Biomedical subjects
Publications and source records attributed to H Fukuda.
We have examined the extradural space using a flexible extraduroscope in 74 patients undergoing extradural anaesthesia at the L2-3 interspace. Extraduroscopy showed that the extradural space becomes widely patent and the fatty tissue in the extradural space diminishes with increasing age. We postulate that these age-related structural changes may affect the spread of local anaesthetic in the extradural space.
To clarify the effects of the pregnant uterus on the extradural venous plexus in the supine and lateral positions, we studied magnetic resonance (MR) images of the lumbar spine in three parturients. T2-weighted axial MR images were obtained with the parturient in the supine and lateral positions. On each slice level in the same subject, the MR images were compared with the control MR images obtained before pregnancy. When the parturient lay supine, the pregnant uterus compressed the inferior vena cava and almost totally obstructed it; the extradural venous plexus was engorged. On turning the parturient into the lateral position, the inferior vena cava was free from compression, and the engorged extradural venous plexus was found to shrink to the level of the non-pregnant state.
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To clarify the anatomy of the extradural space of the thoracic spine, we have compared magnetic resonance (MR) images of the thoracic spine with those of the lumbar spine. In 20 healthy volunteers, T2-weighted axial MR images were obtained at the levels of the C7-T1, T7-8, T11-12 and L2-3 vertebrae. The posterior extradural space seen in the slice through the intervertebral disc varied in shape and size depending on the vertebral level, and the shape of the space converted from triangular to crescent-shaped on moving from the lumbar to the thoracic spine. In particular, the posterior extradural space was almost absent at the C7-T1 level, indicating that the posterior extradural fat was rudimentary or non-existent at the thoracocervical level. At this level, the dura mater seemed to be in direct contact with the ligamentum flavum. Segmentation of the posterior extradural space was commonly observed at the L2-3 and T11-12 levels; however, incomplete segmentation of the posterior extradural space was often present at the T7-8 level.
The paper gives guidelines to authors on the use of statistics, including statistical considerations when designing studies. Information on this article plus a list of other recommended books is available on the World Wide Web (http:/(/)wwwinfo.ncc.go.jp/jjco/) in Japanese as well as English.
To investigate the effects of different dietary fatty acids and proteins on glucose tolerance and insulin receptor gene expression, Wistar fatty rats (genetically obese, noninsulin-dependent diabetes mellitus) and their lean littermates (8 wk old) were fed a casein or soybean protein diet containing 9% partially saturated beef tallow (plus 1% corn oil), 10% corn oil or 10% fish oil for 3 wk. In glucose tolerance tests, plasma insulin concentrations were significantly higher in obese rats fed corn oil or fish oil than in those fed partially saturated beef tallow, particularly in the soybean protein groups. However, plasma glucose concentrations were not significantly affected by dietary protein or fat. The insulin receptor mRNA concentrations in livers and adipose tissues were higher in rats fed soybean protein/partially saturated beef tallow than in those fed any other protein/fat combination. Dietary soybean protein may help to reduce the insulin resistance, but only when a diet low in polyunsaturated fatty acids is consumed. On the other hand, the insulin receptor mRNA concentrations in adipose tissue were generally lower in the obese rats of all dietary groups than in the lean rats, suggesting that insulin resistance may be due to a defect of insulin receptor gene expression.
To elucidate the involvement of brassinosteroids in the progression of tracheary element differentiation in cultured Zinnia cells, we analyzed the effects of uniconazole, an inhibitor of brassinosteroid synthesis, and brassinolide, a biologically active brassinosteroid, on the accumulation of mRNAs for various genes that were expressed in different stages of differentiation. Uniconazole specifically suppressed the accumulation of transcripts for genes that were induced in the final stage of differentiation in association with secondary wall formation and cell death. This suppression was recovered with the addition of brassinolide. These results strongly suggest that endogenous brassinosteroids induce entry into the final stage of differentiation.
Changes in the enzymatic activity of cinnamyl alcohol dehydrogenase (CAD) and in the expression of a gene for CAD during tracheary element (TE) differentiation were investigated in cultures of single cells isolated from the mesophyll of zinnia (Zinnia elegans). In cultures in which TE differentiation was induced (TE-inductive cultures), CAD activity increased from h 36 after the start of culture (12 h before the start of thickening of the secondary cell wall) and peaked at h 72, when lignin was actively being deposited. In control cultures in which TE differentiation was not induced, CAD activity remained at a very low level for 5 d. Some isoforms of CAD were detected only in the TE-inductive cultures by native gel electrophoresis and subsequent staining for CAD activity. A cDNA clone for CAD, ZCAD1, was isolated from Z. elegans using a cDNA clone for CAD from Aralia cordata as the probe. RNA gel-blot analysis revealed that in the TE-inductive cultures the level of ZCAD1 mRNA increased from h 36 and peaked at h 48 to 60. No such increases were observed in control cultures. These results indicated that both the gene expression and the activity of CAD are strictly regulated, in association with lignification, during TE differentiation in Z. elegans.
Telomerase activity was examined by telomeric repeat amplification protocol assay in thyroid disease states, including adenomas and carcinomas, and correlated with clinicopathological features. Of a total of 26 papillary carcinomas, 16 cases (61.5%) were positive, with the poorly differentiated subtype being predominant (P < 0.05). A significantly more shortened terminal restriction fragment length (P < 0.05), higher incidence of extrathyroidal extension (P < 0.001), and more elevated Ki-67 labeling indices (P < 0.002) were also found in telomerase-positive than in telomerase-negative papillary carcinomas. Of four follicular carcinomas, 3 cases (75.0%) were positive. Positive telomerase activity in follicular adenomas (9/23 cases, 39.1%) and lymphocytic thyroiditis (12/22 cases, 54.5%) appeared to be mainly caused by infiltrating lymphocytes. However, three cases of atypical adenoma with relatively increased Ki-67 labeling indices were positive, suggesting a possibility of malignant potential. The good correlations with extrathyroidal invasiveness, Ki-67 labeling indices and poor differentiation of papillary carcinomas, established by multivariate analysis, suggest that this parameter might have potential application in the estimation of tumor progression and prognosis, and in clinical management.
OBJECTIVE: To estimate the prevalence and risk factors of urinary and fecal incontinence among a community-residing older population in Japan. DESIGN: Population-based cross-sectional study. SUBJECTS: A randomly selected sample of 1473 people aged 65 years and older living in the City of Settsu, Osaka, in 1992. MEASURES: Data collected via in-home visits were used to estimate the prevalence of urinary and fecal incontinence and to provide information regarding potential risk factors of urinary and fecal incontinence. RESULTS: Data were obtained from 1405 older adults, a response rate of 95.4%. The prevalence of any degree of urinary incontinence was 98/1000 in both sexes, and 87/ 1000 men and 66/1000 women admitted to some degree of fecal incontinence. Daily, 34/1000 and 20/1000 of the population were incontinent of urine and feces, respectively. There was an increasing prevalence of urinary and fecal incontinence with age in both sexes, but the expected greater prevalence in women was not found. By univariate analyses, age older than 75 years, poor general health as measured by Activities of Daily Living, stroke, dementia, no participation in social activities, and lack of life worth living (Ikigai) were associated significantly with both urinary and fecal incontinence. In the multivariate analyses using logistic regression, age older than 75 years, poor general health, and stroke were independent risk factors for any type of incontinence. Diabetes was an independent risk factor for isolated fecal incontinence, and dementia and no participation in social activities were independent risk factors for double incontinence. CONCLUSIONS: Incontinence of urine and feces is a prevalent condition among very old people living in the community in Japan and is associated highly with health and psychosocial conditions.
Salivary gland scintigraphy was performed on 52 patients who were suspected of having Sjögren's syndrome (SS), and the results were compared with clinicopathologic features of the salivary and lacrimal glands. The time-activity curves which were obtained from computer-assisted analysis of 99mTc-pertechnetate (99mTc) scintigraphy were classified into four types (normal, median, flat and sloped types). The stimulated parotid flow rate decreased and the incidence of SS-related sialographic and histopathologic findings increased significantly as the scintigraphic abnormality advanced. In addition, the lacrimal gland function decreased and the proportion of patients diagnosed as having keratoconjunctivitis sicca (KCS) increased significantly as the scintigraphic abnormality advanced. These results indicate that the results of scintigraphy are related not only to the clinicopathologic features of the salivary glands but also to the lacrimal gland function in SS.
We report two cases of failure of fluoroquinolone treatment of urinary tract infections with Klebsiella pneumoniae strains harboring quinolone resistance-associated alterations in GyrA and ParC and in vivo selection of posttreatment isolates with enhanced fluoroquinolone resistance. Active efflux leading to decreased accumulation of a drug enhanced fluoroquinolone resistance in one posttreatment isolate, and an additional mutation in parC resulting in an additional amino acid change in ParC was associated with increased resistance in the other.
BACKGROUND: We report here a rare case of repeated syncopal episodes associated with smoking and findings of 99mTc-hexamethylpropyleneamine oxime (HMPAO) brain single-photon emission CT (SPECT) imaging. CASE DESCRIPTION: A 77-year-old man had four syncopal episodes during a half-month period. All four occurred when he stood up and walked immediately after smoking a cigarette, and syncope did not occur after cessation of smoking. Although upright testing revealed orthostatic hypotension, the patient did not complain of fainting on standing alone. Compared with brain SPECT in the supine position, perfusion was decreased in the posterior circulation structures after the subject smoked a cigarette or chewed nicotine gum. CONCLUSIONS: The combination of cerebral vasoconstriction due to smoking and orthostatic hypotension probably decreased cerebral blood flow in this patient, resulting in syncope.
PURPOSE: A dose-escalation study of irinotecan hydrochloride (CPT-11) combined with fixed-dose cisplatin was conducted to determine the maximum-tolerated dose (MTD), dose-limiting toxicities, and objective response rate in patients with advanced gastric cancer. PATIENTS AND METHODS: Twenty-four patients with or without prior chemotherapy were enrolled. All patients were assessable for toxicities and response. On day 1, CPT-11 was administered as a 90-minute intravenous (I.V.) infusion, which was followed 2 hours later by a 120-minute I.V. infusion of cisplatin 80 mg/m2. CPT-11 alone at the same dose was administered again on day 15. The treatment was repeated every 4 weeks until disease progression was observed. The initial dose of CPT-11 was 60 mg/m2, and was escalated in increments of 10 mg/m2 until severe or life-threatening toxicity was observed. RESULTS: The MTD of this combination was CPT-11 80 mg/m2. At this dose level, 16.7% of patients (two of 12) had leukopenia of less than 1,000/microL, 66.7% (eight of 12) had neutropenia of less than 500/microL, and 16.7% (two of 12) had severe diarrhea of grade 4 during the first course. The dose-limiting toxicity was neutropenia. Ten patients achieved a partial response (PR), and the overall response rate was 41.7% among 24 patients (95% confidence interval, 21.9% to 61.4%). CONCLUSION: The recommended dose and schedule is CPT-11 70 mg/m2 on days 1 and 15 and cisplatin 80 mg/m2 on day 1 every 4 weeks. This combination of CPT-11 and cisplatin, considered to be active against advanced gastric cancer with acceptable toxicity, should be further assessed in a phase II study.
Experiments were performed to examine the roles of gamma-aminobutyric acid(B) (GABA(B)) and gamma-hydroxybutyric acid (GHB) receptors in long-term potentiation (LTP) of the hippocampal CA1 region in vivo and in the genesis of the spike and wave discharges (SWDs) associated with absence seizures. When tetanic stimulation was delivered to the CA3 region, stable LTP was observed in the CA1 region in saline-treated mice. In mice treated with 5 mg/kg baclofen, the population spike amplitude was significantly potentiated by tetanic stimulation and the degree of potentiation was the same as that induced in saline controls. However, this potentiation decayed to the baseline level about 90 min after stimulation. The decay was reversed by pretreatment with 200 mg/kg P-[3-aminopropyl]-P-diethoxymethylphosphinic acid (CGP 35348), a selective GABA(B) receptor antagonist. In mice treated with 50 mg/kg gamma-butyrolactone (GBL), a prodrug of GHB, stable LTP was observed 90 min after tetanic stimulation and was greater than that in saline controls. GBL-induced potentiation of LTP was antagonized by 50 mg/kg NCS 382, a putative GHB receptor antagonist. Administration of baclofen (20 mg/kg) or GBL (70 mg/kg) induced absence-like seizures associated with 3-6 Hz SWDs, and CGP 35348 suppressed both baclofen- and GBL-induced SWDs. NCS 382 also attenuated SWDs induced by GBL and baclofen. These results suggest that baclofen and GHB have different effects on LTP in the CA1 region of the hippocampus in vivo, although they have a common mode of action on the thalamocortical functions related to the pathogenesis of absence seizures.
In a previous study we indicated the involvement of the N-methyl-D-aspartate (NMDA) receptor in the development of morphine dependence as assessed by naloxone-induced rise in norepinephrine release in chronically morphine-treated rats. In the present experiments, we studied (1) the possible role of protein kinases in the increased norepinephrine release occurring after naloxone injection and (2) the effects of NMDA receptor antagonists on chronic morphine exposure-induced changes in protein kinase activity. The naloxone-induced rise in norepinephrine release was attenuated by concomitant administration of a protein kinase inhibitor, 1-(5-isoquinolinesulfonyl)-2-methylpiperazine hydrochloride (H-7) or an NMDA receptor antagonist, (+)-5-methyl-10, 11-dihydro-5H-dibenzo[a,d]-cyclohepten-5, 10-imine hydrogen maleate (dizocilpine, MK-801) with morphine. Both cAMP-dependent protein kinase (PKA) and protein kinase C (PKC), which mediate neurotransmitter release, were clearly activated in the cytosol of the pons/medulla, but not in that of the hippocampus, in chronically morphine-treated rats. This activation of PKA and PKC by chronic morphine treatment was inhibited by infusion of dizocilpine or D(-)-2-amino-5-phosphonopentanoic acid (AP-5), an ionotropic glutamate receptor antagonist, together with morphine. These results suggest that NMDA receptor antagonists inhibit the increase in protein kinase activity produced by chronic morphine treatment, thus suppressing the naloxone-induced rise in norepinephrine release.
To evaluate the effect of prostagrandin E1 (PGE1)-induced hypotension on cerebral blood flow (CBF) and carbon dioxide (CO2) reactivity of CBF, regional cerebral hemoglobin oxygen saturation (rSo2) was measured in non-neurosurgical patients (n = 10) under sevoflurane-anesthesia using near infrared spectroscopy. PGE1 was infused intravenously to maintain arterial pressure at a level of about 75% of the MAP (hypotensive group) under sevoflurane-anesthesia alone (normotensive group). Ventilation was controlled to adjust PaCO2 to hypocapnia (25-30 mmHg), normocapnia (35-40 mmHg) and hypercapnia (45-50 mmHg) in both normotensive and hypotensive groups. rSo2 during hypotension did not change by hypocapnia and normocapnia, but significantly increased by hypercapnia, compared with rSo2 during normotension. Significant correlations between rSo2 and PaCO2 during both normotensive and hypotensive groups were observed. Slope of the regression line of rSo2 and PaCO2 did not differ between the normotensive and hypotensive groups. When arterial oxygen content and cerebral metabolic rate of oxygen are constant, changes in rSo2 correlate with those of CBF. Therefore, CBF and CO2 reactivity of CBF that indicates autoregulation in response to changes in CO2 during hypotension were maintained as those during normotension. The results show that PGE2-induced hypotension maintains CBF and CO2 reactivity well in non-neurosurgical patients under sevoflurane anesthesia.
In previous work we found a 30% increase in the effectiveness of the photodynamic treatment of cancer when combined with the administration of cyclophosphamide (CPM). Here we have tried to elucidate the mechanism responsible for such potentiation. Male Balb/C mice bearing a transplantable adenocarcinoma were given 2 or 3 doses of 150 mg of CPM/kg weight intraperitoneally. At 16 and 40 hrs. after the last injection the animals were sacrificed. Tumor and liver were excised and 5-aminolevulinic acid dehydratase and porphobilinogen deaminase activities were determined. Intracellular levels of glutathione and cytochrome P450 were also measured. A 15 to 30% decrease in liver 5-aminolevulinic acid dehydratase activity was observed 40 hrs. after the last injection. The tumor enzyme was 30 to 40% inhibited. The activity of liver porphobilinogen deaminase in CPM treated mice decreased to a minimum (15% below the control) at 16 hrs. after administration of the drug and in tumors a decrease of 20% was shown 40 hrs. post CPM injection. The greater the number of CPM doses administered the higher the decrease in the enzymatic activities. CPM treatment did not change total tumor glutathione levels but the reduced/oxidized glutathione ratio was significantly modified in the tumoral tissue. Cytochrome P450 levels were not increased. These data indicate that CPM-induced potentiation of the photodynamic damage of tumoral tissue is mediated by a mechanism other than that of increased porphyrin synthesis.