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K Aida

Publications and source records attributed to K Aida.

At least 91 records · Page 5Linked to original sources
PubMed1996

Amino acid sequence of a peptide with molt-inhibiting activity from the kuruma prawn Penaeus japonicus.

Six major peptides (Pej-SGP-I-VI) that belong to the CHH family have been isolated from the sinus gland extracts of the kuruma prawn Penaeus japonicus. By in vitro assay using the Y-organ of the crayfish Procambarus clarkii, Pej-SGP-IV was found to be active in inhibiting ecdysteroid synthesis. We determined the complete amino acid sequence. Pej-SGP-IV consists of 77 amino acid residues, with both free aimno- and carboxyl-termini. The sequence of Pej-SGP-IV shows considerable similarity to that of MIH of the shore crab Carcinus maenas and less similarity to Pej-SGP-III, whose sequence has been previously determined.

Amino Acid Sequence↗
PubMed1996

A mass screening device of genome by polymerase chain reaction-restriction fragment-single strand conformation polymorphism analysis.

We have developed a new genome screening method and named it as polymerase chain reaction-restriction fragment-single strand conformation polymorphism (PCR-RF-SSCP) analysis. This method consists of three steps: (1) amplification of long DNA by PCR; (2) digestion of the amplified PCR products by restriction enzyme(s) and labelling the restriction sites; (3) polyacrylamide gel electrophoresis under non-denaturating conditions (SSCP analysis) and under denaturating conditions containing 8M urea. Theoretically, this method enables us to detect even a base substitution, deletion or insertion in up to 22,000 base pairs amplified from genomic DNA by PCR in one analysis. The procedures are very simple, reproducible and require no special apparatus. This method is applicable to any genes already known and we believe that this method is very useful for mass screening of the genome.

Base Sequence↗
PubMed1996

Polymorphism of the human Ca(2+)-sensing receptor gene in Japanese individuals: no relation to non-insulin dependent diabetes mellitus.

A missense mutation in the Ca(2+)-sensing receptor (CaSR) gene was previously identified in a Japanese family with familial hypocalciuric hypercalcemia. Five members of this family with the mutation in the CaSR gene also showed abnormal glucose tolerance, whereas family members homozygous for the wildtype CaSR gene were normal in this respect. The potential relation between mutations in the CaSR gene and the incidence of diabetes mellitus was therefore investigated in 27 non-insulin dependent diabetic and 40 normal Japanese subjects. Each exon of the CaSR gene was amplified by the polymerase chain reaction and subjected to single-strand conformation polymorphism (SSCP) analysis. The region of the gene containing the sixth exon showed three distinct patterns on SSCP analysis in both diabetic patients and normal subjects. Direct sequencing of DNA revealed a T/C polymorphism in the fifth intron. The TT genotype was apparent in 59.3% of diabetic patients and in 45.0% of normal subjects. The CC genotype was present in 25.9% of diabetics and in 22.5% of normal subjects. The diabetic patients were divided into three groups on the basis of genotype for the polymorphism (TT, TC, or CC). However, there was no significant difference among the three groups with regard to the method of therapy, the incidence or severity of diabetic complications, duration or family history of disease, HbA1c level, or laboratory data. The polymorphism in the fifth intron of the CaSR gene does not therefore appear to be associated with non-insulin dependent diabetes mellitus.

Adult↗
PubMed1996

Isolation and amino acid sequence of a molt-inhibiting hormone from the American crayfish, Procambarus clarkii.

A molt-inhibiting hormone (Prc-MIH) was isolated from the sinus glands of the American crayfish, Procambarus clarkii, and its amino acid sequence was determined. It comprised 75 amino acid residues and had an amidated carboxyl terminus. The amino acid sequence was much more similar to MIH of the shore crab (Cam-MIH) than to MIH of the American lobster (Hoa-MIH).

Amino Acid Sequence↗
PubMed1996

Isolation of cDNA encoding a putative chitinase precursor in the kuruma prawn Penaeus japonicus.

Amino acid sequences of chitinases have been determined in insects, plants, yeast, and bacteria, but not in crustaceans. We searched for chitinase-encoding cDNA in the kuruma prawn Penaeus japonicus by polymerase chain reaction (PCR) amplification of hepatopancreas cDNA using degenerate oligonucleotide primers derived from the two conserved regions of known chitinases. Using a PCR product as a probe, a cDNA clone was isolated. This clone contains an open reading frame for a protein (named Pjchi-1) of 572 amino acids that exhibits sequence similarities to known chitinases, especially to a chitinase from the tobacco hornworm Manduca sexta. Transcription of the mRNA was detected in the hepatopancreas but not in epidermal tissues.

Amino Acid Sequence↗
PubMed1995

Molecular cloning of a putative Ca(2+)-sensing receptor cDNA from human kidney.

A cDNA that encodes a putative Ca(2+)-sensing receptor (HuKCaSR) was cloned from human kidney with the use of the polymerase chain reaction. The predicted HuKCaSR protein consists of 1078 amino acids and shares 93.1 and 93.8% overall identity with the bovine parathyroid Ca(2+)-sensing receptor (BoPCaR1) and rat kidney Ca(2+)-sensing receptor (RaKCaR), respectively, with least similarity in the carboxyl-terminal regions. The HuKCaSR gene was mapped by fluorescence in situ hybridization to chromosome 3q21, at which region the gene responsible for familial hypocalciuric hypercalcemia has previously been localized by genetic linkage analyses. RNA blot analysis revealed HuKCaSR mRNA in human kidney, but not in brain, lung, liver, heart, skeletal muscle, or placenta.

Amino Acid Sequence↗
PubMed1995

Effects of pinealectomy and constant light exposure on day-night changes of melatonin binding sites in the goldfish brain.

Effects of pinealectomy and constant light exposure on day-night changes of melatonin binding sites in the goldfish brain were examined. The density and affinity of binding sites were higher at mid-day than at mid-night in sham-pinealectomized goldfish under light-dark cycles. The rhythms disappeared after pinealectomy, or constant light exposure both of which abolish plasma melatonin rhythms. The effects of pinealectomy and constant light exposure were not additive. These results indicate that diel changes of melatonin binding sites in the goldfish brain are regulated by endogenous melatonin of pineal origin.

Animals↗
PubMed1995

The warm temperature acclimation-related 65-kDa protein, Wap65, in goldfish and its gene expression.

cDNAs encoding a warm temperature acclimation-related protein (Wap65) were cloned from the muscle and hepatopancreas cDNA libraries of the warm temperature-acclimated goldfish Carassius auratus, and their nucleotide sequences containing 5'- and 3'-noncoding regions together with their polyadenylation signal were determined. The deduced amino acid sequence of Wap65 was 31% homologous to rat hemopexin. However, goldfish Wap65 lacked a few possible glycosylation sites and presumed functional histidine residues, implying that it may have different functions from hemopexin. Wap65 contained a leader peptide of 30 amino acids and a mature protein region of 415 amino acids. Southern blot analysis demonstrated that the protein is expressed by a single copy gene in the goldfish haploid genome. In RNA blot analysis using isolated cDNA clones, a single transcript of about 2.0 kilobases was detected in the hepatopancreas but not in brain, muscle, or hemocytes. The abundancy of this transcript markedly increased in the hepatopancreas as a result of warm temperature acclimation. Electrophoretic analysis of plasma proteins revealed a good correlation of plasma Wap65 levels to those of the corresponding transcript in the hepatopancreas, suggesting that serum Wap65 concentrations are regulated mainly by transcript levels in the hepatopancreas via the secretion process.

Acclimatization↗
PubMed1995

Immunocytochemical localization of sGnRH and cGnRH-II in the brain of goldfish, Carassius auratus.

The immunocytochemical distribution of salmon gonadotropin-releasing hormone (sGnRH) and chicken GnRH-II (cGnRH-II) neurons in the brain of goldfish was examined using respective antisera. Salmon GnRH-immunoreactive (ir) cell bodies were localized in the area between the olfactory nerve and the olfactory bulb (the terminal nerve ganglion), the ventral telencephalon, the preoptic area, and the hypothalamus. Chicken GnRH-II-ir cell bodies were observed in the same areas as were those of sGnRH, although the number of cell bodies were fewer than those of sGnRH. In addition, chicken GnRH-II-ir cell bodies were also observed in the midbrain tegmentum where no sGnRH-ir cell bodies were found. Both sGnRH-ir and cGnRH-II-ir fibers were distributed not only in the hypothalamus and the pituitary gland but also in various brain areas from the olfactory bulb to the spinal cord. The wide distribution of GnRH-ir fibers suggests that in the goldfish, sGnRH and cGnRH-II not only regulate gonadotropin release from the pituitary gland but also function as neuromodulators in various brain regions.

Animals↗
PubMed1995

Multiple gonadotropin-releasing hormone (GnRH)-immunoreactive systems in the brain of the dwarf gourami, Colisa lalia: immunohistochemistry and radioimmunoassay.

The present study characterizes gonadotropin-releasing hormone (GnRH) neuronal groups that are located in several different brain regions by investigating GnRH molecular species and projection patterns in an anabantid fish, Colisa lalia. First, we examined the molecular species of GnRHs in extracts of the brain and the pituitary by reverse-phase high-performance liquid chromatography followed by radioimmunoassays. We found salmon GnRH (sGnRH), chicken GnRH-II (cGnRH-II), and an unfamiliar GnRH-like substance. Next, to examine the distribution of each GnRH molecule in different GnRH neuronal groups, we performed immunohistochemistry using four kinds of antisera and an antibody. Furthermore, we performed brain lesioning experiments of terminal nerve (TN) cells, the most conspicuous GnRH-immunoreactive cells in Colisa lalia. Comparisons of immunoreactive structures between TN-lesioned fish and untreated fish elucidated the projection area of each neuronal group. Three major neuronal groups were observed. TN-GnRH cells, which are located in the transitional area between the olfactory bulb and the telencephalon, showed strong sGnRH and weaker cGnRH-II immunoreactivity. TN-GnRH cells projected to wide areas of the central nervous system from the olfactory bulb to the spinal cord. The second group, located in the preoptic area, showed only sGnRH immunoreactivity and projected only to the pituitary. The third one, located in the midbrain tegmentum, exhibited strong cGnRH-II and weaker sGnRH immunoreactivity. This cell group projected mainly to brain regions posterior to the hypothalamus and the spinal cord. These different projection patterns suggest functional differentiation of each GnRH neuronal group.

Animals↗
PubMed1995

Salmon GnRH synthesis in the preoptic area and the ventral telencephalon is activated during gonadal maturation in female Masu Salmon.

Changes in salmon gonadotropin-releasing hormone (sGnRH) synthetic activity in the brain during gonadal maturation were examined by in situ hybridization in 2-year-old female masu salmon. Oncorhynchus masou. During gonadal maturation, the numbers of neurons expressing sGnRH mRNA increased in the preoptic area and the ventral telencephalon, but not in the olfactory bulbs and the terminal nerve ganglion. The numbers of silver grains per neuron also increased in the preoptic area and the ventral telencephalon. These results indicate that sGnRH has multiple physiological functions according to the location of the neurons in the brain; neurons in the preoptic area and the ventral telencephalon are involved in gonadal maturation possibly by stimulating gonadotropin synthesis and release, whereas neurons in the olfactory bulbs and the terminal nerve ganglion may have different roles.

Animals↗
PubMed1995

Short photoperiod accelerates preoptic and ventral telencephalic salmon GnRH synthesis and precocious maturation in underyearling male masu salmon.

The temporal relationship between testicular maturation and salmon gonadotropin-releasing hormone (sGnRH) mRNA expression was investigated in underyearling precocious male masu salmon, Oncorhynchus masou. Testicular maturation could be experimentally manipulated by changing the length of the light-dark photoperiod; maturation was accelerated in the short photoperiod group (8L-16D) and delayed in the long photoperiod group (16-8D). sGnRH mRNA and total silver grains in these loci in individual fish, increased with advancing testicular maturation. They were maximal in the short photoperiod group in August and in the long photoperiod group in September, when spermiation occurred. In contrast, marked changes in sGnRH synthetic activity in relation to testicular maturation were not observed in the terminal nerve ganglion or in the olfactory bulbs. sGnRH neurons in the preoptic area and the ventral telencephalon are clearly influenced by photoperiod and are involved in the control of gonadal maturation probably via gonadotropin secretion.

Animals↗
PubMed1995

Longitudinal changes in peritoneal equilibration test with or without peritonitis in children.

This study was conducted to evaluate longitudinal changes in the peritoneal equilibration test (PET) in children treated with continuous peritoneal dialysis (CPD). The effects of prolonged CPD and episodes of peritonitis on the PET were examined. PET was repeated up to five times in 12 paediatric patients who were subdivided into groups with and without peritonitis. In the peritonitis group (n = 6), the dialysate/plasma (D/P) creatinine ratio at a 4-h dwell time decreased progressively with time on CPD in five of six patients. In a comparison of the initial and final PETs performed at a mean interval of 22.8 +/- 11.6 months, the D/P creatinine ratio in the final PET was significantly lower than in the initial PET (P < 0.01). In contrast, in the non-peritonitis group (n = 6), the D/P creatinine ratio in the final PET was unchanged for 28.2 +/- 12.3 months from the initial PET. The D/Do glucose ratio at a 4-h dwell time was unchanged over time in each group. Thus, repeated PET measurements revealed that membrane permeability for creatinine was not affected by prolonged CPD itself, but decreased with time after episodes of peritonitis. Although the protocol for PET is not standardised in children, PET was useful for determining the sequential changes in peritoneal function in such patients on CPD.

Child↗
PubMed1995

Effects of season, temperature, and photoperiod on plasma melatonin rhythms in the goldfish, Carassius auratus.

Effects of season, environmental temperature, and photoperiod on plasma melatonin concentrations were studied in the goldfish, Carassius auratus. When goldfish were reared under natural conditions, melatonin levels at mid-dark exhibited seasonal changes, with higher levels obtained in June and September than in December and March. When fish were kept under light:dark (LD) cycle of 12:12 at 5, 15, or 25 degrees C during March-April, temperature-dependent increases in melatonin levels at mid-dark were observed. When animals were maintained under LD 16:8 or LD 8:16 in combination with temperature changes (5, 15, and 25 degrees C) during January-February, the duration of nocturnal elevation in melatonin was controlled by the length of the scotophase while the amplitude was influenced by environmental temperature. These results indicate that plasma melatonin profiles in the goldfish exhibit seasonal changes that are regulated by both photoperiod and temperature.

Animals↗
PubMed1995

A nuclear factor (NF2d9) that binds to the male-specific P450 (Cyp 2d-9) gene in mouse liver.

Expression of the Cyp 2d-9 (steroid 16 alpha-hydroxylase) gene in mouse liver is male specific in such Mus musculus domesticus strains as FVB/N, whereas the corresponding P450 genes in the wild mouse species Mus spretus are not sex specific in their expression. These parental differences in the gene expressions were independently inherited in F1 offspring from crosses of FVB/N and M. spretus. A 5' flanking sequence (-110CTC CTCCCTATTCCGGGCC-92) was defined as a regulatory element (named SDI-A1) for the domestic Cyp 2d-9 promoter. The nucleotide which corresponds to T at position -99 within SDI-A1 was found to be substituted with C in the wild mouse P450 genes. The placing of C at position -99 abolished the transcriptional activity of SDI-A1 in HepG2 cells as well as the binding of SDI-A1 to a nuclear factor. This factor (designated NF2d9) was purified from mouse nuclear extracts, and its cDNA cloned. The purified NF2d9 bound to SDI-A1 but not to the mutated SDI-A1 with C at position -99. The deduced amino acid sequence revealed that NF2d9 is 72 and 94% identical to mouse CP2 and human LBP-1a, respectively. NF2d9 thus belongs to the CP2 family and is the mouse homolog of human LBP-1a, which modulates human immunodeficiency virus type 1 transcription. Anti-NF2d9, which was raised against the bacterially expressed protein, supershifted the SDI-A1 complex with the liver nuclear extract. Both the bacterially expressed and in vitro-translated NF2d9 inhibited SDI-A1 complex formation, although they did not bind to SDI-A1 directly. The results, therefore, indicate that the domestic Cyp 2d-9 gene can be regulated through a specific association of NF2d9 with SDI-A1.

Amino Acid Sequence↗
PubMed1995

Familial hypocalciuric hypercalcemia associated with mutation in the human Ca(2+)-sensing receptor gene.

Familial hypocalciuric hypercalcemia (FHH) is generally characterized by lifelong hypercalcemia without hypercalciuria and is inherited in an autosomal dominant manner. Affected individuals show abnormal parathyroid and renal responses to changes in the extracellular calcium concentration. A Japanese FHH family was screened for mutations in the Ca(2+)-sensing receptor gene by the polymerase chain reaction and single strand conformation polymorphism. The proband with hypercalcemia showed an abnormal pattern in exon 1 of the gene, whereas her two sisters with normocalcemia showed a normal pattern. The consanguineous parents with borderline serum calcium concentrations showed both patterns. Nucleotide sequence analysis identified a G-->C point mutation at nucleotide 118 that resulted in the conversion of the normal codon for proline into a codon for alanine at amino acid 40 (numbered according to the bovine complementary DNA). The proband was homozygous for the mutation, and the parents were heterozygous. These results imply that this mutation in the human Ca(2+)-sensing receptor gene causes FHH and that the dosage of the gene defect determines disease phenotype.

Adult↗
PubMed1995

Two differing precursor genes for the salmon-type gonadotropin-releasing hormone exist in salmonids.

Salmon gonadotropin-releasing hormone (sGnRH) is considered to have an important role in the control of reproduction in salmonid fish. As a basis for understanding the physiological functioning of sGnRH at the molecular level, we characterized the nucleotide sequences of two types of cDNAs encoding the precursors of sGnRH in sockeye salmon (ss), Oncorhynchus nerka, by a cloning strategy based on reverse transcription-PCR. The two types of cDNAs are referred to as ss-pro-sGnRH-I and -II, and consisted of 435 and 481 bases respectively. Both precursors are predicted to contain a signal peptide, the hormone and a GnRH-associated peptide that is attached to the hormone via a Gly-Lys-Arg sequence. The presence of two types of mRNAs hybridizing with either cDNA was confirmed by Northern blot analysis of brain RNA from sockeye salmon, masu salmon, O. masou, and rainbow trout, O. mykiss. The ss-pro-sGnRH-I cDNA had 97.2% and 82.8% overall identity with sGnRH cDNA from masu salmon and putative sGnRH cDNA deduced from the gene of the Atlantic salmon, Salmo salar respectively, whereas the ss-pro-sGnRH-II cDNA had 80.0% and 91.2% overall identity with the former and the latter respectively. The nucleotide sequences of ss-sGnRH-I and -II cDNAs showed less similarity (79.3%). These results indicated that each salmonid species possesses two differing sGnRH genes. The results of Southern blot analysis using genomic DNA extracted from individuals support this evidence in sockeye salmon, masu salmon and rainbow trout.

Amino Acid Sequence↗