Biomedical subjects
Publications and source records attributed to Y Fukushi.
The exudates of Hypochoeris radicata leaves stressed with cupric chloride afforded two eudesmane- and guaiane-type sesquiterpenes, and two alkenals, (2E,4E)-6-hydroxyhexadienal and (2E,4E)-hexadienedial (mucondialdehyde). Their structures were determined by spectroscopic and synthetic methods.
The store-mediated Ca2+ entry was detected in single and cluster of rat submandibular acinar cells by measuring the Ca2+ activated ionic membrane currents. In the cells where intracellular Ca2+ was partly depleted by stimulation with submaximal concentration of acetylcholine (ACh) under a Ca2(+)-free extracellular condition, an employment of external Ca2+ in the absence of ACh caused a sustained increase of the K+ current without affecting the Cl- current. A renewed ACh challenge without external Ca2+ caused repetitive spikes of both K+ and Cl- currents due to the Ca2+ release. SK & F 96365 inhibited the generation of the sustained K+ current and refilling of the Ca2+ store following the Ca2+ readmission. It is suggested that the Ca2+ enters the cell through the store-mediated pathway new the K+ channels and is taken up by the store. Thus, only Ca2+ released from the store can activate both the K+ and Cl- currents.
When Sr2+ was introduced to the external solution after the depletion of Ca2+ from stores of submandibular acinar cells by ACh stimulation, Sr2+ entered cytoplasm of the cell, like the case of Ca2+. SK&F 96365, a Ca2+ channel blocker, or Ni2+ blocked this divalent cation entry. Sr2+ entering the cell continued to increase to a steady level, after the cessation of stimulation, when Sr2+ was present in the external solution, unlike the case of Ca2+. Ca2+ entered cells which had been stimulated with ACh in Sr(2+)-containing external solution. In the cells to which Sr2+ has been applied after the store depletion with ACh, Sr2+ cannot be released by the renewed ACh stimulation, unlike the case of Ca2+. 89Sr2+ uptake by the parotidic microsomal fraction 100 min after addition of ATP was 15.08 +/- 0.70 nmol/mg protein, whereas 45Ca2+ uptake was 144.19 +/- 16.93 nmol/mg protein. It was concluded that in the salivary acinar cells Sr2+ can be a substituent for Ca2+ in the mechanism of entry from the extracellular fluid but cannot be in the mechanism of uptake into the stores.
To elucidate the role of Kupffer cells in ischemia-reperfusion-induced hepatic injury, hepatic injury induced by ischemia-reperfusion was analyzed after modulation of Kupffer cell function. Ischemia of the liver was performed by occlusion of both the portal vein and hepatic artery, which enter into the left lateral and median lobes of the liver. Blood flow in the ischemic lobe was reduced, in contrast to an increased blood flow in the nonischemic lobe during occlusion of the veins. Although hepatocyte damage was not demonstrated by ischemia for < 60 min, hepatic injury was found after reperfusion of the liver, and activation of Kupffer cells was morphologically demonstrated by electron microscopies. Suppression of Kupffer cells, induced by previous administration of gadolinium chloride or latex particles, reduced the grade of hepatic injury induced by ischemia-reperfusion. On the other hand, stimulation of Kupffer cell phagocytosis, induced by administration of latex particles at the time of reperfusion, aggravated the ischemia-reperfusion-induced hepatotoxicity, which was then reduced by simultaneous administration of superoxide dismutase. Kupffer cells, isolated from the rats treated with the ischemia-reperfusion procedure, have been found to release increased amounts of oxygen radical intermediates. These results suggest that hepatic injury induced by ischemia-reperfusion is modulated by the function of Kupffer cells and that superoxide anion released from Kupffer cells could play an important role in ischemia-reperfusion hepatic injury.
A study was conducted to ascertain the presence of peroxidized low-density lipoprotein (LDL) in plasma and to determine the chemical structure of the peroxidized LDL so that the mechanism by which vascular complications develop may be elucidated in patients with familial hypercholesterolemia (FH). Family trees showing hypercholesterolemia and moderate grade thickness of the Achilles' tendon were confirmed in all patients. Cholesteryl ester, triglycerides (TG), free fatty acid (FFA), free cholesterol (FC), and phospholipids in normal LDL were stained on a thin-layer chromatography (TLC) plate, but from peroxidized LDL, spot X1 between TG and FFA, and spot X2 between FFA and FC were identified clearly except for the lipids recognized in normal LDL on the TLC plates. From intermediate-density lipoprotein (IDL), LDL1, and LDL2 of FH patients, spot X1 was clearly recognized. Hydroperoxidized cholesteryl linoleate (HPO-CL) was estimated and identified from Cu(2+)-treated standard CL, Cu(2+)-treated LDL and LDL obtained from FH patients by means of high-pressure liquid chromatography, mass spectrometry, nuclear magnetic resonance, positive reaction of p-methoxydiphenylpyrenyl-phosphine and various chemical reactions. The percentage of HPO-CL to total lipids in LDL was in the order of IDL < LDL1 < LDL2 in FH patients, and it was markedly higher in FH patients when compared to healthy persons. Spot X1 obtained from Cu(2+)-treated CL, from Cu(2+)-treated normal LDL and from LDL of FH patients was chemically identical, consisting of at least 4 kinds of HPO-CL isomer. LDL2-cholesterol levels were higher in FH patients than those of LDL1-cholesterol, whereas in healthy persons LDL1 cholesterol levels were higher compared to those of LDL2 cholesterol. The capacity of LDL2 for peroxidization by Cu2+ was greater than that of LDL1 in healthy persons. Biological functions, such as acceleration of platelet aggregation, great internalization into macrophages and injuries of the arterial endothelia, were reported for LDL with HPO-CL in our previous experiments. Thus, the existence of peroxidized LDL with HPO-CL may be one of the important risks for vascular complications in FH patients.
A 65-year-old man with an occupational history of asbestos exposure developed dysphagia and vomiting. Clinical examinations at onset revealed a dilated esophagus with smooth narrowing at the gastroesophageal junction and no apparent tumor in and around the esophagus. Achalasia was suspected. Dysphagia progressed gradually and examinations performed three months after the onset disclosed a tumor in the pleural and the peritoneal cavities. At laparotomy, the tumor extended from the pleural cavity into the peritoneal cavity. Histological examination of the biopsied specimen demonstrated malignant mesothelioma. We report the first case of malignant pleural mesothelioma presenting as achalasia.
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Testicular tumor tissues and various normal tissues were examined by immunohistochemical techniques for expression of globotriaosylceramide (Gb3) using anti-Gb3 monoclonal antibody (1A4). In formalin fixed paraffin-embedded specimens (31 cases), Gb3 was positive for every kind of elements of testicular germ cell tumors, especially it's incidence of positive staining were 100% in seminomas (16/16) and embryonal carcinomas (6/6). On the other hand, four cases of testicular malignant lymphoma were all negative for Gb3, and some normal testicle, liver, kidney, pancreas, spleen, ileum and rectum showed very weak reactivity with 1A4. In frozen materials (10 cases), similar incidence of positive staining with that of paraffin-embedded specimens were observed in drying only manner, 4% parafolm-aldehyde fixation following drying and 10 min. of acetone fixation following drying. Incidence of very strong staining in testicular germ cell tumors were as follows, 7/10 in 4% parafolmaldehyde fixation, 6/10 in drying only, 4/10 in 10 min. of acetone fixation and 7/22 in paraffinembedded specimens. Fixation with 30 min. of acetone fixation and 10 min. of 90% ethanol and treatment with 10 min. of chloroform:methanol (2:1, v/v) extremely decreased the reactivity with 1A4, suggesting that Gb3 exists mainly as glycolipid. Gb3 may thus be a useful histological marker for testicular germ cell tumor, and the tissue should be treated with the process of freezing followed by 4% parafolm-aldehyde fixation, drying only or 10 min. of acetone fixation, and formalin fixed paraffin-embedded specimens were also available enough.
Glycolipids were biochemically extracted from 14 specimens of seminoma, 2 of testicular malignant lymphoma (both of which were difficult to differentiate from seminoma with a high mitotic index) and 4 of normal testicle. The pattern of their expression was compared. Marked accumulation of globotriaosyl ceramide was observed in seminoma but it was present in a small amount in testicular malignant lymphoma. Differentiation between seminoma and malignant lymphoma is sometimes difficult by histopathological findings but it is considered to be greatly facilitated by examination of the pattern of glycolipid expression.
The mechanism of the intestinal transport of enoxacin, an orally active fluoroquinolone antibiotic, has been investigated using brush-border membrane vesicles isolated from rat small intestine. The initial rate and time-course of enoxacin uptake were considerably dependent upon the medium pH (pH 5.5 greater than pH 7.5) and upon the percent ionization of the carboxyl group (pKa 6.2, anionic charge), namely, the degree of uptake of cationic form was higher than that of the zwitterionic form. There was evidence of transport into the intravesicular space as shown by the effect of extravesicular medium osmolarity on enoxacin uptake at steady state (30 min). This transport across the brush-border membrane was stimulated by the valinomycin-induced K(+)-diffusion potential (interior negative) and an outward H(+)-diffusion potential. Furthermore, changing the pH of the medium from 5.5 to 7.5 significantly decreased the effect of valinomycin-induced K(+)-diffusion potential on the enoxacin uptake. These results suggest that the uptake behaviour of the cationic form of enoxacin plays an important role in the intestinal absorption process of enoxacin.
The expression patterns of glycolipid from prostatic hyperplasia, prostatic cancer and normal prostate tissue were observed. A further analysis of antigen recognized by mouse monoclonal antibody APG1, which was gained by immunizing glycolipids extracted from human prostate cancer, was also performed. In cancer tissue, both of the lactosyl and globoside series glycolipids were found to be generally reduced, although in the ganglioside series, GM3 and GD3 were not reduced and only the glycolipids with longer chains than GD2 were found to be reduced. These results indicated that the inhibition of sugar chain elongation, but not sialylation, was the main synthetic change occurring with carcinogenesis of the human prostate. APG1 reacted with only two bands near GM2 and GD2 of the ganglioside fraction on a thin-layer chromatography plate, but it did not react with any of the known gangliosides of the ganglioside series including GM2 and GD2. Histochemically, APG1 showed intense reaction only in frozen tissue sections of human prostate, and the reactivity decreased with the increasing grade of cancer. Therefore, this antigen was considered to be a prostate-specific and differentiated antigen reacting with nonganglioseries gangliosides.
The expression patterns of glycolipids of human renal-cell carcinoma were studied in primary tumors from 23 cases and 5 metastatic lesions from 4 cases using HPTLC (high-performance thin-layer chromatography). The expression pattern of glycolipids in primary tumors was characteristic of the histological cell type. In granular-cell carcinoma, lactosylceramide (CDH), GM3 and the longer-chain gangliosides (gangliosides migrating more slowly than GM3) increased, although in clear-cell carcinoma, CDH and other glycolipids tended to decrease. Globoside decreased in all cases but one, irrespective of cell type. In metastatic lesions of the clear-cell type, the prominent increase in longer-chain gangliosides was characteristic. Furthermore, the same expression pattern as that of metastastatic lesions was shown in 3 of 14 patients with primary clear-cell carcinoma, all of whom developed metastases soon after radical nephrectomy. These studies indicate that the increased expression of the longer-chain gangliosides in primary tumor is one of the factors associated with high metastatic potential, and also predict early post-operative development of metastasis.
To clarify whether or not normal LDL separated from normal rabbits is atherogenic, 0.75 mg of normal LDL-cholesterol in 6 ml of 0.85% saline and 6 ml of saline alone were injected every day for 5 weeks into the auricular vein of two groups of rabbits, respectively. The inoculated rabbits were fed a standard diet containing 0.5 and 1% cholesterol. Blood was drawn before injection and at 1, 2, 3 and 5 week intervals thereafter. After 5 weeks, all rabbits were sacrificed. Following exsanguination, the aorta was stained by Sudan III. The Sudan III staining was more extensive in rabbits injected with saline than in those that received LDL. In addition, plasma cholesterol, plasma phospholipid, VLDL-cholesterol and LDL-cholesterol levels were lower in LDL-injected rabbits than in those injected with saline. But HDL-cholesterol levels were not significantly different between LDL-cholesterol and saline-injected rabbits. Although the exact cause of antiatherogenic effect of normal LDL is not clear, it seems reasonable to suggest that at least some normal LDL acts as a 'good' lipoprotein, namely antiatherogenic lipoprotein, in our experimental protocol.
Renal cell carcinomas are immunohistochemically positive for oligosaccharides with the Le(x) determinant (Gal beta 1----4[Fuc alpha 1----3]GlcNAc) and its derivatives, as oncofetal antigens, and their expression is closely related to a better prognosis of the patients. This study was designed to clarify the difference in antigen localization at the ultrastructural level between renal cell carcinoma and normal tissues. In normal kidneys, Le(x) detected by monoclonal antibody (MAb) FH 2 and sialylated extended Le(x) (sialyl Le(x)-i) by MAb FH 6 were identified along the plasma membrane of microvilli of proximal tubule epithelial cells, with occasional immunoreactivity along the basolateral plasma membranes. Intracellular localization was very sparse. Renal cell carcinoma showed localization of Le(x) and sialyl Le(x)-i antigens along the cell membrane and in the cytosol as aggregates or filaments. Immunoreactive materials were also observed in the lumen formed among carcinoma cells. The cytosolic immunoreactivity, not observed in the normal kidney, was regarded as "abnormal cytosolic accumulation" of the antigens. This pattern was more pronounced in clear-cell carcinoma. Pretreatment of specimens with chloroform-methanol, which extracts glycolipids, decreased immunoreactivity in carcinoma tissues, particularly that in the cytosol. The extracts contained substances immunoreactive for MAb FH6. Our study has demonstrated that (a) remarkable changes occur in the ultrastructural localization patterns of sialyl Le(x)-i and Le(x) in renal cell carcinoma and (b) considerable amounts of glycolipids are contained in the substances with sialyl Le(x)-i deposited in the cytosol of clear-cell carcinoma.
Cell population of urinary leucocytes of 22 patients (intestine group) who underwent operations using intestinal segments for the urinary tract was compared with that of 26 complicated UTI patients without surgical intervention (control group). Eosinophils were recognized in 15.5 per cent of urinary leucocytes of the intestine group. However, in the control group, urine eosinophils were recognized only in 0.15 per cent. Although in sterile urines of the intestine group eosinophils were recognized in 30.8 per cent, in infected urines, the percentage of eosinophils decreased. Conversely, the percentage of neutrophils increased to 91.9 per cent. These findings suggest that neutrophils play an important role in infected urines of the intestine group as in urines of the control group. Significant differences were found in the values of urinary secretory IgA, IgG, IgM and urinary osmolarity. To evaluate the influence of these differences on the activity of phagocytosis of urinary leucocytes, the activity of phagocytosis of polymorphonuclear leucocytes (PMN), isolated from the peripheral blood, was investigated in immersion in urines of both groups. The mean rate of phagocytosis of E. coli in urines of both groups showed no statistically significant differences. However, urinary osmolarity of the intestine group was within the suitable range for phagocytosis and the activity of phagocytosis in urine was correlated with the value of IgG, which suggests that IgG has the opsonic effect. In contrast, the activity of phagocytosis in urine of the control group was strongly correlated with the value of urinary osmolarity. The growth of Providencia, Streptococcus, P. aeruginosa, whose frequency of isolation from urine of both groups was different in our previous study, and E. coli was studied in urine of the two groups. No significant difference in the growth of all bacteria was found, however. This finding suggests that the difference in the frequency of isolation of these bacteria from urine possibly depends on the adhesion of bacteria to intestinal epithelium.
Once a catheter has been passed into the bladder without contamination, there are several possible routes of subsequent infection during drainage period, such as: 1. Entry of bacteria alongside the catheter in the urethra. 2. Introduced bacteria adhered easily to the indwelling catheter and drainage system and colonized. 3. The catheter tip is covered rapidly by various nutrient materials which becomes a good culture medium of stuck bacteria, which is a supply source of bacteria into the bladder urine. 4. Although the motile bacilli ascend very slowly through the stagnant tube and no bacteria ascend against a slowly moving column, rapid transport of organisms occurs in the swirling fluid caused by the passage of rising air bubbles. 5. Continuous urethral catheter drainage permits an average residual urine volume of 7.3 ml. 6. The catheter destroys the antibacterial defense mechanisms of the urinary bladder. The reasons why in many cases of intermittent self-catheterization (CID) urine becomes sterile despite non-sterile procedure, are as follows. In addition to that CIC has none of the disadvantages of the indwelling catheter, it improves the vesical defense mechanisms deteriorated by high pressure voiding. The number of bacteria reintroduced during catheterization is relatively small and they can be eradicated by usual scheduled catheterization within 4-5 hours without residual urine. CIC must be started before trabeculation or diverticuli are formed, in which bacteria remain. Actual determination of residual urine volume after catheterization will help to prescribe a rational program of CIC.