Sequential loss-on-ignition as a simple method for evaluating the stability of soil organic matter under actual environmental conditions

Soil organic matter (SOM) is one of the largest carbon (C) reservoirs on Earth, and therefore its stability attracts a great deal of interest from the perspective of the global C cycle. This study examined the applicability of loss-on-ignition with a stepwise increase in temperature (SIT-LOI) of soil to evaluate the stability of SOM using soil samples having different organic matter (OM) and mineral contents and different mean residence times (MRTs) for SOM. The responses of SOM to the SIT-LOI varied depending on the samples but were all successfully approximated by a liner regression model as a function of the temperature of LOI. The slope value in the liner model that determines the residual potential of carbon during the SIT-LOI highly correlated with MRT of SOM, suggesting that this value reflects the overall stability of SOM over a range of soil properties. This hypothesis was consistent with the observation that Δ14C values of SOM decreased with increasing LOI temperature and thus, older, slower-cycling SOM was preferentially left in the soil samples by SIT-LOI. Additionally, the hypothesis was also supported by the significant correlations (p < 0.01) between the slope value and OM and mineral contents in the samples because these components are considered to regulate SOM stability. In addition to the regression analysis of the SIT-LOI data, changes in carbon to nitrogen (C/N) and carbon to hydrogen (C/H) ratios and stable carbon isotope signatures (δ13C) of the samples were investigated. The results suggest that the mineral association of SOM is an important factor characterizing the response of SOM to LOI. Hence, it was concluded that SIT-LOI is a simple and useful method for evaluating the stability of SOM under actual environmental conditions.

Evaluating production rates of particulate organic hydrogen by marine phytoplankton for estimating phytoplanktonic productivity of organically bound tritium

To estimate the production potential of organically bound tritium (OBT) by phytoplankton from tritiated water in coastal areas adjacent to the Fukushima Daiichi Nuclear Power Plant (FDNPP), phytoplanktonic production rates of particulate organic hydrogen (POH) were evaluated in laboratory and field experiments using stable isotope tracers (2H and 13C). In the laboratory experiment, the production rate of POH was evaluated for five types of phytoplankton cultivated cultures (two diatoms, Haptophyceae, Chlorophyceae, and Cryptophyceae) at two temperatures (15 °C and 25 °C) and two 2H concentrations in the medium (1 and 5%). Additionally, the production rate of POH was especially focused on non-exchangeable POH (NE-POH) which is the chemical form of hydrogen connected tightly to organic matter. The production rates of NE-POH in the laboratory experiment varied (0.10 to 36 μmol L-1 d-1 μg-Chl a-1) with the productivity of particulate organic carbon, phytoplankton species, and temperature, with negligible influence of 2H concentrations. In the field experiment, in situ incubation of coastal seawater at water depths of 1 and 20 m with isotope tracers under light and dark conditions, respectively, was performed thrice (November 2021, May 2022, and October 2022) on the Pacific coastal ocean approximately 2 km from the land of northeast Japan. We observed variation in the production rate of POH (0.21 to 3.1 μmol L-1 d-1 μg-Chl a-1), which was theoretically explained by the data in the laboratory experiment. Using the phytoplanktonic production rate of POH obtained in this study, OBT production by phytoplankton and the subsequent accumulation potential of OBT in sediments in the coastal area adjacent to FDNPP were tentatively estimated, results of which suggested this potential to be small.

Investigation of changes in the iodine concentrations of oceanic sediment and terrestrial soil samples after thermal drying

To certify the suitability of pretreatment by thermal drying to measure iodine concentrations of oceanic sediment and terrestrial soil samples, changes in iodine concentrations after drying (50, 80 or 85, and 110 °C for 48 h) were examined using the samples in addition to a terrestrial plant (pine needles), which was selected as an intact organic sample. The iodine concentrations per wet weight of the sediment and soil samples processed by thermal drying were comparable to those of the raw samples at all temperatures. However, the concentrations of the plant samples dried at 85 and 110 °C were lower than those of the raw samples. The lower concentrations of the plant samples at higher temperatures were considered to be derived from the volatilization of a part of the plant's organic matter. Finally, these results suggested that the iodine concentrations in oceanic sediment and terrestrial soil samples scarcely change after thermal drying at 110 °C, although the concentrations may decrease when these samples include high contributions of fresh organic matter.

Organic matter composition regulates residual potential of organic carbon of the seagrass Zostera marina L. during its decomposition process in seawater

Although the seagrass Zostera marina L. (Z. marina) is expected to significantly contribute to environmental carbon dynamics, the residual potential of organic carbon (Corg) in this plant during its decomposition process in seawater remains insufficiently understood. In this study, the factors regulating this potential were examined by evaluating Z. marina decomposition in seawater and conducting a multiple regression analysis on data from the experiment as well as the original plant organic matter composition. The residual ratio during the decomposition experiment (RDEC) of carbon in Z. marina for 111 days ranged from 0.30 to 0.84 (n = 16), and the variation resulted from differences in the sampling season of this plant. Regression analysis was conducted to explain the RDEC of carbon using the RDEC of nitrogen, concentrations of carbon, nitrogen, HCl-extractable Corg and nitrogen, contributions of carbohydrate (CCAR) of total and non-structural fractions and lipid (CLIP) to carbon concentration. The RDEC of carbon was most adequately fitted using a multiple regression including three parameters, carbon concentration, CLIP, and CCAR of total carbohydrate with a significant determination coefficient. The former two parameters (carbon concentration and CLIP) have negative coefficients, indicating that these parameters correspond to bacterially available Corg in Z. marina in the regression analysis. The latter parameter (CCAR of total carbohydrate) shows a positive coefficient that indicates recalcitrant Corg in the regression. Parameters related to nitrogen were not included in the regression formula, although this element is reportedly an important parameter regulating the environmental decomposition rate of Corg. Finally, we suggested that total carbon, carbohydrate, and lipid are especially important factors to regulate the environmental residual potential of Z. marina Corg among organic components of this plant.

EXPERIMENTAL EVALUATION OF DISTRIBUTION OF 14C PHOTOASSIMILATED INTO CARBOHYDRATES IN DIFFERENT GROWTH STAGES OF FRUIT-BEARING APPLE SHOOTS USING A 13CO2 IN-SITU EXPOSURE SYSTEM

In this study, we aimed to investigate the photoassimilation process of 14CO2 into agricultural plants through determining the photoassimilated carbohydrate-13C in each part (leaves, current branch and fruit) of the fruit-bearing apple shoots exposed to 13CO2 in different growth stages (early and late fruit development stages). The carbohydrate content was assessed as soluble (ethanol-extracted fraction) and other (HCl-extracted and residual fractions) components. The total (i.e. sum of the three fractions) bulk carbohydrate concentrations in all parts of the shoots were statistically similar between different growth stages. The changes in the concentration of 13C-labeled soluble carbohydrate (i.e. ethanol-extracted fraction) to the total content between different growth stages were statistically unclear among all parts of the shoot. These results suggest that the distribution ratio of photoassimilated 13C in soluble and other components in the apple shoot was thereabout constantly independent of the growth stages.

Investigation of ratio of carbon to hydrogen (C/H ratio) in agricultural plants for further estimation of their productivity of organically bound tritium

The carbon to hydrogen ratio (C/H ratio, w/w) in plants is a key factor in estimating the amount of hydrogen in the photosynthetic product. The amount of hydrogen calculated from photosynthetic model estimation associated with the C/H ratio is an essential parameter of the estimation model of productivity of organically bound tritium (OBT) by plants. To propose a sophisticated estimation model of OBT by agricultural plants, temporal changes in the C/H ratio of six plant species (Japanese radish, cabbage, orchard grass, paddy field rice, apple, and radish) during their cultivation were investigated for each plant part. The C/H ratio in the plants cultivated in the field and growth chamber generally exceeded 6, which is the value for the primary photosynthetic monosaccharides, such as glucose and fructose (both chemical formulae, C₆H₁₂O₆). In the vegetative parts (e.g. Japanese radish leaves, cabbage leaves and roots, rice leaves and roots, and radish leaves and fine roots) the C/H ratio fluctuated irregularly or remained constant within an approximate range of 6.6-7.3 during cultivation. The C/H ratio in enlarged organs (e.g. Japanese radish root, rice ear, apple fruit, and radish main root) decreased continuously, approaching 6. These results suggest that the C/H ratio can be generally set as approximately 6.9 except for enlarged organs, in which the ratio may change over time during cultivation, within an approximate range of 6-7.

Flux and pathway of iodine dissolution from brackish lake sediment in the northeast of Japan

Sediment is one of the most important entities controlling the environmental dynamics of iodine. We previously evaluated the dissolution flux of iodine from aquatic sediment to its overlying water in a brackish lake through an incubation experiment with a sediment core sample, reporting the regulation factors of this flux, such as the temperature and oxygenic conditions. In this study, factors controlling the seasonal variation in the dissolution flux of iodine were investigated via an incubation experiment using the sediment core samples collected in autumn and summer. The dissolution flux in this study was significantly smaller than that reported in our previous study. The iodine concentration detected in the overlying water of the sediment during incubation in this study was positively correlated with the concentrations of some inorganic ions, such as Na⁺, Cl^-, and SiO₄^2-, while these correlations were not confirmed in our previous study. As the dissolution of sedimentary iodine includes two pathways, which are the diffusion of sedimentary pore water and degradation of organic matter on surface sediment, correlations potentially indicate that the dissolution flux estimated in this study has a larger contribution from sedimentary pore water than that in our previous study. In addition, the higher flux estimated in our previous study was considered to be caused by the larger contribution from iodine derived from the degradation of phytoplanktonic organic matter on surface sediment. Assuming that the dissolution fluxes estimated in the previous and present studies are representative of the fluxes during and excluding the high productivity season in Lake Obuchi, respectively, we estimated the annual flux at 2.7 g y^-1 m^-2, which is comparable with our previous estimation.

Evaluation of radioiodine (129I) dissolution from sediment of a brackish lake beside a spent nuclear fuel reprocessing plant in Japan

Dissolution fluxes of stable (¹²⁷I) and radioactive (¹²⁹I) isotopes of iodine from a brackish lake sediment beside a spent nuclear fuel reprocessing plant in Japan were evaluated through two kinds of experiments: incubation using a sediment core sample for 24 h, and observation of ¹²⁷I and ¹²⁹I concentrations in sedimentary pore water. For ¹²⁷I, the dissolution flux evaluated in the incubation experiment was comparable with that obtained from the vertical gradient of ¹²⁷I concentration in pore water in the observation experiment. This suggests that degradation of organic matter in the surface sediment is an important source of dissolved ¹²⁷I found in the water. For ¹²⁹I, the dissolution flux estimated in the incubation experiment showed negative values, indicating the transfer of ¹²⁹I to the sediment from the overlying water (i.e., absorption). Moreover, the flux evaluated from the observation experiment was positive. This result suggests that degradation of organic matter in the surface sediment is scarcely important to the supply of ¹²⁹I from the sediment to the water in the studied lake. The dissolution flux of ¹²⁹I estimated in the observation experiment was smaller than the absorption flux of ¹²⁹I in the incubation experiment. This potentially indicates that the dissolution of sedimentary ¹²⁹I does not significantly change ¹²⁹I concentrations in the water and sediment of the lake. This hypothesis was consistent with previous research conducted for the studied lake.

Evaluation of dissolution flux of iodine from brackish lake sediments under different temperature and oxygenic conditions

Dissolution flux of iodine from aquatic sediments in a brackish lake (Lake Obuchi), facing the Pacific Ocean and adjacent to a nuclear fuel reprocessing plant in northeast Japan, was evaluated using incubation experiments on sediment core samples. The experiments were performed under three different temperatures (29, 17, and 6 °C) and oxygenic (air flow, N₂ gas flow, and untreated) conditions for 48 h. The total dissolved iodine (TDI) concentration (i.e., the sum of iodide, iodate, and dissolved organic iodine, DOI) increased under all temperatures and oxygenic conditions in the first 6 h of incubation. From 6 to 27 h, noticeable increases in TDI concentration only occurred at high temperatures. Dissolution fluxes of iodine estimated by linear regression analysis of the measured TDI concentration in the first 6 h were always higher than those estimated in the first 27 h. This result indicates that dissolution flux of iodine should be evaluated through short-term (within several hours) incubation experiments because absorption reactions which transport iodine from the overlying water back to the sediment become active in the long-term. No substantial difference in dissolution flux, estimated by TDI concentration, was observed under different oxygenic conditions in the first 6 h. However, dissolution flux increased significantly with an increase in temperature. Increases in flux and temperature were significantly and positively correlated (R² = 0.90), suggesting that temperature was the dominant factor that regulated iodine flux during the incubation. Changes in TDI concentration at all temperatures and oxygenic conditions corresponded to those in iodide concentration, indicating that iodide was the main form of iodine dissolved from the sediments. In later stages of the experiments, from 27 to 48 h, the TDI concentration in overlying water increased only at high temperature, while concentrations at medium and low temperatures remained constant or decreased. In particular, oxic experiments showed substantial decreases in iodide concentration at medium and low temperatures. This suggests that oxic conditions promote the absorption of iodine from the overlying water to the sediments. Finally, the dissolution flux of radioiodine (iodine-129) from the sediments of Lake Obuchi to the overlying water was estimated by combining these results with data from earlier studies. The results suggest that only 0.006% of the iodine-129 accumulated in the sediments is released through dissolution to the overlying water per year, suggesting that this radioactive isotope is essentially stable in the sediments.

Concentrations of iodine-129 in coastal surface sediments around spent nuclear fuel reprocessing plant at Rokkasho, Japan, during and after its test operation

Concentrations of 129I in coastal surface sediment samples from the east coast of Aomori, Japan, 2–65 km away from the wastewater outlet of the nuclear fuel reprocessing plant at Rokkasho, Japan, were measured from 2006 to 2010. No clear effect on 129I/127I atom ratios in marine sediments was observed, although 129I was discharged from the plant, during its test operation using actual spent fuel, mainly between 2006 and 2008. The ratio in sediments collected at a fishing port at the mouth of a brackish lake increased in 2007, showing that the 129I migrated from the lake to the port.

P737Endothelial ERK2/thromboxane receptor pathway induces endothelial dysfunction, insulin resistance and steatohepatosis through superoxide with high fat high sucrose diet

Introduction

Metabolic syndrome (MetS) is well known as the risk of cardiovascular diseases associated with endothelial dysfunction and induces steatohepatosis. Insulin resistance is a major character of MetS, which affects intracellular signaling pathways and endothelial function. Extracellular signal-regulated kinase (ERK) is a major component of insulin signal and many of vasoactive peptides, which were released in MetS, can activate it in endothelium. However, the role of endothelial ERK in nitric oxide (NO) bioactivity in MetS in in vivo has been unknown.

Purpose

The aim of this study is to clarify the role of endothelial ERK2 on NO bioactivity in mice model of MetS.

Methods and results

We created endothelial specific ERK2 knock out mice (EE2KO) crossing Tie2-Cre mice and ERK2 flox mice and fed them with normal or high-fat/high-sucrose diet (HFHSD) for 24 weeks. Serum glucose and insulin levels and HOMA-IR were lowered in EE2KO with HFHSD without changing body weight. In wild type mice (WT) with HFHSD, nonalcoholic fatty liver disease (NAFLD) activity score, fibrosis score and serum ALT level were increased, all of which were blunted in EE2KO. EE2KO with HFHSD lowered systolic blood pressure (WT: 123.7±5.83 mmHg, EE2KO: 101.4±3.66 mmHg, P<0.01, N=8) without changing heart rate, which was increased to the same levels with L-NAME, an endothelial NO synthase inhibitor, in both groups. Serum NO levels measured with serum nitrite/nitrate concentrations were increased in EE2KO with HFHSD (WT: 23.10±3.74 μmol/l, EE2KO: 41.71±6.73 μmol/l, P<0.05, N=12). Endothelial function was assessed with the isometric tension measurement of aortic rings with acetylcholine (ACh). ACh-induced relaxation was improved in EE2KO with HFHSD. Superoxide production of aorta from EE2KO was lowered than WT with HFHSD in dihydroethidium (DHE) staining. S18886, an antagonist of the thromboxane A2-prostanoid (TP) receptor, decreased superoxide production of aorta in DHE staining resulting in improving endothelial function in the isometric tension measurement of aortic rings. Oral administrations of S18886 decreased systolic blood pressure, serum fasting glucose and insulin levels, and surprisingly improved steatohepatosis by decreasing NAFLD activity score and fibrosis score.

Relaxation of aortic rings with ACh

Conclusions

Endothelial ERK2/TP receptor pathway increases superoxide production and decreased NO bioactivity, resulting in deteriorating endothelial function, insulin resistance and steatohepatosis, which were improved by antagonist of the TP receptor in mice model of MetS. The present study indicates that ERK2/TP pathway could be a therapeutic target for complications of MetS.

Concentrations of iodine-129 in livestock, agricultural, and fishery products around spent nuclear fuel reprocessing plant in Rokkasho, Japan, during and after its test operation

Concentrations of iodine-129 (129I) and atomic ratios of 129I/127I in livestock (grass and milk), agricultural (cabbage, Japanese radish, and rice), and fishery (flatfish and brown alga) products collected from locations around the first Japanese commercial spent nuclear fuel reprocessing plant in Rokkasho were measured from 2006 to 2016. The actual spent nuclear fuel rods were cut and processed to test the functioning of the plant that discharged controlled amounts of 129I to the atmosphere and coastal seawater during the period from 2006 to 2008 (the "cutting period"). Statistically significant increases in 129I concentration and 129I/127I ratio were observed during the cutting period in livestock products and flatfish. On the other hand, these parameters were statistically comparable during and after the cutting period in the other products. The radiation dose through the ingestion of the maximum 129I concentrations, measured in the different products, was estimated to be in the nanoSievert per year level. This value is much smaller than 1 mSv yr-1, which is the permissible authentic radiation dose for the general public. The 129I levels in the samples, especially in milk and flatfish, are discussed in context of the 129I discharge history from the plant.

Routine Referral by Urologists Increase Opportunities for Corneal Donation

BACKGROUND

The levels of corneal donation are insufficient to meet the demand for corneal transplantation in Japan. To overcome this problem, we started to routinely mention the possibility of corneal donation to the families of patients who died in our hospital's Urology Department in February 2008. In this study, we evaluated the effectiveness of this approach.

METHODS

We retrospectively reviewed the medical records of the patients who died in the Department of Urology, St. Marianna University School of Medicine Hospital, and analyzed the patients' characteristics and information about corneal donation.

RESULTS

In total, 211 patients died in our department between February 2008 and March 2017, and 155 patients were medically suitable corneal donors. We mentioned the possibility of corneal donation to 129 (83.2%) families, and 29 (18.7%) families agreed. Three families subsequently withdrew their consent. Finally, 26 (16.8%) of the families that were approached about corneal donation by urologists agreed to donate their relatives' corneas. Another 2 families voluntarily offered to donate their relatives' corneas. Thus, 28 (18.1%) of 155 medically suitable donors donated their corneas for transplantation. Twenty-six (92.8%) donors were 60 years or older and all donors were affected with malignant genitourinary tumors. Fifty-four (96.4%) corneas were successfully transplanted into recipients.

CONCLUSIONS

Even elderly patients who die of solid carcinoma can be an important source of corneal donors. In this study, we showed that routine referral by urologists increased corneal donation. If this approach were adopted by other departments, it might further increase the number of corneal donations.

Distribution and fate of 129I in the seabed sediment off Fukushima

In this study, seabed sediment was collected from 26 stations located within 160 km from the Fukushima Dai-ichi Nuclear Power Plant (FDNPP) during the 2 years which followed the FDNPP accident of March 2011 and the concentrations of ¹²⁹I and ¹³⁷Cs were measured. By comparing the distribution of these two radionuclides with respect to their different geochemical behaviors in the environment, the transport of accident-derived radionuclides near the seafloor is discussed. The concentration of ¹²⁹I in seabed sediment recovered from offshore Fukushima in 2011 ranged between 0.02 and 0.45 mBq kg^-1, with ¹²⁹I/¹³⁷Cs activity ratios of (1.9 ± 0.5) × 10^-6 Bq Bq^-1. The initial deposition of ¹²⁹I to the seafloor in the study area was 0.36 ± 0.13 GBq, and the general distribution of sedimentary ¹²⁹I was established within 6 months after the accident. Although iodine is a biophilic element, the accident-derived ¹²⁹I negligibly affects the benthic ecosystem. Until October 2013, a slight increase in activity of ¹²⁹I in the surface sediment along the shelf-edge region (bottom depth: 200-400 m) was observed, despite that such a trend was not observed for ¹³⁷Cs. The preferential increase of the ¹²⁹I concentrations in the shelf-edge sediments was presumed to be affected by the re-deposition in the shelf-edge sediments of ¹²⁹I desorbed from the contaminated coastal sediment. The results obtained from this study indicate that ¹²⁹I/¹³⁷Cs in marine particles is a useful indicator for tracking the secondary transport of accident-derived materials, particularly biophilic radionuclides, from the coast to offshore areas.

A case of refractory lupus nephritis complicated by psoriasis vulgaris that was controlled with secukinumab

It has been reported that T helper 17 cells are involved in the pathogenesis of systemic lupus erythematosus, but there is no report on interleukin-17-targeted therapy. We report a case of a 62-year-old female who presented with psoriasis vulgaris and refractory lupus nephritis. Because her conditions were resistant to conventional treatment, and flow cytometry confirmed the proliferation of activated T helper 17 cells in peripheral blood, and examination of a renal biopsy tissue sample confirmed infiltration of numerous interleukin-17-positive lymphocytes to the renal interstitium, administration of the anti-interleukin-17A antibody secukinumab was initiated. After starting secukinumab the clinical and biological features were improved.

Acute Electrolyte Disturbances in Coronary Sinus during Left Coronary Arteriography in Man

Electrolyte disturbances, particularly reduction of ionized calcium, induced by iodinated contrast media (CM) are important considerations in coronary arteriography. A study was conducted in 24 patients to evaluate the acute electrolyte alterations in the coronary sinus during left coronary arteriography. During left coronary arteriography, coronary sinus blood was withdrawn for measurement of electrolytes. The CM used were diatrizoate, ioxaglate, iohexol, and iopamidol. The hematocrit was decreased moderately by all 4 CM used at 5 s and returned to the control level at 15 s. The level of ionized calcium was decreased by all CM at 5 s. Prolonged reduction of ionic calcium was observed with diatrizoate and ioxaglate at 15 s. The level of potassium was almost unchanged by diatrizoate and ioxaglate in spite of hemodilution, which may lead us to a hypothesis that potassium can be released from the intracellular spaces such as red blood cells and vascular endothelial cells. Thus the depression of left ventricular function might be caused not only by reduction of ionized calcium, but also by a relative increase in the level of serum potassium.

Age-related decline of cerebral oxygen metabolism in normal population detected with positron emission tomography

Using positron emission tomography (PET), cerebral blood flow (CBF) and cerebral metabolic rate of oxygen (CMRO2) were measured in 32 healthy volunteers aged from 27 to 67 years. In bilateral putamen, left supratemporal, left infrafrontal and left parietal cortices, CMRO2 showed a significant decline during aging. The age-related decline of CBF was seen only at the left superior temporal cortex. The mean CMRO2 was significantly lower in the elder group (over 51 years old) than in the younger group (under 50 years old), whereas no significant difference in mean CBF between the two groups. The poor correlation of CBF to the age could be explained partly by the fact that CBF is easily influenced by the physiological, psychological and/or environmental factors. The age-related changes of CMRO2 were more marked in the association cortices of the left hemisphere than in that of the right hemisphere.

Vertical and lateral transport of particulate radiocesium off Fukushima

Transport processes of particulate radiocesium were investigated using a sediment trap deployed at about 100 km east of the Fukushima Daiichi Nuclear Power Plant. A sediment trap was installed at 873 m depth of the station (119 m above the bottom), and time-series sampling of sinking particles was carried out from August, 2011 to June, 2013. The accident-derived radiocesium was detected from sinking particles over two years after the accident. Observed 137Cs flux was highest in September 2011 (98 mBq m(-2) day(-1): decay-corrected to March 11, 2011), and decreased over time with seasonal fluctuations. Particulate fluxes of radiocesium were mainly affected by two principal processes. One was the rapid sinking of radiocesium-bound particles (moderate mode). This mode was dominant especially in the early postaccident stage, and was presumed to establish the distribution of radiocesium in the offshore seabed. Another mode was observed in winter, and secondary transport of particles attributed to turbulence near the seabed increased fluxes of particulate radiocesium (turbulence mode). Although the latter process would not drastically change the distribution of sedimentary radiocesium in the short term, attention should be paid as this key process redistributing the accident-derived radiocesium may cumulatively affect the long-term distribution.

Genome-wide association study identifies a potent locus associated with human opioid sensitivity

Opioids, such as morphine and fentanyl, are widely used as effective analgesics for the treatment of acute and chronic pain. In addition, the opioid system has a key role in the rewarding effects of morphine, ethanol, cocaine and various other drugs. Although opioid sensitivity is well known to vary widely among individual subjects, several candidate genetic polymorphisms reported so far are not sufficient for fully understanding the wide range of interindividual differences in human opioid sensitivity. By conducting a multistage genome-wide association study (GWAS) in healthy subjects, we found that genetic polymorphisms within a linkage disequilibrium block that spans 2q33.3-2q34 were strongly associated with the requirements for postoperative opioid analgesics after painful cosmetic surgery. The C allele of the best candidate single-nucleotide polymorphism (SNP), rs2952768, was associated with more analgesic requirements, and consistent results were obtained in patients who underwent abdominal surgery. In addition, carriers of the C allele in this SNP exhibited less vulnerability to severe drug dependence in patients with methamphetamine dependence, alcohol dependence, and eating disorders and a lower 'Reward Dependence' score on a personality questionnaire in healthy subjects. Furthermore, the C/C genotype of this SNP was significantly associated with the elevated expression of a neighboring gene, CREB1. These results show that SNPs in this locus are the most potent genetic factors associated with human opioid sensitivity known to date, affecting both the efficacy of opioid analgesics and liability to severe substance dependence. Our findings provide valuable information for the personalized treatment of pain and drug dependence.

Development of Interferon Suppositories. I. Enhanced Rectal Absorption of Human Fibroblast Interferon by Fusogenic Lipid via Lymphotropic Delivery in Rats

We attempted to enhance the rectal absorption of human fibroblast interferon (HuIFN-β) in rats by the administration of suppositories containing fusogenic lipid and a nontoxic surfactant. Suppositories containing either the lipid (linoleic acid) or the surfactant [HCO60; polyoxyethylated (60 mol) hydrogenated castor oil] alone failed to enhance the absorption of HuIFN-β. However, suppositories containing both linoleic acid and HCO60 facilitated the rectal absorption of HuIFN-β. The absorbed HuIFN-β was selectively delivered via the lymph.

Effect of salicylate on the uptake of cefmetazole into brain of mice

Cefmetazole distribution into mice cerebral cortex was minimal when the drug was administered alone. However, the co-administration of salicylate or diethyl maleate enhanced cefmetazole uptake into the cerebral cortex, while it decreased the level of reduced nonprotein sulfhydryls in cerebral cortex. The enhanced cerebral uptake of cefmetazole was suppressed by the simultaneous administration of cysteamine with a concomitant recovery of the reduced nonprotein sulfhydryl concentration in cerebral cortex.

Potentiation of enteral absorption of human interferon alpha and selective transfer into lymphatics in rats

Enhancement of human leucocyte interferon (HuIFN-α) absorption from rat large intestine was studied with the aid of lipid, surfactant and lipid-surfactant mixed micelles. Neither the emulsified lipid (linoleic acid) nor the surfactant (HCO60, polyoxyethylated [60 moles] hydrogenated castor oil) alone were able to enhance the absorption of HuIFN-α. However, linoleic acid-HCO60 mixed micelles enhanced the absorption of HuIFN-α from the large intestine. Highly selective delivery of HuIFN-α into the lymphatics compared to the blood was also observed.

Streamline phenomena in liver metastasis of gastrointestinal tumors - a clinical-study based upon 172 patients

Location and number of liver metastasis of gastrointestinal tumors were detected preoperatively and intraoperatively. The distribution of the liver segment(s) occupied by metastatic tumors varied significantly (p<0.05). Significantly more frequent distributions were demonstrated in the lateral segment with gastric cancer (p<0.05), in the posterior segment with left colic cancer (p<0.001), in the medial segment with rectal cancer (p<0.01), in the anterior segment with bile duct cancer (p<0.05) and the whole of the liver with pancreatic cancer (p<0.05). Significantly less frequent distribution was demonstrated in the posterior segment with gastric cancer (p<0.01). When the liver was divided into the right and the left halves, the distribution of each half of the liver occupied by metastatic tumors varied significantly (p<0.05). Liver metastases of whole colic cancer were significantly more frequent in the right half of the liver (p<0.05). The results suggest that the tumor distribution in liver metastases of gastrointestinal tumors differ depending upon the primary tumors, basically in accordance with the 'streamline' phenomena.

[Thoracic surgery for patients with bronchial asthma]

Thoracic surgery poses a risk for complications in the respiratory system. In particular, for patients with bronchial asthma, we need to care for perioperative complications because it is well known that these patients frequently have respiratory complications after surgery, and they may have bronchial spasms during surgery. If we can get good control of their bronchial asthma, we can usually perform surgery for these patients without limitations. For safe postoperative care, it is desirable that these patients have stable asthma conditions that are well-controlled before surgery, as thoracic surgery requires intrabronchial intubation for anesthesia and sometimes bronchial resection. These stimulations to the bronchus do not provide for good conditions because of the risk of bronchial spasm. Therefore, we should use the same agents that are used to control bronchial asthma if it is already well controlled. If it is not, we have to administer a β₂ stimulator, aminophylline, or steroidal agents for good control. Isoflurane or sevoflurane are effective for the safe control of anesthesia during surgery, and we should use a β₂ stimulator, with or without inhalation, or steroidal agents after surgery. It is important to understand that we can perform thoracic surgery for asthma patients if we can provide perioperative control of bronchial asthma, although these patients still have severe risks.

Isolation of a thermotolerant bacterium producing medium-chain-length polyhydroxyalkanoate

AIMS

The aim of this study was to isolate a thermotolerant micro-organism that produces polyhydroxyalkanoates (PHAs) composed of medium-chain-length (mcl) HA units from a biodiesel fuel (BDF) by-product as a carbon source.

METHODS AND RESULTS

We successfully isolated a thermotolerant micro-organism, strain SG4502, capable to accumulate mcl-PHA from a BDF by-product as a carbon source at a cultivation temperature of 45°C. The strain could also produce mcl-PHA from acetate, octanoate and dodecanoate as sole carbon sources at cultivation temperatures up to 55°C. Taxonomic studies and 16S rRNA gene sequence analysis revealed that strain SG4502 was phylogenetically affiliated with species of the genus Pseudomonas. This study is the first report of PHA synthesis by a thermotolerant Pseudomonas.

CONCLUSIONS

A novel thermotolerant bacterium capable to accumulate mcl-PHA from a BDF by-product was successfully isolated.

SIGNIFICANCE AND IMPACT OF THE STUDY

A major issue regarding industrial production of microbial PHAs is their much higher production cost compared with conventional petrochemical-based plastic materials. Especially significant are the cost of a fermentative substrate and the running cost to maintain a temperature suitable for microbial growth. Thus, strain SG4502, isolated in this study, which assimilates BDF by-product and produces PHA at high temperature, would be very useful for practical application in industry.