Biomedical subjects

M Yoshimoto

Publications and source records attributed to M Yoshimoto.

At least 19 recordsLinked to original sources

PubMed1992

Visual and infrared input to the same dendrite in the tectum opticum of the python, Python regius: electron-microscopic evidence.

In snakes with infrared receptors, the optic tectum receives input from both the visual and the infrared senses. We investigated the infrared and optic fiber terminations in the tectum with a combination of horseradish peroxidase and degeneration labeling. In addition to synapses by visual and infrared fibers onto individual neurons, we were able to observe for the first time visual and infrared synapses on one and the same dendrite.

Animals↗

PubMed1992

Molecular evolution of human paramyxoviruses. Nucleotide sequence analyses of the human parainfluenza type 1 virus NP and M protein genes and construction of phylogenetic trees for all the human paramyxoviruses.

The nucleotide sequences of the NP and M genes of human parainfluenza type 1 virus (HPIV-1) were determined. The NP gene was 1677 nucleotides long excluding polyadenylic acid. The NP gene contained a single large open reading frame (ORF), which encoded a polypeptide of 524 amino acids with a calculated molecular weight of 57,736. The M gene 1173 nucleotides long excluding the poly(A) tract and the sequence also contained a single large ORF which encoded a polypeptide of 348 amino acid with a molecular weight of 38,445, which was inconsistent with 28 kDa previously determined by SDS-PAGE. We aligned the deduced HPIV-1 NP and M protein sequences with 12 and 13 other paramyxoviruses, respectively, suggesting that a common tertiary structure was found in the NPs or Ms of HPIV-1, Sendai virus (SV), HPIV-3 and BPIV-3 and that other common structure was also maintained in these proteins of HPIV-2, SV 41 and 5, MuV, HPIV-4. Phylogenetic trees were constructed for the NP and M proteins of all the paramyxoviruses of which nucleotide sequences had been previously reported. Paramyxoviruses could be subdivided into two groups, i.e., PIV-1 group and PIV-2 group; the former group is composed of HPIV-1, SV, HPIV-3 and BPIV-3, and the latter group consists of HPIV-2, SV 41, SV 5, MuV, HPIV-4 A and HPIV-4 B.

Amino Acid Sequence↗

PubMed1992

Growth retardation due to idiopathic growth hormone deficiencies: MR findings in 24 patients.

In this study we evaluated the pituitary-hypothalamic abnormalities of "idiopathic growth hormone (GH) deficiency" as demonstrated by MR imaging. Twenty-four patients were examined with a 1.5-T unit using spin echo T-1 weighted images. The patients were divided into two groups according to MR findings: those with ectopic posterior pituitary glands (12 patients), and those with normal posterior pituitary glands (12 patients). Ten patients in the former group and four in the latter group had small anterior pituitary glands. All patients in the former group but only four in the latter group had severe GH deficiencies. Multiple hormone deficiencies were found in eight patients in the former group, but in only two in the latter group. Among the 12 patients with posterior pituitary ectopia, 11 were males, 10 had been born by breech delivery, and four had a history of asphyxia. It is speculated that perinatal abnormalities can cause posterior pituitary ectopia and that there is a close correlation between breech delivery and the male disadvantage of posterior pituitary ectopia. Half of our patients with "idiopathic GH deficiency" had ectopic posterior pituitaries. GH deficiency with posterior pituitary ectopia should no longer be considered idiopathic because organic lesions can now be identified during life.

Adolescent↗

PubMed1992

Changes in retinal projections and ganglion cell morphology after unilateral enucleation in the common carp.

Changes in retinal projections and ganglion cell morphology were studied in one-eyed individuals of the common carp, Cyprinus carpio, which were enucleated at a juvenile stage (within 6 months after hatching) and kept for 18 months after the operation. Gross examination of the brains showed a marked atrophy of the contralateral optic tectum and a fine attenuated optic tract ipsilateral to the remaining eye. All retinal recipient areas were bilateral, but numerous projections were heavier contralaterally. Terminal branches in the recipient areas showed more complex patterns with tortuous courses and larger numbers of terminal swellings than in normal animals. Total numbers and distribution patterns of ganglion cells in Nissl-stained retinal whole mounts of one-eyed carp were compared with those in normal carp. The total number of ganglion cells was estimated to be 14 x 10(4)-18 x 10(4) in both one-eyed and normal carp. No difference was observed in isodensity maps and soma area histograms between one-eyed and normal carp. Following injections of horseradish peroxidase and nuclear yellow into the optic tectum of each side, three different types of tectal projecting ganglion cells were observed in the remaining retina: contralaterally projecting (CP) cells, ipsilaterally projecting (IP) cells, and bilaterally projecting (BP) cells. The distribution pattern of CP and BP cells in the retina suggested normal retinotopy. However, BP cells were found in a more restricted zone within the CP cell distribution area. The IP cells had a tendency to be scattered sparsely in a wide central area and a dorsal quadrant of the retina. No IP or BP cells were found in the peripheral retina. The time course and morphological changes in axons of these cells are discussed.

Animals↗

PubMed1992

[The selachian terminal nerve].

In order to clarify morphology and function(s) of the terminal nerve, gross examinations of the nerve were carried out in 9 species of selachians. The terminal ganglion was observed light- and electron-microscopically. FMRF-amide immunoreactivity of the terminal nerve was also examined in some species. The results were as follows: 1) The terminal nerve was divided into peripheral and central branches by interposed ganglion(s). Macroscopically, the peripheral branch appeared from an area between the nasal sac and the olfactory bulb. The central branch entered the telencephalon from either the rostral, dorsal, or ventral surface. The position seemed to differ from species to species. 2) The terminal nerve showed great species differences and individual variations in the macroscopic morphology, such as number and course of the peripheral branch, position, size and number of ganglia, and telencephalic areas where the central branch entered. Even in the same individual, there was a difference in left and right sides. 3) According to general histology, the ganglion was encapsulated and had no direct connection with the telencephalon through the capsule, even when the ganglion was situated on the telencephalon. The Bodian preparations showed that most ganglion cells were unipolar, and a few were bipolar or pseudounipolar. 4) All ganglion cells and the processes were FMRF-amide immunoreactive. Immunoreactive fibers of the central branch terminated in the septal and preoptic areas. FMRF-amide immunoreactive cells were also found in the olfactory nerves or the septal area of the telencephalon in some species. These neurons were thought to be ectopic ganglion cells. 5) Neuronal somata and the axons in the ganglion contained large dense cored vesicles.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1992

[The spread of breast cancer and indications of breast preserving operation].

Pathological investigations for intramammary spread of breast cancer of 205 partially resected specimens were performed by making continuous section every 5 mm width of the whole specimen. The materials were 167 quadrantectomized and 38 lumpectomized specimens. The results showed that the margin of 15.6% of quadrantectomized and 28.9% of lumpectomized specimens were positive for cancer, main causes of which were intraductal spread of cancer occupying 65% of positive margin in quadrantectomy and 91% in lumpectomy, multiple cancer, interstitial spread of cancer and so on. Multiple cancers were found in eleven (6.6%) quadrantectomized and in one (2.6%) lumpectomized specimens. Second cancers were 11 noninvasive ductal and 3 invasive cancers, including two triple cancers. Fifteen cases of quadrantectomy and 4 of lumpectomy were changed to be mastectomized because of positive margin or nodal involvements. Radiotherapy was performed for 33 cases. The median 31 months follow-up results of 186 partially mastectomized breast in 184 patients were as follows; one local recurrence in lumpectomy, two new cancers in residual breast, two distant metastases and one death for other cause of death. Quadrantectomy plus axillary dissection without radiotherapy assured of pathological complete resection was safe enough at the present.

Breast Neoplasms↗

PubMed1991

[Clinical studies on 3 pairs of monozygotic twin sisters affected by Graves' disease].

Clinical studies were undertaken of three pairs of monozygotic twin sisters affected by Graves' disease. The evidence that the twins were monozygotic was established by similarity in physical appearance, identical blood-group antigens and identical HLA types. All pairs were female, and the evidence of Graves' disease in both members of the pair was observed in 2 out of 3 pairs. In the remaining pair the disease started in the elder sister, but the younger sister still remained in euthyroidism in spite of the presence of diffuse goiter. The disease occurred in the second decade in all the patients, and the interval between the occurrence of the disease in twin sisters was 1 to 4 years. No common specific type of HLA was found among all three pairs, but DR4 was common in two pairs of twin sisters showing positive MCHA test. Serum TRAb was positive in 2 pairs of twin sisters but negative in the remaining one. However, it became positive in the elder sister of the latter pair during the antithyroid treatment. The effect of antithyroid drug treatment was found to be similar in each of the twin sisters, and the serum TRAb moved almost in parallel with serum FT4 level. These results indicate that a genetic factor may be of great importance in the aetiology of Graves' disease, and there was a strong preponderance for it to occur in women and the second decade was the peak age for its occurrence. The common specific type of HLA for all Graves' patients was not found in this study. A strong relationship was observed between Grave's disease and TRAb.

Adult↗

PubMed1991

Structural and functional analysis of a polyoma-related mammalian plasmid (L factor): the enhancer activity and plasmid establishment.

L factor is a unique plasmid DNA which was originally discovered in a subclone (B822) of mouse L cells at a high copy number (more than 5,000 copies/cell). The presence of L factor caused no detectable abnormalities to the plasmid-bearing cells. We determined the total DNA sequence of the L factor I (and a part of L factor II) and compared it with that of polyoma DNA. Both DNA are common to the general construction of DNA frames such as early, late and noncoding regions, suggesting the two to be closely related. On the other hand, the L factor DNA sequences differ substantially from that of polyoma in the DNA sequences corresponding to the polyoma large T antigen, capsid proteins and a portion of the enhancer region. In order to investigate the mechanism of plasmid establishment of L factor, we compared the enhancer activity, capacity of DNA replication and efficiency of plasmid establishment of L factor with those of polyoma. The results indicate that L factor enhancer activity and DNA replication capacity were considerably lower than those of polyoma, suggesting that these altered (lowered) activities associated with L factor contribute to the plasmidal establishment and stable maintenance of L factor.

Animals↗

PubMed1991

Efficacy of disopyramide in conversion and prophylaxis of post-thyrotoxic atrial fibrillation.

Rhythm conversion in patients with post-thyrotoxic atrial fibrillation (AF) has been performed with disopyramide in order to evaluate the conversion rate and to test its effect on the maintenance of sinus rhythm after cardioversion. The duration of AF ranged from 9 to 122 months (mean 31.8 months). Of 81 patients, 12 (15%) with relatively short duration AF were converted to sinus rhythm with disopyramide. The remaining 69 patients required DC cardioversion, which restored sinus rhythm in 58 patients. The 58 DC-converted patients were divided into two groups: a disopyramide group (D group) and a non-disopyramide group (non-D group). The D group received disopyramide 300 mg per day for 3 months after DC cardioversion and the non-D group did not receive anti-arrhythmic drugs. During the early observation period, only one patient relapsed in the D group into AF, but 5 successive patients in the non-D group reverted to AF, forcing discontinuation of the non-D protocol. A second DC cardioversion performed on 3 of those 5 patients was followed by maintenance therapy with disopyramide 300 mg per day, and they remained in sinus rhythm. With the inclusion of those three subjects, sinus rhythm was still present in 44 of the total of 58 patients converted by DC (76%) at the time of follow-up (64 months). Thus, disopyramide was effective in rhythm conversion and it was essential for the maintenance of sinus rhythm after cardioversion in patients with post-thyrotoxic AF.

Adolescent↗

PubMed1991

Rapid detection of a point mutation in thyroid-stimulating hormone beta-subunit gene causing congenital isolated thyroid-stimulating hormone deficiency.

Previous study showed that congenital isolated TSH deficiency in Japan is resulted exclusively from a G-A transition at nucleotide 145 in exon 2 of the TSH beta-subunit gene. All reported cases were from the inbred in Shikoku Island. We describe here a 10-year-old boy with hereditary TSH deficiency in the same area. The patient was born with a weight of 3,225 g to non-consanguineous parents. Evaluation at age 2 months revealed typical manifestations of cretinism without goiter. Serum T4, T3, and TSH values were 2.53 micrograms/dl, 107 ng/dl, and 0.5 microU/ml, respectively. A TRH stimulation test showed no increment of serum TSH value. Other anterior pituitary hormone levels were all within the normal range. Two oligonucleotide primers T1a and T1b were synthesized according to the sequence data. Amplified 169 bp nucleotides in exon 2 of the TSH beta gene with this primer set were digested with MaeI. Both the phenotypically normal brother and normal controls showed only the 169 bp fragment, whereas the proband showed 140 and 29 bp fragments and both parents showed three fragments; 169, 140, and 29 bp. These results were consistent with the point mutation of TSH beta gene in Japanese patients with congenital isolated TSH deficiency. Our PCR method with MaeI digestion contributes to the rapid detection of the homozygous patient and the heterozygous carrier.

Child↗

PubMed1991

Correlated expression of mRNAs of carcinoembryonic antigen and nonspecific cross-reacting antigen genes in malignant and nonmalignant tissues of the colon.

Expression of carcinoembryonic antigen (CEA) and nonspecific cross-reacting antigen (NCA) mRNAs were observed in malignant and nonmalignant colon tissues by Northern blot analysis. CEA mRNA was detected together with NCA mRNA in nine cultured cell lines, with the exception of the lung carcinoma A549 cell line, and in 19 colon tissue specimens, including carcinomas, adjacent noninvaded tissues and adenomas. When we compared the intensity of the hybridization signal for CEA or NCA mRNA among adenomas, carcinomas and adjacent noninvaded tissues, NCA mRNA rather than CEA mRNA was highly expressed in carcinomas compared to adjacent nonivaded tissues. When, however, the relation between the intensities of hybridization signals for CEA and NCA mRNAs were evaluated in five colon carcinoma cell lines and 19 colon tissue specimens, a statistically significant correlation was observed (gamma = 0.462, P less than 0.01). These data suggest that NCA may be more useful as a tumor marker for colon carcinoma than CEA at the level of mRNA, and that transcriptions of the CEA and NCA genes might be regulated by some common mechanisms in malignant and nonmalignant tissues of the colon.

Adenoma↗

PubMed1991

Molecular relationships between human parainfluenza virus type 2, and simian viruses 41 and 5: determination of nucleoprotein gene sequences of simian viruses 41 and 5.

The nucleotide sequences of cDNAs of the simian virus 5 (SV5) nucleoprotein (NP) gene, and the 3' end of the genome and NP gene of SV41 were determined. The open reading frames of the SV5 and SV41 NP genes encode polypeptides with Mrs of 56,582 and 60,575, respectively, values which are consistent with those estimated by SDS-PAGE. The NP of human parainfluenza virus type 2 (hPIV-2) was more closely related to that of SV41 (amino acid sequence identity 70.5%) than that of SV5 (57.0%); the amino acid sequence identity between the NPs of SV41 and SV5 was 63.3%. The sequence of the 3' end of the genome of SV41 showed a high level of similarity to that of hPIV-2, the terminal 18 nucleotides being identical. It is concluded from these findings that SV41 is related most closely to hPIV-2, even though SV5 had been thought to be an animal type of hPIV-2.

Amino Acid Sequence↗

PubMed1991

Deletion pattern in the 21-hydroxylase gene detected by polymerase chain reaction.

In order to detect deletion mutation and/or gene conversion in the 21-hydroxylase (21-OH) gene, we adopted the polymerase chain reaction (PCR) method followed by electrophoresis. Two pairs of synthesized primers, Ta/1b and 2a/2b, each corresponding to the sequence at the 5' portion of the 21-OH gene, were set for PCR. TaqI digestion of amplified DNA from normal individuals using Ta/1b as primers gave the following three fragments: an active 21-OH gene-derived 559 bp fragment, and pseudogene-derived 364 and 195 bp fragments. Of 16 patients with 21-hydroxylase deficiency (21-OHD) studied, 6 (37%) lacked the 559 bp fragment. These 6 patients also lacked both the 331 and 117 bp MvaI fragments of the PCR product which were obtained with the primers 2a/2b, both being derived from the active 21-OH gene. These results indicate that 6 of the 16 patients have either deletion of the 21-OH gene or conversion of the gene to its tandemly located pseudogene. The method described here provides a rapid diagnosis of 21-OHD.

Adrenal Hyperplasia, Congenital↗

PubMed1991

Evaluation of lumbar bone mineral density by dual energy x-ray absorptiometry.

Using dual-energy x-ray absorptiometry (DEXA), the lumbar spinal bone mineral density (BMD) in 49 Japanese children with or without metabolic bone disease (MBD) was determined. The following results were obtained: (a) The normal data for healthy Caucasians (J Clin Endocrinol Metab 1990; 70: 1330-1333) appear to be applicable to Japanese children; (b) BMD was normal in patients with congenital hydronephrosis with normal renal function; (c) One patient with congenital renal failure and one with Lowe syndrome had low BMD, but the MBD in the former improved markedly with peritoneal dialysis; (d) A reduced BMD was found in patients treated with long-term steroids, probably because of decreased turnover of bone; (e) A reduction in BMD was pronounced in preterm infants during the first few months of life. In conclusion, DEXA is a useful method of bone densitometry in MBD in children.

Absorptiometry, Photon↗

PubMed1991

A case of neonatal McCune-Albright syndrome with Cushing syndrome and hyperthyroidism.

We describe a female newborn infant with McCune-Albright syndrome. In addition to the cutaneous pigmentation, she had apparent manifestations of hyperthyroidism and Cushing syndrome since birth. X-ray examinations showed many scattered lucencies in multiple bones. Endocrinological findings were as follows: serum T 4 276 nmol/l; free T 4 125 pmol/l; TSH less than 1 mU/l; serum cortisol greater than 2210 nmol/l; plasma ACTH less than 10 pg/ml; urinary free cortisol 865 nmol/day; estradiol 0.36 nmol/l. Regardless of treatment with antithyroid drugs and an inhibitor of 3 beta-hydroxysteroid dehydrogenase, the patient died of cardiac failure at the age of 4 months. Autopsy findings included a follicle cyst in the right ovary and multinodular hyperplasia in the thyroid and both adrenals. To our knowledge such a severe neonatal form of McCune-Albright syndrome has not been described in the literature.

Adrenal Cortex↗

PubMed1990

Cytoarchitecture and fiber connections of the nucleus lateralis valvulae in the carp (Cyprinus carpio).

The cytoarchitecture and fiber connections of the nucleus lateralis valvulae of the carp (Cyprinus carpio) were studied by Nissl, Bodian, Golgi, and horseradish peroxidase methods. Chief cells composing the nucleus lateralis valvulae (NLV) are small and granular, and their axons terminate in the cerebellum. These neurons have no dendrite, and the cell body is enveloped in a single terminal of afferent fibers to the NLV. In order to observed local cell clustering, the NLV was three-dimensionally reconstructed with the aid of a computer image analysis system. Afferent sources to the NLV were the nucleus pretectalis superficialis pars magnocellularis (Northcutt and Braford, '84: Brain Res. 296:181-184), nucleus ventromedialis thalami (Ito et al., '86: J. Comp. Neurol 250:215-227), and the inferior lobe. The NLV projects to the inferior lobe and the cerebellum. In particular, the cerebellar projections were strong and topographically arranged. Some larger neurons lying just beneath the NLV, some of which were intermingled with the NLV neurons, projected to the torus longitudinalis. On the basis of the local cell clustering as well as NLV-cerebellar connections, three subdivisions of the NLV could be recognized, i.e., anterior, central, and posterior portions. The posterior portion was further subdivided into lateral and medial parts.

Animals↗

PubMed1990

Evaluation of variability of proteinuria indices.

We compared several indices of proteinuria, namely protein concentration, hourly protein excretion rate (Up/h) and protein/creatinine ratio (Up/Ucr) in single voided urine samples as well as 24 h-urinary protein excretion (24 h-Up), in 44 children, aged 4-16 years, with varying degrees of urinary protein excretion. We found an excellent correlation between Up/h and Up/Ucr in early morning samples. These two indices in early morning samples had excellent correlation with 24 h-Up, comparable to those in any other urine sample of the day. Among daytime samples, Up/h varied widely, in contrast to Up/Ucr, which had significantly less variability. We analysed six early morning and six bedtime samples from 39 of these subjects, and found smaller coefficients of variation for individual patient's indices in morning samples. Up/h was more variable than Up/Ucr, especially in bedtime samples. Urinary protein concentration had a poorer correlation with 24 h-Up and was more variable than any other index. We conclude that the Up/Ucr in early morning samples, which has the advantages both of simplicity and low day-to-day variability in a given patient, is a superior index of proteinuria.

Adolescent↗

PubMed1990

Assessment of tubular function in neonates using urinary beta 2-microglobulin.

Renal proximal tubular function was assessed in neonates by measuring urinary beta 2-microglobulin (beta 2M) concentrations on days 1, 4, 7, 14 and 28. Values were elevated in stable preterm low-birthweight (LBW) neonates but not in stable term LBW neonates, suggesting that proximal tubular maturation is related to gestational age rather than birthweight. The urinary beta 2M was significantly increased on day 1 in neonates with the meconium aspiration syndrome but was not significantly different from normal subsequently. This indicated that although the proximal tubular cells may be susceptible to perinatal hypoxia, they maintain a remarkable capacity to recover in a relatively short period. Neonates with transient tachypnoea of the newborn had normal urinary levels of beta 2M indicating their renal tubular function was not impaired.

Apgar Score↗