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Biomedical subjects

M Iwamura

Publications and source records attributed to M Iwamura.

At least 37 records · Page 2Linked to original sources
PubMed1999

[Implication of two additional lateral peripheral zone biopsy in the detection of prostate cancer].

BACKGROUND: Despite the strenuous efforts in improving detection of prostate cancer, no standard technique for prostatic biopsy has been established to date. Extended tissue sampling in peripheral zone may possibly lead to enhanced prostate cancer detection. METHODS: Four hundred thirty-three candidates for ultrasound-guided prostatic biopsy were alternately assigned to two groups regarding biopsy techniques between January 1997 and June 1998, Group A, sextant biopsy group and Group B, two additional lateral peripheral zone sampling after standard sextant biopsy. The outcomes of prostatic biopsy were compared. RESULTS: Cancer detection rates were 19.2% (43/217) in Group A and 18.5% (40/216) in Group B. No statistically significant difference was noted (p > 0.05). Clinical stage, Gleason score and the presence of metastasis did not differ significantly between groups (p > 0.05). The incidence and duration of hematuria, hematospermia were essentially the same between groups (p > 0.05). High fever due to possible bacteremia developed only in Group B patients (p = 0.04). CONCLUSIONS: Routine use of additional peripheral zone biopsy is not recommended owing to the equivalent cancer detection rates between groups. The application of additional biopsy should be determined carefully since this may lead to increased incidence of serious complications.

Aged↗
PubMed1999

[Extragonadal seminoma with testicular microlithiasis: a case report].

A 43-year-old men presented with left supraclavicular growing mass. Ultrasonography revealed a 31 x 21 mm solid mass with a homogeneous echoic pattern. Lymph node metastasis of some malignant neoplasms was highly suspected. However, whole body evaluation with computed tomographic scan revealed no findings in the primary region. In addition, tumor markers including alpha fetoprotein, human chorionic gonadotropin and carcinoembryonic antigen were within normal limits. Then, extirpation of supraclavicular mass was performed and pathological diagnosis was made as pure seminoma. Evaluation of testicle by ultrasonography revealed a diffuse calcification. However, histological examination of biopsy specimen of testicle revealed no malignancy. The mass was finally diagnosed as extragonadal or "burned-out" pure seminoma. The patient received two courses of Peplomycin, vinblastine and cisplatin (PVP) therapy, and there has been no evidence of recurrence for 34 months.

Adult↗
PubMed1998

Caged compounds of a 2-deoxyglucose: facile synthesis and their photoreactivity.

An o-nitrobenzyl and an o-nitrophenethyl derivatized 2-deoxyglucose (caged 2-deoxyglucoses) were synthesized from 3,4,6-tri-O-acetyl-D-glucal in only two steps in moderate to good yields as isomeric mixtures, which were irradiated at 350 nm to afford a 2-deoxyglucose. Decomposition of the o-nitrophenethyl derivative upon photolysis proceeded more efficiently than that of the o-nitrobenzyl derivative.

Deoxyglucose↗
PubMed1998

Characterization of the cell-specific expression of parathyroid hormone-related protein in normal and neoplastic prostate tissue.

OBJECTIVES: Parathyroid hormone-related protein (PTHrP) is a primary factor in the pathogenesis of malignancy-associated hypercalcemia. By alternative splicing, the human PTHrP gene can generate three different species of mRNA that encode three initial translational isoforms of 139, 173, and 141 amino acids. We recently reported that PTHrP was present in normal prostatic neuroendocrine cells and was overexpressed in prostate cancer tissue as demonstrated by immunostaining. This study was undertaken to further clarify the complex expression of PTHrP gene in normal prostate tissue and prostate cancer. METHODS: PTHrP mRNA in samples prepared from normal prostate tissue, prostate cancer, and three prostate cancer cell lines, PC3, LNCaP, and DU145 was assessed using Northern hybridization. Expressed PTHrP isoforms were deduced from differential reverse transcription-polymerase chain reaction (RT-PCR) assays with exon-specific primers. Further localization of different species of PTHrP mRNA was performed using nonradioactive in situ hybridization with exon-specific probes on consecutive sections of normal and neoplastic prostate tissue. RESULTS: Northern hybridization showed that the PTHrP expression level was higher in prostate cancer than in normal prostate tissue. All three PTHrP isoforms could be detected in normal prostate tissues and prostate cancer with differential RT-PCR. Further analysis using in situ hybridization with exon-specific probes revealed that all three PTHrP isoforms were present in prostatic neuroendocrine cells and only PTHrP-1-139 isoform could be clearly detected in prostate cancer tissue. Two androgen-insensitive cell lines, PC3 and DU145, derived from a bone metastasis and a brain metastasis, respectively, expressed all three mRNA species encoding for the three isoforms, but DU145 cells expressed less than PC3 cells. Androgen-sensitive LNCaP cells exhibited a low level of expression of mRNA species encoding for PTHrP-1-139 and PTHrP-1-173, and no expression of PTHrP1-141 isoform. CONCLUSIONS: All three initial translational isoforms of PTHrP are produced by prostatic neuroendocrine cells. The mature products of PTHrP might exert their effects on other prostatic epithelial cells in a paracrine fashion and also participate in the homeostatic regulation of the ejaculate. In prostate cancer, differential expression of these three isoforms is evident and PTHrP-1-139 isoform is more abundant than the other two forms. These findings are valuable for designing future research studies to further elucidate the biological functions of PTHrP in normal prostatic glands and prostate cancer.

Blotting, Northern↗
PubMed1998

Clinical outcome of high-intensity focused ultrasound for treating benign prostatic hyperplasia: preliminary report.

OBJECTIVES: To preliminarily summarize the clinical outcomes of the transrectal high-intensity focused ultrasound procedure using the prototype Sonablate (HIFU1) and the new Sonablate-200 (HIFU2) for treating symptomatic benign prostatic hyperplasia. METHODS: We treated 35 and 22 patients with HIFU1 and HIFU2, respectively. Preoperative and postoperative evaluations were made using the International Prostate Symptom Score (IPSS), quality of life (QOL) data, and the results of uroflowmetry and transrectal ultrasound, and any complications were noted. RESULTS: IPSS and QOL scores showed significant improvement after using both HIFU1 and HIFU2 at 3, 6, and 12 months, postoperatively (P < 0.0001 to < 0.01; Wilcoxon signed-ranks test). Maximum flow rate (8.9 to 15.5 mL/s, P < 0.001) and prostatic volume (32.2 to 22.8 mL, P < 0.01) were significantly improved at 12 months postoperatively in patients who underwent HIFU2 treatment but not in patients who underwent HIFU1. Two hematospermia and one gross hematuria in patients treated with HIFU1 and one epididymitis in a patient treated with HIFU2 were seen but no severe complications were noted. CONCLUSIONS: Focused ultrasound is an effective new technology by which tissue can be destroyed at a site distant from the source of energy without damaging surrounding tissue. The clinical efficacy of HIFU2 was superior to that of the prototype HIFU1.

Aged↗
PubMed1998

Results of transrectal ultrasound-guided biopsies and clinical significance of Japanese prostate cancer.

BACKGROUND: We review the outcomes of ultrasound-guided biopsy in consecutive patients and assess clinical significance of Japanese prostate cancer. METHODS: Examination was made of 1469 patients subsequent to transrectal ultrasound-guided biopsy of the prostate gland. For 84 patients, two or more sets of ultrasound-guided biopsies were conducted following the initial negative results during this period. Two hundred and thirty-two patients with benign histology at the initial biopsy underwent transurethral resection of the prostate (TURP). The clinical significance of the cancers was assessed based on patient age and calculated tumor volume at diagnosis, assumed cancer volume doubling time and life-expectancy in the Japanese male population. RESULTS: Overall, 327 of the 1469 patients (22.3%) had prostate carcinoma. Positive biopsy rates in patients with PSA 2.0 ng/ml or lower, 2.1-4.0 ng/ml, 4.1-10.0 ng/ml and 10.1 ng/ml or greater were 4.6%, 8.6%, 15.8% and 59.5%, respectively. Of the 232 patients who underwent TURP, 15 (6.5%) had cancer. Of the 84 patients subjected to the multiple sets of biopsies, 19 (22.6%) cancers were detected. Of the 203 cancers without distant metastasis at initial biopsy, 13.3%, 25.1%, 32.5% and 40.4% of tumors for 2-, 3-, 4- and 6-year tumor doubling times gave no indication of clinical significance. Nearly half these patients (43-52%) had clinical stage T1c disease. The estimated proportion of clinically insignificant tumors in repeat biopsy was virtually the same as first set biopsies. CONCLUSIONS: Low PSA was not necessarily an indication of indolent cancer and repeat biopsy did not often demonstrate clinically unimportant cancers. Many patients with stage T1c disease may eventually prove to require no treatment.

Adult↗
PubMed1998

Magnetic resonance imaging of acute cerebellar ataxia: report of a case with gadolinium enhancement and review of the literature.

A 10-year-old girl exhibited severe cerebellar ataxia following acute enterocolitis, and was diagnosed as having acute cerebellar ataxia (ACA). MRI of the brain in the acute stage revealed moderate swelling of the cerebellum and abnormal signal intensity enhanced with gadolinium in the cerebellar hemisphere. This is the first report of an ACA case with positive gadolinium enhancement. Cases of ACA with MRI abnormalities are reviewed and the clinical entity of ACA is discussed in association with autoimmune encephalitis.

Acute Disease↗
PubMed1998

Pathophysiology of clinical varicoceles in infertile men.

In infertile men, clinical varicoceles most often occur bilaterally. In our experience with these patients, both testicles are smaller than normal. We find more than 25% to 35% immature and tapered sperm in in the ejaculum of these men, and the motility of the sperm is usually low. We have found serotonin in the plasma of the varicoceles, and believe this biogenic amine is responsible for the poor sperm motility. We now agree that a subset of neuroendocrine cells in the prostate secrete serotonin. Bilateral varicocele surgery can improve the patient's fertility potential, and we advocate surgical treatment.

Humans↗
PubMed1998

[Mutation of p53 gene and genomic instability in testicular tumors].

BACKGROUND: During the past decade, studies of human cancer have begun to yield molecular information on the identify of the multiple genetic changes in the development and progression of tumorigenesis. We investigated alterations of p53 and genomic instability in testicular tumors. MATERIALS AND METHODS: Polymerase chain reaction (PCR) single-strand conformation polymorphism was performed for analysis from exons 5 to 8 of p53 gene in 22 cases and PCR-microsatellite instability analysis using 8 microsatellite markers were conducted in 19 cases of testicular tumor. RESULTS: No mutations were noted for exons 5 to 8 of the p53 gene. Differences in unrelated microsatellites for tumor and corresponding normal DNA were detected in 5 of 19 (26.3%) cases examined. Alterations noted in more than 2 microsatellites were observed in 3 of 19 (15.8%) and categorized as replication error (RER) phenotype. Two of 7 (28.6%) seminomatous and 1 of 12 (8.3%) non-seminomatous testicular tumors patients showed RER. Two of 16 (12.5%) stage T1-3N0M0 and 1 of 3 (33.3%) stage T1-3N1-3M0-1 showed RER. CONCLUSIONS: Alterations in microsatellite instability may be involved in the development of testicular tumor.

DNA Replication↗
PubMed1998

Receptors for BPH growth factors are located in some neuroendocrine cells.

BACKGROUND: Prostatic neuroendocrine (NE) cells play an important role in the growth and differentiation of the prostate. We are still unable to characterize the exact mechanisms which lead to interactions between the epithelial cell and the NE cell. We offer several interactions generated by the NE cells, and speculate on some actions of selected NE cells. METHODS: We used thin sections of prostatic tissue made from 20 radical prostatectomies. Our team used validated rabbit polyclonal antibodies which were raised against human EGFR and C-erb B-2, using the streptavidin-peroxidase conjugate method. RESULTS: A strong immunoreactivity was noted with both antibodies in the cytosol of some NE cells. These cells had a dendritic appearance, and they were located in the acini and ducts of small-to-moderate-sized prostatic glands. Double immunostaining revealed the colocalization of both antigens with chromogranin A (CgA), a polypeptide that is expressed by NE cells. Of interest was the finding that EGFR and C-erb B-2 were colocalized as well as independently expressed by separate populations of NE cells. CONCLUSIONS: We conclude that NE cells may be regulated by the HER protein family, probably in a ligand-specific fashion. This is a revised report which identifies a pathway regulating NE cells, and their interactions with epithelial cells.

Animals↗
PubMed1997

Synthesis and cytotoxic studies of 5-O-(beta-glucopyranosyl)-2-nitrobenzyl caged L-leucyl-L-leucine methyl ester with increased solubility in PBS containing 1% DMSO.

We report the synthesis of a new type of a caged L-leucyl-L-leucine methyl ester, a sugar derivative 2, and study its photochemical and immunological properties. Compared with those of the previously reported o-nitrobenzyl caged compound, 1, and another new 4, 5-dimethoxy-2-nitorobenzyl caged compound 3, 2 was found to be almost 30 times more soluble in PBS containing 1% DMSO, and released leucyl-leucine methyl ester upon irradiation more efficiently than 1. Efficiency of induction of apoptosis of HL60 cells by irradiation of a solution containing 2 was only slightly lower than that by leucyl-leucine methyl ester itself.

Carbamates↗
PubMed1997

Characterization of a deletion mutation involving exons 3-7 of the WASP gene detected in a patient with Wiskott-Aldrich syndrome.

A case of Wiskott-Aldrich syndrome (WAS) suspected to have a deletion mutation in the WAS protein (WASP) gene had previously been reported (Ariga et al., 1997). Genomic polymerase chain reaction (PCR) suggested that exons 3-7 of the WASP gene were included in the deletion. Present Southern blot studies confirm that the deletion is approximately 2.0 kb in length, involving exons 3-7 and seemed to have been created by the fusion of introns 2 and 7. To characterize the deletion mutation in detail, we analyzed the PCR-amplified fragments of introns 2 and 7 from normal individuals and the fragment suspected of including the deletion junction from the patient. Sequencing of the patient fragment revealed that the deletion mutation involving exons 3-7 of the WASP gene did, indeed, result from the fusion of introns 2 and 7.

Base Sequence↗
PubMed1997

Studies on cytomegalovirus and Epstein-Barr virus infection in moyamoya disease.

In this study, measurement of Epstein-Barr virus (EBV) and cytomegalovirus (CMV) viral antibody titers and analysis of both viral genomic sequences using polymerase chain reaction (PCR) were performed to clarify the correlation of viral infection and Moyamoya disease. Serum samples were obtained from 64 patients with Moyamoya disease. The ages ranged from 5 to 66 years, with a mean age of 35.1 years. There were 23 males and 41 females. The serum antibody titers to CMV and EBV were measured by means of compliment fixation test and fluorescent antibody method respectively. Those titers of the patients were compared with those of 13 patients of atherosclerotic internal carotid occlusion and 34 normal volunteers. On the other hand, CMV and EBV genomic sequence using PCR, which was utilized with specific primer pairs, were performed in 22 patients of Moyamoya disease and ten normal volunteers. The following results were obtained; The antibody titer of EBV in Moyamoya disease was significantly higher than that in controls. However, no significant difference of antibody titer against CMV was detected. In EBV DNA analysis by use of PCR, EBV DNA was proved in 15 out of 20 patients with Moyamoya disease and four out of nine normal controls. Namely, EBV DNA was seen more frequently in patients with Moyamoya disease, compared with normal controls. In inverse, CMV DNA was not seen in patients with Moyamoya disease nor normal controls. In conclusion, the antibody titer of EBV revealed high levels in Moyamoya disease and EBV DNA was also detected more frequently in patients with Moyamoya disease. These results suggested a possibility that EBV infection might be involved in the pathogenesis of Moyamoya disease.

Adolescent↗
PubMed1997

Urinary continence following radical prostatectomy.

An examination was made of pre- and postoperative variables for predicting urinary continence following radical prostatectomy in 94 consecutive patients. Postoperative recovery of urinary continence continued for up to 18 months, when it plateaued. No pads were required in 73.0% of the patients at 18 months. The interval until recovery of urinary continence following surgery averaged 4.0 +/- 3.3 months. Clinical stage, pathologic stage, tumor grade, tumor volume, preservation of neurovascular bundles, methods of bladder neck reconstruction, internal urethrotomy for anastomotic stricture and postoperative adjuvant external beam radiation therapy provided no indication of postoperative urinary incontinence. Preoperative endocrine therapy, preoperative prostate-specific antigen level of > or = 10.0 ng/ml and age < 70 years at the time of surgery were all associated with a greater probability of urinary incontinence. Multiple factors are involved in the etiology of postprostatectomy urinary incontinence. In patients who had undergone surgery because of local progression following endocrine therapy associated with a high serum prostate-specific antigen level, a significantly inferior outcome was noted. Stricter criteria for indicating radical prostatectomy in patients with prostate cancer are needed. Surgical techniques should also be improved for better overall continence.

Adult↗
PubMed1997

Impact of life expectancy and tumor doubling time on the clinical significance of prostate cancer in Japan.

Theoretical projected prostate cancer volume at the time of expected death was determined based on patient age and index cancer volume at diagnosis, assumed cancer volume doubling time and life expectancy of the Japanese male population. Based on the data obtained, evaluation was made of the results for 104 consecutive radical prostatectomy cases with no prior treatment. Clinically insignificant cancer in 104 prostatectomy specimens was found to occur at 4.8, 10.6, 15.4 and 26.9% for tumor doubling times of 2, 3, 4 and 6 years, respectively. Assuming a 2-year doubling time with clinically insignificant cancer excluded, only 36.4% of significant cancers could be considered potentially curable and with a 3-year doubling time, 32.3%. For 4- and 6-year doubling times, only 30.7 and 25.0% of the clinically insignificant cancers were potentially curable, respectively. Approximately half of these insignificant cancers were clinically stage T1c disease. In all stage T1c cases, 8.8-47.1% was considered insignificant, depending on tumor doubling time. Patient life expectancy and tumor doubling time significantly determine the outcome of treatment for prostate cancer, especially in elderly males with higher risk of mortality. The outcome of radical prostatectomy is less satisfactory with these factors taken into consideration. Many patients with stage T1c disease may eventually prove to require no treatment.

Aged↗
PubMed1997

Panhypopituitarism due to Rathke's cleft cyst associated with pituitary oncocytoma.

A 38-year-old male with panhypopituitarism due to Rathke's cleft cyst associated with a pituitary oncocytoma is reported. The presenting signs were general myalgia and slight fatigue. Endocrine examinations revealed panhypopituitarism. Magnetic resonance imaging disclosed a suprasellar cystic lesion of the pituitary gland. Cytological examination demonstrated ciliated cells in the mucinous fluid flowing from the cyst during the pituitary operation. A pituitary oncocytoma with randomly scattered S-100 immunoreactive cells was found upon histologic examination of the nodular tissue curettaged from the internal wall of the cyst. These results suggest that the pituitary adenoma was derived from folliculostellate cells included in the Rathke's cleft wall.

Adenoma, Oxyphilic↗