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K Kihara

Publications and source records attributed to K Kihara.

At least 37 records · Page 2Linked to original sources
PubMed2001

Expression of aquaporins 7 and 8 in the developing rat testis.

Aquaporin (AQP) is a molecule that facilitates water permeability through cell membranes and is widely distributed in the mammalian body. Among members of the AQP family, AQP7 and AQP8 are predominantly expressed in the testis. This paper examined the expression of these two AQPs in the developing rat testis, using northern blot and immunohistochemistry to visualize their roles during the progression of spermatogenesis in the developing testis. In adult rats, expression of AQP7 was localized to spermatids, whereas AQP8 protein was observed in spermatocytes. In the developing testis, transcripts of AQP7 became detectable between 23 and 25 days post-partum, when round spermatids have been reported to appear. On the other hand, AQP8 mRNA was first detected between 13 and 16 days post-partum, consistent with the reported first appearance of spermatocytes (13-14 days). AQP7 and AQP8 proteins were detectable at 28 days post-partum. The results suggest that AQP7 and AQP8 appear in the testis in accordance with the maturation of germ cells, and are involved in spermatogenesis.

Aging↗
PubMed2001

DNA-damaging carcinogen 3-amino-1,4-dimethyl-5H-pyrido[4,3-b]indole (Trp-P-1) induces apoptosis via caspase-9 in primary cultured rat hepatocytes.

The mechanism of cytotoxicity induced by the DNA-damaging carcinogen 3-amino-1,4-dimethyl-5H-pyrido[4,3-b] indole (Trp-P-1) was investigated in primary cultured rat hepatocytes. Cytotoxicity was caused by intact Trp-P-1 and not by metabolically activated derivatives prepared using a recombinant yeast strain AH22/pAMR2 expressing rat cytochrome P450 1A1, and not by metabolically activated derivatives. We also found internucleosomal DNA fragmentation 6 h after treatment with 30 microM Trp-P-1, indicating that the cytotoxicity was due to the induction of apoptosis. After treatment with Trp-P-1, c-Myc protein level increased in a time-dependent manner and p53 protein also increased transiently with a subsequent increase in Bax protein level. This apoptotic pathway required the activation of caspase-9 as an initiator after leakage of cytochrome c into the cytosol from mitochondria and the activation of caspase-3 and -7 as executioners, but not caspase-1, -6 or -8 as measured using the corresponding peptide inhibitors and substrates or western blotting. The activated caspases in turn cleaved poly(ADP-ribose) polymerase as an intracellular substrate. Furthermore, we detected NUC18-like endonuclease activity during apoptosis induced by Trp-P-1. These findings suggest that this apoptosis may have a role against heterocyclic amine-type carcinogens in normal cells.

Animals↗
PubMed2001

[The comparison between mental image manipulation and distinctive feature scan on recognition memory of faces].

The authors proposed "mental image manipulation of expression" as processing strategy for faces, and investigated whether this strategy facilitates memory for faces or not. In the Experiment, four groups of subjects were assigned to a combination of a task (mental image manipulation of expression or distinctive feature scan) and a retention interval (short-term latency or long-term latency). Each task was followed by an unexpected yes-no recognition test in which identical pictures of the target faces or the same person's expression-changed faces were randomly presented with distractor faces. The mental image manipulation group was better than distinctive feature scan group in long-term storage. This result is considered as a long-term effect of imagery encoding and a configurational encoding by mental image manipulation.

Adolescent↗
PubMed2001

[Clinical effects of meropenem on infectious diseases in obstetrics and gynecology].

The efficacy and the safety of meropenem (MEPM) were examined in obstetric and gynecological infections and the results shown below were obtained. 1. The subjects were patients with infectious diseases during a non-pregnant period (n = 14), a pregnant period (n = 13) and a puerperal period (n = 11). After intravenous drip infusion of MEPM at 1-2 g/day, the response rate was 38/39 (97.4%) (Excellent: 13/39 (33.3%), Effective: 25/39 (64.1%)). 2. The response rates in a group receiving 1 g/day, a group receiving 2 g/day and a group receiving a combination of both were, respectively, 25/26 (96.2%), 9/9 (100%) and 4/4 (100%). 3. In cases that did not respond to previous treatments, the response rate to MEPM was 20/20 (100%). 4. In clinical efficacy classified by causative organisms, the rate of Excellent was 10/23 (43.5%) and the rate of Effective was 13/23 (56.5%), and the bacterial eradication rate was 21/23 (91.3%). 5. No subjective and objective adverse reactions or abnormalities in clinical laboratory tests due to administration of MEPM were observed.

Adult↗
PubMed2001

[Neoadjuvant chemotherapy for invasive bladder cancer].

Although radical cystectomy is the gold standard for invasive bladder cancer, about half of the patients develop distant metastases within two years after operation. Objectives of preoperative (neoadjuvant) chemotherapy in muscle invasive bladder cancer are eradication of micrometastasis and subsequent improvement of prognosis. Based on favorable outcome of M-VAC (methotrexate, vinblastine, adriamycin, cisplatin) therapy in advanced cases, several clinical trials have been performed. Unfortunately, results of the randomized prospective studies failed to demonstrate survival benefits. However, response to the preoperative chemotherapy has been found to be an excellent prognostic factor, and preservation of the bladder (complete preservation or partial cystectomy) is possible in selected cases with complete response. Moreover, good local control by neoadjuvant chemotherapy enables cystectomy in selected cases of locally-advanced cancer once considered unresectable, and may lead to suppression of intraoperative spread of the tumor cells.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed2001

[Efficacy of a single-day administration of levofloxacin for the prevention of urinary tract infections after urogenital examinations and treatments for outpatients].

The clinical efficacy of a single-day oral administration of levofloxacin (LVFX) for the prevention of urinary tract infections (UTI) after urogenital examinations and treatments for outpatients was assessed. A single-day oral administration of LVFX, 100 mg three times a day, was compared to a single dose intra-muscular injection of 100 mg netilmicin sulfate or 100 mg dibekacin sulfate. Three of 219 cases (1.4%) and 7 of 304 cases (2.3%) contracted UTI in the single-day oral administration group and the single dose intra-muscular injection group, respectively. Adverse reactions were observed in 3 of 219 cases (1.4%) and 27 of 304 cases (8.8%) in the single-day oral administration group and the single dose intra-muscular injection group, respectively. In the single dose intra-muscular injection group, UTI and adverse reactions were more severe than in the single-day oral administration group. Therefore, a single-day oral administration of LVFX was superior to a single dose intra-muscular injection of netilmicin sulfate or dibekacin sulfate in the prevention of UTI with less probability of the adverse effects. A single-day oral administration of LVFX was concluded to be sufficient for the prevention of UTI caused by examinations and treatments for outpatients.

Administration, Oral↗
PubMed2001

[A remarkably improved multimetastatic gastric cancer with the use of TS-1 and CDDP].

A 62-year-old male presented to our hospital with jaundice. On the abdominal ultrasound and abdominal CT, there was evidence of multiple, massive liver metastases with dilatation of intrahepatic bile ducts, thickened wall of the stomach from the body to the antrum, direct invasion to the pancreas, multiple lymph node metastases, and ascites. We believed it was Stage IV and too far advanced for surgery. Therefore, ST-1 60 mg bid was started, and CDDP 50 mg was infused in the seventh week. On the follow-up CT and ultrasound three months later, the thickening of the gastric wall and the lymph node metastasis had improved and the border between the stomach and the pancreas had become clearer. The liver metastases seen on both lobes had decreased significantly both in size and number. The dilatation of the intrahepatic bile ducts disappeared, and the liver function normalized. No side effects were evident during the treatment with the medications.

Antimetabolites, Antineoplastic↗
PubMed2000

Sympathetic efferent pathways projecting to the prostate in the dog.

BACKGROUND: The laterality of the signals passing through the splanchnic nerves to each lobe of the prostate has not been studied. METHODS: Bilateral distribution of sympathetic signal to both lobes of the canine prostate was determined by measuring contraction of the prostate by stimulation of thoracolumbar splanchnic nerves with or without transection of unilateral hypogastric nerve (HGN). RESULTS: The 2nd-5th lumbar splanchnic nerve (LSN) stimulation elicited prostatic contraction. Twenty-five of 27 right LSN stimulations elicited contraction of the lobe, 21 bilaterally and 4 unilaterally. Twenty-three of 25 left LSN stimulations elicited contraction of the lobe, 22 bilaterally and one unilaterally. The above stimulations did not elicit a dominant response in the lobe of the stimulated side. After transection of the right HGN, right and left LSN stimulation elicited contraction of the lobe bilaterally and did not induce dominant response in the lobe of the non-lesioned side. After transection of the left HGN, similar results were obtained. CONCLUSIONS: The results indicate that each of the LSNs sends signals to bilateral lobes via multiple routes with two crossing sites at the level of the caudal mesenteric plexus and prostate, and that the signals elicit contraction of the lobe without a dominant side.

Animals↗
PubMed2000

Cellular senescence of a human bladder carcinoma cell line (JTC-32) induced by a normal chromosome 11.

Human chromosome 11 is expected to carry tumor suppressor genes for a variety of human cancers, including bladder carcinoma. To examine the functional role of a putative tumor suppressor gene(s) on this chromosome in the development of bladder carcinoma, we performed microcell-mediated transfer of chromosome 11 into the bladder carcinoma cell line, JTC-32. Fifteen of 20 colonies formed by the transfer experiment showed a remarkable change in cell morphology. They flattened and ceased growing, or senesced, prior to 10 population doublings. The presence of transferred chromosome 11-derived fragments in the growth-arrested cells was confirmed by PCR-based polymorphism analyses. The remaining 5 microcell hybrid clones exhibited a parental cell-like morphology, and presumably escaped from senescence, which was accompanied by deletions and/or rearrangements of the transferred chromosome 11. On the other hand, a transferred normal chromosome 7 neither changed the cell morphology nor arrested the cell growth. These results support the hypothesis that chromosome 11 contains a gene or genes which restore the senescence program lost during the immortalization process of JTC-32 cells.

Aged↗
PubMed2000

Preoperative concurrent chemoradiotherapy against muscle-invasive bladder cancer: results of partial cystectomy in elderly or high-risk patients.

BACKGROUND: Good local control has been reported in cases of muscle-invasive bladder cancer treated by chemoradiotherapy and transurethral resection (TUR). However, definitive irradiation or extensive chemotherapy is often intolerable for elderly or poor-risk patients. We report here benefits of partial cystectomy after concurrent low-dose chemoradiotherapy for high-risk patients. METHODS: Thirty-seven patients with localized muscle-invasive bladder cancer (T2-T4) were treated with concurrent cisplatin (50-100 mg/body x 2 courses) and pelvic irradiation (40 Gy) preoperatively. Among 17 patients (46%) who achieved complete response (CR), 10 were not suitable for radical cystectomy and underwent partial cystectomy. Radical cystectomy was performed in 24 cases [CR = 6, partial response (PR) = 18]. Two patients (one CR and one PR) rejected open surgery and were treated by TUR of the primary site. One no change (NC) patient received no further treatment because of mental disorder. RESULTS: Median follow-up was 12 months (range 2-37 months). Fifteen of 36 evaluable cases (42%) achieved a pathological T0 response (no residual tumor). Estimated 3-year disease-free survival was 56% for all patients and 100% for T0 responders. Seven of 21 patients with pathological persistent tumor developed local recurrence (three patients) or distant metastasis (four patients). All of the 10 patients (eight with T0 response and two with a small residual tumor nest) who underwent partial cystectomy were recurrence-free for an observation period of up to 3 years. CONCLUSIONS: Bladder preservation by partial cystectomy may be a choice for patients who show a good response to preoperative chemoradiotherapy and are not suitable for radical cystectomy.

Aged↗
PubMed2000

Sexual dimorphism in the regulation of meiotic process in the rabbit.

Meiosis, mitosis, and apoptosis during fetal and postnatal periods were investigated in order to explore mechanisms of sexual dimorphism in initiation of germ cell meiosis. Gonads were obtained from Japanese white rabbits from 23 to 51 days postcoitum (dpc). Gonadal thin sections were stained with hematoxylin and eosin. Germ cell alkaline phosphatase and apoptosis were detected with histochemical and immunohistochemical methods, respectively. In the ovary, meiotic germ cells were initially recognized at 29 dpc and arrested after enclosure within follicles. Similarly, meiotic germ cells were recognized outside seminiferous tubules at 29 dpc, but no meiotic figures were identified in intratubular spaces. Apoptotic germ cells were not recognized in the intratubular spaces before 35 dpc, and no apoptotic figures were recognized in the ovary during the period studied. In conclusion, the initiation of meiosis in testicular interstitial tissue at the time comparable to that in the ovary indicates that germ cells of both sexes have the ability to enter meiosis during the same stage of fetal development; and it appears most likely that delayed initiation of meiosis in the intratubular space is attributable to meiosis-inhibiting substance(s) present in seminiferous tubules.

Animals↗
PubMed2000

Significance of carbohydrate antigen sialyl-Lewis X, sialyl-Lewis A, and possible unknown ligands to adhesion of human urothelial cancer cells to activated endothelium.

OBJECTIVE: To assess the contribution of the carbohydrate antigens, sialyl-Lewis X (sLe(x)) and sialyl-Lewis A (sLe(a)), which are known to be ligands for E-selectin, to the adhesion between human urothelial cancer cells and cytokine-activated human endothelial cells. MATERIALS AND METHODS: We studied the expression of sLe(x) and sLe(a) antigens of three bladder cancer cell lines (JTC 30, JTC 32, and T24) by flow cytometry and the adherence to interleukin 1beta-activated human umbilical vein endothelial cells (HUVEC). RESULTS: JTC 30 and JTC 32 cells expressed both sLe(x) and sLe(a) antigens, and showed adhesion to activated HUVEC, which was completely abolished by anti-E-selectin antibody. T24 cells expressed neither sLe(x) nor sLe(a) antigen, and did not adhere to activated HUVEC. Each of anti-sLe(a) or anti-sLe(x) antibody partially blocked the attachment of JTC 30 cells to activated HUVEC, and combination of these antibodies almost completely blocked the adhesion. The combination of antibodies did not significantly influence the adhesion of JTC 32 cells. CONCLUSION: These results indicate that both sLe(a) and sLe(x) carbohydrate antigens are involved in E-selectin-mediated adhesion of some urothelial cancers, and that there might be unknown ligands for E-selectin on urothelial cancer cells.

Antigens, Tumor-Associated, Carbohydrate↗
PubMed2000

Detection of biomarkers for apoptosis in rat liver after perfusion with 3-amino-1,4-dimethyl-5H-pyrido[4,3-b]indole (Trp-P-1).

We previously demonstrated that 3-amino-1,4-dimethyl-5H-pyrido[4,3-b]indole (Trp-P-1) induced apoptosis in primary cultured rat hepatocytes. In this study, we investigated apoptotic biomarkers in rat liver after perfusion with 30 microM Trp-P-1 as preliminary experiments for in vivo study. Induction of c-Myc and p53 protein and the activities of caspase-3, -6, and -8 were detected in Trp-P-1-perfused liver. In addition, Trp-P-1 modulated the DNA binding activity of the apoptosis-related transcription factors, NF-kappaB and AP-1. These results imply a possibility that Trp-P-1 would induce apoptosis in vivo.

Animals↗
PubMed2000

Myocardial scintigraphy using iodine-123 15-(p-iodophenyl)-3-R, S-methylpentadecanoic acid predicts the response to beta-blocker therapy in patients with dilated cardiomyopathy but does not reflect therapeutic effect.

Myocardial fatty acid metabolism is disturbed in patients with idiopathic dilated cardiomyopathy. Myocardial scintigraphy using iodine-123 15-(p-iodophenyl)-3-R, S-methylpentadecanoic acid(BMIPP) was used to assess the response to beta-blocker therapy in 19 patients with dilated cardiomyopathy. BMIPP myocardial scintigraphy was performed before and 6 months after initiating beta-blocker therapy with metoprolol. Cardiac BMIPP uptake was assessed as the total defect score (TDS) and heart-to-mediastinum activity (H/M) ratio. Patients were classified retrospectively as responders with an improvement of at least one functional class (New York Heart Association) or an increase in ejection fraction of > or = 0.10 at 6 months, or as nonresponders meeting neither criterion. Responders had a significantly better pretreatment TDS (p < 0.005) and H/M ratio (p < 0.0001) than nonresponders. TDS exhibited no significant changes over 6 months in either group (responders: 13.2 +/- 3.7 vs 12.5 +/- 3.3; nonresponders: 20.8 +/- 6.5 vs 20.5 +/- 3.0). Responders showed no significant changes in H/M ratio (2.47 +/- 0.28 vs 2.43 +/- 0.42); paradoxically, nonresponders showed a significant increase from 1.82 +/- 0.11 to 2.10 +/- 0.19 (p < 0.05), suggesting that beta-blocker therapy protected the myocardial fatty acid metabolism even in the absence of clinical improvement. BMIPP myocardial scintigraphy provides a prediction of response to beta-blocker treatment, but does not reflect the therapeutic effect in responders at 6 months.

Adrenergic beta-Antagonists↗
PubMed1999

Treatment for accidental occlusion of the hepatic artery after hepatic resection: report of two cases.

Two patients in whom accidental hepatic artery occlusion (HAO) occurred after hepatic resection (Hx) were reported. A 59-year-old female who underwent Hx for hepatocellular carcinoma with underlying liver cirrhosis developed HAO on postoperative day (POD) 14 and died of hepatic failure on POD 23. The autopsy findings showed multiple necrosis in the remnant liver and an extraluminal hematoma of the hepatic artery, suggesting an injury caused by Pringle's maneuver. The second case was a 53-year-old male who underwent Hx for cholangiocarcinoma without any underlying liver disease. He developed HAO on POD 6, and radiological studies indicated a pseudoaneurysma formation and severe stenosis of the hepatic artery. It was speculated that the cause of the HAO was intraluminal injury of the hepatic artery during an angiographic study conducted prior to Hx. Partial arterialization of the portal vein was performed, following which his liver function test results improved. In both cases, measuring the serum hepatocyte growth factor level and the hepatic vein oxygen saturation proved useful, not only for determining the degree of liver injury, but also for predicting the outcome after treatments for HAO. Furthermore, the partial arterialization of the portal vein for HAO after Hx may rescue the normal remnant liver.

Aneurysm, False↗