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Biomedical subjects

A Nakanishi

Publications and source records attributed to A Nakanishi.

At least 19 recordsLinked to original sources
PubMed1992

Phosphorylation and activation of tyrosine hydroxylase in PC18 cells: a cell line derived from rat pheochromocytoma PC12 cells.

Treatment of rat pheochromocytoma PC18 cells (a variant subclone of PC12 cells) with forskolin produced increased activity and phosphorylation of tyrosine hydroxylase. In contrast, treatment of the PC18 cells with 56 mM K+, A23187, phorbol-12-myristate-13-acetate (PMA) or phorbol-12,13-dibutyrate (PDB) did not affect the activity and only slightly increased the phosphorylation of tyrosine hydroxylase. None of the treatments except forskolin increased cyclic AMP levels in PC18 cells. Furthermore, 45Ca2+ uptake into PC18 cells was not affected by 56 mM K+, PDB or forskolin; however, A23187 increased 45Ca2+ uptake 4-fold over basal uptake. Nevertheless, no activation and little increase in phosphorylation of tyrosine hydroxylase was observed in PC18 cells treated with A23187. When tyrosine hydroxylase levels in PC18 cells were elevated by treatment with dexamethasone, activation of tyrosine hydroxylase by 56 mM K+, PDB or A23187 was still not observed. Both purified Ca2+/calmodulin-dependent protein kinase and cyclic AMP-dependent protein kinase catalyzed the phosphorylation of tyrosine hydroxylase purified from PC18 cells in vitro. Furthermore, crude cell extracts from PC12 cells and PC18 cells possessed Ca2+/calmodulin-dependent protein kinase activity that catalyzed the phosphorylation of purified tyrosine hydroxylase. These results suggest that tyrosine hydroxylase activity in PC18 cells is regulated by a cyclic AMP-dependent mechanism. However, due to a number of abnormalities the Ca(2+)-dependent mechanisms do not result in the activation of tyrosine hydroxylase and only slightly increase the phosphorylation of the enzyme in PC18 cells.

Animals↗
PubMed1992

Direct evidence for interaction between COOH-terminal regions of cytochrome b558 subunits and cytosolic 47-kDa protein during activation of an O(2-)-generating system in neutrophils.

Cytochrome b558 in phagocytes is a transmembrane protein composed of large and small subunits and considered to play a key role in O2- generation during the respiratory burst. The COOH-terminal regions of the cytochrome subunits protrude to the cytoplasmic side and are assumed to be the sites for association with cytosolic components to form an active O(2-)-generating complex (Imajoh-Ohmi, S., Tokita, K., Ochiai, H., Nakamura, M., and Kanegasaki, S. (1992) J. Biol. Chem. 267, 180-184). We show here that two synthetic peptides corresponding to the COOH-terminal region of each subunit inhibit NADPH-dependent oxygen uptake induced by sodium dodecyl sulfate (SDS) in a cell-free system consisting of plasma membrane and cytosol. The inhibition was observed when either peptide was added to the system before, but not after, the activation with SDS suggesting that interaction between the COOH-terminal regions of the cytochrome subunits and cytosolic components is important for the assembly and the activity of the O(2-)-generating system. Using the cross-linking reagent dimethyl 3,3'-dithiobis-propionimidate, we found that the cytosolic 47-kDa protein, an essential component of the O(2-)-generating system, interacted with the synthetic peptides in the presence of SDS. In addition to the 47-kDa protein, a 17-kDa protein was found to be associated with the peptide corresponding to the COOH-terminal region of the small subunit. These results indicate that the cytosolic COOH-terminal regions of cytochrome b558 subunits are the binding sites for both the cytosolic 47-kDa protein and the 17-kDa protein and that the binding takes place during activation of the system.

Amino Acid Sequence↗
PubMed1992

[Adverse reactions to low osmolar iodine contrast media (second report)].

From January to December 1990, we performed a prospective survey of adverse reactions to contrast media at two different institutes of Juntendo University. We collected a total of 4555 case sheets during the period. The radiological procedures we investigated were computed tomography, intravenous urography, arteriography, venography and myelography. Low osmolar iodine contrast medium was used almost exclusively (except for five cases). The overall incidence of adverse reactions was 7.0%, and there were no severe or fatal reactions. The incidence of adverse reactions was higher in females (8.5%) than in males (6.1%). The incidence of adverse reactions increased according to the dose of contrast medium, especially when more than 101 ml was injected. Intra-arterial injection caused adverse reactions most often, followed by regular intravenous injections, followed by bolus intravenous injections. Adverse reactions occurred most often during injection. The next occurred in 5 minutes after injection, and then, 5-10 minutes after the injection of contrast medium. The incidence of adverse reactions was higher in patients with a history of allergy or previous reactions. Allergic adverse reactions were observed at a higher frequency. Pretesting was performed in 56.7% of the cases.

Adolescent↗
PubMed1992

Clinical assessment of carcinoma in situ of the human urinary bladder.

Recent interest in intravesical instillation of bacillus Calmette-Guérin for the management of carcinoma in situ (CIS) of the bladder prompted us to review our results of total immediate cystourethrectomy. From 1975 to 1987, we surgically treated 302 patients with primary bladder tumours. Of these, 21 bladder tumours were histologically diagnosed as CIS, and total immediate cystourethrectomy was performed in all cases. The lesions were classified into three types: primary CIS accompanied by neither previous nor simultaneous tumours of the urinary tract (Type 1, 9 patients), concomitant CIS associated with superficial papillary tumour (Type 2, 6 patients), and secondary CIS detected during the follow-up period after treatment of the superficial papillary tumour (Type 3, 6 patients). Primary CIS was more often diagnosed according to subjective symptoms such as micturition pain than concomitant CIS. Secondary CIS was diagnosed in all patients by routine examinations including cytology and cystoscopy. There was no particular relationship between the time of recurrence of the tumour and the occurrence of secondary CIS. Within the same period, 60 patients with stage T1 bladder tumour were treated by total cystourethrectomy. The actuarial 5-year survival rate was 77% for T1 and 75% for CIS. The 5-year survival rate was 71% for Type 1, 83% for Type 2, and 67% for Type 3 CIS with no difference among the CIS types. Tumour invasion to the bladder, prostate, ureter, or lymph nodes was observed in 9 (42.9%) of the 21 patients, although cystourethrectomy was performed within 3 months of the diagnosis. Examination of ABH antigens did not allow prediction of invasion of CIS. Our findings suggest that the invasive potential of CIS may seriously limit the indications of conservative treatment against carcinoma in situ.

Adult↗
PubMed1992

[Laryngeal fractures due presumably to tracheal intubation in resuscitation].

In three autopsy cases performed in our department, we observed the throat-skeleton fractures occurring presumably during the tracheal intubation in resuscitation. Case 1. 63-year-old man died of acute hemorrhagic pancreatitis shortly after the quarrel with a suspected person. The autopsy examination showed the fractured hyoid bone with haemorrhage at the fracture site. The question whether direct pressure on his neck by the suspected person results the fracture of the hyoid bone was investigated. Case 2. 75-year-old man treated for senile dementia was clubbed with a walking stick by the other patient treated for same disease and he died of traumatic shock. The fracture of the hyoid bone was also noted like case 1. The strike in the throat and/or the neck compression by the assailant were suspected of being the cause of this fracture. Case 3. 47-year-old man got the severe head injury during the quarrel. He died about two weeks after operation and the cause of death was multiple organ failure. The autopsy findings revealed the fracture of the superior thyroid horn. The neck compression by the suspected person was the questionable cause of this fracture. In all these cases, the asphyxia findings and the signs of the direct pressure on the neck by the assailants were not recognized other than the above-mentioned laryngeal fractures. From the autopsy findings, together with the criminal investigation, we consider collectively that the tracheal intubation in resuscitation induced presumably these laryngeal injuries. In general, throat-skeleton fractures seem to be the signs of homicidal violence against the neck.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1991

Characterization of palytoxin-induced catecholamine secretion from cultured bovine adrenal chromaffin cells. Effects of Na(+)- and Ca(2+)-channel blockers.

The effect of palytoxin (PTX), a potent marine toxin, on catecholamine (CA) secretion from cultured bovine adrenal chromaffin cells was examined. PTX at concentrations of over 10(-10) M induced CA secretion concentration-dependently. About 40-50% of the total cellular CA was secreted during 20-min incubation with 3 x 10(-8) M PTX. PTX-induced CA secretion was dependent on both extracellular Na+ and Ca2+. PTX caused increases in [22Na](+)- and [45Ca](2+)-influxes into the cells. Increase in [22Na](+)-influx was observed at concentrations of over 10(-11) M PTX and was maximal at 10(-10) M PTX and then gradually decreased at higher concentrations that induced [45Ca](2+)-influx and CA secretion. On the other hand, increase in [45Ca](2+)-influx was observed at concentrations of over 10(-10) M PTX and increased with increase in concentration of PTX. This concentration-response curve for PTX-induced [45Ca](2+)-influx was similar to that for PTX-induced CA secretion. The CA secretion and [22Na](+)- and [45Ca](2+)-influxes induced by PTX were not affected by tetrodotoxin (TTX), but were significantly inhibited by quinidine and aprindine(mexiletine), antiarrythmic drugs known to block Na(+)-channels. Ca(2+)-channel blockers such as nifedipine, verapamil, Co2+, Cd2+, inhibited both CA secretion and [45Ca](2+)-influx induced by PTX. These results indicate that PTX-induced CA secretion is mediated by activation of Na(+)-dependent, TTX-insensitive voltage-dependent Ca(2+)-channels, and is inhibited by quinidine and aprindine through their inhibitory effects on the Na(+)- and Ca(2+)-influxes into the cells induced by PTX.

Acrylamides↗
PubMed1991

Palytoxin: a potent stimulator of catecholamine release from cultured bovine adrenal chromaffin cells.

The effect of palytoxin (PTX), a potent marine toxin, on catecholamine release from cultured bovine adrenal chromaffin cells was examined. PTX at concentrations of over 10(-9) M induced catecholamine release dose-dependently. About 40-50% of the total cellular catecholamine was released during 20-min incubation with 3 x 10(-8) M PTX. PTX-induced catecholamine release was dependent on both extracellular Na+ and Ca2+, and was inhibited by organic and inorganic Ca2+ channel blockers, but not by tetrodotoxin. PTX-induced increase in 45Ca2+ influx into the cells, which was associated with catecholamine release, was also inhibited by these Ca2+ channel blockers. These results indicated that PTX-induced catecholamine release was mediated by activation of Na(+)-dependent, tetrodotoxin (TTX) insensitive voltage-dependent Ca2+ channels.

Acrylamides↗
PubMed1991

Fertilizing competency of multiple ovulated eggs in the domestic fowl (Gallus domesticus).

Fertilizing competency of multiple ovulated eggs in the domestic fowl was examined by fertilization in vitro and early development in culture. Normal laying hens (White Leghorn) were treated with 75 IU of PMSG for 7 days followed by injection of anterior pituitary extracts from chickens (CAPE). Ovulation began to occur 7.5 h after injection of CAPE. These hens ovulated 1-7 ova but some premature ovulation of GV stage ova were observed. In vitro fertilization of the multiple ovulated ova was examined by inseminating 10(6)-10(7) sperm onto the germinal disks in m-Ringer's solution. The gamete or zygote nuclei were detected by DNA specific fluorescence using DAPI (4',6'-diamidino-2-phenylindole) in the histological section prepared from the germinal disk. Process of fertilization was examined in the eggs incubated for 4 h after insemination in DMEM + liquid albumen at 41 degrees C under the atmosphere of 5% CO2 in air. Fertilization rate of the total multiple ovulated eggs was 55% (11/20), in which 90% (9/10) and 10% (1/10) in the eggs recovered 7.5-8.5 h and 9.0-9.5 h after CAPE injection were obtained, respectively. Normal pronuclei were formed in five eggs of those recovered 7.5-8.5 h after CAPE injection. Early development after fertilization in vitro was also examined by incubation for 12 h in DMEM + liquid albumen at 41 degrees C under the atmosphere of 5% CO2 in air. Although development in vitro was delayed compared to that in utero condition, normal development was observed in naturally and multiple ovulated eggs.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1991

Growth fraction of human bladder tumors.

The growth fraction of bladder tumors was immunohistochemically assessed in situ using anti-DNA polymerase (Pol alpha) monoclonal antibody. This enzyme is known to be present in the nucleus of the cells in G1, S, and G2 phases. The percentage of labeled cells was expressed as the labeling index (LI). The average LI was 6.0% in normal epithelium and 17.8% in bladder tumors, this difference being significant. The labeled cells were distributed throughout both the basal and surface layers of bladder tumors. However, in some bladder tumors, the distribution of Pol alpha-labeled cells varied from area to area. The higher fraction of labeled cells was found in high grade or invasive tumors. Papillary and nodular bladder tumors showed a greater rate of cell proliferation than papillary tumors. These findings suggest that Pol alpha immunostaining could be a potent tool for easy and quick evaluation of proliferating cells in bladder tumors, thereby providing a supplement to conventional histological findings.

Aged↗
PubMed1991

Enhancing effect of partial cystectomy on rat urinary bladder carcinogenesis.

The effects of 5% and 50% partial cystectomies on bladder tumorigenesis initiated with N-butyl-N-(4-hydroxybutyl)nitrosamine(BBN) were investigated in Wistar rats by examining the histological findings and cell proliferative activity. The incorporation of bromodeoxyuridine (BrdUrd) into the DNA synthesis phase was determined by an in-vitro labeling technique. After eight weeks of treatment with drinking water containing 0.05% BBN, 5% or 50% partial cystectomy was performed at the end of week 16, and the resected bladder was sutured with dexon or silk. There was no difference in the incidence of papillary or nodular (PN) hyperplasia between the control and partial cystectomy groups. However, the incidence of cancer in the group given partial cystectomy was much higher than that in the control. All the cancers in the control group were grade-1 superficial tumors, whereas grade-2 or invasive tumor was observed in six of 40 animals in the partial cystectomy group. The 31.0% labeling index of cancer in the partial cystectomy group was greater than the 24.1% in the control group. There was also a significant difference in the number of BrdUrd-labeled cells in PN hyperplasia between the control and partial cystectomy groups. These findings indicate that partial cystectomy enhances BBN-initiated bladder carcinogenesis and the increase in DNA synthesis found in PN hyperplasia and cancer may be associated with the induction of bladder tumors.

Animals↗
PubMed1991

Cell proliferation of human bladder tumors determined by BrdUrd and Ki-67 immunostaining.

The cell proliferation of bladder tumors was assessed in situ using BrdUrd (bromodeoxyuridine) and Ki-67 immunostaining. BrdUrd is incorporated into S-phase cells, and Ki-67 monoclonal antibody recognizes a nuclear antigen present in proliferating, but not resting cells. The percentage of labeled cells was expressed as the labeling index (LI). The average BrdUrd LI obtained applying this method to normal epithelium and to transitional cell carcinoma were 4.1% and 13.1%, respectively, while the Ki-67 LI had average values of 6.2% and 17.8%, respectively. Labeled cells were distributed throughout both the basal and surface layers of transitional cell carcinoma. In general, the value of the BrdUrd LI was correlated to that of the Ki-67 LI. A relatively large fraction of labeled cells was found in high grade or invasive tumors. Bladder tumors with lymph node involvement had higher LI than those without. In addition, a high frequency of S-phase cells within tumor tissue appeared to indicate a great potential for malignancy and thus a poor prognosis. These findings indicate that immunostaining with BrdUrd and Ki-67 may be useful tools for easy and quick evaluation of proliferating cells in bladder tumors.

Adult↗
PubMed1991

The behavior of human ameloblastoma tissue in collagen matrix in vitro: an immunohistochemical study.

We investigated the three-dimensional outgrowth of human ameloblastoma cells cultured in collagen matrix. Growth patterns of four cases of ameloblastoma resembled each other and was characterized by appeared duct-like structures. Case 1 ameloblastoma was subcultured 3 times. Ameloblastoma tissues and cultured cells were stained with various lectins by avidin-biotin peroxidase complex (ABC) staining methods. Both the tissues and cultured cells had the same receptors to Concanavalin ensiforme (Con A), Ricinus communis Agglutinin (RCA-I) and Triticum vulgaris (WGA) but not to Dolichos biflorus (DBA), Ulex europaeus (UEA-1), Soybean (SBA) and Arachis hypogea (PNA). These findings indicated that the cultured cells examined in this study were ameloblastoma cells in origin.

Adolescent↗
PubMed1990

Early nuclear events of in vitro fertilization in the domestic fowl (Gallus domesticus).

In vitro fertilization in the domestic fowl (Gallus domesticus) was investigated by observation of the early nuclear events. Ova retrieved from the fimbria following ovulation were inseminated in vitro with 10(6)-10(7) spermatozoa in Dulbecco's modified Eagle's medium (DMEM) for 10 min and then further incubated in DMEM + albumen for 1, 2, 3, or 4 hr. These eggs were histologically examined by epifluorescent microscopy after staining with 4',6'-diamidino-2-phenylindole (DAPI). Nuclei of spermatozoa at various stages of transformation were observed in the ova incubated for 1-3 hr. Close pairing of two pronuclei, presumed to be male and female juxtaposition, was detected in ova incubated for 4 hr. These data provide direct evidence for the in vitro fertilization of fowl eggs and suggested that the early process of in vitro fertilization is comparable to that of in vivo fertilization.

Animals↗
PubMed1990

[A clinical evaluation of lymphography in bladder tumor].

A study was conducted in a total of 51 patients with urinary bladder tumor who had received surgical operation associated with removal of regional lymph nodes after lymphography. Abnormal findings were observed in lymphogram of 22 patients. The other 29 patients showed no such abnormality. After the operation pathological metastasis was confirmed in 7 patients. Lymphograms of these patients ith positive lymphatic metastasis revealed filling defects in 85.7% and collaterals in 57.4%. There as correlation between the occurrences of these two findings based on quantification analysis III of multivariate analysis. Lymphography before operation showed 87.5% of sensitivity, 65.1% of specificity and accuracy of 68.6%, not having higher accuracy compared to other studies. These results suggest that lymphography, which may have clinical significance, is not a decisive method in exploration of bladder tumor. Comprehensive analysis of diagnostic imaging should be performed, including CT after lymphography.

Female↗
PubMed1990

[Follow-up study of residual and recurrent stone after extracorporeal shock wave lithotripsy].

The rate of residual stones and that of recurrent lithiasis were investigated in 183 patients who had undergone extracorporeal shock wave lithotripsy (ESWL) between July, 1986 and December, 1988. The investigation was done by questionnaire survey at 22 institutions including our hospital on patients who were followed up after ESWL. The 183 patients included 126 male and 57 female patients between 9 and 77 years old (the mean 43.6 years). The greater part of patients had lithiasis of the lower renal calyx and upper ureter. The rate of residual stones 3 months after ESWL was 33.3% (61 patients) and the success rate was 72.2%. Chemical analysis of stones disclosed calcium oxalate-containing stones in 61% and calcium phosphate-containing ones in 10.8%. Recurrence of lithiasis was observed in 18 of the 131 patients (13.7%) who could be followed up for 6 months or more. These results were compared with those obtained after endoscopic treatment at Kinki University.

Adolescent↗