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The lithology and genesis of a dark grey clastic interlayer first encountered within the deepest potassium-rich salt body in the Simao Basin, southwestern China, were analysed. Analyses of the petrography, mineralogy, and element geochemistry of the layer revealed that (1) the layer contains quartz crystals with gulf corrosion edges and explosion cracks and angular volcanic ash-sized glasses; (2) the main mineral components of the crystal fragments are chlorite, illite, biotite, quartz, anhydrite, gypsum, magnesite, pyrite, molybdenite, clinopyroxene, and zircon; (3) the rare earth element patterns, Zr/TiO2 and Nb/Y diagrams as well as boron content all indicate a volcanic origin for the layer. Based on these observations, the layer is suggested to be an altered tuff associated with various volcanic fragments dominated by chlorite and formed after alteration of a parent tuff in an alkaline, salty, and low-temperature water body. Discovery of the layer indicates that the potash-bearing salt rocks could have taken in volcanic materials during these volcanic activities and provides the possibility of reliable zircon U‒Pb dating to determine the absolute age of the host rock, which is fundamental in studying the genetic mechanism of this deeply buried salt body. [ABSTRACT FROM AUTHOR]

Background: Real‐world safety and effectiveness data for trastuzumab plus chemotherapy treatment of patients with HER2‐positive metastatic gastric cancer (mGC) in China are lacking. Patients and Methods: EVIDENCE was a prospective, multicenter, noninterventional registry study evaluating the safety and effectiveness of trastuzumab in five cohorts of Chinese patients with gastric cancer, stratified by HER2 status and trastuzumab treatment. Effectiveness was analyzed for cohorts I (HER2‐positive, trastuzumab treated), II (HER2‐positive, trastuzumab untreated), and IV (HER2‐negative, trastuzumab untreated); trastuzumab‐related adverse events (AEs) were analyzed for cohort I. Results: Cohorts I, II, and IV included 174, 113, and 422 patients, respectively. Most patients received first‐line chemotherapy (87.6%). Median overall survival (OS1) for first‐line treatment was 22.3, 17.2, and 17.4 months in cohorts I, II, and IV, respectively. After excluding patients who had surgery, respective median OS1 was 19.9, 15.3, and 12.9 months. Respective first‐line progression‐free survival (PFS1) was 8.2, 6.9, and 6.2 months; and respective first‐line response rates (RR) were 51.7%, 18.4%, and 32.8%. Cohort I was significantly favored over cohort II for propensity score–matched first‐line median OS1 (hazard ratio [HR], 0.61), PFS1 (HR, 0.64), and RR (odds ratio, 4.93). Trastuzumab‐related AEs, grade 3–5 AEs, serious AEs, and AEs with a fatal outcome occurred in 23.6%, 3.4%, 2.3%, and 0.6% of cohort I patients, respectively. Conclusion: Safety profiles were consistent with those known for trastuzumab and chemotherapy; trastuzumab treatment improved outcomes. Our study provides real‐world data supporting first‐line trastuzumab plus chemotherapy in Chinese patients with HER2‐positive mGC. Implications for Practice: This prospective, noninterventional registry study aimed to provide safety and effectiveness data for the use of trastuzumab in combination with chemotherapy in Chinese patients with HER2‐positive metastatic gastric cancer (mGC) from the real‐world clinical setting. Trastuzumab plus first‐line chemotherapy was shown to be safe and to improve outcomes when compared with patients treated with chemotherapy alone. Trastuzumab was effective within a range of treatment regimens; subgroup analysis showed that trastuzumab paired most effectively with the XELOX regimen. This study provides real‐world clinical safety and effectiveness data supporting the use of trastuzumab in the treatment of Chinese patients with HER2‐positive mGC. This article reports the results of the EVIDENCE study, which evaluated the effectiveness and safety of trastuzumab in patients with HER2‐positive metastatic gastric cancer in a real‐world setting in China. [ABSTRACT FROM AUTHOR]

Objective: Lactulose is effective in the treatment and prevention of overt hepatic encephalopathy (OHE), but there are limited data on its use on microbiota in relations to minimal hepatic encephalopathy (MHE) recovery. The present study aimed to assess the efficacy of lactulose in recovery of MHE in aspects of cognitive function, quality of life, and impact on intestinal microbiota. Methods: This multicenter, open‐label randomized controlled trial was conducted in 11 teaching hospitals in China. Participants were randomly allocated on a 2:1 basis to receive lactulose (Gp‐L) or no therapy as control (Gp‐NL) for 60 days. The primary endpoint was the MHE reversal rate. Gut microbiota were compared between MHE patients and healthy volunteers, as well as lactulose‐responders and non‐responders. Results: A total of 98 cirrhotic patients were included in the study, with 31 patients in the Gp‐NL group and 67 patients in the Gp‐L group. At day 60, the MHE reversal rate in Gp‐L (64.18%) was significantly higher than that in Gp‐NL (22.58%) (P =.0002) with a relative risk of 0.46 (95% confidence interval 0.32‐0.67). Number needed to treat was 2.4. Further, there was significantly more improvement in physical functioning in Gp‐L (4.62 ± 6.16) than in Gp‐NL (1.50 ± 5.34) (P =.0212). Proteobacteria was significantly higher in MHE patients compared with healthy volunteers (12.27% vs 4.65%, P < .05). Significant differences were found between lactulose responders and non‐responders in Actinobacteria, Bacteroidetes, Firmicutes, and Proteobacteria. Conclusions: Treatment with lactulose significantly improves MHE recovery rate, and gut microbiota change in MHE patients can modulate the effectiveness of this therapy. Chinese Clinical Trial Register (ChiCTR) (ID: ChiCTR‐TRC‐12002342). [ABSTRACT FROM AUTHOR]

No prediction rule is currently available for advanced colorectal neoplasms, defined as invasive cancer, an adenoma of 10 mm or more, a villous adenoma, or an adenoma with high-grade dysplasia, in average-risk Chinese. In this study between 2006 and 2008, a total of 7,541 average-risk Chinese persons aged 40 years or older who had complete colonoscopy were included. The derivation and validation cohorts consisted of 5,229 and 2,312 persons, respectively. A prediction rule was developed from a logistic regression model and then internally and externally validated. The prediction rule comprised 8 variables (age, sex, smoking, diabetes mellitus, green vegetables, pickled food, fried food, and white meat), with scores ranging from 0 to 14. Among the participants with low-risk (≤3) or high-risk (>3) scores in the validation cohort, the risks of advanced neoplasms were 2.6% and 10.0% (P < 0.001), respectively. If colonoscopy was used only for persons with high risk, 80.3% of persons with advanced neoplasms would be detected while the number of colonoscopies would be reduced by 49.2%. The prediction rule had good discrimination (area under the receiver operating characteristic curve = 0.74, 95% confidence interval: 0.70, 0.78) and calibration (P = 0.77) and, thus, provides accurate risk stratification for advanced neoplasms in average-risk Chinese. [ABSTRACT FROM PUBLISHER]

Objective: Helicobacter pylori infection is mostly a family-based infectious disease. To facilitate its prevention and management, a national consensus meeting was held to review current evidence and propose strategies for population-wide and family-based H. pylori infection control and management to reduce the related disease burden., Methods: Fifty-seven experts from 41 major universities and institutions in 20 provinces/regions of mainland China were invited to review evidence and modify statements using Delphi process and grading of recommendations assessment, development and evaluation system. The consensus level was defined as ≥80% for agreement on the proposed statements., Results: Experts discussed and modified the original 23 statements on family-based H. pylori infection transmission, control and management, and reached consensus on 16 statements. The final report consists of three parts: (1) H. pylori infection and transmission among family members, (2) prevention and management of H. pylori infection in children and elderly people within households, and (3) strategies for prevention and management of H. pylori infection for family members. In addition to the 'test-and-treat' and 'screen-and-treat' strategies, this consensus also introduced a novel third 'family-based H. pylori infection control and management' strategy to prevent its intrafamilial transmission and development of related diseases., Conclusion: H. pylori is transmissible from person to person, and among family members. A family-based H. pylori prevention and eradication strategy would be a suitable approach to prevent its intra-familial transmission and related diseases. The notion and practice would be beneficial not only for Chinese residents but also valuable as a reference for other highly infected areas., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2022. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Background: Molecular features underlining the multistage progression of gastric lesions and development of early gastric cancer (GC) are poorly understood, restricting the ability to GC prevention and management., Methods: We portrayed proteomic landscape and explored proteomic signatures associated with progression of gastric lesions and risk of early GC. Tissue proteomic profiling was conducted for a total of 324 subjects. A case-control study was performed in the discovery stage (n=169) based on populations from Linqu, a known high-risk area for GC in China. We then conducted two-stage validation, including a cohort study from Linqu (n = 56), with prospective follow-up for progression of gastric lesions (280-473 days), and an independent case-control study from Beijing (n = 99)., Findings: There was a clear distinction in proteomic features for precancerous gastric lesions and GC. We derived four molecular subtypes of gastric lesions and identified subtype-S4 with the highest progression risk. We found 104 positively-associated and 113 inversely-associated proteins for early GC, with APOA1BP, PGC, HPX and DDT associated with the risk of gastric lesion progression. Integrating these proteomic signatures, the ability to predict progression of gastric lesions was significantly strengthened (areas-under-the-curve=0.88 (95%CI: 0.78-0.99) vs. 0.56 (0.36-0.76), Delong's P = 0.002). Immunohistochemistry assays and examination at mRNA level validated the findings for four proteins., Interpretation: We defined proteomic signatures for progression of gastric lesions and risk of early GC, which may have translational significance for identifying particularly high-risk population and detecting GC at an early stage, improving potential for targeted GC prevention., Funding: The funders are listed in the Acknowledgement., Competing Interests: Declaration of Competing Interest XL, NRZ, YW and JQ have a pending patent entitled “Proteomic subtyping of precancerous gastric lesions, biomarkers associated with gastric cancer and gastric lesion progression and prediction models for gastric lesion progression” (CNIPA patent application number: 202010958039X, filed September 11, 2020). The other authors have declared that no conflict of interest exists., (Copyright © 2021 The Authors. Published by Elsevier B.V. All rights reserved.)

Background: Poorly differentiated gastric neuroendocrine neoplasms (PDGNENs) include gastric neuroendocrine carcinoma (NEC) and mixed adenoneuroendocrine carcinoma, which are highly malignant and rare tumors, and their incidence has increased over the past few decades. However, the clinicopathological features and outcomes of patients with PDGNENs have not been completely elucidated., Aim: To investigate the clinicopathological characteristics and prognostic factors of patients with PDGNENs ., Methods: The data from seven centers in China from March 2007 to November 2019 were analyzed retrospectively., Results: Among the 232 patients with PDGNENs, 191 (82.3%) were male, with an average age of 62.83 ± 9.11 years. One hundred and thirteen (49.34%) of 229 patients had a stage III disease and 86 (37.55%) had stage IV disease. Three (1.58%) of 190 patients had no clinical symptoms, while 187 (98.42%) patients presented clinical symptoms. The tumors were mainly (89.17%) solitary and located in the upper third of the stomach (cardia and fundus of stomach: 115/215, 53.49%). Most lesions were ulcers (157/232, 67.67%), with an average diameter of 4.66 ± 2.77 cm. In terms of tumor invasion, the majority of tumors invaded the serosa (116/198, 58.58%). The median survival time of the 232 patients was 13.50 mo (7, 31 mo), and the overall 1-year, 3-year, and 5-year survival rates were 49%, 19%, and 5%, respectively. According to univariate analysis, tumor number, tumor diameter, gastric invasion status, American Joint Committee on Cancer (AJCC) stage, and distant metastasis status were prognostic factors for patients with PDGNENs. Multivariate analysis showed that tumor number, tumor diameter, AJCC stage, and distant metastasis status were independent prognostic factors for patients with PDGNENs., Conclusion: The overall prognosis of patients with PDGNENs is poor. The outcomes of patients with a tumor diameter > 5 cm, multiple tumors, and stage IV tumors are worse than those of other patients., Competing Interests: Conflict-of-interest statement: The authors have no competing interests to declare., (©The Author(s) 2021. Published by Baishideng Publishing Group Inc. All rights reserved.)

Aim: To explore the association of MYO9B gene polymorphisms with clinical phenotypes and intestinal permeability of individuals with inflammatory bowel disease (IBD) in China., Methods: A total of 442 IBD patients and 402 healthy volunteers were genotyped for two single nucleotides (rs962917 and rs1545620) using the ligase detection reaction and polymerase chain reaction. Allelic and genotype frequency analyses were performed for the two groups. Intestinal permeability was evaluated using lactulose (L) and mannitol (M) excretion. The association of MYO9B gene polymorphisms with intestinal permeability between the normal and high intestinal permeability groups was analyzed., Results: Overall, there was no significant difference in the genotypic and allelic frequencies of MYO9B between IBD patients and controls. Although no association was found with ulcerative colitis in the comparison between the subgroups, the frequencies of rs962917 and rs1545620 were different in the Crohn's disease (CD) subgroup with ileocolitis (CC vs CT and TT, P = 0.014; and AA vs AC and CC, P = 0.022, respectively). rs1545620 variants appear to be the genetic susceptibility factor for perianal disease in CD patients (AA vs AC CC, P = 0.029). In addition, the L/M ratio was significantly higher in IBD patients than in controls (0.065 ± 0.013 vs 0.020 ± 0.002, P = 0.02), but no association was found between the MYO9B gene and the L/M ratio in IBD patients., Conclusion: MYO9B gene polymorphisms may influence the sub-phenotypic expression of CD in China. No association between these MYO9B polymorphisms and intestinal permeability in IBD patients was found.

Aim: To construct normal values for the tests of the psychometric hepatic encephalopathy score (PHES) and to evaluate its usefulness in the diagnosis of minimal hepatic encephalopathy (MHE) among Chinese individuals with cirrhosis., Methods: The five tests of PHES, number connection test-A (NCT-A), number connection test-B, serial dotting test, line tracing test and digit symbol test (DST), were administered to all enrolled subjects in a quiet room with sufficient light. Cirrhotic subjects with overt HE were excluded by the West-Haven criteria and a detailed neurological examination. Based on the nomograms of healthy volunteers, the patients were classified as having MHE when their PHES was less than -4., Results: In total, 146 healthy volunteers completed all the PHES tests. Age and education years were confirmed to be predictors of all five tests. In total, 53 patients with liver cirrhosis completed the PHES. Of the patients with liver cirrhosis, 24 (45.3%), 22(41.5%) and 7(13.2%) had Child-Pugh grades A, B and C, respectively. MHE was diagnosed in 26 patients (49.1%). Compared with compensated cirrhotic patients (Child A), decompensated cirrhotic patients (Child B and C) had a higher proportion of MHE (65.5% vs 29.2%). No differences in age and education years were found between the MHE and non-MHE groups. NCT-A and DST were able to diagnose MHE with a sensitivity of 76.9% and a specificity of 96.3% (AUC = 0.866, K = 0.735)., Conclusion: The proportion of MHE is associated with liver function. NCT-A and DST are simple tools that can be used for the diagnosis of MHE in China.

Aim: To investigate the prevalence of minimal hepatic encephalopathy (MHE) and to assess corresponding health-related quality of life (HRQoL) in hospitalized cirrhotic patients in China., Methods: This multi-center cross-sectional study included 16 teaching hospitals, which were members of "Hepatobiliary Cooperation Group, Society of Gastroenterology, Chinese Medical Association", from different areas of China carried out between June and October in 2011. All the eligible hospitalized cirrhotic patients (n = 538) were required to complete triplicate number connection tests combined with one digit symbol test for diagnosing MHE. Patients' clinical examination data were complemented by a modified questionnaire assessing HRQoL. Written informed consent was obtained from each patient., Results: Male was predominant (68.6%) in 519 patients who met the criteria of the study, with a mean age of 49.17 ± 11.02 years. The most common cause of liver cirrhosis was chronic hepatitis B (55.9%). The prevalence of MHE was 39.9% and varied by Child-Pugh-Classification score (CPC-A: 24.8%, CPC-B: 39.4% and CPC-C: 56.1%, P < 0.01). MHE (P < 0.01) and higher CPC scores (P < 0.01) were associated with a high HRQoL scores (reflecting poorer quality of life). The prevalence of MHE was proportionate to CPC (P = 0.01) and high quality of life scores (P = 0.01)., Conclusion: Hospitalized cirrhotic patients have a high prevalence of MHE that is proportionate to the degree of liver function and HRQoL impairment.

Objective: To evaluate the efficacy and safety of trastuzumab in combination with chemotherapy versus chemotherapy alone in the first-line treatment of HER-2-positive advanced gastric or gastro-oesophageal junction cancer., Methods: Fifteen Chinese research centers are involved in the BO18255 (ToGA) study. Patients with gastric or gastro-oesophageal junction cancer were eligible for inclusion if their tumor showed overexpression of HER-2 protein by immunohistochemistry +++ or FISH-positive. Patients were randomly assigned in a 1:1 ratio to receive a chemotherapy regimen consisting of capecitabine or 5-FU plus cisplatin or chemotherapy in combination with intravenous trastuzumab. The primary endpoint was overall survival., Results: Eighty-five Chinese patients were enrolled in this study, of whom 84 were included in the primary analysis: trastuzumab plus chemotherapy (FP/H) (n = 36) and chemotherapy alone (FP)(n = 48). The median follow-up was 15.2 months in the FP/H group and 14.2 months in the FP group. The median survival time was 12.6 months in the FP/H group compared with 9.7 months in the FP group [hazard ratio 0.72, 95%CI (0.40; 1.29)]. Grade 3/4 adverse events were higher in the FP/H(63.9%)than FP (47.9%) groups, including neutropenia, vomiting and nausea. Two mild cardiac adverse events occurred in the FP/H group. Severe adverse events occurred in 3 cases of both two groups, respectively., Conclusions: Addition of trastuzumab to chemotherapy is well tolerated and shows improved survival in Chinese patients with advanced gastric or gastro-oesophageal junction cancer. These results are consistent with the results of ToGA whole population trial. Trastuzumab in combination with chemotherapy can be considered as a new option for patients with HER-2-positive advanced gastric or gastro-oesophageal junction cancer.

Objective: To explore the effects of 7-day quadruple regimen as the first-line therapy strategy for Helicobacter pylori(H. pylori)infection and compare the eradication rate of ilaprazole versus esoprazole-based regimen., Methods: A total of 440 patients with H. pylori infection, who had never received H. pylori eradication treatment, were enrolled from 10 domestic hospitals from October 2010 to July 2011. Diagnosed as chronic gastritis or duodenal ulcer according to their endoscopic examination results, they were randomized into ilaprazole and(or) esoprazole-based bismuth-containing quadruple regimen group with amoxicillin and clarithromycin (n = 110 each). After a 7-day eradication treatment, all patients with duodenal ulcer received PPI (ilaprazole and(or) esoprazole) treatment for 14 days and (13)C urea breath test was performed at least 28 days after the end of therapy. The patients with failed eradication treatment underwent endoscopy examination and biopsy. H. pylori culture and detection of antibiotic-resistant genes were also performed., Results: In gastritis patients, the eradication rate (per-protocol, PP value) were 78.2% (79/101) and 82.0% (82/100) in ilaprazole and esoprazole groups (P = 0.50) while the (intention-to-treat) ITT value of eradication rate were 71.8% (79/110) and 74.5% (82/110) in ilaprazole and esoprazole groups respectively (P = 0.65). And there was no statistical difference (P > 0.05). In duodenal patients, the eradication rate (PP) were 92.1% (93/101) and 91.4% (96/105) in ilaprazole and esoprazole group (P = 0.86) while the ITT value of eradication rate were 84.5% (93/110) and 87.3% (96/110) in ilaprazole and esoprazole groups respectively (P = 0.56). And no significant difference existed between two groups in gastritis and duodenal ulcer patients (P > 0.05). In total, the eradication rate was 80.1% (161/201) (PP) and 73.2% (161/220) (ITT), 91.7% (189/206) (PP) and 85.9% (189/220) (ITT) in chronic gastritis and duodenal ulcer patients respectively. The symptomatic improvements of stomachache, burning, belching and nausea remained almost unchanged. No severe side effect was observed. The point mutations for clarithromycin resistance were detected in all 53 H. pylori strains (100%) isolated from the patients with failed eradication treatment., Conclusions: The eradication rate of PPI based bismuth-containing quadruple regimen as the first-line treatment is satisfactory in chronic gastritis and duodenal ulcer patients. No significant difference exists between the effects of ilaprazole and esoprazole-based groups. And the treatment failure may be attributed mainly to the clarithromycin resistance of H. pylori.

Suspended sediment is one of the major optically active substances in coastal waters. The knowledge of its spectral characteristics is the basis for developing precise remote sensing inversion algorithms. Two separate continuous monitoring stations were set near the northern and southern coast of Hangzhou Bay separately, which is typically turbid area in China coastal waters. The above-water measurement method and the American ASD portable spectroscope were adopted to measure the water surface reflectance spectrum. The sediment concentrations of surface water were synchronously acquired when measuring water-leaving radiance. Results show that the sediments concentration is comparatively high and changes dramatically according to tide cycle. The reflectance spectrum at different wavelengths rises corresponding to the increase in sediments concentrations with different extent. When using first derivative method to analysis the spectral characteristic, it can be found that the first reflectance peaks of reflectance spectra appear to shift to long wavelength. There are different correlations between sediment concentrations and each MODIS channel reflectance, which are above 0.5 in 650 nm or longer wavelengths channels and below 0.5 in 400-550 nm channels. The fitting result of regression analysis is preferable with MODIS channel 2 (841-876 nm) and in situ sediment concentrations using least square method, with R2 of exponential above 0.8, which indicated that the MODIS channel 2 can be used for surface water suspended sediments remote sensing inversion, particularly in turbid waters such as bays and estuaries.

Suspended particles are one of major parameters of coastal water color remote sensing in China. The reflectances spectral of water were measured using an ASD field spectroscope, synchronously the suspended particles concentrations of surface water were acquired in Hangzhou Bay. Two remote sensing inversion models for suspended particles concentrations (SPC) were developed based on t hesimulated reflectance of MODIS & MERIS channels using artificial neural network (ANN) algorithm. Measurement results show that the total SPC of Hangzhou bay is comparatively high where the suspended sediments concentrations (SSC) are far more than chlorophyll concentrations, averagely 705 mg/L and 1.164 mg/m3, reseparately. The SPC in two measurement stations appears spatio-temporal variation, especially the short period change due to tidal cycle. There are two reflectance peaks in the measured spectral curves, one is between 650 nm to 750 nm, and the other is near 800 nm. The first order derivative curves of reflectance spectral indicate that the first reflectance peaks shift to long wavelength according to the increased SSC. The ANN models make full use of the spectral information in different channels which can simulate the pigment and non-pigment particles concentrations at same time. The fitting effects are preferable with R2 more than 0.95 for each model. The ANN mode can be used for satellite remote sensing inversion, especially MERIS data, because of its comparatively high spatial resolution.

Objective: To assess the polymorphism of UGT1A gene in Chinese, and to investigate the correlation between UGT1A polymorphism and irinotecan toxicity in colorectal cancer patients., Methods: 70 patients with advanced colorectal cancer were treated with irinotecan and 5-fluorouracil. Polymorphism analysis was performed in all those patients and 100 healthy subjects. Genomic DNA was extracted from peripheral blood and genotyped using polymerase chain reaction and direct sequencing., Results: 14 patients exhibiting grade 3 - 4 neutropenia (20.0%), 16 patients experienced grade 2 - 4 diarrhea (22.9%), including only 4 patients with grade 3 - 4 diarrhea (5.7%). Compared with TA6/7 and TA7/7, UGT1 A1 * 28 wild genotype TA6/6 was significantly associated with reduced toxicity (42.1% vs. 15.7%, P = 0.027). There was no significant difference in the distribution of UGT1A genotypes between colorectal cancer patients and healthy subjects., Conclusion: Chinese patients exhibit less irinotecan-related diarrhea due to higher frequence of UGT1A A1 * 28 wild genotype TA6/6.

Background: To investigate whether the pharmacodynamics and pharmacokinetics of omeprazole (OPZ) are dependent of the CYP2C19 genotype status in Chinese people., Methods: Eighteen healthy subjects were voluntary to participate in the study, whose CYP2C19 genotype status were determined by polymerase chain reaction-restriction fragment length polymorphism method. There were six homozygous extensive metabolizers, six heterozygous extensive metabolizers and six poor metabolizers (PMs). All subjects were Helicobacter pylori-negative, determined by serology method and (13)C-urea breath test. After d1 and d8 orally received OPZ 20 mg once daily in the morning, intragastric pH values were monitored for 24 h by Digitrapper pH. Meanwhile, blood samples were collected at various time-points until 24 h after administration. The serum concentrations of OPZ were measured by liquid chromatography., Results: After single or repeated doses, the PMs showed a significantly higher mean area under the serum concentration-time curves (AUC) values than that observed in the homozygous extensive metabolizers or the heterozygous extensive metabolizers, with a relative ratio of 1.0 : 1.1 : 4.2 and 1.0 : 1.3 : 3.3 (homozygous extensive metabolizers:heterozygous extensive metabolizers:poor metabolizers), respectively. After a single dose of OPZ, significant differences in intragastric pH median, pH > 3 holding time and pH > 4 holding time were observed among the three groups. After repeated doses, the PMs showed a significantly higher intragastric pH values than that observed in the homozygous extensive metabolizers or the heterozygous extensive metabolizers., Conclusion: The pharmacodynamic effects of OPZ and its pharmacokinetics depend on the CYP2C19 genotype status in Chinese people.

Aim: To observe the pharmacokinetics and pharmaco-dynamics of rabeprazole and compare serum gastrin concentrations in different CYP2C19 genotype groups., Methods: The CYP2C19 genotype status of Chinese Han healthy volunteers was determined by polymerase chain reaction-restriction fragment length polymorphism method. Twenty H pylori-negative healthy subjects voluntary participated in the study. They were divided into the following three groups: homozygous extensive metabolizers (homEM), heterozygous extensive metabolizers (hetEM) and poor metabolizers (PM). After they orally received rabeprazole 20 mg once daily in the morning of d 1 and d 8, blood samples were collected at various time-points until 24 h after administration and intragastric pH values were monitored for 24 h by Digitrapper pH. Serum gastrin concentrations were measured by radioimmunoassay. Serum concentrations of rabeprazole were measured by high performance liquid chromatography., Results: The mean AUC values for rabeprazole after a single and repeated doses were significantly different between the homEM and PM groups, but not between the homEM and hetEM, or the hetEM and PM groups. No significant differences in intragastric pH medians were observed among the three different genotype groups after a single dose or repeated doses. The ratio of pH medians between d 1 and d 8 ranged from 84% to 108%. The mean gastrin AUC values were also different among the three genotype groups, with a relative ratio of 1.0, 1.2 and 1.5 after a single dose and 1.0, 1.5 and 1.6 after repeated doses in the homEM, hetEM and PM groups, respectively. The gastrin AUC values among the three different genotype groups showed no significant difference either after a single dose or repeated doses. The subject who had lower intragastric acidity showed higher serum gastrin levels and concentrations of rabeprazole., Conclusion: In Chinese Han healthy people, the pharmacokinetics of rabeprazole are dependent on the CYP2C19 genotype status, but acid-inhibitory efficacy of rabeprazole and the gastrin level are not influenced significantly.

Many epidemiologists have agreed that a refined estimate of the incubation period of severe acute respiratory syndrome (SARS) would need a sample size of about 200 cases and appropriate statistical methods enabling the inclusion of cases with defined periods of exposure. However, no such studies have been reported so far. Besides, determinants of the SARS incubation period remain unclear. In this study, 209 probable SARS cases with documented episodes of exposure between March 1 and May 31, 2003, in mainland China were included. A nonparametric method was used to analyze these data with defined periods of exposure to obtain the refined estimate of the SARS incubation period. Furthermore, the authors also explored the influence of various factors on the SARS incubation period by analysis of variance, linear regression analysis, and analysis of covariance. The estimates of mean and variance of the SARS incubation period were 5.29 days and 12.33 days(2), respectively; 90% of patients would have an incubation period of less than 11.58 days with a probability of 0.8, and 99% of patients would have an incubation of less than 22.22 days with a probability of 0.9. The affected area showed a highly significant effect on the incubation period (p < 0.001), but the contact pattern, occupation, gender, and age did not.

Aim: To investigate whether the pharmacodynamics and pharmacokinetics of rabeprazole are dependent on CYP2C19 genotype status in healthy Chinese Han subjects., Methods: The CYP2C19 genotype status of healthy Chinese Han volunteers was determined using the polymerase chain reaction-restriction fragment length polymorphism method. Twenty healthy subjects volunteered to participate in the study. There were seven homozygous extensive metabolizers (homEM), six heterozygous extensive metabolizers (hetEM), and seven poor metabolizers (PM). All subjects were Helicobactor pylori-negative, which was determined by sero-logy and 13C-urea breath tests. Rabeprazole (20 mg) was taken orally once daily in the morning for 8 days, and intragastric pH values were monitored for 24 h by Digitrapper pH after day 1 (single dose) and day 8 (repeated dose). Meanwhile, blood samples were collected at various time-points for 24 h after administration. The serum concentrations of rabeprazole were measured using high-performance liquid chromatography., Results: The mean area under the curve (AUC) values for rabeprazole differed among the three different genotype groups, with a relative ratio of 1.0, 1.3, and 1.8 after a single dose and 1.0, 1.1, and 1.7 after repeated doses in the homEM, hetEM, and PM groups, respectively. Mean AUC values for rabeprazole after a single dose and after repeated doses were significantly different between the homEM and PM groups, but not between the homEM and hetEM or hetEM and PM groups. No significant differences in intragastric pH median, pH>4 total time, and pH>4 time percentage of 24 h, were observed among the three different genotype groups after a single dose or after repeated doses of rabeprazole., Conclusion: In healthy Chinese Han subjects, the pharmacokinetics of rabeprazole are dependent on a certain degree on CYP2C19 genotype status; however, the acid-inhibitory efficacy of rabeprazole is not influenced significantly by CYP2C19 genetic polymorphism.