Biomedical subjects
Publications and source records attributed to S Nishimura.
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The effect of multi-porous beads prepared from 80% deacetylated chitin on the activation of mouse peritoneal macrophages was examined. Deacetylated chitin bead (DAC-bead) preparations were shown to activate macrophages for tumoricidal activity depending on the increasing concentration of acetic acid used for the pretreatment of beads. The large DAC-bead was more susceptible to treatment with acetic acid than small DAC-bead, and showed more potent capacity for the activation of macrophages under the same pretreatment conditions with acetic acid. Deacetylated bead preparations, on the other hand, showed less activities. In addition, DAC-bead pretreated with acetic acid stimulated macrophages to produce interleukin 1. The possibilities of multi-porous beads as cancer chemotherapeutic-carrier were examined by the method of column chromatography and of in vitro antitumor experiment. Forty-four percent of adriamycin adsorbed on the surface of and in bead was released within the first 60 min. of elution, and then adriamycin was released more slowly in proportion to the elution time. Antitumor activity of adriamycin-adsorbed bead was less effective than that of free adriamycin if they were compared on the basis of total content of adriamycin.
Rotavirus RNA was detected in the blood and cerebrospinal fluid from eight Japanese children with convulsions and gastroenteritis in the acute stage by means of the reverse transcription polymerase chain reaction. This may suggest that rotavirus invades the central nervous system through blood vessels.
The three-dimensional ultrastructural changes of the glomerular extracellular matrices in diabetic glomerulosclerosis were studied in acellular rat and human diabetic glomeruli by scanning electron microscopy. The mesangial matrix appeared as fenestrated septa with oval stomata between the glomerular capillaries in normal control specimens. In diabetic glomerulosclerosis, both in humans and rats, expansion of mesangial matrix and narrowing of the mesangial fenestrae were observed. A thin layer of the mesangial matrix extended into the peripheral glomerular basement membrane (GBM) subendothelially. Thickening of the GBM in diabetic nephropathy might be due to expansion of the mesangial matrix into the peripheral GBM.
The carcinogenicity of thiamphenicol (TAP), an antibiotic drug, was examined in Fischer 344 rats of both sexes. TAP was given ad lib. in drinking water at levels of 0 (control), 125 or 250 ppm to groups of 50 male and 50 female rats for 2 yr. The treatment did not affect mortality and no toxic lesions were specifically induced. Furthermore, the incidence of tumours in the treated groups did not show any significant dose-related increase as compared with the control group. The results thus indicate that TAP is neither toxic nor carcinogenic, for any organs or tissues of F344 rats when given continuously at levels of 125 or 250 ppm in drinking water for 2 yr.
It has been shown previously that deoxyguanosine residues in DNA are hydroxylated at the C-8 position both in vitro and in vivo to produce 8-hydroxydeoxyguanosine (8-OH-dG) by various agents that produce oxygen radicals such as reducing reagents-O2, metal ions-O2, polyphenol-H2O2-Fe3+, asbestos-H2O2 or ionizing radiation. These agents are mostly either mutagenic or carcinogenic; therefore, the formation of 8-OH-dG can also be considered a likely cause of mutation or carcinogenesis by oxygen radicals. It is of interest to know whether the 8-OH-dG residue in DNA is misread during DNA replication. To answer this question, we have examined the effect of the 8-OH-dG residue in DNA on the fidelity of DNA replication using a DNA synthesis system in vitro with Escherichia coli DNA polymerase I (Klenow fragment). The synthetic oligodeoxynucleotides, with or without an 8-OH-dG residue in a specified position, were chemically synthesized and used as templates for DNA synthesis under the conditions of the dideoxy chain termination sequencing method. Surprisingly, in addition to misreading of the 8-OH-dG residue itself, pyrimidines next to the 8-OH-dG residue (G has not yet been tested) were also misread.
Magnetic resonance studies of 12 fourth ventricle tumors were reviewed. The relationship between the tumor and surrounding structures, such as the corpus medullare, the superior medullary velum, and the quadrigeminal plate, was assessed on midsagittal inversion recovery images. Two of the 12 tumors displaced the superior medullary velum superiorly. Seven of the 12 tumors displaced the corpus medullare posteriorly. The superior medullary velum was not recognized in 10 cases and the corpus medullare in 5. Ten of 12 quadrigeminal plates were displaced superoposteriorly due to focal enlargement of the cerebral aqueduct secondary to large intraventricular tumors. In the remaining two cases the tumor was not large enough to enlarge the cerebral aqueduct. The larger the tumor was, the more frequent was the displacement of the quadrigeminal plate. On T2-weighted images, CSF flow-void sign was seen around the tumor in 5 of 12 cases. We consider superoposterior displacement of the quadrigeminal plate to be a relatively constant and reliable sign accompanying fourth ventricle tumors.
The magnetic resonance appearance of dural arteriovenous fistulas (AVFs) at the cavernous sinus (CS) was studied in six angiographically verified cases. Magnetic resonance clearly demonstrated shunted blood as an area of signal void both in the CS and in the superior ophthalmic vein. The relationship between shunted blood, internal carotid artery, and extraocular nerves, as well as proptosis, enlargement of the extraocular muscles, and bulging of the lateral wall of the CS were also depicted in the images. Normal venous flow in the involved CS was shown as a low signal area that enhanced after gadolinium administration. Magnetic resonance is useful for screening and follow-up examinations of dural AVFs at the CS. It is essentially a noninvasive procedure that may be repeated and obviates the need for follow-up angiography. However, it should be noted that a signal void in the CS sometimes represents normal venous flow. A definite diagnosis should rely on angiography, which is essential for therapeutic planning.
When breast-conserving therapy was introduced at the Cancer Institute Hospital (CIH) in Tokyo in 1986, we instituted our own strategy as follows: 1) every effort is to be made for complete tumor resection while avoiding deformity of the breast, and 2) radiotherapy (RT) is applied only to the patients with positive surgical margins. This is, in turn, to clarify the group of patients in whom postoperative RT can be safely spared. Among 9670 patients operated on for primary breast cancer during the 16.5 year period from 1986 to 2002 at CIH, there were 2449 patients who underwent breast-conserving surgery (BCS). During the 6.5 years mean follow-up period, ipsilateral intrabreast tumor recurrence (IBTR) developed in 99 of the 2449 patients, with an overall rate of 4.0% and an annual rate of 0.62%. These 2449 patients were categorized into four subgroups according to either negative or positive margins and with or without radiotherapy. The IBTR rates and the number of patients in each subgroup were 5.5% in 1351 margin(-)RT(-) patients, 1.0% in 307 margin(-)RT(+) patients, 2.4% in 680 margin(+)RT(+) patients, and 4.5% in 111 margin(+)RT(-) patients. These results either with or without RT seem to be quite comparable to or even better than the results of BCS with RT reported from Western countries, where less emphasis seems to be placed on completeness of the local tumor resection with BCS, while RT is administered to basically all patients following BCS. IBTR was categorized into true recurrence (TR) and second primary lesion (SP) according to the margin status at the time of BCS, the former being lesions developed in patients with positive margins and the latter being those in patients with negative margins. It was demonstrated that in patients with positive margins, TR was much more common than SP, whereas in patients with negative margins, these incidences were just the opposite (i.e., TR was 60% less common than SP) and postoperative RT was effective in preventing both TR and SP, the effect on the latter being much more striking. With RT, the incidence of developing TR in patients who had positive margins was reduced to almost equal to that in margin(-) patients treated with no RT. Our method of IBTR categorization is based on biological consideration and detailed histopathologic examination, and appears to be the only biologically reasonable means so far that has been proposed for distinction between these two biologically different entities. TR and SP can be further reduced to exceptionally low levels in patients who received RT despite negative margins, though it would not seem reasonable to administer RT to all of these patients because the actual number of patients who would benefit is comparatively small. From these observations, it seems that our imaging, pathologic examination, and surgical approaches for patients who are candidates for BCS have been highly valid, and our criteria for sparing postoperative RT as well as categorization of IBTR into TR and SP are quite appropriate. Although our results with BCS seem to deserve wide recognition, they are not from randomized clinical trials, so the findings must be confirmed by a study in order to investigate whether the results at CIH can be applied generally at other institutions.
BACKGROUND: This study is comprised of 3493 consecutive patients who underwent open heart surgery at our institution. Data on all patients were collected prospectively. METHODS: In 45 patients (Group P) (1.3%), a permanent pacemaker (PP) was inserted postoperatively. For the purpose of the study, these patients were compared to 3448 patients (Group NP) who did not require insertion of a PP after surgery. Mean follow-up was 33 months (range 1.5 to 66). RESULTS: We found Group P patients were older (64.8 +/- 11.0 vs 61.0 +/- 11.0 years, p < 0.05), had a higher proportion of elderly (> 70 years) 36% vs 19%, p = 0.01), and of female patients (48.8% vs 22.7%, p < 0.001) compared to Group NP. Group P also had a higher incidence of preoperative rhythm abnormalities (26.6% vs 5.7%, p < 0.0001), redo surgery (13.3% vs 4.6%, p = 0.02), aortic valve surgery (48.8% vs 10.8%, p < 0.001), and tricuspid valve surgery (repair 3, replacement 1) (8.8% vs 0.5%, p < 0.001), in addition to a higher proportion of patients in whom cold (vs warm) blood cardioplegia was used (68.8% vs 52.3%, p = 0.03). Indication for postoperative PP was sick sinus syndrome (SSS) in nine patients; atrial fibrillation in eight patients; atrioventricular block (AVB) in 27 patients; and combined AVB/SSS in 1 patient. There were no operative deaths in Group P. Necessity for PP after heart surgery had a significant impact on resource utilization resulting in prolonged ventilation (3.1 +/- 7.5 vs 1.4 +/- 3.3 days, p < 0.01), intensive care unit (5.1 +/- 10.2 vs 2.5 +/- 4.0 days, p < 0.01), and postoperative hospital stay (18.0 +/- 13.4 vs 8.1 +/- 9.4 days, p < 0.01). CONCLUSIONS: By multivariate logistic regression (odds ratio and p value in parentheses), aortic valve surgery (8.23, p = 0.001), the absence of preoperative sinus rhythm (5.60, p = 0.001), postoperative myocardial infarction (3.46, p = 0.024), and female gender (2.52, p = 0.003), were found to be independent predictors for PP requirement post surgery.
Two patients presenting with asthma as the first clinical symptom of a mild form of Addison crisis were found to have complex glycerol kinase deficiency (CGKD). They had been treated with bronchodilators prior to the exact diagnosis. Asthma may appear in a mild form of Addison crisis in a patient with CGKD. Pediatricians should be aware of this unusual presentation of CGKD.
A 28-year-old woman developed central pontine myelinolysis (CPM) following severe hyponatremia. Radiological examinations demonstrated a characteristic pontine lesion of CPM. Her neurological symptoms (drowsiness, emotional lability, dysarthria, dysphagia, and quadriparesis) were improved dramatically by treatment with thyrotropin-releasing hormone (TRH) and rehabilitation. However, results of repeat computed tomographic (CT) scans of the brain remained unchanged. This case therefore suggests that TRH may be beneficial for the treatment of CPM, and that CT findings appear to be a limited prognostic indicator for CPM.
We investigated results for thoracic T3-T4 esophageal squamous cell carcinoma in two strategies. The protocol group (46 patients) consisted of neoadjuvant chemoradiotherapy (44 Gy, CDDP, 5-FU), followed by either definitive radiotherapy (total 70 Gy) for responders or surgery for non-responders. The surgery group (26 patients) underwent esophagectomy with regional lymph node dissection. Nineteen of them received postoperative radiotherapy. Surgical candidates in both groups received intraoperative radiotherapy for abdominal lymphatics since 1991. In the protocol group, 23 patients underwent radical surgery after neoadjuvant chemoradiotherapy and the remaining 23 underwent definitive radiotherapy. The rates of recurrence were 64% in the protocol group, and 62% in the surgery group. Overall 3- and 5-year survival rates were 48% and 31% in the protocol group compared to those of 30% and 30% in the surgery group. The rate of the was 39% in the protocol group. There was no mortality in either group. Our protocol had at least comparable prognostic values with historical conventional surgery, and was excellent in having feasibility for organ preservation.
Cells from benign and borderline malignant mucinous cystadenomas surgically resected from three postmenopausal women with elevated serum estradiol levels were found to have different abilities to synthesize estrogen from [14C]-cholesterol. Addition of gonadotropins to cultured cells with low levels of estrogen synthesis did not result in any significant increase in estrogen synthesis. Immunohistochemical studies of these mucinous cystadenomas showed that LDL receptors were distributed in the benign cystadenoma cells and in the stromal cells of borderline tumors, but not in the cystadenoma cells of borderline tumors. Sterol regulatory element binding protein was immunohistochemically shown to be distributed in the mucinous cystadenoma cells of borderline tumors, but not in the benign cystadenoma cells.
A 65-year old woman operated on for verrucous carcinoma of the uterine cervix 13 years previously was found to have multiple small recurrent tumors in the retroperitoneal space. Tumor cell expression of vascular endothelial growth factor (VEGF) and platelet-derived endothelial cell growth factor (PD-ECGF) was investigated at the second operation. Expression of VEGF was strongly positive in the tumor cells and expression of PD-ECGF was strongly positive in both the tumor cells and the interstitial cells.