Identification of key potential infection processes and risk factors in the computed tomography examination process by FMEA method under COVID-19.

PURPOSE: To identify the key infection processes and risk factors in Computed Tomography (CT) examination process within the standard prevention and control measures for the COVID-19 epidemic, aiming to mitigate cross-infection occurrences in the hospital. METHOD: The case hospital has assembled a team of 30 experts specialized in CT examination. Based on the CT examination process, the potential failure modes were assessed from the perspective of severity (S), occurrence probability (O), and detectability (D); they were then combined with corresponding risk prevention measures. Finally, key infection processes and risk factors were identified according to the risk priority number (RPN) and expert analysis. RESULTS: Through the application of RPN and further analysis, four key potential infection processes were identified, including "CT request form (A1)," "during the scan of CT patient (B2)," "CT room and objects disposal (C2)," and "medical waste (garbage) disposal (C3)". In addition, eight key risk factors were also identified, including "cleaning personnel does not wear masks normatively (C32)," "nurse does not select the vein well, resulting in extravasation of the peripheral vein for enhanced CT (B25)," "patient cannot find the CT room (A13)," "patient has obtained a CT request form but does not know the procedure (A12)," "patient is too unwell to continue with the CT scan (B24)," "auxiliary staff (or technician) does not have a good grasp of the sterilization and disinfection standards (C21)," "auxiliary staff (or technician) does not sterilize the CT machine thoroughly (C22)," and "cleaning personnel lacks of knowledge of COVID-19 prevention and control (C33)". CONCLUSION: Hospitals can publicize the precautions regarding CT examination through various channels, reducing the incidence of CT examination failure. Hospitals' cleaning services are usually outsourced, and the educational background of the staff employed in these services is generally not high. Therefore, during training and communication, it is more necessary to provide a series of scope and training programs that are aligned with their understanding level. The model developed in this study effectively identifies the key infection prevention process and critical risk factors, enhancing the safety of medical staff and patients. This has significant research implications for the potential epidemic of major infectious diseases.

Effects of Infrasound on Gastric Motility, Gastric Morphology and Expression of Nitric Oxide Synthase in Rat.

Infrasound widely exists in nature, our living condition, productive and traffic environment. Gastrointestinal tract is relatively sensitive to infrasound. However, the effect of infrasound on gastrointestinal function is unclear. Therefore, the purpose of our study was to observe the effects of infrasound on gastric motility and gastric morphology and to assess the expression of nitric oxide synthase (NOS) in gastric antrum after exposure to infrasound of 8 Hz - 130 dB for 2 hours per day for 14 consecutive days. Gastric motility was assessed by gastric fluid-emptying rate. Gastric morphology was evaluated by HE. The expression of NOS was measured by tissue microarray technology. The results would contribute to understand the role of infrasound in gastroenterology, and help to explain the mechanism of infrasound on gastroenterology.

Possible role of mast cells and neuropeptides in the recovery process of dextran sulfate sodium-induced colitis in rats.

OBJECTIVE: To clarify the role of mast cells and neuropeptides substance P (SP), somatostatin (SS), and vasoactive intestinal peptide (VIP) in dextran sulfate sodium (DSS)-induced colitis in rats. METHODS: Experimental colitis was induced in Sprague-Dawley rats (180-200 g, n=20) by oral ingestion of 4% (w/v) DSS in drinking water for 7 days. Control rats (n=5) drank water and were sacrificed on day 0. Mast cell number, histamine levels in whole blood and tissue, tissue levels of SP, SS and, VIP in the distal colon of the rats were measured on day 8, day 13, and day 18 of experimentation. RESULTS: Oral administration of 4% DSS solution for 7 days resulted in surface epithelial loss and crypt loss in the distal colon. Mast cell count increased on day 8 (1.75±1.09/mm vs. 0.38±0.24/mm, P<0.05) and day 13 (1.55±1.01/mm vs. 0.38±0.24/mm, P<0.05) after DSS treatment. Whole blood histamine levels were increased on day 8 (266.93±35.62 ng/mL vs. 76.87±32.28 ng/mL, P<0.01) and gradually decreased by day 13 and day 18 after DSS treatment. Histamine levels in the distal colon were decreased on day 8 (1.77±0.65 ng/mg vs. 3.06±0.87 ng/mg, P<0.05) and recovered to control levels by day 13 after DSS treatment. SP level in the distal colon gradually increased and were raised significantly by day 13 (8777.14±3056.14 pg/mL vs. 4739.66±3299.81 pg/mL, P<0.05) after DSS treatment. SS and VIP levels in the distal colon were not changed. CONCLUSIONS: Mast cell degranulation followed by histamine release may play an important role in the pathogenesis of colitis induced by DSS. SP may be a significant substance in the progression of inflammation and the recovery process of DSS-induced colitis.

Incidence of gastroesophageal reflux disease in Uygur and Han Chinese adults in Urumqi.

AIM: To investigate the incidence of gastroesophageal reflux disease (GERD) and its related risk factors in Uygur and Han Chinese adult in Urumqi, China. METHODS: A population-based cross-sectional survey was undertaken in a total of 972 Uygur (684 male and 288 female) aged from 24 to 61 and 1023 Han Chinese (752 male and 271 female) aged from 23 to 63 years. All participants were recruited from the residents who visited hospital for health examination from November 2011 to May 2012. Each participant signed an informed consent and completed a GERD questionnaire (Gerd Q) and a lifestyle-food frequency questionnaire survey. Participants whose Gerd Q score was ≥ 8 and met one of the following requirements would be enrolled into this research: (1) being diagnosed with erosive esophagitis (EE) or Barrett's esophagus (BE) by endoscopy; (2) negative manifestation under endoscopy (non-erosive reflux disease, NERD) with abnormal acid reflux revealed by 24-h esophageal pH monitoring; and (3) suffering from typical heartburn and regurgitation with positive result of proton pump inhibitor test. RESULTS: According to Gerd Q scoring criteria, 340 cases of Uygur and 286 cases of Han Chinese were defined as GERD. GERD incidence in Uygur was significantly higher than in Han Chinese (35% vs 28%, χ(2) = 11.09, P < 0.005), Gerd Q score in Uygur was higher than in Han Chinese (7.85 ± 3.1 vs 7.15 ± 2.9, P < 0.005), and Gerd Q total score in Uygur male was higher than in female (8.15 ± 2.8 vs 6.85 ± 2.5, P < 0.005). According to normalized methods, 304 (31%) cases of Uygur were diagnosed with GERD, including 89 cases of EE, 185 cases of NERD and 30 cases of BE; 256 (25%) cases of Han Chinese were diagnosed with GERD, including 90 cases of EE, 140 cases of NERD and 26 cases of BE. GERD incidence in Uygur was significantly higher than in Han Chinese (31% vs 25%, χ(2) = 9.34, P < 0.005) while the incidences were higher in males of both groups than in females (26% vs 5% in Uygur, χ(2) = 35.95, P < 0.005, and 19.8% vs 5.2% in Han, χ(2) = 5.48, P < 0.025). GERD incidence in Uygur male was higher than in Han Chinese male (26% vs 19.8%, χ(2) = 16.51, P < 0.005), and incidence of NERD in Uygur was higher than in Han Chinese (χ(2) = 10.06, P < 0.005). Occupation (r = 0.623), gender (r = 0.839), smoking (r = 0.322), strong tea (r = 0.658), alcohol drinking (r = 0.696), meat-based diet (mainly meat) (r = 0.676) and body mass index (BMI) (r = 0.567) were linearly correlated with GERD in Uygur (r = 0.833, P = 0.000); while gender (r = 0.957), age (r = 0.016), occupation (r = 0.482), strong tea (r = 1.124), alcohol drinking (r = 0.558), meat diet (r = 0.591) and BMI (r = 0.246) were linearly correlated with GERD in Han Chinese (r = 0.786, P = 0.01). There was no significant difference between Gerd Q scoring and three normalized methods for the diagnosis of GERD. CONCLUSION: GERD is highly prevalent in adult in Urumqi, especially in Uygur. Male, civil servant, smoking, strong tea, alcohol drinking, meat diet and BMI are risk factors correlated to GERD.

[Changes of mast cells and gut hormones in rats with TNBS-induced ulcerative colitis].

OBJECTIVE: To investigate the role of mast cells and gut hormones and their interactions in TNBS-induced ulcerative colitis. METHODS: Rat models of ulcerative colitis were established by a single intracolonic injection of 100 mg/kg TNBS (in 0.3 ml 50% ethanol). At 0, 6, 11, 16, 21 days after TNBS injection, the rats were sacrificed to determine the count of the mast cells. Histamine level in the whole blood, and the levels of histamine, substance P (SP), vasoactive intestinal peptide (VIP), and somatostatin (SS) in the distal colons were measured by fluorimetry or radioimmune assay. Immunofluorescence double staining was used to observe the relationship of the mast cells with SP, VIP, and SS positive nerve fibers. RESULTS: On day 6 after TNBS injection, obvious ulcers occurred in the distal colon of the rats with significantly increased histamine level in the whole blood (P<0.05) but significantly decreased colonic histamine levels (P<0.05). The histamine levels in the whole blood and distal colon gradually recovered the normal levels. The mast cells significantly increased on day 16 (P<0.05) and maintained the high level till day 21. The distribution of mast cells was altered after TNBS injection, and the cells were found to aggregate in the myenteric region. SP levels in the distal colon significantly increased on day 11 (P<0.05) and maintained the high level till day 21. Immunofluorescence double staining revealed numerous mast cells close to the SP- and VIP-positive nerve fibers at different time points after TNBS injection. VIP positivity and the number of VIP-positive nerve fibers in the myenteric region were markedly increased, but no mast cells were observed in association with SP- and VIP-positive nerve fibers. The distribution of MC was not found to associate with the SS-positive nerve fibers. CONCLUSION: The mast cells and histamine released by them, as well as parasecretion of SP and VIP, participate in tissue damage by TNBS-induced colitis. Bidirectional neuroimmunomodulation of the mast cells, SP and VIP have important effect on the development of TNBS-induced colitis.

[A research of migrating motor complex in patients with irritable bowel syndrome].

OBJECTIVES: To compare the migrating motor complex (MMC) in irritable bowel syndrome (IBS) patients with that in healthy controls. To explore whether discrete clustered contractions (DCC) are connected with abdominal pain in IBS patients. To improve the method of measuring gastroenteric motility (esp. jejunum). METHODS: By using 16-channel water-perfused catheter and manometry instruments, MMC in 16 cases of IBS with constipation (IBS-C), 18 cases of IBS with diarrhea (IBS-D) and 18 cases of healthy controls were monitored. RESULTS: The MMC durations of IBS-C and IBS-D patients were (127.5 +/- 25.5) min and (74.5 +/- 18.7) min, respectively. Comparision with those in the control group [(87.5 +/- 24.2) min] showed significant differences (P < 0.001). The contraction amplitudes of stage III in different sites of IBS-C patients decreased significantly as compared with those in the controls [jejunum, (39.8 +/- 11.7) mm Hg vs. (61.1 +/- 14.1) mm Hg, P < 0.001, 1 mm Hg = 0.133 kPa]. The propagation velocities of stage III in different sites of IBS-C patients also decreased significantly as compared with those in the controls [jejunum, (1.8 +/- 0.9) cm/min vs. (2.6 +/- 0.8) cm/min, P < 0.01]. The contraction amplitudes of stage III in different sites of IBS-D patients increased significantly as compared with those in the controls [jejunum, (69.7 +/- 20.5) mm Hg vs. (61.1 +/- 14.1) mm Hg, P < 0.01]. The propagation velocities of stage III in different sites of IBS-D patients also increased significantly as compared with those in the controls [jejunum, (4.1 +/- 2.5) cm/min vs. (2.6 +/- 0.8) cm/min, P < 0.01]. DCC incidences of IBS-C and IBS-D were 87.5% and 88.8%, respectively. Comparision with those in the normal group (83.3%) did not show significant difference (P > 0.05). The prevalences of abnormal stage III contractions (include disturbances and interferences of stage III contractions) in IBS-C and IBS-D patients were 68.8% and 66.7%, respectively; there were no significant differences between the two groups (P > 0.05). However abnormal stage III contractions did not exist in healthy controls. CONCLUSIONS: (1) The MMC of IBS-C and IBS-D patients are changed, as compared with that in healthy people; this implies that small intestinal motility dysfunction is one of the pathogenetic factors of IBS. The abnormal stage III contractions in jejunum may be a predominant change in IBS gastroenteric motility. (2) No apparent connection is found between DCC and pain in IBS. (3) By using 16-channel water-perfused catheter, we first carried out the method of monitoring jejunum contractions in China. Parameters of MMC in Chinese healthy people were investigated, esp. those of jejunum.

[Long-term impact on quality of life in patients with gastroesophageal reflux disease after 52-week rabeprazole treatment].

OBJECTIVE: To investigate the longitudinal changes in quality of life (QoL) for gastroesophageal reflux disease (GERD) treated with 52-week rabeprazole over a period of 2-3 years. METHODS: A multi-center, open-label and randomized 52-week rabeprazole trial was conducted in 67 eosinophilic esophagitis (EE) and 31 non-erosive reflux disease (NERD) patients. The follow-up period is 2-3 years after the treatment. Their QoL were evaluated using SF-36 Health Survey Questionnaire and GERD-HRQL scale. The results were compared with those acquired before and after a 52-week proton pump inhibitor (PPI) treatment. RESULTS: (1) Both EE and NERD patients improved significantly according to GERD-HRQL scale in scores of reflux symptoms as well as overall satisfaction (12.5 vs 3.5, 20.0 vs 14.0, both P < 0.01) versus the pre-therapy baseline. (2) Both EE and NERD patients had no significant difference in the scale of GERD-HRQL (2.0 vs 3.5, 5.0 vs 4.0, both P > 0.05) and most major domains of SF-36 questionnaire versus the post-therapy baseline (53 +/- 17 vs 61 +/- 17, t = -2.143, P = 0.035). (3) The NERD patients had a higher score of reflux symptoms than the EE patients according to the GERD-HRQL Scale (14.0 vs 3.5, Z = 2.377, P = 0.017), however there were no significant differences between NERD and EE in 8 major domains of SF-36 questionnaire (P > 0.05). CONCLUSION: Long-term and low-dose PPI treatment achieves improvement both in reflux symptoms and QoL in GERD patients and such effects last a long time. At follow-ups, the reflux symptoms of NERD patients are more severe than EE patients. However, the overall QoL has shown little differences between these two subtypes.

Decreased expression of serotonin in the jejunum and increased numbers of mast cells in the terminal ileum in patients with irritable bowel syndrome.

AIM: To investigate if there are changes in serotonin (5-HT) levels, enterochromaffin (EC) cells and mast cells in small intestinal mucosa of patients with irritable bowel syndrome (IBS). METHODS: Diarrhea-predominant (IBS-D, n = 20), or constipation-predominant (IBS-C, n = 18) IBS patients and healthy controls (n = 20) underwent colonoscopy and peroral small intestinal endoscopy, and mucosal samples were obtained at the descending part of the duodenum, proximal end of jejunum and terminal ileum. High-performance liquid chromatography-electrochemistry and immunohistochemical methods were used to detect 5-HT content, EC cells and mast cells. RESULTS: (1) There were no differences in the number and distribution of EC cells between IBS patients and the normal group. (2) The mucosal 5-HT contents at the duodenum, jejunum and ileum in IBS-C patients were 182 +/- 90, 122 +/- 54, 61 +/- 35 ng/mg protein, respectively, which were all lower than those in the normal group (256 +/- 84, 188 +/- 91, and 93 +/- 45 ng/mg protein, respectively), with a significant difference at the jejunum (P < 0.05). There were no differences in the small intestinal mucosal 5-HT contents between IBS-D patients and the normal group. The mucosal 5-HT contents at the duodenum were significantly higher than those at the ileum in the three groups (P < 0.001). (3) The numbers of mast cells in patients with IBS-C and IBS-D at the ileum were 38.7 +/- 9.4 and 35.8 +/- 5.5/high power field (hpf), respectively, which were significantly more than that in the normal group (29.8 +/- 4.4/hpf) (P < 0.001). There was no significant difference in the numbers of mast cells at the other two parts between IBS patients and the normal group. The numbers of mast cells in IBS-C, IBS-D, and normal groups were all significantly higher at the ileum (38.7 +/- 9.4, 35.8 +/- 5.5, 29.8 +/- 4.4/hpf, respectively) than at the duodenum (19.6 +/- 4.7, 18.5 +/- 6.3, 19.2 +/- 3.3/hpf, respectively, P < 0.001). CONCLUSION: The changes in the 5-HT signaling pathway at the jejunum of IBS-C patients and the increase in mast cells in patients with IBS at the terminal ileum may offer evidence to explain the pathogenesis of IBS.

A randomized, double-blind, placebo-controlled trial assessing the efficacy and safety of tegaserod in patients from China with chronic constipation.

AIM: To evaluate the efficacy and safety of tegaserod, 6 mg twice daily (b.i.d.), in men and women with chronic constipation (CC) from China. METHODS: This was a multicenter, double-blind, placebo-controlled study. Following a 2-wk treatment-free baseline period, patients were randomized to receive either tegaserod (6 mg b.i.d.) or placebo (b.i.d.) for 4 wk. An analysis of covariance with repeated measures was used to determine the overall effect of treatment for the primary efficacy variable; the change from baseline in the number of complete spontaneous bowel movements (CSBMs) during the 4-wk treatment period. Secondary efficacy endpoints included other measures of response in terms of CSBMs, and patients' daily and weekly assessment of bowel habits. Safety was also assessed, based on the incidence and severity of adverse events (AEs). RESULTS: A total of 607 patients were randomized to receive either tegaserod (n = 304) or placebo (n = 303). Tegaserod treatment resulted in a rapid and significant increase from baseline in the adjusted mean number of CSBMs per week over wk 1-4 compared with placebo (1.39 vs 0.91, P = 0.0002). A statistically significant difference in favor of tegaserod was also observed for a mean increase > or = 1 CSBM/wk over wk 1-4 (47.7% vs 35.0%, tegaserod vs placebo, respectively, P = 0.0018) and for the absolute number of > or = 3 CSBMs/wk over wk 1-4 (25.0% vs 14.5%, tegaserod vs placebo, respectively, P = 0.0021). Improvements in other symptoms of CC were also seen in the tegaserod group, including improved stool form and reduced straining. In addition, more patients in the tegaserod group reported satisfactory relief from their constipation symptoms. The frequency and severity of AEs was comparable between tegaserod and placebo groups, with the exception of a greater incidence of diarrhea in patients receiving tegaserod (3.6%) compared with placebo (1.7%). CONCLUSION: Tegaserod treatment improved multiple symptoms of CC and was associated with a favorable safety profile.

[Investigation on the health-related quality of life among 411 patients with irritable bowel syndrome].

OBJECTIVE: To evaluate and compare the health-related quality of life (HRQOL) on patients with irritable bowel syndrome (IBS). METHODS: Following the Rome III Criteria, 411 IBS patients and 430 healthy people were selected as subjects,who were outpatients in Department of Gastroenterology, 2nd Hospital of Xi' an Jiaotong University and Shaanxi Provincial People's Hospital from July 2006 to April 2007. Using the 36-Item Short-Form Health Survey (SF-36). This study compared the SF-36 scale scores of IBS patients with the healthy people. RESULTS: On all of the 8 SF-36 scales, patients with IBS scored significantly lower than healthy people (P < 0.001). Decrements in HRQOL were most predominant in general health perception and role limitations caused by emotional health problem, with scores of 33.5 + 16.9, 40.8 +/- 25.1 respectively. The emotional well-being and energy/fatigue scale scores were also quite low (42.2 +/- 19.3,43.1 +/- 20.2,respectively). They also scored significantly lower on both physical summary. and mental summary scores (P < 0.001). IBS patients were classified into IBS with constipation,IBS with diarrhea, mixed IBS and unsubtyped IBS subgroups, with percentages as 25.3%, 50.1%, 11.2% and 13.4% respectively. CONCLUSION: IBS patients experienced great impairment in HRQOL. These data offered further insight into the impact of IBS on patient functional status and well-being.

Molecular forms of trefoil factor 1 in normal gastric mucosa and its expression in normal and abnormal gastric tissues.

AIM: To study the molecular forms of trefoil factor 1 (TFF1) in normal gastric mucosa and its expression in normal and abnormal gastric tissues (gastric carcinoma, atypical hyperplasia and intestinalized gastric mucosa) and the role of TFF1 in the carcinogenesis and progression of gastric carcinoma and its molecular biological mechanism underlying gastric mucosa protection. METHODS: The molecular forms of TFF1 in normal gastric mucosa were observed by Western blot. The expression of TFF1 in normal and abnormal gastric tissues (gastric carcinoma, atypical hyperplasia and intestinalized gastric mucosa) was also assayed by immunohistochemical method. The average positive AO was estimated by Motic Images Advanced 3.0 software. RESULTS: Three patterns of TFF1 were found in normal gastric mucosa: monomer, dimmer, and TFF1 compound whose molecular weight is about 21 kDa. The concentration of TFF1 compound was the highest among these three patterns. TFF1 was expressed mainly in epithelial cytoplasm of the mucosa in gastric body and antrum, especially around the nuclei. The closer the TFF1 to the lumen, the higher the expression of TFF1. The expression of TFF1 in peripheral tissue of gastric carcinoma (0.51 +/- 0.07) was higher than that in normal gastric mucosa (0.44 +/- 0.06, P < 0.001). The expression of TFF1 in gastric adenocarcinoma was positively related to the differentiation of adenocarcinoma. The lower the differentiation of adenocarcinoma was, the weaker the expression of TFF1. No TFF1 was expressed in poorly-differentiated adenocarcinoma. The expression of TFF1 in moderately-well differentiated adenocarcinoma (0.45 +/- 0.07) was a little lower than that in normal mucosa (P > 0.05). The expression of TFF1 in gastric mucosa with atypical hyperplasia (0.57 +/- 0.03) was significantly higher than that in normal gastric mucosa (P < 0.001). No TFF1 was expressed in intestinalized gastric mucosa. There was no statistically significant difference between the expressions of TFF1 in gastric mucosa around the intestinalized tissue (0.45 +/- 0.07) and normal gastric mucosa (P > 0.05). CONCLUSION: TFF1 is expressed mainly in epithelial cytoplasm of the mucosa in gastric body and antrum. Its main pattern is TFF1 compound, which may have a greater biological activity than monomer and dimer. The expression of TFF1 in peripheral mucosa of gastric ulcer is higher than that in mucosa 5 cm beyond the ulcer, indicating that TFF1 plays an important part in protection and restitution of gastric mucosa. The expression of TFF1 is increased in peripheral tissues of gastric carcinoma and gastric mucosa with atypical hyperplasia, but is decreased in cancer tissues, implying that TFF1 may be related to suppression and differentiation of carcinoma. The weaker expression of TFF1 in poorly-differentiated carcinoma may be related to the destruction of glands and cells in cancer tissues and the decrease in secretion of TFF1.

[Molecular forms of TFF1 in normal gastric mucosa and its relationship with canceration].

OBJECTIVE: To study the molecular forms of TFF1 in normal gastric mucosa and its expression in normal, gastric carcinoma, atypical hyperplasia, and intestinalized gastric mucosa. METHODS: The molecular forms of TFF1 in normal gastric mucosa was observed by western blotting. The expression of TFF1 in normal, gastric carcinoma, atypical hyperplasia, and intestinalization gastric mucosa was assayed immunohistochemically. RESULTS: TFF1 existed in normal gastric mucosa in forms of monomer, dimer and 21-kD TFF1 complex, with the last being the richest. TFF1 was expressed mainly in the epithelial cytoplasm of the mucosa in the gastric body and antrum, especially around the nucleus, and the closer to the lumen, the higher the expression. TFF1 expression in the tissues adjacent to gastric carcinoma was higher than that in normal gastric mucosa (P<0.001), and the expression in gastric adenocarcinoma was positively correlated to differentiation of adenocarcinoma. No TFF1 was expressed in poorly differentiated adenocarcinoma. The expression of TFF1 in moderate and well differentiated adenocarcinoma was a little lower than that in normal mucosa (P>0.05). The gastric mucosa with atypical hyperplasia had significantly higher TFF1 expression than normal gastric mucosa (P<0.001), and TFF1 was not detected in intestinalized gastric mucosa. There was no significant difference in TFF1 expression between gastric mucosa around the intestinalized tissues and normal gastric mucosa (P>0.05). CONCLUSIONS: TFF1 plays an important part in protection and restitution of the gastric mucosa, and TFF1 may be related to suppression and differentiation of carcinoma.

Effects of extract from Ginkgo biloba on carbon tetrachloride-induced liver injury in rats.

AIM: To study the effects of extract from Ginkgo biloba (EGb) containing 22% flavonoid and 5% terpenoid on chronic liver injury and liver fibrosis of rats induced by carbon tetrachloride (CCl(4)). METHODS: All rats were randomly divided into control group, CCl(4)-treated group, colchicine-treated group and EGb-protected group. Chronic liver injury was induced in experimental groups by subcutaneous injection of CCl(4) and fed with chows premixed with 79.5% corn powder, 20% lard and 0.5% cholesterol (v/v). EGb-protected group was treated with EGb (0.5 g/kg body weight per day) for 7 wk. At the end of wk 8, all the rats were killed. Liver function, liver fibrosis, oxidative stress and expression of transforming growth factor beta1 (TGF-beta1), a-smooth muscle actin (alpha-SMA) and type I collagens in liver were determined. In addition, pathology changes of liver tissue were observed under light microscope. RESULTS: The levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST) and albumin (Alb) in EGb-protected group were notably improved as compared with the CCl(4)-treated group (P < 0.01). The contents of serum hyaluronic acid (HA), type III procollagen (PCIII), type IV collagen (CIV) and the expression of hepatic tissue TGF-beta1, alpha-SMA and type I collagen in EGb-protected group were significantly lower than those in CCl(4)-treated groups (P < 0.05, P < 0.01). The degrees of liver fibrosis in EGb-protected groups were lower than those in CCl(4)-treated groups (6.58 +/- 1.25 vs 9.52 +/- 2.06, P < 0.05). Compared to the CCl(4)-treated group, the levels of plasma glutathoine peroxidase (Se-GSH-Px), superoxide dismutase (SOD) and malondialdehyde (MDA) were strikingly improved also in EGb-protected group (P < 0.05, P < 0.01). CONCLUSION: EGb resists oxidative stress and thereby reduces chronic liver injury and liver fibrosis in rats with liver injury induced by CCl(4).

Effect of change in an inhibitory neurotransmitter of the myenteric plexus on the pathogenetic mechanism of irritable bowel syndrome subgroups in rat models.

OBJECTIVE: In order to investigate the effect of change in an inhibitory neurotransmitter of the myenteric plexus on irritable bowel syndrome (IBS) subgroups, the amounts of nitric oxide (NO) in constipation-predominant (C-IBS) and diarrhea-predominant (D-IBS) IBS models in rats were studied. METHODS: The D-IBS model was created in rats by intracolonic instillation of acetic acid and by restraint stress. The D-IBS control group underwent intracolonic instillation with saline instead. The C-IBS model was created in rats by gastric instillation of 0-4 degrees C cool water daily for 14 days. The C-IBS control group underwent gastric instillation with saline instead. A blank control group was also made. Viscerosomatic sensitivity was assessed with electromyographic (EMG). Abdominal contractions induced by distension of a colonically inserted balloon (0-1.6 mL) was recorded in rats by implanting electrodes in the abdominal external oblique muscle. An India ink gastric instillation experiment was used to detect the bowel movement and fecal pellets formation. Histological analysis of colonic tissue was performed. Nicotinamide dinucleotide phosphate (NADPH)-diaphorase staining was used to detect positive NO neurons in the myenteric plexus. RESULTS: When the balloon was distended by high volume, there were significantly more contractions of abdominal muscle in D-IBS compared with C-IBS and the control groups (P < 0.05). When the balloon was distended by low volume, there were significantly fewer contractions of abdominal muscle in C-IBS compared with D-IBS and the control groups (P < 0.05). The wet weight and water content of the feces expelled by the rats in the C-IBS and the C-IBS control groups were significantly lower than those in the blank control group (P < 0.05). The time before the first black stool in the C-IBS group was significantly longer than that in the blank control group and C-IBS control group (P < 0.05). Histological analysis of the colon showed no colonic inflammation in any group. The number of NO-positive neurons in the C-IBS group was significantly greater than in the D-IBS and control groups (P < 0.01), although there was no significant difference in the number of neurons between the D-IBS and the control groups (P > 0.05). CONCLUSIONS: Enhanced inhibitory neurotransmitter NO in the myenteric plexus of the colon is related to IBS subgroups, visceral sensitivity and motility dysfunction. The results reveal that NO plays a role in the pathogenetic mechanism of IBS subgroups.

[Detecting the activity of antibodies induced by recombinant TGFbeta1 vaccine].

OBJECTIVE: To measure the neutralization activity in vitro of the antibodies induced by recombinant TGFbeta1 vaccine and to evaluate the vaccine's anti-liver fibrosis activity. METHODS: Balb/c mice were immunized with a fusion protein of the human TGFbeta1 epitope-inserted into a hepatitis B core antigen using a prokaryotic expression system. The antibody produced by the recombinant vaccine was determined using ELISA. The biological activity of the anti-TGFbeta1 antibody induced by the vaccine was measured by MTT using mink lung epithelial cell Mv-1-Lu as inhibiting cells. The fusion protein was used as a vaccine in a mice hepatic-fibrosis model. RESULTS: A high titer of anti-TGFbeta1 antibody and a low of anti-HBc antibody were detected in the mice after the immunization. The serum antibodies induced combined with the fusion and antigenic peptide prevented the TGFbeta1 inhibiting activity in the Mv-1-Lu cell. CONCLUSION: Recombinant fusion protein can be used as a cytokine vaccine to induce high titers of anti-TGFbeta1 antibodies. Our results show the potentiality of the fusion protein to be used as a vaccine for preventing liver fibrosis.