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N Saitou

Publications and source records attributed to N Saitou.

At least 55 records · Page 3Linked to original sources
PubMed1996

Extensive polymorphism of ABO blood group gene: three major lineages of the alleles for the common ABO phenotypes.

Polymorphism of the ABO blood group gene was investigated in 262 healthy Japanese donors by a polymerase chain reactions-single-strand conformation polymorphism (PCR-SSCP) method, and 13 different alleles were identified. The number of alleles identified in each group was 4 for A1 (provisionally called ABO*A101, *A102, *A103 and *A104 according to the guidelines for human gene nomenclature), 3 for B (ABO*B101, *B102 and *B103), and 6 for O (ABO*O101, *O102, *O103, *O201, *O202 and *O203). Nucleotide sequences of the amplified fragments with different SSCP patterns were determined by direct sequencing. Phylogenetic network analysis revealed that these alleles could be classified into three major lineages, *A/*O1, *B and *O2. In Japanese, *A102 and *B101 were the predominant alleles with frequencies of 83% and 97% in each group, respectively, whereas in group O, two common alleles, *O101 (43%) and *O201 (53%), were observed. These results may be useful for the establishment of ABO genotyping, and these newly described ABO alleles would be advantageous indicators for population studies.

ABO Blood-Group System↗
PubMed1996

Human pseudoautosomal boundary-like sequences: expression and involvement in evolutionary formation of the present-day pseudoautosomal boundary of human sex chromosomes.

The human genome is composed of long-range mosaic structures of G+C% (GC%), which are thought to be related to chromosome bands. We previously identified a boundary of Mb-level domains of GC% mosaic structures in the human major histocompatibility complex (MHC) and found in the domain boundary a sequence very similar to pseudoautosomal boundary (PAB) sequences of human sex chromosomes. We designated it 'PABL' and found many PABLs in the human genome. By analysis of six genomic and six transcribed PABLs, a core and consensus sequence of about 650 nt was defined; the 3'- and 5'-edges of the PABLs were strictly conserved. Northern blot analysis showed sizes of PABL transcripts to be 5-10 kb in length. Divergence time of PABLs was estimated to be 60-120 million years ago by analysis of human PABLs and PABXY1 of seven primates, and the evolutionary rates deduced showed PABLs to have been under selective constraints. A model for evolutionary formation of the present pseudoautosomal boundary was proposed by postulation of illegitimate recombination between two PABLs.

Animals↗
PubMed1995

A genetic study of 2,000-year-old human remains from Japan using mitochondrial DNA sequences.

We present nucleotide sequence data for mitochondrial DNA extracted from ancient human skeletons of the Yayoi era (ca. 2,000 BP) excavated from the Takuta-Nishibun site in northern Kyushu of Japan. Nucleotide sequence diversity showed that the Yayoi people of the Takuta-Nishibun site were not a genetically homegeneous population. This site shows a diversity in the burial style. Phylogenetic analysis indicated a statistically significant correlation between burial style and the genetic background of the Takuta-Nishibun individuals, and revealed no discrete clusterig patterns for the Yayoi individuals, for early modern Ainu, or for the Jomon people.

Anthropology↗
PubMed1995

Mitochondrial DNA sequences of various species of the genus Equus with special reference to the phylogenetic relationship between Przewalskii's wild horse and domestic horse.

The noncoding region between tRNAPro and the large conserved sequence block is the most variable region in the mammalian mitochondrial DNA D-loop region. This variable region (ca. 270 bp) of four species of Equus, including Mongolian and Japanese native domestic horses as well as Przewalskii's (or Mongolian) wild horse, were sequenced. These data were compared with our recently published Thoroughbred horse mitochondrial DNA sequences. The evolutionary rate of this region among the four species of Equus was estimated to be 2-4 x 10(-8) per site per year. Phylogenetic trees of Equus species demonstrate that Przewalskii's wild horse is within the genetic variation among the domestic horse. This suggests that the chromosome number change (probably increase) of the Przewalskii's wild horse occurred rather recently.

Animals↗
PubMed1995

[Horizontal gaze palsy due to lesion of the abducens nucleus detected with magnetic resonance imaging].

A case of unilateral horizontal gaze palsy is reported. The lesion of the abducens nucleus was clearly detected with magnetic resonance imaging. In the early stage, the adduction of the right eye and abduction of the left eye were completely limited and the vestibulo-ocular reflex was also impaired. However, during the recovery stage, the improvement of limitation of abduction was delayed compared with that of adduction. We suggest that this phenomenon is useful as a differential diagnosis between lesions of the abducens nucleus and of the paramedian pontine reticular formation.

Abducens Nerve↗
PubMed1995

Molecular phylogeny and dissemination of human T-cell lymphotropic virus type I viewed within the context of primate evolution and human migration.

A renewed interest in the emergence and evolution of the primate T-cell lymphotropic viruses has followed the discovery of genetically distinct variants of human T-cell lymphotropic virus type I (HTLV-I) in Melanesia and Australia. Phylogenetic trees based on selected regions of the gag, pol, env and pX genes of HTLV-I from widely separated geographic regions and of simian T-cell lymphotropic virus type I (STLV-I) from African and Asian catarrhines, constructed using the neighbor-joining and maximum parsimony methods, indicated that the Australo-Melanesian and cosmopolitan strains of HTLV-I have evolved along separate geographically dependent lineages, with African STLV-I strains clustering with cosmopolitan HTLV-I strains and Asian STLV-I strains diverging from the common ancestral virus before the Australo-Melanesian HTLV-I strains. When viewed within the context of non-human primate evolution and human occupation of Australia and Melanesia, the rate of molecular change of HTLV-I and STLV-I is approximately 2.5-6.8 x 10(-7) substitutions per site per year. Overall, the sequence and phylogenetic analyses are in accord with interspecies virus transmission among non-human primates, as well as between non-human primates and humans, with independent evolution of HTLV-I in Southeast Asia and in Africa, and with dissemination of HTLV-I by forced or voluntary movements of human populations. The immunosuppressive and T-cell activation properties of HTLV-I places at added risk these Australian Aboriginal and Melanesian populations, some of which are in imminent threat of infection with human immunodeficiency virus type 1.

Africa↗
PubMed1994

Genetic analysis and molecular phylogeny of simian T-cell lymphotropic virus type I: evidence for independent virus evolution in Asia and Africa.

Type C retroviruses, designated simian T-cell lymphotropic virus type I (STLV-I), have been isolated from several genera of Old World monkeys and apes, but not from New World monkeys and prosimians. To determine the genomic diversity and molecular evolution of STLV-I and to clarify their genetic relationship to human T-cell lymphotropic virus type I (HTLV-I), we enzymatically amplified, then directly sequenced selected regions of the gag, pol, env, and pX genes of STLV-I strains from Asia and Africa. STLV-I strains Si-2, Matsu, and JM86 from Japanese macaques, which exhibited sequence similarities ranging from 98.5 to 99.8% among themselves, diverged by 12.9 to 13.3% from STLV-I strain MM39-83 from a naturally infected rhesus macaque, by 9.7 to 11.2% from STLV-I strains from Africa, and by 8.8 to 11.2% from HTLV-I strains originating in Japan, India, Africa, the Caribbean, the Americas, Polynesia, and Melanesia. By contrast, the interspecies nucleotide sequence similarity among African STLV-I strains from green monkey, yellow baboon, sooty mangabey, and common chimpanzee was remarkably high, ranging from 96.9 to 97.4%, and these STLV-I strains diverged by only 2.2 to 2.8% from HTLV-I strain EL from equatorial Zaire. Phylogenetic trees constructed by using the neighbor-joining and maximum parsimony methods indicated that the Asian STLV-I strains diverged from the common ancestral virus prior to African STLV-I and cosmopolitan and Melanesian HTLV-I strains. Thus, our data are consistent with an archaic presence of STLV-I in Asia, probably predating macaque speciation, with subsequent independent virus evolution in Asia and Africa.

Africa↗
PubMed1994

Evolutionary rates of insertion and deletion in noncoding nucleotide sequences of primates.

Insertions and deletions are responsible for gaps in aligned nucleotide sequences, but they have been usually ignored when the number of nucleotide substitutions was estimated. We compared six sets of nuclear and mitochondrial noncoding DNA sequences of primates and obtained the estimates of the evolutionary rate of insertion and deletion. The maximum-parsimony principle was applied to locate insertions and deletions on a given phylogenetic tree. Deletions were about twice as frequent as insertions for nuclear DNA, and single-nucleotide insertions and deletions were the most frequent in all events. The rate of insertion and deletion was found to be rather constant among branches of the phylogenetic tree, and the rate (approximately 2.0/kb/Myr) for mitochondrial DNA was found to be much higher than that (approximately 0.2/kb/Myr) for nuclear DNA. The rates of nucleotide substitution were about 10 times higher than the rate of insertion and deletion for both nuclear and mitochondrial DNA.

Animals↗
PubMed1994

Hosenkosides F, G, H, I, J, and K, novel baccharane glycosides from the seeds of Impatiens balsamina.

From the seeds of Impatiens balsamina we have isolated six novel baccharane glycosides, hosenkosides F-K. The structures of all isolates were determined by the use of two dimensional (2D) NMR techniques (1H-1H correlation spectroscopy (COSY), heteronuclear multiple quantum coherence (HMQC), heteronuclear multiple-bond correlation (HMBC), rotating frame Overhauser enhancement spectroscopy (ROESY), total correlation spectroscopy (TOCSY)) and chemical derivatization. Hosenkosides F, H and I are hosenkol B 3-O-sambubiosido-26-O-glucoside, 3-O-sambubioside and 3,26-O-diglucoside, respectively. Hosenkoside G is hosenkol C 3-O-sambubiosido-28-O-glucoside. Hosenkosides J and K are hosenkol A 3-O-sophoroside and 3-O-sophorosido-26-O-glucosyl-28-O-glucoside, respectively.

Carbohydrate Sequence↗
PubMed1994

[Evaluation of changes in IL-6 in gynecological infections].

We administered imipenem/cilastatin sodium (IPM/CS) to patients with gynecological infections as initial treatment and evaluated changes in blood interleukin 6 (IL-6) as an infection marker. 1. The subjects consisted of 7 patients with chorioamnionitis, 4 with intrauterine infections, and 1 with subcutaneous abscess. IPM/CS (1-2 g/day) was intravenously drip infused. This therapy was markedly effective in 1 patient and effective in 11; the response rate was 100%. 2. IL-6 generally began to decrease earlier than CRP. Before drug administration, correlations were observed between IL-6 and CRP (r = 0.946) between IL-6 and elastase (r = 0.355), and between elastase and CRP (r = 0.579). During the entire course, correlations were observed between IL-6 and CRP (r = 0.581), between IL-6 and elastase (r = 0.303), and between elastase and CRP (r = 0.776). These results suggest that blood IL-6 reflects early the pathologic state and treatment effects, and is a useful infection marker in gynecological infections.

Adult↗
PubMed1994

Polymorphisms of complement component I and C1R subcomponent of C1 in nine aboriginal Taiwanese populations.

Complement component I (IF) and C1R subcomponent of C1 (C1R) types were determined by isoelectric focusing and subsequent immunoblotting techniques for 658 individuals from nine aboriginal Taiwanese populations. The frequency of the IF*A allele ranges from 0.075 (Bunun) to 0.430 (Saisiat), and a new variant allele IF*B2 was found to have polymorphic frequency in the Atayal. The frequency of the C1R*1 allele ranges from 0.410 (Yami) to 0.650 (Atayal), and the frequency of the C1R*2 allele ranges from 0.265 (Atayal) to 0.586 (Saisiat). The C1R*5 allele was found in five populations (Atayal, Bunun, Ami, Puyuma, Yami), and the C1R*9 allele was found in two populations (Tsou, Puyuma). The results indicate a remarkable degree of genetic variability among these populations. The variability may reflect long-term genetic and geographic isolation of each population.

Alleles↗
PubMed1993

Interfamilial and intrafamilial genomic diversity and molecular phylogeny of human T-cell lymphotropic virus type I from Papua New Guinea and the Solomon Islands.

To determine the interstrain genomic diversity and molecular phylogeny of the recently identified variants of human T-cell lymphotropic virus type I (HTLV-I) in Melanesia, we enzymatically amplified, then directly sequenced representative regions of the gag, pol, and env genes of HTLV-I strains from 10 members of four families, including one family from Papua New Guinea and three families from the Solomon Islands. When aligned and compared to a Japanese strain of HTLV-I (ATK), the Melanesian HTLV-I strains differed by 7.6 to 8.7% in the gag, 7.1 to 9.3% in the pol, and 7.3 to 8.2% in the env gene regions. Based on 931 nucleotides, the overall sequence divergence of the 10 Melanesian HTLV-I strains from HTLV-I ATK was 7.3 to 8.1% (68 to 75 base substitutions). The intrafamilial genetic heterogeneity among these virus strains was nil to 0.2%, while the interfamilial sequence variation between HTLV-I strains from the Solomon Islands and those from Papua New Guinea was 3.4 to 4.2%, and the genetic heterogeneity among virus strains from the three Solomon Islands families was 0.2 to 0.9%. Using the maximum parsimony and neighbor-joining methods, phylogenetic analysis indicated that the HTLV-I strains from Papua New Guinea and the Solomon Islands formed a monophyletic group and that the Melanesian and cosmopolitan strains of HTLV-I have evolved along two major geographically dependent lineages.

Base Sequence↗
PubMed1993

Seroepidemiological survey of human T-lymphotropic retrovirus among indigenous populations in Taiwan.

The prevalence of human T-lymphotropic retrovirus (HTLV) was examined in Taiwan's indigenous populations. In all, 797 healthy subjects in Taiwan including Han Chinese and nine indigenous populations (Ami, Atayal, Bunun, Saisiat, Paiwan, Puyuma, Rukai, Tsuo, and Yami) were examined for the presence of antibodies to HTLV by particle agglutination, indirect immunofluorescence and Western blot test. Two seropositive cases were found in this screening. One Saisiat male and a Han Chinese female were seropositive for HTLV. The Western blot profile indicated the virus was type-1 HTLV.

Adult↗
PubMed1993

[Clinical evaluation of flomoxef in the treatment of chorioamnionitis and changes in the fetal fibronectin level in vaginal secretion].

Flomoxef (FMOX) was administered as an initial treatment for chorioamnionitis complicating possible spontaneous abortion or premature delivery and preterm PROM (premature rupture of the membranes), and the clinical effectiveness of the drug, and the usefulness of fetal fibronectin (FFN) as a diagnostic marker of premature delivery were evaluated. 1. Clinical effects of drip infusion of FMOX (2-4 g/day) with and without tocolysis for the treatment of chorioamnionitis were evaluated in 43 patients with possible spontaneous abortion or premature delivery and those with preterm PROM (n = 43). Changes in the FFN level in the vaginal secretion were also studied in 11 patients. 2. It was possible to prevent premature delivery in 7 (26.9%) of 26 patients, and the latent period of preterm PROM was longer than 8 days in 6 (46.2%) of 13 patients. 3. The FFN level decreased slightly in patients for whom FMOX was effective, and the outcome was satisfactory in those whose FFN levels were less than 200 ng/ml. However, the outcome was poor in those whose FFN levels were higher than 1,000 ng/ml. These findings suggest that changes in the FFN level in the vaginal secretion reflect the clinical course of chorioamnionitis as do changes in CRP.

Adult↗
PubMed1992

Concerted evolution of the primate immunoglobulin alpha-gene through gene conversion.

We determined four nucleotide sequences of the hominoid immunoglobulin alpha (C alpha) genes (chimpanzee C alpha 2, gorilla C alpha 2, and gibbon C alpha 1 and C alpha 2 genes), which made possible the examination of gene conversions in all hominoid C alpha genes. The following three methods were used to detect gene conversions: 1) phenetic tree construction; 2) detection of a DNA segment with extremely low variability between duplicated C alpha genes; and 3) a site by site search of shared nucleotide changes between duplicated C alpha genes. Results obtained from method 1 indicated a concerted evolution of the duplicated C alpha genes in the human, chimpanzee, gorilla, and gibbon lineages, while results obtained from method 2 suggested gene conversions in the human, gorilla, and gibbon C alpha genes. With method 3 we identified clusters of shared nucleotide changes between duplicated C alpha genes in human, chimpanzee, gorilla, and gibbon lineages, and in their hypothetical ancestors. In the present study converted regions were identified over the entire C alpha gene region excluding a few sites in the coding region which have escaped from gene conversion. This indicates that gene conversion is a general phenomenon in evolution, that can be clearly observed in non-functional regions.

Animals↗
PubMed1991

Reconstruction of molecular phylogeny of extant hominoids from DNA sequence data.

Evolutionary distance matrices of the extant hominoids are computed from DNA sequence data, and hominoid DNA phylogenies are reconstructed by applying the neighbor-joining method to these distance matrices. The chimpanzee is clustered with the human in most of the phylogenetic trees thus obtained. The proportion of the distance between human and chimpanzee to that between human/chimpanzee and orangutan is estimated. Both mitochondrial DNA and nuclear DNA show a similar value (0.44), which is close to values derived from DNA-DNA hybridization data.

Animals↗