Correction to: The search, coagulation, and clipping (SCC) method prevents delayed bleeding after gastric endoscopic submucosal dissection.

The article "The search, coagulation, and clipping (SCC) method prevents delayed bleeding after gastric endoscopic submucosal dissection", written by Motoi Azumi, Manabu Takeuchi, Youhei Koseki, Masaru Kumagai, Yoko Kobayashi, Masafumi Takatsuna, Aiko Yoshioka, Seiichi Yoshikawa, Tsutomu Miura, and Shuji Terai, was originally published electronically on the publisher's internet portal (currently SpringerLink) on 28 September 2018 without open access.

The search, coagulation, and clipping (SCC) method prevents delayed bleeding after gastric endoscopic submucosal dissection.

BACKGROUND: Delayed bleeding is an important complication after gastric endoscopic submucosal dissection (ESD). The search, coagulation, and clipping (SCC) method can be used to prevent delayed bleeding after ESD. However, its safety and efficacy are unclear. We compared the SCC method with post-ESD coagulation (PEC) to clarify the safety and efficacy of the SCC method for preventing delayed bleeding after gastric ESD. METHODS: This retrospective study included 438 patients (478 lesions) who underwent gastric ESD. Multivariate logistic regression analysis was performed to identify the significant independent factors associated with delayed bleeding and we performed propensity-score matching (PSM) to reduce the effect of procedure-selection bias of SCC method. RESULTS: Of the 438 patients, 216 underwent PEC and 222 underwent SCC. Delayed bleeding was significantly less common in the SCC than in the PEC (2.6% vs. 7.2%; P = 0.013). Among patients treated with antithrombotic therapy, the delayed bleeding rate was lower in the SCC group than in the PEC group; however, the difference was not significant (P = 0.15). The SCC method was found to be a significant independent factor for the prevention of delayed bleeding. PSM was performed in 156 patients in the PEC group and SCC group. There was a significant difference in the incidence of bleeding in the PEC and SCC groups (P = 0.013). No patient had perforation/bleeding associated with the SCC method. CONCLUSIONS: Our findings suggest that the SCC method is a simple, safe, and effective approach for preventing delayed bleeding after gastric ESD.

Plasma cells and the chronic nonsuppurative destructive cholangitis of primary biliary cirrhosis.

UNLABELLED: There has been increased interest in the role of B cells in the pathogenesis of primary biliary cirrhosis (PBC). Although the vast majority of patients with this disease have anti-mitochondrial antibodies, there is no correlation of anti-mitochondrial antibody titer and/or presence with disease severity. Furthermore, in murine models of PBC, it has been suggested that depletion of B cells may exacerbate biliary pathology. To address this issue, we focused on a detailed phenotypic characterization of mononuclear cell infiltrates surrounding the intrahepatic bile ducts of patients with PBC, primary sclerosing cholangitis, autoimmune hepatitis, chronic hepatitis C, and graft-versus-host disease, including CD3, CD4, CD8, CD20, CD38, and immunoglobulin classes, as well as double immunohistochemical staining for CD38 and IgM. Interestingly, CD20 B lymphocytes, which are a precursor of plasma cells, were found in scattered locations or occasionally forming follicle-like aggregations but were not noted at the proximal location of chronic nonsuppurative destructive cholangitis. In contrast, there was a unique and distinct coronal arrangement of CD38 cells around the intrahepatic ducts in PBC but not controls; the majority of such cells were considered plasma cells based on their expression of intracellular immunoglobulins, including IgM and IgG, but not IgA. Patients with PBC who manifest this unique coronal arrangement were those with significantly higher titers of anti-mitochondrial antibodies. CONCLUSION: These data collectively suggest a role for plasma cells in the specific destruction of intrahepatic bile ducts in PBC and confirm the increasing interest in plasma cells and autoimmunity.

Plasma isoflavone concentrations are not associated with gastric cancer risk among Japanese men and women.

The incidence of gastric cancer throughout the world is ~2-3 times higher in men than in women. Previous research suggested that isoflavones, which are structurally similar to 17ß-estradiol, may prevent gastric cancer. Based on a large, population-based, prospective study, we recently reported a null association between dietary isoflavone intake and gastric cancer. However, epidemiologic studies using blood concentrations of isoflavones might better reflect the effect of isoflavones on gastric cancer carcinogenesis than dietary assessment. We therefore conducted a nested case-control study within the Japan Public Health Center-Based Prospective Study. Participants were followed-up from 1990 to 2004. Among 36,745 participants who answered the baseline questionnaire and provided blood samples, 483 gastric cancer cases matched to 483 controls were used in the analysis. ORs and 95% CIs were estimated with a conditional logistic regression model. The overall distribution of plasma isoflavone concentrations was not associated with the development of gastric cancer. Compared with groups with the lowest plasma concentrations (reference groups), the groups with the highest daidzein and genistein concentrations had adjusted ORs and 95% CIs of 1.11 (0.74-1.66; P-trend = 0.6) and 0.96 (0.64-1.44; P-trend = 0.9), respectively. The results did not change when analysis was based on sex, subsite, or histological type. We found no association of plasma isoflavone concentrations with gastric cancer risk. Our data support the previously observed null association between isoflavone intake and gastric cancer risk.

Precise Purity Analysis of High-Purity Lanthanum Oxide by Gravimetric Analysis Assisted With Trace Elemental Analysis by Inductively Coupled Plasma Mass Spectrometry.

Gravimetric analysis was used to determine the purity of high-purity La2O3 by stepwise conversions of the weighing forms. In this study, lanthanum in the sample was converted to La oxalate, La2O3, and La2(SO4)3 to evaluate the stoichiometry of the weighing forms for accurate gravimetric determination. The losses of La in the filtrate, the washing solution of the precipitate, and the mechanical loss of La during filtration were measured using inductively coupled plasma optical emission spectrometry. The weighing forms were evaluated by comparing the observed mass ratio with the theoretical value at each conversion step. The final converted La2(SO4)3 was consistent with the theoretical composition based on the observed mass ratio of La2(SO4)3/La2O3. Additionally, impurities in the high-purity La2O3 were determined by inductively coupled plasma tandem mass spectrometry. The purity of the original La2O3 sample was precisely determined to be 99.977 % ± 0.057% (mass fraction as La2O3; the value following "±" indicates the expanded uncertainty with a coverage factor k = 2.18) by a combination of the gravimetric analysis using the precipitation from the homogeneous solution method and verification of the weighing forms for La compound.

[Palliative anti-cancer chemotherapy is safely executable in a hemodialytic patient with unresectable advanced gastric cancer].

A 75-year-old man with chronic renal failure was on maintenance hemodialysis.He was admitted to our hospital for advanced gastric cancer with multiple liver metastases (cStage IV).Three courses of tegafur-uracil (300 mg/day daily) plus docetaxel (20 mg/m², every 3 weeks) as first-line treatment and nine courses of tegafur-uracil (same dose) plus CPT-11 (64 mg/m², day 1, 15, every 4 weeks) were given without any complications.Docetaxel and CPT-11 were given on days between hemodialyses. No severe adverse effects of more than grade 3 were encountered. The standard regimens in our country for unresectable advanced gastric cancer are the S-1 single or S-1/CDDP combined chemotherapies that have already been evidenced in the JCOG 9912 and SPIRITS trial. However, no standard chemotherapy for patients on hemodialysis has been reported as yet.Therefore, doctors in charge must arrange an individualized regimen for each patient, considering metabolic characteristics of each anti-cancer agent.In this context, our case was considered to be very suggestive, and that is why we report it here in detail.

Plasma tea polyphenol levels and subsequent risk of breast cancer among Japanese women: a nested case-control study.

Although many in vitro and animal studies have suggested a protective effect of green tea against breast cancer, findings from epidemiological studies have been inconsistent. No study has used prediagnostic biomarkers of tea polyphenols, which might play a protective role. A total of 24,226 women aged 40 to 69 years in the Japan Public Health Center-based Prospective Study who responded to the baseline questionnaire and provided blood in 1990-1995 were followed to December 2002. During a mean 10.6 years of follow-up, 144 newly diagnosed breast cancers were identified. Two matched controls for each case were selected from the cohort. Plasma levels of (-)-epigallocatechin (EGC), (-)-epicatechin (EC), (-)-epigallocatechin-3-gallate (EGCG), and (-)-epicatechin-3-gallate (ECG) were measured, and the odds ratio (OR) of breast cancer according to plasma level was estimated using a conditional logistic regression model. We found no statistically significant association between plasma tea polyphenol levels and breast cancer risk. Adjusted ORs for the highest versus lowest group were 0.90 (95% CI 0.42-1.96; P for trend = 0.98) for EGC, 0.95 (95% CI 0.43-2.08; P for trend = 0.86) for EC, 1.21 (95% CI 0.52-2.80; P for trend = 0.53) for EGCG, and 1.75 (95% CI 0.81-3.78; P for trend = 0.15) for ECG. Stratified analyses according to baseline menopausal status showed no remarkable difference between two strata. This nested case-control study found no overall association between plasma tea polyphenols and the risk of breast cancer in Japan.

[An elderly hemodialytic case of recurrent esophageal cancer given combination chemotherapy with docetaxel and nedaplatin who showed temporal relief of swallowing disturbance].

An 82-year-old man was admitted for recurrent and unresectable esophageal cancer. His performance status was grade 2, although he was on hemodialysis due to chronic renal failure since 2003. Esophagogastroduodenoscopy revealed stenosis of esophagus by the recurrent tumor. After percutaneous endoscopic gastrostomy, he received biweekly combination chemotherapy with docetaxel (18 mg/m(2)) and nedaplatin (16 mg/m(2)). Hemodialysis was carried out one hour after termination of nedaplatin infusion. As severe adverse reactions due to anticancer-chemotherapy were not encountered, he could receive four courses of chemotherapy in our outpatient clinic. Difficulty in swallowing improved after the second course was finished. Finally, he died of acute myocardial infarction. In conclusion, combination chemotherapy with docetaxel and nedaplatin can be safely carried out for a patient with recurrent and unresectable esophageal cancer even on hemodialysis by appropriate down-dosing of anticancer agents.

[Retrospective analysis of generalized chemotherapy for unresectable advanced gastric cancer].

In Japan where the incidence of gastric cancer is high, the standard regimens for unresectable advanced gastric cancer are the S-1 single or S-1/CDDP combined therapies that are evidenced by the JCOG9912 and SPIRITS trial. We performed retrospective analysis on chemotherapy for unresectable advanced gastric cancer in our division from 2003 to 2008. Seventy-six patients were subjected to this study. Among them, 66 patients (86.8%) received S-1-containing regimens. Mean survival time (MST) of all patients was 309 days. MST of S-1/Paclitaxel (PTX), S-1/CPT-11 and S-1/CDDP regimens were 289, 339 and 411 days, respectively. MST of S-1/CPT-11 was significantly longer than that of S-1/PTX (p<0. 01). Next, we compared the MST among different performance statuses (PS). The respective MST of PS 0, 1, 2 cases (361, 289 and 161 days) evidenced no statistically significant difference, although the MST was shorter depending on the progression of PS. Considering the histology, the MST of patients with well- and moderately-differentiated adenocarcinoma was significantly longer than that of poorly-differentiated adenocarcinoma and signet-ring cell carcinoma (p=0. 04). The call is for more effective chemotherapy in the future based on results we will obtain from controlled studies that may also deal with the second-line chemotherapy regimens, chemotherapy for aged people and molecular-targeting cancer agents.

[A case of hepatocellular carcinoma with liver cirrhosis type C surviving over 2 years by repeated transarterial infusion therapy using cisplatinum].

A 58-year-old man with hepatocellular carcinoma (HCC) with liver cirrhosis type C was admitted to our division in April, 2004 to receive transarterial chemo-embolization (TACE) as a first-line chemotherapy for HCC. Thereafter, he had TACE twice for multicentric HCC. In December, 2005, TACE was thought to have become ineffective since his multicentric HCC progressed. So, we employed transarterial injection therapy (TAI) with fine powder cisplatinum (IAC) as a second-line chemotherapy. Stable disease was accomplished by the 22 sessions of TAI with IAC. After February 2008, IAC was given in combination with degradable starch microspheres (DSM) to reinforce the anti-cancer effect. The total therapeutic sessions using IAC became 26 in number. Total IAC amount used reached to more than 2,200 mg without any serious adverse reaction. In conclusion, TAI using IAC is thought to be effective in the chemotherapy of HCC, safely controlling the tumor progression.

[A case of interstitial pneumonia induced by gemcitabine hydrochloride for unresectable bile duct cancer].

A 78-year-old man was admitted for obstructive jaundice and unresectable bile duct cancer on March 4, 2008. Since biliary drainage was extremely difficult, he began 2 treatment courses of gemcitabine hydrochloride (GEM 800 mg/m(2) on days 1, 8, 15 every 4 weeks). He suffered from dry cough and dyspnea on May 13, 2008. He was diagnosed as GEM-induced interstitial pneumonia with severe hypoxemia by CT scan and arterial blood gas examination. He recovered with two courses of steroid pulse therapy, diuretics and antibiotics. Alternatively, he was given oral S-1 ( 80 mg/m(2) 4 weeks on and 2 weeks off) from June 12, 2008. His QOL was well kept without jaundice for as long as a half year. This is the first report of GEM-induced interstitial pneumonia in bile duct cancer. In conclusion, interstitial pneumonia must be taken into consideration as a rare adverse reaction when GEM is used for biliary neoplasms.

[A pregnant woman with inoperable advanced gastric cancer who received systemic anti-cancer chemotherapy after the non-full term fetus delivery by cesarean section].

A 28-year-old pregnant woman at 26 weeks and 2 days gestation visited a local outpatient clinic complaining of a tender abdominal mass. Examinations revealed an advanced gastric cancer with multiple liver, bone, lymph node metastasis and mesenteric dissemination, thus she was transferred to our division at 27 weeks and 1 day-gestation. With her consent we decided to maintain her pregnancy until 28 weeks when the delivered fetus could be kept alive an incubator, avoiding the adverse effect on the fetus by anti-cancer chemotherapy to mother. Rapid fetus delivery by cesarean section was carried out at 28 weeks and 1 day gestation, yielding a 958-gram baby. The mother complained of respiratory distress and suffered from lymphangitis carcinomatosa on the 3 postoperative day. We began combination chemotherapy with S-1 and paclitaxel (S-1 100 mg/day, 3 weeks on, 2 weeks off and paclitaxel 70 mg/day on 1, 8 and 15) was started on the 4th postoperative day. Although temporary regression of lymphangitis carcinomatosa was seen with a relief of symptoms, her condition deteriorated on the 24th days. The second course chemotherapy was started on the 28th days without any relief of symptoms. Her general status deteriorated and she died on the 33rd postoperative day. The association of pregnancy and gastric cancer is rare but such cases are often in an advanced clinical stage, with bad prognosis. It is necessary to determine the treatment strategy on the basis of comprehensive consideration of the status of both the mother and fetus. Upper gastrointestinal endoscopy when gastric cancer is suspected is recommended in any pregnant woman with long-term morning sickness.

Plasma levels of carotenoids, retinol and tocopherol and the risk of gastric cancer in Japan: a nested case-control study.

Fruits and vegetables have been suggested to confer protection against diseases such as cancer through the effects of antioxidants, often represented by carotenoids. We investigated the impact of carotenoids, retinol and tocopherol on gastric cancer development in a large nested case-control study among Japanese with known Helicobacter pylori infection status. A total of 36 745 subjects aged 40-69 in the Japan Public Health Center-based Prospective Study who responded to the baseline questionnaire and provided blood samples in 1990-1995 were followed until 2004. Plasma levels of carotenoids in 511 gastric cancer cases and 511 matched controls were measured by high-performance liquid chromatography. Odds ratios (ORs) and their corresponding 95% confidence intervals (CIs) were estimated using conditional logistic regression models. Plasma level of beta-carotene was inversely associated with the risk of gastric cancer (compared with the lowest quartile: OR = 0.63, 95% CI = 0.31-0.75; OR = 0.48, 95% CI = 0.31-0.75 and OR = 0.46, 95% CI = 0.28-0.75, for quartile 2, 3 and 4, respectively, P(trend) < 0.01). Inverse associations were evident in men for alpha-carotene (P(trend) = 0.04) and beta-carotene (P(trend) < 0.01), but not in women, who had relatively higher plasma levels compared with men. We found no statistically significant association between plasma levels of lutein/zeaxanthin, lycopene, retinol, alpha- or gamma-tocopherol and gastric cancer risk. Our findings suggest that those who have very low plasma levels of alpha-carotene and beta-carotene are at a higher risk of gastric cancer.

Plasma tea polyphenols and gastric cancer risk: a case-control study nested in a large population-based prospective study in Japan.

Abundant in vitro and animal studies have shown a protective effect of green tea against various types of cancer, but the evidence from epidemiologic studies is inconclusive. In this nested case-control study, we used plasma biomarkers to directly investigate the effect of tea polyphenols on the risk of gastric cancer. Subjects were followed up from 1990 to 2004. Among 36,745 subjects who answered the baseline questionnaire and provided blood samples, 494 gastric cancer cases matched to 494 controls were used in the analysis. The validated method used high-performance liquid chromatography to analyze baseline plasma samples. For men, a high plasma level of (-)-epigallocatechin was associated with an increased risk of gastric cancer. For women, a high plasma level of (-)-epicatechin-3-gallate (ECG) was associated with a decreased risk of gastric cancer; the adjusted odds ratios (95% confidence intervals) for ECG levels 0.32 to 9.2 and 9.3+ ng/mL were 1.03 (0.41-2.59) and 0.25 (0.08-0.73), respectively, compared with those whose ECG level was under the detection limit (P for trend = 0.02). Cigarette smoking was suggested to play a role as an effect modifier, which explains in part the different patterns observed by gender.

Determination of Dissolved Silica in Seawater by Ion-exclusion Chromatography with Post-column Derivatization/Silicomolybdenum Yellow Detection.

The determination of dissolved silica in seawater was investigated by an ion-exclusion chromatography with a post-column derivatization/silicomolybdenum yellow method. To determine dissolved silica in seawater accurately, the experimental conditions, such as the volume of a reaction coil, the eluent concentration and the sample dilution factor, were optimized. This is the first report that has examined the details of the experimental condition for the measurement of dissolved silica in seawater by ion-exclusion chromatography with silicomolybdenum-yellow detection. The developed method was compared with the widely used continuous flow analysis and an ion-exclusion chromatography isotope dilution inductively coupled plasma mass spectrometry, which is a primary method of measurement. The analytical results by the three methods were in good agreement, considering the expanded uncertainty with a coverage factor, 2. The validity of the three methods was confirmed with each other. The developed method can give a quantitative value with less than 1% of the expanded uncertainty, and can be used for the determination of dissolved silica in candidate reference materials having a seawater matrix.

Determination of ultra-trace sulfur in high-purity metals by isotope dilution inductively coupled plasma sector field mass spectrometry combined with chemical separation procedure.

The analytical method of ultra-trace sulfur (S) in high-purity metal by isotope dilution inductively coupled plasma mass spectrometry (ID-ICP-MS) combined with chemical separation procedure was developed in the present study. In order to determine the ultra-trace S in high-purity metal, a chemical separation with alumina column was carried out before ICP-MS measurement. This method enabled to prevent the polyatomic ion interference arising from the metal matrix and the signal suppression derived from the space charge effect in ICP-MS. In order to achieve high sensitive analysis, an ICP-sector field mass spectrometer (ICP-SFMS) was used. The isolation of polyatomic ion interference with respect to S was also carried out in medium-resolution mode. In addition, measurement conditions including detector dead time, which affects the precision and accuracy of the isotope dilution method, and washout conditions that were employed to reduce memory effects were optimized. The developed method was validated by the determination of S in a high-purity iron reference material (JSS-001-4). The analytical result obtained by the developed method (1.86 mg kg-1 ±â€¯0.12 mg kg-1 (k = 2)) was in good agreement with the certified value (1.90 mg kg-1 ±â€¯0.42 mg kg-1). The method was also applied to the determination of S in high-purity zinc, revealing a content of 0.08 mg kg-1 ±â€¯0.08 mg kg-1 (k = 2). Since the developed method enabled the determination of ultra-trace S at µg kg-1 level in the high-purity zinc, it is expected to be useful for high sensitive and accurate determination of ultra-trace S in high-purity metals.

Plasma tea catechins and risk of cardiovascular disease in middle-aged Japanese subjects: The JPHC study.

BACKGROUND AND AIMS: Although a potential benefit of drinking green tea has been suggested to reduce the development of cardiovascular disease, no study has investigated the relationship between plasma tea catechin and risk of cardiovascular disease. METHODS: A prospective, nested case-control study was conducted to examine the association between plasma tea catechin and risk of stroke and coronary heart disease (CHD) in a cohort of 29,876 men and women aged 40-69 years without history of heart disease, stroke or cancer. Participants completed a survey and donated blood samples between 1990 and 1994, and were followed-up through 2008. A total of 1132 stroke cases and 209 CHD cases, matched 1:1 to controls (n = 1132) for stroke and 1:2 to controls (n = 418) for CHD, were included in the analysis. RESULTS: We found no significant association between plasma tea catechin and the incidence of stroke or CHD in either men or women. However, we found that high plasma levels of epigallocatechin gallate (EGCG) were associated with reduced risk of stroke in non-smoking men; the adjusted odds ratio (95% CI) for the highest vs. non-detectable levels was 0.53 (0.29-0.98). The respective OR in male smokers was 1.23 (0.75-2.16). A significant interaction by smoking status was found for the highest vs. non-detected plasma EGCG in relation to stroke (p-for-interaction: p = 0.09). CONCLUSIONS: Plasma tea catechin was not associated with reduced risks of either stroke or CHD, while a protective effect of certain tea catechin on stroke risk is suggested for male non-smokers.

A Case of Successful Treatment of Ruptured Pancreaticoduodenal Artery Aneurysm Caused by Celiac Artery Dissection.

A 52-year-old man was admitted due to severe epigastric lesion pain. Esophagus gastroduodenal endoscopy showed impaired duodenal dilatation, and contrast-enhanced computed tomography revealed a pancreaticoduodenal artery (PDA) aneurysm 13 mm in diameter below the head of the pancreas, retroperitoneal hematoma, idiopathic celiac artery (CA) dissection, and common hepatic artery disruption. Angiographic embolization with a mixture of N-butyl-1,2-cyanoacrylate and lipiodol was performed, and follow-up study showed improvement of the dilatation of the duodenum and disappearance of the aneurysm. Here we report a quite rare case of PDA aneurysm by idiopathic dissection of CA treated successfully with angiographic embolization.

Determination of Ultra-trace Metal Impurities in High-purity Cadmium Using Inductively Coupled Plasma Mass Spectrometry after Matrix Separation with Anion Exchange Resin.

The analytical method for ultra-trace metal impurities at µg kg-1 level in high-purity Cd was examined by inductively coupled plasma mass spectrometry (ICP-MS) combined with matrix separation by Bio-Rad AG MP-1M anion exchange resin. After the separation of Cd, the metal impurities such as Li, In, Cr, Mn, Fe, Co, Ni, Cu, Ga, Sr, Ba and Pb were measured by an ICP-quadrupole mass spectrometer (ICP-QMS) and ICP-sector field mass spectrometer (ICP-SFMS). From the comparison of measured results, it was evaluated that the analytical sensitivity by ICP-SFMS was 10 times higher than ICP-QMS. In addition, ICP-SFMS could obtain determined values of Li and Fe that could not be determined by ICP-QMS. These results suggest the ICP-SFMS combined with matrix separation by anion exchange resin could be utilized for the determination of ultra-trace metal impurities in high-purity materials for the assessment of the purity of the materials.

Characterization of a new candidate isotopic reference material for natural Pb using primary measurement method.

A lead isotopic standard solution with natural abundance has been developed by applying a mixture of a solution of enriched 208Pb and a solution of enriched 204Pb (208Pb-204Pb double spike solution) as bracketing method. The amount-of-substance ratio of 208Pb:204Pb in this solution is accurately measured by applying EDTA titrimetry, which is one of the primary measurement methods, to each enriched Pb isotope solution. Also metal impurities affecting EDTA titration and minor lead isotopes contained in each enriched Pb isotope solution are quantified by ICP-SF-MS. The amount-of-substance ratio of 208Pb:204Pb in the 208Pb-204Pb double spike solution is 0.961959 ± 0.000056 (combined standard uncertainty; k = 1). Both the measurement of lead isotope ratios in a candidate isotopic standard solution and the correction of mass discrimination in MC-ICP-MS are carried out by coupling of a bracketing method with the 208Pb-204Pb double spike solution and a thallium internal addition method, where thallium solution is added to the standard and the sample. The measured lead isotope ratios and their expanded uncertainties (k = 2) in the candidate isotopic standard solution are 18.0900 ± 0.0046 for 206Pb:204Pb, 15.6278 ± 0.0036 for 207Pb:204Pb, 38.0626 ± 0.0089 for 208Pb:204Pb, 2.104406 ± 0.00013 for 208Pb:206Pb, and 0.863888 ± 0.000036 for 207Pb:206Pb. The expanded uncertainties are about one half of the stated uncertainty for NIST SRM 981, for 208Pb:204Pb, 207Pb:204Pb and 206Pb:204Pb, or one eighth, for 208Pb:206Pb and 207Pb:206Pb, The combined uncertainty consists of the uncertainties due to lead isotope ratio measurements and the remaining time-drift effect of mass discrimination in MC-ICP-MS, which is not removed by the coupled correction method. In the measurement of 208Pb:204Pb, 207Pb:204Pb and 206Pb:204Pb, the latter contribution is two or three times larger than the former. When the coupling of a bracketing method with the 208Pb-204Pb double spike solution and a thallium internal addition method is applied to the analysis of NIST SRM 981, the measured lead isotope ratios are in good agreement with its certified values. This proves that the developed method is not only consistent with the conventional one by NIST SRM 981 but also enables measurement of the lead isotope ratios with higher precision.