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Biomedical subjects

H Morikawa

Publications and source records attributed to H Morikawa.

At least 37 records · Page 2Linked to original sources
PubMed2001

[A case of Bellini duct carcinoma producing granulocyte colony-stimulating factor (G-CSF)].

A case of Bellini duct carcinoma producing granulocyte colony-stimulating factor (G-CSF) is reported. The patient was a 75-year-old female with the chief complaint of appetite loss. Abdominal ultrasonography and abdominal computed tomography revealed left renal pelvic tumor. Left radical nephrouretrectomy was performed. The histopathological report showed Bellini duct carcinoma. Immunohistochemical staining using the anti-G-CSF antibody showed positive staining in the cancer cells. Preoperatively, the white blood cell count and serum G-CSF concentration were elevated to 34,100/microliter and 334 pg/ml respectively. After operation these values became normal. However, these values were elevated again and CT scan revealed a left pulmonary metastasis 3 months after the operation. In spite of chemotherapy, she died of brain metastases 7 months after the operation.

Adenocarcinoma, Papillary↗
PubMed2000

Surface hardness changes induced by O-, Ca- or P-ion implantation into titanium.

Titanium or titanium alloys are very attractive biomedical materials. Biocompatible elements of oxygen, calcium and phosphorus were implanted into titanium and changes of surface hardness were measured using an ultra micro indenter (UMIS-2000). A multiple load-partial unload procedure that can reveal a hardness versus depth profile was adopted. Depth profiles of concentration of implanted ions were obtained by SIMS measurement. For O and P implantation, it is observed that the hardness increases with the increases in the dose. O implantation produced the largest increase in hardness, up to 2.2 times higher than the unimplanted titanium. On the other hand, Ca implantation produced only a small increase in the hardness that was independent of the ion dose. The surface oxide layer of a Ca implanted titanium sample was much thicker than the unimplanted samples or those implanted with O and P ions. The depth of maximum hardness increases with increasing energy of implanted ions. The depths of the maximum hardness occur at indentation depths of one-third to one-eighth of the mean ranges of implanted ions.

Journal Article↗
PubMed2000

Frequent altered expression of fragile histidine triad protein in human colorectal adenomas.

Fragile histidine triad (FHIT) gene is involved in deletions on the short arm of chromosome 3 in various human cancers. We found that 47% of colorectal adenomas, which is a higher frequency than that of K-ras, showed altered expression of the Fhit protein by Western blot analysis. The amount of Fhit protein was inversely correlated with the degree of dysplasia. Importantly, 27% of low-grade dysplastic adenomas showed altered expression of Fhit protein. Additionally, expression of human Fhit protein in human colon carcinoma cell line SW480 exhibited a marked inhibition of growth and rendered SW480 cells highly susceptible to undergo apoptosis compared with control cells. These findings suggest that altered expression of the FHIT gene is a quite early aberration in the development of colorectal tumors and that Fhit protein may act as a tumor suppressor.

Acid Anhydride Hydrolases↗
PubMed2000

Inositol 1,4,5-triphosphate-evoked responses in midbrain dopamine neurons.

Synaptically released glutamate evokes slow IPSPs mediated by metabotropic glutamate receptors (mGluRs) in midbrain dopamine neurons. These mGluR IPSPs are caused by release of Ca(2+) from intracellular stores and subsequent activation of small-conductance Ca(2+)-activated K(+) channels (SK channels). To further investigate the intracellular mechanisms involved, the effect of photolyzing intracellular caged inositol 1,4,5-triphosphate (InsP(3)) on membrane conductance and intracellular Ca(2+) concentration ([Ca(2+)](i)) was examined in rat midbrain slices. Photolytic release of InsP(3) elicited a transient outward current and a sharp rise in [Ca(2+)](i) that lasted for approximately 5 sec. Apamin, a blocker of SK channels, abolished the InsP(3)-induced outward current without affecting the rise in [Ca(2+)](i). Depleting intracellular Ca(2+) stores with cyclopiazonic acid completely blocked both the outward current and the Ca(2+) transient elicited by InsP(3). InsP(3)-evoked Ca(2+) mobilization was not affected by blockade of ryanodine receptors with ruthenium red, whereas depleting ryanodine-sensitive Ca(2+) stores with ryanodine almost eliminated InsP(3)-induced Ca(2+) release. Increasing the size of intracellular Ca(2+) stores by means of prolonged depolarization added a late component to the outward current and a slow component to the rising phase of [Ca(2+)](i). These effects of depolarization were blocked by ruthenium red. These results show that InsP(3) activates SK channels by releasing Ca(2+) from InsP(3)-sensitive stores that also contain ryanodine receptors. Increasing intracellular Ca(2+) stores boosts InsP(3)-evoked responses by invoking Ca(2+)-induced Ca(2+) release through ryanodine receptors. This intracellular signaling pathway may play a significant role in regulating the excitability of midbrain dopamine neurons.

Animals↗
PubMed2000

Ion-chromatographic behavior of alkali metal cations and ammonium ion on zirconium-adsorbing silica gel.

The preparation and evaluation of zirconium-adsorbing silica gel (Zr-Silica) as an ion-exchange stationary phase in ion chromatography for inorganic anions and cations was carried out. The Zr-Silica was prepared by the reaction of silanol groups on the surface of the silica gel with zirconium butoxide (Zr(OCH2CH2CH2CH3)4) in ethanol. The ion-exchange characteristics of the Zr-Silica were evaluated using 10 mM tartaric acid at pH 2.5 as eluent. The Zr-Silica was found to act as a cation-exchanger under the eluent conditions. The retention behavior of alkali and alkaline earth metal cations was then investigated. The Zr-Silica column was proved to be suitable for the simultaneous separation of alkali metal cations and ammonium ion. Excellent separation of the cations on a 15 cm Zr-Silica column was achieved in 25 min using 10 mM tartaric acid as eluent.

Alkalies↗
PubMed2000

Sublobular veins as the main site of lymphocyte adhesion/transmigration and adhesion molecule expression in the porto-sinusoidal-hepatic venous system during concanavalin A-induced hepatitis in mice.

Lymphocyte infiltration is a manifest feature of hepatitis. To reveal the main site and mechanism of lymphocyte adhesion/extravasation in the hepatic vasculature during inflammation, we morphometrically and histologically analyzed these events in relation to adhesion molecule expression using a murine model of T-cell mediated hepatitis induced by concanavalin A (Con A). Although lymphocyte adhesion was restricted to the sinusoids in untreated mice, it increased in all the segments of porto-sinusoidal-hepatic venous system 8 hours after Con A injection; the number of adhering lymphocytes per unit vascular circumference was the largest in the sublobular veins, relatively large in the central veins and small hepatic veins, and relatively small in the sinusoids and negligible in the portal veins. At 20 hours, extravascular lymphocytes showed similar distribution to lymphocyte adhesion at 8 hours except in the portal veins, around which they were possibly accumulated by the translocation of extrasinusoidal lymphocytes. E-selectin and vascular cell adhesion molecule-1 (VCAM-1) were transiently expressed at 4 to 6 hours, whereas P-selectin and intercellular adhesion molecule-1 were not changed between 0 and 48 hours. In particular, E-selectin expression coincided with that of lymphocyte adhesion in distribution. Lymphocyte attachment was inhibited by pretreatment with anti-E-selectin monoclonal antibody (MAb) or anti-VCAM-1 MAb, and expression of E-selectin and VCAM-1 was suppressed by pretreatment with anti-tumor necrosis factor-alpha (TNF-alpha) MAb. Electron microscopically, lymphocytes were trapped by endothelial lamellipodia and traversed the endothelium by diapedesis. These results indicate that lymphocyte adhesion/transmigration preferentially takes place in the sublobular veins in association with TNF-alpha-induced endothelial activation, i.e., E-selectin and VCAM-1 expression and lamellipodia formation.

Animals↗
PubMed2000

Alteration of colonic mucin after ureterosigmoidostomy.

PURPOSE: Patients undergoing urinary diversion by ureterosigmoidostomy after complete cystectomy for malignant bladder tumors show a high incidence of neoplasia at and near the site of anastomosis. We examined a risk factor for tumor occurrence in the area of anastomosis, alterations of mucus glycoproteins in the surrounding colonic mucosa. METHODS: Colonoscopy was performed in 37 patients who had undergone ureterosigmoidostomy. Biopsy specimens were obtained near the ureteral anastomosis and were stained with hematoxylin and eosin, high iron-diamine alcian blue (pH 2.5), and a fluorescent lectin conjugate (peanut agglutinin). RESULTS: At the anastomotic site colonoscopy showed protruding lesions in 26 of 37 patients (71 percent), all histologically representing inflammatory granulomas. The mucosa around the anastomosis was normal in endoscopic appearance; however, histologically, slight inflammatory cell infiltration, edema, and increased numbers of Paneth cells were observed. Alcian blue staining revealed an increase in mucosal sialomucin postoperatively compared with preoperatively. The proportion of peanut agglutinin-binding mucin, not observed in normal mucosa but seen in malignant or premalignant tissue, was increased. CONCLUSION: As postoperative interval increases, changes in properties of the "background" mucosa become greater, which suggests an association with colonic carcinogenesis.

Adult↗
PubMed2000

Acquired ileal diverticulum: an unusual bleeding source.

Acquired ileal diverticulum is an uncommon condition and diagnosis is often difficult when bleeding occurs from this source. Here we describe two cases of ileal diverticulum with massive bleeding. Both patients presented with anal bleeding, but upper and lower gastrointestinal endoscopy did not reveal the source. Selective visceral angiography finally detected bleeding lesions in the terminal ileum. Surgical resection was performed in both patients, confirming that the bleeding arose from diverticula less than 1 cm in size. In patients with obscure gastrointestinal bleeding, an ileal diverticulum should be considered, and selective visceral angiography should be performed for precise diagnosis.

Aged↗
PubMed2000

The role of costimulatory molecules (B7-1 and B7-2) on allergen-stimulated B cells in cedar pollinosis subjects.

BACKGROUND: B7-1 (CD80) and B7-2 (CD86), which are costimulatory molecules in T-cell activation, play important roles in the differentiation of TH1- or TH2-phenotypes. These molecules were also suggested to play important roles in sensitization to a cedar pollen antigen by blocking studies using neutralizing antibodies, but there have been very few studies concerning the effects following induction by antigen. OBJECTIVE: In this study, we investigated the roles of B7-1 and B7-2 in the differentiation of TH1 and TH2 subsets after stimulation with the antigen in subjects with cedar pollinosis. METHODS: Skin-prick test was performed in nine subjects with pollinosis and in nine normal controls. Peripheral blood mononuclear cells (PBMCs) were isolated and stimulated with Japanese cedar pollen extract. After in vitro stimulation, the expression of CD80 and CD86 on CD19+ cells was analysed by two-colour flow cytometry. Culture supernatants were collected for all subjects and the production of type 1 and type 2 cytokines was measured by ELISA. RESULTS: After in vitro stimulation, the expression of CD80 (B7-1) was upregulated in both pollinosis and control subjects, but no significant difference was observed between the two groups. On the other hand, CD86 (B7-2) was significantly upregulated following stimulation in pollinosis subjects (P = 0.02). A significantly higher level of IL-5 (P = 0.04) was produced by PBMCs of pollinosis subjects than by those of normal controls. A significantly higher level of interferon (IFN)-gamma (P = 0.03) was produced by PBMCs of normal controls than by those of pollinosis subjects. CONCLUSION: These results indicated that TH2 response was predominant in pollinosis subjects, and that CD19+ cells of pollinosis subjects expressed higher levels of B7-2 than those of control subjects after in vitro stimulation. In pollinosis subjects, B7-2 rather than B7-1 may be the costimulatory molecule involved in allergen-induced activation of PBMCs.

Adult↗
PubMed2000

Unresponsiveness of intrahepatic lymphocytes to bacterial superantigen: rapid development of suppressive Mac-1(high) cells in the mouse liver.

We previously found that a small dose (2 microg per mouse) of staphylococcal enterotoxin B (SEB) induced early emerging unresponsiveness in intrahepatic-lymphocyte populations (IHLs). The purpose of this study was to reveal the inducing role of accessory cells involved in IHLs in this phenomenon. IHLs prepared at 3 to 24 hours after SEB injection failed to proliferate in response not only to SEB but also to SEA, representing ligand-nonspecific unresponsiveness, whereas spleen cells (SPCs) and mesenteric lymph-node cells showed transient proliferation. Unresponsiveness in IHLs was related to a deficit of their accessory cell function as measured by coculture of irradiated IHLs and antigen-specific, type 1 T-helper (Th1) clone cells. High levels of nitrite were detected in the culture supernatant. Supplement of N(G)-monomethyl-L-arginine lowered nitrite levels and concurrently restored the proliferative response of Th1 cells, indicating the involvement of nitric oxide in suppression. Adherent cells prepared from IHLs well reproduced these results. As shown by flow cytometry, Mac-1(high) Ia(+) cells, which mainly included F4/80(+) cells (macrophages) and a minor population of CD11c(+) cells (dendritic cells), increased in proportion in IHLs but not in SPCs at 6 to 24 hours. Depletion of Mac-1(high) cells from IHLs with antibody-coated magnetic beads recovered the proliferative response. Depleted Mac-1(high) cells had a monocytoid appearance. In immunostained sections, Kupffer cells came to highly express both Mac-1 and Ia at 12 hours. These results indicate that Mac-1(high)Ia(+) adherent cells, largely Kupffer cells activated by SEB, nonspecifically suppress the proliferation of Th1 cells via nitric oxide production before manifestation of ligand-specific unresponsiveness.

Animals↗
PubMed2000

Laparoscopic microwave coagulation therapy for hepatocellular carcinoma.

BACKGROUND AND STUDY AIMS: Several different effective forms of treatment are available, singly or in combination, for patients with hepatocellular carcinoma (HCC). These include surgical resection, transcatheter arterial embolization, percutaneous ethanol injection, and percutaneous microwave coagulation therapy. In this study, we carried out laparoscopic microwave coagulation therapy (LMCT), using laparoscopic microwave electrodes to treat HCC. PATIENTS AND METHODS: Under local anesthesia, 24 patients with HCCs located on or near the liver surface underwent LMCT under direct laparoscopic vision, with ultrasound guidance. LMCT was performed using microwave electrodes with tips ranging from 15-45 mm in length, and the effectiveness of the treatment was confirmed using contrast-enhanced computed tomography (CT) within two weeks of the LMCT procedure. RESULTS: The mean longest axis of the 26 HCC nodules in 24 patients was 20 mm, and that of the coagulated areas including the nodules was 40 mm, with additional therapy being required in two patients. Complete efficacy of the treatment was observed in 21 patients (87.5%), but local recurrences were seen in three of them one year after LMCT. The three-year survival rate was 92%, but the number of patients included in the study was small. Hemostasis was complete, but mild pneumothorax occurred in three patients. CONCLUSIONS: LMCT under local anesthesia is a minimally invasive and effective therapy when carried out on a single occasion to treat HCCs located near the liver surface, and it can be safely performed under direct visual guidance.

Aged↗
PubMed2000

On the grain boundary segregation of Sn in indium-tin-oxide thin films

The determination of Sn segregation by means of electron energy loss spectroscopy and X-ray photoelectron spectroscopy has been attempted on indium-tin-oxide thin films prepared by various processes: (a) as-deposited at room temperature; (b) after annealing at 533 K in vacuum; (c) after annealing in air; and (d) as-deposited at 473 K. The occurrence of Sn segregation both at the surface and at the grain boundary was proved. The degree of segregation detected, varied depending on the preparation process of the films.

Journal Article↗
PubMed2000

Assessment of hepatic blood flow by PET with 15O water: correlation between per-rectal portal scintigraphy with 99Tc(m)-pertechnetate and scintigraphy with 99Tc(m)-GSA.

We performed positron emission tomography with 15O water (H2(15)O) to measure hepatic arterial and portal blood flow. In addition, portal haemodynamics and hepatic functional reserve were measured by per-rectal portal scintigraphy and scintigraphy with galactosyl human serum albumin, respectively. We studied 15 patients who had cirrhosis of the liver with underlying viral infection. After the intravenous injection of H2(15)O, positron emission tomography was performed. Blood samples were obtained after beginning the emission scan. The blood samples and positron emission tomographic images were analysed to calculate the radioactivity in the blood and liver. One-compartment model analysis was used to estimate hepatic arterial and portal blood flow. Computer acquisition of gamma-camera data was started just before the injection of 99Tc(m)-galactosyl human serum albumin. A receptor index and an index of blood clearance were calculated on the basis of the radioactivity of the liver and heart. A 99Tc(m)-pertechnetate solution was instilled into the rectum; serial scintigrams were performed and radioactivity curves for the liver and heart were recorded sequentially. A per-rectal portal shunt index was calculated from the curves. Median portal blood flow was 80 ml x 100 g(-1) x min(-1), median hepatic arterial blood flow was 56 ml x 100 g(-1) x min(-1), and median total hepatic blood flow was 138 ml x 100 g(-1) x min(-1) in patients with cirrhosis. The correlations between portal blood flow and the Child-Turcotte classification score, portal shunt index and receptor index were all significant. Our results show that hepatic arterial and portal blood flow can be measured by positron emission tomography with H2(15)O non-invasively and physiologically. This technique may be useful in pathophysiological studies of liver disease.

Hepatitis, Viral, Human↗
PubMed2000

Regulation of central synaptic transmission by 5-HT(1B) auto- and heteroreceptors.

Although 5-HT(1B) receptors are believed to be expressed on nerve terminals, their precise mode of action is not fully understood because of the lack of selective antagonists. The 5-HT(1B) receptor knockout mouse was used in the present investigation to assess the function of 5-HT(1B) receptors in the modulation of synaptic transmission in three areas of the central nervous system: the dorsal raphe, the ventral midbrain, and the nucleus accumbens. N-(3-Trifluoromethylphenyl)piperazine, a 5-HT(1B) receptor agonist, potently inhibited 5-HT(1A) receptor-mediated slow inhibitory postsynaptic potentials (IPSPs) in the dorsal raphe of wild-type but not knockout mice. Both synaptically released 5-HT and exogenous 5-HT caused a presynaptic inhibition that outlasted the postsynaptic hyperpolarization only in wild-type mice. In the ventral midbrain, 5-HT(1B) receptor-dependent inhibition of gamma-aminobutyric acid(B) IPSPs in dopamine neurons was present in wild-type animals and absent in knockout animals. Similar results were obtained in the nucleus accumbens measuring glutamate-mediated excitatory postsynaptic currents in medium spiny neurons. Finally, cocaine, which blocks 5-HT uptake, inhibited IPSPs in the dorsal raphe and the ventral midbrain of wild-type but not knockout mice, whereas cocaine produced comparable inhibition of excitatory postsynaptic currents in the nucleus accumbens of both types of animals. These results indicate that 5-HT(1B) receptors function as autoreceptors and heteroreceptors to exert presynaptic inhibition of transmitter release in the central nervous system. Furthermore, this study underscores the role played by presynaptic 5-HT(1B) receptors in mediating the effects of cocaine on synaptic transmission.

Animals↗
PubMed2000

Comparison of tests for fecal lactoferrin and fecal occult blood for colorectal diseases: a prospective pilot study.

OBJECTIVE: This prospective pilot study was conducted to compare the usefulness of measuring fecal lactoferrin (Lf) to that of fecal occult blood (FOB) test for detection of colorectal diseases. PATIENTS AND METHODS: The subjects were 351 patients who underwent colonoscopy. A fecal sample was obtained on the day before colonoscopy. Fecal Lf was measured by enzyme-linked immunosorbent assay. The FOB test was performed by combined assay (latex agglutination) of hemoglobin and transferrin. RESULTS: The specificities of the fecal Lf and FOB tests were the same (88.7%). For patients with colorectal cancer (13), colorectal polyp (69), ulcerative colitis (18), Crohn's disease (13), non-specific colitis (8), internal hemorrhoids (60), colon diverticulum (27), and miscellaneous diseases of the colon (10), the rates of positivity for fecal Lf were 7/13, 14/69, 12/18, 7/13, 4/8, 22/60, 8/27, and 6/10, respectively. The corresponding rates for FOB were 8/13, 12/69, 11/18, 4/13, 4/8, 9/60, 2/27, and 1/10. For patients with internal hemorrhoids, the rate of positivity for fecal Lf was significantly higher than that for FOB. In other disease groups, there was no significant difference in the rate of positivity between fecal Lf and FOB. CONCLUSION: These findings suggest that measurement of fecal Lf is as useful as FOB in detecting colorectal diseases.

Colonic Diseases↗
PubMed2000

[Follow-up study related to raising low-birth-weight infants relationship among physical growth, mental development and child-rearing anxiety].

OBJECTIVE: In order to clarify relationship among physical growth, mental development of low-birth-weight (LBW) infants and child-rearing anxiety of mothers, a follow-up study was accomplished for LBW cases from birth to three years of age in a regional group. METHODS: A self-administered questionnaire survey was conducted for mothers whose premature infants were born from April 1992 through March 1993 and whose existence was confirmed from April 1995 through March 1996 in Fukui prefecture. A control group was selected from mature infants whose gestation was 37 weeks or more, who were born in the same year and in the same region. The questionnaire was focused on fetal and child growth, as well as child-rearing anxiety. RESULTS: Of the subjects, while including only 6% very LBW infants, the percentage of full-term LBW infants was 55.3% and that of pre-term LBW infants was 44.7%. In the former group, the mean birth weight (MBW) was 2,319 g, the percentage of females was 63.3%, firstborn children was 59.2%, and light-for-dates (LFD) infants due to intrauterine growth retardation 76.9%. In the latter group, the MBW was 1,983 g, the percentage of females was 52.9%, that of firstborn children was 44.5%, and LFD infants was 14.3%. The growth of the LBW infants through the age of three fell into the same category of growth as the upper portion (1,250-1,499 g) of the very LBW infants rather than that of the mature infants. While the growth of appropriate-for-dates (AFD) infants at full-term were normal, that of LFD infants and pre-term infants was insufficient, and the percentage of those demonstrating catch-up of mature infants was less than 80%. The group of pre-term infants was retarded in the gross motor skills, but not language understanding and pronunciation of two-word sentences. The child-rearing anxiety in mothers who delivered pre-term infants was extremely severe after child birth. As the child grew older, however, the feeling of uneasiness was reduced. Mothers who were delivered of full-term LBW infants did not exhibit any fluctuation in child-rearing anxiety during the first three years. CONCLUSION: Fetal size affects growth progress of children. The prognosis of LBW infants is not satisfactory and mothers who deliver full-term LBW infants continue to worry about their child's growth.

Anxiety↗
PubMed1999

Recurrent cerebral infarctions and del(10)(p14p15.1) de novo in HDR (hypoparathyroidism, sensorineural deafness, renal dysplasia) syndrome.

We report on a Japanese boy with HDR syndrome (hypoparathyroidism, sensorineural deafness, renal dysplasia) and recurrent cerebral infarctions in the basal ganglia. The patient experienced cerebral infarctions four times between age 7 months and age 20 months. Chromosome analysis of the patient demonstrated a 46,XY, del(10)(p14p15.1) de novo. This suggests that the putative gene responsible for HDR syndrome is located at 10p14-p15.1.

Adult↗