biophys. Acta 376, 1-12) and, therefore, indicate that in Mn-ATP above 10 degrees there is at the burst site a predominant myosin -product complex generated by ATP hydrolysis. Similarly, below 10 degrees there is a myosin-product complex identical with the one generated by adding ADP (and Pi) to myosin.

The detection of cross-reacting material for alpha-antitrypsin in liver extracts by acid-starch electrophoresis

Purified extracts of alpha-antitrypsin cross-reacting material (CRM) from liver of patients with MM, ZZ, and MZ phenotypes were studied by acid-starch electrophoresis and crossed immunoelectrophoresis. It is believed that CRM-M from liver is derived primarily from postmortem digested serum antitrypsin, whereas CRM-Z is a product of postmortem digested antitrypsin from hepatocytes. All extracts produced small bands of antitrypsin on the cathodal side of the gel: A single M band migrated faster than the single Z band, whereas CRM from an MZ heterozygote produced a combination of 2 mobile bands. The CRM-Z (from a ZZ phenotype) did not migrate toward the anode, in contrast to the presence of a broad plateau of antitrypsin protein with CRM-M (from an MM phenotype) or CRM-MZ. Thus, most of the CRM-Z protein could not be accounted for on routine acid-starch electrophoresis. However, an anodal peak could be seen on starch gels with CRM-Z at less acidic pH, suggesting that the anodal-migrating CRM-Z protein is denatured and loses antigenicity at lower pH.

Effect of force-feeding a valine-free diet on gastrointestinal function of rats

To study the effect of an essential amino acid deficiency on gastrointestinal functions, rats were force-fed a 10% amino acid diet devoid of valine for several days, and subsequently a complete amino acid diet. Force-feeding of the valine-free diet for a few days delayed the disappearance of dietary nitrogen from the gastrointestinal tract. ASINGLE FEEDING OF THE COMPLETE AMINO ACID DIET CONTAINING 14C-labeled amino acids or (14C)glucose to rats previously fed the valine-free diet did not improve disappearance of the nitrogen. The absorption of the dietary carbohydrate as well as dietary nitrogen was delayed after feeding the valine-free diet. In spite of the delayed disappearance of dietary 14C-labeled amino acids or (14C)glucose from the gastrointestinal tract, the incorporation of these dietary 14C-labeled amino acids into liver lipids was not different between rats fed the complete amino acid diet and those fed the valine-free diet. Under these experimental conditions, changes in disaccharidase activities in the intestinal mucosa were in parallel with changes in the disappearance of nutrients from the gastrointestinal tract.

[Traumatic aneurysm of the frontopolar artery developing after evacuation of the subdural effusion in a 6-month-old girl (author's transl)]

A 6-month-old girl developed bilateal subdural effusion after head injury. She gradually improved after the partial stripping of the membrane of the subdural effusion although postoperative tappings of the subdural fluid were necessary. Thirty nine days after the injury, she suddenly suffered from a massive intraventricular hemorrhage. A cerebral angiography showed an aneurysm arising from the proximal part of the right frontopolar artery, which had not been revealed in the previous angiograms. It was obscure whether the congenital anomaly of the arterial wall had been existed or not, but this aneurysm might be mentioned as a traumatic aneurysm and definitely developed after the treatment for the traumatic sequence. The mechanism of this aneurysmal formation was supposed that the arterial wall was initially injured by the abnormal traumatic movement of the brain underneath the falx cerebri, and teared arterial wall was further injured by the fluctuating movements of the brain caused by repeated tappings of the effused fluid. Relation of delayed posttraumatic apoplexy and ruptured posttraumatic aneurysms was also discussed, and analysis of the reported cases of the traumatic aneurysm, as well as aneurysm in the infant, was made.