Biomedical subjects
Publications and source records attributed to K Sako.
A case of a 19-year-old woman who had coarctation of the descending aorta associated with an aneurysm of the anterior communicating artery is reported. The aneurysm was successfully clipped during the acute phase of subarachnoid hemorrhage.
A retrospective analysis of 33 cases of maxillary sinus cancer seen at R.P.M.I. between 1970 and 1979 was performed. The age of the patients ranged from 18-88 years, with a median age of 60.3. The male to female ratio was 2:1.3. Twenty-seven (81.8%) of the cases were squamous cell carcinomas. Of the 33 cases, there were no cases in Stage 1, 2 cases in Stage 2, 8 and 23 in Stages 3 and 4, respectively. The 5-year survival among the patients who were available for a long-term follow-up was 36.4% (8 of 22). The 5-year survival was best for Stage 3 disease (75%) and Stage 4, without local and/or distant metastasis (57.14%). No patient with metastasis lived for more than 3 years. While poorer diagnosis could be related to the degree of local involvement and presence of metastasis, it could not be related to site of involvement, previous treatment, histological findings or delay in diagnosis. Correlation of treatment with prognosis is difficult because selection of treatment is based on a variety of factors, including stage of disease and patient acceptance of treatment. Of the 4 patients treated with surgery alone, all 4 survived for 5 years. Of the 8 patients treated with combined surgery and radiation, 4 survived for 5 years and 2 died without evidence of tumor before 2 years. Other treatments were far less successful.
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Changes of local cerebral blood flow (l-CBF) were estimated by autoradiographic techniques in middle cerebral artery occlusion rats given a large dose of (3 mg/kg) dexamethasone. The sensory-motor, parietal, auditory and olfactory cortices showed a significant reduction (greater than 25%) of l-CBF. In MCA occlusion with large dose dexamethasone group, ischemic cortices showed significant reduction from the only MCA occlusion group (highest 36%). There was no significant reduction of l-CBF in the deep structures. The effects of dexamethasone on drains with various pathologies have been studied both clinically and experimentally with many kinds of techniques. These effects are now being reevaluated. Still controversial however, is the mechanism that determines whether dexamethasone has beneficial, non-beneficial, or harmful effect. This study may help us to unravel the mechanism of steroid effects, as well as the relationship between corticosteroid and central nervous system.
This is a retrospective study done in 89 patients who were treated for stage I lingual carcinoma, to determine the local control and 5-year salvage rate and the site and frequency of recurrences with salvage rate with a second modality.
An improved synthesis of the lipophile 18F-fluoropropane, yielding 30-45 mCi 18F-labelled radiopharmaceutical, is described. The radiochemical yield was 55%-66% determined at the end of a 1-h synthesis. Radiochemical and chemical purity of 18F-fluoropropane was 99% as determined by gas chromatography. Low-temperature autoradiography was used to investigate the lipophile 18F-n-fluoropropane as a myelin tracer for use with positron emission tomography. The white to grey matter ratio based on autoradiograms 12 min after administration of the radiotracer was 2:1, the highest reported to date.
A new method for continuous monitoring of the concentration of 131I-labelled iodoantipyrine during an autoradiographic local cerebral blood flow (LCBF) experiment is described. During infusion of iodoantipyrine, radioactivity in an external femoral arteriovenous loop is monitored by a scintillation detector. Data is collected with a variable time base, and the arterial activity curve displayed visually in its entirety. The main advantage of this method is that there is no blood loss. It will therefore be of particular importance in dual-label autoradiography. This method can also be used for other gamma-emitting blood flow tracers, e.g. 123I-iodoantipyrine.
This article reports the evaluation of [18F]-4- fluoroantipyrine (FAP) as a quantitative blood flow tracer by comparing blood flow measured with [18F]FAP to that determined simultaneously with [14C]-4-iodoantipyrine (IAP), a standard blood flow tracer, by means of double-tracer autoradiography. The single-pass extraction value (m), which indicates diffusibility of a tracer, was determined according to the procedure described by Crone . The diffusibility of FAP was essentially the same as that of IAP. The brain-blood partition coefficient for FAP was found to be similar to that for IAP, 0.89 +/- 0.01. Values of local cerebral blood flow obtained with FAP agree with those determined with IAP. From these results, we concluded that FAP is indeed as good a blood flow tracer as IAP. Since 18F is a positron-emitting radionuclide, it might be a useful tracer for blood flow measurement by positron emission tomography.
We have reported a quantitative double tracer autoradiographic technique for the simultaneous measurement of local cerebral blood flow (LCBF) and local cerebral glucose utilization (LCGU) using 14C-IAP and 18F-FDG respectively. Six awake normal rats and 3 left middle cerebral artery (MCA) occluded rats were used for this experiments. A 50-hold greater radioactivity of 18F was administered and the first exposure was done for 2 hours to obtain a 18F image. Three days later (39 half-lives of 18F), a second exposure was done for 5 to 6 days to obtain the 14C image. Tissue concentration of 14C was measured relative to the commercially available 14C-methyl methacrylate standards. 18F standards were prepared in each experiment. Cross contamination of 14C in the first exposure was less than 2% in the normal state and less than 4% even in the uncoupling condition. The values obtained by this methods for LCBF and LCGU agreed closely with those obtained by a single tracer technique previously reported in the literature. The technique outlined in this paper also provided local glucose utilization flow ratio (LGFR) for the first time. LGFR was obtained by dividing the LCGU image by LCBF image and was expressed as percent mumol/ml. The mean LGFR of control rats was 76 +/- 8% mumol/ml. In a MCA occlusion group, LGFR of ischemic cortex increased until 2 to 3 times higher than that of contralateral non-ischemic cortex. Oxygen glucose index image which was obtained from the LCGU and A-V differences of O2 showed that approximately half of the glucose was metabolized anerobically.(ABSTRACT TRUNCATED AT 250 WORDS)
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The nitrosoureas are widely used in the chemotherapy of brain tumors, two of the most common being 1,3-bis(2-chloroethyl)nitrosourea and 1-(2-chloroethyl)-3-cyclohexyl-1-nitrosourea. However, we do not understand how these compounds work, nor do we know which part of the molecule has antitumor activity. In six patients with brain tumor, we measured the kinetic behavior of positron-labeled 1,3-bis(2-chloroethyl)nitrosourea in both the tumor and the normal brain with the aid of positron emission tomography; we also analyzed the distribution of radioactivity in plasma. We found the clearance of total radioactivity from the tumor to be significantly slower than from the contralateral brain and plasma, indicating a different rate of 1,3-bis(2-chloroethyl)nitrosourea decomposition in the tumor than in normal brain.
In a retrospective study, 107 patients with squamous cell carcinoma of the nasopharynx were reviewed. One hundred six patients were treated primarily by radiation therapy and only one by surgery. The overall 5 year survival rate free of disease was 29 percent. Possible prognostic factors of age, sex, cancer stage, histopathology, and treatment were studied. The younger patients did significantly better. Patient's sex and clinical stage were not significant factors in this study. The patients with lymphoepitheliomas, anaplastic carcinomas, and those with poorly differentiated cell types did significantly better than those with more differentiated lesions. Fifty-five patients received irradiation therapy of 6,000 rads by external ports alone, and 51 patients received radiation therapy of 6,000 rads by external ports supplemented by 1,500 rads using an intracavitary radium applicator. The higher survival rate with the use of the supplementary dosage was only suggestively significant.
Forty-five patients had a "total" glossectomy for initial advanced tongue carcinoma or for recurrent carcinoma. Forty percent of the patients (18) had a total laryngectomy at the time of glossectomy. Forty-nine percent of the patients (22) had either a lateral or anterior mandibulectomy at the time of glossectomy. Seventy-one percent of the patients (15 of 21) who had an intact larynx and 12.5 percent who had laryngectomy (3 of 24) had some degree of useful speech. Thirty-one percent of the patients (14 of 45) had no problems in deglutition whereas 53 percent of the patients (24) needed a nasogastric tube, 4 patients inserted the feeding tube themselves, 2 had a cervical esophagostomy, and 1 had a special prosthesis for feeding purposes. Thirty-seven percent of the patients (10 of 27) had considerable aspiration problems. Twenty-two percent (6 patients) needed a laryngectomy, and 7.5 percent (2 patients) needed a cervical esophagostomy to prevent further problems. Seven and one-half percent of the patients (2) succumbed to serious pulmonary infection. In this study, total glossectomy had a salvage rate of 65 percent at 6 months postoperatively, 27.5 percent at 1 year, 25 percent at 2 years, 25 percent at 3 years, 20 percent at 5 years, and 10 percent at 10 years.
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A segmental anterior mandibulectomy causes severe functional disability and cosmetic problems. Many methods of reconstruction have been used but none of these procedures provides the ideal solution. There has been increasing interest in the possibility of preserving a portion of the anterior mandibular arch and still carrying out an adequate surgical excision to control the primary tumor. Over a 15-year period, 251 patients with cancer of the floor of mouth were seen and treated at Roswell Park Memorial Institute. Of this group, 34 patients underwent a marginal mandibular resection as part of their curative surgical treatment. The complication rate was acceptable and the 5-year determinate survival rate was 84%. The local control rate was excellent with only one patient developing an intraoral recurrence which was successfully treated with radiation. It is felt that these data support the theory that conservative mandibular surgery can be carried out in selected cases without jeopardizing the concept of a good cancer operation.
During a 20-year period, 77 patients who underwent ligation of the common or internal carotid artery were analyzed for the site, side of hemorrhage and/or ligation, with incidence of rebleed, previous treatment (surgery and/or radiation therapy), the type of incision utilized for resection, the incidence of preoperative and intraoperative hypotension and hemiplegia. The immediate mortality and subsequent follow-up of the patients were also noted.
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