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Objective To prepare novel alkanethiol modified magnetic silver flower nanoparticles as SERS substrate to chloramphenicol for Raman detection and to determine their enhancement effect.Methods An alkanethiol was chosen as a surface modifier of the substrate and was self-assembled onto the magnetic silver flower nanoparticle surface.The chloram-phenicol molecules were enriched to the surface of the substrate by hydrophobic interaction and the effect for detection of chloramphenicol SERS signal was enhanced.Results It was found that the 1-hexanethiol-modified SERS substrate was able to lead to stronger enhancement than 1-dodecanethiol and octadecanethiol.Fe3 O4@SiO2-Ag-C6 was used to detect the chloramphenicol (10 -3 -10 -10 mol/L) and chloramphenicol in milk (10 -3 -10 -9 mol/L) by surface-enhanced Raman spectroscopy.The detection limits were 0.1 nmol/L (32 ppt) and 1 nmol/L (323 ppt) respectively.Conclusion Alkanethiol modified magnetic silver flower nanoparticles are a highly active SERS substrate, which can be used for detection of low concentrations of analytical substances.
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A new medical research technology that combines surface enhanced Raman spectroscopy (SERS)with labeling immune technique is emerging with the development of SERS.This paper is intended to describe the principles, research progress and existing problems relating to SERS labeling immunoassay technology.We also summarize the research techniques for improving the sensitivity of SERS labeling immunoassay and the methods to eliminate nonspecific adsorption in SERS labeling immunoassay.Furthermore,the future development of SERS labeling immunoassay technology is discussed.
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Objective To develop a new type of Raman-enhanced substrate for rapid detection of E.coli based on label-free surface-enhanced Raman scattering( SERS) technology.Methods Stober’ s improved method was used to prepare 360 nm silica ( SiO2 ) nanospheres.Prepared gold core-silver shell nanoparticles( Au@Ag) of different size were attached to 360 nm SiO2 to fabricate the nanocomposites ( SiO2-Au@Ag ) that were characterized by transmission electron microscopy (TEM) and UV-visucl light adsorption spectra (UV-Vis).PATP was detected to select SiO2-Au@Ag with optimal SERS effect.This optimal SiO2-Au@Ag was used to obtain the sensitivity of PATP and E.coli detection after a simple mixed culti-vation.Results TEM images showed that Au@Ag aggregated with the size of Au@Ag attached to 360 nm SiO2 .UV-Vis spectra indicated that the maximum absorption of Au@Ag and SiO2-Au@Ag had a red shift with the invrease of Au@Ag size.The experiment results suggested that detection sensitivity of PATP by SiO2-100 nm Au@Ag 10 -10 mol/L, while the lowest detectable E.coli concentration was 105 CFU/ml.Conclusion The 360 nm SiO2 binding with 100nm Au@Ag exhibits great potential for SERS applications.
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Objective To investigate the effect of Helicobacter pylori (H. pylori) eradication on reversing gastric antrum atrophy and intestinal metaplasia (IM). Methods Biopsy specimens obtained from gastric antrum of patients who underwent gastroscopy were examined for pathology and the status of H. pylori infection. The H. pylori infected patients who had chronic gastritis with antrum atrophy or IM were recruited and were divided into either H. pylori eradicated group (n= 48)or control (non-eradicated) group (n=38). The gastroscopic follow-up was carried out at 1 year and 5years. The specimens examined for changes of histology and reverse of gastric antrum and IM were obtained at the same site. Results The reversing rate of gastric antrum atrophy in H. pylori eradicated group was significantly higher than that in control group (37.1% vs. 12.0%). In H. pylori eradicated group, the reversing rate of gastric antrum atrophy at 5-year was significantly higher than that at 1-year, and it was higher in patients aged below 45 years than those aged above 45 years.Whereas there was no association of reversing gastric antrum atrophy with follow-up time and age in control group. However there was no difference in reversing rate of IM between two groups in 1- or 5-year follow-up and H. pylori eradication. Conclusions H. pylori eradication can not reverse the IM of gastric antrum mucosa, but it can reverse the atrophy of gastric mucosa, which is associated with follow-up time and the age of patients. Therefore, H. pylori must he eradicated as early as possible in H. pylori infected patients with gastric antrum atrophy.
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Objective To investigate the difference of clinical features between primary colorectal malignant T cell lymphoma and primary colorectal malignant B cell lymphoma.Methods Forty cases diagnosed as primary eolorectal malignant lymphoma (PCML) between Jan 1999 and May 2008 were studied retrospectively.Results The average age of 40 patients with PCML was (41.0±11.2) years old.Twenty-seven cases (67.5%) were diagnosed as B-cell lymphoma.Thirteen cases (32.5%) were diagnosed as T-cell lymphoma.Patients with T-cell lymphoma in PCML had more symptoms such as fever,night sweat and hematochezia,and was easier to perforate than those with B-cell lymphoma.Protrude type and single-focus and right-colon type were common in B-cell lymphoma under colonoscopy,but ulcerative type and multi-focus and fulbcolon were common in T-cell lymphoma.B-cell lymphoma had an earlier diagnosis,and more opportunities for surgery than T-cell lymphoma.Conclusions The misdiagnostic rate for PCML was high.Protrude type and single-focus and right-colon type were common in B-cell lymphoma under eolonoscopy,but ulcerative type and multi-focus and full-colon were common in T-cell lymphoma.B-cell lymphoma could be diagnosed earlier.
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Objectives To investigate the clinical characteristics and the regularity of seasonal changes that influence peptic ulcer (PU) in Nanehang area and to provide a theoretical basis for the treatment and prevention of PU.Methods Data collected from patients with PU diagnosed by clinic and gastroendoseopy between October 2003 to May 2008 were retrospectively analyzed.The PU was further divided into gastric ulcer,duodenal ulcer and complex ulcer.The lesion of gastric ulcer was calculated by five locations that were antral,angular,corporal,pyloric canal,fundic and cardia.The lesion of duodenal ulcer was calculated by five locations that were anterior wall of bulb,posterior wall,lesser curvature, greater curvature and postbulbar.The climate changes that influnced the incidence of PU disease were also observed.The detective rates of different types of PU were analyzed and its association with gender,age, lesion locations,seasons,Helicobacter pylori (Hp) infection and complications were also investigated. Results Among 83 888 patients who underwent endoscopy,PU was found in 21 308 patients (25.4%) including 66.33% duodenal ulcer,24.88% gastric ulcer and 8.79% complex ulcer.The male and femal ratio was 2.44 : 1 in PU,2.53 : 1 in duodenal ulcer,2.26 : 1 in gastric ulcer,and 2.33 : 1 in complex ulcer.The average age of patients with gastric ulcer was 48.0 years that was about 6.7 years higher than that of patients with duodenal ulcer.The prevalence of duodenal ulcer and gastric ulcer peaked in the 30- 39 years and 50-59 years,respectively.PU was more common from December to February (30.17%) and less common from June to August (22.54%) (P＜0.01) .The 57.43% of duodenal ulcer was found on anterior wall of bulb,18.26% on greater curvature,13.21% on lesser curvature,7.34% on posterior wall and 3.76% on postbulbar.The 45.69% of gastric ulcer was found on antral,20.54% on angular, 15.54% on corporal,9.36% on pyloric canal,and 8.87% on fundic and cardia.The 91.83% (12 318/ 13 414) of patients were positive for Hp infection.There was no significant difference of Hp infection among patients with different types of PU.The complications in patients with PU were bleeding (4.94%),pyloric obstruction (3.51%) and chronic perforation(0.04%).Conclusions The detective rate of PU in Nanchang area is 25.4%,which is higher than that in northern area of China.The incidence of PU is highly associated with sex,age,seasons and ulcer locations,with high Hp infections and a low incidence of complications.
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Objective To study the relationship between endoscopic and histologic mucosal changes in chronic gastritis.Methods All 403 patients with chronic gastritis were examined by endoscopy and two samples of gastric mucosa were examined by the same pathologist.Results (1)Gastroscopic results:there were 380 cases of chronic superficial gastritis(CSG),38 cases of chronic atrophic gastritis(CAG) including 15 cases of coexistence of CSG and CAG.(2)Pathologic results:365 cases of CSG;49 cases of CAG including 11 cases of coexistence of CSG and CAG.Among 403 cases,108 cases with intestinal metaplasia(IM),59 cases with mucosal erosion.39 cases had active chronic gastritis(ACG).(3)For CSG,comparing with pathology,endoscopic results had 95.3% of sensitivity and 91.6% of positive predictive value.In contrast their specific rate and negative predictive value were 15.8% and 26.6%,respectively;for CAG,endoscopy had 96.0% of specific rate and 93.2% of negative predictive value for pathologic diagnosis.Its sensitivity and positive predictive value were 46.2% and 63.2% respectively.(4)Comparing with pathologic results,endoscopic features had less sensitivity(50%),but some had a higher positive predictive value for pathologic CSG,CAG,and IM.(5)CAG was most likely associated with type Ⅱ IM(85.2%).Although most type Ⅰ IM was presented in CSG(81.0%).Conclusion Any single endoscopic finding was nonspecific for pathologic diagnosis;although some charactristical endoscopic findings had a higher positive predictive value. In other words,a single pathologic change may associated with various endoscopic findings, while a single later finding only presented one or two pathologic changes.
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Patients with irritable bowel syndrome(IBS,n=41)subjected to gastroscopy,patholo- gy,esophageal manometry and 24h pH monitoring.The records were compared with that of normal in- dividuals(n=30)to clarify the relation of esophageal motor function with esophageal complaints in cas- es with IBS.Results showed that 21/41 cases with IBS presented esophageal symptoms.Rate of abnor- mal endoscopic and pathologic findings in 6 of which was statistically higher than the control's; esophageal lower sphincter pressure in IBS with symptoms declined significantly than that without and the control;esophageal peristaltic velocity and duration increased with significance;no pressure differ- ence was detected in esophageal upper sphincter;total pH score ,fraction-time pH
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The Helicobacler pylori and ABO blood group of 217 patients and 169 blood donorswere identified by bacteriologic and serologic method,Aiming to expore the relation between H. pylori infection and ABO blood group. The result show: (1) Among patients with peptic ulcer there were a increase in the proportion of blood group O; (2) The infection rate of H.pylori in the proportion of bloodgroup O was significatly higher than in those not blood group O (P