Heterogeneity of mouse lymphocytes in interferon production upon influenza virus challenge in culture

Heterogeneity of mouse lymphocytes with respect to interferon production upon influenza virus challenge in culture was studied. Spleen cells produced much more interferon than thymocytes or mesenteric lymph node cells. Spleen cells mainly responsible for interferon production belonged to the hydrocortisone-sensitive population. When spleen lymphocytes were separated into seven fractions by centrifugation on a serum albumin density gradient, they were found to differ greatly in interferon producing capacity; a small fraction of intermediate density, representing a few percent or less of the total lymphocytes, produced markedly high levels of interferon.     

Interaction of the low molecular weight form of elongation factor 1 with guanine nucleotides and aminoacyl-tRNA.

A low molecular weight form of the eukaryotic polypeptide chain elongation factor 1 (EF-1α) has been extensively purified from pig liver to give an apparently homogeneous preparation, which seemed to be analogous to the bacterial elongation factor, EF-Tu (Iwasaki, K., Nagata, S., Mizumoto, K., and Kaziro, Y. (1974) J. Biol. Chem. 249, 5008). Thus, the interaction of the purified EF-1α with guanine nucleotides as well as aminoacyl-tRNA has been investigated and the following results have been obtained. (1) EF-1α when kept in the absence of glycerol lost its activity to promote the binding of aminoacylt-RNA to ribosomes though it retained the ability to bind guanine nucleotides. However, the former activity could be stabilized by the addition of 25% ($\text{v}\text{v}$) glycerol to the solution. (2) EF-1α formed a binary complex with guanine nucleotides such as GTP, GDP, 5′-guanylyl methylenediphosphonate or 5′-guanylyl imidodiphosphate. The molar ratio of EF-1α to GTP or GDP in the binary complex was shown to be 1. (3) The presence of a ternary complex containing EF-1α, GTP and aminoacyl-tRNA was demonstrated by several methods, i.e., (i) an increased heat stability of EF-1α in the presence of GTP and Phe-tRNA, (ii) a decrease in the amount of the EF-1α·GTP complex in the presence of aminoacyl-tRNA, (iii) a protection of the ester linkage of Phe-tRNA from hydrolysis at alkaline pH by the presence of both EF-1α and GTP, and (iv) the isolation of the complex by gel filtration.     

Transplacental transmission of BK virus in human.

The prevalance and distribution of BK virus antibody in women during pregnancy and the occurrence of transplacental transmission of BK virus was determined by measurement of IgM antibody in the serum. Sera were collected from 63 nonpregnant women, 71 women who had experienced spontaneous abortion, 80 in the first trimester of pregnancy and the same 80 at delivery. Umbilical cord blood was also taken at delivery. Hemagglutination inhibition (HI) tests for BK virus used the micromethod of Gardner. Results indicate that a significant level of HI antibody was present in 70% of sera from all 4 experimental groups. This showed that BK virus infection was not limited to cases of spontaneous abortion. Of the 80 pregnant mothers, 6 showed a 4-fold or greater HI antibody seroconversion to BK virus after delivery. Of these 6 seroconversion patients, sensitive antibody was detected in 3 umbilical cords. Umbilical cords of those without seroconversion had no sensitive antibody. As evidenced by 2-NE-sensitive antibody, BK virus infections were also recognized in 6 of 71 women who aborted, 4 of 80 in the first trimester of pregnancy and 2 collected after delivery. The 2-ME-sensitive antibody was not found in any of 63 samples from nonpregnant women. Data indicate that 2-ME-sensitive antibody was present only in sera of women during pregnancy and after abortion. It may be possible that BK virus persists in a latent form in many healthy women and becomes activated during pregnancy.     

Amino acid sequence of an active fragment of potato proteinase inhibitor IIa.

The complete amino acid sequence of an active fragment of potato proteinase inhibitor IIa has been established by the Edman degradation procedure and the carboxypeptidase technique. Sequence analyses were carried out on the reduced and carboxymethylated active fragment and its tryptic peptides. To aid in the alignment of some tryptic peptides, the partial sequences of two fragments obtained by selective tryptic cleavage of the reactive site peptide bond of inhibitor IIa at acidic pH, with subsequent reduction and carboxymethylation, were also analyzed. The active fragment consisted of 45 amino acid residues including 6 half-cystine residues. Degradation of the intact active fragment by subtilisin [EC 3.4.21.14.] at pH 6.5. yielded 3 cystine-containing peptides. Sequence analyses of these peptides revealed that the 3 disulfide linkages were located between Cys(10) and Cys(24), Cys(14) and Cys(35), and Cys(20) and Cys(43). The reactive site peptide bond of inhibitor IIa, a Lys-Ser bond, was located between positions 32 and 33 of the active fragment. The overall sequence of the active fragment was quite different from those of potato chymotrypsin inhibitor I (subunit A) and potato carboxypeptidase inhibitor.     

Genetic polymorphisms of blood proteins in the troops of Japanese macaques,Macaca fuscata: IV. Erythrocyte esterase polymorphism inMacaca fuscata

Genetic variation at the locus controlling A₁ band of erythrocyte esterase was found in the Japanese macaque,Macaca fuscata. Existence of four alleles,Es-A ₁ ¹ ,Es-A ₁ ² ,Es-A ₁ ³ , andEs-A ₁ ⁴ , controlling the mobility of the band and codominance relation between them were postulated. A majority of the troops examined were monomorphic inEs-A ₁ 1-1 phenotype, and the variant phenotypes were observed to occur only in Yugawara-Ihama, Arashiyama, and Koshima areas.     

Genetic polymorphisms of blood proteins in the troops of Japanese macaques,Macaca fuscata: III. Erythrocyte carbonic anhydrase polymorphism inMacaca fuscata

In order to clarify the genetic relationships between troops of Japanese macaques, the authors have been looking for the genetic variation of blood proteins by electrophoretical technique. In this work the genetic variants of erythrocyte carbonic anhydrase isozymes of 1273 blood samples from 34 troops of this species were examined. The genetic polymorphisms were observed in several troops. The variable troops of CA I were Fukushima, Takasakiyama, Kohchi, Shimane, Shodoshima I, K, and T, Kashima, Kawara, Takasakiyama A, B, and C, and Tomogashima. The variant allele found in these troops is onlyd ₂ allele, which was probably identical with that reported byTashian et al. (1971). The frequencies ofd ₂ allele in the Shodoshima and Kashima troops were very high, and this phenomenon was interpreted as being a result of the founder effect and the random fluctuation of gene frequencies in these troops.     

Carbohydrate composition of the isolated cell walls of dermatophytes

In an attempt to evaluate taxonomic character of sugar composition of dermatophytes, the purified cell walls from 13 species are analyzed on neutral sugar composition by gas liquid chromatography. The results were principally compatible with those obtained by conventional morphological examination. Neutral sugar components of dermatophytes cell walls were mannose and glucose in the ratio of 1∶2.7 for Epidermophyton and 1∶1.4 for Microsporum. There were two types in Trichophyton, in which the ratios of mannose to glucose were 1∶1.6 and 1∶3.8. The cases of Trichophyton ferrugineum and Trichophyton mentagrophytes were exceptional. The ratio of the former was 1∶1.4, which implied the relation to Microsporum group, and the ratio of the latter was 1∶2.3, which was supposed to be the intermediate of two types of Trichophyton group. Albino type cell wall of Epidermophyton floccosum was more rich in glucose than pigmented type one.     

Missing piece of top predator-based conservation: Demographic analysis of an owl population on a remote subtropical island

Top predators are frequently the target of conservation programs. Owls are such predators. However, previous studies of owls are biased to species occurring in temperate regions, whereas most owl species occur in tropical or subtropical regions and are understudied. Furthermore, owls are often endemic to islands and of unknown conservation status. Demographic data for such species are especially scarce although they are essential for initiating and promoting their conservation. As a case study of demographic analysis of owls in a tropical or subtropical area and on islands, we applied an integrated population model to 7-year monitoring data (2012–2018) of the Ryukyu Scops Owl population on Minami-daito Island, Japan. We used survival history data from 903 individuals, reproduction and sex ratio data from 213 broods, and count data of 2,526 individuals in total. Long-term averages of annual survival rates were 0.73 for adult females and 0.74 for adult males, although the sexual difference was not significant. Sex ratio estimates fluctuated annually and long-term averages were slightly skewed to males: 0.51 among fledglings, 0.54 among yearlings, and 0.52 among adults. Long-term averages of population size were estimated to be 273.4 females and 296.8 males. The long-term average of population growth rate was 0.98, suggesting a slightly declining trend. It was fortunate to recognize the declining trend during the early phase. Considering the general lack of fundamental ecological data on owls of tropical or subtropical areas and on islands, it seems likely that many endangered owl populations await conservation efforts.     

Molecular cloning of putative chloroplastic cysteine synthase in Leucaena leucocephala

Journal of Plant Research - Cysteine biosynthesis is directed by the successive commitments of serine acetyltransferase, and O-acetylserine (thiol) lyase (OASTL) compounds, which subsequently frame...