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1.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-969621

RESUMEN

Pancreatic cancer is a disease with a high fatality rate, with a five-year survival rate of no more than 10% and a significantly increasing annual mortality rate. The common pathogenesis factors of pancreatic cancer are family inheritance, diet, pancreatitis, obesity, etc., among which, family inheritance of pancreatic cancer is the main reason, and about 7%-10% of patients have family inheritance. Surgery is an effective way to treat pancreatic cancer in patients and improve their survival, but most people are diagnosed with pancreatic cancer at intermediate and advanced stages and lose the opportunity for surgical treatment. Therefore, radiotherapy, interventional therapy, supportive treatment, immunotherapy, and other treatments are used clinically to relieve symptoms and prolong the survival of patients. The commonly used clinical drug is gemcitabine. Although it can inhibit tumor growth and improve the condition, it can bring side effects such as bone marrow suppression, rash, digestive tract side effects, and drug resistance. The damage of these side effects to the human body is systemic. Chinese medicine can be used alone or in combination with other treatment methods to reduce the toxic and side effects of chemotherapy, restore the physical energy of patients, and reduce its related complications. Chinese medicine contains a large number of active ingredients, including alkaloids, flavonoids, saponins, phenolic acids, and organic acids, with anti-inflammatory, anti-viral, anti-tumor, and other curative effects. Many clinical studies of traditional Chinese medicine (TCM) on cancers have verified that TCM plays a positive role in tumor prevention and treatment, especially in improving and controlling clinical symptoms, and also plays a good detoxification effect on radiotherapy and chemotherapy, with good results achieved in improving bone marrow suppression, improving immunity, improving quality of life, and prolonging survival. This paper reviewed the anti-pancreatic cancer mechanism of Chinese medicine monomers based on literature in China and abroad, aiming to provide new potential drug candidates for the treatment of pancreatic cancer.

2.
Front Public Health ; 10: 1025271, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36419999

RESUMEN

Background: The purpose of this study is to develop an artificial intelligence (AI)-based automated diabetic retinopathy (DR) grading and training system from a real-world diabetic dataset of China, and in particular, to investigate its effectiveness as a learning tool of DR manual grading for medical students. Methods: We developed an automated DR grading and training system equipped with an AI-driven diagnosis algorithm to highlight highly prognostic related regions in the input image. Less experienced prospective physicians received pre- and post-training tests by the AI diagnosis platform. Then, changes in the diagnostic accuracy of the participants were evaluated. Results: We randomly selected 8,063 cases diagnosed with DR and 7,925 with non-DR fundus images from type 2 diabetes patients. The automated DR grading system we developed achieved accuracy, sensitivity/specificity, and AUC values of 0.965, 0.965/0.966, and 0.980 for moderate or worse DR (95 percent CI: 0.976-0.984). When the graders received assistance from the output of the AI system, the metrics were enhanced in varying degrees. The automated DR grading system helped to improve the accuracy of human graders, i.e., junior residents and medical students, from 0.947 and 0.915 to 0.978 and 0.954, respectively. Conclusion: The AI-based systemdemonstrated high diagnostic accuracy for the detection of DR on fundus images from real-world diabetics, and could be utilized as a training aid system for trainees lacking formal instruction on DR management.


Asunto(s)
Diabetes Mellitus Tipo 2 , Retinopatía Diabética , Humanos , Retinopatía Diabética/diagnóstico , Inteligencia Artificial , Diabetes Mellitus Tipo 2/diagnóstico , Estudios Prospectivos , Sensibilidad y Especificidad
3.
Chinese Journal of Radiology ; (12): 568-572, 2020.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-868315

RESUMEN

Objective:To explore the value of X-ray signs with applying low dose of contrast agent to confirm successful puncture in direct shoulder MR arthrography.Methods:In total 669 patients who underwent shoulder MR arthrography in Peking University Third Hospital from January 2016 to August 2018 were retrospectively analyzed. All patients received the anterior approach puncture in shoulder arthrography. X-ray films were taken after 1-2 ml contrast agent was injected. Six X-ray signs of contrast agent distribution were recorded. MR arthrography findings were used to confirm whether the puncture was success. Kappa analysis was used to verify the consistency between each 2 signs. The accuracy rate of each X-ray sign to confirm the successful puncture was calculated. X-ray signs were paired to define the best diagnostic index of successful puncture.Results:Successful puncture was performed in arthrographies for all 669 cases .The displaying rates of six signs were as follows. Contrast agent distribution at overlapping humeral head away from the needle was 66.8% (447/669), in axillary recess was 64.7% (433/669), in glenohumeral space was 93.9% (628/669), in subscapular bursa was 69.8% (467/669), in sheath of long head tendon of biceps brachii (LHBT) was 1.9% (13/669), between LHBT and supraspinatus tendon was 17.2% (115/669). Consistency of each 2 signs was poor (Kappa<0.2), in which the poorest consistency was found between contrast agent overlapping humeral head away from the needle and contrast agent in glenohumeral space (Kappa=-0.115). With combining the above 2 signs, the accuracy rate for defining successful puncture was 100% (669/669).Conclusion:In direct shoulder arthrography by anterior approach, X-ray signs with low dose of contrast agent can be regard as the method to confirm successful puncture. The accuracy rate of the signs of contrast agent distribution at overlapping humeral head away from the needle or in glenohumeral space to define a successful puncture is 100%.

4.
Spectrochim Acta A Mol Biomol Spectrosc ; 191: 442-453, 2018 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-29078138

RESUMEN

The following paper reported and discussed a nitrite ion optical sensing platform based on a core-shell structure, using superamagnetic nanoparticles as the core, a silica molecular sieve MCM-41 as the shell and two rhodamine derivatives as probe, respectively. This superamagnetic core made this sensing platform reclaimable after finishing nitrite ion sensing procedure. This sensing platform was carefully characterized by means of electron microscopy images, porous structure analysis, magnetic response, IR spectra and thermal stability analysis. Detailed analysis suggested that the emission of these composite samples was quenchable by nitrite ion, showing emission turn off effect. A static sensing mechanism based on an additive reaction between chemosensors and nitrite ion was proposed. These composite samples followed Demas quenching equation against different nitrite ion concentrations. Limit of detection value was obtained as low as 0.4µM. It was found that, after being quenched by nitrite ion, these composite samples could be reclaimed and recovered by sulphamic acid, confirming their recyclability.

5.
Spectrochim Acta A Mol Biomol Spectrosc ; 191: 134-142, 2018 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-29028505

RESUMEN

Optical sensing for cysteine (Cys) recognition is an interesting topic due to Cys biological participation. In this paper, two rhodamine-based chemosensors were designed for Cys optical sensing. For chemosensor photostability improvement, up-conversion nanocrystals were synthesized and used as excitation host. These nanocrystals were modified with a phase transfer reagent α-cyclodextrin (α-CD) to improve their compatibility with chemosensors. An efficient energy transfer from these nanocrystals to chemosensors under 980nm radiation was observed and confirmed by spectral match analysis, energy transfer radius calculation and emission decay lifetime comparison. A direct bonding mechanism between Cys and chemosensors with bonding stoichiometry of 1:1 was established by Job's plot experiment. Given the presence of Cys, chemosensor emission was increased, showing emission turn on effect. These two chemosensors showed good selectivity, improved photostability and linear sensing response towards Cys.


Asunto(s)
Cisteína/análisis , Colorantes Fluorescentes/química , Nanocompuestos/química , Rodaminas/química , Transferencia de Energía , Colorantes Fluorescentes/síntesis química , Luz , Nanocompuestos/ultraestructura , Nanopartículas/química , Nanopartículas/ultraestructura , Espectrometría de Fluorescencia , Espectrofotometría Infrarroja , Difracción de Rayos X
6.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-687589

RESUMEN

The accurate position of the center of rotation (COR) is a key factor to ensure the quality of computed tomography (CT) reconstructed images. The classic cross-correlation matching algorithm can not satisfy the requirements of high-quality CT imaging when the projection angle is 0 and 180°, and thus needs to be improved and innovated. In this study, considering the symmetric characteristic of the 0° and flipped 180° projection data in sinogram, a novel COR correction algorithm based on the translation and match of the 0° and 180° projection data was proposed. The OTSU method was applied to reduce noise on the background, and the minimum offset of COR was quantified using the -norm, and then a precise COR was obtained for the image correction and reconstruction. The Sheep-Logan simulation model with random gradients and Gaussian noise and the real male SD rats samples which contained the heterogenous tooth image and the homogenous liver image, were adopted to verify the performance of the new algorithm and the cross-correlation matching algorithm. The results show that the proposed algorithm has better robustness and higher accuracy of the correction (when the sampled data is from 10% to 50% of the full projection data, the COR value can still be measured accurately using the proposed algorithm) with less computational burden compared with the cross-correlation matching algorithm, and it is able to significantly improve the quality of the reconstructed images.

7.
China Occupational Medicine ; (6): 677-682, 2017.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-881988

RESUMEN

OBJECTIVE: To establish a PC12 cell line with stable expression of human apolipoprotein E( ApoE4) gene by transfection with a lentiviral vector carrying human ApoE4 gene and to investigate the effect of maltol aluminum on the viability of transfected PC12 cells. METHODS: The lentiviral vector carrying human ApoE4 gene was transfected into PC12 cells. PC12 cells with overexpression of ApoE4 gene and negative control vector were obtained after puromycin screening.The mRNA relative expression of R-Apo E and( or) H-Apo E-FLAG of cells in PC12,PC12-NC and PC12-ApoE4 groups were detected by real-time fluorescent quantitative polymerase chain reaction,and the effect of cell construction was identified. PC12-ApoE4 cells and PC12 cells were exposed to maltol aluminum solution at concentrations of 0. 00,100. 00,200. 00 and 400. 00 μmol/L respectively for 24 hours,and cell viability was detected by Cell Counting Kit-8( CCK-8)assay. RESULTS: PC12-ApoE4 and PC12-NC cells under the fluorescence microscope showed fluorescence expression,suggesting that transfection was successful. The expression of PC12 cells showed no fluorescence. The relative expression of H-Apo E-FLAG gene mRNA( the median amount) of PC12-ApoE4 cells was 148. 74,which was higher than the R-Apo E gene in PC12 cells( 1. 00) and PC12-NC cells( 1. 01)( P < 0. 01). After exposure to maltol aluminum,the cell survival rates in terms of the main effect and interaction effect of dose and cell type were statistically significant( P < 0. 01),among them,the cell viabilities were decreased in the concentration range of 0. 00-400. 00 μmol/L with the dose of maltol aluminum exposure increased,showing dose-effect relationship( P < 0. 01). CONCLUSION: The cell line stably expressed human ApoE4 gene was constructed successfully. There was interaction between the effects of maltol aluminum and ApoE4 gene on the survival rate of PC12 cells,and ApoE4 gene could enhance the cytotoxicity of maltol aluminum on PC12 cells.

8.
Artículo en Inglés | MEDLINE | ID: mdl-27323315

RESUMEN

In this report, a diamine ligand having an electron-pulling group in its conjugation plane was designed. A methyl group was connected with this diamine ligand, hoping to further increase its steric hindrance. Its Cu(I) complex was synthesized and characterized by NMR, single crystal analysis and photophysical analysis. There was a distorted tetrahedral coordination field in this Cu(I) complex. Its onset electronic transition owned a mixed character of metal-to-ligand-charge-transfer which suffered from bad geometric relaxation. To limit this geometric relaxation and improve emissive performance, this Cu(I) complex was doped into a polymer host through electrospinning technique. Photophysical comparison between solid state sample, solution sample and composite samples indicated that excited state geometric relaxation was effectively limited by polymer immobilization effect, resulting in improved emissive performance, such as emission blue shift, long emission decay lifetime and better photostability.

9.
Chinese Herbal Medicines ; (4): 70-73, 2012.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-499760

RESUMEN

ObjectiveTo optimize the extraction technology of the active component,rosmarinic acid,an ester of caffeic acid and 3,4-dihydroxyphenyllactic acid,in perilla oil meal for the first time by a new homogenizing technology called smashing tissue extraction (STE).MethodsOrthogonal design was used to optimize the extraction condition.The content of rosmarinic acid was quantified from the methanol crude extract with the help of HPLC.ResultsThe optimization of STE process to get rosmarinic acid from the perilla oil meal was the ratio of liquid to solid material at 10∶1 and the power of extraction at 150 V,extracting twice (2 min for each time).ConclusionSTE could be applied to extracting the active ingredients from the oil meals due to its high extraction efficiency.This new homogenizing technology has advantages on saving extraction time,raising extraction efficiency,and maintaining the temperature sensitive constituents.

10.
Chinese Herbal Medicines ; (4): 259-262, 2012.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-499742

RESUMEN

Objective To optimize the extract technology of active lignins from the fruits of Schisandra chinensis.Methods The content of schizandrin,gomisin A,and deoxyschizandrin were selected as standards to evaluate the efficiency of smashing tissue extraction (STE).Solid-liquid ratio,extracting times,ethanol concentration,and extracting time were investigated through orthogonal test.Results The optimized conditions for STE were ten times amount of 80% EtOH,extracting for three times,and 2 min for each time.Conclusion STE could obtain relatively higher yield,simplicity of operation,and benefit for environment protection.It could be better choice for the extraction ofS.chinensis.

11.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-289359

RESUMEN

<p><b>OBJECTIVE</b>To introduce the establishment of food pharmacy research progress.</p><p><b>METHOD</b>To overview research situations of food pharmacy development according to edible product.</p><p><b>RESULT</b>Food pharmacy development in China has been set up preliminarily, and needs to be developed further.</p><p><b>CONCLUSION</b>The trend of the functional food will be safe, effective and its quality will be control.</p>


Asunto(s)
Análisis de los Alimentos , Tecnología de Alimentos , Farmacia
12.
Chinese Herbal Medicines ; (4): 75-78, 2011.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-499834

RESUMEN

Objective To optimize the extraction technology of perilla seeds oil from the oil cake of perilla seeds (OCPS) by using the contents of active fatty acids as evaluation standard. Methods The fatty acids were extracted from OCPS,the residue of perilla seeds after cold-press, by smashing tissue extraction (STE), the new technology selected through comparing with classical leaching extraction (LE), Soxhlet extraction (SE), ultrasonic extraction (UE), and supercritical-CO2 fluid extraction (SFE). For optimized condition of STE, orthogonal test was designed and completed. The contents of five fatty acids in extracted oil and OCPS were determined by GC. Results The optimized extraction parameters were smashing for 1.5 min under extraction power of 150 W and 1:6 of the material/solvent ratio. The contents of five fatty acids in the oils extracted by five techniques from OCPS and determined by GC were as follows:a-linolenic acid (41.12%-51.81%), linoleic acid (15.38%-16.43%), oleic acid (18.93%-27.28010), stearic acid (2.56%-4.01%), and palmitic acid (7.38%-10.77%). Conclusion The results show that STE is the most efficient technology with the highest yield (LE:0.57%; SE:1.03%; UE:0.61%; SFE:0.8(r; STE:1.17%) and shortest time (LE:720 min; SE:360 min; UE:30 min; SFE:120 min; STE:1.5 min) among five tested extraction technologies. It is fast reported using STE to extract herbal oil enriched with active fatty acids.

13.
Chinese Herbal Medicines ; (4): 235-238, 2011.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-499802

RESUMEN

Objective To optimize the extraction technology of Taxus x media by using the contents of Paclitaxel and 10-deacetylbaccatin(10-DAB),two representative active diterpene alkaloids of taxane type from T.x media,as evaluation standard.Methods The smashing tissue extraction(STE)of Paclitaxel and 10-DAB from T.x media,was investigated by comparing with ultrasonic extraction(UE)which was one of the modern technologies of extraction.Results STE was more efficient than UE,and the contents of 10-DAI3 and Paclitaxel in the extracts obtained by STE were higher than those by UE.Conclusion STE is a fast,high-performance,and energy-saving technology for the extraction of diterpene alkaloids of taxane type.STE also provides a simple,component-safe,workable,and highly efficient method for the extraction of active natural product.

14.
Chinese Herbal Medicines ; (4): 232-234, 2011.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-499717

RESUMEN

Objective To find antitumor cOnstituents from Tripterygium hypoglaucum.Methods The chloroform extract of T.hypoglaucum was separated by silica gel column chromatography and preparative HPLC.The structures of compounds isolated were identified by spectral analysis and chemical evidence.Results Seven compounds were isolated and identified as rhein ethyl ester(1),chrysophenol(2),physcion(3),emodin(4),wilfordine(5),wilforgine(6),and wilforine(7).The cytotoxic activities of the compounds against cancer cell lines were assayed.Conclusion Compound 1 is a new natural compound with strong activities against human cancer cell lines (A2780 and OVCAR-3).Compounds 2-4 are isolated from this genus plants for the first time.The possible structure-activity relationship among compounds 1-4 shows that the methoxy group or oxyethyl moiety might be responsible for the cytotoxity.

15.
Chinese Herbal Medicines ; (4): 150-155, 2011.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-499704

RESUMEN

Objective Ginger (Zingiber officinale) is widely used as a spice in cooking and as a medicinal herb in traditional herbal medicine. The present study was to investigate the analgesic and anti-inflammatory activities of ginger oil in experimental animal models. Methods The analgesic effect of the oils was evaluated by the acetic acid and hot-plate test models of pain in mice. The anti-inflammatory effect of the oil was investigated in rats, using rat paw edema induced by carrageenan, adjuvant arthritis, and vascular permeability induced by bradykinin, arachidonic acid, and histamine. Indomethacin (1 mg/kg), Aspirin (0.5 g/kg) and Dexamethasone (2.5 mg/kg) were used respectively as reference drugs for comparison. Results The ginger oil (0.25-1.0 g/kg) produced significant analgesic effect against chemically- and thermally-induced nociceptive pain stimuli in mice (P < 0.05, 0.01). And the ginger oil (0.25-1.0 g/kg) also significantly inhibited carrageenan-induced paw edema, adjuvant arthritis, and inflammatory mediators-induced vascular permeability in rats (P < 0.05, 0.001). Conclusion These findings confirm that the ginger oil can be used to treat pain and chronic inflammation such as rheumatic arthritis.

16.
Chinese Herbal Medicines ; (4): 317-320, 2010.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-499777

RESUMEN

Objective To study the triterpene saponins from Gynostemma pentaphyllum with antitumor activities.Methods The 75% EtOH extract of G.pentaphyllum was used for isolation by silica gel column chromatography and preparative HPLC.The structures of pure compounds isolated were identified by the spectral analysis and chemical evidence.Results Two compounds were isolated and identified as 23(S)-3β,20ξ,21ξ-trihydroxy-19-oxo-21,23-epoxydammar-24-ene 3-O-α-L-rhanmopyranosyl(1→2)-[β-D-xylopyranosyl(1→β)]-β-D-arabinopyranoside(1)and23(S)-21(R)-O-n-butyl-3β,20ξ-dihydroxy-21,23-epoxydammar-24-ene 3-O-α-L-rhamnopyranosyl(1→2)-[β-D-xylo-pyranosyl(1→3)]-β-D-arabinopyrannside(2).Conclusion Compound 2 is a new triterpene saponin with moderate antitumor activities against the HL-60,Colon205,and Du145 cell lines.

17.
Chinese Herbal Medicines ; (4): 41-47, 2010.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-499728

RESUMEN

Objective To prepare an active anti-tumor component, compound K (C-K), from saponins in leaves of Panax notoginseng (SLPN) using immobilized β-glucanase. Methods Two entrapments, alginate gel-1 (Alg 1) and alginate gel-2 (Alg 2), were evaluated for their ability to immobilize β-glucanase. The amount and purity of C-K obtained from the transformation process were analyzed by HPLC, and the immobilizing parameters were optimized. Results β-Glucanase can be immobilized and reused with either of the entrapment. However, using AIg 1 resulted in higher enzyme activity than Alg 2. The optimal concentration of the immobilized enzyme was 10%; The optimal crosslinking time was 4-6 h; and the optimal concentration of the crosslinking agent was 6%-7%. Conclusion Immobilized β-glucanase shows sustained enzyme activity, good ethanol tolerance, and was reusable for the preparation of C-K from SLPN.

18.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-281753

RESUMEN

<p><b>OBJECTIVE</b>To develop an HPLC for determination of aglycone of momordicoside L in Momordica charantia.</p><p><b>METHOD</b>A Kromasil C18 (4.6 mm x 150 mm, 5 microm) column was used. The mobile phase was acetonitrile-H2O (64:36), the flow rate was 1.0 mL x min(-1) and the UV detection wavelength was set 203 nm.</p><p><b>RESULT</b>The calibration curves were linear from of 0.025 microg to 1 microg (r =0.9911), the contents of aglycone of momordicoside L in Shandong, Henan, Hebei, Jiangxi are 0.211, 0.033, 0.013, 0.007 mg x g(-1), respectively.</p><p><b>CONCLUSION</b>The method is simple and reliable for determination of aglycone of momordicoside L in M. charantia.</p>


Asunto(s)
Calibración , Cromatografía Líquida de Alta Presión , Métodos , Momordica charantia , Química , Saponinas
19.
Chinese Journal of Digestion ; (12): 217-220, 2008.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-383733

RESUMEN

Objective To investigate the potential mechanism of interleukin-1β(IL-1β)in H.pylori-related gastric carcinogenesis.Methods Human gastric cancer cell line(AGS),human gastric epithelial cell line(GES-1)and isolated parietal cells were treated with exogenous IL-1β(10 ng/ml)in the presence or absence of H.pylori(NCTC 11637).Cell proliferation and apoptosis were determined by MTT assay and flow cytometry,respectively. Expressions of cyclooxygenase-2(COX-2)mRNA and protein were examined using RT-PCR and flow cytometry,respectively.Acid secretion by parietal cells was tested using 14C-aminopyrine(14 C-AP) accumulation indirectly.H+/K+ ATPase α subunit mRNA expression was assessed using RT-PCR.Results The cell proliferation and H.pylori-related apoptosis in both GES-1 and AGS celL lines were stimulated and inhibited by IL-1β.IL-1β induced expression and upregulation of COX-2 mRNA in GES-1 and AGS cell lines,respectively.In addition,IL-1β continuously inhibited the ability of histamine-stimulated 14C-AP accumulation of isolated parietal cells accompanied by down-regulation of H+/K+ ATPase mRNA expression.Conclusions It suggests that IL-1β play an important role in H.pylori-related gastric carcinogenesis through two pathways:①to interfere gastric epithelial cell growth by up-regulating COX-2 expression,②to inhibit acid secretion from parietal cell by down-regulating H+/K+ ATPase expression.

20.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-399984

RESUMEN

Objective To explore the effects of H.pylori and crude extracted proteins secreted by H.pylori(broth culture filtrate protein,BCF-P)on acid secretion from isolated rabbit parietal cells.Methods Parietal cells from rabbit gastric mucosa were isolated and enriched with digestion and elutriation.H.pylori(NCTC 11637,CagA+ VacA+)were grown in liquid broth culture and BCF-P was precipitated with ammonium sulfate.The vacuolation activity of BCF-P was evaluated with neutral red dye uptake test in HeLa cell.Isolated parietal cells were incubated with H.pylori(bacteria/cell=100∶1)for 2 h and 16 h,or BCF-P(100μg/ml)for 1 h and 12 h.Acid secretion from parietal cells was studied using 14C-aminopyrine(14C-AP)accumulation indirectly and H+-K+ ATPase α subunit mRNA expression was assessed using RT-PCR.Results (1)BCF-P containing vacuolating cytotoxin(VacA)with vacuolation activity on HeLa cells had positive result on neutral red uptake test.(2)The basal expression of H+-K+ ATPase α subunit mRNA could be detected in isolated parietal cells and 14C-AP accumulation was significantly increased in response to the stimulation of histamine with different concentrations for 30 min(P<0.05).These results indicated that the isolated parietal cells retain relative intact acid secretion function.(3)The histamine(1.0×104 mol/L)stimulated acid secretion was inhibited sustainedly in response to H.pylori by 81% at 2 h and by 94% at 16 h(P<0.05).However,H+-K+ ATPase α subunit mRNA expression was up-regulated in tlle acute period(2 h)and was down-regulated in the chronic period (16 h)by H.pylori(P<0.05).(4)BCF-P significantly inhibited the histamine-stimulated acid secretion by 24% at 1 h and by 58% at 12 h(P<0.05),and this inhibition was accompanied by the down-regulated expression of H+-K+ATPase α subunit mRNA.Conclusions Intact H.pylori and VacA secreted by H.pylori could directly inhibit histamine-stimulated acid secretion from parietal cells and this inhibition may be mediated by the down-regulated H+-K+ ATPase expression.

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