the early-stage GC group. ROC curves for the diagnostic cutoffs of PGI, PGR, and G17 in GC ROC curves of PGI, PGR, and G17 for early-stage GC diagnosis are shown in Figure 1a and b, with early-stage GC as the disease group ( em n /em ?=?5) and non-atrophic gastritis, atrophic gastritis, and peptic ulcers as references ( em n /em ?=?936). and (4) complications associated with severe heart, lung, and kidney diseases. This study was approved by the Ethical Committee of Qinghai Provincial Peoples Hospital (Xining, China) in October 2013. All participants volunteered to participate in this study and signed informed consent forms prior to entering the study. Screening procedures The demographics (including name, age, gender, history of digestive tract diseases, drug use, GC surgery, family history of GC, diet, and lifestyle) of participants were obtained by paper-and-pencil questionnaires. Fasting blood samples (5?mL) were collected and separated by centrifugation for 5 minutes at 500? Capn1 em g /em , and then stored at ?80C. Serum levels of PGI, PGII, and G17 were detected using ELISA kits (Biohit, Helsinki, Finland) following the manufacturers instructions; these results were also used to calculate the PGI to PGII ratio (PGR). Participants with serum PGI (80C165?g/L), PGII (3C15?g/L), or G17 (1C15?pmol/L) were further examined by gastroscopy according to national diagnostic standards. Diagnosis and grouping Participants diagnosed by gastroscopy were further divided into five groups based on gastroscopic and histopathological results: (1) non-atrophic gastritis; (2) atrophic gastritis; (3) peptic ulcer; (4) early-stage GC; and (5) progressive GC. Statistical analysis All statistical analyses were performed with SPSS Statistics for Windows, Version 17.0 (SPSS Inc., Chicago, IL, USA). The data are expressed as mean??SD. Differences were compared by one-way analysis of variance (ANOVA) for continuous variables, followed by the least significant difference (LSD) post-hoc test for multiple comparisons, or by the Chi-squared test for categorical data. The optimal serum PGI, PGII, and G17 levels for diagnosing GC were determined by receiver operating characteristic (ROC) curves. em P /em ? ?0.05 was considered statistically significant. Results Gastroscopic results of participants at a high risk for GC Among the 20,000 local residents surveyed, 2,500 had upper digestive tract symptoms (including abdominal distension, abdominal pain, acid regurgitation, heartburn, nausea, and loss of appetite) or family histories of GC, indicating that they had a high risk of GC. Among them, 1,096 were men and 1,404 were women, with an average age of 50.66??11.34 years. Additionally, 949 (37.96%) underwent gastroscopy and 649 (25.96%) underwent biopsy diagnoses. The gender, age, and ethnic distributions of participants examined by gastroscopy are shown in Tables 1 and ?and2.2. Only 13 of these 949 participants (1.37%) had GC, including five cases of early-stage GC (38.5%) and eight cases of progressive GC (61.5%). We performed endoscopic submucosal dissection (ESD) in cases of early-stage GC, and all showed good recovery in postoperative follow-up. Table 1. Histological diagnoses by gastroscopy. thead valign=”top” th rowspan=”1″ colspan=”1″ Pathological type /th th rowspan=”1″ colspan=”1″ Number (%) /th th rowspan=”1″ colspan=”1″ Gender (male/female) /th th rowspan=”1″ colspan=”1″ Age (years) /th /thead Non-atrophic gastritis239 (25.18)95/14448.48??7.38Atrophic gastritis500 (52.69)231/26945.02??8.11Peptic ulcer197 (20.76)113/8451.76??7.98Early-stage GC5 (0.53)3/254.40??9.91Progressive GC8 (0.84)2/650.25??8.99Total949 (100)443/50649.83??8.40 Open in a separate window Note: GC, gastric cancer. Table 2. Ethnic distribution of participants examined by gastroscopy. thead valign=”top” th rowspan=”1″ colspan=”1″ Pathological types /th th rowspan=”1″ colspan=”1″ Han /th th rowspan=”1″ colspan=”1″ Hui /th th rowspan=”1″ colspan=”1″ Tu /th th rowspan=”1″ colspan=”1″ Tibetan /th /thead Non-atrophic gastritis12693173Atrophic gastritis360118148Peptic ulcer10973150Early-stage GC2300Progressive GC3500Total6002924611 Open in a separate window Note: GC, Gastric Cancer. Serum PGI, 9-Dihydro-13-acetylbaccatin III PGII, and G17 levels in each group PGI and PGR levels were lower in the atrophic gastritis, early-stage GC, and progressive GC groups compared with the non-atrophic gastritis group as a control ( em P /em ? ?0.05). G17 levels were higher in those with early-stage GC and progressive GC ( em P /em ? ?0.05). The progressive GC group had lower PGI and PGR levels and higher G17 levels than the early-stage GC group ( em P /em ? ?0.05, Table 3). Table 3. Serum PGI, PGII, PGR, and G17 levels in different groups ( math xmlns:mml=”http://www.w3.org/1998/Math/MathML” id=”mml-math1-0300060520914826″ mrow mover accent=”true” mi x /mi mo stretchy=”true” /mo /mover /mrow /math ??s). thead valign=”top” th rowspan=”1″ colspan=”1″ Group /th th rowspan=”1″ colspan=”1″ em n /em /th th rowspan=”1″ colspan=”1″ PGI (g/L) /th th rowspan=”1″ colspan=”1″ PGII (g/L) /th th rowspan=”1″ colspan=”1″ PGR /th th rowspan=”1″ colspan=”1″ G17 (g/L) /th /thead Non-atrophic gastritis239103.89??37.4513.37??7.689.18??4.1014.99??7.12Atrophic gastritis50068.73??16.98*13.48??8.487.03??4.55*12.29??6.00Peptic ulcer197130.52??44.09*16.58??7.34*8.98??4.0311.95??5.40*Early-stage GC570.00??12.35*20.86??7.74*3.74??1.40*18.03??4.52*Progressive GC838.39??2.77*,#20.73??8.09*2.05??0.59*,#25.15??3.76*,# Open in a separate window Note: GC, gastric cancer; PGI, pepsinogen I; PGII, pepsinogen II; PGR, PGI to PGII ratio; G17, gastrin-17. * em P /em ? ?0.05 vs. the non-atrophic gastritis group; # em P /em ? ?0.05 vs. the early-stage GC group. ROC curves for the diagnostic cutoffs of PGI, PGR, and G17 in GC ROC curves of PGI, PGR, and G17 for early-stage GC diagnosis are shown in.(a) ROC curves of pepsinogen (PG) I and the PGI to PGII ratio (PGR) for diagnosing early-stage GC. of early-stage GC, respectively, and were 42.55 g/L, 20.55 pmol/L, and 2.79 for the diagnosis of progressive GC, respectively. Conclusion Combining PG and G17 serum levels with gastroscopy could be a promising approach to screen for early-stage GC. infection; and (4) complications associated with severe heart, lung, and kidney diseases. This study was approved by the Ethical Committee of Qinghai Provincial Peoples Hospital (Xining, China) in October 2013. All participants volunteered to participate in this study and signed informed consent forms prior to entering the study. Screening procedures The demographics (including name, age, gender, history of digestive tract diseases, drug use, GC surgery, family history of GC, diet, and lifestyle) of participants were obtained by paper-and-pencil questionnaires. Fasting blood samples (5?mL) were collected and separated by centrifugation for 5 minutes at 500? em g /em , and then stored at ?80C. Serum levels of PGI, PGII, and G17 were detected using ELISA kits (Biohit, Helsinki, Finland) following the manufacturers instructions; these results were also used to calculate the PGI to PGII ratio (PGR). Participants with serum PGI (80C165?g/L), PGII (3C15?g/L), or G17 (1C15?pmol/L) were further examined by gastroscopy according to national diagnostic standards. Diagnosis and grouping Participants diagnosed by gastroscopy were further divided into five groups based on gastroscopic and histopathological results: (1) non-atrophic gastritis; (2) atrophic gastritis; (3) peptic ulcer; (4) early-stage GC; and (5) progressive GC. Statistical analysis All statistical analyses were performed with SPSS Statistics for Windows, Version 17.0 (SPSS Inc., Chicago, IL, USA). The data are expressed as mean??SD. Differences were compared by one-way analysis of variance (ANOVA) for continuous variables, followed by the least significant difference (LSD) post-hoc test for multiple comparisons, or by the Chi-squared test for categorical data. The optimal serum PGI, PGII, and G17 levels for diagnosing GC were determined by receiver operating characteristic (ROC) curves. em P /em ? ?0.05 was considered statistically significant. Results Gastroscopic results of participants 9-Dihydro-13-acetylbaccatin III at a high risk for GC Among the 20,000 local residents surveyed, 2,500 had upper digestive tract symptoms (including abdominal distension, abdominal pain, acid regurgitation, heartburn, nausea, and loss of appetite) or family histories of GC, indicating that they had a high risk of GC. Among them, 1,096 were men and 1,404 were women, with an average age of 50.66??11.34 years. Additionally, 949 (37.96%) underwent gastroscopy and 649 (25.96%) underwent biopsy diagnoses. The gender, age, and ethnic distributions of participants examined by gastroscopy are shown in Tables 1 and ?and2.2. Only 13 of these 949 participants (1.37%) had GC, including five cases of early-stage GC (38.5%) and eight cases of progressive GC (61.5%). We performed endoscopic submucosal dissection (ESD) in cases of early-stage GC, and all showed good recovery in postoperative follow-up. Table 1. Histological diagnoses by gastroscopy. thead valign=”top” th rowspan=”1″ colspan=”1″ Pathological type /th th rowspan=”1″ colspan=”1″ Number (%) /th th rowspan=”1″ colspan=”1″ Gender (male/female) /th th rowspan=”1″ colspan=”1″ Age (years) /th /thead Non-atrophic gastritis239 (25.18)95/14448.48??7.38Atrophic gastritis500 (52.69)231/26945.02??8.11Peptic ulcer197 (20.76)113/8451.76??7.98Early-stage GC5 (0.53)3/254.40??9.91Progressive GC8 (0.84)2/650.25??8.99Total949 (100)443/50649.83??8.40 Open in a separate window Note: GC, gastric cancer. Table 2. Ethnic distribution of participants examined by gastroscopy. thead valign=”top” th rowspan=”1″ colspan=”1″ Pathological types /th th rowspan=”1″ colspan=”1″ Han /th th rowspan=”1″ colspan=”1″ Hui /th th rowspan=”1″ colspan=”1″ Tu /th th rowspan=”1″ colspan=”1″ Tibetan /th /thead Non-atrophic gastritis12693173Atrophic gastritis360118148Peptic ulcer10973150Early-stage GC2300Progressive GC3500Total6002924611 Open in a separate window Note: GC, Gastric Cancer. Serum PGI, PGII, and G17 levels in each group PGI and PGR levels were lower in the atrophic gastritis, early-stage GC, and progressive GC groups compared with the non-atrophic gastritis group as a control ( em P /em ? ?0.05). G17 levels were higher in those with early-stage GC and progressive GC ( em P /em ? ?0.05). The progressive GC group had lower PGI and PGR levels and higher G17 levels than the early-stage GC group ( em P /em ? ?0.05, Table 3). Table 3. Serum PGI, PGII, PGR, and G17 levels in different groups ( math xmlns:mml=”http://www.w3.org/1998/Math/MathML” id=”mml-math1-0300060520914826″ mrow mover accent=”true” mi x /mi mo stretchy=”true” /mo /mover /mrow /math ??s). thead valign=”top” th rowspan=”1″ colspan=”1″ Group /th th rowspan=”1″ colspan=”1″ em n /em /th th rowspan=”1″ colspan=”1″ PGI (g/L) /th th rowspan=”1″ colspan=”1″ PGII (g/L) /th th rowspan=”1″ colspan=”1″ PGR /th th rowspan=”1″ colspan=”1″ G17 (g/L) /th /thead Non-atrophic gastritis239103.89??37.4513.37??7.689.18??4.1014.99??7.12Atrophic gastritis50068.73??16.98*13.48??8.487.03??4.55*12.29??6.00Peptic ulcer197130.52??44.09*16.58??7.34*8.98??4.0311.95??5.40*Early-stage GC570.00??12.35*20.86??7.74*3.74??1.40*18.03??4.52*Progressive GC838.39??2.77*,#20.73??8.09*2.05??0.59*,#25.15??3.76*,# Open in a separate window Note: GC, gastric cancer; PGI, pepsinogen I; 9-Dihydro-13-acetylbaccatin III PGII, pepsinogen II; PGR, PGI to PGII ratio; G17, gastrin-17. * em P /em ? ?0.05 vs. the non-atrophic gastritis group; # em P /em ? ?0.05 vs. the early-stage GC group. ROC curves for the diagnostic cutoffs of PGI, PGR, and G17 in.