ACTIVITY CONCENTRATIONS OF RADIOCAESIUM, 90SR AND 129I IN AGRICULTURAL CROPS COLLECTED FROM FUKUSHIMA AND REFERENCE AREAS IN JAPAN, AND INTERNAL RADIATION DOSES.

Significant quantities of radionuclides were released into the environment due to the 2011 TEPCO's FDNPS accident. Radiocaesium is the most important radionuclide for assessment of radiation dose, and small amounts of 90Sr and very long-lived radionuclide of 129I were also released into the environment. Spinach, potato and brown rice were collected from Fukushima, neighboring prefectures and reference areas of negligible deposition in 2018 and 2019. The activity concentration of 137Cs in crops in Hamadori (coastal side) was relatively higher than other areas. The activity concentration of 90Sr in the crops showed a similar range among four areas in Fukushima, and they were similar level of those collected throughout Japan. The activity concentration of 129I in the crops collected from Hamadori was higher than other Fukushima areas. However, the activity ratio of 129I/137Cs was lower by five to seven orders of magnitude. Internal radiation doses of radiocaesium for adult males from ingestion of local crops collected from Hamadori were 0.0046 mSv, and that of 129I were 0.00000045 mSv in 2019.

Development of In Vitro Endothelialised Stents - Review.

Endovascular treatment is prevalent as a primary treatment for coronary and peripheral arterial diseases. Although the introduction of drug-eluting stents (DES) dramatically reduced the risk of in-stent restenosis, stent thrombosis persists as an issue. Notwithstanding improvements in newer generation DES, they are yet to address the urgent clinical need to abolish the late stent complications that result from in-stent restenosis and are associated with late thrombus formation. These often lead to acute coronary syndromes with high mortality in coronary artery disease and acute limb ischemia with a high risk of limb amputation in peripheral arterial disease. Recently, a significant amount of research has focused on alternative solutions to improve stent biocompatibility by using tissue engineering. There are two types of tissue engineering endothelialisation methods: in vitro and in vivo. To date, commercially available in vivo endothelialised stents have failed to demonstrate antithrombotic or anti-stenosis efficacy in clinical trials. In contrast, the in vitro endothelialisation methods exhibit the advantage of monitoring cell type and growth prior to implantation, enabling better quality control. The present review discusses tissue-engineered candidate stents constructed by distinct in vitro endothelialisation approaches, with a particular focus on fabrication processes, including cell source selection, stent material composition, stent surface modifications, efficacy and safety evidence from in vitro and in vivo studies, and future directions.

Radiocaesium in the environment of Fukushima.

It has been 10 years since the accident at Fukushima Daiichi nuclear power plant in 2011. Large quantities of 131I, 134Cs, and 137Cs were released into the environment, and 80% of 137Cs still remains. In addition to the decrease by attenuation, the transfer of 137Cs to plants, animals, and humans is decreasing due to movement and changing fractions with elapsed time. The activity concentration of 137Cs in the atmosphere has decreased drastically, and the internal radiation dose due to inhalation is negligible. The activity concentration of 137Cs in agricultural plants is decreasing due to decontamination of soil, application of potassium, and lower levels in irrigation water. The activity concentration of 137Cs in wild animals is decreasing, and shows seasonal variation in wild boars. The activity concentration of 137Cs in offshore seawater has decreased to 0.01 Bq l-1. Therefore, the radiation dose is <1 mSv of the additional radiation dose.

Stimulatory effect of insulin on H+-ATPase in the proximal tubule via the Akt/mTORC2 pathway.

PURPOSE: Acid-base transport in renal proximal tubules (PTs) is mainly sodium-dependent and conducted in coordination by the apical Na+/H+ exchanger (NHE3), vacuolar H+-adenosine triphosphatase (V-ATPase), and the basolateral Na+/HCO3- cotransporter. V-ATPase on PTs is well-known to play an important role in proton excretion. Recently we reported a stimulatory effect of insulin on these transporters. However, it is unclear whether insulin is involved in acid-base balance in PTs. Thus, we assessed the role of insulin in acid-base balance in PTs. METHODS: V-ATPase activity was evaluated using freshly isolated PTs obtained from mice, and specific inhibitors were then used to assess the signaling pathways involved in the observed effects. RESULTS: V-ATPase activity in PTs was markedly enhanced by insulin, and its activation was completely inhibited by bafilomycin (a V-ATPase-specific inhibitor), Akt inhibitor VIII, and PP242 (an mTORC1/2 inhibitor), but not by rapamycin (an mTORC1 inhibitor). V-ATPase activity was stimulated by 1 nm insulin by approximately 20% above baseline, which was completely suppressed by Akt1/2 inhibitor VIII. PP242 completely suppressed the insulin-mediated V-ATPase stimulation in mouse PTs, whereas rapamycin failed to influence the effect of insulin. Insulin-induced Akt phosphorylation in the mouse renal cortex was completely suppressed by Akt1/2 inhibitor VIII and PP242, but not by rapamycin. CONCLUSION: Our results indicate that stimulation of V-ATPase activity by insulin in PTs is mediated via the Akt2/mTORC2 pathway. These results reveal the mechanism underlying the complex signaling in PT acid-base balance, providing treatment targets for renal disease.

Morphogenesis and development of microbodies of hepatocytes of rats during pre- and postnatal growth.

In hepatocytes of fetal rats, cytoplasmic organelles identifiable as microbodies appeared, although only a few of them showed nucleoids and most of them generally had an electronlucent appearance due to the low density of their matrices. Some of these microbodies, especially those lacking the nucleoid, showed a substantial connection with granular endoplasmic reticulum (ER), suggesting that microbodies might be formed from granular ER. Agranular tubular profiles projecting from the surface of microbodies were found with a high frequency in fetal and neonatal rats; however, this phenomenon may not provide crucial evidence suggestive of the derivation of microbodies from agranular ER. Growth and maturation of microbodies are considered to be brought about by an enlargement of these organelles, an increase in their matrices, an appearance and enlargement of the nucleoids, and an increase in the enzyme involved. The specific activity of urate oxidase in the isolated nucleoid fraction was significantly lower in the earlier stages of postnatal growth than later. Increases in the enzyme activity per nucleoid (maturation of the nucleoid), in the number of microbodies containing nucleoids (formation of the nucleoid), and in the size of nucleoids (growth of the nucleoid), may contribute to increases in the enzyme activity of the tissues.

The nucleoids of rat liver cell microbodies. Fine structure and enzymes.

The nucleoids of microbodies of rat liver cells were isolated in a highly homogeneous and pure state, by treating the microbody-rich fraction, prepared from 10% polyvinylpyrrolidone-0.25 M sucrose homogenate, with Triton X-100. Three treatments with 0.1% detergent were enough to render the nucleoids free from contamination with mitochondria, microsomes, lysosomes, and intact microbodies. Electron microscopically, the nucleoids were found to consist of parallel bundles of highly dense hollow tubules, the outer and inner diameters of which are approximately 150 and 50 A, respectively. Ten tubules are arranged around a longitudinal space 190 x 200 A in width. The nucleoids thus show a honeycomb appearance in the cross-plane and a parallel-packed structure in the longitudinal plane. Biochemically, the nucleoids were found to bear only urate oxidase among probably microbody-enzymes, and they might be the only cytoplasmic particles of rat liver cells in which the enzyme locates. Urate oxidase activity, on a unit protein basis, of the nucleoid preparation is approximately 380 times as high as that of the whole homogenate, and is almost comparable with that of a commercial type I enzyme preparation. No enzymes of mitochondrial, microsomal, and lysosomal origins were detected in the nucleoids. The fine structure of the nucleoids is described in detail, and a probable schematic diagram is presented.

Early recurrence after surgical resection in patients with pathological stage I non-small cell lung cancer.

INTRODUCTION: Early recurrence is observed even in patients who undergo complete resection and had pathological (p-) stage I. Therefore, we focused on early recurrence, and attempted to elucidate the relationship between early recurrence and clinicopathological factors. METHODS: Between May 1993 and December 2005, 1201 patients with non-small cell lung cancer (NSCLC) underwent surgical treatment at our institution. Of these, 402 patients who underwent complete resection and had p-stage I NSCLC were retrospectively analyzed for clinicopathological factors. Patients were divided into four groups according to the period between surgery and recurrence (R): no recurrence (NR, n = 331), late recurrence (LR, n = 28, R > 2 years), intermediate recurrence (IR, n = 22, 1 year < R < or = 2 years), and early recurrence (ER, n = 21, R < or = 1 year). RESULTS: The overall 5-year survival rate for patients with p-stage I was 79.9 %. The overall 5-year survival rates were 91.0 %, 55.6 %, 17.1 %, and 7.5 % for the NR, LR, IR, and ER group, respectively. Preoperative high CEA level, lymphatic permeation, and pleural invasion were proven to be independent factors for overall recurrence. Moreover, multivariate analysis showed that preoperative CEA level, pathological T factor, lymphatic permeation, vascular invasion, and pleural invasion influenced early recurrence within one year. CONCLUSIONS: The present study demonstrated that preoperative CEA level, pathological T-factor, lymphatic permeation, vascular invasion, and pleural invasion were independent prognostic factors for early recurrence within one year, even in patients with pathological stage I. In patients with these factors, adjuvant therapy may be indicated since this may improve their survival.

SPECIATION OF IODINE IN SOIL SOLUTION IN FOREST AND GRASSLAND SOILS IN ROKKASHO, JAPAN.

The behaviour of I in soil depends on its chemical form in soil solution. Stable I (127I) in the soil solution under actual soil conditions was investigated as a natural analogue of long-lived radioiodine (129I). Soil samples were collected at 5-cm depth intervals down to 20 cm from forests and grasslands in Rokkasho, where the Japanese first commercial nuclear fuel reprocessing plant is located, and the soil solution was extracted by centrifugation. Almost half of total I in the soil solution was iodide, and the other half was dissolved organic I (DOI), with iodate under the detection limit. The proportion of DOI in total I at 0-5 cm depth was larger than the proportions at 5-20 cm depth. The concentration of DOI was positively correlated with that of DOC in the soil solution, suggesting that the behaviour of DOI in the surface soil is affected by labile organic matter dynamics.

[Surgical outcome of tracheobronchial reconstruction for lung cancer].

We retrospectively evaluated the surgical outcome after sleeve lobectomy and pneumonectomy with tracheobronchial reconstruction for lung cancer. From 1993 to 2008, 46 patients with primary lung cancer underwent these surgical procedures. Seventeen patients (37%) received induction therapy, 15 received chemotherapy, while chemoradiotherapy or radiotherapy alone were received by one patient each. Sleeve lobectomy without carinal resection was performed in 41 patients. Carinal resection with 2 sleeve pneumonectomies was performed in 5 patients. There were no operative deaths. Bronchopleural fistula occurred in one patient, who required completion pneumonectomy. One patient presented local mucosal necrosis in the anastomotic site and was managed conservatively. Two patients had bronchial strictures as late complications and successfully dilated by a balloon using bronchoscopy. Overall 5-year and 10-year survival rates were 54% and 48%, respectively. No recurrence developed at any anastomotic site. The results showed that sleeve lobectomy and pneumonectomy with tracheobronchial reconstruction can be performed with low mortality and bronchial anastomotic complication rates. As well, local control of the tumor was satisfactory.

Soluble complex of complement increases hydraulic conductivity in single microvessels of rat lung.

We determined the effect of sera enriched with the soluble complex of complement (SC5b-9), on hydraulic conductivity (Lp) of single pulmonary venules (diameter 20-30 microns). Sera free of anticoagulants and blood cells were prepared from rat and human blood. Lp were determined by our split drop technique in isolated, blood-perfused lungs prepared from anesthetized rats (2% halothane; Sprague Dawley, 500 g; n = 73). Zymosan-activated (ZAS) and control sera were used for Lp determinations. In ZAS prepared from human serum, SC5b-9 concentration was > 300 micrograms/ml (control: < 1 microgram/ml) as determined by ELISA. At baseline, Lp averaged 3.4 +/- .4 x 10(-7) ml/(cm2.s.cm H2O), but it increased by 217 +/- 32% with undiluted ZAS (P < 0.05). The Lp increase correlated significantly with different ZAS dilutions for rat serum and with SC5b-9 concentration for human serum. Lp did not increase significantly with ZAS prepared from heat-treated sera, C6- and C8-deficient sera; or with ZAS in which SC5b-9 had been depleted by immunoprecipitation. The ZAS-induced increase of Lp was blocked completely by venular preinfusion with the arginine-glycine-aspartic acid (RGD) tripeptide (1 mg/ml, 10 min). We report for the first time that: (a) SC5b-9 increases lung endothelial Lp; and (b) the increase of Lp is attributable to an integrin-dependent mechanism.

In vitro measurement of resistance to phalloidin and gamma-glutamyltransferase of carcinogen-induced preneoplastic hepatocytes of rats.

Male inbred F344 rats weighing about 150 g were fed continuously a diet containing 0.02% N-2-fluorenylacetamide for 14-15 weeks. The presumptively preneoplastic hepatocytes were transferred to an in vitro system after dispersion by a collagenase-perfusion technique. Sensitivity to phalloidin in terms of formation of cytoplasmic blebs on the cell surface was less in the presumptively preneoplastic hepatocytes than in normal hepatocytes. Among the presumptively preneoplastic hepatocytes, the gamma-glutamyltransferase (GGT)-positive cells were less sensitive to phalloidin than GGT-negative cells, indicating a greater contribution to the decrease in the sensitivity to phalloidin of the presumptively preneoplastic cells.

Matrical inclusions induced by clofibrate in hepatic microbodies of rats fed 2-acetylaminofluorene.

Abnormal inclusions in microbodies were induced by clofibrate in hepatocytes of hyperplastic liver nodules in rats fed 2-acetylaminofluorene. These were matrical tubules and plates, each with the same ultrastructural features as those reported previously by other investigators. A hyperplastic state of hepatocytes induced by hepatocarcinogens might be related to the formation of these inclusions in response to clofibrate.

Response of microbodies in Morris hepatoma 9618A to clofibrate.

Regulation of the formation of microbodies in Morris hepatoma 9618A was studied by examination of the response of the organelles to clofibrate. The fine structures of microbodies in the hepatoma cells closely resembled those in hepatocytes of normal adult rats. In clofibrate-treated rats, the tumor cells showed a slight increase in the size of microbodies and in catalase activity; however, the tumor microbodies did not increase in number. In contrast, in adult clofibrate-treated rats and rats on the day of birth whose mothers received clofibrate during the gestation period, the hepatocytes showed microbodies that were greater in both number and size, and the catalase activity in the liver was definitely elevated.

Changes in peroxisomes in preneoplastic liver of rats induced by 3'-methyl-4-dimethylaminoazobenzene.

Histochemical investigations used the 3,3'-diaminobenzidine reaction to demonstrate the catalase activity and thus variations in numbers of peroxisomes, and electron microscopic examinations were made of hyperplastic liver lesions in rats fed 0.06%3'-methyl-4-dimethylaminoazobenzene. At the 10th week of carcinogen feeding, hyperplastic lesions (hyperplastic foci, areas, and nodules) appeared and advanced to further stages. Most of the foci and some of the areas and nodules showed very low catalase activity and, correspondingly, a small number of peroxisomes. When rats were administered ethyl-alpha-p-chlorophenoxyisobutyrate, most of the foci, areas, and nodules showed a moderate increase in catalase activity and in peroxisome number. Hyperplastic foci seemed to grow larger with time to form hyperplastic areas and/or nodules, mostly accompanying maturation as well as proliferation of the hepatocytes involved. Maturation is well characterized by an increase in the endogenous level of catalase and in the number of peroxisomes, as well as by an enhancement of the responsiveness to ethyl-alpha-p-chlorophenoxyisobutyrate. However, there was a small proportion of lesions in which all cells or some cells did not mature and thus were considered persistently altered. It is suggested that these altered cells serve mainly as intimate precursors of hepatomas.

Changes in peroxisomes in preneoplastic liver and hepatoma of mice induced by alpha-benzene hexachloride.

Peroxisomes in hepatomas and hyperplastic preneoplastic liver lesions induced in mice by 500 ppm alpha-benzene hexachloride were examined histochemically and electron microscopically. Although most of the hepatomas were well-differentiated tumors and contained a considerable number of peroxisomes, the tumor cells did not respond to ethyl-alpha-p-chlorophenoxyisobutyrate with proliferation of peroxisomes. At the 16th week of carcinogen feeding, hyperplastic nodules appeared and advanced to further stages. A majority of the nodules showed a considerable number of peroxisomes and the inductive proliferation of peroxisomes. Within the nodules, foci of proliferation of the cells that showed no inducibility of proliferation of peroxisomes appeared. These cells proliferated further, replacing the most part of the nodules, and with this process hepatomas appeared to have been formed. No abnormal matrical inclusions of peroxisomes were formed in the cells of hyperplastic nodules by ethyl-alpha-p-chlorophenoxyisobutyrate unlike in the case of rats.

Tumor cells with organ-specific metastatic ability show distinctive trafficking in vivo: analyses by positron emission tomography and bioimaging.

To elucidate the behavior of various metastatic tumor cells with different characteristics in the blood flow, we have developed a system to investigate real-time trafficking using positron emission tomography. In this study, positron-labeled cells, i.e., lung-metastatic B16BL6 melanoma and two sublines of liver-metastatic RAW117 large cell lymphoma, were injected i.v., and the trafficking of these cells was noninvasively determined. All sublines tested accumulated in the lungs immediately after injection, presumably because the lungs were the first organ passed through after i.v. injection. The elimination of RAW117 cells from the lungs, however, was fast compared with that of B16BL6 cells. The latter showed a release rate from the lungs of less than 1%/min, whereas that of RAW117 cells was greater than 2%/min. Reflecting the elimination from lungs, RAW117 cells accumulated in the liver in a time-dependent manner. Biodistribution of metastatic cells was also analyzed by whole-body autoradiography after injection of 5-[125I]iodo-2'-deoxyuridine-labeled cells, using a bioimaging analyzer system. The method is invasive; however, it enables a precise determination of the biodistribution of metastatic cells. Bioimaging analyzer system analysis also showed the organ-specific accumulation of these metastatic cells. Furthermore, colonized distribution of B16BL6 cells in the lungs and that of RAW117 cells in the liver were observed. The present data suggest that the trafficking of metastatic tumor cells greatly influences the organ specificity of cancer metastasis.

Positron emission tomography analysis of metastatic tumor cell trafficking.

Organ-specific colonization of metastatic tumor cells is regulated through complex interactions of specific adhesion molecules on the tumor cell surface with organ specific microvascular endothelium. The present paper shows the real time tumor cell trafficking under the actual blood flow, which became able to be determined using a new technology, positron emission tomography. This technology would be useful to evaluate the interaction of characteristic tumor cells with various organs in vivo. High and low metastatic rat mammary adenocarcinoma cell variants, MTLn3 and MTC, respectively, were labeled with [2-18F]2-fluoro-2-deoxy-D-glucose in vitro. The labeled cells preferentially accumulated in the lungs, in which the disposition was more intense for MTLn3 than for MTC cells especially for the first 2-10 min after injection, apparently reflecting the organ specific interaction of metastatic tumor cells which may lead to metastasis. Such a short time change of cell disposition is easily determined in a living animal by this new technique. Furthermore, sialidase treatment of MTLn3 cells suppressed the accumulation of these cells in lungs, suggesting that some sialyl glycoconjugates on the MTLn3 cell surface play an important role in cell adhesion to lung endothelium. Positron emission tomography scanning thus enables the noninvasive study of the interaction of characteristic tumor cells with specific endothelium in a living animal.

Real-time analysis of liposomal trafficking in tumor-bearing mice by use of positron emission tomography.

Long-circulating liposomes are known to accumulate passively in tumor tissues of tumor-bearing animals. To evaluate the in vivo behavior of such liposomes, we investigated the real-time liposomal trafficking by a non-invasive method using position emission tomography (PET). Liposomes composed of dipalmitoylphosphatidylcholine, cholesterol, and palmityl-D-glucuronide (PGlcUA) in a molar ratio of 4:4:1 were prepared in the presence of 2-[18F]fluoro-2-deoxyglucose ([2-18F]FDG). [2-18F]FDG-labeled liposomes sized by extrusion through a filter with various-sized pores were administered to mice bearing Meth A sarcoma, and a PET scan was performed for 120 min. Small-sized, long-circulating liposomes (100 nm in diameter) constructed with PGlcUA tended to accumulate in the tumor tissues. On the contrary, control liposomes (100 nm in diameter) containing dipalmitoylphosphatidylglycerol instead of PGlcUA accumulated in the liver. Large-sized PGlcUA-containing liposomes (> 300 nm) also accumulated in the liver, as well as in the spleen. Time-activity curves indicated that the small long-circulating liposomes (< 200 nm) transiently accumulated in the liver right after the injection but that the accumulation there decreased time-dependently. These data suggest that, although the majority of small long-circulating liposomes remain in the bloodstream, some extravasate once into the interstitial spaces in the liver re-enter the bloodstream again, and finally accumulate in the tumor tissues. This PET technique might be useful for studying real-time liposomal trafficking and for tumor imaging.

Real-time PET analysis of metastatic tumor cell trafficking in vivo and its relation to adhesion properties.

Although a number of studies have indicated that highly metastatic cells tend to adhere more to target endothelium in vitro than low or non-metastatic cells, direct evidence about the correlation between cellular adhesiveness and organ disposition of the cells has not been obtained. Using positron emission tomography (PET), we have developed a novel technique that enables the non-invasive detection of the real-time tumor cell trafficking. The present study shows the correlation between trafficking of murine large cell lymphoma RAW117 and the adhesion properties of the cells in vitro. Cells accumulated in the liver time-dependently, and accumulation of RAW117-H10, liver metastatic subline cells, was more intense than that of RAW117-P, the parental cells, indicating that the metastatic potential is correlated with the in vivo accumulation of the cells in the target tissue. To examine whether the adhesion properties of the cell membrane determine the cell trafficking, we performed PET analysis after altering the adhesion properties on the cell membrane by means of cellular protein kinase C modulation, since the modulation of this enzyme is known to alter the surface adhesion molecules, i.e., those of the integrin superfamily. The treatment of RAW117-P with 12-O-tetradecanoylphorbol 13-acetate, which caused augmentation of adhesion to hepatic sinusoidal microvessel endothelial cells (HSE) in vitro, enhanced the hepatic accumulation of the cells in vivo. On the contrary, treatment of RAW117-H10 with the protein kinase C inhibitor H-7, 1-(5-isoquinolinesulfonyl)-2-methylpiperazine dihydrochloride, which reduced the adhesion activity of the cells to HSE, suppressed their accumulation in the liver, although the suppression was observed only during the first 30 min after administration of the cells. These data suggest that the adhesion properties of metastatic lymphoma cells are critical for the accumulation of these cells in the target tissue.

Effect of serum protein binding on real-time trafficking of liposomes with different charges analyzed by positron emission tomography.

Liposomes have been used as carriers of various materials and as tools for gene transfer: for the latter purpose, positively charged liposomes are usually used. To evaluate the stability in the presence of serum and the in vivo behavior of such liposomes as well as those aspects of neutral and negatively charged liposomes, we investigated liposomal agglutinability in the presence of serum, serum protein binding to these liposomes, and real-time liposomal trafficking by a non-invasive method using positron emission tomography (PET). Liposomes composed of dipalmitoylphosphatidylcholine, cholesterol without or with charged lipid were prepared in the presence of mannitol, and the turbidity change in the presence of serum was determined. Turbidity increase was not observed for so-called long-circulating liposomes, i.e., liposomes modified with glucuronic acid or with poly(ethylene glycol), or for negatively charged liposomes containing dicetyl phosphate (DCP), phosphatidylglycerol, or phosphatidylserine. On the contrary, a significant turbidity increase was observed when positively charged liposomes modified with stearylamine, stearyltrimethylammonium chloride or 1,2-dimyristyloxypropyl-3-dimethylhydroxyethyl bromide (DMRIE), which is known as a component of liposomes for gene transfer, were used. These liposomes were found to have bound a high amount of serum proteins after separation of unbound serum proteins by use of a spin column. The liposomal trafficking in vivo was determined for three kinds of liposomes, i.e., liposomes with DMRIE, those with DCP, and those without charged lipids. These liposomes were prepared in the presence of 2-[18F]fluoro-2-deoxy-D-glucose ([2-18F]FDG), and the [2-18F]FDG-labeled liposomes were administered to mice to perform PET scans. Positively charged liposomes containing DMRIE showed high accumulation in the liver compared with neutral and negatively charged liposomes. Since DMRIE-liposomes tended to aggregate in the presence of serum, and to be associated with serum protein, these characteristics may lead to the high uptake of DMRIE-liposomes by the liver.