PubMed Health⌕ Search

Biomedical subjects

T Tanikawa

Publications and source records attributed to T Tanikawa.

At least 37 records · Page 2Linked to original sources
PubMed1997

Ex vivo partial nephrectomy and partial kidney autotransplantation for renal pelvic carcinoma in a functionally solitary kidney: case report.

A 46-year-old Japanese man was diagnosed with a left renal pelvic carcinoma and a contralateral hypoplastic kidney. The tumor was adjacent to the renal pelvis and was considered too difficult to completely resect in situ. The patient was treated by ex vivo partial nephrectomy of the left kidney followed by autotransplantation of the remaining renal segment. A pathologic evaluation revealed a transitional cell carcinoma, G2, pT3. Graft function recovered satisfactorily postautotransplantation and no significant complications developed during the postoperative period. The patient is alive and doing well 12 months postoperatively with no evidence of tumor recurrence.

Carcinoma, Transitional Cell↗
PubMed1997

Volumegraph (overlaid three-dimensional image-guided navigation). Clinical application of augmented reality in neurosurgery.

OBJECTIVE: We have developed an overlaid three-dimensional image (Volumegraph)-guided navigation system that allows navigation during operative procedures. The three-dimensional image is superimposed on the patient's head and body via a semi-transparent mirror. The Volumegraph can display three-dimensional images in the air by a light beam which is based on CT/MRI. METHOD: The system consists of a Volumegraph (thin plate of three-dimensional recorded medium), a Volumegraphscope and an original designed triangular-shaped marker system for registration. The three-dimensional data obtained from CT and MRI before the operation were processed by a computer. Such image data are applied for preoperative investigation to recognize the three-dimensional structure of organs and tumor. These reconstructed three-dimensional images were superimposed and registered at the patient's head according to a fiducial marker (registration). Then the operator can operate with this three-dimensional-image-guided navigation system. RESULTS: Based on clinical application in 7 cases, the system was found to be advantageous because the surgical procedures could be navigated easily by augmented reality in the surgical field. Invisible parts of the surgical field were supplemented with the overlaid three-dimensional images (Volumegraph) as if it were the virtual operative field. At another time, spatial positioning and overlaid visualization by the Volumegraph was useful for identifying anatomical structures and functional location in the image. CONCLUSION: This preliminary study of overlaid three-dimensional-image-guided navigation demonstrated its clinical usefulness. The application of augmented reality in the surgical field makes it possible to do a neurosurgical intervention easily and accurately.

Brain Neoplasms↗
PubMed1997

Mechanisms of coronary microvascular dilation induced by the activation of pertussis toxin-sensitive G proteins are vessel-size dependent. Heterogeneous involvement of nitric oxide pathway and ATP-sensitive K+ channels.

G proteins are critically important mediators of many signal transduction systems. In the present study, we investigated the effect of direct activation of pertussis toxin (PTX)-sensitive G protein (GPTX) on coronary arterial microvascular tone in 37 open-chest anesthetized dogs in vivo. Coronary arterial microvessels on the surface of the beating left ventricle were visualized by performing fluorescence coronary microangiography using an intravital microscope with a floating objective system. Microvessels were divided into two groups, small microvessels (inner diameter, < or = 130 microns) and large microvessels (inner diameter, > 130 microns). Topically applied mastoparan (G protein activator, 10, 30, and 100 mumol/L) produced homogeneous microvascular dilation in a concentration-dependent manner (10 mumol/L, 7.9 +/- 2.0%; 30 mumol/L, 10.3 +/- 2.4%; and 100 mumol/L, 16.7 +/- 4.5% in small microvessels; 10 mumol/L, 5.3 +/- 1.2%; 30 mumol/L, 9.8 +/- 2.5%; and 100 mumol/L, 15.5 +/- 3.9% in large microvessels). These dilations were reversed to constriction by pretreatment with PTX (300 ng/mL, 2 hours) in both microvessel groups. Blockade of nitric oxide production by NG-nitro-L-arginine (LNNA, 300 mumol/L) offset the mastoparan-induced dilation in large microvessels but not in small microvessels. Cosuperfusion of glibenclamide (10 mumol/L) with LNNA produced constriction of all sizes of microvessels in response to mastoparan, whereas charybdotoxin (10 nmol/L) did not affect the mastoparan effect. Pretreatment with glibenclamide alone reversed mastoparan dilation to constriction in small microvessels, whereas it only offset the dilation without producing constriction in large microvessels. We conclude that the activation of GPTX produces homogeneous coronary arterial microvascular dilation and that the underlining mechanisms of the dilation are vessel size dependent. The L-arginine-nitric oxide pathway mediates the dilation only in large microvessels, whereas ATP-sensitive K+ channel activation plays a central role in the dilation of small microvessels when GPTX is directly activated. ATP-sensitive K+ channels are also involved in the dilation of large microvessels in a synergistic fashion with nitric oxide production.

Adenosine Triphosphate↗
PubMed1997

[Objective evaluation of selective peripheral denervation for spasmodic torticollis].

The authors evaluated the results of selective peripheral denervation (SPD) of posterior rami of the cervical spinal nerves and/or the accessory nerve for spasmodic torticollis. Five patients underwent seven operations in total and the results were evaluated with the modified Tsui's score which was used in the clinical trial of botulinum toxin (BTX) for torticollis in Japan. The preoperative score was 10.8 +/- 2.2 (mean +/- S.D.) and the postoperative score was 1.4 +/- 1.7. The score changes indicated the effects of the operation as "excellent" in four cases and "good" in one case. These results indicate that SPD is superior to BTX in terms of control of symptoms in spasmodic torticollis. After the initial operation, however, two patients showed the so-called "mole-hitting game phenomenon" in which normal muscles develop abnormal contraction after denervation of abnormal muscles. This forced us to perform the second operations. Although this phenomenon was first described in botulinum toxin treatment, this is probably the first report in surgically denervated cases.

Adult↗
PubMed1996

[Kinetics of peripheral blood CD34-positive cells and optimal timing of blood stem cell harvest after urological anticancer chemotherapy].

PURPOSE: We evaluated the changes in stem cells in peripheral blood and the optimal timing for harvesting peripheral blood stem cells (PBSCs) following the administration of conventional cancer chemotherapy in patients with urological malignancies. PATIENTS AND METHODS: We evaluated the changes in PBSCs after the administration of cancer chemotherapy in 12 patients with urological malignancies (6 testis cancer, 3 bladder cancer, 3 prostate cancer) using flowcytometry analysis of CD34, a marker of blood stem cell. We evaluated the optimal timing for PBSCs harvesting following the administration of conventional cancer chemotherapy in 6 patients with urological malignancies (2 patients with testis cancer, 3 patients with prostate cancer, 1 patient with bladder cancer) using flowcytometry analysis of CD34 and granulocyte-macrophage colony-forming units (CFU-GM) counts. PBSC samples from 2 patients with prostate cancer were analyzed by the reverse transcriptase-polymerase chain reaction (RT-PCR) method to detect prostate cancer cells. RESULTS: The percentages of CD34-positive cells tended to increase in the peripheral blood during the period of convalescence that followed the induction of marked myelosuppression produced by the cancer chemotherapy. The peak in CD34-positive cells occurred between days 15 and 31 after beginning of cancer chemotherapy. The percentage of CD34-positive cells was increased in the mononuclear cells in harvested PBSCs. The percentages of CD34-positive cells in peripheral blood and in mononuclear cells harvested from PBSCs was correlated with the CFU-GM counts in harvested PBSCs. The CFU-GM counts peaked between days 16 to 31 following cancer chemotherapy. RT-PCR detected prostate-specific antigen (PSA) mRNA expression in PBSCs obtained from 1 of the 2 patients with prostate cancer. An amount of contamination with PSA mRNA reduced as chemotherapy was repeated. CONCLUSION: A sufficient number of PBSCs can be harvested after conventional cancer chemotherapy without the need for special cytotoxic mobilization that may be delayed the patient's treatment. RT-PCR results suggested that the harvested PBSCs should be examined for tumor cell contamination in patients with metastasis in bone marrow. If a sufficient amount of PBSCs will be harvested, the PBSC samples from the patient with bone marrow metastasis after repeated chemotherapy should be used by priority for PBSC transplantation as of today.

Adolescent↗
PubMed1996

[Nephron sparing surgery for synchronous and asynchronous bilateral renal cell cancer. A procedure using intraoperative ultrasonography, argon beam coagulator and fibrin glue].

BACKGROUND: Bilateral renal cell cancer (RCC) is an imperative indication of nephron sparing surgery (NSS). In the present study, we examined a new modality for NSS; intraoperative ultrasonography, argon beam coagulator (ABC) and fibrin glue. PATIENTS AND METHODS: We performed NSS against 7 kidneys in 5 patients, including 3 with synchronous and 2 with asynchronous tumors. Radical nephrectomy was performed on the contralateral kidney in 2 patients including one with asynchronous and the other with synchronous RCC. RESULTS: To examine satellite lesions and exact tumor extent within the kidney, intraoperative ultrasound scan was performed for all cases. Intraoperative ultrasound scan was shown to be useful for the above mentioned purposes because of its high resolving power. After clamping of the renal artery and surface cooling, dissection of the kidney was done by knife holder or by ultrasonic aspirator. Hemostasis was made by figure eight sutures with chromic catgut or poliglecaprone 25 monofilament, followed by coagulation using ABC, and with fibrin glue. Duration of arterial clamp ranged 20 approximately 78 min under surface cooling. Major complication did not occur except urinary fistula in one case caused by inadequate placement of a double J ureteral catheter. Postoperative renal functions were well preserved and any additional therapy for daily life was not needed in each patient. CONCLUSION: For performing NSS, the use of intraoperative ultrasound scan, ultrasonic aspirator, ABC and fibrin glue seemed to be useful, encouraging us to widespread its indication.

Adult↗
PubMed1996

[Lessons from experience of bertrand's selective peripheral denervation for splenius type torticollis].

A 23-year-old male with splenius type torticollis underwent selective denervation of C1 and C2 roots and C3-C6 spinal posterior rami, with excellent results. Based on this experience, we stress the importance of dynamic EMG and thorough review of video recording for identifying the involved neck muscles. In the operative procedures, the nerve rami are identified under the semispinalis muscle. To dissect the correct plane under the semispinalis muscle, the key point to keep in mind is to follow the great occipital nerve to the proximal part. An ultrasonic blood flow meter is useful to locate the vertebral artery in the spaces between the occiput and the C1 lamina and between C1-C2 laminae. Because fine nerve branches run in the soft tissues over the laminae, to avoid transient neuroapraxia, dissection around the C1, C2 arches should not be carried out under the periosteum, as is usually done in case of laminectomy. Dissection of C1 and C2 rami as far as the very medial part is rather difficult because of bleeding from the venous plexus and the presence of the vertebral artery. Therefore, the intradural approach might be easier for sectioning the C1 and C2 roots. We would like to add these points to the original description by Bertrand.

Adult↗
PubMed1996

[A clinico-pathological study of cystic spinal Schwannomas].

It is not rare for a spinal Schwannoma to have cystic formations, but there are various opinions about the mechanism. Since the installation of MRI in our institution in 1989, we have experienced 4 cases of cystic spinal Schwannoma. The diagnosis of such lesions was based on identifying cystic formations histopathologically. Among these cases, tiny hemorrhages were noted microscopically in three of them along with hemosiderin depositions and phagocytes containing hemosiderin. Besides, there are also a lot of sinusoidal vessels with thin endothelium. Perhaps in these three cases, it is the tiny hemorrhages that resulted in degenerative changes which in turn caused the formation of microcysts. But in addition to the above findings, a lot of hyalinized vessels were also demonstrated in the angiomatous components of two cases. Therefore, it is also possible that the microcyst formation is secondary to the degenerative changes caused by ischemia within the tumors. On the other hand, in the only case without hemorrhage, neither phagocytes containing hemosiderin nor abnormal sinusoidal vessels could be found. In stead, a lot of clear foamy cells with positive lipid staining were seen. There may be some factors underlying the xanthomatous change of these tumors that cause their vacuolar formation from degenerated of the foamy cells. It is possible that all three factors mentioned above may act alone or in combination to contribute to the formation of cysts. At its late stage, a spinal Schwannoma may have various findings which can not be classified into either Antoni A or Antoni B type. In conclusion, a spinal Schwannoma can occasionally have cystic formations. Its mechanisms can be a hemorrhagic or an ischemic process occurring within the tumor.

Adult↗
PubMed1995

A new approach to the control of central deafferentation pain--spinal intrathecal baclofen.

We investigated the short-term effects of an intrathecal bolus injection of baclofen on central pain due to stroke or spinal cord injury. Pain relief was obtained in 64% of the patients. The effects developed 1-2 hours after the injection and continued for 10-24 hours. Both spinal segmental and supraspinal mechanisms may be involved in the production of baclofen-analgesia.

Afferent Pathways↗
PubMed1995

A new approach to control central deafferentation pain: spinal intrathecal baclofen.

Baclofen, an agonist of the gamma-aminobutyric acid (GABA) receptor, has antinociceptive effects, and its intrathecal administration reduces allodynic responses in animal models of neurogenic central pain. Such experimental studies lead to the hypothesis that neurogenic pain may be induced in part by functional abnormalities in spinal GABAergic systems. However, whether a GABAergic system is actually involved in human central pain is unknown. The authors investigated the effect of an intrathecal bolus injection of baclofen in 14 patients with central pain due to a stroke or spinal cord injury. Nine reported substantial pain relief they had never experienced previously. The effect appeared 1-2 h after the injection and persisted for 10-24 h. Allodynia and hyperalgesia, if present, were relieved as well. Pinprick and light touch sensations did not change in nonaffected regions. The results indicate that dysfunction of spinal GABAergic systems plays a role in the clinical expression of central pain. In clinical situations, continuous intrathecal infusion of baclofen seems feasible for relief of central pain.

Afferent Pathways↗
PubMed1994

mRNA and protein expression of p53 mutations in human bladder cancer cell lines.

We investigated mRNA and protein expression in p53 gene mutations in four human bladder cancer cell lines using polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) and Northern blot and Western blot analyses. The following mutations were identified in three of the four cell lines: a missense transversion at codon 110, a missense transition at codon 250 and a non-sense transversion at codon 126. These mutations were located outside previously identified hot spot codons and have rarely been reported in bladder cancer tissues or other neoplasms. Positive intranuclear p53 immunostaining in neoplastic cells in the two missense mutations and the premature stop codon in the non-sense mutation suggested the presence of structural and functional alterations in the p53 protein. Northern and Western blot analyses revealed either an intense or a weak p53 mRNA band together with an intense p53 protein band in the missense mutations, but no p53 mRNA or protein band in the non-sense mutation. A weak p53 mRNA band, but no distinct p53 protein band was observed in the cell line without a mutation and in normal control bladder cells. Our findings suggest that regulation of p53 expression in these cell lines differs at the post-transcriptional and/or post-translational level between the wildtype and the mutant p53 genes and also among different mutant p53 genes. The three cell lines with mutations were derived from high-grade carcinomas; the cell line without mutation was derived from a low-grade carcinoma.

Base Sequence↗
PubMed1994

Changes in urinary excretion of endothelin-1-like immunoreactivity in patients with testicular cancer receiving high-dose cisplatin therapy.

To assess the value of endothelin-1 (ET-1) in estimating renal injury in patients receiving high doses of cisplatin, urinary excretion of ET-1-like immunoreactivity (U-ET-1), beta 2-microglobulin (U-beta 2-MG), and N-acetyl-beta-d-glucosaminidase (NAG) were measured before, 1 week after, and 2 weeks after the administration of cisplatin in eight patients with testicular cancer (mean age, 33.3 years). Levels of U-ET-1/creatinine (Cr) during and 1 week after cisplatin treatment were significantly higher than before cisplatin treatment. There were no differences in U-ET-1/Cr levels during, 1 week after, and 2 weeks after cisplatin treatment. The level of U-beta 2-MG/Cr during cisplatin treatment was significantly higher than levels before, 1 week after, and 2 weeks after treatment. However, there were no differences in U-beta 2-MG/Cr levels before, 1 week after, and 2 weeks after cisplatin treatment. The level of U-NAG/Cr during cisplatin treatment was higher than levels before, 1 week after, and 2 weeks after treatment; U-NAG/Cr during cisplatin treatment was higher than levels before, 1 week after, and 2 weeks after treatment; U-NAG/Cr gradually decreased after cisplatin treatment. Among the three parameters, only U-ET-1/Cr maintained a higher level after cisplatin treatment. The U-beta 2-MG/Cr level returned most rapidly to normal after cisplatin treatment. Although U-ET-1/Cr did not show any significant correlation with U-NAG/Cr (r = 0.282, P = NS), it showed a significant correlation with U-beta 2-MG/Cr (r = 0.454, P < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Acetylglucosaminidase↗
PubMed1994

Urinary endothelin-1-like immunoreactivity in young male patients with testicular cancer treated by cis-platinum: comparison with other urinary parameters.

1. Urinary excretion of endothelin-1-like immunoreactivity and urinary excretion of other parameters (beta 2-microglobulin, N-acetyl-beta-D-glucosaminidase and microalbumin) were measured before, within 1 week after and 2 weeks after the administration of cis-platinum in five young male patients with testicular cancer (mean age 33.0 years) and were compared. 2. Urinary endothelin-1-like immunoreactivity/creatinine during, 1 week after, and 2 weeks after cis-platinum treatment was significantly higher than before cis-platinum. There was no difference in urinary endothelin-1-like immunoreactivity/creatinine during, 1 week after and 2 weeks after cis-platinum. 3. Among the four parameters, urinary endothelin-1-like immunoreactivity/creatinine showed the highest level after cis-platinum treatment. Urinary beta 2-microglobulin/creatinine most rapidly returned to normal levels after cis-platinum. 4. Although urinary endothelin-1-like immunoreactivity/creatinine did not show any significant correlations with urinary N-acetyl-beta-D-glucosaminidase (r = 0.291, not significant) or urinary microalbumin/creatinine (r = 0.076, not significant), it showed a significant correlation with urinary beta 2-microglobulin/creatinine (r = 0.475, P < 0.05). 5. These results suggest that endothelin-1 may be a sensitive urinary parameter in detecting cis-platinum-induced renal tubular injury.

Acetylglucosaminidase↗
PubMed1994

Correlation of p53 protein expression in human urothelial transitional cell cancers with malignant potential and patient survival.

The p53 gene product has been detected frequently in various human malignancies. We have studied the expression of p53 protein in urothelial transitional cell cancers (TCCs) and examined its correlation with pathologic grade, stage(pT) and patient survival. Specimens from 69 surgically-resected TCCs (38 cases of urinary bladder cancer, 17 cases of ureteral cancer and 14 cases of renal pelvic cancer) were examined by immunohistochemical staining, using two anti-p53 monoclonal antibodies, PAb1801 and PAb240, and a polyclonal antibody, CM-1. Twenty-six TCCs (37.6%) were positively stained by at least one of the three antibodies. Statistical analysis showed a significant correlation between p53 expression and high pathologic grade (p < 0.05, p < 0.001) or progressive pathologic stage (p < 0.01). In addition, in 51 of the patients who were available for follow-up (23 cases of urinary bladder cancer, 13 cases of ureteral cancer, and 15 cases of renal pelvic cancer), the correlation between p53 protein expression and prognosis was examined. The survival of patients exhibiting positive p53 protein expression was significantly worse than those with p53-negative tumors (p < 0.05). These results suggest that an immunohistochemical test for p53 protein may be a useful method of evaluating the malignant potential of TCCs. Additionally, expression of p53 protein in TCCs is an indicator of a poor prognosis which should be considered in drawing up treatment strategies.

Adult↗