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A LA-ICP-MS based analytical method for the evaluation of trace PGE leaching.

Determination of trace elements in polymers is necessary for environmental research and compliance. The conventional solution-based inductively coupled plasma-mass spectrometry (ICP-MS) technique is time-consuming because it requires sample decomposition; thus, a faster technique such as laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) is highly desired. LA-ICP-MS allows the direct analysis of polymers, which is faster than using solution nebulization ICP-MS. In previous studies, LA-ICP-MS has been applied for the elemental analysis of polymers by calibrating with matrix-matched standard or/and internal standardization. However, the quantitative analysis of polymers containing oxygen and internal standardization using carbon have not been achieved due to the matrix effect. In this study, we report the analysis of 5 different polymers with carbon concentration ranging from 45.620 to 85.543% and containing heteroatoms such as oxygen and chlorine using a femtosecond (fs) LA-ICP-MS with internal standardization by carbon. By the optimization of laser fluence, elemental fractionation between trace elements and carbon was minimized. Trace elements (Cr, Br, Cd, Hg and Pb) in polymer reference materials including, polyethylene, polyester, acrylonitrile butadiene styrene, polyvinyl chloride, and polypropylene, were determined. The coefficients of determination (R2) of the calibration curves were improved from 0.8067–0.9880 without internal standardization to 0.9556–0.9993 with internal standardization by 13C. The determined concentrations agreed with the certified value with deviation within 30% via internal standardization by 13C. It was observed that internal standardization with 13C is effective regardless of the concentration of carbon and heteroatoms in the polymers. These results show that the polymer matrix effect was compensated. Therefore, fsLA-ICP-MS and internal standardization by 13C can be used for the determination of Cr, Br, Cd, Hg and Pb in polymers.

Background For surgery residents, opportunities to systematically learn about surgical equipment are limited. Our facility holds a simulation-based boot camp for incoming, first-year general surgery residents. The aim of this study was to assess the effectiveness of this boot camp at increasing resident confidence and improving technical skills. Methods Boot camp for incoming surgery residents is held annually and provides hands-on simulation relating to endoscopy, laparoscopy, bronchoscopy, and abdominal access. Before the boot camp, participants completed a pretest, which includes self-confidence, experience, and a skills-assessment. Identical assessments of self-confidence and skills were completed after the boot camp as a posttest. Data was accrued from 2016 to 2018. Results A total of 26, first-year, general surgery residents participated in the boot camp. Most participants had never used an endoscopic simulator (61.5%), handled a colonoscope (57.7%), a gastroscope (80.8%), or gained operative access to the abdomen (76.9%). The assessments of self-confidence and skills demonstrated a mean increase in all 4 topics. All differentials demonstrated statistical significance (P Conclusion A 1-day, simulation-based boot camp for incoming surgery residents with a focus on endoscopy, laparoscopy, and abdominal access increases resident confidence as well as several basic aspects of technical skill.

We investigated the feasibility of simultaneous detection of multiple environmentally- and biomedically-relevant RNA biomarker target sequences on a single newly fabricated 384-ch sensor array chip aiming at practical application. The individual sensor is composed of a photolithographically-fabricated Au/Cr-based electrode modified with peptide nucleic acid (PNA) probes. The sensor array chips showed sequence-specific responses upon hybridization of the probes with target sequences complementary to the probes in contrast to mismatch versions. The target oligonucleotides have 15–22 mer sequences from messenger RNAs for estrogen-responsive genes and microRNAs for lung cancer biomarkers. The dependence on target concentrations of sensor responses was observed by using a single chip on which experiments for detection of several target concentrations proceeded simultaneously, with the detection limit of 7.33 × 10−8 M. As more realistic samples, oligonucleotide samples amplified by PCR from a synthesized template sequence were applied to the chip. They showed sequence-specific responses, revealing the potential for fabricated sensor array chips to be utilized to analyze PCR samples. Unlike complicated and expensive chips that require nanofabrication, our sensor array chips based on glass coated with gold thin films are simple and can be fabricated from inexpensive and readily available materials.

Mesopancreas excision in pancreatoduodenectomy is technically complicated because of the anatomical complexity of the mesopancreas with the inferior peripancreatic blood vessels which is caused by intestinal rotation in fetal life. We have developed a novel artery-first approach (the intestinal derotation procedure) for facilitating mesopancreas excision. The aim of this study was to clarify the vascular anatomy of the mesopancreas after derotation. The right-sided colon and small intestine are mobilized from the retroperitoneum, and the intestinal loop is then derotated. In 136 cases of pancreatoduodenectomy employing the derotation procedure, we analyzed the vascular anatomy of the mesopancreas. After derotation, the anatomy was simplified. The mesopancreas extended from the right aspect of the superior mesenteric artery (SMA), forming a horizontal plane. The first jejunal trunk (FJT) was situated in parallel with the second jejunal artery and was anterior (91%) or posterior (9%) to the SMA. The inferior pancreaticoduodenal vein (IPDV) entered the right side of the FJT (83%) or the superior mesenteric vein (17%). Besides the IPDV, 1–4 tributaries entered the right wall of the FJT, in 89% of cases. The inferior pancreaticoduodenal artery was observed to originate from the right wall of the SMA, sharing a common stem with the first jejunal artery (70%) or branching directly from the SMA (29%). Intestinal derotation simplifies the mesopancreas anatomy and reveals the anatomical details of the inferior peripancreatic blood vessels in pancreatoduodenectomy.

Most patients with liver cysts are asymptomatic and require no treatment. In this patient with symptoms and restrictive ventilatory impairment, percutaneous needle aspiration with injection of minocycline hydrochloride was effective., A small number of patients with liver cysts present with symptoms. Percutaneous needle aspiration with injection of a sclerosing agent can be an effective non‐surgical treatment for patients with symptomatic cysts, and to our knowledge, this is the first case to show improvement of restrictive ventilatory impairment.

We have developed a method for the determination of Cr(VI) and Cr(III) in industrial wastewater by liquid chromatography-inductively coupled plasma mass spectrometry (LC-ICP-MS) combined with a chelating pretreatment with 2,6-pyridinedicarboxylic acid (PDCA). The PDCA unified the chemical forms of the Cr(III) species in water samples by the formation of a stable Cr(III)-PDCA complex, which was then separated by a LC column. The chromatographic mobile phase at neutral pH and the column of a mixed-bed of anion and cation exchangers successfully separated not only the chromium species without any redox conversion, but also chloride, which interfered with ICP-MS detection. The method detection limits measured at m/z 53 were 0.66 μg of Cr L-1 for Cr(III) and 0.74 μg L-1 for Cr(VI) with a sample injection volume of 20 μL under a no gas mode. The recoveries of spiked Cr(VI) at 50 and 500 g L-1 into the fifteen kinds of industrial wastewater samples were satisfactory (>90%). The proposed method for the determination of Cr(VI) was also validated by comparing with a colorimetric method using 1,5-diphenylcarbazide prescribed by the ISO 11083 and the JIS K0102.

Brine from natural salt lakes (salt brine) is an important source of lithium; consequently the recovery of lithium from brine eluates prepared through Li + adsorption-desorption is economically important. The present paper describes a study on the direct crystallization of Li 2 SO 4 ·H 2 O from synthetic and real salt-brine eluates. Thermal evaporation of a sulfate-type synthetic eluate (1400 mM Li + , 61 mM Na + , 6.7 mM K + , 16.7 mM Mg 2 + , and 10.0 mM Mn 2 + ), to a degree of concentration ( D con ) in excess of 13, produced high purity (97%) Li 2 SO 4 ·H 2 O crystals in 54% yield. The addition of ethanol to the eluate resulted in an increased yield of Li 2 SO 4 ·H 2 O crystals, but these crystals were of lower purity due to the co-precipitation of other metal sulfates. Two types of eluate were prepared by the batchwise adsorption of Li + from brine followed by desorption with 2 M sulfuric acid. Evaporation of an eluate with a Li + concentration of 1370 mM to a D con of 8.6 at 323 K produced high-purity (97%) Li 2 SO 4 ·H 2 O crystals in 43% yield after the CaSO 4 ·2H 2 O had been removed at a D con of around 3. The evaporation of the eluate to dryness at 323 K followed by rinsing with water afforded Li 2 SO 4 ·H 2 O crystals in 83% yield and in 84% purity. This simple evaporation method can be applied to lithium extraction from salt lakes in arid areas.

Desorption technology is important to fabricate the economical process for Li + recovery from brine by adsorption method, but there have been no systematic studies on the column Li + desorption. The purpose of this paper is to find the elution conditions to have the eluate with high Li + concentration in a short time, from which Li 2 CO 3 can be precipitated without pre-concentration. The promising conditions of column Li + desorption could be proposed on the bases of column desorption experiments and model calculations. The natural salt brine (pH 6.8) containing 0.21 M (1 M = 1 mol dm − 3 ) Li + , 2.7 M Na + , 0.51 M K + , 1.3 M Mg 2 + , 5.4 M Cl − , and 0.25 M SO 4 2 − was used for the Li + adsorption. The granulated adsorbent sieved to 0.42–0.71 or 0.71–1.0 mm was prepared with colloidal silica as a binder. The Li + -loaded adsorbents were prepared by treating the granulated adsorbent with the NaHCO 3 added brine by a batch method. The column elution experiments were carried out by passing HCl or H 2 SO 4 solutions with different concentrations through the Li + -loaded adsorbents at different flow rates. A model consisting of Li + migration in the solid phase and of surface H + /Li + exchange was proposed for the analysis of desorption behavior. The calculated elution curves well approximated the experimental ones when the effective acid concentration and the elution delay were considered. These approximations may be caused by the influence of the other metal ions co-adsorbed from brine. The calculation showed that the elution by passing a 2 M acid solution at a space velocity of 10/h up to 2 bed volume produces the eluate of high Li + concentration (1.15 M) with high Li + recovery (87%). This process has the advantages of eliminating the step of pre-concentration of eluate for precipitation and reducing the acid consumption.

Excision of the mesopancreas with lymphadenectomy is an important component of pancreatoduodenectomy. However, the optimal extent of lymphadenectomy remains unclear. Furthermore, accurate description of the mesopancreatic lymphatic pathways is difficult, probably because of the complex anatomy. Intestinal derotation simplifies the anatomy and facilitates both examination of lymphatic flow and the surgical procedure. The aim of this study was to evaluate lymphatic flow in the mesopancreas using indocyanine green fluorescence imaging with an intestinal derotation technique, and to clarify the optimal extent of mesopancreas excision and lymphadenectomy in pancreatoduodenectomy. Indocyanine green solution (2.5 × 10−3 mg) was injected into the pancreatic head parenchyma. After intestinal derotation, the spread of indocyanine green was observed using near-infrared imaging. Participants comprised 10 patients who underwent pancreatoduodenectomy for periampullary neoplasms. With indocyanine green fluorescence imaging, 9 of the 10 patients showed lymphatic flow from the pancreatic head to the superior mesenteric artery via the inferior pancreaticoduodenal artery and first jejunal artery (but not via the second and more distant arteries), with eventual drainage into the paraaortic region. Lymphatic pathways from the pancreatic head were connected to the superior mesenteric artery via the inferior pancreaticoduodenal artery and first jejunal artery. Excision of the mesopancreas with the inferior pancreaticoduodenal artery and first jejunal artery while preserving the second or more distant arteries appears optimal in pancreatoduodenectomy for periampullary malignancies.

We hypothesized that practicing surgeons would successfully achieve a better and more frequent Critical View of Safety (CVS) during laparoscopic cholecystectomy (LC) after participation in a structured Safe CVS Curriculum. All surgeons performing LC at a regional health system had four LC cases recorded: twice before and twice after a curriculum focused on the CVS, which was led by a member of the Society of American Gastrointestinal and Endoscopic Surgeons (SAGES) Safe LC Task Force. Videos were then de-identified and randomly ordered for grading on a 6-point CVS assessment tool by two expert surgeons, who were blinded to the operator and whether the surgeries were performed before or after the curriculum. Confidence surveys and performance on a CVS identification video quiz were also compared pre- and post-curriculum. Twelve surgeons (five general, four acute care, and three minimally invasive) with an average experience of 17.9 ± 6.3 years participated in the study. After the curriculum, surgeons achieved all three CVS criteria in more cases (1/24 (4%) versus 10/24 (42%), p

We investigated the responses of microRNAs (miRNAs) using mouse embryonic stem cells (mESCs) exposed to nine chemicals (bis(2-ethylhexyl)phthalate, p-cresol, p-dichlorobenzene, phenol, pyrocatecol, chloroform, tri-n-butyl phosphate, trichloroethylene, and benzene), which are listed as "Class I Designated Chemical Substances" from the Japan Pollutant Release and Transfer Register. Using deep sequencing analysis (RNA-seq), several miRNAs were identified that show a substantial response to general chemical toxicity (i.e., to these nine chemicals considered as a group) and several miRNA biomarkers that show a substantial and specific response to benzene. The functions of the identified miRNAs were investigated in accordance with Gene Ontology terms of their predicted target genes, indicating regulation of cellular processes. We compared the results with those for the long non-coding RNAs (ncRNAs) and mRNAs reported in our previous studies in addition to previously identified miRNAs that are either up- or down-regulated in response to the benzene as stimuli. We also observed that the changes in expression of miRNAs were smaller than those for long ncRNAs and mRNAs. Taken together the current and previous results revealed that toxic chemical stimuli regulate the expression of miRNAs. We believe that the use of miRNAs, including the thus identified miRNAs, as biomarkers contribute to predicting the potential toxicity of particular chemicals or identifying human individuals that have been exposed to chemical hazards.

We developed a novel nanocomposite bead system for detection by the naked eye of specific DNA sequences amplified by the polymerase chain reaction (PCR). The DNA probes, which were complementary to the target DNA, are conjugated with the nanocomposite beads. If the amplified products contained sequences complementary to the probes, the beads aggregated through sandwich hybridization. The aggregation was detectable as precipitation of the nanocomposite beads. The results were determined visually and did not require instrumental detection. The assay was sensitive enough to detect PCR products with a detection limit of 10 copies/tube for DNA templates. This technique is that all needed components are included within the initial cap, so that the risk of carryover contamination is very low. The nanocomposite bead system has broad application prospects for the detection of specific DNA sequences in biological and biomedical research.

OBJECTIVE A simple system is needed to determine whether surgery is indicated in cases of intraductal papillary mucinous neoplasm (IPMN). METHODS We conducted a retrospective study to identify factors predictive of malignant IPMN and thus simplify the treatment decision-making process. Ninety-six consecutive patients treated surgically for IPMN at Kyorin University Hospital (Tokyo, Japan) between 1994 and 2014 were included. Univariate and multivariate analyses were used to identify preoperative factors predictive of malignancy. A simple scoring formula was derived from the regression equation. RESULTS Twenty-two (23%) of the IPMNs were malignant, and 74 (77%) were benign. Pancreatic head tumor, cyst diameter of 47 mm or greater, and mural nodule diameter of 9 mm or greater were identified as significant predictors of malignant IPMN. The following scoring formula was developed: 4 × tumor location (pancreatic head, 1; pancreatic body or tail, 0) + 3 × cyst diameter (≥47 mm, 1

Duct-to-mucosa pancreatojejunostomy after pancreatoduodenectomy can be technically difficult, particularly in cases with a non-dilated pancreatic duct. We devised a novel procedure employing a pancreatic duct holder and mucosa squeeze-out technique facilitating duct-to-mucosa anastomosis. We compared the perioperative outcomes of pancreatoduodenectomy with duct-to-mucosa pancreatojejunostomy between the novel and conventional procedures. Our pancreatic holder has a cone-shaped tip with a slit. The holder can expand the pancreatic duct and provides a good surgical field for anastomosis. A small incision for anastomosis is made on the jejunum, while the jejunum is grasped around the incision. Then, the jejunal mucosa becomes squeezed-out and everted. This mucosa squeeze-out technique facilitates suturing the full thickness of the jejunum. Propensity score matching yielded 113 cases each undergoing the novel and the conventional procedure, among 308 cases receiving pancreatoduodenectomy with duct-to-mucosa pancreatojejunostomy. The overall morbidity rate was significantly lower in the novel procedure group. The pancreatic fistula (ISGPF grade B/C) rate was significantly lower in the novel (5 %) than in the conventional (13 %) procedure group. For cases with a non-dilated pancreatic duct (≤3 mm), the rate was significantly lower in the novel (10 %) than in the conventional procedure group (24 %). Multivariate analysis identified a non-dilated pancreatic duct, soft pancreas, and the conventional procedure as factors independently predicting the complication of pancreatic fistula formation. Our novel procedure facilitates duct-to-mucosa pancreatojejunostomy and decreases the pancreatic fistula rate. This procedure is simple, rational, and useful for achieving anastomosis, particularly in cases with a non-dilated pancreatic duct.

The availability of steelmaking slag, an industrial by-product, was examined as a component of a basal medium for the creation and regeneration of shallow habitats in coastal ecosystems. We investigated nutrient dynamics in sediments prepared with slag and dredged materials by conducting a core incubation experiment for 379 days. Silica sand was used as the reference material. Although slag caused alkalization of pore water, the pH in the surface layer recovered within a few days. The use of slag had limited influence on the dissolved inorganic nitrogen content, but pore water phosphate concentrations were considerably suppressed in slag-based media, especially when the pH was high. Nutrient diffusion fluxes from slag- and sand-based sediment cores were comparable to those in natural coastal environments. After 379 days, more than 90 % of the nutrients remained in the top 5 cm of the cores. Moreover, the sustained release of nutrients from basal media prepared with slag may play an important role in sustaining the productivity of macrophytobenthic ecosystems, including seagrass meadows. The mesocosm-scale experiment we proposed could evaluate long-term variations of nutrient dynamics in the artificial basal media. Because of wide variations in chemical properties among the different types of slag and dredged materials, approaches similar to this study may be essential before any large-scale application to marine environments.

It is not known whether autonomic neuropathy is a feature of Sjögren's syndrome (SS) or whether it is related to circulating antiganglionic acetylcholine receptor (gAChR) antibodies. The goal of the present study was to investigate the autonomic dysfunction in patients with SS and the associations between autonomic dysfunction, anti-gAChR antibodies, and clinical features of SS.(1) The first observational study tested for the presence of gAChR antibodies in the serum samples from 39 patients with SS (absent information regarding autonomic symptoms) and healthy volunteers. (2) In the second study, serological and clinical data from 10 Japanese patients diagnosed with SS were reviewed. These patients showed autonomic dysfunction, and luciferase immunoprecipitation systems (LIPS) test was conducted to detect anti-α3 and anti-β4 gAChR antibodies. (3) In the final analysis, we combined the data of seropositive SS patients with autonomic symptom from the first study with all of the patients from the second study, and analyzed the clinical features.(1) The LIPS assay revealed that anti-gAChRα3 and anti-gAChRβ4 antibodies were detected in the sera from patients with SS (23.1%, 9/39). Five of nine SS patients had autonomic symptoms. (2) Anti-α3 and anti-β4 gAChR antibodies were also detected in 80.0% (8/10) of patients with SS with autonomic symptoms. Six of the ten patients were diagnosed as having SS after neurological symptoms developed. These seropositive patients had predominant and severe autonomic symptoms and were diagnosed with autonomic neuropathy. (3) Thirteen of fifteen SS patients with autonomic symptoms (86.7%) were seropositive for anti-gAChR antibodies, and we confirmed sicca complex, orthostatic hypotension, upper and lower gastrointestinal (GI) symptoms, and bladder dysfunction at high rates.The present results suggest the possibility of anti-gAChR antibodies aiding the diagnostics of SS with autonomic dysfunction.

A model consisting of surface Li + /H + exchange followed by Li + transport with linear driving force (LDF) approximation was proposed for the analysis of column Li + adsorption from pH-buffered brine on granulated H 1.33 Mn 1.67 O 4 . The advection equations for Li + and OH − and the equations for Li + and H + transports in the solid phase were numerically solved using the finite difference technique, taking into account the acid–base properties of brine. The breakthrough curve and the pH change of the eluate could be calculated using the ion exchange capacity ( Q 0 ), ion exchange selectivity ( K c ), and Li + diffusivity in the solid phase ( D s ). The calculated breakthrough curves had good approximations to the experimental ones with the values of Q 0 = 3.0 mol/kg, K c = 0.75, and D s = 5 × 10 −9 m 2 /h; these values agreed comparatively well with those determined individually by the column and batch adsorptions with H 1.33 Mn 1.67 O 4 type adsorbent ( Q 0 = 3.4 mol/kg, K c = 0.1, and D s = 4.2 × 10 −9 m 2 /h, respectively). The rate of Li + recovery from the brine and the Li + saturation degree of adsorbent, which are important for designing the column Li + recovery process, could be evaluated from the breakthrough curves calculated at different flow rates.

Chemical safety screening requires the development of more efficient assays that do not involve testing in animals. In vitro cell-based assays are among the most appropriate alternatives to animal testing for screening of chemical toxicity. Most studies performed to date made use of mRNAs as biomarkers. Recent studies have however indicated the presence of many unannotated non-coding RNAs (ncRNAs) in the transcriptome that do appear to encode proteins. In the present study, we performed whole-transcriptome sequencing analysis (RNA-Seq) to identify novel RNA biomarkers, including ncRNAs, which showed marked responses to the toxicity of nine chemicals. Chemical safety screening was performed in cell-based assays using mouse embryonic stem cell (mESC)-derived neural cells. Marked responses in the expression of some ncRNAs to the chemical compounds were observed. The results of the present study suggested that ncRNAs may be useful in chemical safety screening as novel RNA biomarkers.

Background: Bariatric surgery for morbidly obese patients has been shown to ameliorate their quality of life (QOL). Little data are available in mildly obese patients undergoing metabolic surgery. Objectives: To investigate the impact of metabolic surgery for diabetic patients with body mass index Setting: Private practice, Japan. Methods: Fifty-one consecutive mildly obese, diabetic patients underwent laparoscopic sleeve gastrectomy with duodenojejunal bypass were initially enrolled. Only 46 returned for follow-up and were eventually included in the final population. Preoperatively, the mean weight and body mass index were 89.1 ± 11.9 kg and 31.7 ± 2.2 kg/m2, respectively. The mean fasting plasma glucose and glycated hemoglobin were 196 ± 69 mg/dL and 9.0 ± 1.5%, respectively. The mean duration of diabetes was 9.0 ± 6.1 years. Before surgery, 40 patients (78.4%) were treated with oral hypoglycemic agents and 28 patients (54.9%) were treated with subcutaneous insulin. The 36-item Short Form Survey was used to gauge HR-QOL at the preoperative phase and at 1 year after surgery. Questionnaires regarding food tolerance, food satisfaction, and dietary intake were also distributed to the enrolled patients. Results: The follow-up rate at 1 year was 90.2%. At this point, there was a decrease in mean weight and body mass index were 67.5 ± 11.6 kg and 23.9 ± 2.8 kg/m2, respectively (P Conclusions: In mildly obese patients associated with severe diabetes who underwent laparoscopic sleeve gastrectomy with duodenojejunal bypass, marked amelioration in glycemic control was observed and, although the amount of food intake and food tolerance were affected, the overall HR-QOL as well as food satisfaction improved significantly.

Long noncoding RNAs (lncRNAs) are non-protein-coding transcripts >200 nucleotides in length that have been shown to play important roles in various biological processes. The mechanisms underlying the induction of lncRNA expression by chemical exposure remain to be determined. We identified a novel class of short-lived lncRNAs with half-lives (t1/2) ≤4 hours in human HeLa Tet-off cells, which have been suggested to express many lncRNAs with regulatory functions. As they may affect various human biological processes, short-lived lncRNAs may be useful indicators of the degree of stress on chemical exposure. In the present study, we identified four short-lived lncRNAs, designated as OIP5-AS1, FLJ46906, LINC01137, and GABPB1-AS1, which showed significantly upregulated expression following exposure to hydrogen peroxide (oxidative stress), mercury II chloride (heavy metal stress), and etoposide (DNA damage stress) in human HepG2 cells. These lncRNAs may be useful indicators of chemical stress responses. The levels of these lncRNAs in the cells were increased because of chemical stress-induced prolongation of their decay. These lncRNAs were degraded by nuclear RNases, which are components of the exosome and XRN2, and chemical exposure inhibited the RNase activities within the cells.

As a result of the growing potential industrial and medical applications of multi‐walled carbon nanotubes (MWCNTs), people working in or residing near facilities that manufacture them may be exposed to airborne MWCNTs in the future. Because of concerns regarding their toxicity, quantitative data on the long‐term clearance of pristine MWCNTs from the lungs are required. We administered pristine MWCNTs well dispersed in 0.5 mg ml−1 Triton‐X solution to rats at doses of 0.20 or 0.55 mg via intratracheal instillation and investigated clearance over a 12‐month observation period. The pristine MWCNTs pulmonary burden was determined 1, 3, 7, 28, 91, 175 and 364 days after instillation using a method involving combustive oxidation and infrared analysis, combined with acid digestion and heat pretreatment. As 0.15‐ and 0.38‐mg MWCNTs were detected 1 day after administration of 0.20 and 0.55 mg MWCNTs, respectively, approximately 30% of administrated MWCNTs may have been cleared by bronchial ciliary motion within 24 h of administration. After that, the pulmonary MWCNT burden did not decrease significantly over time for up to 364 days after instillation, suggesting that MWCNTs were not readily cleared from the lung. Transmission electron microscopy (TEM) showed that alveolar macrophages internalized the MWCNTs and retained in the lung for at least 364 days after instillation. MWCNTs were not detected in the liver or brain within the 364‐day study period (, Well‐dispersed pristine MWCNTs were administered to rats at doses of 0.20 or 0.55 mg via intratracheal instillation, and investigated clearance over a 12‐month observation period. Approximately 30% of administrated MWCNTs may have been cleared by bronchial ciliary motion within 24 h of administration. After that, the pulmonary MWCNT burden did not decrease significantly over time for up to 364 days after instillation, suggesting that MWCNTs were not readily cleared from the lung. MWCNTs were not detected in the liver or brain within the 364‐day study period.

The effect of the sp(2)/sp(3) ratio in an unbalanced magnetron sputtered nanocarbon film electrode was studied for determining Cd(2+) and Pb(2+) by anodic stripping voltammetry (ASV). The signal-to-noise ratio in the ASV measurement improved as the sp(3) concentration in the carbon film increased because the noise current decreased with the increasing sp(3) concentration. The detection limits with a carbon film containing 50% sp(3) were 0.25 and 1.0 μg L(-1) for Cd(2+) and Pb(2+) with high repeatability (Cd: 4.6% and Pb: 6.4%, n = 3). For a real sample measurement, a pretreatment system combining a photooxidation reactor and a cation exchange column was used to eliminate the interference from EDTA and Cu(2+), which forms a stable complex or alloy with Cd(2+) and Pb(2+). More than 99% of the interference was eliminated, and accurate signal currents for Cd(2+) and Pb(2+) were successfully obtained with the pretreatment system.

For determination of methylmercury (MeHg) and ethylmercury (EtHg) in seawater and industrial wastewater, a simple and robust analytical method was developed based on phenylation and solvent extraction followed by GC-MS measurement. Alkylmercury compounds were directly phenylated with sodium tetraphenylborate in water and extracted into toluene. The method detection limits obtained for MeHg and EtHg in pure water were 53.3 and 33.5 ng Hg L-1, respectively, which are almost 10 times lower than the environmental quality standards for water pollution in Japan (EQSJ): 0.5 μg Hg L-1. The recoveries of alkylmercury compounds from seawater and four kinds of industrial wastewater except for EtHg from treated wastewater of an optic lens factory were satisfactory (>90%) at 1- or 4-fold concentrations of the EQSJ. Contrarily, the low recovery of EtHg from the treated wastewater (75.4 ± 4.7%) was found to be caused by the rapid decomposition of EtHg into inorganic mercury.

Objectives Reprimo gene is a cytoplasmic protein belonging to a family of molecules controlled by p53 that inhibits cell cycle progression. Ectopic expression of Reprimo results in cell cycle arrest at the G2 phase. The aim of this study was to investigate the impact of Reprimo expression on tumorigenesis of intraductal papillary mucinous neoplasm (IPMN). Methods Thirty-seven surgical cases of IPMN were collected retrospectively. Twenty-eight patients had benign IPMNs (low-grade dysplasia, n = 18; intermediate-grade dysplasia, n = 10), and the remaining 9 had malignant IPMNs (high-grade dysplasia, n = 4; invasive carcinoma, n = 5). DNA from tumor samples was extracted. DNA methylation patterns of Reprimo were determined by the methods of methylation-specific polymerase chain reaction and immunohistochemistry. The methylation status of Reprimo was compared between benign IPMNs and malignant IPMNs. Results The incidence of aberrant DNA methylation of Reprimo was significantly higher in malignant IPMNs than in benign IPMNs (78% vs 32%, P = 0.016). Furthermore, the incidence of immunohistochemical Reprimo expression was significantly lower in malignant IPMNs than in benign IPMNs (22% vs 82%, P = 0.002). Conclusions Reprimo methylation was found more frequently in malignant IPMNs. Reprimo methylation is involved in malignant transformation of IPMNs.

Inorganic arsenic (InAs) is a ubiquitous metalloid that has been shown to exert multiple adverse health outcomes. Urinary InAs and its metabolite concentration has been used as a biomarker of arsenic (As) exposure in some epidemiological studies, however, quantitative relationship between daily InAs exposure and urinary InAs metabolites concentration has not been well characterized. We collected a set of 24-h duplicated diet and spot urine sample of the next morning of diet sampling from 20 male and 19 female subjects in Japan from August 2011 to October 2012. Concentrations of As species in duplicated diet and urine samples were determined by using liquid chromatography-ICP mass spectrometry with a hydride generation system. Sum of the concentrations of urinary InAs and methylarsonic acid (MMA) was used as a measure of InAs exposure. Daily dietary InAs exposure was estimated to be 0.087 µg kg−1 day−1 (Geometric mean, GM), and GM of urinary InAs+MMA concentrations was 3.5 ng mL−1. Analysis of cova...

The aims of the present study are to clarify the changes in clinicopathologic features, diagnosis and treatment for hepatolithiasis, and propose an appropriate management strategy in Japan. The research group conducted nationwide surveys seven times in the past over a period of 40 years. Furthermore, a cohort was followed up in 2010. We analyzed the clinical features, diagnosis tools, treatment procedures, outcomes, and predictive factors for cholangiocarcinoma. Surgery was the primary method for hepatolithiasis up to 1998, and the frequency of its use has decreased since then. In 2011, 66.7% of hepatolithiasis patients were treated using nonsurgical approaches. In addition, endoscopic retrograde cholangiography (ERC) with stone extraction was the most frequently performed procedure (22.7%). However, the incidences of residual stone and recurrent stone after ERC with stone extraction were higher than those after percutaneous transhepatic cholangioscopic lithotomy and surgery. Bile duct stricture and dilatation during follow up were significant risk factors for stone recurrences. In the cohort study, stone removal only and age >65 years were significant factors for the development of cholangiocarcinoma. In patients without a history of cholangioenterostomy, left-lobe-type stones were a risk factor, and hepatectomy reduced the risk of the development of cholangiocarcinoma significantly. Nonsurgical treatment may be performed as the first-line treatment for hepatolithiasis. Surgery should be performed on patients who were treated incompletely after nonsurgical treatment. However, hepatectomy may be recommended for patients with left-lobe-type stones and without a history of cholangioenterostomy.

The concentrations of arsenic (As) species in 19 food composites prepared from 159 food items purchased in Shizuoka city, Japan, were determined (1) to estimate total daily intake of inorganic As (InAs) and some organic As species and (2) to determine food contributing to total daily InAs intake. As analysis included extraction of As species with a synthetic gastric juice (0.07 mol/L HCl + 0.01 % pepsin) from food composite and high-performance liquid chromatography-high efficiency photo-oxidation-hydride generation-inductively coupled plasma mass spectrometry. InAs was detected in 9 of 19 food composites at a concentration of 0.423-450 ng As/g fresh-weight. Daily intake of InAs from cereals was greatest (13 μg/person/day) followed by algae (5.7 μg/person/day), and the intake from the two categories constituted 90 % of the total daily InAs intake of adults (21 μg/person/day on a bioaccessible-fraction basis and 24 μg/person/day on a content basis). Analysis of individual food items showed that rice and hijiki contributed virtually 100 % of InAs from cereals and algae, respectively. The present survey indicated that InAs from rice and hijiki consumption contributed to total daily InAs intake and consequently to significant cancer risk of the general Japanese population. Daily intake of some organic forms of As and their contributing food categories was also estimated.

The reagent-free mineralization of dissolved organic matter (DOM) in river water was achieved within 1 min using a lamp-pass-through photoreactor containing a narrow reaction tube (2 mm i.d.) passing through a 40 W mercury lamp. The structure efficiently irradiated the sample solution in the tube with vacuum ultraviolet (VUV; 185 nm) light from the lamp, which rapidly decomposed the DOM with hydroxyl radicals generated efficiently from the water and oxygen that are naturally present in the solution. The photoreactor was also applicable to oxidizing reagent-free online toatal organic carbon (TOC) analysis of DOM in river-water samples using a non-dispersive infrared radiation detector after acidification of the sample using 20 mmol L(-1) phosphoric acid. The detection limit for phthalate at the injection of 390 μL was 6.2 μg of carbon L(-1). The repeatability, as expressed by the relative standard deviation, was 2.5% for thrice-repeated analyses of a river sample with 1.85 mg of carbon L(-1).

The pulmonary toxicity of multi-wall carbon nanotubes (MWCNT) were examined by intratracheal instillation. We prepared a well-dispersed MWCNT dispersion including MWCNTs of 3.71 µm geometric average length. The fiber length of most of the MWCNTs in the dispersion was 10 µm or less. The MWCNT dispersion was administered to rat lung by single intratracheal instillation at doses of 0.2 mg and 0.6 mg/rat. Bronchoalveolar lavage fluid (BALF) was collected at 3 days, 1 week, 1 month, 3 months, and 6 months after instillation. The influences of the longer MWCNTs on the induction of inflammation and oxidative stress were examined by the number of neutrophils, cytokine induced neutrophil chemoattractant-1 (CINC-1), CINC-2, CINC-3 and HO-1 in the BALF. Additionally, ho-1 gene expression in the lung was examined. The intratracheal instillation of MWCNT induced transient inflammation dose dependently in the lung. The number of neutrophils was highest at 3 days after instillation and then decreased. However, the neutrophils in the MWCNT administered animals tended to be higher than in the control group until 3 months after instillation. The CINC-1 and CINC-2 concentrations in the BALF increased at 1 month after instillation. There were no significant differences in CINC-3 and HO-1 between the MWCNT administered animals and the control animals. These results revealed that the MWCNTs of 1–10 µm in length induced persistent inflammation in rat lung. There were no remarkable differences between the MWCNTs in the present study and previously reported, shorter MWCNTs prepared from “the same” raw MWCNT material.

The pulmonary toxicity of multi-wall carbon nanotubes (MWCNT) were examined by intratracheal instillation. We prepared a well-dispersed MWCNT dispersion including MWCNTs of 3.71 µm geometric average length. The fiber length of most of the MWCNTs in the dispersion was 10 µm or less. The MWCNT dispersion was administered to rat lung by single intratracheal instillation at doses of 0.2 mg and 0.6 mg/rat. Bronchoalveolar lavage fluid (BALF) was collected at 3 days, 1 week, 1 month, 3 months, and 6 months after instillation. The influences of the longer MWCNTs on the induction of inflammation and oxidative stress were examined by the number of neutrophils, cytokine induced neutrophil chemoattractant-1 (CINC-1), CINC-2, CINC-3 and HO-1 in the BALF. Additionally, ho-1 gene expression in the lung was examined. The intratracheal instillation of MWCNT induced transient inflammation dose dependently in the lung. The number of neutrophils was highest at 3 days after instillation and then decreased. However, the neutrophils in the MWCNT administered animals tended to be higher than in the control group until 3 months after instillation. The CINC-1 and CINC-2 concentrations in the BALF increased at 1 month after instillation. There were no significant differences in CINC-3 and HO-1 between the MWCNT administered animals and the control animals. These results revealed that the MWCNTs of 1–10 µm in length induced persistent inflammation in rat lung. There were no remarkable differences between the MWCNTs in the present study and previously reported, shorter MWCNTs prepared from “the same” raw MWCNT material.

Single-Wall Carbon Nanotubes (SWCNTs) Were Well-Dispersed Using Ultrasonication to Conduct an Intratracheal Instillation Study. The Geometric Mean Diameter and Length of the SWCNT in Distilled Water Including 0.1 % Triton X-100 Was 44 Nm and 0.69 μm, Respectively. Rats Intratracheally Received 0.2 Mg or 0.4 Mg of SWCNT, and a Control Group Received Intratracheal Instillation of Distilled Water Containing 0.1 % Triton X-100 . The Rats Were then Sacrificed at 3 Days, 1 Week, 1 Month, 3 Months and 6 Months after Instillation. Bronchoalveolar Lavage Fluid (BALF) and Pathological Features Revealed that the Dose of SWCNT Induced Persistent Neutrophil Infiltration in Rat Lungs. In the Cytokine-Induced Neutrophil Chemoattractants (CINCs) Family, the Concentrations of CINC-1 and CINC-2 in the BALF Increased Persistently in the SWCNT-Exposed Groups. the Concentration of HO-1 in the BALF Was Also up-Regulated Persistently in the Exposed Groups. These Data Suggested that Well-Dispersed SWCNT Had an Inflammatory Potential in the Present Study.

Inorganic arsenic [iAs : As(III) and As(V)] concentrations in a certified reference material of total diet matrix (NIES CRM No.27 Typical Japanese Diet, TJD) were determinate by liquid chromatography-ICP mass spectrometry (LC-ICP-MS) with three different LC conditions and with or without a hydride generation system. The iAs were extracted from TJD by a method given in the literature (0.07 mol L−1 HCl + pepsin, 37°C for 2hr). The detection limits for the iAs were better than 6.1 ng As g−1 in TJD (corresponds to 0.92 ng As g−1 on a wet diet sample), indicating sufficient sensitivity for iAs in total diet samples. The reproducibility was 1.8-12.1% and the linearity of the calibration lines was satisfactory. The recovery of added iAs was 101-106%. When the extraction was repeated 3 times, the sum of the concentrations of arsenic species detected by the LC-1 agreed with the certified values for total arsenic in TJD. The total content of As(V) and As(III) was estimated to be 65 ± 2 and 18 ± 2 ng As g−1, respectively, by LC-1 condition. The analytical results of iAs in TJD based on the three LC-ICP-MS conditions by this particular extraction method were consistent with each other and the reference value was estimated to be 43 and 17 ng As g−1 for As(V) and As(III), respectively. The present results will be valuable in the quality control of iAs analysis of total diet samples for iAs risk assessment in Japan.

Fullerene (carbon sixty [C(60)]) has potential industrial and medical applications. In the future, people working in or residing near manufacturing facilities may be exposed to C(60). Therefore, quantitative data on long-term C(60) clearance from the lungs are required. To estimate the clearance rate and deposition fraction of C(60) from inhalation exposure, the C(60) burden in the lungs, liver, and brain of rats was determined after intratracheal instillation and inhalation. Male Wistar rats were intratracheally instilled with different concentrations of a C(60) suspension prepared with Tween 80 (geometric mean [GM] of particle diameter based on number, 18-29 nm; geometric standard deviation [GSD] of particle diameter, 1.5; and doses, 100, 200, and 1000 micrograms per body) or exposed to a C(60) aerosol prepared with nebulizer (GM of particle diameter based on number, 96 nm; GSD of particle diameter, 2.0; and exposure level, 120 μg/m(3)). C(60) burden in the lungs, liver, and brain was determined at various time points (1 h to 6 months) by a newly developed sensitive high-performance liquid chromatography-ultraviolet absorptiometry combined with extraction and concentration of C(60) from the organs. C(60) clearance was evaluated using a 2-compartment model: fast clearance after deposition on lung surface and slow clearance after retention in the epithelium. The detection limit of our analysis method was 8.9 ng/g tissue. Pulmonary C(60) burden decreased with time and depended on the C(60) concentration administered. The concentration of C(60) in the liver and brain was below the detection limit: 8.9 ng/g tissue. The half-life of intratracheally instilled C(60) was 15-28 days. The deposition mass fraction of inhaled C(60) was 0.14. Mode evaluation revealed that most instilled particles could be eliminated by the fast clearance pathway. This finding is consistent with the transmission electron microscopy finding that many particles were present in alveolar macrophages.

Extractions of five kinds of lanthanide metal ions by bis(2-ethylhexyl)phosphoric acid (DEHPA) with [1-Cn-3-methylimidazolium][PF 6 ](Cn = C 2 , C 4 ) or [1-butyl-4-methylpyridinium][PF 6 ] were carried out under various DEHPA and HNO 3 concentrations from 0 to 1 M and under different temperature conditions from 298 to 333 K. These results were compared with those using the conventional organic solvent, hexane, in terms of their distribution coefficient values. Under all of the conditions in this study, the ionic liquid system shows more than three times greater extractability for lanthanide compared to when hexane was used. The distribution coefficient of lanthanide ions decreased as the length of the alkyl chain increased from the ethyl to the butyl. In addition, the imidazolium cation generally shows a higher distribution coefficient compared to the pyridinium cation in an ionic liquid. The concentration ratio of lanthanides and DEHPA resulted in an extraction affinity transition for lanthanides. Also evaluated in this study were issues related to the selectivity associated with the lanthanide mixture and the dependency of the ionic radius during lanthanide extraction.

Selective photooxidation and adsorptive desulfurization of kerosene was investigated for fuel cell applications. Photooxidation was conducted using a 5 W low-pressure mercury lamp at 25 °C in the presence of O2. It was found for the first time that the rates of photooxidation of dominant sulfur compounds remaining in commercial kerosene after hydrogenation were at least 100 times higher than those of benzothiophenes (BTs) and dibenzothiophenes (DBTs), although their molecular forms were not clarified. The photooxidation of these highly reactive sulfur compounds was completed within 30 min and made them removable by adsorbents such as molecular sieves. On the other hand, non-reactive sulfur compounds such as DBTs were removed by adsorbents such as activated carbon. Using this proposed method, which combines selective photooxidation of highly reactive sulfur compounds and adsorptive desulfurization of reactive and non-reactive sulfur compounds, the total sulfur content in kerosene can be efficiently reduced to less than 0.1 μg g−1 (ppm) under mild conditions.

Concern over the influence of nanoparticles on human health has risen due to advances in the development of nanotechnology. We are interested in the influence of nanoparticles on the pulmonary system at a molecular level. In this study, gene expression profiling of the rat lung after whole-body inhalation exposure to C(60) fullerene (0.12mg/m(3); 4.1x10(4) particles/cm(3), 96nm diameter) and ultrafine nickel oxide (Uf-NiO) particles (0.2mg/m(3); 9.2x10(4) particles/cm(3), 59nm diameter) as a positive control were employed to gain insights into these molecular events. In response to C(60) fullerene exposure for 6h a day, for 4 weeks (5 days a week), C(60) fullerene particles were located in alveolar epithelial cells at 3 days post-exposure and engulfed by macrophages at both 3 days and 1 month post-exposures. Gene expression profiles revealed that few genes involved in the inflammatory response, oxidative stress, apoptosis, and metalloendopeptidase activity were up-regulated at both 3 days and 1 month post-exposure. Only some genes associated with the immune system process, including major histocompatibility complex (MHC)-mediated immunity were up-regulated. These results were significantly different from those of Uf-NiO particles which induced high expression of genes associated with chemokines, oxidative stress, and matrix metalloproteinase 12 (Mmp12), suggesting that Uf-NiO particles lead to acute inflammation for the inhalation exposure period, and the damaged tissues were repaired in the post-exposure period. We suggest that C(60) fullerene might not have a severe pulmonary toxicity under the inhalation exposure condition.

We evaluated the safety and efficacy of laparoscopic sleeve gastrectomy (LSG) for super morbid obesity in patients with an initial body mass index (BMI) of50 oror =50.Between October 2005 and January 2008, we performed LSG in 30 patients. There were 20 males and 10 females with a mean age of 38 years. Mean initial body weight and BMI were 139 kg and 49.1 kg/m(2), respectively. Sleeve gastrectomy was carried out using a linear stapler from the greater curvature of the antrum 5 cm proximal from the pyloric ring up to the angle of His alongside a 45-Fr. bougie.Laparoscopic procedures were performed successfully in all patients. The mean operation time was 92 min, and blood loss was minimal. The BMI change and weight loss at the 1-, 3-, 6-, 9-, 12-, and 18-month follow-up points of patients with an initial BMI of50 andor =50 were 34.2 and 57.4, 32.1 and 53.7, 29.6 and 50.8, 29.5 and 51.2, 27.8 and 52.2, and 29.7 and 45.5 kg/m(2) and 96.8 and 172.2, 89.5 and 157.0, 83.4 and 144.8, 84.0 and 145.4, 78.0 and 153.4, and 84.5 and 119.5 kg, respectively. The patients with a BMI of50 obtained good outcomes, but weight loss reached a plateau at 9 months after surgery in patients with a BMI ofor =50. Postoperative complications included leakage, bleeding, stricture, and peritonitis in one patient each. There was no surgical mortality. Most of the co-morbidities improved after surgery.Sleeve gastrectomy is a feasible and safe treatment for super morbid obesity, but evaluation of long-term outcome is necessary to determine whether it is a durable procedure in terms of effectiveness. We expect that patients with a BMI of50 are good candidates for LSG as a definitive treatment, and, if those with a BMI ofor =50 hope for further weight loss, a second-step procedure may be required.

The drift in sensitivity due to carbon deposition on the sampling cone, skimmer cone and ion lenses has been a serious problem in gas chromatography/inductively coupled plasma mass spectrometry (GC/ICP-MS). To overcome this problem, a high-speed switching method between a mixed-gas plasma and a pure-argon plasma (named plasma gas-switching method) using an oxygen permeation tube and a switching valve was developed. This enabled both the cleaning of deposited carbon and an enhancement of the sensitivity; as a consequence, both the repeatability and the sensitivity of polybrominated diphenylether (PBDE) were improved by more than 3 and 4 times, respectively. The drifts of sensitivity over a period of 8 h were less than 5% in most cases. Concerning the analytical performance of thermally labile congeners from octa- to deca-BDE, the detection limits, dynamic ranges of the calibration graphs and unequivalent sensitivities were remarkably improved by using a metal capillary separation column coated with a very thin (0.05 micromm) film of immobilized-polydimethylsiloxane. The detection limits ranged from 0.014 pg (BDE-154) to 0.093 pg (BDE-209), which were equal or superior to the lowest values reported hitherto by GC/MS (high resolution). A remarkable loss of sensitivity for highly-brominated congeners, such as nona- and deca-BDE, was observed in an analysis of PBDE technical mixtures when the solvent was methanol. The loss of sensitivity turned out to be due to an activation of the retention gap used for on-column injection; this problem was solved by changing methanol to isooctane in the sample-preparation step before analysis.

Seventeen trace elements in 24 coals from worldwide deposits of differing ranks and sulfur contents were determined with the use of inductively coupled plasma optical emission spectrometry (ICP-OES), inductively coupled plasma mass spectrometry (ICP-MS), and flow injection (FI) ICP-MS. By examining multiple correlations between each trace element and three major elements, calcium, aluminum, and iron, we have found that thirteen trace elements (Li, Be, V, Cr, Mn, Ni, Cu, Zn, Ga, As, Se, Sr, and Ba) in the coals show significant correspondence. Elements correlating with aluminum are lithium, beryllium, vanadium, chromium, copper, gallium, and selenium; of these elements, vanadium, chromium, and copper also have a relationship with iron. Manganese, strontium and barium are correlated with calcium, while nickel, zinc, and arsenic are correlated with iron. In the geochemical and mineralogical senses, the significant correlation of a trace element with calcium reflects its common association with carbonate minerals for medium- to high-rank coals, while that with aluminum is implicative of the common association with aluminosilicate minerals and that with iron is characteristic of the association with sulfide minerals for high-sulfur coals, and with iron-bearing carbonate and clay minerals for low-sulfur coals. It is observed that most trace elements have more than one common association(s) in the 24 coals.

Two Argonne premium coal samples, Illinois No. 6 (IL) and Wyodak-Anderson (WY), were extracted by 1-methynaphthalene for 1 h at 360{sup o}C and under 1 MPa nitrogen (cold) protection. Elution of inorganic elements into coal extracts as well as their chemistry has been mainly investigated. An indirect method for metallic speciation was employed by initially washing coal with a variety of acids. Subsequently, the washed coals as well as the respective raw coal were extracted. For a given metal, elution of its ion-exchangeable fraction was defined as the difference between its amounts eluted into the extracts of raw coal and acetic acid-washed coal. Elution of submicrometer discrete particles was defined as the difference between the extracts of acetic acid-washed coal and nitric acid-washed coal. Elution of its fraction insoluble in nitric acid was assigned as organometals which are chemically associated with coal carbonaceous matrix and/or those incorporated into fine clay minerals. About 822 and 1110 ppm inorganic elements were eluted into the extracts of IL and WY coals, respectively. Fe was the most prevalent. The transition metals including Cr, Ni, Mn, Co, Cu, and Zn were also abundant. These metals were mostly nitric-acid insoluble. Electron spin resonance spectroscopy characterization suggestedmore » the high-spin Fe{sup 3+} state for Fe that is virtually totally associated with coal functional groups. Regarding the remaining metals in coal extracts, they are mainly submicrometer discrete particles in IL extract. Elution of the ion-exchangeable carboxylates was however prominent during WY coal extraction. 43 refs., 6 figs., 5 tabs.« less

In this paper, the partitioning behavior of boron has been investigated in one coal extraction process, named HyperCoal (HPC) generation, developed in Japan. Five coals were extracted by both 1-methynaphthalene and its mixture with 20 wt % polar indole for 1 h at 360{sup o}C. Boron in coal extract (HPC), coal residues, and raw coals has been examined by inductively coupled plasma-optical emission spectroscopy and solid-state {sup 11}B magic angle spinning-nuclear magnetic resonance spectroscopy. The results indicate that, regardless of the coal rank, boron has a lower concentration in HPC than in the corresponding raw coal and coal residue. Up to 20% of the original boron could be eluted. The eluted boron is an organoboron complex associated chemically within the coal matrix which has the following characteristics: resonates from -5.88 to -7.00 ppm in {sup 11}B NMR spectra, completely decomposes when coal is ashed by plasma at 150-200 {sup o}C, and is insoluble in acetic acid while preferentially extracted by organic solvents. No boron-bearing mineral particles have been detected in HPCs. Regarding the elution amount of boron, it is a function of the fraction of organoboron in raw coal and HPC yield. For raw coal having more organoboron as wellmore » as a higher HPC yield, a larger fraction of its original boron could be extracted accordingly. The eluted boron could also in part undergo chemical reactions with coal radicals and/or polar indole to form new coordination states in HPCs. 37 refs., 9 figs., 5 tabs.« less

ガスクロマトグラフィー/誘導結合プラズマ質量分析法（GC/ICP-MS）による石油中硫黄化合物の高感度な検出法を開発し，定量への可能性を示した．ICP-MSのバックグラウンド強度に占める酸素分子イオン及び硫黄のコンタミネーションの寄与を明らかにし，酸素分子イオンの干渉はICP出力を高めることにより，また，硫黄のコンタミネーションはインターフェイス材質の選択や，Arガスの精製により大幅に低減した．化学形態別感度及びマトリックス干渉のICP出力依存性を調べ，高出力ほど高感度であり，マトリックス干渉が小さいことを明らかにした．検出限界は約0.6 ng S mL−1，GC注入量（1 μL）とスプリット比を考慮すると，ICP-MSで検出される絶対量としては約0.05 pgとなり，炎光光度法（FPD）やマイクロ波誘導プラズマ発光検出器（MIP-AED）に対して2～3けた，pulsed FPDや化学発光硫黄検出器（SCD）に対しても同等ないしは1けたほど優れていた．本法は化学形態によらず等しい感度が期待されるが，実際にはGCのスプリット注入に伴うディスクリミネーションやGCカラムでの分解のため，高沸点化合物の感度が低くなった．実試料としてナフサ，ガソリン，灯油，軽油に本法を適用した結果，他の検出方法（AED，SCD）より低濃度成分まで検出できることを確認した．一方，炭化水素によるクエンチングがSCDに比べて大きく，この抑制が今後の課題であることが明らかとなった．