Biomedical subjects

M Akimoto

Publications and source records attributed to M Akimoto.

At least 37 records · Page 2Linked to original sources

PubMed2001

The short-term effects of terazosin in Japanese men with benign prostatic hyperplasia.

We evaluated the short-term efficacy of terazosin for treating symptomatic benign prostatic hyperplasia (BPH). Thirty men, aged 52 to 83 years (mean: 69.2 years) complaining of obstructive urinary symptoms due to BPH who had not received any prior treatment for their symptoms were orally administered 2 mg/day of terazosin. Symptoms (the total IPSS and the obstructive and irritative symptom scores) and objective parameters (peak flow rate [Qmax] and prostatic volume) were evaluated before treatment and after 1, 2, and 4 weeks of treatment. The mean total IPSS and the mean symptom scores for weak stream and nocturia were significantly decreased after only 1 week of treatment, while the mean scores for emptying, frequency, and urgency were significantly decreased after 2 weeks of treatment. However, the mean scores for intermittency and hesitancy did not decrease significantly at any time during treatment. Regarding objective parameters, the mean Qmax was significantly improved after 1 week of treatment, but the mean prostatic volume remained almost unchanged after 4 weeks. In conclusion, short-term terazosin therapy not only improved Qmax but also alleviated symptoms including irritative symptoms.

Adrenergic alpha-Antagonists↗

PubMed2001

Duodenal somatostatinoma and erythrocytosis in a patient with von Hippel-Lindau disease type 2A.

A female with von Hippel-Lindau (VHL) disease type 2A first presented with erythrocytosis at the age of 9 years. This patient revealed multiple paragangliomas at age 22. After the removal of tumors, a retinal hemangioblastoma developed. Our diagnosis of VHL disease type 2A was confirmed. Moreover, systemic examination showed a duodenal somatostatinoma. Frequent and long-term monitoring is important for patients with pheochromocytomas or paragangliomas, and a screening for VHL disease and other hereditary cancer syndromes is recommended. Recognition of neuroendocrine tumors as a manifestation of VHL disease permits earlier diagnosis and improves prognosis.

Adult↗

PubMed2001

Content analysis of group work sessions in the context of an educational program for inpatient diabetes patients.

This study investigated the changes in emotions and attitudes of diabetic patients as observed in group work sessions linked to an inpatient diabetic educational program. Using content analysis of transcripts from Sessions 1 and 3 of 8 selected groups (40 patients), in Session 1 negative emotions or attitudes such as anxiety, remorse, or self-blame, a lack of understanding of diabetes, along with a willingness to undertake self-care were frequently expressed. In Session 3, more positive emotions and attitudes towards self-care (willingness, specific plans, and resolutions), satisfaction, and relief or hope were frequently expressed. These results suggest that the patients participating in the group work sessions moved toward adaptation to diabetes, although the effects of the group work were not separated from those of the inpatient educational program.

Adaptation, Psychological↗

PubMed2001

[Usefulness of power Doppler ultrasound in a patient with renal cell carcinoma in the wall of a simple renal cyst].

We present a case of renal cell carcinoma in the wall of a simple renal cyst. A 54-year-old man visited our hospital with a complaint of right back pain. Ultrasound study revealed right hydronephrosis, a ureteral stone, and a 9 x 8 cm renal cyst, with a tumor, 2 cm in diameter, in the cyst wall. Power Doppler Ultrasound and enhanced computed tomography demonstrated hypervascularity of the tumor. Clinically, he was diagnosed as renal cell carcinoma and nephrectomy was performed. Pathological findings of the tumor showed clear cell carcinoma in the wall of a simple renal cyst. Twelve months after the nephrectomy, he was free from recurrence.

Carcinoma, Renal Cell↗

PubMed2001

Impaired blood rheology by remnant-like lipoprotein particles: studies in patients with fatty liver disease.

Fatty liver disease (FLD) characterised by a high plasma levels of lipoproteins and remnant-like lipoproteins (RLP) is a risk factor for impaired microvascular blood flow, endothelial cell dysfunction and atherosclerosis. Using an immunoseparation technique with a gel mixture containing human monoclonal antibodies to apo A-I and apo B-100, we separated and measured RLP cholesterol (RLP-C) levels which reflect RLP in patients with FLD (n=20). Whole blood transit time (TT) was determined by a microchannel method (MC-FAN) which allows blood flow to be viewed via a microscope connected to an image display unit. RLP-C levels were higher (P<0.01) in FLD, 15.6 +/- 1.0 mg/dl compared with 4.8 +/- 0.5 mg/dl for controls (n=20). Similarly, TT was longer (P<0.01) in FLD, 284.5 +/- 26.1 sec/100 microl compared with 82.8 +/- 1.0 sec/100 microl for controls. Since the liver is a major site for RLP formation and degradation, it is affected to a greater extent in patients with FLD. It is likely that high levels of RLP can impair microvascular perfusion in the liver tissue and contribute to the development and progression of FLD.

2-Chloroadenosine↗

PubMed2001

[Evaluation of endoscopic papillary balloon dilation (EPBD) using one-step catheter for removal of common bile duct stones].

We compared the results of EPBD in 18 patients using one-step catheter (one-step group) with those in 46 patients using usual two-step catheter (two-step group). The frequency of endoscopy and bile duct clearance were the equal in both groups. Pancreatitis occurred in only one patient of two-step group. Elevations of the amylase values were the equal in both groups. Amylase values after EPBD tended to decrease in 11 patients whose amylase values were above 500 IU/l before EPBD. Using one-step catheter in EPBD was useful for removing common bile duct stones easily and safety.

Aged↗

PubMed2000

High-frequency endoluminal ultrasonography for staging transitional cell carcinoma of the bladder.

OBJECTIVES: To assess the feasibility and limitations of endoluminal ultrasound (ELUS) for clinical staging of bladder tumors. METHODS: From 1998 to 1999, 32 patients with transitional cell carcinoma of the bladder were evaluated by high-frequency ELUS using miniature ultrasound transducers (20 MHz, 5.1F or 7.2F) before transurethral resection. Clinical staging using ELUS was compared with the results of pathologic staging. RESULTS: Seventeen (94%) of the 18 patients with superficial tumors on ELUS were confirmed by pathologic examination to have Stage pTa (n = 12) or Stage pT1 (n = 5) disease, and 11 (63%) of the 14 patients with muscle-invasive tumors on ELUS were confirmed by pathologic evaluation to have Stage pT2a (n = 2) or Stage pT2b (n = 9) disease. In all of the misdiagnosed patients, the tumor lacked a well-defined base and was larger than 2 cm in size. It was difficult to distinguish between Stage Ta and Stage T1 tumors because of the limited resolution of ELUS and between Stage T2a and Stage T2b tumors because of its low penetration. CONCLUSIONS: ELUS using a high-frequency (20 MHz), miniature ultrasound transducer is able to distinguish superficial tumors from those with muscle invasion. However, the lack of penetration of the sonographic beam places major limitations on the evaluation of the depth of the invasion in large (greater than 2 cm) tumors with a broad base.

Adult↗

PubMed2000

Adenovirus-mediated gene transfer of basic fibroblast growth factor promotes the survival of primary-cultured rat neuronal cells.

We constructed two replication-deficient recombinant adenovirus vectors coding human basic fibroblast growth factor (bFGF), one with and one without the interleukin-2 (IL-2) secretory signal sequence and examined their neurotrophic effects on primary neuronal cells in vitro. The primary neuronal cells were successfully infected at a high efficiency with the adenovirus vectors. bFGF protein was detected in the culture medium of the neurons infected with both these vectors. The cells infected with the bFGF-expressing adenovirus containing the IL-2 signal sequence showed 2- to 10-fold higher levels of secretion levels than cells infected with the native bFGF-expressing adenovirus alone. Both bFGF-expressing vectors augmented the survival of primary neuronal cells in an in vitro culture, compared with a mock infection or control virus infection. Notably, the cells infected with the bFGF-expressing adenovirus containing the IL-2 signal sequence were markedly enhanced cell survival in the early phase of the culture, compared with the control cells and even those infected with the bFGF-expressing adenovirus without the IL-2 signal sequence. However, in the late phase of neuronal culture, neither viral vector could support the cell survival. In contrast the co-infection of the bFGF-expressing vector with a Bcl-xL-expressing vector was extremely effective on neuronal survival.

Adenoviridae↗

PubMed2000

Role of antioxidant systems in human androgen-independent prostate cancer cells.

BACKGROUND: Most prostate cancer cells respond to initial hormonal therapy; however, some of them eventually acquire resistance to the hormonal therapy. Hormone-independent prostate cancer usually exhibits resistance to chemotherapy and radiotherapy. Antioxidant systems are known to be involved in the resistance of cancer cells to chemotherapy and radiotherapy. Therefore, it is of significance to examine antioxidant systems of hormone-independent prostate cancer for enhancing the efficacy of cancer therapy. METHODS: Three cell lines of human hormone-independent prostate cancer (PC-3, PC-3 MA2, and HPC36M) were examined for activities of superoxide dismutase, catalase, and glutathione peroxidase, and for levels of protein and nonprotein thiols such as metallothionein, glutathione, and thioredoxin. Sensitivity of these cells to anticancer drugs and inducers of reactive oxygen species such as paraquat, tert-butylhydroperoxide, and hydrogen peroxide was determined by microtiter assay. RESULTS: PC-3 and PC-3 MA2, which were derived from bone metastases, were resistant to paraquat, hydrogen peroxide, and cisplatin compared with HPC36M, which was obtained from the primary prostate cancer. However, HPC36M was resistant to vinblastine compared with PC-3 and PC-3 MA2. Both PC-3 and PC-3 MA2 had higher activities of catalase and glutathione peroxidase and higher levels of glutathione and metallothionein than HPC36M. CONCLUSIONS: These data suggest that enhanced ability in scavenging free radicals by antioxidant enzymes and thiol compounds may, at least in part, contribute to the resistance of bone metastatic prostate cancer during chemotherapy.

Androgens↗

PubMed2000

Modulation of telomerase activity by zinc in human prostatic and renal cancer cells.

Because the up-regulation of telomerase in most cancer tissues is considered to be responsible for the unlimited proliferation of cancer cells, suppression of telomerase activity is an attractive potential target for cancer therapy. The mechanism for the activation of telomerase in cancer cells, however, is still unclear. In the present study, we demonstrated that Zn induces an enhancement of telomerase activity in the human renal cell carcinoma (NRC-12) and prostatic cancer (DU145) cell lines. The maximum elevation of the activity was observed 6 hr after treatment with 100 microM Zn; it was diminished by the addition of either metal chelator or cycloheximide. Other metals such as Cd and Cu also enhanced telomerase activity but to a lesser extent, and no correlation between the activation of telomerase and the induction of metallothionein was observed. Our findings provide the first evidence that metals, especially Zn, can modulate telomerase activity in cancer cells.

Cadmium↗

PubMed2000

Reciprocal effect of unsulfated and sulfated forms of cholecystokinin-octapeptide on gastric acid secretion in the rat.

The sulfated and unsulfated forms of cholecystokinin-octapeptide (CCK-8) were compared, with respect to their effect on gastric acid secretion, in the rat. Unsulfated CCK-8 stimulated acid secretion in a dose-dependent manner, while the sulfated form was without stimulatory effect; thus, sulfation of the tyrosine residue in the seventh position from the C terminus completely abolished the gastrin-like action of CCK-8. Compared with pentagastrin and human gastrin II, unsulfated CCK-8 gave lower calculated maximal response. While sulfated CCK-8 given alone had no effect on acid secretion, it caused marked inhibition of the plateau response to submaximal pentagastrin. This inhibition was surmountable with higher doses of pentagastrin, suggesting a competitive type of inhibition. It is, therefore, concluded that lack of sulfation of the tyrosine residue in the seventh position does not exclude CCK-8 from occupying the gastrin receptor; but does prevent the hormone-receptor interaction that leads to the secretory response. These observations in the rat are different from those in the dog where desulfation of tyrosine renders the CCK analog, caerulein, ineffective in its ability to stimulate acid secretion.

Animals↗

PubMed2000

Optical coherence tomograghy to confirm early closure of macular holes.

PURPOSE: To report that optical coherence tomography as early as 24 hours after macular hole surgery shows anatomic configuration of the closed macular holes. METHOD: In a prospective study, seven eyes of seven consecutive patients with stage 3 or 4 idiopathic macular hole underwent surgery. Optical coherence tomography was performed preoperatively and at 24, 48, and 72 hours after the surgery. RESULTS: Optical coherence tomography images could be obtained on four out of the seven eyes at 24 hours after surgery. These images showed anatomic configuration of the closed macular holes. Surgical success was confirmed in all of the eyes when the gas was completely absorbed. CONCLUSION: Optical coherence tomography revealed anatomic configuration of surgically closed macular holes within 24 hours after successful surgery.

Aged↗

PubMed2000

Gastric pH profiles of beagle dogs and their use as an alternative to human testing.

Gastric pH levels were measured in samples of gastric aspirates from eight fasted beagle dogs. The gastric pH in fasting dogs fluctuated from 2.7 to 8.3, with a mean of 6.8+/-0.2 (SE). Each dog received the following four treatments in randomly-assigned order: (A) distilled water; (B) a placebo capsule; (C) pentagastrin, and (D) ranitidine. The gastric pH remained relatively constant after distilled water administration. In contrast, the treatments with pentagastrin and placebo capsule each lowered gastric pH. Pretreatment with pentagastrin was more successful in lowering gastric pH than that with placebo capsule. On the other hand, the pH rose above 7.0 in all dogs by the first hour after treatment with ranitidine. This animal model may be helpful in evaluating the biopharmaceutics of drugs exhibiting pH-dependent dissolution or decomposition.

Animals↗

PubMed2000

Adenoviral gene transfer of basic fibroblast growth factor promotes angiogenesis in rat brain.

Cerebral ischemic disease often causes morbidity and mortality, while the induction of new blood vessels is expected to provide a therapeutic effect in this occlusive cerebrovascular disease. In this study, we utilized two replication-deficient adenoviral vectors containing cDNA from basic fibroblast growth factor (bFGF), a well-known angiogenic factor, and examined whether biological angiogenic activity of adenovirally gene-transferred bFGF could be observed in the rat brain. One vector contained native cDNA from bFGF without the secretory signal sequence and the other contained the same cDNA fused with an interleukin-2 secretory signal sequence. After ventricular administration of these viral vectors, gene-transferred cells demonstrated a high immunoreactivity against the anti-bFGF antibody and a remarkably high concentration of bFGF was detected in the cerebrospinal fluid. A semiquantitative analysis of angiogenic activity revealed that bFGF gene transfer induced angiogenesis in normal rat brains, with a more pronounced angiogenic effect seen with the vector of a secreted form than with the vector without a secretory signal sequence. These results suggest that bFGF gene transfer using these adenoviral vectors might be useful for the treatment of ischemic cerebrovascular disease.

Adenoviridae↗

PubMed2000

Renal masses detected by general health checkup.

BACKGROUND: A total of 60,604 persons underwent a general health checkup at Toma Hospital, Saitama, Japan, between January 1993 and June 1997, and transabdominal ultrasonography (US) was performed on all persons. We investigated the usefulness of transabdominal US in detecting renal tumors during general health checkups. METHODS: A definite diagnosis was made in cases where the re-examination by US revealed calculus with acoustic shadow or a simple cyst. Computed tomography (CT) was conducted in patients suspected of having a renal tumor, and a diagnosis of renal angiomyolipoma (AML) was made if plain CT gave evidence of a fatty component. Patients diagnosed as having a renal cell carcinoma (RCC) with non-uniform enhancement underwent nephrectomy. If a definite diagnosis could not be made even by contrast CT, the monitoring by US and contrast CT once a year was continued. RESULTS: Of 97 (0.16%) patients whose transabdominal US findings indicated a diagnosis of suspected renal tumor, 58 underwent the re-examination by US; of these, CT was conducted in 47. Detailed US revealed a hyperechoic pattern in 44 patients, a mixed pattern in nine and an isohypoechoic pattern with internal echo in five. By plain CT, 24 patients were diagnosed as having AML, and two as having renal calcification. Contrast CT enabled a diagnosis of renal cyst to be made in two patients and renal tumor in 14. All 14 patients with RCC except one underwent nephrectomy, which provided pathologic evidence supporting the diagnosis. Five patients had a tumor unidentifiable by CT, with continuing periodic follow-up by US and CT. Eleven patients underwent no CT. CONCLUSION: Of the 60,604 persons who underwent a general health checkup, we found 14 cases of RCC and 24 cases of AML. As a small RCC has a favorable prognosis, patients greatly benefit from early detection; therefore, we should recognize the importance of identifying renal masses by US screening during general health checkups.

Adolescent↗

PubMed2000

Changes in vasoactive substances during gastric ulcer healing.

In order to study the roles of vasoactive peptides during tissue repair of gastric ulcers, we compared concentrations in tissue surrounding gastric ulcers of endothelin-1(ET-1), adrenomedullin (AM), and transforming growth factor-beta (TGF-beta) among different stages of ulcer development. A total of 82 cases were studied. Ulcers were located in the gastric angulus in 51 cases. All cases were positive for Helicobacter pylori (Hp). Ten cases were in the active stage (GA), 18 were in the healing stage (GH), and 28 were in the scarring stage (GS). As control, 17 cases of Hp-positive gastritis (gast+) and 14 of Hp-negative gastritis (gast-) were studied. The concentrations of endothelin (ET) and TGF-beta were in the order of GH> GA> GS, and those of AM were in the order of GS > GH > GA. On immunostaining, ET stained positively in endothelial cells and vascular smooth muscle cells (VSMCs) during the GH and GS stages, and AM stained positively in histiocytes during GA, GH and GS, and also stained positively in glandular epithelia and smooth muscle fibers during GH and GS. When our results were reviewed with respect to the regulation of vascular tonus and the proliferation of VSMCs, ET and AM were considered to have roles in the regulation of proliferation.

Adrenomedullin↗

PubMed2000

Changes of nitric oxide and growth factors during gastric ulcer healing.

We measured the concentrations of vascular endothelial growth factor (VEGF), nitric oxide and endothelin-1 (ET-1) in the gastric mucosa and examined the relationships between these factors. VEGF, nitric oxide and ET participate in angiogenesis and vascular remodeling, important elements of gastric ulcer healing. We studied cases of gastric ulcer as confirmed by endoscopic examination. All 61 cases in the angulus were positive for Helicobacter pylori (Hp). Fifteen cases were active stage (GA), 23 were healing stage (GH), and 23 were scarring stage (GS). As control, 17 cases of Hp-positive gastritis (gast+) and 14 cases of Hp-negative gastritis (gast-) were studied. Biopsy samples taken from the angulus during endoscopic examination were frozen and sliced into thin sections. ET was measured by enzyme immunoassay, VEGF was measured by enzyme-linked immunosorbent assay (ELISA) and nitric oxide was measured in terms of metabolite oxides of nitrogen (NOx) as described by Griess. ET, VEGF and inducible nitric oxide synthase (iNOS) were immunostained. The GA group had the highest concentration of NOx, suggesting that nitric oxide participates in the early stage of mucosal repair. In the GH group, all three factors showed high concentrations, suggesting that all may be involved in increased production. In the GS group, all three factors were significantly lower than in the GA and GH groups. Immunohistochemical studies showed that the distribution of ET- and iNOS-positive cells differed according to the ulcer stage. In particular, ET- and iNOS-positive cells in the vascular wall were primarily endothelial cells during GA and GH and vascular smooth muscle cells (VSMCs) during GS. These findings suggest that endothelial cells produce increased amounts of ET, nitric oxide and VEGF early in ulcer healing, a period of active endothelial cell repair and angiogenesis. During the scarring stage, vascular remodeling may result from the effects of ET and nitric oxide in regulating the proliferation of VSMCs. Our results suggest that VEGF. nitric oxide and ET participate in angiogenesis, vascular remodeling and mucosal regeneration during ulcer healing.

Endothelial Growth Factors↗

PubMed2000

Endoscopic treatment of vesicoureteral reflux in children with glutaraldehyde cross-linked bovine dermal collagen. Short-term results.

BACKGROUND: Endoscopic treatment using glutaraldehyde cross-linked (GAX) collagen was conducted on 4 children with bilateral primary vesicoureteral reflux (VUR)..... a 1-year-old boy and three 5- to 8-year-old girls $B!D (Ball having a history of repeated hospitalization for fever due to acute pyelonephritis, visiting as pediatric outpatients regularly and receiving antibiotics continuously. By international VUR classification, 4 ureters were grade 3, 2 grade 4, and 2 grade 5. METHODS: After nonallergy to GAX collagen was confirmed intracutaneously, a needle was used through a 9.5 Fr cystoscope channel to puncture bladder mucosa 4 to 5 mm from the affected ureteral orifice at 6 o'clock under general anesthesia; 1.1 to 1.9 ml of GAX collagen was injected immediately below affected orifices. RESULTS: Three months after surgery, voiding cystourethrography showed reflux had disappeared in 6 ureters, for a short-term success rate of 75%. VUR in the Remaining 2 ureters improved from grade 3 to 1 and from grade 5 to 4. No postoperative urinary tract infection occurred and antibiotics were stopped. CONCLUSION: Since GAX collagen is less viscous than Teflon paste, it is easily injected into submucosa, does not form granuloma or migrate to other organs, and is noncarcinogenic. Endoscopic VUR treatment using GAX collagen is indicated when less invasion and shorter hospitalization are considered, although it requires general anesthesia, which itself involves some risk.

Child↗