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Biomedical subjects

M Akimoto

Publications and source records attributed to M Akimoto.

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

Alpha-fetoprotein producing undifferentiated carcinoma of the bladder.

We report on a rare primary undifferentiated carcinoma of the bladder producing alpha-fetoprotein in a woman. Definitive features included an aggressive, invasive and rapidly growing tumor with a hepatoid carcinomatous lesion on histological examination. Histopathological findings suggested that the multipotent transitional cell induces production of alpha-fetoprotein. The association of an aggressive tumor with the ability to produce this antigen suggests a possible benefit in measuring serum alpha-fetoprotein levels and examining histological sections for its expression in primary undifferentiated carcinoma of the bladder. Further study may indicate radical cystectomy when the resected specimen produces alpha-fetoprotein, particularly if tumors appear to be aggressive and highly vascularized as in our case.

Aged↗
PubMed1994

[Fine structural studies on the cytoplasmic membrane morphology of transitional cell carcinoma in men].

Transitional cell carcinomas (TCC) in the human urinary bladder were observed on the fine morphological behaviour of the plasma membrane, with special references to the morphological differences in various grades of TCC utilizing thin sections and freeze fracture replica electron microscopically. The purpose of this study is to clarify the characteristic differences between various grades of human TCC as a indicator suggestive of the TCC malignancy using electron microscopic techniques. (1) The asymmetric unit membrane seen on the luminal membrane of the superficial cells was unique in all of TCC G1 and some TCC G2 cases. In other TCC G2 and TCC G3, there observed the symmetric unit membrane. Fusiform vesicles directly beneath the luminal plasma membrane were recognized only in TCC G1. (2) Microvilli (MV) seen on the luminal plasma membrane in TCC G1 were found to have the same appearance and distribution as on the normal bladder epithelium. As the grades increased in severity, there were less MV being shorter and club-like-forms. Even deformed with bleb formation microvilli were more apparent in TCC G3 cases than in TCC G2. (3) There was no difference observed between the junctional complex of the superficial cells of the all TCC grades and normal cells. As the cellular malignancies develop, however, the interdigitation structures and desmosomal appearances situated between neighboring intermediate cells tended to decrease. (4) Intracytoplasmic tonofilaments proliferation was obvious in TCC G2, but not in G3. (5) With increasing severity of TCC grades, intramembranous particles showed significant decrease in number as seen on freeze-fracture replica. In conclusion, these results suggest that fine structural observation may prove to be a useful parameter to know the grades of TCC in human bladder tumors.

Carcinoma, Transitional Cell↗
PubMed1994

[Semi-radical transurethral resection of the prostate for small benign prostatic hyperplasia].

The conventional method of transurethral resection of the prostate (TUR-P) is often not beneficial for small benign prostatic hyperplasia (BPH) because of a high frequency of postoperative bladder neck contracture (BNC). Herein, we examined the usefulness of semi-radical transurethral resection of the prostate (semi-radical TUR-P) from the view points of improvement of peak flow rate, the frequency of postoperative BNC and incidental carcinoma of the prostate in 79 cases of small BPH (group A) and 101 cases (group B) of large BPH in which less than 10 g for more than 10 g of the internal glands was resected, respectively. The bladder neck was resected carefully to avoid over resection which may cause BNC in small BPH cases. Satisfactory results were obtained in both groups, that is, the improvement of the peak flow rate from 7.03 +/- 3.79 ml/sec to 13.9 +/- 7.32ml/sec and from 4.96 +/- 2.88 ml/sec to 15.2 +/- 8.30 ml/sec, and the frequency of BNC were 2.53% (2/79) and 1.98% (2/101) in groups A and B, respectively. The frequency of incidental carcinoma of the prostate were 15.2% (12/79) and 17.8% (18/101) in groups A and B. We conclude that semi-radical TUR-P is a favorable maneuver for small BPH because of satisfactory improvement in peak flow rate with low frequency of postoperative BNC and its superiority in screening test for incidental carcinoma of the prostate.

Aged↗
PubMed1994

[Clinical treatment of urinary tract stones with Alexandrite laser].

Clinical treatment of urolithiasis with Alexandrite-laser which is a solid pulse laser system developed in Switzerland is reported. Two cases of renal stones, 3 cases of vesical stones, and 35 renal units in 34 cases of ureteral stones were treated. The approach to the aimed stone was, percutaneous to the renal stones, and transurethral to the vesical and ureteral stones. The clinical success rate was 92.5% (37/40), when we defined success as the endoscopically observed fragmentation. The uric acid stone in the bladder was not disintegrated even when the plasma occurred, but the ureteral uric acid stone was easily fragmented. The difference was thought to be attributed to the condition of the surface. The Alexandrite-laser system generates a 750 nm wavelength, and this wavelength is neither absorbed in water nor hemoglobin, so is thought to be harmless to the tissue. Actually, if misirradiation to the ureteral mucosa during lithotripsy was done, neither plasma formation nor perforation occurred. In conclusion, the Alexandrite-laser is thought to be safe and effective equipment for the treatment of urolithiasis.

Adult↗
PubMed1993

Surgical effects of trabeculotomy ab externo on adult eyes with primary open angle glaucoma and pseudoexfoliation syndrome.

OBJECTIVES: Retrospective and prospective studies examined the surgical effects in lowering intraocular pressure levels of trabeculotomy ab externo in adult eyes with either primary open angle glaucoma or pseudoexfoliation syndrome. We report the results of primary trabeculotomy as an intervention for glaucoma. PATIENTS: Included in the retrospective study were 357 eyes of 227 patients with primary open angle glaucoma and 82 eyes of 65 patients with pseudoexfoliation syndrome, each of which underwent trabeculotomy ab externo alone and none of which had a history of laser or surgical treatment for ocular disease. Included in the prospective study were 33 eyes of 22 patients with primary open angle glaucoma and 17 eyes of 15 patients (older than 40 years) with pseudoexfoliation syndrome. RESULTS: A life-table analysis for the retrospective study showed that the final success probability (mean +/- SE) at 5 years after surgery was 73.5% +/- 6.3% in eyes with pseudoexfoliation syndrome, which is significantly better than 58.0% +/- 3.1% in eyes with primary open angle glaucoma (P < .05). Also, the higher the preoperative intraocular pressure levels are, the less likely that the postoperative intraocular pressure levels will be brought under control (P < .01). Surgical outcome in the prospective study demonstrated success in 27 (79%) of 34 eyes after 3 years and in 16 (64%) of 25 eyes after 5 years, with medication. Complications included Descemet's membrane detachment (one eye), cyclodialysis (one eye), and decreased visual acuity due to progression of cataract (four eyes). CONCLUSION: The surgical results of trabeculotomy ab externo remain effective in controlling intraocular pressure levels for a long time in selected patients. It thus appears that trabeculotomy ab externo can be considered as an alternative choice of surgical treatment in some cases of glaucoma.

Adult↗
PubMed1993

Long-term indwelling bilateral ureteral stents for bilateral hydronephrosis of unknown etiology.

We describe a rare case of long-term indwelling bilateral ureteral stents that were replaced yearly for 7 years because of azotemia associated with bilateral hydronephrosis of undetermined etiology on radiological examinations. During year 5 the patient had an uneventful gestation with delivery of a normal neonate by cesarean section. Hydronephrosis remained improved for 2 years after withdrawal of the stents.

Adult↗
PubMed1993

Macrophages in the urine in acute bacterial cystitis.

In the previous study in this series of studies concerning the role of macrophages in urinary tract infection, we attempted to detect macrophages in the urine of acute bacterial cystitis patients by nonspecific esterase staining of urinary sediment, however none of the leukocytes stained, probably because of cell damage caused by the urine and by centrifugation. In the present study, detection of macrophages in urine was again attempted, this time by prompt transfer of urinary leukocytes to culture medium after minimum centrifugation, 1 hr culture in a glass bottom chamber and non-specific staining of leukocytes adhering to glass. Macrophages in urine were detected by this method, and they comprised 5.9% of the adherent leukocytes, although macrophage spreading, which implies macrophage activation and is often seen in the early stage of nonbacterial prostatitis, was hardly ever observed. The percentages of adherent leukocytes were not correlated with urine osmolarity, probably because the effect of urine was minimized by prompt transfer of urinary leukocytes to culture medium after the urine samples had been collected. There have been quite few studies involving culture of urinary leukocytes in the past. Our simple techniques, such as prompt transfer of urinary leukocytes to culture medium after centrifuging with minimum gravity and for a minimum period of time, appear to be useful in the study of urinary leukocytes using other cells which appear in urinary tract infection, as well as cytokines and antibiotics, to clarify cellular mechanisms of defenses in urinary tract infection.

Acute Disease↗
PubMed1993

Effects of soft X-ray irradiation on ocular development in Sprague-Dawley rats.

Pregnant rats were irradiated with soft x-rays at a dose of 1.6, 3.2, 6.3 or 12.6 Gy on Day 9 of gestation, and the eyes of F1 offspring were examined using indirect ophthalmoscopy and biomicroscopy during Postnatal Week 5. Ophthalmoscopic examination revealed iris and choroidal coloboma, microphthalmia and anophthalmia in the 3.2, 6.3 and 12.6 Gy groups. In addition to those anomalies, lens luxation and associated anterior displacement of the vitreous face, and retinal vascular anomalies were observed in the 12.6 Gy group. Histological examination revealed agenesis of retinal vessels. Ophthalmoscopic examination using biomicroscopy and indirect ophthalmoscopy detected choroidal coloboma, lens and vitreous luxation and defect in retinal vessels which could not be detected by external observation, demonstrating the usefulness of this technique in the postnatal stage of teratology studies.

Animals↗
PubMed1993

[Characterization of primary and metastatic cell lines established from a patient with renal cell carcinoma].

We established four renal cell carcinoma (RCC) cell lines (HANKS), namely the primary tumor (HANKS-Pr), metastasized to the lung (HANKS-Lu), liver (HANKS-Li) and lymph node (HANKS-LN) derived from a patient with advanced RCC, and analyzed their characters. Each had an epithelial morphology and exhibited multilayering. These cell lines have been maintained for more than 36 months and over 100 in vitro passages. In karyotype analysis, the common aberration in the four cell lines was marker chromosome t (3;18) (p13;q21). In soft agar culture, HANKS-Pr showed the lowest growth. Furthermore, we found high level expression of major histocompatibility complex (MHC) class I antigen on HANKS-Pr and HANKS-Lu, and low expression of MHC class II antigen on four cell lines. HANKS-LN had transplantability in nude mice. We determined the different biological properties among HANKS cell lines stemming from the same origin.

Adult↗
PubMed1993

[Clinical application of transrectal ultrasonic therapy to nonbacterial prostatitis and prostatodynia cases which were resistant to conventional drug therapy].

A total of 25 patients with nonbacterial prostatitis and prostatodynia which were resistant to conventional drug therapy underwent 5 minutes course of transrectal ultrasonic therapy in association with application of 1% hydrocortisone acetate cream to the anterior rectal wall for consecutive 8 days. The efficacy of the treatment was evaluated only by comparison of symptom scores for subjective symptoms obtained before and after treatment. Excellent results, which were defined as more than 70% reduction of symptom scores after treatment, were obtained in 5 (27.8%) among 18 evaluable cases in which symptom scores before treatment were more than 4, good (40-69% reduction of scores) in 4 (22.2%), fair (10-39% reduction of scores) in 4 (22.2%) and poor (less than 10% reduction of scores) in 5 (27.8%). Because of good clinical efficacy and the absence of complication, transrectal ultrasonic therapy combined with hydrocortisone acetate cream application was thought to be useful for the treatment of nonbacterial prostatitis and prostatodynia cases which responded poorly to the conventional therapy.

Administration, Topical↗
PubMed1993

Investigation of the clinical value of assessing renal size on computed tomography in autosomal dominant polycystic kidney disease.

We examined relationship between serum creatinine concentration (Scr) and renal size on CT scans on 32 occasions in 25 patients with autosomal dominant polycystic kidney disease (ADPKD). As a result, a significant correlation was observed when the Scr was less than 5 mg/dl, as shown by the correlation coefficient (r) and P values of 0.803 and 0.0001, respectively. However, these values changed to 0.482 and 0.0093, respectively when 2 cases with Scr 6.2 and 6.4 mg/dl were included, and further changed to 0.005 and 0.9775 when an additional 4 cases with Scr 7.8, 9.9, 11.1 and 20.1 mg/dl were included. Renal size is therefore thought to be a useful parameter of renal function when the Scr is less than 5 mg/dl in ADPKD, but not when the Scr exceeds 6 mg/dl, and is regarded as useless for predicting the time at which dialysis would be required.

Creatinine↗
PubMed1993

[Ectopic prostatic tissue in the bladder].

A 55-year-old man with a 5-year history of microhematuria had a whitish sessile tumor at the ureteric ridge containing benign prostatic glandular tissue. The presence of benign prostatic polyps in the prostatic urethra is a common finding, but ectopic prostatic tissue elsewhere is rare, it has been described previously in a few cases in the trigonum. The origin of prostatic glands in this unlikely location is not yet fully understood. Prostatic tissue at any ectopic location is benign, although local recurrence has been reported. We reviewed 43 cases of ectopic prostatic tissue, 7 of which occurred in bladder include our case, reported in the Japanese literature. Ectopic prostatic tissue should be considered in the differential diagnosis of hematuria in the male.

Choristoma↗
PubMed1992

Computed tomographic evaluation of bone metastases in prostatic cancer patients.

This report provides new morphological insights, based on diagnostic methods, into metastases to the bone in prostate cancer patients. Lumbar CT examination is available to evaluate whether metastases are truly present or not, especially in aged patients with positive bone scans. The evaluation of response is clearer on CT. Furthermore, CT is useful not only in estimating the presence of metastases, CT also provides definite details on the extent of the metastatic condition.

Aged↗
PubMed1992

New morphological changes induced by FK506 in a short period in the rat kidney and the effect of superoxide dismutase and OKY-046 on THEM: the relationship of FK506 nephrotoxicity to lipid peroxidation and change in production of thromboxane A2 in the kidney.

Juxtaglomerular (JG) hyperplasia and tubular damage along with a decrease in the urine creatinine level induced by FK506 in rat kidney have already been reported in previous paper by us. In this paper, we document the relationship of FK506 nephrotoxicity to the change in the production of thromboxane (Tx) A2 and the lipid peroxidation of the cellular membrane in the rat kidney in order to clarify its morphogenesis. The urinary excretion of TxB2 increased with FK506 administration even on day 1 (P < 0.02). Histologically, OKY-046 (thromboxane synthetase inhibitor) decreased tubular damage, although JG hyperplasia was not eradicated, while biochemically the excretion of TxB2 decreased significantly (P < 0.02), and both the decrease in the urine creatinine level and the increase in the N-acetyl-beta,D-glucosaminidase (NAG) index were relatively smaller. Although the FK506-induced morphological and biochemical changes could not be prevented by the continuous administration of superoxide dismutase (SOD) 30,000 U/kg daily, the malondialdehyde content in renal tissue removed 1 h after FK506 administration had increased. These data suggest that FK506 nephrotoxicity is related to the change in the production of TxA2 and lipid peroxidation of the cellular membrane. However, other mechanisms such as the involvement of sympathomimetic effects of FK506 and other vasoconstrictive factors cannot be ruled out.

Acetylglucosaminidase↗
PubMed1992

Relationship between endothelin and thromboxane A2 in rat liver microcirculation.

In our previous study, we determined changes in hepatic blood flow using a Laser Doppler blood flow meter after i.v. injection of endothelin-1 (ET-1) or endothelin-3 (ET-3) at 2 nmol/kg in rats and found that ET-3 caused greater decreases in blood flow than ET-1. In the present study, we determined how the arachidonic acid cascade, mainly thromboxane A2 (TXA2), is related to ET-1 and ET-3 using indomethacin (INDO), which inhibits the biosynthesis of prostaglandin (PG), and OKY-046, a selective inhibitor of TXA2 synthesis. In the first series of experiments, ET-1 and ET-3 were administered after inhibiting the biosynthesis of PG by s.c. injection of 2 mg/kg of INDO. While INDO failed to inhibit the slight decrease in hepatic blood flow induced by ET-1, it significantly inhibited the marked decrease in hepatic blood flow elicited by ET-3. In the next series of experiments, ET-1 and ET-3 were administered after administration of 20 mg/kg of OKY-046. OKY-046 showed no effects in animals treated with ET-1, as in those pre-treated with INDO, while it significantly inhibited the decreases in hepatic blood flow induced by ET-3. These findings suggest that ET-1 decreases hepatic blood flow due to its direct effects although to a lesser extent than ET-3, while ET-3 does so due not only to its direct effects but also to TXA2-mediated effects. It is therefore likely that in addition to ET family peptides, PG-mediated mechanisms are involved in the regulation of hepatic microcirculation by ETs.

Animals↗
PubMed1992

ET-3 sensitive reduction of tissue blood flow in rat liver.

Changes in gastric mucosal and hepatic tissue blood flow were simultaneously determined using a laser-Doppler blood flow meter in rats given i.v. injection of endothelin-1 (ET-1) and endothelin-3 (ET-3), both at 2 nmol/kg. Gastric mucosal blood flow decreased significantly after administration of ET-1 compared to after administration of ET-3. Decreases in blood flow due to ET-1 were reversed by pre-treatment with 10 mg/kg of BQ-123 (sodium salt), an ETA receptor antagonist, to levels comparable to those induced by ET-3, but BQ-123 had no effects on decreases in blood flow due to ET-3. On the other hand, decreases in hepatic tissue blood flow by ET-3 were significant compared to those by ET-1. Decreases in hepatic tissue blood flow due to ET-1 were slightly inhibited by pre-treatment with 10 mg/kg of BQ-123, but it had no effect at all on decreases due to ET-3. These findings indicate that decreases in gastric mucosal blood flow are mainly caused by ET-1 via ETA receptors inhibited by BQ-123, while decreases in hepatic tissue blood flow are caused mainly by ET-3 via non-ETA receptors not inhibited by BQ-123. The fact that ET-3 decreases blood flow more significantly than ET-1 suggests the involvement of ET-3 selective receptors (ETc). The findings obtained in the present study indicate that complex mechanisms are involved in the regulation of tissue blood flow by ET, with different receptor subtypes and ET family peptides being involved according to the type of tissue.

Animals↗
PubMed1992

Metabolism of L-amino acids in a marine bacterium isolated from mackerel intestines in relation to eicosapentaenoic acid biosynthesis.

Metabolism of glucose and L-amino acids in an obligately aerobic marine bacterium isolated from Pacific mackerel intestines was investigated for the mechanism and pathway of eicosapentaenoic acid (EPA) biosynthesis. This bacterium could not uptake glucose but the cell-free extract of this bacterium had the enzymatic activities of L-alanine oxidase (EC 1.4.3.2), L-alanine dehydrogenase (EC 1.4.1.1). L-serine dehydratase (EC 4.2.1.13), and malate dehydrogenase (EC 1.1.1.40), and of seven enzymes involved in the TCA cycle of the usual aerobes. On the other hand, the carbon-13 concentration in cellular fatty acids of the bacterium, especially that in their methyl carbon atoms in contrast to their carbonyl carbons, increased drastically when the bacterium was grown in the presence of 13CH3COONa. These results indicate that: (i) the TCA cycle works in this bacterium, (ii) glucose is not utilized and pyruvic acid is in vivo synthesized from L-alanine, L-serine, and malic acid, and (iii) EPA and other cellular fatty acids are in vivo synthesized from acetyl coenzyme A by the usual de novo synthesis route.

Amino Acids↗