Epidemiological studies on renal papillary necrosis with diabetes mellitus in Japan

Eighty-six cases of renal papillary necrosis (RPN) published in Japan over the years 1949-1980 were studied. While several hundreds cases of RPN were reported in certain European countries and the USA, only 5 cases were published in Japan up until 1960. However, the number of case reports has increased to 28 over the 5 year period of 1976-1980. The ratio of diabetics (62 cases) to nondiabetics (24 cases) is about 2.6:1 and is the same as that reported by Lauer in the USA. In diabetics, RPN was more frequently seen in females (3.4:1) and at more advanced age. Frequency of bilateral occurrence was high (47.5%). The prevalence of the association of glomerulosclerosis (75.0%) was higher than that reported by Silverman et al. in the USA (47.1%). The Incidence of the association of disturbances of consciousness (29.5%) was similar to that reported by Edmondson et al.. It was concluded that the number of cases of RPN with diabetes mellitus in Japan started to increase about 20 years later than in the USA, and that the frequency of the association between RPN and diabetic glomerulosclerosis in Japan seems to be higher than in the USA. Furthermore, it was noted that RPN was frequently associated with hyperosmolar nonketotic diabetic coma.

Corrected Version Distribution of Heterogeneous and Homologous Plasmids in Bacillus spp

A total of 75 strains (including 5 reference strains) of Bacillus amyloliquefaciens, B. cereus, B. circulans, B. licheniformis, B. megaterium, B. pumilus, B. sphaericus, B. subtilis , and B. thuringiensis and 36 species-unidentified Bacillus strains were surveyed for plasmids by cesium chloride-ethidium bromide equilibrium centrifugation of cell lysates in a study of antibiotic resistance in host cells. Of the 111 strains, 13 (including 3 reference strains) were found to harbor plasmids, and 5 of the 13 showed antibiotic resistance. This antibiotic resistance appeared not to be due to the plasmids, however, because the trait was not cured by cultivation of cells in nutrient medium containing ethidium bromide (1 μg/ml), sodium dodecyl sulfate (0.2 μg/ml), or novobiocin (1 μg/ml), except in one strain, in which kanamycin and streptomycin resistances were cured by novobiocin. One strain of B. amyloliquefaciens , S294, was found to harbor a plasmid, pFTB14, which differed from the plasmid species of classes 1 to 6 in B. subtilis and B. amyloliquefaciens , as determined by restriction analysis and DNA contour length determination. However, in DNA-DNA hybridization on a filter after Southern blotting from an agarose gel, the pFTB14 DNA hybridized with plasmids of classes 1 to 5. Three strains of B. thuringiensis each carried at least 4 to 11 plasmid species, whereas no plasmids were detected in four strains of B. cereus , which, in relation to B. thuringiensis , is closely related taxonomically and has highly homologous DNA sequences. The plasmid DNAs prepared from species other than B. subtilis and B. amyloliquefaciens did not hybridize with that of pFTB14.

Cyclic AMP may not be involved in catabolite repression in Saccharomyces cerevisiae: evidence from mutants unable to synthesize it

Yeast cells with a nonsense adenylate cyclase mutation, cyr1-3, required cyclic AMP for growth. This phenotype was suppressed by the byc1 mutation; however, cyr1-3 bcy1 cells produced no detectable level of adenylate cyclase or cyclic AMP. On induction, the bcy1 and cyr1-3 bcy1 mutant cells produced the same levels of galactokinase and alpha-D-glucosidase as did the wild-type cells and fourfold-higher levels of invertase. Since galactokinase synthesis was severely repressed by glucose in the constitutive GAL81 mutants, irrespective of the cyr1-3 bcy1 genotype, cyclic AMP may not be involved in catabolite repression.

Construction of a Bacillus subtilis cloning vehicle with heterologous DNA sequence

A cloning vehicle, pFTB91, for the Bacillus subtilis host was constructed with DNA fragments heterologous to the host chromosome. It consists of three DNA fragments: (i) chromosomal DNA of Bacillus amyloliquefaciens which complements the leuA and ilvC mutations in B. subtilis; (ii) a B. amyloliquefaciens plasmid DNA that supplies an autonomously replicating function; and (iii) a HindIII fragment of Staphylococcus aureus plasmid pTP5 that carries gene tetr, conferring the TetR phenotype. It has sufficiently low DNA homology to prevent its integration into the host chromosome in recombination-competent cells of B. subtilis. It is 9.3 kb, and approx. 10 copies are present per chromosome. The SalI and KpnI sites in the ilvC+ and tetr genes, respectively, could be used for selection of recombinant plasmids by insertional inactivation. The plasmid has unique sites for EcoRI, PstI, and XbaI.

[Fontanelle pressure in infantile hydrocephalus--with special reference to 6 cases of hydrocephalus with normal head circumference and without shunting operation]

Follow-up study on ICP was carried out in 6 cases of hydrocephalus within normal head circumference for 8-9 months after birth. There were no cases with shunting operation. Abnormal plateau-like wave was recorded in 2 cases with myelomeningocele during follow-up period. In other cases of postemeningitic hydrocephalus, almost normal baseline pressure without abnormal pressure wave was recorded and all showed favorable morbidity (function). These results showed the importance of follow-up study on ICP for 9 months after birth in cases of hydrocephalus without large head circumference and shunting operation should be recommended in cases showing abnormal pressure wave recorded during follow-up period.

Two-spored asci produced by interrupted sporulation: a novel approach to linkage analysis in yeast

Genetical analysis of two-spored asci formed by interrupted sporulation offers a novel procedure for mapping of centromere-linked genes in Saccharomyces cerevisiae. Unlike the two-spored asci encountered under normal sporulation conditions, these asci are produced by a nonrandom mechanism. They fall into three categories (+ +), (+ -) and (- -) with respect to any marker. The percentage of (+ -) asci varies directly as a function of centromere-linkage of a gene. It is observed that almost 100% asci are of the (+ -) type in case of very tightly linked genes like trp-1 and cdc-10, while in case of markers unlinked to the centromere, e.g, trp-5 and met-8, the (+ -) asci constitute 50% of the total number of asci. Other markers with varying degrees of linkage, e.g. ura-3 and lys-1 show corresponding numbers of (+ -) asci between 50% and 100% of the total asci. These findings are in contrast to the results expected from a random abortion of two spores, in which case the (+ -) asci would constitute 67% of the total number of asci irrespective of the degree of centromere linkage of a marker. The linkage-dependent segregation of markers in these new kind of two-spored asci permits a rapid and accurate estimate of centromere linkage of a gene.

Distribution of heterogeneous and homologous plasmids in Bacillus spp

A total of 75 strains (including 5 reference strains) of Bacillus amyloliquefaciens, B. cereus, B. circulans, B. licheniformis, B. megaterium, B. pumilus, B. sphaericus, B. subtilis, and B. thuringiensis and 36 species-unidentified Bacillus strains were surveyed for plasmids by cesium chloride-ethidium bromide equilibrium centrifugation of cell lysates in a study of antibiotic resistance in host cells. Of the 111 strains, 13 (including 3 reference strains) were found to harbor plasmids, and 5 of the 13 showed antibiotic resistance. This antibiotic resistance appeared not to be due to the plasmids, however, because the trait was not cured by cultivation of cells in nutrient medium containing ethidium bromide (1 microgram/ml), sodium dodecyl sulfate (0.2 micrograms/ml), or novobiocin (1 microgram/ml), except in one strain, in which kanamycin and streptomycin resistances were cured by novobiocin. One strain of B. amyloliquefaciens, S294, was found to harbor a plasmid, pFTB14, which differed from the plasmid species of classes 1 to 6 in B. subtilis and B. amyloliquefaciens, as determined by restriction analysis and DNA contour length determination. However, in DNA-DNA hybridization on a filter after Southern blotting from an agarose gel, the pFTB14 DNA hybridized with plasmids of classes 1 to 5. Three strains of B. thuringiensis each carried at least 4 to 11 plasmid species, whereas no plasmids were detected in four strains of B. cereus, which, in relation to B. thuringiensis, is closely related taxonomically and has highly homologous DNA sequences. The plasmid DNAs prepared from species other than B. subtilis and B. amyloliquefaciens did not hybridize with that of pFTB14.

Recessive mutations conferring resistance to carbon catabolite repression of galactokinase synthesis in Saccharomyces cerevisiae

A total of 37 recessive mutations showing enhanced resistance to the glucose repression of galactokinase synthesis have been isolated by a selection procedure with a GAL81 gal7 double mutant. These mutations were grouped into three different complementation classes. One class, reg1, contains mutants arising from mutations at a site close to, but complementing, the gal3 locus. The reg1 mutant also showed resistance to the glucose repression of invertase synthesis but not to that of alpha-D-glucosidase. The two other classes were identified as arising from recessive mutations at the GAL82 locus and the GAL83 locus, respectively, at which various dominant mutations were isolated previously. When in a constitutive background due to the GAL81 or gal80 mutation, the GAL82 and GAL83 mutations did not show a mutually additive effect on the resistance to glucose repression of galactokinase synthesis, while the reg1 and GAL82 (or GAL83) mutations did. Based upon the specific behavior of cells with various genotypes for the above genes in response to the concentration of galactose and glucose in the medium, we propose a model involving three independent circuits for glucose signals in the regulation of the structural genes for the galactose pathway enzymes.

Construction and Characterization of Isogenic Series of Saccharomyces cerevisiae Polyploid Strains

Tetraploid cells of Saccharomyces cerevisiae are generated spontaneously in a homothallic MAT a/ MAT α diploid population at low frequency (approximately 10 −6 per cell) through the homozygosity of mating-type alleles by mitotic recombination followed by homothallic switching of the mating-type alleles. To isolate tetraploid clones more effectively, a selection method was developed that used a dye plate containing 40 mg each of eosin Y and amaranth in synthetic nutrient agar per liter. It was possible to isolate tetraploid clones on the dye plate at a frequency of 1 to 3% among the colonies colored dark red in contrast to the light red of the original diploid colonies. Isogenic series of haploid to tetraploid clones with homozygous or heterozygous genomic configurations were easily constructed with the tetraploid strains. No significant differences in specific growth rate or fermentative rate were observed corresponding to differences in ploidy, although the haploid clones showed a higher frequency of spontaneous respiratory-deficient cells than did the others. However, a significant increment in the fermentative rate in glucose nutrient medium was observed in the hybrid strains constructed with two independent homozygous cell lines. These observations strongly suggest that the polyploid strains favored by the brewing and baking industries perform well not because of the physical increment of the cellular volume by polyploidy but because of the genetic complexity or heterosis by heterozygosity of the genome in the hybrid polyploid cells.

Two cases of portal-systemic shunts demonstrated by portal venography performed by operative cannulation of ileocolic vein

Two cases of portal-systemic shunt were presented. A 70 year-old cirrhotic female, who was suffered from mental confusion, underwent portal venography which demonstrated a large varicose vein connecting the inferior mesenteric vein with the left renal vein. The mean portal pressure was 15 cm saline. There were no esophagogastric varices. A 47 year-old cirrhotic female, who was admitted for evaluation of liver dysfunction found incidentally, underwent portal venography which revealed a dilated coronary vein connecting to the left renal vein. The portal pressure was 23 cm saline. There was no evidence of esophageal varices. Portal venography was performed through the ileocolic vein in both cases. In general, bleeding varices may develop most commonly in coronary-azygous system and less frequently in the territory of the superior and inferior mesenteric veins. On the contrary, retroperitoneal portal-systemic shunts is likely to cause hepatic encephalopathy rather than to develop bleeding varices. Thus, it is necessary to perform abdominal angiography in patients with hematochezia of unknown etiology or recurrent episodes of hepatic encephalopathy.

The occurrence of paralytic shellfish toxins in two species of xanthid crab from Suva barrier reef, Fiji Islands

Five species of crabs commonly occurring on Suva barrier reef, Fiji Islands, were tested for the presence of paralytic shellfish toxins. All 35 specimens of Atergatis floridus and all 18 specimens of Zosimus aeneus tested were lethal to mice, whilst none of 12 specimens of Carpilius maculatus, 8 of C. convexus and 10 of Eriphia sebana tested were lethal. A. floridus contained saxitoxin (55--60%), neosaxitoxin (35--40%), gonyautoxin-II (less than 5%) and a new toxin previously found in a toxic dinoflagellate, Pyrodinium bahamense var. compressa, and tentatively coded PBT (1%). Z. aeneus contained the same components, with additional trace amounts of gonyautoxin-I and III, but neosaxitoxin was the major component in this species. Comparison with the results of testing Okinawan specimens of Z. aeneus, A. floridus and Platipodia granulosa suggests that the toxin profile is specific to species.

An insertion mutation associated with constitutive expression of repressible acid phosphatase in Saccharomyces cerevisiae

The PHO83 mutation in Saccharomyces cerevisiae, which had been detected on the basis of constitutive production of repressible acid phosphatase and mapped at the end of the PHO5 locus, was analysed by Southern hybridization with cloned DNA fragments of the PHO5 gene as probe. It was shown that this mutant has a DNA insertion of about 6 kilobase pairs, probably in the 5'-noncoding region of the PHO5 gene. Production of repressible acid phosphatase by the PHO83 mutant is partially independent of the function of the PHO2 and PHO4 genes, the positive regulatory genes whose functions are indispensable for PHO5 expression. PHO83 mutants are constitutive in a and alpha cells, either haploid or diploid, but not in non-mating cells, MATa/MAT alpha or a certain sterile mutation. These observations strongly suggest that the PHO83 mutation is caused by insertion of a Ty element in the 5'-noncoding region of the PHO5 gene.

2-micrometers DNA-like plasmids in the osmophilic haploid yeast Saccharomyces rouxii

DNA plasmids were detected in two independent strains of Saccharomyces rouxii among 100 yeast strains other than Saccharomyces cerevisiae tested. The plasmids, pSR1 and pSR2, had almost the same mass (approximately 4 X 10(6) daltons) as 2-micrometers DNA of S. cerevisiae. pSR1 and pSR2 gave identical restriction maps with restriction endonucleases BamHI, EcoRI, HincII, HindIII, and XhoI, and both lacked restriction sites for PstI, SalI, and SmaI. These maps, however, differed significantly from that of S. cerevisiae 2-micrometers DNA. Restriction analysis also revealed two isomeric forms of each plasmid and suggested the presence of a pair of inverted repeat sequences in the molecules where intramolecular recombination took place. DNA-DNA hybridization between the pSR1 and pSR2 DNAs indicated significant homology between their base sequences, whereas no homology was detected between pSR1 and pJDB219, a chimeric plasmid constructed from a whole molecule of 2-micrometers DNA, plasmid pMB9, and a 1.2-kilobase DNA fragment of S. cerevisiae bearing the LEU2 gene. A chimeric plasmid constructed with pSR1 and YIp1, the larger EcoRI-SalI fragment of pBR322 ligated with a 6.1-kilobase DNA fragment of S. cerevisiae bearing the HIS3 gene, could replicate autonomously in an S. cerevisiae host and produced isomers, presumably by intramolecular recombination at the inverted repeats.

Plasma soluble fibrin monomer complexes in the development of diabetic retinopathy

To elucidate the relationship between plasma soluble fibrin monomer complexes (SFMC) and retinal or vitreous hemorrhages, 11 diabetics were studied for 15 months. The levels of SFMC in 3 out of the 11 cases were elevated prior to hemorrhages and in the other 8 cases SFMC levels were elevated after hemorrhages. With regard to fibrinogen (Fbg) concentrations, there was no significant difference between the values before and after hemorrhages. The plasma glucose levels did not change significantly during the observation. It was concluded that the SFMC level was not only an indicator of the intracapillary generation of thrombin but an important factor affecting the development of diabetic retinopathy.

Isolation and characterization of yeast mutants deficient in adenylate cyclase and cAMP-dependent protein kinase

Mutants of Saccharomyces cerevisiae that require cAMP for growth have been isolated. Some of the mutants isolated were deficient in adenylate cyclase activity and mapped at a locus, cyr1, located near the centromere of chromosome X. Growth of cells carrying the cyr1 mutation was arrested at the G1 phase of the yeast cell cycle in the absence of cAMP. The cyr1 mutation was suppressed by a secondary mutation designated bcy1. The bcy1 mutation bypassed the need for cAMP for growth. The bcy1 mutants had extremely low levels of cAMP-binding protein and cAMP-dependent protein kinase but produced a high level of cAMP-independent protein kinase. The results indicate that cAMP is an essential factor for yeast cells to proceed through the cell cycle via the activation of protein kinase.

Cyclic AMP may not be involved in catabolite repression in Saccharomyes cerevisiae: evidence from mutants capable of utilizing it as an adenine source

Mutants able to utilize 5'-AMP or cyclic AMP as the adenine source were isolated from an ade6 ade10 double mutant by ethyl methane sulfonate mutagenesis. A single amp1 mutation, primarily selected on 5'-AMP medium, confers the phenotype for utilization of exogenous 5'-AMP as the adenine source. From the ade6 ade10 amp1 triple mutant, a mutant able to utilize cyclic AMP was isolated, and the mutant phenotype was proven to be due to the simultaneous occurrence of triple mutations designated as cam1, cam2, and cam3. The cam3 mutation, but not cam1 or cam2, also confers the phenotype for utilizing 5'-AMP, the same phenotype as the amp1 mutation. All of these mutations are recessive to the respective wild-type counterparts. Cells having the ade6 ade10 amp1 cam1 cam2 cam3 genotype showed significant ability to take up exogenous cyclic AMP, whereas no differences were observed in cyclic AMP phosphodiesterase activity in comparison with that of the original strains used in the mutant isolation. Since glucose severely repressed galactokinase synthesis in the constitutive GAL81 mutant having the ade6 ade10 amp1 cam1 cam2 cam3 genotype, irrespective of the presence or absence of cyclic AMP in the medium, it was suggested that cyclic AMP is not involved in the mechanism of catabolite repression in Saccharomyces cerevisiae. It does, however, have a stimulative effect on the galactokinase synthesis in the GAL81 mutant in the absence of glucose.

Identification of the genetic locus for the structural gene and a new regulatory gene for the synthesis of repressible alkaline phosphatase in Saccharomyces cerevisiae

Two lines of evidence showed that the PHO8 gene encodes the structure of repressible, nonspecific alkaline phosphatase in Saccharomyces cerevisiae: (i) the enzyme produced by a temperature-sensitive pho8 mutant at the permissive temperature (25 degrees C) was more thermolabile than that of the wild-type strain, and (ii) the PHO8 gene showed a gene dosage effect on the enzyme activity. The pho8 locus has been mapped on chromosome IV, 8 centimorgans distal to rna3. A new mutant carrying the pho9 gene was isolated which lacks repressible alkaline phosphatase, but has the normal phenotype for the synthesis of repressible acid phosphatase. The pho9 gene segregated independently of all known pho-regulatory genes and did not show the gene dosage effect on repressible alkaline phosphatase activity. The pho9/pho9 diploid hardly sporulated and showed no commitment to intragenic recombination when it was inoculated on sporulation medium. Hence the pho9 mutant has a phenotype similar to the pep4 mutant, which was isolated as a pleiotropic mutant with reduced levels of proteinases A and B and carboxypeptidase Y. An allelism test indicated that pho9 and pep4 are allelic.

Cloning of the HIS5 gene of Saccharomyces cerevisiae by yeast transformation

A yeast DNA fragment complementing a yeast his5 mutation was cloned on a shuttle vector, YRp7, by transformation of the yeast host with plasmid DNA prepared from a gene bank constructed in the Escherichia coli host. That the DNA fragment contains the yeast HIS5 gene was confirmed by the integration of the cloned plasmid into the his5 region of the yeast chromosome. The cloned yeast HIS5 gene weakly complemented the E. coli hisC mutation and gave rise to a slow-growing E. coli transformant without addition of histidine. From the slow-growing culture, rapidly growing variants of E. coli were easily obtained by mutations either in the bacterial chromosome or in the plasmid.

Clinical progression of giant-axonal neuropathy over a twelve year period

Giant-axonal neuropathy (GAN), a chronic peripheral neuropathy with associated Central Nervous System dysfunction and tight curly hair, is described in a 17-year-old girl. Biopsies of this girl's muscle and nerve are characteristic of this condition. Her clinical course over a 12 year period characterizes a disease of a slowly progressive nature.