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N Moriyama

Publications and source records attributed to N Moriyama.

At least 73 records · Page 4Linked to original sources
PubMed1999

Distribution of alpha1-adrenoceptor subtype mRNAs in human renal cortex.

OBJECTIVE: To determine the quantity and distribution of alpha1-adrenoceptor subtype mRNAs in human renal cortex. MATERIALS AND METHODS: Specimens of renal cortex tissue were obtained at the time of radical nephrectomy or total nephroureterectomy from 46 patients (mean age 59.0 years, sd 14.7) with renal cell carcinoma, renal pelvic or ureteric tumour. Using the reverse-transcriptase polymerase chain reaction (RT-PCR), the RNase protection assay and in situ hybridization, the presentation, quantity and distribution of alpha1-adrenoceptor subtype mRNAs were determined. RESULTS: Expression of the three alpha1-adrenoceptor subtype mRNAs (alpha1a, alpha1b and alpha1d) was confirmed in the arteries of the renal cortex (arciform, interlobular, arteriole), but among the three subtypes, the alpha1b was less apparent by in situ hybridization. Intense alpha1-mRNA staining was apparent especially in the smooth muscle of arterial walls. In both proximal and distal renal tubules, each of the alpha1-mRNAs was less marked in cytoplasm than in the arteries. In the glomeruli weak staining was detected in the endothelium but there was no obvious staining in the veins. RT-PCR showed all three subtypes of alpha1-adrenoceptor. The RNase protection assay showed that the predominant alpha1-adrenoceptor subtype mRNA in human renal cortex was alpha1a. However, the abundance of alpha1a-mRNA in human kidney was much less than in the prostate. CONCLUSION: Three alpha1-adrenoceptor subtype mRNAs were recognized in human renal cortex and detected particularly in the smooth muscle of the arteries. There was more alpha1a-adrenoceptor subtype in human renal cortex than the other subtypes. It is not known how each subtype operates against adrenergic stimulation; further studies are needed to examine receptor density or receptor function.

Adult↗
PubMed1999

Alveolar architecture of clear cell renal carcinomas (< or = 5.0 cm) show high attenuation on dynamic CT scanning.

BACKGROUND: To establish the correlation between tumor appearance on CT and tumor histology in renal cell carcinomas. METHODS: The density and attenuation patterns of 96 renal cell carcinomas, each < or = 5 cm in greatest diameter, were studied by non-enhanced CT and early and late after bolus injection of contrast medium using dynamic CT. The density and attenuation patterns and pathological maps of each tumor were individually correlated. RESULTS: High attenuated areas were present in 72 of the 96 tumors on early enhanced dynamic CT scanning. All 72 high attenuated areas were of the clear cell renal cell carcinoma and had alveolar architecture. The remaining 24 tumors that did not demonstrate high attenuated foci on early enhanced scanning included three clear cell, nine granular cell, six papillary, five chromophobe and one collecting duct type. With respect to tumor architecture, all clear cell tumors of alveolar architecture demonstrated high attenuation on early enhanced scanning. CONCLUSION: Clear cell renal cell carcinomas of alveolar architecture show high attenuation on early enhanced dynamic CT scanning. A larger number of patients are indispensable to obtaining clear results. However, these findings seem to be an important clue to the diagnosis of renal cell carcinomas as having an alveolar structure.

Carcinoma, Renal Cell↗
PubMed1999

Clinical significance of magnetic resonance cholangiopancreatography for the diagnosis of cystic tumor of the pancreas compared with endoscopic retrograde cholangiopancreatography and computed tomography.

BACKGROUND: Cystic tumor of the pancreas has been investigated by a variety of imaging techniques. Magnetic resonance cholangiopancreatography (MRCP) is being widely used as a non-invasive diagnostic modality for investigation of the biliary tree and pancreatic duct system. The purpose of this study was to compare MRCP images with those of endoscopic retrograde cholangiopancreatography (ERCP) and computed tomography (CT) in order to clarify the diagnostic efficacy of MRCP for cystic tumor of the pancreas. METHODS: We retrospectively studied 15 patients with cystic tumor of the pancreas that had been surgically resected and histopathologically confirmed. There were five cases of intraductal papillary adenocarcinoma, five of intraductal papillary adenoma, two of serous cyst adenoma, two of retention cyst associated with invasive ductal adenocarcinoma and one of solid cystic tumor. RESULTS: In all cases MRCP correctly identified the main pancreatic duct (MPD) and showed the entire cystic tumor and the communication between the tumor and the MPD. On the other hand, the detection rate by ERCP of the cystic tumor and the communication between the cystic tumor and the MPD was only 60%. Although the detection rates by CT for the septum and solid components inside the cystic tumor were 100 and 90.0%, respectively, those of MRCP for each were 58.3 and 20.0%. CONCLUSION: MRCP is capable of providing diagnostic information superior to ERCP for the diagnosis of cystic tumor of the pancreas. Although MRCP may provide complementary information about the whole lesion of interest, the characteristic internal features of cystic tumor of the pancrease should be carefully diagnosed in combination with CT.

Adenocarcinoma↗
PubMed1999

Computer-aided diagnosis in full digital mammography.

RATIONALE AND OBJECTIVES: The authors clarify the detection rates for breast cancerous tumors and clustered microcalcifications with computer-aided diagnosis (CAD) based on Fuji Computed Radiography. The authors also determine whether mammographic reading with CAD contributes to the discovery of breast cancer. METHODS: Data acquired by Fuji Computed Radiography 9000, which consisted of 4148 digital mammograms including 267 cases of breast cancer, was transferred directly to an analysis workstation where an original software program determined extraction rates for breast tumors and clustered microcalcifications. Furthermore, using another 344 mammograms from 86 women, observer performance studies were conducted on five doctors for receiver operating characteristic (ROC) analysis. RESULTS: Sensitivity to breast cancerous tumors and clustered microcalcifications were 89.9% and 92.8%, respectively false-positive rates were 1.35 and 0.40 per image, respectively. The observer performance studies indicate that an average Az value for the five doctors was greater with the CAD system than with a film-only reading without CAD, and that a reading with CAD was significantly superior at P < 0.022. CONCLUSIONS: It has been shown that CAD based on Fuji Computed Radiography offers good detection rates for both breast cancerous tumors and clustered microcalcifications, and that the reading of mammograms with this CAD system would provide potential improvement in diagnostic accuracy for breast cancer.

Breast Neoplasms↗
PubMed1999

Optimal injection protocol for CT evaluation during hepatic arterial infusion chemotherapy.

OBJECTIVE: As an imaging modality for follow-up during continuous or repeated hepatic arterial infusion chemotherapy using a hepatic intra-arterial indwelling catheter, the usefulness of CT while infusing contrast through the indwelling catheter (reservoir port) was examined. METHODS: Using reservoir ports implanted in eight patients with hepatic metastasis from colon cancer, radioisotope perfusion scintigraphy (RI), CT (three rates of infusion of contrast were used), and digital subtraction angiography (AG) were performed to compare the modalities' ability to visualize the intrahepatic and abnormal extrahepatic distributions. RESULTS: CT (infusion rate 0.1 mL/sec) was superior to AG and RI in terms of the ability to visualize intrahepatic distribution, particularly in small areas, and facilitated 3D delineation of the distribution. In evaluating extrahepatic distribution, CT also outperformed the other modalities. CONCLUSIONS: For imaging study follow-up during hepatic arterial infusion chemotherapy, CT proved to be more useful than conventional RI and AG.

Aged↗
PubMed1999

Detection failures in spiral CT screening for lung cancer: analysis of CT findings.

PURPOSE: To clarify the computed tomographic (CT) findings and the progression of minute lung cancers that were missed at initial spiral CT screening but were later detected. MATERIALS AND METHODS: The findings from seven patients with lung cancer that was missed at the initial spiral CT screening were reviewed. Retrospective CT findings, time to detection, cell type, and pathologic stage were evaluated. RESULTS: Minute lung cancers missed at early spiral CT included a nodule among the shadows of old tuberculosis (n = 2), a faint nodule with high attenuation in the center of the nodule (n = 1), an increase in attenuation just adjacent to an axial peripheral pulmonary vessel (n = 1) and adjacent to a craniocaudal peripheral pulmonary vessel (n = 1), and a minute faint nodule (n = 2). The time to detection ranged from 6 to 18 months. At pathologic examination, six cancers were stage I, and one was stage II. CONCLUSION: Minute nodules of lung cancer that are near the threshold of detectability may be missed at spiral CT screening. It is important to examine noncalcified nodules with thin-section CT even when lesions from prior disease, such as those from old tuberculosis, exist and to evaluate the shadows of pulmonary vessels carefully. A follow-up examination is highly recommended.

Adenocarcinoma↗
PubMed1999

New alpha1-adrenoceptor antagonist, JTH-601, shows more than 10 times higher affinity for human prostates than arteries.

PURPOSE: We compared the affinities of a new alpha1-adrenoceptor (AR) antagonist, JTH-601 with those of several alpha1-AR antagonists in human prostates and arteries. RESULTS: In the functional study, noradrenaline produced concentration-dependent contractions in human prostates and mesenteric arteries. The pA2/pKB values for the antagonists in the human prostate were 9.78 for tamsulosin, 8.84 for JTH-601, 8.39 for WB4101, 8.23 for prazosin, 8.12 for JTH-601-G1 (a main metabolite of JTH-601 in human) and 6.57 for BMY7378. Compared these affinities with those in the mesenteric artery, only JTH-601 and JTH-601-G1 exhibited unique uroselectivity, showing 10- to 20-fold higher affinity for the human prostate than for mesenteric artery. The affinity profile of these antagonists suggested that the noradrenaline-induced contractions in the human prostate and the mesenteric artery were mediated by the alpha1L-AR and alpha1B-AR, respectively. In the competition binding study, the pharmacological profiles of the antagonists against [3H]-prazosin were examined in the human prostate and aorta. The resulting pKi values for JTH-601 and JTH-601-G1 were also approximately 10- to 20-fold higher for the human prostate than for the human aorta. CONCLUSION: These results have suggested that JTH-601 and JTH-601-G1 are unique uroselective alpha1-AR antagonists that show higher affinity for the human prostate than for the human arteries.

Adrenergic alpha-Antagonists↗
PubMed1999

Evidence for predominant mediation of alpha1-adrenoceptor in the tonus of entire urethra of women.

PURPOSE: We separated the entire length of the isolated human female urethra into seven parts from external urethral meatus to bladder neck and examined regional differences in contractile responses to noradrenaline, clonidine, acetylcholine and KCl. MATERIALS AND METHODS: The entire urethra was obtained from 9 female patients with a mean age of 72.2 +/- 1.8 years. The entire urethra (35 to 42 mm. in length) was transversely cut into seven parts, and the contractile responses to noradrenaline, clonidine, acetylcholine and KCl of these parts were examined. RESULTS: Noradrenaline but not clonidine produced concentration-dependent contraction in all parts, with a peak amplitude in middle to proximal urethra. In contrast, acetylcholine produced contraction only in proximal urethra and bladder neck. The amplitudes of noradrenaline-induced contraction were normalized against those induced by KCl, revealing similarity in patterns between noradrenaline-induced contractions and urethral pressure profile in human female urethra. These contractions to noradrenaline and acetylcholine were competitively inhibited by prazosin (pK(B): 8.38 +/- 0.10) and atropine (pK(B): 8.52 +/- 0.43), respectively. CONCLUSION: These findings suggest that sympathetic innervation helps maintain resting urethral tonus, mainly through alpha1-adrenoceptors.

Acetylcholine↗
PubMed1999

[Quality of life in patients with testicular cancer after high orchiectomy, radiation therapy or chemotherapy].

We evaluated the physical or psychosocial states of testicular cancer patients receiving orchiectomy, radiation therapy and chemotherapy to assess their quality of life during and after treatment. The subjects were 33 post-treatment patients with testicular cancer who responded to the questionnaire we mailed to them. The quality of life score during chemotherapy showed a decrease, which was accompanied by gastrointestinal symptoms induced by anti-cancer drugs. With regard to the difference in adjuvant treatment types, the surveillance group showed the highest score in the satisfaction of daily life. Moreover, married patients tended to be satisfied with daily life more than non-married patients. With regard to sexual or erectile function, scores of testicular cancer patients, especially in the retroperitoneal lymph node dissection group, were inferior to these of normal volunteers. In conclusion, the physical or psychosocial states after treatment for testicular cancer depend not only on treatment type but also marriage status.

Adult↗
PubMed1998

Primary sclerosing pancreatitis and cholangitis.

CONCLUSION: The clinical course of our patient suggests the association between chronic pancreatitis and primary sclerosing cholangitis (PSC), as well as the usefulness of prednisolone for the treatment of this condition. BACKGROUND: Although alterations in the pancreatic duct have been reported, the association between chronic pancreatitis and PSC remains uncertain. METHODS AND RESULTS: A long-term follow-up case of chronic pancreatitis accompanied by PSC is presented. A 58-yr-old man complaining of epigastric distress was admitted to our hospital in July 1990. Endoscopic retrograde cholangio-pancreatography (ERCP) showed a stricture of the distal common bile duct and a narrowing of the main pancreatic duct (MPD) with mild ectasia of its branches in the head of the pancreas. ERCP taken in June 1992 revealed localized narrowings in both the right and the left main hepatic ducts, and irregularity of the MPD through the entire pancreas. An ERCP taken in June 1996 showed a progression of the narrowings of the bile ducts. The patient was diagnosed as having chronic pancreatitis accompanied by PSC. ERCP revealed a remarkable improvement of the bile ducts after 4 wk of treatment with prednisolone.

Anti-Inflammatory Agents↗
PubMed1998

Co-expression of hepatocyte growth factor and its receptor in human prostate cancer.

Hepatocyte growth factor acts differently depending on the organs or tumours involved. It may be produced simultaneously with its receptor, c-Met, in several types of malignant tumour cells and may exercise an autocrine regulation. To analyse the effect of hepatocyte growth factor in human prostate cancer, we conducted immunohistochemistry, in situ hybridization and the reverse transcriptase polymerase chain reaction. The first two techniques revealed the growth factor in prostate cancer cells, and the polymerase chain reaction confirmed this expression. c-Met is expressed in prostate cancer cells, but not in interstitial cells. Hepatocyte growth factor is expressed in interstitial cells, especially in hormone-treated cancer tissue, indicating that the growth factor pathway changes with the hormonal status. Low-grade tumours expressed c-Met at the plasma membrane. Higher grade tumours tended to express it in the cytoplasm, suggesting that the role of c-Met as the hepatocyte growth factor receptor was blocked in higher grade tumours. The relationship between the growth factor and its receptor is thus influenced by hormonal status and differentiation in prostate cancer and is not explained simply in terms of autocrine or paracrine action.

Aged↗
PubMed1998

Quantification and distribution of alpha1-adrenoceptor subtype mRNAs in human proximal urethra.

1. We performed RNase protection assays and in situ hybridization to investigate the ratio of the three alpha1-adrenoceptor subtype mRNAs, alpha1a, alpha1b and alpha1d, in human proximal urethra, and their localization in urethral cross-sections. As revealed by the RNase protection assays, alpha1a was the predominant subtype mRNA in both male and female urethral samples. Alpha1d mRNA was detected only in the female sample, and alpha1b mRNA was not detected in any of the samples tested. The ratio of the abundance of the subtype mRNAs, alpha1a:alpha1b:alpha1d, was 100:0:0 in the male urethra and 90:0:10 in the female urethra. 2. In situ hybridization studies showed no significant differences in the cross-sectional distribution of alpha1-adrenoceptor subtype mRNAs between male and female urethras. Intense alpha1a staining was observed in the smooth muscle of the urethra, but alpha1b and alpha1d staining was much less intense. 3. Of the three cloned alpha1 subtypes, alpha1a is the most likely to be responsible for the contraction of the human urethra. Owing to the side effects of nonselective alpha1 drugs, alpha1-selective drugs may be clinically superior to nonselective drugs for the treatment of urethral disorders.

Aged↗
PubMed1998

Evaluation of histological structure and its effect on the distribution of alpha1-adrenoceptors in human benign prostatic hyperplasia.

OBJECTIVE: To evaluate the histological structure of benign prostatic hyperplasia (BPH) and its relationship with the density of alpha1-adrenoceptors in smooth muscle. MATERIALS AND METHODS: Specimens from hyperplastic tissues obtained from 14 patients with BPH were evaluated for the density of alpha1-adrenoceptors in smooth muscle using autoradiography, Mallory-Azan staining and computer-assisted image analyses. The binding of [3H] tamsulosin (a selective alpha1-blocker) and the ratio of smooth muscle area was calculated, and the density of alpha1-adrenoceptors per area of smooth muscle determined by dividing the degree of binding by the ratio of smooth muscle to total area. RESULTS: There was a significant difference between the ratio of smooth muscle area in the hyperplastic acinar nodule and the surrounding stroma (P < 0.01). The density of alpha1-adrenoceptor per smooth muscle area was significantly higher in the hyperplastic acinar nodule than in the surrounding stroma (P < 0.05). There was no correlation between prostatic weight and the ratio of smooth muscle area or the density of alpha1-adrenoceptors in each region. CONCLUSION: The distribution of alpha1-adrenoceptors on smooth muscle differed with histological structure; both the histological conformation and the difference in the distribution of alpha1-adrenoceptors could affect urethral obstruction in BPH.

Autoradiography↗
PubMed1998

Immunohistochemical study of Fas, Fas ligand and interleukin-1 beta converting enzyme expression in human prostatic cancer.

OBJECTIVE: To determine the cellular expression of Fas, Fas ligand and interleukin-1 beta converting enzyme (ICE) in prostatic cancer. PATIENTS AND METHODS: Specimens of prostate were obtained from 21 patients (mean age 66 years, SD 5) undergoing radical prostatectomy for prostatic cancer. Nine of the 21 patients had received endocrine therapy before surgery. Specimens were also obtained from 10 patients with benign prostatic hypertrophy (BPH) and during autopsy from 10 patients who had died from hormone-unresponsive prostate cancer. Paraffin-embedded sections were cut from the specimens and stained immunohistochemically to detect Fas, Fas ligand and ICE. RESULTS: Fas was expressed in all 21 of the cancer specimens while Fas ligand was detected in none and ICE was expressed in 11. The difference between the expression of Fas and ICE was significant (P < 0.001). ICE was expressed in nine of 12 patients who were untreated before surgery and in two of nine treated with endocrine therapy (P < 0.05). Fas expression was detected in the specimens from all 10 patients with BPH and in all 10 autopsy specimens; the expression, tended to be more marked than that in specimens from total prostatectomy (P < 0.1). CONCLUSION: The expression of ICE was weaker than that of Fas in the total prostatectomy specimens, suggesting a possible interruption of the apoptotic signalling pathway. Prostates with BPH and hormone-unresponsive cancer therefore showed no appreciable change in Fas expression when compared with total prostatectomy samples.

Aged↗
PubMed1998

The alpha1L-adrenoceptor subtype in the lower urinary tract: a comparison of human urethra and prostate.

OBJECTIVE: To identify the alpha1-adrenoceptor subtypes present in the human urethra, by comparing the affinity of prazosin for alpha1-adrenoceptors in the rabbit, dog and human prostatic urethra, and in the dog and human prostate. MATERIALS AND METHODS: The study comprised samples of human prostate and prostatic urethra, obtained by open prostatectomy of patients with benign prostatic hyperplasia, and of the proximal urethra and prostate from male Beagle dogs and rabbits. Specimens were homogenized, filtered and pelleted by centrifugation. Nonspecific binding was determined in the presence of 1 mmol/L prazosin when assessing [3H]YM-617 (tamsulosin) binding, and 10 mmol/L phentolamine when assessing [3H]prazosin binding. Specific binding was defined as the difference between total binding and nonspecific binding. RESULTS: The dissociation constant for [3H]prazosin in the human prostate (0.088 nmol/L) was less than that in the rabbit urethra (0.299 nmol/L), dog urethra (0.604 nmol/L), dog prostate (0.482 nmol/L) and human urethra (0.254 nmol/L). The affinity of prazosin was also investigated by determining the potency of the inhibition of [3H]YM-617 binding. The affinity of prazosin for alpha1-adrenoceptors in the human urethra (Ki, 2.5 nmol/L) was lower than its affinity for alpha1-adrenoceptors in the human prostate (Ki, 0.25 nmol/L) and all of the cloned subtypes (Ki, 0.26-0.44 nmol/L). CONCLUSION: The alpha1L-adrenoceptor subtype is more prominent in the human, rabbit and dog urethra and dog prostate than in the human prostate.

Adrenergic alpha-Antagonists↗
PubMed1998

Usefulness of magnetic resonance imaging with dynamic contrast enhancement and fat suppression in detecting a pancreatic tumor.

The purpose of this study was to compare the value of dynamic magnetic resonance imaging (MRI) and fat suppression in detecting a pancreatic tumor. The subjects were 19 patients with invasive ductal adenocarcinoma and six patients with islet cell tumor where diagnosis was established pathologically. Breath-hold gradient echo images, breath-hold gradient echo images with fat suppression and breath-hold gradient echo images with dynamic enhancement at 1.5 T were obtained for all patients. The efficacies of these three imaging techniques were compared by calculating the contrast-to-noise ratio, as indicative of conspicuousness between a tumor-affected and a normal pancreas. As for adenocarcinoma, our results indicated that the usefulness in detecting the tumor was high, decreasing in the order dynamic contrast images > fat suppression images > plain images, and that the difference between any two of these three types of image was statistically significant. On the other hand, these imaging techniques showed no statistically significant difference in detecting islet cell tumors. In conclusion, dynamic MRI is the best method for detecting pancreatic adenocarcinoma. As the fat suppression technique has the advantage of being non-invasive, this method is suitable for screening studies of pancreatic adenocarcinoma. However, no advantage was recognized in using the fat suppression technique for detecting an islet cell tumor in comparison with plain MRI.

Adipose Tissue↗