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T Nitta

Publications and source records attributed to T Nitta.

At least 91 records · Page 5Linked to original sources
PubMed1995

[A clinicopathological study of 16 cases with optico-hypothalamic glioma].

Although gliomas of the optic nerve pathways, optico-hypothalamic gliomas, have been considered to be benign neoplasms, some recurrent, malignant gliomas especially at the optic chiasm and hypothalamus have also been reported. It is crucial to know the factors that influence the prognosis of these tumor entities. In order to address this question, we analyzed 16 cases of optico-hypothalamic gliomas treated in our institute with emphasis especially upon the age, location of tumor, histological subtype and treatment modality. Eleven patients younger than 20 years and five older than 20 years were included in this study. In two patients the gliomas were accompanied by neurofibromatosis 1. The male to female ratio was 9:7. Anatomical locations of the tumors were categorized from T1 to T4, and visual symptoms were V0 to V4. Patients with tumors located within the optic nerve, chiasm (T1-3) mainly presented visual symptoms, but those with hypothalamus (T4) showed neuroendocrine signs but not visual ones. Twelve out of 16 cases represented isodense mass lesions on plain CT scans, which were homogenously enhanced by contrast media. Among 15 cases verified pathologically, 10 cases were pilocytic astrocytomas, 4 were astrocytomas and one was anaplastic astrocytoma. The survival rate was measured by Kaplan-Meier method and overall 5-year survival rate was 70.5%. Patients younger than 20 years could survive longer than those older than 20 years (87.5% and 40.0% respectively).(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1995

[A clinicopathological study of nine cases of midbrain glioma].

The majority of brain stem gliomas tend to occur during childhood and arise in the pons. The prognosis of these typical pontine gliomas is almost invariably bad. In contrast, there exists a group of benign brain stem gliomas, mostly arising from the midbrain and are amenable to surgical resection. They are often low-grade astrocytomas and are associated with better prognosis. We summarized nine cases of intrinsic midbrain gliomas and their clinical behavior was analyzed by radioimagings and histopathological examination. They were classified from CT images according to Stroink et al. and from anatomic staging by Epstein. The result showed that 5 in 9 cases were so called, "focal midbrain gliomas". That is to say, the tumor arose from the tectal plate or the tegmentum of the mesencephalon and expanded dorsally, but did not invade the surrounding neural tissues. Three focal midbrain gliomas in childhood were well demarcated and surgically resectable. Histologically, tumors were astrocytomas and were associated with favorable prognosis. However, two focal midbrain gliomas in adulthood were anaplastic astrocytoma and the prognosis was poor, even though they appeared similar shown on radioimaging study. The overall survival rate of patients with midbrain glioma was longer than that of patients with glioma in the cerebral hemisphere. From these results, it was concluded that a specific group of intrinsic, focal midbrain gliomas can be classified into pediatric benign gliomas and adolescent malignant ones. A further number of cases should be studied to clarify this hypothesis.

Adolescent↗
PubMed1995

[Perinodal cryomodification for supraventricular tachycardia].

The perinodal cryomodification procedure ablates the surrounding tissue of atrioventricular node, as a consequence, eliminates atrioventricular nodal reentrant tachycardia (AVNRT) and reduces the ventricular response during atrial fibrillation. We performed the procedure in 4 patients: 2 patients with AVNRT, 1 patient with atrioventricular reciprocating tachycardia utilizing a left side accessory pathway and atrioventricular node dual pathways, and 1 patient with tachycardic atrial fibrillation. The concomitant procedures include a closure of atrial septal defect and a mitral valve replacement. All the patients survived the procedure and cured the tachycardia. Post operative electrophysiological studies showed that the retrograde conduction over the atrioventricular node was eliminated while the antegrade conduction was preserved in the patients with atrioventricular node dual pathways. The perinodal cryomodification is a safe and effective procedure to cure the tachycardia, particularly in the patients with a structural heart disease.

Adult↗
PubMed1995

[A clinical study of 21 patients with neurofibromatosis I and II].

Neurofibromatosis (NF) 2, associated with bilateral acoustic neurinomas has been shown to be an entity distinct from NF 1, since their chromosomal abnormalities are completely different. NF 2 has a very low occurrence rate, but would be a terrible disease by its high prevalence of offsprings. In addition, compared to the majority of unilateral, nonfamiliar neurinoma, acoustic neurinomas of NF 2 have been shown to be refractory to treatments. Therefore, it is crucial to know the clinical characteristics of patients with NF 2. In this study, we analyzed 14 cases of NF 2 and 7 cases of NF 1 in whom brain tumors are main symptoms. Brain tumors associated with NF 1 were five neurinomas, two gliomas and a meningioma. The mean age of NF 1 patients accompanied with brain tumors was 37.6 years old, younger than the overall age of NF 1 patients. In patients with NF 2 there was often association with cranial, and spinal neurinomas and meningiomas. NF 2 especially, in younger patients was accompanied with multiple spinal neurinomas. Twenty acoustic neurinomas in 14 NF 2 patients were treated by surgery. Operative results showed that total resection was achieved in only 5 cases, 13 were subtotally and 2 were partially resected. Hearing preservation was attained in only three cases. In addition, all but two patients were complicated with postoperative facial palsy. From this analysis, it is clear that NF 2-associated acoustic neurinomas are not responsive to surgical intervention. We also reviewed genetical problems briefly.

Adult↗
PubMed1995

[Sequential coronary artery bypass grafting utilizing the internal thoracic and gastroepiploic artery as in situ grafts].

36 consecutive patients (male:female = 33:3, mean age 57.3) underwent sequential coronary artery bypass grafting (CABG) utilizing the left internal thoracic artery (LITA, n = 30), right gastroepiploic artery (RGEA, n = 8) as in situ grafts. Two patients received sequential bypass grafting with both grafts simultaneously. No right internal thoracic arteries were used except for one as a free nonsequential graft. Taking into account the adjunctive venous anastomoses and the arterial nonsequential anastomoses, there were 3.5 anastomoses per patients. Proxymal side-to-side anastomosis of LITAs were all constructed on the diagonal branches except for one on the proxymal Left Anterior Descending Coronary Artery (LAD), whereas that of the RGEAs were on the proxymal Right Coronary Artery (RCA) (2), distal RCA (6) or distal circumflex (1). Distal end-to-side anastomoses of LITAs were all on the LAD, and those of the RGEAs were on the distal RCA (3) or distal circumflex artery (5). Proxymal side-to-side anastomoses were always performed first, allowing us to assess the distal flow through the graft before we anastomose it to the distal branch. We routinely obtain a preoperative angiogram of the arterial grafts, which enable us to fully assess the suitability of the arteries as in situ grafts. There were no perioperative deaths, nor perioperative myocardial infarctions, however, two patients died of extracardiac causes at 42 and 68 days after operation respectively. For the thirty four survivors, followup was complete (4-49 months, average 12.3 months). One still had angina of Canadian Cardiovascular Society Classification (CCSC) class 2, and 33 were free of angina.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1994

Selective expression of interleukin-10 gene within glioblastoma multiforme.

Little information exists regarding which glioma cells are able to escape immune system detection and progress within the host. In order to elucidate some of the mediators which facilitate the growth and spread of glioma cells, the expression of cytokines, TNF-alpha, IL-6, gamma-IFN, IL-10, and GM-CSF, within 12 human glioma specimens was investigated by the polymerase chain reaction. The twelve patients with malignant glioma were categorized into a localized (n = 4) and an invasive glioma (n = 8) groups, mostly glioblastoma multiforme, based upon the CT and MRI scans. We examined the correlation between specific cytokine gene expression and the clinical category of each patient. The results showed that while IL-10 mRNA transcripts were expressed in most of the tumors from the invasive glioma group (7/8), they were not expressed in tumors from the localized group. On the other hand, gamma-IFN gene expression was more frequent in tumors from the localized group (3/4 vs 1/8 from the invasive group). The mRNA transcripts of IL-6 and GM-CSF were more frequently expressed in tumors from the localized group. No consistent pattern was seen in TNF-alpha gene expression between the two groups. Among the five cytokines studied, IL-10 mRNA was selectively expressed within invasive gliomas compared to less malignant, localized glioma group. Our results demonstrate specific cytokine mRNA profiles in glioma patients, which might have prognostic significance for immunotherapy.

Adult↗
PubMed1994

Shared amino acid sequences in the ND beta N and N alpha regions of the T cell receptors of tumor-infiltrating lymphocytes within malignant glioma.

The purpose of this study was to assess the V-(D)-J junctional region of the T cell receptor (TCR), the CDR3 region, which is responsible for glioma-specific antigen contact in alpha beta TCR-mediated recognition. We sequenced the TCR alpha and beta chains of V alpha 7, and V beta 13.1 cDNA derived from tumor-infiltrating lymphocytes (TIL) of 12 glioma patients and also the corresponding clones from the patients' peripheral blood lymphocytes (PBL). A shared V beta 13.1 DJ sequence of the CDR3 region, ND beta N, was demonstrated in 49 of 66 V beta 13.1+ clones (74.2%) from the glioma TIL, whereas only 4 of 33 clones (12.1%) were observed in the V beta 13.1+ clones from the PBL (p < 0.001). A common VDJ sequence, FCASS (V beta 13.1)-YRLPWGTSDS (ND beta N)-GELFF (J beta 2.2), was observed not only in the gliomas from each patient, but also among all the patients with a preference for V beta 13.1. In contrast, the amino acid sequences of the V beta 13.1+ PBL clones were diverse and random. Next, we sequenced subclones from other V beta subfamilies randomly selected to compare their VDJ region rearrangements (V beta 3 and V beta 5.1). In contrast to V beta 13.1, the amino acid sequences of these junctional regions were completely different in these subclones. The V-J junctional region of the alpha chain is dominated by a few clones in some patients, and no shared amino acid sequences were detected in the TCR V alpha junctional region. However, in the N alpha region of the V alpha 7-bearing TIL clones, arginine was used in 27 of 44 clones (61.4%) compared to only 3 of 12 clones from the PBL (p < 0.05). These results are consistent with the hypothesis that a clonal expansion/accumulation of glioma lineage-specific T cells occurred in vivo at the tumor site and that these T cells may be recognizing glioma-specific antigens.

Adult↗
PubMed1994

Association of malignant glioma with the human leukocyte antigen, HLA-A24(9).

Many immune responses are controlled by genes of the major histocompatibility complex (MHC). In humans these include the loci encoding the HLA-A, -B, -C, -DR, -DQ, and -DP antigens, and many diseases have been linked with these. However, little information is available about any connection between malignant tumors and HLA. In this study the possible association of HLA-A, -B, -C and -DR specificities with susceptibilities to malignant glioma was investigated in 42 patients with malignant glioma and 42 controls with non-glial intracranial tumors using the Terasaki-NIH standard method. The data were also compared with those of the 11th International HLA Workshop. The result showed that a high frequency of HLA-24(9) was observed in patients with intracranial malignant gliomas, which was not common in other, non-glial patient groups. In animals the MHC acts in defense against virally induced tumors, but until now there has been no evidence that they do so in human gliomas. Our discovery of its association with an HLA antigen is important for understanding the immunogenetic basis of susceptibility to glioma.

Adolescent↗
PubMed1994

Human ventricular tachycardia: precise intraoperative localization with potential distribution mapping.

Electrophysiologically guided operations for ventricular tachycardia (VT) have been directed exclusively by activation time maps. Even with computer-assisted mapping, extensive editing is required, which prolongs the duration of the operation and which may introduce significant error. In contrast, potential distribution maps can be constructed in less than 3 minutes and can be viewed as a movie of developing and receding potentials. In 4 patients undergoing operation for VT, endocardial mapping was performed using form-fitting electrodes containing 160 points. A computerized mapping system, capable of simultaneously recording 256 channels of data, was used to analyze data and to display potential distribution maps sequentially at 1-millisecond intervals as a color movie. A total of eight morphologies of sustained VT were mapped. The mean VT cycle length was 340 +/- 40 milliseconds (range, 274 to 394 milliseconds). In 3 patients with ischemic heart disease, four VT morphologies originated from the subendocardium. All were successfully ablated with cryoablation alone or in conjunction with aneurysmectomy and endocardial resection. A fourth patient with VT secondary to cardiomyopathy had multiple morphologies and received an implantable cardioverter defibrillator. Potential distribution maps correlated well with the concomitant activation time maps. Thus, potential distribution mapping provides a rapid and accurate means of identifying the site of origin of VT facilitating intraoperative mapping in patients undergoing surgical ablation.

Action Potentials↗
PubMed1994

Gas chromatography/mass spectrometric analysis of 24R,25-dihydroxyvitamin D3 using 24R,25-dihydroxy[6,19,19-2H]vitamin D3 as internal standard.

Gas chromatography/mass spectrometric (GC/MS) analysis of 24R,25-dihydroxyvitamin D3 (24,25-(OH)2D3, 1a) in rat serum is examined using 6,19,19-trideuterated derivative (24,25-(OH)2[6,19,19-2H]D3, 1c) as an internal standard. Pyro- and isopyro-24,25-(OH)2D3 (2a and 3a) are synthesized and the structures are determined unambiguously by their spectral data including nuclear overhauser enhancement study of the NMR spectra. The two peaks which appear on the total ion chromatogram of 24,25-cyclic n-butyl boronate-3-trimethylsilyl derivative of 24,25-(OH)2D3 are identified to be those of the pyro and isopyro isomers (2a and 3a) by direct comparison with the synthetic standards. Analysis of the GC/MS spectrum of 24,25-(OH)2[6,19,19-2H]D3 (1c) indicated that the CH3(19) is preferentially eliminated in the fragmentation giving rise to a base peak (M-TMSOH-Me)+. Thus the molecular ion peak, which is about 20% of the base peak, rather than the base peak is used for GC/MS assay of 24,25-(OH)2D3 in serum.

24,25-Dihydroxyvitamin D 3↗
PubMed1994

Expression of tumour necrosis factor-alpha, -beta and interferon-gamma genes within human neuroglial tumour cells and brain specimens.

Expression of cytokine genes, TNF-alpha, TNF-beta and IFN-gamma, in human astroglial cell lines and in fresh brain specimens was studied by PCR. mRNA transcripts of TNF-alpha could be detected in three out of five astrocytomas and neuroblastoma cell lines, and after stimulation with IL-1 beta/IFN-gamma or LPS/IFN-gamma all these cell lines expressed TNF-alpha genes. TNF-beta genes could not be detected in these cell lines. We were able to detect expression of IFN-gamma genes within two astrocytoma cell lines, which interestingly did not show TNF-alpha activity. In addition to the cultured cells, we also examined gene expression of these cytokines within four human malignant astrocytoma specimens, two peritumoral brain and two autopsied normal brains. The results show that tumour and surrounding reactive lesions express TNF-alpha genes (four of six) but not normal brains. The concentration of these cytokines in the supernatant of cultured cells was measured quantitatively by TNF-alpha, -beta or IFN-gamma ELISA. The combined stimulation of these neuroglial cell lines with IL-1 beta and LPS or IFN-gamma, revealed a high level of TNF-alpha activity. This was especially evident with a neuroblastoma cell line. The concentration of TNF-alpha in the supernatant of the IMR32 neuroblastoma cell line increased markedly upon stimulation with IL-1 beta in both a time- and dose-dependent fashion in the presence of LPS or IFN-gamma. Next, we examined expression of IL-1 beta and IFN-gamma genes in the brain specimens. The result shows that four in six tumour and peritumoral regions expressed IFN-gamma genes and one specimen showed IL-beta gene by PCR. From these experiments it is suspected that neuroglial cell-derived TNF-alpha induced by IL-1 beta of IFN-gamma may participate in local immune reactions of the brain in an autocrine and paracrine fashion.

Actins↗
PubMed1994

Phase I study of irinotecan and cisplatin with granulocyte colony-stimulating factor support for advanced non-small-cell lung cancer.

PURPOSE: Since leukopenia was one of the dose-limiting toxicities of the combination of irinotecan (CPT-11) and cisplatin in a previous trial, we conducted a phase I trial to investigate whether support with recombinant human granulocyte colony-stimulating factor (rhG-CSF) would permit further intensification of the CPT-11 dose in combination with a fixed cisplatin dose. PATIENTS AND METHODS: Twenty previously untreated patients with stage IIIB or IV non-small-cell lung cancer (NSCLC) were treated with CPT-11 on days 1, 8, and 15 in combination with cisplatin 80 mg/m2 intravenously on day 1. In addition, rhG-CSF (2 micrograms/kg/d) was administered on days 4 to 21, except on the days of CPT-11 treatment. The starting dose of CPT-11 was 70 mg/m2, and the CPT-11 dose was escalated in 10-mg/m2 increments until the maximum-tolerated dose was reached. RESULTS: Diarrhea was the dose-limiting toxicity at 90 mg/m2. Two of six patients experienced either grade 3 or 4 diarrhea or grade 3 leukopenia during the first course of therapy at this dose level. Modest escalation of the CPT-11 dose from 80 to 90 mg/m2 resulted in a marked increase in the plasma concentration of 7-ethyl-10-hydroxycamptothecin (SN-38). Occurrence of diarrhea was well correlated with the peak plasma concentration (Cmax) of SN-38 (P = .035). There were 10 partial responses (50%) among 20 patients. CONCLUSION: The recommended dose for phase II studies is 80 mg/m2 of CPT-11, and 80 mg/m2 of cisplatin plus rhG-CSF. With the use of rhG-CSF, the CPT-11 dose can be increased 33% above that in the original regimen (60 mg/m2 of CPT-11 and 80 mg/m2 of cisplatin).

Adult↗
PubMed1994

Specific inhibition of c-sis protein synthesis and cell proliferation with antisense oligodeoxynucleotides in human glioma cells.

The protein encoded by c-sis is overexpressed in human neuroglial tumors and has been hypothesized to play an important role in tumorigenesis. To address this issue, we examined the effect of an 18-base pair oligodeoxynucleotide complementary to a sequence starting of ATG initiation codon of mRNA of c-sis upon glioma cell growth. First, we investigated the expression of c-sis within cultured human glioma cell lines and also fresh glioma specimens by using polymerase chain reaction. We could detect messenger ribonucleic acid transcripts of c-sis in three of four glioma cell lines and two of five glioblastoma multiforme specimens. This finding was confirmed by dot-blot hybridization with a specific oligonucleotide probe of c-sis. The antisense oligonucleotides complementary to c-sis messenger ribonucleic acid were efficiently incorporated into A172 cells in vitro, and kinetic studies showed that maximum uptake was seen after 48 hours incubation with antisense oligomers. Exposure of human glioma cell lines to antisense oligodeoxynucleotides targeted against the first initiation codon of c-sis inhibited cell proliferation in a time- and dose-dependent fashion. From flow cytometric analysis with anti-c-sis sera, it was demonstrated that the antisense oligomers specifically block the de novo synthesis of intracellular c-sis protein by glioma cells. In contrast, the corresponding sense oligomers did not inhibit either synthesis of c-sis protein or glioma cell growth. These results clearly support a role of c-sis protein in the proliferation of these human neuroglial tumors and show that inducible protein expression can be blocked by means of synthetic oligonucleotides complementary to a coding exon.

Brain Neoplasms↗
PubMed1994

[Changes in the salivary testosterone level in aged].

Measurement of the level of free testosterone is important in the evaluation of testicular function. Because most of the testosterone in the saliva is in the free form, measurement of the salivary testosterone level is considered to be effective for the evaluation of testicular function. In the present study, a commercial kit was employed to measure the salivary testosterone level, and the change in the salivary testosterone level with age was investigated. The subjects of this study were 76 males, 20-89 years of age, with no endocrinological diseases. The concentration of testosterone in the saliva was measured for each of the subjects, and for 34 of the subjects the concentrations of total testosterone and free testosterone in the serum were also measured at the same time. Standard serum was diluted to have a testosterone concentration of 50 pg/ml, and the results indicated that it was sufficiently possible to measure the salivary testosterone. The coefficient of correlation between the salivary testosterone concentration and the serum total testosterone concentration was 0.479 (p < 0.01), while the coefficient of correlation between the salivary testosterone concentration and the serum free testosterone concentration was 0.732 (p < 0.001). These findings thus indicate that the correlation between the salivary testosterone concentration and the serum free testosterone concentration is better than that between the salivary testosterone concentration and the serum total testosterone concentration. It was also demonstrated that the salivary testosterone concentration decreased significantly with aging after the fifth decade of life. The correlation coefficient for that relationship was -0.606 (p < 0.001), and the change was similar to that seen in the serum free testosterone concentration as a function of aging. The findings suggested that measurement of the salivary testosterone concentration with the commercial kit is useful for the evaluation of testicular function.

Adult↗
PubMed1994

[A 37-year-old man with memory loss, homonymous hemianopsia, and elevation of anti-herpes simplex virus antibody titer].

We report a 37-year-old man who presented memory loss, homonymous right hemianopsia, and elevation of anti-herpes simplex antibody titer. He had an auto accident in January 1992 in that the car he was driving slipped down a 3 m slope; his car was severely damaged, however, he himself was not injured. Shortly after this accident, he went out of his house less often than before, and he noted some difficulty in his vision. He changed his glasses twice, but his vision was unchanged. In July of 1992, he had an onset of difficulty in recent memory and disorientation to time. He also noted diplopia, and difficulty in seeing objects in his right visual field. He was admitted to our hospital on August 26 of the same year. General physical examination was unremarkable. On neurologic examination, he was alert but disoriented to time and place; calculation was also impaired. Mini-mental state examination was 18/30. He had no aphasia, apraxia, or agnosia. He showed a tendency to neglect his left side. Optic fundi and visual acuity were normal; right homonymous hemianopsia was present. Ocular movement was moderately restricted to most of the directions; pupils were isocoric and reacted to light promptly. He complained of diplopia in right gaze, and monocular nystagmus was induced in his right eye upon right lateral gaze. Trigeminal nerves appeared intact. Minimum left facial weakness was present. The remaining of the cranial nerves appeared intact. His gait was wide-based and tandem gait was impossible. Muscle strength was normal as was the muscle tone. Finger to nose and heel to knee tests were done normally.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗