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A Akiyama

Publications and source records attributed to A Akiyama.

At least 19 recordsLinked to original sources
PubMed2001

Primary signet-ring cell carcinoma of the urinary bladder inducing renal failure.

A case of primary signet-ring cell carcinoma of the urinary bladder that was found to have induced renal failure is the second such case reported in the world. Primary signet-ring cell carcinoma of the urinary bladder is a rare histologic variant of adenocarcinoma. The patient died of distant metastasis 8 months after undergoing total cystectomy. The neoplasm had a high stage at diagnosis, so the prognosis was very poor. To improve the prognosis, earlier diagnosis and establishing a regimen of chemotherapy is necessary.

Carcinoma, Signet Ring Cell↗
PubMed2001

M1 prostate cancer with a serum level of prostate-specific antigen less than 10 ng/mL.

BACKGROUND: M1 prostate cancer, which is invasive, is usually associated with a serum level of prostate-specific antigen (PSA) greater than 10 ng/mL, but cases are occurring where the serum PSA level is less than this. The present study investigated the clinical and pathologic characteristics of these cases of M1 prostate cancer. METHODS: Between April 1989 and March 1998, 167 cases of M1 prostate cancer were diagnosed by transrectal needle biopsy and eight of these with a serum PSA level less than 10 ng/mL were investigated. The patients' ages ranged from 57 to 79 years (median, 73) and the serum PSA levels ranged from less than 4.0 to 9.8 ng/mL. In all cases except one, the distal metastasis was to bones only. All cases had received hormonal therapy as the initial therapy. Immunostaining of PSA, chromogranin A, neuron-specific enolase, carcinoembryonic antigen and vimentin were performed in five of the eight cases. RESULTS: Four cases were poorly differentiated, two were undifferentiated, one was a mixture of poorly differentiated and undifferentiated and one case was moderately differentiated. Of the five cases in the immunohistochemical study, three cases with an undifferentiated carcinoma component showed negative staining reactions for PSA and all cases were positive for carcinoembryonic antigen. Four of the patients died of prostate cancer. In two of these four cases, hormonal therapy was ineffective, but systemic chemotherapy and irradiation therapy had been moderately effective. The overall 3-year survival rate was 33.3%. CONCLUSIONS: The cases of M1 prostate cancer with a serum PSA less than 10 ng/mL are almost always poorly differentiated or undifferentiated and have a poor prognosis compared with the usual M1 prostate cancer. Because hormonal therapy is ineffective in these cases, systemic chemotherapy and irradiation therapy should be chosen as the initial therapy.

Aged↗
PubMed2001

In vitro refolding of porcine pepsin immobilized on agarose beads.

Since in vitro refolding of pepsin has long been attempted without success, it has been suspected that pepsin has no intrinsic refolding ability. In the present study, in order to eliminate unfavorable intermolecular interactions bringing about aggregation and autoproteolysis, we immobilized pepsin onto agarose beads. This technique enabled us to search extensively for appropriate refolding conditions without limitation of the refolding period. Renaturation of immobilized pepsin was observed exclusively at pH 3-5. This process was extremely slow and reached equilibrium after 300 h. Sixty percent of the proteolytic activity was recovered at pH 5. Addition of salts raised the recovery to 80% but had no significant effect on the refolding rate, suggesting that the salts mainly stabilize the native state of pepsin. This is the first report on the successful in vitro refolding of pepsin.

Animals↗
PubMed2001

P-113D, an antimicrobial peptide active against Pseudomonas aeruginosa, retains activity in the presence of sputum from cystic fibrosis patients.

Antimicrobial peptides are a source of novel agents that could be useful for treatment of the chronic lung infections that afflict cystic fibrosis (CF) patients. Efficacy depends on antimicrobial activity against the major pathogens of CF patients, Pseudomonas aeruginosa, Staphylococcus aureus, and Haemophilus influenzae, in the environment of the CF patient's airway. We describe the in vitro efficacies of derivatives of histatins, which are histidine-rich peptides produced by the salivary glands of humans and higher primates. P-113, a peptide containing 12 of the 24 amino acid residues of the parent molecule, histatin 5, retained full antibacterial activity and had a good spectrum of activity in vitro against the prominent pathogens of CF patients. However, P-113 was not active in the presence of purulent sputum from CF patients. In contrast, P-113D, the mirror-image peptide with the amino acid residues in the D configuration, was stable in sputum, was as active as P-113 against pathogens of CF patients in the absence of sputum and retained significant activity in the presence of sputum from CF patients. Recombinant human DNase, which effectively liquefies sputum, enhanced the activity of P-113D in undiluted sputum against both exogenous (added) bacteria and endogenous bacteria. Because of its properties, P-113D shows potential as an inhalant in chronic suppressive therapy for CF patients.

Anti-Bacterial Agents↗
PubMed2000

Urothelial cytoprotective activity of Tamm-Horsfall protein isolated from the urine of healthy subjects and patients with interstitial cystitis.

PURPOSE: Tamm-Horsfall protein (THP) is a ubiquitous urinary protein with essentially no known function. We propose that THP is a cytoprotective agent that protects the urothelium from cationic species. To test this hypothesis we isolated THP from normal and interstitial cystitis urine to see if it could protect cultured cells from damage induced by the polyamine, protamine sulfate (PS). METHODS: Tamm-Horsfall protein was extracted from the urine of interstitial cystitis (IC) patients (N=28) and normal volunteers (N=5). Urothelial target cells (T24) were radiolabeled with 51Cr and then exposed to PS (0-1.0 mg/mL) for either 1.5 or 20 h. The resulting cytotoxicity data (dose-response curves) were then compared with the data obtained when PS was preincubated with 0-0.5 mg/mL of THP (IC vs normal), the semisynthetic polysaccharide, pentosan polysulfate (Elmiron), or human serum albumin. RESULTS: Toxicity of PS was significantly reduced by incubation with THP (or Elmiron) prior to evaluation by the chromium release assay, but not reduced by incubating with another protein, albumin. Tamm-Horsfall protein from IC patients' urine was less protective than an equal quantity of THP from normal urine. CONCLUSIONS: These experiments suggest that THP has an important role in bladder mucosal defense mechanisms, protecting the bladder surface from injury. Inability of THP to prevent cytotoxic damage by urinary polyamine or other urinary toxins (cationic species) may be relevant in the etiology of interstitial cystitis, as putative urinary toxic components have been described in the urine of some patients.

Adjuvants, Immunologic↗
PubMed1999

High-speed voltammetry: dual measurement of dopamine and serotonin.

A high-speed voltammetric system was designed and tested for dual measurement of dopamine (DA) and serotonin (5-HT) at 250-ms intervals. First, an anodic-cathodic square-wave pulse was delivered to activate the electrode (carbon fiber, 7 microm in diameter), then DA and 5-HT oxidation currents (current intensity) were measured when potentials were stepped from 100 to 250 mV and 300 to 450 mV, respectively. To isolate DA and 5-HT current intensities, the current observed at 100 mV was subtracted from that at 250 mV, and the current observed at 300 mV was subtracted from that at 450 mV, respectively. Measurements were performed every 250 ms. In vitro, DA and 5-HT current intensities increased with increasing concentrations of DA and 5-HT, respectively. The DA current intensity was not affected by the addition of the DA metabolite 3,4-dihydroxyphenylacetic acid (10(-6) M) or ascorbic acid (10(-5) M), but the 5-HT current intensity was affected by the addition of the 5-HT metabolite 5-hydroxyindoleacetic acid (10(-6) M) or uric acid (10(-5) M). Electrodes were used for several months without any change in sensitivity. In vivo, following intraperitoneal injection of L-DOPA to rats, an increase in striatal DA release was observed but there was no increase in release of 5-HT. Following intraperitoneal injection of 5-hydroxytryptamine there was an increase in 5-HT release but not DA release. This high-speed system was capable of obtaining stable, long-term dual measurements of DA and 5-HT in vitro and in vivo.

3,4-Dihydroxyphenylacetic Acid↗
PubMed1999

Cloning, expression of the psbU gene, and functional studies of the recombinant 12-kDa protein of photosystem II from a red alga Cyanidium caldarium.

The encoding extrinsic 12-kDa protein of oxygen-evolving PS II complex from a red alga, Cyanidium caldarium, was cloned and sequenced by means of PCR and a rapid amplification of cDNA ends (RACE) procedure. The gene encodes a putative polypeptide of 154 amino acids with a calculated molecular mass of 16,714 Da. The full sequence of the protein includes two characteristic transit peptides, one for transfer across the chloroplast envelope and another for targeting into the thylakoid lumen. This indicates that the protein is encoded in the nuclear genome. The mature protein consists of 93 amino acids with a calculated molecular mass of 10,513 Da. The cloned gene was successfully expressed in Escherichia coli and the resulting protein was purified, reconstituted to CaCl2-washed PS II complex together with the other extrinsic proteins of 33 and 20 kDa and cyt c-550. The recombinant 12-kDa protein bound completely with the PSII complex, which resulted in a restoration of oxygen evolution equal to the level achieved by binding of the native 12-kDa protein.

Amino Acid Sequence↗
PubMed1999

Radiological states around the Kraton-4 underground nuclear explosion site in Sakha.

A radiological survey around the site of Kraton-4, an underground nuclear explosion (Yield of 20 kt, depth of 560 m, 1978) in Sakha was carried out in March 1998. Gamma survey and in-situ spectroscopy on the ground exhibited quite normal levels: a dose rate of 0.022 microSv/h and Cs-137 surface contamination of less than 1.1 kBq/m2 around the hypocenter. The results suggested no remarkable leakage of radioactivity from the epicenter to the ground surface at least not for non-rare gas elements as of 1998.

Dose-Response Relationship, Radiation↗
PubMed1999

[Histopathological effect and its predictors of neoadjuvant hormonal therapy by combined androgen blockade].

OBJECTIVES: Combined androgen blockade (CAB) uning LH-RH agonist and flutamide has been performed as neoadjuvant therapy for T 2, 3 prostate cancers (CaP). The histological effects of neoadjuvant CAB therapy and influential factors were investigated. METHODS: Materials were 20 CaP cases which were underwent radical prostatectomy (RP) after neoadjuvant CAB therapy. All cases were diagnosed by echo-guided sextant needle biopsies. RP was performed after serum PSA was decreased to undetectable level. Histological effect was evaluated by general rule for clinical and pathological studies on prostate cancer (Japanese Urological Association). All cases were divided 2 groups by histological effects as follows: Group A (poor effect group): G 0 and G 1, Group B (good effect group): G 2 and G 3. Immunostaining of p 53 (mutant type), bcl-2 and Chromogranin A (ChA) were performed for both pretreatment needle biopsy and RP specimen. In addition, pretreatment serum PSA and Gleason grade were also investigated. RESULTS: Down grading were found in 30%. Down staging were found in 35% (7 cases). All 7 cases were negative surgical margins and 5 of 7 were clinical T 3. Negative bcl-2 of biopsy specimen was correlation with down grading (p = 0.008). In the histopathological evaluation, G 0 was 1, G 1 were 10, G 2 were 6 and G 3 were 3 cases. Gleason 4 or 5 elements of biopsy were found in 9/11 cases in Group A but only 3/9 cases in Group B (p = 0.027). The bcl-2 positive cells of biopsy were found in 8/11 cases in Group A but only 1/9 cases in Group B (p = 0.006). The p 53 and/or bcl-2 positive cells of biopsy were found in 10/11 cases in Group A but only 3/9 cases in Group B (p = 0.007). Serum PSA and ChA were not correlation with histological effect of neoadjuvant CAB therapy. But, in 3 cases, ChA positive cell appeared after neoadjuvant therapy. CONCLUSIONS: We could not expect more than 50% cases to show the down grading and down staging. But, in T 3 case, surgical failure could be decrease. We could expect prostate cancer cases without positive bcl-2 cells, p 53 over expression and Gleason 4 x 5 to reveal the good histological effects of neoadjuvant CAB therapy.

Androgen Antagonists↗
PubMed1999

[Management of mycobacteriosis in general hospital without isolation ward for tuberculosis patients. 2. The problems of management of the patients diagnosed pulmonary tuberculosis after admission to the respiratory ward of university hospital having no an isolation ward for the tuberculous patients].

The management of 28 patients, diagnosed pulmonary tuberculosis by bacteriological or pathologic findings after the administration to the Koshigaya Hospital of Dokkyo university school of Medicine from January 1994 through September 1997, which had no an isolation ward for tuberculosis patients was analyzed. The mean age of the patients was 50.6 +/- 16.7 (18-85), and the number of male and female patients was 22 and 6 respectively. The underlying diseases found in 10 patients were gastric cancer, breast cancer, osteochondrosarcoma, collagen disease, diabetes mellitus, liver cirrhosis, pneumoconiosis, and bronchial asthma. Two patients were complicated by a lung cancer. Six of 28 patients showed smear-positive and culture-positive specimens and 22 of 28 patients showed smear-negative and culture-positive specimens. The detection of mycobacterial DNA in the samples after amplification by the polymerase chain reaction (PCR) used in 15 patients and was positive for 7 of 15 patients. The pathological study of the specimens obtained by Transbronchial lung biopsy was performed for 14 patients. The pathological findings were compatible with tuberculosis in 7 of 14 patients. The chief complaints of the 11 patients admitted to the hospital with in 3 days after first visit, were fever in all patients and in 5 patients with pleural effusion. A few patients showed smear-negative and PCR positive specimens and complicated by lung cancer or other malignancy, were treated in non isolation ward in the particular case of emergency evacuation before admission, careful examination such as a tuberculin test, bacterial examination, and PCR of sputum should be performed in the patients suspected of having pulmonary tuberculosis. The patients isolating tubercule bacilli after administration should be transferred to the hospital with isolated ward for tuberculosis or isolated room in general hospital in the particular case of emergency evacuation with the greatest care.

Adolescent↗
PubMed1998

The dopamine D2 receptor antagonist sulpiride causes long-lasting serotonin release.

The effects of the dopamine D2 receptor antagonist sulpiride on extracellular levels of serotonin (5-hydroxytryptamine, 5-HT) and the 5-HT metabolite 5-hydroxyindoleacetic acid (5-HIAA) were examined by using in vivo voltammetry. Sulpiride (1 or 3 mM, 2 microl over 24 min) was administered to freely moving rats via a cannula implanted in the striatum and 5-hydroxyindole levels were measured by using a carbon fiber voltammetry electrode implanted in the ipsilateral striatum. Six to 8 h after injection, 5-hydroxyindole levels increased 3-fold, peaked 1 to 2 days post-injection, and returned to normal levels within 2 to 4 days. These effects were suppressed by pretreatment with p-chlorophenylalanine. Two days after sulpiride injection, high-performance liquid chromatography of striatal homogenates revealed that although the 5-HT concentration was unchanged, the 5-HIAA concentration was increased significantly. These results suggest that the long-lasting elevation of 5-hydroxyindole concentrations was primarily due to increased 5-HT release.

Animals↗
PubMed1998

Differential time courses of exogenous 1-methyl-4-phenyl-1,2,3, 6-tetrahydropyridine and its metabolite MPP+ in the rat striatum and nucleus accumbens measured using in vivo voltammetry.

The dopaminergic neurotoxin 1-methyl-4-phenyl-1,2,3, 6-tetrahydropyridine (MPTP) has been shown to affect nigrostriatal projection neurons to a greater extent than substantia nigra neurons that project to the nucleus accumbens. To investigate this preferential vulnerability, the intracerebral pharmacokinetics of locally-applied MPTP was investigated using in vivo voltammetry. First, we examined whether MPTP and MPP+ were measurable in vitro. At the most efficient oxidation potential for MPTP (850 mV), its metabolite MPP+ was also partly oxidized, whereas at that for MPP+ (650 mV), MPTP was not oxidized. Then, in vivo measurements were taken less than 1 mm from the site of infusion of MPTP. MPTP and endogenously produced MPP+ peaked later and took longer to return to baseline in the nucleus accumbens than in the striatum. Systemic monoamine oxidase-B inhibitor pargyline delayed the peak and return to baseline of endogenously produced MPP+ in the nucleus accumbens. Exogenously applied MPP+ also took longer to peak and return to baseline in the nucleus accumbens. These results indicate that the difference in the pharmacokinetics of exogenously applied MPTP in the striatum and nucleus accumbens may be due to a difference in uptake in these regions, and that the difference in pharmacokinetics of endogenously produced MPP+ may be due to differences in both uptake and monoamine oxidase-B activity.

1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine↗
PubMed1998

Immediate and long-term effects of 5,7-dihydroxytryptamine on rat striatal serotonergic neurons measured using in vivo voltammetry.

The immediate and long-term effects of the selective serotonergic neurotoxin 5,7-dihydroxytryptamine (5,7-DHT) on rat striatal serotonergic neurons were examined after its intracerebroventricular administration using in vivo voltammetry. Extracellular concentration of 5-hydroxyindoles increased immediately following intracerebroventricular 5,7-DHT injection (200 microg in 24 microl, 18 min), peaked at 1.5-2 h, and returned to normal by 4 h. 5,7-DHT diffused to the contralateral striatum in detectable amounts 9 to 12 min after the start of injection and returned to basal levels by 1.5 h. Three to 6 days after 5,7-DHT lesions, 5-hydroxytryptophan administration produced an increase in striatal 5-hydroxyindoles that was greater than that produced in pre-lesioned rats. This effect was maximal at 14 to 17 days post-lesion, and remained even after 50 days. The short-term effect of 5,7-DHT may be attributable to increased serotonin release, inhibition of uptake, or monoamine oxidase inhibition. The long-term effect of 5,7-DHT lesions may attributable to increased synthesis of serotonin or decreased reuptake in remaining serotonergic neurons.

5,7-Dihydroxytryptamine↗
PubMed1997

In vivo electrochemical measurement of the long-lasting release of dopamine and serotonin induced by intrastriatal kainic acid.

Intrastriatal injection of the glutamate agonist kainic acid (KA) in rats has been used to produce an animal model to investigate the mechanism of acetylcholine and GABA cell death associated with Huntington's disease. In the present study, the time course of low (10(-5) M) and high (5 x 10(-3) M) concentrations of KA on striatal dopamine and serotonin release was studied in freely moving rats by using in vivo voltammetry. The response to low concentrations of KA varied between animals, either increasing dopamine release during the injection or increasing dopamine and serotonin after the injection for an extended time, suggesting that 10(-5) KA is near the threshold for KA toxicity in the striatum in rats. High concentrations of KA suppressed dopamine release during injection, with both dopamine and serotonin release increasing and remaining elevated for 1-4 and 7-21 days, respectively. KA-induced changes were inhibited by 6-cyano-7-nitroquinoxaline-2,3-dione and bicuculline increased the release of dopamine but not serotonin. These findings suggest that KA-induced changes in dopamine release resulted from a disinhibition of dopamine neurons due to KA-mediated toxicity of striatal GABA neurons. An alternate possibility is that the change in dopamine and serotonin release may have arisen from a functional modification or degeneration of presynaptic terminals.

3,4-Dihydroxyphenylacetic Acid↗
PubMed1996

[Image cytometric DNA analysis in bladder tumors].

UNLABELLED: We studied image cytometric DNA analysis of bladder tumors to evaluate malignant potentials of bladder tumors. METHODS: Thirty nine samples were obtained by TUR from 37 patients. Nuclear DNA content of all samples were measured by image cytometer and were determined ploidy pattern by DNA histogram. RESULTS: Of 39 TCC non-diploid pattern was recognized in 50% of grade 1 cases, 73% of grade 2 cases and 100% of grade 3 cases. DNA ploidy was strictly correlated with histological grading in TCC. DNA non-diploid pattern was present in 67% of papillary tumors, 87.5% of non-papillary tumors and 100% in CIS. In diploid pattern 2 of 7 cases with grade 1 and 2 of 4 cases with grade 2 recurred. In non-diploid pattern 1 of 4 cases with grade 1, 4 of 10 cases with grade 2 and 4 of 6 cases with grade 3 recurred. There was no significant correlation between diploid and non-diploid pattern in grade 1, 2, 3. CONCLUSION: Image cytometric DNA analysis may be useful in addition to the classic and prognostic parameters of stage and grade, especially in TCC. The differences between image analysis system and flow cytometric analysis for DNA measurement were discussed.

Adult↗
PubMed1996

[A case report of ileovesical fistula in radiation enteritis].

A 49-year-old female was admitted with chief complaint of fecaluria on March 4th 1993. A radiation therapy had been performed for uterocervical cancer 18 years ago. The small intestine and bladder was detected by DIP- and cystogram simultaneously. It was diagnosed as an ileovesical fistula. A segmental resection of the ileum with partial cystectomy was performed on March 23rd. Histopathologically, the ileum showed a radiation enteritis. Eventually, we diagnosed that this ileovesical fistula was caused by radiation. After operation, an incompletion of suture occurred. So we made an ileostomy secondarily and performed hyperbaric oxygen therapy. The patient was getting well temporarily but died of gastric hemorrhage on May 1st.

Female↗
PubMed1995

A clinical and immunohistochemical study of papillary adenocarcinoma of the prostate.

Clinical and immunohistochemical studies were conducted to evaluate prostatic papillary adenocarcinoma and prostatic papillary hyperplasia. Subjects consisted of 5 cases of papillary adenocarcinoma and 2 cases of papillary hyperplasia. There is no conclusive clinical factor for preoperative diagnosis, but we attach importance to endoscopic findings. PSA, PAP, high molecular weight cytokeratin, and PCNA were evaluated immunohistochemically. PSA became positive in every instance but one--a case of papillary adenocarcinoma which became +/-. PAP was + in all cases, except for 1 case of papillary adenocarcinoma. Basal cells were positive for high molecular weight cytokeratin in 2 cases of papillary hyperplasia but were missing in papillary adenocarcinoma. Although PCNA was free from positive nuclei in papillary hyperplasia, positive nuclei were found in all cases of papillary adenocarcinoma. Considering these immunohistochemical results, papillary adenocarcinoma can be said to originate in the glandular epithelium of the prostate, as does ordinary prostatic carcinoma.

Acid Phosphatase↗