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T Nose

Publications and source records attributed to T Nose.

At least 163 records · Page 9Linked to original sources
PubMed1996

Chymotrypsin inhibition induced by side chain-side chain intramolecular CH/pi interaction in D-Thr-L-Phe benzylamide.

The dipeptide benzyl amide H-D-Thr-Phe-NH-CH2-C6H5 was found to inhibit chymotrypsin strongly (K1 = 4.5 x 10(-6) M) in a competitive manner. When a series of phenyl amides H-D-Thr-Phe-NH-(CH2)n-C6H5 (n = 0-4) were tested, inhibitory potency peaked at n = 1 (benzyl amide). Incorporation of a methyl group into the benzyl methylene resulted in formation of stereoisomers, H-D-Thr-Phe-NH-(R or S)-CH(CH3)-C6H5, with considerably different inhibitory potencies. The R-isomer was as active as the benzyl amide, while the S-isomer was about 30-fold less active than the benzyl amide. Furthermore, when a fluorine atom was introduced into the para-position of the amide-benzyl group, the resulting H-D-Thr-Phe-NH-CH2-C6H4(p-F) showed considerably enhanced inhibitory activity (about 5-fold, K1 = 9.1 x 10(-7) M). In conformational analysis by 400 mHz 1H-NMR, all dipeptides having D-Thr-Phe backbone structure showed large upfield shifts of D-Thr-beta OH (shifts in ppm, 0.09-0.17), D-Thr-beta CH (0.23-0.32), and D-Thr-gamma CH3 (0.38-0.53), indicating the presence of shielding effects from the benzene ring. In addition, NOE enhancements between the D-Thr-gamma CH3 and Phe-phenyl groups were evidenced by measurements of two-dimensional NOESY spectra and NOE difference spectra. These observations demonstrated the spatial proximity of these side chains, which is due to side chain-side chain CH/pi interaction. All these results support the idea that the amide-benzyl group binds at the chymotrypsin S1 site, while the hydrophobic core with CH/pi interaction binds at the S2 or S1' site.

Chymotrypsin↗
PubMed1996

Reversible affinity labeling of opioid receptors via disulfide bonding: discriminative labeling of mu and delta subtypes by chemically activated thiol-containing enkephalin analogs.

The 3-nitro-2-pyridinesulfenyl (Npys) group bound to a mercapto group is a highly activated electrophilic reagent, which only reacts with a free mercapto group to form a disulfide bond via the thiol-disulfide exchange reaction. We incorporated the Npys group into enkephalin analogs to affinity label mu and delta opioid receptors. When rat brain membranes were incubated with [D-Ala2,Leu(CH2SNpys)5]enkephalin, and assayed for the inhibition of binding of DAGO and DSLET enkephalin analogs to opioid receptors, the number of receptors decreased sharply, depending upon the concentration of this SNpys-containing enkephalin. It was found that this enkephalin analog occupies mu receptors highly specifically (EC50 = 51 nM) and almost 100 times more selectively than delta receptors. In contrast, [D-Ala2,Leu5]enkephalyl-Cys(Npys)6 attached covalently to delta receptors (EC50 = 34 nM) about 150 times more selectively than to mu receptors. Although N-ethylmaleimide also inhibited the binding of DAGO and DSLET, four to six orders of magnitude higher concentrations were required as compared to SNpys-containing enkephalins. When enkephalin-bound rat membranes were treated with dithiothreitol, the loss of receptors was reversed, depending upon the concentration of and incubation time with dithiothreitol. The recovery was much faster (about 1,000 times) for delta receptors than for mu receptors. The present results indicated that both mu and delta receptors in rat brain consist of a free mercapto group near the enkephalin binding site and that SNpys-containing enkephalins can label these mercapto groups discriminatively. The disulfide bond between [D-Ala2,Leu5]enkephalyl-Cys6 and delta receptors appears to be exposed, while that between [D-Ala2,Leu(CH2-SNpys)5] enkephalin and mu receptors is shielded.

Affinity Labels↗
PubMed1996

The effects of 5-hydroxydopamine on salivary flow rates and protein secretion by the submandibular and parotid glands of rats.

The secretory effects of 5-hydroxydopamine (5-OHDA) were tested in Nembutal-anaesthetized adult male Sprague-Dawley rats injected I.V. over a wide range of doses, with and without various autonomic antagonists and Ca2+ channel blockers. Polyacrylamide disc gel (15%) and iso-electric focusing (IEF) electrophoresis by the PhastSystem were used to separate and determine the types of protein in submandibular saliva. Amylase activity of parotid saliva was determined by the blue dextran method. Salivation by the submandibular glands following application of 5-OHDA was completely abolished by both prazosin and propranolol, whereas salivation by the parotid glands was completely abolished by propranolol alone. Following application of 5-OHDA, there was a dose-related increase in flow rates and total output of protein, but not in the protein concentration and amylase activity, from both salivary glands. The effect of 5-OHDA on submandibular saliva was significantly reduced by alpha-adrenoceptor blockers, but not by beta-adrenoceptor and cholinergic blockers, nor by any Ca2+ channel blocker. The effect of 5-OHDA on the parotid gland was not significantly altered by atropine and phentolamine. However, after pretreatment with reserpine, a 95% reduction was observed in the salivation from the submandibular gland. This implies that 5-OHDA is mostly acting indirectly via release of noradrenaline. The proteins in submandibular saliva following treatment with 5-OHDA alone or 5-OHDA in combination with beta-adrenoceptor blockers were mainly of the alpha-type, whereas after treatment with 5-OHDA in combination with alpha-adrenoceptor blockers they were of the beta-type. The alpha-type was found in saliva after treatment with each of three Ca2+ channel blockers.

Adrenergic alpha-Antagonists↗
PubMed1996

Application of thermosensitive polymers as a new embolic material for intravascular neurosurgery.

Application of thermosensitive polymers as an embolic material for intravascular neurosurgery was investigated. We intended to use thermosensitive polymers to occlude vessels by precipitation in response to body temperature. Copolymers of N-isopropylacrylamide (NIPAM) and N-n-propylacrylamide (NPAM) were selected as thermosensitive polymers. To determine the optimal lower critical soluble temperature (LCST) for the embolic material, we developed an in vitro flow model. In this study the copolymers with an LCST of 24-26 degrees C showed appropriate precipitation. To prove the occlusion of vessels in vivo, we injected the copolymers into a rabbit kidney through a microcatheter. The extent of embolization was judged by angiography and histological examination. An acute toxicity test of the copolymer of NIPAM and NPAM was performed in comparison with that of the NIPAM monomer. The copolymer used in this paper showed no acute toxicity in mice. Water solubility, non-adhesiveness, and non-toxicity are the advantages of the use of thermosensitive polymers as an embolic material. By changing the LCST, various embolic materials can be designed. Based on our results, we believe that the application of thermosensitive polymers as a new embolic material is very promising.

Acrylamides↗
PubMed1996

Focal residual contrast media in the kidney 24 hours after angiography.

PURPOSE: To examine the relationship between focal renal cortical retention (FRCR) and contrast-associated nephropathy (CAN). MATERIAL AND METHODS: We investigated the incidence of both phenomena in 105 patients. CAN was defined as an increase in the creatinine level > 0.3 mg/dl and > 20% on days 1, 3, or 7. We compared predisposing factors for FRCR and CAN. Serum creatinine and blood urea nitrogen (BUN) for renal function were determined on the morning of the day of the angiography. The BUN/creatinine ratio was used as an indicator of the degree of hydration. RESULTS: FRCR was demonstrated in 17 patients (16%) by delayed CT 24 h after angiography, and CAN was found in 16 patients (15%). No significant relationship between CAN and FRCR was found. We found a correlation between high total volumes of contrast and FRCR. Advanced age, high blood urea nitrogen, high creatinine, and dehydration were risk factors for CAN. CONCLUSION: Delayed CT showed a higher incidence of injury to the renal parenchyma than previously detected by conventional radiography.

Angiography↗
PubMed1996

Magnetic resonance imaging of brain death.

Fifteen patients with clinical diagnosis of brain death were examined by magnetic resonance (MR) imaging. Aortography with intraarterial digital subtraction angiography (IADSA) was also performed in nine patients. MR imaging indications of the flow void phenomenon were evaluated in the cavernous portion of internal carotid artery (ICA) and the middle or anterior cerebral artery, and compared with the IADSA findings. The relative intensities of gray and white matters were also measured. MR imaging showed that flow voids were absent in the ICA in all eight patients in whom non-filling was confirmed by IADSA. In one patient, IADSA demonstrated intracranial flow despite the diagnosis of brain death and the flow void pattern was normal. Serial MR imaging showed disappearance or abnormality of flow voids after brain death in six patients and absence before brain death in one. Spotty flow voids became visible in the unilateral ICA of one case after brain death. Partial residual flow voids may be caused by to-and-fro blood movement which was demonstrated by transcranial Doppler sonography. The normal flow void pattern was seen in none of these patients, therefore absence of flow voids indicates cessation of intracranial blood flow. Proton density and T2-weighted MR images showed dissociated intensity changes between white and gray matters, which were thought to be characteristic of brain death. In conclusion, MR imaging can achieve non-invasive diagnosis of the non-filling phenomenon in patients with brain death.

Adult↗
PubMed1996

Posterior fusion for odontoid fracture in an infant--case report.

A 2-year-3-month-old girl presented with a rare displaced odontoid fracture. She was managed nonoperatively by manipulation followed by 3-month extracorporeal fixation with a halo brace. However, lateral radiography revealed recurrent dislocation at the base of the odontoid process. Magnetic resonance imaging demonstrated a "synchondrotic slip." She therefore underwent posterior wiring with iliac bone grafting to prevent pseudoarthrosis. The odontoid process had fused to the axis at 4 months postoperatively. Surgical management should be considered as a treatment method for pediatric odontoid fracture because of the difficulties in maintaining long-term immobilization and confirming the union.

Child, Preschool↗
PubMed1996

Acoustic neurinoma with a large organized hematoma--case report.

A 66-year-old female presented with a large organized hematoma within an acoustic neurinoma. She had suffered from diminished hearing for 20 years and had headache 1 week before presentation. Computed tomography demonstrated an inhomogeneously high density cerebellopontine angle mass, and magnetic resonance imaging showed a mass with heterogeneous intensity and gadolinium-diethylenetriaminepenta-acetic acid enhancement of only the peripheral surface of the mass and the inner parts of the internal auditory meatus. At operation the majority of the mass was soft and feature-less with a firm capsule, and a yellowish soft tumor was removed from the perimeatal area. Histological examination showed the mass was an acoustic neurinoma with a large organized hematoma. Extensive hemorrhage from an abnormal vascularity in the tumor had repeated followed by granulomatous organization.

Aged↗
PubMed1996

Expression of N-ras gene in gliomas.

Expression of N-ras gene was examined by northern blot analysis in two cases of astrocytoma (grade II), four cases of glioblastoma multiforme (six samples including two recurrent tumors), and normal brain tissues. Expression of N-ras gene was only found in the two recurrent glioblastoma multiforme samples. Southern blot analysis found no significant difference in copy numbers of N-ras gene in pre- and post-recurrence samples. The histological diagnosis of the two recurrent tumors was glioblastoma multiforme at both first recurrent presentation. However, the tumors had progressed during recurrence, because of worsened histological findings, such as increased cellularity, pleomorphism, and vascularity. These tumors recurred at very short intervals. Enhanced expression of N-ras gene by disorder of transcription may be a factor in the progression of glioblastoma multiforme.

Astrocytoma↗
PubMed1996

Brainstem arteriovenous malformation with a pedicle aneurysm treated by endovascular surgery and proton-beam radiosurgery--case report.

A 39-year-old male presented with a small pontine hemorrhage and subarachnoid hemorrhage. Angiography showed a small left pontine arteriovenous malformation (AVM) associated with a small aneurysm on the pedicle feeding the AVM. The pedicle aneurysm was occluded by microcoils. The AVM was then treated by proton-beam radiosurgery. Follow-up angiography 2 years later revealed that the AVM had disappeared completely without neurological deficit. The combination of embolization and proton-beam radiosurgery was curative in this patient with a pontine AVM associated with an aneurysm on the feeding artery, showing that these techniques can be used to treat inoperable vascular lesions safely.

Adult↗
PubMed1996

Cerebral metastasis of parathyroid carcinoma.

A 54-year-old female presented with a cerebral metastasis of functioning parathyroid carcinoma in the right occipital lobe. After surgical removal of the metastatic tumor, her symptoms of left hemianopsia and hypercalcemia improved. Surgical treatment should be considered in a case of brain metastasis of parathyroid carcinoma associated with secondary hyperparathyroidism to prevent metabolic complications and reduce the mass of the tumor.

Brain Neoplasms↗
PubMed1996

Surveillance system of infectious diseases in Japan.

The surveillance system of infectious disease in Japan started in 1981 and has been providing useful epidemiological information on 27 communicable diseases. The system consists of medical institutions (fixed monitoring stations), institutions of hygienic sciences, health centers, local governments and the ministry of health and welfare. There are two types of information about infectious diseases. One is clinical reports of incidence cases from medical institutions, and the other is laboratory information about etiologic agents. Between health centers, local governments and the department of statistics and information in the ministry of health and welfare, information is transmitted through the on-line network. Collected information is analyzed and submitted by both local and central committees of analysis. From the epidemiological point of view, quality control of the data and integration of other sources of data would be the next goal of the system.

Databases, Factual↗
PubMed1996

Induction of human autologous cytotoxic T lymphocytes against minced tissues of glioblastoma multiforme.

The authors induced autologous cytotoxic T lymphocytes (CTLs) directly from peripheral blood lymphocytes by preparing a coculture of minced tissue fragments of glioblastoma multiforme (GBM) with interleukins-1, -2, -4, and -6 and interferon-gamma in RHAM alpha medium containing 5% autologous plasma for 2 weeks. At the end of this period, the frequencies of CD3+, CD4+, CD8+, and CD16+ lymphocytes were 95% to 99%, 40% to 62%, 37% to 38%, and 0.2%, respectively. The lymphocytes killed 82% to 100% of the GBM cells within 48 hours at an effector-to-target cell ratio of 1.67, whereas in a separate coculture, autologous lymphokine-activated killer (LAK) cells killed only 33% of GBM cells under the same conditions. The lymphocytes showed no cytotoxicity against LAK-sensitive Daudi cells, natural killer-sensitive K562 cells or autologous fibroblasts grown from the brain tumor, although they did show slight cytotoxicities against allogeneic GBM cell lines. These results lead the authors to suggest that the lymphocyte population contains specific CTLs for autologous brain tumor cells and that these CTLs could be effective in adoptive immunotherapy to combat brain tumor.

Adult↗
PubMed1996

Spinal extradural meningeal cyst. Case report.

The case of a 30-year-old man with a spinal extradural meningeal cyst in the thoracolumbar region is reported. Operative findings revealed a dural defect that allowed communication between the extradural cyst cavity and the subarachnoid space. Application of the Valsalva maneuver made the cerebrospinal fluid flow into the cyst cavity; however, reverse flow did not occur. These findings indicate that a valvelike mechanism developed in the enlarging cyst. Surgical resection of the cyst wall and closure of the dural defect provided a favorable result.

Adult↗
PubMed1996

Late local recurrence after radiotherapy for tongue and early glottic carcinoma.

BACKGROUND/AIM: Late local recurrence after radiotherapy for tongue and early glottic carcinoma is rarely discussed. In the head and neck cancer, approximately 90% of local recurrence occurred within 2 years after radiotherapy. However, we found that late local recurrence after radiotherapy for glottic cancer was not rare. Our aim was to evaluate the late local recurrence after radiotherapy for early glottic and tongue cancer. PATIENTS AND METHODS: From 1967 through 1982, 633 patients with tongue carcinoma and 330 patients with early (T1T2N0) glottic carcinomas were treated at the Department of Radiology, Osaka University Hospital. Of these 821 patients, 329 patients with tongue carcinoma and 221 patients with early glottic carcinoma survived at 5 years after radiotherapy without local recurrence. For tongue carcinoma, patients were divided by T category. For early glottic carcinoma, patients were divided by the tumor response at 40 Gy. RESULTS: Late local recurrence occurred in 23 of 329 patients (7%) with tongue carcinoma, and in 9 of 221 (4%) with early glottic carcinoma. For tongue carcinoma, late recurrence occurred in 19 of 249 patients (8%) in stage I and II, and 4 of 80 patients (5%) in stage III and IV. For glottic carcinoma, late recurrence occurred in 8 of 137 patients (6%) with tumor clearance at 40 Gy and 1 of 63 patients (2%) with tumor persistence at 40 Gy. The incidence of double cancer was also evaluated. Of 329 5-year survivors with tongue carcinoma, 39 patients (12%) had another malignancy, and 26 patients of 221 5-year survivors with early glottic carcinoma (12%) had also another malignancy. Of 39 double primaries of tongue carcinoma, 10 patients (26%) had head and neck malignancies, and none of 26 double primaries of early glottic carcinoma. CONCLUSION: Late local recurrence was not rare in tongue and early glottic cancer. Poor prognostic group showed lower incidence of late recurrence than good prognostic group. This result suggests that secondary tumor at the same site of primary tumor is late local recurrence.

Carcinoma↗
PubMed1996

[Perioperative fractionated high dose rate brachytherapy in bone and soft-tissue tumors].

The 13 lesions of 11 patients with bone and soft-tissue tumors (four primary and nine recurrent lesions) were treated with surgery and postoperative fractionated high dose rate (HDR) brachytherapy started on the 6-7th day after surgery. The total dose was 40-50 Gy/7-10 fr/6-7d(bid) at 5 mm from the source. Local control was achieved in eight of 13 lesions (62%). Four of the five uncontrolled lesions had macroscopic residual tumor after the surgery. There was one peripheral nerve damage as a side effect. This study indicates that the use of perioperative fractionated HDR brachytherapy is feasible and well tolerated.

Adolescent↗
PubMed1996

[Preoperative chemoradiation therapy for lower rectal cancer].

To identify appropriate candidates with rectal cancer for preoperative chemoradiation therapy, the local recurrence rate and clinicopathological characteristics of 232 patients with rectal cancer undergoing curative resection in our department were investigated. The local recurrence rates were 3.8%, 10.8% and 16.5% in the Rs, Ra and Rb lesions, respectively. Regarding lower (Rb) rectal cancer, depth of lesion (> a1) and nodal metastasis consisted of high factors for local recurrence. Basing on these results, entry criteria for preoperative chemoradiation therapy were established, and concurrent chemoradiation therapy with fluorouracil and cisplatin was delivered preoperatively in 9 primary cases of locally advanced rectal cancer and 3 cases with local recurrence. A partial response was obtained in 7 of 12 cases with a response rate of 58%, size-reduction of the distant metastatic lesions was found in 2 cases, and clinical symptoms were improved in all cases. The histological responses of the 6 resected cases were Grade 2 in 2 cases and Grade 1b in 4 cases. The toxicities of this chemoradiation regimen were well tolerable. As a postoperative complication, infection of the perineal wound was most frequent. Preoperative chemoradiation therapy with the present regimen would be a useful adjuvant treatment for advanced lower rectal cancer.

Aged↗