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Biomedical subjects

Y Manabe

Publications and source records attributed to Y Manabe.

At least 109 records · Page 6Linked to original sources
PubMed1994

Distention of the uterus activates its multiple pacemakers and induces their coordination.

In the pregnant human uterus, pacemaker activities and their coordination processes were studied in labor induced by uterine distention. Electrical and mechanical activities of the uterus were simultaneously recorded in 6 midtrimester (normal, n = 4; fetal death, n = 2) and 8 term (normal, n = 7; fetal death, n = 1) patients. Initially, frequent and sporadical spike discharges which did not synchronize with low magnitude and irregular mechanical activities were noted. With time, synchronization of both activities developed. These findings were noted regardless of the gestational stage of the patient and fetal viability. The patterns of development and decreases in mechanical and electrical activities, together with their synchronization patterns, were positively and negatively controlled by uterine distention and its suspension, respectively. These results suggest that the uterus has multiple pacemakers in various locations, and uterine distention works as a trigger for the elevation of excitability and for coordinated and orthodromic activities.

Adult↗
PubMed1994

[Chlordane accumulations in adipose tissue of mice chronically exposed to chlordanes in indoor air].

Chlordane concentrations were analyzed in the adipose tissue of mice after prolonged inhalation of low levels of chlordanes in indoor air. After inhalation of 4.22-11.36 micrograms/m3 chlordanes (total of 5 compounds) in air for 1-6 months, high levels of chlordanes (4.19-11.63 ppm, total of 5 compounds and 2 metabolites) were found in the adipose tissue. Transnanochlor, which accounted for only 14% of the total chlordane in the inhaled air, showed a high percentage (50%) in the adipose tissue, followed by 2 metabolites, i.e., oxychlordane (25%) and heptachlorepoxide (22%). Little transchlordane, cis-chlordane, or heptachlor, which accounted for high percentages of the total chlordane inhaled, was detected in the adipose tissue. A low level of cis-nonachlor was observed in the adipose tissue, and its percentage was similar to that in the air (2%). The level of chlordane exposure and the adipose tissue chlordane concentration was closely correlated (r = 0.9077, p < 0.01), showed a dose-effect relationship. These findings suggest that chlordanes such as trans-nonachlor, oxychlordane, and heptachlorepoxide may accumulate in the adipose tissue of people living in an environment containing even low levels of chlordanes and that there is a risk from indoor air contamination by chlordanes.

Adipose Tissue↗
PubMed1993

[Measurement of ethylene oxide at a medical sterilization site].

Although ethylene oxide gas is widely used as a sterilizing agent for medical instruments because of its disinfection property, the effects of its use in medical settings have not been clarified. In the present study, we measured the ethylene oxide gas concentration (EOGC) within a hospital sterilization unit and in the ambient air near the unit. Before the sterilizer was turned on (about 9:00), the ambient air EOGC was below the detection limit (0.1 ppm). When the door was opened to place the instruments in the sterilizer, the maximum EOGC near the door of the sterilizer was 1.71 ppm. Before the sterilizer door was opened, the residual EOGC within the sterilizer was 0.10-24.56 ppm. During the operation of the sterilizer (9:00-17:00), ethylene oxide gas could not be detected in the air near the unit. When the sterilizer door was opened at the end of the routine operation of the sterilizer (about 17:00), EOGC near the door was 2.10-2.73 ppm. After the door was closed, the ambient air EOGC level was 0.5-0.57 ppm. These findings indicate that the personnel near the unit were exposed to ethylene oxide gas for about 15 min during the transfer. However, no ethylene gas could be detected by the ethylene oxide gas monitor (3M Co., #3551). The finding that EOGC in sterilized medical instruments after 24 h of aeration was about 2 ppm also suggests that the personnel using these instruments were exposed to ethylene oxide gas.(ABSTRACT TRUNCATED AT 250 WORDS)

Air↗
PubMed1992

Immunohistochemical and ultrastructural studies of intraluminal crystalloids in human prostatic carcinomas.

Intraluminal crystalloids (ICr) observed in 19 cases of incidental or invasive human prostatic carcinoma (PCa) and in a case of benign prostatic hyperplasia were examined extensively by immunohistochemistry and electron microscopy. They were brilliantly eosinophilic with haematoxylin and eosin, manifesting needle-like, triangular, rectangular, hexagonal and irregular lump-like in shape. They were strongly positive, dark blue, with phosphotungstic acid -haematoxylin (PTAH) stain in all cases examined. Among the human antibodies tested, epithelial membrane antigen (EMA) gave specifically positive immunostainability with ICr in all cases. Annual ring-like lamellar or concentric structures were detected by electron microscopy. Positive staining of ICr with PTAH and anti-EMA antibody is very useful as a diagnostic marker for PCa in human prostatic tissues.

Aged↗
PubMed1992

Fetal viability does not affect the onset of stretch-induced labor and the increase in amniotic fluid prostaglandin F2 alpha and plasma prostaglandin F2 alpha metabolite levels.

The role of the fetus in the onset and progress of stretch-induced labor and in the change in amniotic fluid prostaglandin F2 alpha and plasma prostaglandin F2 alpha metabolite levels was evaluated in six normal pregnant women (group 1) and six women whose fetuses had been dead for more than one week (group 2). The uterus was distended by a balloon inflated with physiologic saline. Regular uterine contractions occurred, and increased in all patients. Within 21 hours, all patients delivered a normal baby in group 1 and a macerated fetus in group 2. There was no significant difference in induction-delivery interval between the two groups. Both groups showed a significant and similar range of increases in the levels of amniotic fluid prostaglandin F2 alpha and plasma prostaglandin F2 alpha metabolite during treatment (P less than 0.001). Thus, the fetus has no functional role in the onset and progress of stretch-induced labor or in the rise of amniotic fluid prostaglandin F2 alpha and plasma prostaglandin F2 alpha metabolite levels.

Adult↗
PubMed1992

Localization of GABAA-receptor gamma 2-subunit mRNA-containing neurons in the rat central nervous system.

The localization of neurons containing mRNA of the gamma 2-subunit of GABAA receptors was examined in the rat central nervous system with in situ hybridization histochemistry using an oligonucleotide probe to the sequence of the gamma 2-subunit. Neurons containing the gamma 2-subunit mRNA were widely but unevenly distributed in the brain. The location of gamma 2-subunit mRNA-containing neurons differed from those containing alpha- or beta-subunits. According to our results brain regions can be divided into three categories: one containing only gamma 2-subunit, one containing mRNA of at least one subunit other than gamma 2 and one containing more than one other subunit but not the gamma 2-subunit. The distribution of strongly labeled nuclei partly coincided with that of glutamate decarboxylase, suggesting that the GABAA receptor gamma 2-subunit would be involved in an autoreceptive mechanism of the GABAergic transmission.

Animals↗
PubMed1992

Establishment and characterization of a new human synovial sarcoma cell line, HS-SY-II.

BACKGROUND: The line of differentiation in synovial sarcoma still remains controversial. Thus far, only a few human synovial sarcoma cell lines have been described. However, their morphologic characteristics have not been fully established. EXPERIMENTAL DESIGN: We established a new synovial sarcoma cell line (HS-SY-II) from pleural effusion with lung metastasis in a typical example of the monophasic spindle cell type. The HS-SY-II cells, in vitro and in vivo, were examined by light microscopy, immunohistochemistry, electron microscopy, and cytogenetics. RESULTS: The HS-SY-II cells showed a hypertriploid karyotype with complex chromosome abnormalities including pathognomonic t(X;18)(p11;q11), and have been stably maintained for more than 40 months in vitro, showing rather small spindle or polygonal shape without conspicuous pleomorphism. Histologic features of initially and serially transplanted tumors in nude mice were essentially the same as those of the original sarcoma, corresponding to the monophasic spindle cell variant with a prominent palisading pattern and calcified foci in parts. The HS-SY-II cells in vitro and in vivo similarly expressed vimentin and cytokeratin by immunohistochemistry, and also exhibit the same ultrastructural features such as irregularly shaped nuclei with prominent nucleoli, many paranuclearly running intermediate filaments, and filopodia-like processes. CONCLUSIONS: This HS-SY-II cell line retaining the distinct morphological characteristics as the monophasic spindle cell type of synovial sarcoma therefore will be extremely useful for various pathomorphologic investigations on synovial sarcoma.

Cytological Techniques↗
PubMed1992

Nonmetric tooth crown traits in the Ami tribe, Taiwan aborigines: comparisons with other east Asian populations.

The frequencies of occurrence of 17 tooth crown traits in the living Ami tribe, which inhabits the east coast of Taiwan, were investigated and compared with other East Asian populations based on Turner's (1987) Mongoloid dental variation theory. Principal coordinate analysis based on Smith's mean measure of divergence using frequencies of the 17 traits suggests that the Ami tribe together with the Yami tribe and the Bunun tribe is included in the sinodont group typical of the Chinese mainland and northeast Asia. In light of these results and the estimated distribution of sinodonty and sundadonty in the past and the present, we speculate that the gene flow from Chinese mainlanders to native sundadonts, who seem to have migrated northward to Taiwan, contributed significantly to the formation of the living Taiwan aboriginal groups, sinodonts. Among the aboriginal tribes of Taiwan, the Ami have characteristics intermediate between those of the Yami and the Bunun. The relative positions of these tribes in East Asian populations suggests that the extent of sinodontification and of genetic isolation is one of the causes of the intertribal variation.

Adolescent↗
PubMed1992

[Comparison of wound healing of linear incisions in the rabbit cornea produced by the newly developed excimer laser, a metal blade, and a diamond blade].

We developed a new delivery system for corneal ablation with the 193 nm argon-fluoride excimer laser. The laser was used to make linear incisions in the rabbit cornea, and wound healing of the incisions was compared with the healing of incisions made with metal and diamond blades. The morphology of incisions made with excimer laser radiation (193 nm) was compared with the morphology of incisions produced by diamond and metal blades, and the corneal wound was examined by light and electron microscopy. The surface of the cornea at the site of the laser wound was smooth; the laser wound was wider than the blade wounds immediately after surgery. Two weeks after surgery, all wounds had healed equally. One month after surgery, there were fewer fibroblastic keratocytes in the laser wound, and the epithelial layer at the wound site was thinner than in the case of the blade wounds. These results suggest that wound healing of laser incisions is more rapid than healing of wounds created with metal or diamond blades.

Animals↗
PubMed1991

Morphological characterization of a newly established human osteosarcoma cell line, HS-Os-1, revealing its distinct osteoblastic nature.

A newly established human osteosarcoma cell line, HS-Os-1, from an osteoblastic tumor arising in the left humerus of an 11-year-old girl was morphologically characterized in vitro and in vivo. HS-Os-1 cells in a monolayer have been maintained for more than 2 years since the initial cultivation, and were round or polygonal in shape with marked pleomorphism. Their cytoplasm was strongly positive for specific markers of osteoblasts, such as alkaline phosphatase and osteocalcin. Tumors induced in nude mice by HS-Os-1 cell inoculation at passage 12 or 23 revealed typical histological features of osteoblastic osteosarcoma, similar to those observed in the original tumor, producing prominent osteoid matrix with calcification. Ultrastructurally, HS-Os-1 cells in vitro and tumor cells in vivo showed similar well-developed, markedly dilated rough endoplasmic reticulum, polysomes and microfilaments in their cytoplasm. Additionally, many collagen fibers associated with deposition of electron-dense material were detected in the stroma featuring osteoid matrix. Thus, the HS-Os-1 cell line was shown to exhibit its osteoblastic nature in vitro and in vivo, and therefore might become an extremely useful tool for various pathomorphological investigations on human osteosarcomas.

Animals↗
PubMed1991

Recurrent perforations of viscus due to ventriculoperitoneal shunt in a hydrocephalic child.

In this report, we describe the first case of recurrent perforations of viscus due to ventriculoperitoneal shunt for the treatment of hydrocephalus. Based on our own experience and a survey of literature, we suggest that perforation of the gastrointestinal tract should be suspected in patients with ventriculoperitoneal shunt, particularly when abdominal symptoms or ventriculitis are presented. To manage this complication, at the first perforation in the present case, a fibrin sealant was effective for closure of the perforated stomach wall. At the second perforation, when laparotomy was performed, we could not find any abnormality in the abdominal cavity except for a sheath and slight omental adhesions near it.

Cerebrospinal Fluid Shunts↗
PubMed1991

Intravenous gamma-globulin for Kawasaki disease.

We studied the effect of gamma-globulin (IVGG) and aspirin (ASA) on the development of the coronary artery lesions (CAL) of Kawasaki disease (KD) in three different protocols. Within 29 days of the onset of KD the echocardiographic evidence of CAL had developed in 39-42% of the patients in the ASA group, but only in 13.7-20.8% of the patients treated with IVGG (200 or 400 mg/kg X 5). In long-term follow-up observation of CAL of these patients the evidence of CAL in both the ASA and the IVGG group regressed gradually; however, the residual rate of CAL was significantly low in the IVGG group at all times up to 24 months after onset. These facts suggest that when using IVGG for KD, we should select a dose of intact gamma-globulin, 1,000 mg/kg or more in total, to prevent the occurrence of CAL. We have demonstrated not only a significant reduction in the occurrence of CAL in patients treated with IVGG but a reduction in the residual rate of CAL for two years as compared with those treated by ASA.

Aspirin↗
PubMed1991

Structure, chromosome location, and expression of the human smooth muscle (enteric type) gamma-actin gene: evolution of six human actin genes.

Recombinant phages that carry the human smooth muscle (enteric type) gamma-actin gene were isolated from human genomic DNA libraries. The amino acid sequence deduced from the nucleotide sequence matches those of cDNAs but differs from the protein sequence previously reported at one amino acid position, codon 359. The gene containing one 5' untranslated exon and eight coding exons extends for 27 kb on human chromosome 2. The intron between codons 84 and 85 (site 3) is unique to the two smooth muscle actin genes. In the 5' flanking region, there are several CArG boxes and E boxes, which are regulatory elements in some muscle-specific genes. Hybridization with the 3' untranslated region, which is specific for the human smooth muscle gamma-actin gene, suggests the single gene in the human genome and specific expressions in enteric and aortic tissues. From characterized molecular structures of the six human actin isoform genes, we propose a hypothesis of evolutionary pathway of the actin gene family. A presumed ancestral actin gene had introns at least sites 1, 2, and 4 through 8. Cytoplasmic actin genes may have directly evolved from it through loss of introns at sites 5 and 6. However, through duplication of the ancestral actin gene with substitutions of many amino acids, a prototype of muscle actin genes had been created. Subsequently, striated muscle actin and smooth muscle actin genes may have evolved from this prototype by loss of an intron at site 4 and acquisition of a new intron at site 3, respectively.

Actins↗
PubMed1991

[Assessment of cadmium and lead released from cigarette smoke].

Cigarette smoke, which contains many harmful compounds, affects not only the smoker's health but also indoor air quality. To evaluate indoor air contamination by cadmium (Cd) and lead (Pb), we measured Cd and Pb contained in the mainstream and sidestream smoke exhaled by experimental smoking of Japanese cigarettes and also determined urinary and blood Cd and Pb levels in smokers and non-smokers and air Cd and Pb levels in smoky environments. 1. One cigarette of each of 7 Japanese brands contained about 1 microgram each of Cd and Pb, of which about 50 ng each was released to the mainstream and 250 ng of Cd and 50 ng of Pb to the sidestream by smoking. 2. The blood Cd level in the smokers was significantly higher than that in the non-smokers. The urinary Cd level in the smokers was slightly higher than that in the non-smokers. The blood Cd level was related to the number of cigarettes smoked daily. Blood and urinary Pb levels did not differ between the smokers and non-smokers, but the blood Pb level was also related to the number of cigarettes smoked daily. 3. The air Cd levels in smoky places such as the smoking car of the special express train, an office, and a pachinko parlor were markedly higher than that in outdoor air. The air Cd concentration was well correlated with the environmental tobacco smoke concentration. On the other hand, the air Pb level was slightly higher in the above smoky places than outdoors. The mean air Pb concentration was not correlated with the environmental tobacco smoke concentration but was higher at higher environmental tobacco smoke concentration in each place.

Adolescent↗