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Biomedical subjects

T Tominaga

Publications and source records attributed to T Tominaga.

At least 19 recordsLinked to original sources

Expression of matrix metalloproteinases (MMPs) and tissue inhibitor of metalloproteinase (TIMP) in cerebral cavernous malformations: immunohistochemical analysis of MMP-2, -9 and TIMP-2.

OBJECT: Hemorrhage from cerebral vascular malformations such as cerebral cavernous malformation (CCM) can result in significant mortality and morbidity, but its underlying mechanism is undetermined. Excessive degradation of the vascular matrix by matrix metalloproteinases (MMPs), proteolytic enzymes that degrade all the components of extracellular matrix, can lead to instability of the vascular structure and can thereby cause bleeding. Thus we examined the expression of MMPs and tissue inhibitors of metalloproteinase (TIMP) in CCM. PATIENTS AND METHODS: We performed immunohistochemistry for MMP-2, -9, and TIMP-2 using Paraffin-embedded sections of the surgical specimens obtained from seven patients with CCM. All patients had a history of hemorrhage from CCM. FINDINGS: In all patients (7/7, 100%), MMP-2 and -9 were strongly expressed in endothelial cells of CCMs. Endothelial expression of TIMP-2 was also evident in all seven patients. In contrast, MMP-2, -9 and TIMP-2 were not identified in adjacent normal brain tissue. CONCLUSION: We found that CCM showed the increased endothelial expression of MMP-2, -9, and TIMP-2. Endothelial expression of MMPs and/or TIMP may affect the vascular matrix stability, and thus can contribute to hemorrhage from CCM.

Adult↗

Modified surgical technique for the treatment of idiopathic spinal cord herniation.

OBJECTIVE AND IMPORTANCE: Spinal cord herniation is not a common disease and only 80 cases have been reported to the best of our knowledge. The treatment of this lesion is thought to be difficult and a better surgical technique has not been established. CLINICAL PRESENTATION: A 57-year-old man presented with gradually worsening spastic gait and hypoesthesia in the bilateral lower extremities suspected to be due to Brown-Séquard syndrome. Magnetic resonance imaging showed a thoracic spinal cord herniation into the anterior hiatus at T2 - 3. INTERVENTION: A modified technique of closure of the hiatus in front of the herniation was performed. A surgical artificial dural membrane was introduced between the herniated portion of the thoracic cord and the dural hiatus and was placed to cover the whole dural defect in order to minimize the operative procedure at the ventral side of the spinal cord. On subsequent magnetic resonance imaging, the herniation was remarkably improved and patient's symptoms were abolished. CONCLUSION: The direct widening of the dural defect has been reported to be the only treatment providing a good outcome. We suggest that our modified technique for its closure can be as safe and effective as the direct widening method.

Brown-Sequard Syndrome↗

Development of shock wave assisted therapeutic devices and establishment of shock wave therapy.

In order to exploit systems for shock wave therapy, we are working for the development of clinical devices that are based on the concept of shock waves or related phenomena. The paper describes these new therapeutic devices designed for the minimally invasive approach to vascular thromboloysis, selective dissection of tissues, and drug or DNA delivery. To investigate the response of cells to shock loading, a precise method of shock waves generation in space and time has been developed. This method has been studied for application in cardiovascular therapy, cancer treatment, and cranioplasty in close vicinity of the brain. A laser ablation shock wave assisted particle acceleration device has been developed for delivering drug and DNA into soft targets in the human body. The penetration depth of microparticles observed in the experimental targets is believed to be sufficient for pharmacological treatments. In order to achieve an efficient method for rapid revascularization of cerebral thrombosis, a laser induced liquid jet (LILJ) system has been developed. The LILJ has been successfully applied for selective dissection of soft tissue preserving nerve and blood vessels. The system has been further improved by using piezoelectric actuators to drive the liquid jets, as an alternative to pulse laser.

Animals↗

Listeriolysin O derived from Listeria monocytogenes inhibits the effector phase of an experimental allergic rhinitis induced by ovalbumin in mice.

Listeriolysin O (LLO) derived from Listeria monocytogenes is highly capable of inducing interleukin (IL)-12, IL-18 and interferon (IFN)-gamma, and facilitates the generation of Th1 cells. We have recently shown that recombinant LLO (rLLO) inhibits generation of ovalbumin (OVA)-specific Th2 immune response by skewing maturation of antigen-specific T cells into Th1 cells. In the present study, we investigated the effect of rLLO on the effector phase of Th2-dependent allergic rhinitis in BALB/c mice sensitized with OVA. In mice sensitized intraperitoneally and challenged intranasally with OVA, nasal allergic symptoms such as sneezing and nose-scratching were observed at a high frequency. A high titre of anti-OVA IgE antibody was detected in sera and a large number of eosinophils migrated into the nasal tissue. However, rLLO treatment during the intranasal challenge inhibited the allergic symptoms, production of anti-OVA IgE antibody and eosinophil infiltration. Though rLLO did not affect antigen-specific cytokine production from splenic CD4(+) T cells, rLLO significantly suppressed OVA-specific IL-4 and IL-5 production from nasal mononuclear cells. We further found that rLLO inhibited the recruitment of CD4(+) T cells in nasal mucosa, and diminished the transcription and cell surface expression of CCR4 on splenic CD4(+) T cells. Moreover, rLLO was able to inhibit the passive cutaneous anaphylaxis reaction mediated by anaphylactic antibodies (IgE and IgG(1)) and mast cells. Taken together, these data showed that rLLO suppresses the effector phase of allergic rhinitis by inhibition of Th2 cell recruitment to nasal mucosa and type I allergic reaction.

Animals↗

Malignant transformation of pleomorphic xanthoastrocytoma.

A 31-year-old woman presented with a pleomorphic xantho-astrocytoma (PXA) manifesting as epilepsy. The tumour was partially resected. Histological examination revealed cellular pleomorphism and cytoplasmic vacuolation consistent with PXA, but no mitoses, necrosis, or endothelial proliferation. Follow-up neuro-imaging showed the residual tumour had grown rapidly with dissemination in the spinal cord. The recurrent lesion was totally resected and was shown to be glioblastoma. The patient has survived without signs of recurrence for 36 months after adjuvant radiochemotherapy. The biological behaviour of PXA cannot be predicted based on the histological features and careful follow up is essential.

Adult↗

Intraoperative localisation of the lip sensory area by somatosensory evoked potentials.

Accurate localisation of the central sulcus enables maximum tumour resection with minimum morbidity in peri-Rolandic surgery. We investigated intraoperative somatosensory evoked potentials (SSEPs) with combined recording of lower lip and median nerve stimuli during craniotomy in nine patients with peri-Rolandic glioma. Using a custom clip electrode, the lip mucous membrane was stimulated with biphasic pulses with 0.2 ms duration, 10-14 mA intensity and a frequency of 0.7 Hz. Polarity inversion of the SSEP was detected across the central sulcus using median nerve and/or lower lip stimulation in eight of the nine patients in whom the tumour did not infiltrate the lip or hand sensory area. Recording of SSEPs with lower lip stimulation is useful if the resection margin is planned lateral to the hand representation area, if the hand representation area is not exposed by the craniotomy, or if the SSEPs for median nerve stimulation are not clear due to tumour infiltration.

Adult↗

Stereotactic radiosurgery followed by whole ventricular irradiation for primary intracranial germinoma of the pineal region.

Intracranial germinomas can be cured by radiotherapy and/or chemotherapy. Three patients with pineal germinoma were treated with stereotactic radiosurgery using the gamma knife (10 - 12 Gy) to the tumors followed by whole ventricular irradiation (24 Gy). All patients had solitary pineal tumor measuring less than 3 cm, clinically compatible with germinoma, normal cerebrospinal fluid (CSF) and serum levels of alpha-fetoprotein and beta-human chorionic gonadotropin, no disseminated disease on spinal magnetic resonance (MR) imaging, and no abnormal CSF cytology. All patients showed complete response to the combined radiotherapy, and MR imaging has shown no recurrence of the tumor. Combined radiotherapy using gamma knife radiosurgery is effective for pineal germinoma, and reduced the cost of treatment with less need for hospitalization.

Adult↗

Listeriolysin O, a cytolysin derived from Listeria monocytogenes, inhibits generation of ovalbumin-specific Th2 immune response by skewing maturation of antigen-specific T cells into Th1 cells.

Listeriolysin O (LLO), a cholesterol-dependent cytolysin derived from Listeria monocytogenes, is a potent inducer of interleukin (IL)-12, IL-18 and interferon (IFN)-gamma. We have shown that LLO facilitates development of T cells mediating protective immunity against L. monocytogenes through the induction of IFN-gamma production at an early stage. Based on this finding, it is postulated that LLO inhibits differentiation of Th2 cells and the Th2 immune response. By using a murine model of ovalbumin (OVA)-induced allergic rhinitis, we investigated whether LLO has an ability to modulate the Th2-type immune disorder. In mice sensitized intraperitoneally with ovalbumin (OVA)/alum and challenged intranasally with OVA, a large number of eosinophils migrated into the nasal tissue, and high titres of anti-OVA IgE and IgG(1) antibodies were detected in sera. However, LLO treatment during sensitization markedly inhibited the eosinophil infiltration and production of these anti-OVA antibodies. A large number of T cells from mice sensitized and challenged with OVA produced high level of IL-4 and IL-5 but not IFN-gamma after stimulation with OVA. In contrast, OVA-specific IFN-gamma-producing T cells were preferentially induced in mice treated with LLO at the time of sensitization. In the absence of LLO administration, the expression level of GATA-3 and SOCS-3 in CD4(+) T cells was enhanced after sensitization with OVA. LLO treatment resulted in a reduction of GATA-3 and SOCS-3 expressions but induced the transcription of T-bet instead. Taken together, these data show clearly that LLO is capable of inhibiting Th2 immune response by skewing differentiation of antigen-specific T cells into Th1 cells.

Animals↗

Cytological affinities and interfertilities between Lolium temulentum and L. persicum (Poaceae) accessions.

Interspecific crossing between L. temulentum L. and L. persicum Boiss. & Hohen. ex Boiss. was performed to clarify their interfertility based on the results of chromosome pairing, pollen fertility and seed set. Both parents were normal with a high percentage of chromosome association of ring bivalents in contrast to rod bivalents at metaphase I, pollen fertility and seed set, but F1 hybrids showed different proportions of them for each crossing combination. Chromosome affinity expressed by pairing was certainly a factor affecting the pollen fertility or seed set in F1 hybrids, but it was not the most important. The positive correlation was generally found between pollen fertility and seed set of F1 hybrids. The L. persicum accession with relatively high interfertility with L. temulentum was supposed to be derived from natural hybridization between L. temulentum and L. persicum. The degree of cytogenetic differentiation between L. temulentum and L. persicum existed because of lower chromosomal pairing, pollen fertility and seed set, but their F1 hybrids were partially fertile.

Chromosome Pairing↗

Atypical teratoid/rhabdoid tumour with leptomeningeal dissemination in an adult.

A 22-year-old man presented with a rare case of atypical teratoid/rhabdoid tumour (AT/RT). Magnetic resonance imaging showed a left cerebellar mass with leptomeningeal dissemination. Partial resection was performed. Histological examination revealed AT/RT. Postoperatively, whole neuraxis and local irradiation were performed. Three-drug chemotherapy with ifosfamide, cisplatin, and etoposide, and adjuvant intrathecal administration of methotrexate were repeated. Near complete response was achieved, and no tumour recurrence/progression has been noticed during the follow up of 24 months. Intensive radiochemotherapy can successfully control AT/RT, even with leptomeningeal dissemination.

Adult↗

Stereotactic radiosurgery for nodular dissemination of anaplastic ependymoma.

Dissemination of primary intracranial ependymoma occurs in 10% of all cases and is difficult to treat, so this may be one of the major reasons for the poor prognosis. Two patients with nodular dissemination of anaplastic ependymoma were treated with repeated stereotactic radiosurgery using the gamma knife (GK), resulting in tumour control over 21 months. GK radiosurgery is a safe and effective treatment option for providing good local control in patients with nodular dissemination of ependymoma.

Adolescent↗

Routine clinical adoption of magnetic resonance imaging was associated with better outcome after surgery in elderly patients with a malignant astrocytic tumour: a retrospective review.

BACKGROUND: There is controversy about extensive surgical treatment for a malignant astrocytic tumour in more elderly patients who may have poorer outcomes and higher complication rates. This retrospective study investigated outcome in elderly patients with malignant astrocytic tumour before and after the adoption of routine clinical use of magnetic resonance (MR) imaging. METHODS: During 1982 through 1999, 88 patients with malignant astrocytic tumour aged 60 years or over were treated in our institute. Thirty-seven patients had an anaplastic astrocytoma and 51 had a glioblastoma. Thirty-seven patients treated from 1982 to 1988 did not have pre-operative evaluation by MR imaging (Group A), 26 patients treated from 1989 to 1995 had preoperative MR imaging evaluation (Group B), and 25 patients treated after 1996 underwent preoperative MR imaging with functional brain mapping and intra-operative navigation system monitoring (Group C). FINDINGS: The median survival time was 8.8 months in Group A, 12.7 months in Group B, and 17.6 months in Group C. Patients with glioblastoma in Group B (11.7 months, n = 15) and Group C (16.0 months, n = 19) had significantly longer median survival time than in Group A (6 months, n = 17) (P = 0.0054 between Groups A and B, P = 0.0024 between Groups A and C). Better preoperative performance status, more thorough surgical resection, and better performance status after the initial treatment was obtained after the introduction of MR imaging, and patients with the optimal indicators showed significantly longer survival time compared with the patients without these factors. INTERPRETATION: Pre-operative MR imaging may contribute to longer survival time by providing an earlier diagnosis in patients with better performance status, by allowing more thorough surgical resection, and resulting in better performance status after the treatment.

Aged↗

Randomized clinical trial comparing level II and level III axillary node dissection in addition to mastectomy for breast cancer.

BACKGROUND: In addition to mastectomy, level II and level III axillary node dissection procedures are performed widely in Japan. A randomized clinical trial was performed to determine which procedure was more effective. METHODS: One group of women had resection of the pectoralis minor muscle and dissection of level I, II and III axillary lymph nodes (level III dissection). In a second group, the pectoralis minor muscle was left intact and level III axillary lymph node dissection was not performed (level II dissection). A total of 1209 women with stage II breast cancer were enrolled in the study and randomly assigned to one of the two groups. RESULTS: The 10-year cumulative survival rate was 86.6 per cent after level II and 85.7 per cent after level III axillary dissection (hazard ratio (HR) 1.02; P = 0.931, log rank test). The 10-year disease-free survival rate was 73.3 and 77.8 per cent respectively (HR 0.94, P = 0.666). Overall survival and disease-free survival rates in the two groups were similar after both procedures. The duration of surgery was significantly shorter (P < 0.001) and blood loss was significantly less (P = 0.001) after level II dissection. In a survey of patients' symptoms on follow-up, no significant differences were found between the two procedures. CONCLUSION: The addition of pectoralis minor muscle resection and level III axillary lymph node dissection to mastectomy for stage II breast cancer did not improve overall or disease-free survival rates.

Adult↗

Non-transcallosal ipsilateral area 3b responses to median nerve stimulus.

We report two patients with left hemisphere lesions who had no normal left hemispheric responses to right median nerve stimulus on magnetoencephalography but displayed right area 3b responses. One patient had suffered a severe left hemispheric contusion and the other left hemispheric infarction. Equivalent current dipoles of these ipsilateral responses were detected on the central sulcus adjacent to the location of the N20m response to left median nerve stimulus. The somatosensory afferent pathway from the hand may extend directly to the ipsilateral area 3b without following the transcallosal pathway in at least part of the population.

Adult↗

Use of intraoperative dynamic infrared imaging with detection wavelength of 7-14 microm in the surgical obliteration of spinal arteriovenous fistula: case report and technical considerations.

BACKGROUND AND OBJECTIVE: Although improvements of spatial and temporal resolution in infrared (IR) imaging have enabled intraoperative real-time acquisition of physiological and pathological information on living organs, the imaging qualities of anatomical delineation of blood vessels and functional delineation of blood flow were insufficient to serve as visual monitoring. The main reason was partly due to the lack of an appropriate IR detection IR band (formerly 3 - 5 micro m), and the broad dynamic range in previous modalities. METHODS: To make a good contrast between blood vessels and surrounding tissues, the detection wavelength was shifted to the long-wave (7 - 14 micro m) part of IR spectrum, which includes the peak IR wave from living tissue (9 - 10 micro m), and the dynamic range was confined to +/- 10 degrees C around 35 degrees C. The novel camera system (IRIS IV infrared imaging system) was used for the visual monitoring of blood flow during the obliteration of a spinal perimedullary arteriovenous fistula at Th 7 in 71-year-old male patient. The temperature resolution of camera was 0.15 degrees C, with its intensity resolution of 16 bit (320 x 240 pixels), and data were stored at a rate of 30 frames/second. High-quality delineation of blood vessels and blood flow was obtained all through the procedure without use of cold saline, which was an inevitable procedure to make contrast in the previously used thermography. However, the occasional use of an air blower was helpful to achieve adequate images in the deep and narrow area of the surgical field. The amount of shunt flow reduction was visualized by the intensity in the acquired imaging, which was also confirmed later by digital subtraction angiography. CONCLUSION: From the present experience, it is considered that this type of imaging may be able to substitute intraoperative blood vessel and blood flow monitoring in spinal and other neurosurgical disorders.

Aged↗

Combined three-dimensional anisotropy contrast imaging and magnetoencephalography guidance to preserve visual function in a patient with an occipital lobe tumor.

OBJECTIVE: Three-dimensional anisotropy contrast (3-DAC) magnetic resonance imaging and magnetoencephalography (MEG) of visually evoked magnetic fields (VEFs) were used to accurately localize the optic radiation and primary visual cortex before surgery for an occipital tumor. PATIENT AND METHODS: A 26-year-old male presented with an occipital lobe tumor located intrinsically underneath the right calcarine fissure. 3-DAC imaging showed that the right optic radiation was located along the superior and lateral surfaces of the lesion. Mapping of the VEFs demonstrated that the primary visual cortex was located superior and lateral to the lesion. The lesion was totally resected via an infero-medial cortical incision using a frameless stereotactic system. Histopathology indicated a pilocytic astrocytoma. No visual deficit was found before or after surgery. CONCLUSION: Combined 3-DAC imaging and MEG can provide essential information about the optic radiation and primary visual cortex for planning the surgical treatment of occipital lobe tumors.

Adult↗

Usefulness of constructive interference in steady state (CISS) imaging for the diagnosis and treatment of a large extradural spinal arachnoid cyst.

We present a rare case of a symptomatic large extradural arachnoid cyst extending from the lower thoracic to sacral region in a 12-year-old boy, who presented with the signs and symptoms of spinal cord compression over 4 years. Since the pedicle of the cyst could not be delineated using conventional magnetic resonance imaging (MRI), cine-mode MRI, and computed tomography scan, partial resection of the cyst was initially performed, which significantly improved motor function. After the first operation, a single pedicle was clearly demonstrated by 3D constructive interference in steady state (CISS) MRI. Thus, additional surgery aimed at closing the dural defect was performed to prevent future enlargement of the cyst. The operative findings were consistent with those of 3D CISS imaging. Clinical and radiological features of this lesion are discussed, focusing on the usefulness of 3D CISS MRI for preoperative evaluation, and especially for delineating the pedicle in cases of large extradural spinal arachnoid cysts.

Arachnoid Cysts↗