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J Kato

Publications and source records attributed to J Kato.

At least 397 records · Page 22Linked to original sources
PubMed1992

Distribution of cells containing progesterone receptor mRNA in the female rat di- and telencephalon: an in situ hybridization study.

In an attempt to examine regional synthesis of the progesterone receptor (PR) in the brain, the distribution of mRNA encoding PR was investigated in the female adult rat di- and telencephalon by in situ hybridization using T7 RNA polymerase transcripts of a 320 base pair rat PR cDNA clone. The rat PR cDNA had been partially cloned and sequenced by using the reverse transcription-polymerase chain reaction (RT-PCR) method. The primer set corresponds to a part of the progesterone binding domain of human PR cDNA. Large numbers of strong labeling were observed in the arcuate nucleus, medial preoptic nucleus, and ventrolateral part of the ventromedial nucleus which are relative to sexual behavior. Moderate labeling was found in layers II and IV of the isocortex, in the pyramidal layer of the CA1 and CA3 fields of the hippocampal formation, in the cortical nucleus of the amygdala, in the nucleus of the diagonal band, and in the anterior periventricular nucleus. Weak labeling was found in many other regions. These results were largely in agreement with the distribution of PR previously reported by ligand binding assay and autoradiographic studies. This present in situ hybridization study may provide a useful tool for the analysis of the regional regulation of PR synthesis in the rat brain.

Animals↗
PubMed1992

Expression of estrogen receptor in the rat brain: detection of its mRNA using reverse transcription-polymerase chain reaction.

Reverse transcription-polymerase chain reaction (RT-PCR)-Southern blotting was employed for biochemical detection and measurement of the estrogen receptor messenger ribonucleic acid (ERmRNA) in various parts of the Wistar strain female rat brain. Total RNA extracted from the tissues was subjected to RT-PCR using the primer set which flanked the part(287bp) of the estrogen binding domain-corresponding region of the rat ERcDNA. It was confirmed that the RT-PCR product corresponded to the part of the ERcDNA by direct nucleotide sequencing of the product. Moreover, the level of ERmRNA could be determined by Southern blotting which was highly sensitive and produced quantitative results. The RT-PCR product of about 290 bp, corresponding in length to the distance between two primers, was generated from RNA of all the tissues examined. The levels of the product were as follows; anterior hypophysis greater than hypothalamus and preoptic area, amygdala much greater than cerebral cortex, cerebellum. These results indicate that ERmRNA is widely distributed in the whole brain, implying some physiological action of estrogen on target and 'non-target' brain regions.

Animals↗
PubMed1992

Expression of progesterone receptor in the neonatal rat brain cortex: detection of its mRNA using reverse transcription-polymerase chain reaction.

Our previous reports have revealed the postnatal developmental pattern of progesterone receptor (PR) in the rat cerebral cortex, but little is known about PRmRNA changes in the tissue so far. In the present study, we have attempted to detect and quantify PRmRNA in the tissue by the use of the reverse transcription-polymerase chain reaction (RT-PCR)-dot blot analysis. Cerebral cortical tissues were dissected from female Wistar rats at 2 and 8 days of age. Total RNA extracted from the tissues was reverse transcribed, followed by PCR. The PCR primer set, whose sequence was derived from the human clone, flanked the part (320 bp) of the human PRcDNA which corresponded to the progesterone binding domain. The 320 bp of the RT-PCR product was generated from rat uterine RNA. The amino acid sequence deduced from the nucleotide sequence of the product had a 95.5% identity with the corresponding region in human PR, confirming that the product had originated from the rat PRmRNA. Moreover, a highly sensitive and quantitative assay for rat PRmRNA had been developed by the use of RT-PCR-dot blotting. The PRmRNA was detectable in the cerebral cortex of both 2- and 8-day-old rats by the assay. Furthermore, the level of cortical PRmRNA of the 8-day-old rats were greater than the 2-day-old rats. These results indicate that the RT-PCR assay is useful for detection and quantification of PRmRNA in the neonatal rat cerebral cortex, and that increment of the cortical PRmRNA in the 8-day-old rat is associated with a drastic change of the level of the cortical PR around day 10.

Aging↗
PubMed1992

Basic fibroblast growth factor production and growth factor receptors as potential targets for melanoma therapy.

A number of growth factors can stimulate the proliferation of human malignant melanoma cell lines. We investigated the effects of exogenous growth factors including basic fibroblast growth factor (bFGF), epidermal growth factor, transforming growth factor-alpha, insulin, insulin-like growth factor-I (IGF-I), acidic fibroblast growth factor, platelet-derived growth factor, transforming growth factor-beta and nerve growth factor on six human metastatic melanoma cell lines. The mitogenic activity of each growth factor was tested using the [3H]thymidine incorporation assay. There was a variable response of the different cell lines to most growth factors. All of the melanoma cell lines tested responded to IGF-I. Furthermore, the effects of growth factors were additive, a combination of bFGF and IGF-I having the greatest effect on three melanoma cell lines tested. The quantitative radioimmunoassay for bFGF and [125I]bFGF binding assay revealed that all of these melanoma cell lines produced bFGF and expressed high affinity receptors for bFGF. A 20-mer antisense oligodeoxynucleotide against the AUG initiation site of the bFGF coding region inhibited the proliferation of Mel-Tang by 40% (p less than 0.0001) and that of SK-MEL-5 by 20% (p less than 0.005), suggesting that these cell lines are at least under partial autocrine control of proliferation by bFGF. The presence of bFGF receptors on a high percentage of melanoma cell lines makes these a potential target for melanoma therapy.

Base Sequence↗
PubMed1992

Rapid method for analyzing bacterial behavioral responses to chemical stimuli.

A rapid method was developed to analyze bacterial behavioral responses to chemical stimuli. Digital image processing was used to detect the accumulation of bacteria at the mouth of a capillary containing an attractant. The accumulation of bacteria was determined from the total number of cells near the mouth of the capillary per videotape frame. This method was applied to measure the chemotactic response of Pseudomonas aeruginosa cells to serine, with results similar to those obtained by the classical capillary plating assay. The videotape method is much less time-consuming and makes it possible to assess the bacterial response to an attractant within a few minutes.

Journal Article↗
PubMed1992

Phosphate taxis in Pseudomonas aeruginosa.

Pseudomonas aeruginosa was shown to be attracted to phosphate. The chemotactic response was induced by phosphate starvation. The specificity of chemoreceptors for phosphate was high so that no other tested phosphorus compounds elicited a chemotactic response as strong as that elicited by phosphate. Competition experiments showed that the chemoreceptors for phosphate appeared to be different from those for the common amino acids. Mutants constitutive for alkaline phosphatase showed the chemotactic response to phosphate regardless of whether the cells were starved for phosphate.

Alkaline Phosphatase↗
PubMed1992

Difference in effect of atrial natriuretic peptide on cGMP in aortic and coronary smooth muscle cells.

Blood vessels show a heterogeneous response to the atrial natriuretic peptide (ANP). In our experiments thoracic aorta from the guinea pig relaxed in response to atriopeptin III (AP; rat ANP-103-126) and to sodium nitroprusside (SNP). In contrast, in perfused guinea pig hearts, AP III produced no change in coronary flow, while SNP increased flow. In smooth muscle cells cultured from the coronary system (CASM) and from the thoracic aorta (TASM), we compared receptor binding and the effects on guanosine 3',5'-cyclic monophosphate (cGMP) production of AP III. AP III bound specifically with equal affinity and with equivalent numbers of binding sites in both cell types. AP III produced a dose-dependent increase in cGMP in TASM (50% effective concentration approximately 3 nM) with a maximum 11-fold increase over basal at 1 microM AP III. In contrast, in CASM, AP III failed to increase cGMP. Nitroprusside increased cGMP in both cell types. Autoradiograms of 125I-labeled AP III linked to cell membranes showed bands at 70 kDa (ANP-C receptor) in both cell types. A second band at 140 kDa (ANP-B receptor) was only seen in TASM. These results suggest that smooth muscle cells of coronary resistance vessels of the guinea pig do not express the particulate guanylyl cyclase that is activated by ANP.

Animals↗
PubMed1992

Distribution of calcitonin gene-related peptide and substance P-immunoreactive nerve fibers and their correlation in the periodontal ligament of the mouse incisor.

The distribution of calcitonin gene-related peptide (CGRP)- and substance P (SP)-immunoreactive (IR) nerve fibers and their correlation in the periodontal ligament of mouse incisors were examined by indirect immunofluorescence. Both CGRP-IR and SP-IR thin nerve fibers were abundant in the apical and middle third of the periodontal ligament. In the lingual portion of the incisal periodontal ligament, these nerve fibers were localized in the alveolar half of the periodontal ligament and were observed as free nerve endings. No CGRP-IR and SP-IR specialized nerve endings, such as Ruffini-like corpuscles, were observed. In the labial periodontal ligament, CGRP-IR and SP-IR nerve fibers ran along the incisal axis. The distribution of CGRP-IR nerve fibers was very similar to that of SP-IR nerve fibers.

Animals↗
PubMed1992

[Monotherapy with extracorporeal shock wave lithotripsy for renal and ureteral stones].

We performed extracorporeal shock wave lithotripsy (ESWL) as a monotherapy using the Medstone STS lithotripter on 288 patients with renal and ureteral stones between June, 1989 and June, 1991. We compared our results with previous reports on ESWL as used in combination therapy. Our cases consisted of 121 patients with renal stones and 167 patients with ureteral stones. A total of 437 sessions of lithotripsy were performed on 288 patients, for an average of 1.52 sessions of lithotripsy per patient. The percentage of stones measuring less than 4.0 mm in diameter that were fragmented was 94.3% for renal stones and 87.6% for ureteral stones. The stone-free rates 3 months after ESWL were 60.3% and 90.4%, respectively. Our results of the monotherapy with ESWL did not differ from those reported on ESWL as used in combination therapy, in terms of the rate of stone destruction and stone-free rates. We studied the other reports carefully and determined that ESWL monotherapy could have been performed in most those cases. We concluded that ESWL monotherapy is an excellent therapeutic method in the light of fewer complications and side effects compared with those from combination therapy, and the fact that the rate of recurrence for renal and ureteral stones is high makes ESWL monotherapy very useful because the procedure can be repeated.

Adolescent↗
PubMed1992

Circulating transferrin receptor in acute leukemias.

Serum transferrin receptor (s-TR) levels in acute leukemia patients were measured by a recently developed sandwich radioimmunoassay. The mean s-TR level for normal subjects (n = 205) was 246 +/- 79 (mean +/- 1 SD) ng/ml. The values for patients with untreated acute myelocytic leukemia (AML, n = 18) and untreated acute lymphocytic leukemia (ALL, n = 14) were 398 +/- 175 ng/ml and 479 +/- 176 ng/ml, respectively, both of which were significantly higher than those for the normal subjects (AML, p < 0.02; ALL, p < 0.05). When complete remission was achieved with initial remission induction therapy, s-TR decreased to 262 +/- 47 ng/ml (n = 22, 12 AML and 10 ALL), returning to normal levels. There was a good correlation between s-TR levels and the number of leukemic cells in peripheral blood (r = 0.743, n = 32, p < 0.01). In two patients with AML, serial changes of s-TR values and numbers of blast cells in the peripheral blood and bone marrow occurred in a parallel manner. If, therefore, this assay for s-TR can be made more sensitive, it may become useful for assessing acute leukemia activity and for monitoring the effects of therapy.

Acute Disease↗
PubMed1992

[Suppressive effect of sevoflurane on somato-sympathetic reflexes in cats].

Effects of sevoflurane on the reflex activity of the sympathetic nervous system in cats were investigated by observing alteration of the amplitudes of somato-sympathetic medullary reflex potentials. These reflex potentials consist of two components, A- and C-reflex potentials, which are induced from the lumbar sympathetic trunk by electric stimulation of the ipsilateral femoral nerve. It is known that A- or C-reflex potential is induced by stimulating peripheral A-fiber group or C fiber group, respectively. Sevoflurane 1, 2 and 3% in oxygen for 30 minutes for each concentration by incremental fashion, were inhalated. Neither A nor C reflex potentials were suppressed by 1 and 2% sevoflurane but 3% sevoflurane caused a significant suppression of both reflex potentials in brain intact cats. Concentration-dependent suppression of C-reflex potentials and a tendency of concentration-dependent suppression of A-reflex potentials were observed in decerebrate cats. Mean arterial blood pressure showed a concentration-dependent decrease in both brain intact and decerebrate groups. These results indicate that sevoflurane with concentrations higher than 1 MAC (2.5% for cats) significantly suppresses somato-sympathetic reflex activities. The results suggest, however, that this agent with concentrations lower than 1 MAC suppresses the descending inhibitory system from supra-medullary centers so that the integrated sympathetic outflow from the medulla oblongata are not suppressed significantly. The results also suggest that direct depressive effect on the cardiovascular system by sevoflurane rather than through suppressive effect on sympathetic reflexes may play a major role in hypotension during inhalation of concentrations below 1 MAC.

Action Potentials↗
PubMed1992

[A case report of ruptured aneurysm of the sinus Valsalva resulted in tricuspid valve endocarditis].

A case of a 42-year-old man with ruptured aneurysm of the sinus Valsalva resulted in tricuspid valve endocarditis was reported. The aneurysm originating from the right sinus Valsalva ruptured into the right atrium, which caused tricuspid valve endocarditis. The aneurysm was closed through right atrial approach. A part of the septal leaflet of tricuspid valve including vegetation was resected and repaired.

Adult↗
PubMed1992

[Combined revascularization of coronary and femoral arteries].

A 63-year-old male patient with both coronary artery disease and leg ischemia was successfully treated with a combined procedure. Coronary arteries were bypassed with the saphenous vein graft and in situ left internal mammary artery, and bilateral femoral arteries were bypassed with expanded polytetrafluoroethylene grafts descended from the ascending aorta through the preperitoneal abdominal wall tunnel. After this procedure he experienced neither angina nor claudication.

Anastomosis, Surgical↗
PubMed1992

[The determination of basic fibroblast growth factor (bFGF) in human placental tissue and the changes in bFGF during pregnancy].

The purpose of this study is to develop an assay system for quantification of bFGF in human tissue and to investigate the changes in bFGF content in the human placenta during pregnancy. Sixty-two placental tissue samples from various stages of normal pregnancies were collected. Approximately 28 micrograms bFGF was obtained per 1 kg of placental tissue. The recovery rates were 17.1 +/- 7.4%. The purified samples were confirmed as bFGF by SDS-PAGE and enzyme-linked immunoelectrotransfer blot (EITB) with anti-human bFGF monoclonal antibody. The bFGF readings in the human placenta determined by RIA were 11.81 +/- 2.11 fmol/mg protein (first trimester), 20.45 +/- 4.85 (early second trimester), 9.52 +/- 5.02 (late second trimester), 7.41 +/- 2.07 (third trimester), and 7.75 +/- 1.86 (post trimester). The placental bFGF were significantly high in the early stage of second trimester and declined gradually during the remainder of the pregnancy. The RIA values were correlated closely with the values obtained by bioassay. These results demonstrate that our assay system provides a tool for the quantification of bFGF in biological samples and suggest that bFGF, the active mitogen and angiogenic factor, participates in the formation of the human placenta.

Angiogenesis Inducing Agents↗
PubMed1992

[Immunohistochemical study of collagen type III in adenomyosis].

To clarify the mechanism of the origin of adenomyosis, we investigated the immunohistochemical distribution of collagen type III in the human endometrium and the adenomyosis throughout the menstrual cycle. 1) Collagen type III was localized in the stroma of normal endometrium and ectopic endometrium, and in the myometrium. No staining of collagen type III was observed in the endometrial gland. 2) The intensity of staining for collagen type III in the basal layer of normal endometrium was stronger than those in the functional layer. The staining in the proliferative phase was stronger than that in the secretory phase. 3) The intensity of staining of collagen type III in ectopic endometrium paralleled that in the basal layer of normal endometrium. 4) The intensity of staining of collagen type III in the myometrium did not change throughout the menstrual cycle. These results suggest that close similarities exist between stromal cells in normal endometrium and in ectopic endometrium from the viewpoint of the extracellular matrix.

Collagen↗