Clinical value of oral contrast-enhanced ultrasonography in diagnosis of gastric tumors

BACKGROUND

The incidence of gastric cancer remains high, and it is the sixth most common cancer and the fourth leading cause of cancer deaths worldwide. Oral contrast-enhanced ultrasonography is a simple, non-invasive, and painless method for the diagnosis of gastric tumors.

AIM

To explore the diagnostic value of oral contrast-enhanced ultrasonography for the detection of gastric tumors.

METHODS

The screening results based on oral contrast-enhanced ultrasonography and electronic gastroscopy were compared with those of the postoperative pathological examination.

RESULTS

Among 42 patients with gastric tumors enrolled in the study, the diagnostic accordance rate was 95.2% for oral contrast-enhanced ultrasonography (n = 40) and 90.5% for electronic gastroscopy (n = 38) compared with postoperative pathological examination. The Kappa value of consistency test with pathological findings was 0.812 for oral contrast-enhanced ultrasonography and 0.718 for electronic gastroscopy, and there was no significant difference between them (P = 0.397). For the TNM staging of gastric tumors, the accuracy rate of oral contrast-enhanced ultrasonography was 81.9% for the overall T staging and 50%, 77.8%, 100%, and 100% for T1, T2, T3, and T4 staging, respectively. The sensitivity and specificity were both 100% for stages T3 and T4. The diagnostic accuracy rate of oral contrast-enhanced ultrasonography was 93.8%, 80%, 100%, and 100% for stages N0, N1-N3, M0, and M1, respectively.

CONCLUSION

The accordance rate of qualitative diagnosis by oral contrast-enhanced ultrasonography is comparable to that of gastroscopy, and it could be used as the preferred method for the early screening of gastric tumors.

Research status and prospect on the mechanisms of acupuncture and moxibustion treatment for constipation of Parkinson's disease

Constipation may accelerate the progression of Parkinson's disease (PD). The quality of life in PD patients can be significantly improved when constipation is treated, hence the disease progression may be delayed. At present, the mechanism research is still at the initial stage for acupuncture in treatment of PD, focusing on neurohumoral factors, intestinal flora, bacterial fermentation products and intestinal inflammation； and there are the problems such as single intervention, thinking limitation and insufficient cooperation among disciplines. This paper systematically reviews the mechanism research progress of acupuncture for the treatment of constipation in PD so as to provide the references for the subsequent studies.

Kinesin-14 KIFC1 promotes acrosome formation and chromatin maturation during mouse spermiogenesis

KIFC1, a member of kinesin-14 subfamily motors, is essential for meiotic cell division and acrosome formation during spermatogenesis. However, the functions of KIFC1 in the formation and maintenance of the acrosome in male germ cells remain to be elucidated. In this study, we report the structural deformities of acrosomes in the in vivo KIFC1 inhibition mouse models. The proacrosomal vesicles diffuse into the cytoplasm and form atypical acrosomal granules. This phenotype is consistent with globozoospermia patients and probably results from the failure of the Golgi-derived vesicle trafficking and actin filament organization. Moreover, the multinucleated and undifferentiated spermatogenic cells in the epidydimal lumen after KIFC1 inhibition reveal the specific roles of KIFC1 in regulating post-meiotic maturation. Overall, our results uncover KIFC1 as an essential regulator in the trafficking, fusion and maturation of acrosomal vesicles during spermiogenesis.

From Polyalthia to Polyalthiopsis (Annonaceae): transfer of species enlarges a previously monotypic genus

The genus Polyalthiopsis Chaowasku (Annonaceae) was a poorly known monotypic genus from Vietnam that was recently segregated from the highly polyphyletic genus Polyalthia s.l. The sister clade relationship between Polyalthiopsis and Miliusa was not well established in previous study. The phylogenetic position of two Polyalthia spp. from China, P. chinensis S.K.Wu ex P.T.Li and P. verrucipes C.Y.Wu ex P.T.Li, remains unresolved and is shown here to be phylogenetically affiliated with Polyalthiopsis. Phylogenetic analyses of six chloroplast regions (matK, ndhF, psbA-trnH, rbcL, trnL-F and ycf1; ca.7.3 kb, 60 accessions) unambiguously placed Polyalthia chinensis and P. verrucipes in the same clade with Polyalthiopsis floribunda (PP = 1, MPBS = 97%); the entire clade is sister to Miliusa with weak to strong support (PP = 1, MPBS = 54%). Polyalthia chinensis and P. verrucipes share several diagnostic characters with Polyalthiopsis floribunda, including the raised midrib on the upper surface of the leaf in vivo, conspicuous foliar glands when dried, petiole with transverse striations when dried and axillary inflorescences. The two species differ from Polyalthiopsis floribunda in having fewer flowers per inflorescence, longer linear petals and two ovules per carpel. On the basis of the combined molecular phylogenetic and morphological data, we propose two new combinations, Polyalthiopsis chinensis (S.K.Wu ex P.T.Li) B.Xue & Y.H.Tan and Polyalthiopsis verrucipes (C.Y.Wu ex P.T.Li) B.Xue & Y.H.Tan. The protologue of Polyalthia verrucipes did not include a description of the flowers, which we provide here. An updated description for the genus Polyalthiopsis and a key to species in the genus Polyalthiopsis is also provided.

[Short-term efficacy evaluation of laparoscopic spleen-preserving splenic hilus lymphadenectomy and left epigastrium mesogastric excision for advanced proximal gastric cancer based on mesangial anatomy]

Objective: To investigate short-term efficacy of laparoscopic spleen-preserving splenic hilus lymphadenectomy and left epigastrium mesogastric excision for advanced proximal gastric cancer based on mesangial anatomy. Methods: A case series study was carried out. Case inclusion criteria: (1) patient was confirmed as gastric adenocarcinoma by gastroscopic biopsy before operation; (2) locally advanced gastric cancer was confirmed by abdominal CT before operation; (3) no distant metastases such as liver, lung, and posterior peritoneal lymph nodes, and no tumor directly invading the pancreas, spleen, liver, and colon were verified by superficial lymph node ultrasound, chest and abdominal CT before operation;(4) total gastrectomy or proximal gastrectomy plus D2 lymphadenectomy were performed, and R0 resection was confirmed by postoperative pathology. Exclusion criteria: (1) intraperitoneal dissemination or distant metastasis was found during laparoscopic exploration; (2) No.10 lymph nodes were significantly enlarged or fused into clusters; (3) pathological diagnostic data were incomplete. According to above criteria, the clinicopathological data of 36 patients who underwent laparoscopic spleen-preserving No.10 lymphadenectomy and left epigastrium mesogastric excision based on interspace anatomy for advanced proximal gastric cancer in The First Affiliated Hospital of Zhengzhou University from June 2017 to March 2018 were retrospectively collected and analyzed. The intraoperative conditions, postoperative recovery and complications of patients were analyzed. Results: In 36 patients, the mean age was (59.8±8.0) years, the mean BMI was (23.9±3.5) kg/m(2), and 8 cases (22.2%) received preoperative chemotherapy. All the patients underwent successfully the laparoscopic spleen-preserving splenic hilus lymphadenectomy and left epigastrium mesogastric excision. In the examination of postoperative resected specimens, it was found that the mesangial boundary of the upper and posterior part of the stomach was smooth, indicating the efficiency of complete mesangial resection. No case was converted to open operation. The mean time of lymph node dissection and mesangial resection was (34.2±11.4) minutes. The mean blood loss during operation was (44.8±21.3) ml. The mean number of lymph node dissection per patient was 45.6±17.6. The mean number of No. 11p+11d lymph node dissection was 3.1± 2.8 per patient, and 7 patients were pathologically positive with metastasis rate of 19.4% (7/36). The mean number of No.10 lymph node dissection was 2.9±2.5 per patient, and 2 patients were pathologically positive with metastasis rate of 5.6% (2/36). The time to postoperative flatus was (3.8±0.6) days, time to removal of nasogastric was (1.9±0.7) days, time to the first intake of fluid was (3.0±0.4) days, time to removal of drainage tube was (6.0±1.2) days. Postoperative mean hospital stay was (12.8±4.0) days. One case (2.7%) developed pulmonary embolism and 1 case (2.7%) developed gastroplegia after operation. The morbidity of postoperative complication was 5.6% (2/36). No operative site infection, postoperative bleeding and death within postoperative 30-day were observed. All the 36 patients were followed up and the median follow-up was 18 months (12-28 months). Seven patients died of tumor relapse and metastasis (3 cases died within postoperative 1 year) and another 1 case developed colonic cancer 17 months after operation. Conclusion: Laparoscopic spleen-preserving splenic hilus lymphadenectomy and left epigastrium mesogastric excision for advanced proximal gastric cancer based on mesangial anatomy is safe and feasible.

Socioeconomic and Environmental Determinants to Preterm Birth in Tibetan Women: An Analysis Based on the Hierarchically Conceptual Frame

BACKGROUND

Preterm birth is a common cause of death in newborns and may result from many determinants, but evidence for the socioeconomic and environmental determinants of preterm birth in Tibetan women of childbearing age is limited. The aim of this study was to understand the current status of preterm birth in native Tibetan women and investigate the socioeconomic and environmental determinants.

METHODS

Data were drawn from a cohort study which was conducted from August 2006 to August 2012 in rural Lhasa, Tibet, China. A total of 1419 Tibetan pregnant women were followed from 20 weeks' gestation until delivery; the loss to follow-up rate was 4.69%. The incidence of preterm birth was estimated to show the status of preterm births in Tibet. Logistic regression models for longitudinal data were established, and odds ratios (ORs) together with 95% confidence intervals (CIs) were used to evaluate the association between the occurrence of preterm birth and 16 selected potential determinants based on the hierarchical conceptual frame.

RESULTS

The incidence of preterm birth was 4.58% (95% CI = 3.55-5.80%). After adjusting for health-related variables of the mothers and newborns, socioeconomic and environmental determinants associated with preterm birth included season (spring: OR = 0.28, 95% CI = 0.09-0.84; autumn: OR = 0.21, 95% CI = 0.06-0.69; and winter: OR = 0.31, 95% CI = 0.12-0.82) and calendar year of delivery (2010: OR = 5.03, 95% CI = 1.24-20.35; 2009: OR = 6.62, 95% CI = 1.75-25.10; and 2007-2008: OR = 5.93, 95% CI = 1.47-23.90).

CONCLUSIONS

The incidence of preterm birth among native Tibetan women was low and there was a decreasing trend in recent years; however, it is still essential to strengthen seasonal maternal care, extend the spacing between pregnancies, and reinforce adequate maternal nutrition.

[PM2.5 and polluted gas exposure induced acute injury in rats'larynx membrane]

Objective:To study acute injury of rat's larynx membrane which were exposured to PM2.5 and polluted gas in serious air pollution. Method:Rats were divided into 3 groups of 5 animals each, the normal control group, gas exposured group, PM2.5 +gas exposured group. The control group served as the normal healthy control, rats of the gas exposured group had been exposured polluted gas in the A cabin, rats of PM2.5 +gas exposured group had been exposured PM2.5 and polluted gas in the B cabin. The total exposure time was six days. We collected specimen from 3 groups immediately after exposure. Histopathological changes in the rat's larynx membrane were assessed using hematoxylin and eosin staining(HE), the expression of IL-1β in laryngeal mucous membrane were assessed using immunohistochemical staining(IHC), and the ultrastructure changes were observed under TEM. Result:HE staining showed the rat's laryngeal mucosa cells in the normal control group had no obvious abnormalities, laryngeal mucosa of rats in the two experimental group had different degrees of cell proliferation, cell polarity change, etc. IHC staining showed that there's no obvious expression of IL-1β in laryngeal mucous membrane in the normal control group, and positive expression in the two experimental group. TEM showed the control group had no obvious abnormalities, the laryngeal mucosa cells in the two groups of experimental groups had been found irregular nucleus and damaged mitochondria. Conclusion:Exposed to PM2.5 and polluted gas in severe atmospheric pollution 6 days, the acute damage in rats laryngeal mucosa can be observed.

Maternal IgG Anti-A and Anti-B Titer Levels Screening in Predicting ABO Hemolytic Disease of the Newborn: A Meta-Analysis

Maternal IgG anti-A/B titers have been considered as a susceptible factor to the risk of ABO hemolytic disease in newborn (ABO-HDN). However, the results remain controversial. This meta-analysis aimed to estimate the association between maternal IgG anti-A/B titers and the risk of ABO-HDN.

METHODS

Trials on the relationship between maternal IgG anti-A/B titers and the risk of ABO-HDN were collected by searching Embase, PubMed, and Cochrane Central Register of Controlled Trials (CENTRAL) electronic databases. The inclusion criteria were maternal IgG anti-A/B titers screening and the evaluation of clinical outcomes in relation to ABO-HDN. Stata 12.0 was used to analyze the data.

RESULTS

A total of 23 trials were eligible for inclusion, of which four trials with 5,246 participants were suitable for this meta-analysis. Meta-analysis results suggested that maternal IgG anti-A/B titers were significantly associated with the risk of ABO-HDN [OR = 2.86, 95% CI = 2.50-3.28; OR = 4.67, 95% CI = 3.92-5.55; OR = 1.61, 95% CI = 1.36-1.91 in titers (128 to 256) vs. titers (64 or lower), titers (512 or higher) vs. titers (64 or lower), and titers (512 or higher) vs. titers (128-256), respectively].

CONCLUSIONS

Our meta-analysis suggests that maternal IgG anti-A/B titers are significantly associated with the risk of ABO-HDN. They contribute to the prediction of risk of ABO-HDN, in addition to the need for invasive treatment for antibody titers ≥512.

Expression of FK506-binding protein 52 (FKBP52) in chorionic villi with early recurrent spontaneous abortion

OBJECTIVE

To investigate the mRNA and protein expression of FK506-binding protein 52 (FKBP52) in the chorionic villi of patients with recurrent spontaneous abortion (RSA) and normal women during early pregnancy.

METHODS

Fresh chorionic villus tissues were collected from 60 subjects. A total of 30 patients with a history of RSA were enrolled into the RSA group and 30 normal pregnant women were enrolled into the control group. The FKBP52 mRNA expression levels in chorionic villi of the RSA patients and healthy controls were measured via semiquantitative RT-PCR. The protein distribution and expression levels of FKBP52 in chorionic villi were analyzed through immunohistochemistry (IHC). The correlation between FKBP52 expression and RSA was analyzed.

RESULTS

We demonstrated that FKBP52 mRNA is expressed in chorionic villi samples of normal pregnancy and RSA. RSA patients exhibited significantly lower FKBP52 gene expression levels compared with those in normal pregnancies (p < 0.05). FKBP52 immunoreactivity in chorionic villi was mainly observed in trophoblast cell cytoplasm. The FKBP52 protein expression levels in the chorionic villi of RSA patients was significantly lower than in normal women during pregnancy (p < 0.05).

CONCLUSIONS

FKBP52 protein levels were decreased in the chorionic villi of RSA patients, which indicate that the decrease in FKBP52 may be associated with RSA. The low FKBP52 mRNA expression level, which is consistent with the IHC result, may affect embryonic development and even lead to abortion. FKBP52 may be involved in the pathogenesis of RSA and new therapies that increase the FKBP52 expression may help treat RSA.

A serum proteomics approach to the diagnosis of ectopic pregnancy

An ectopic pregnancy (EP) occurs when implantation of the embryo occurs outside of the uterus. If left untreated, the developing fetus will continue to grow, leading to life-threatening consequences for the mother. A major difficulty with the diagnosis of ectopic pregnancy is that methods of detection are limited, and some, such as ultrasound, are not very reliable in the earliest days of gestation. Currently, no effective serum test exists to distinguish an ectopic pregnancy from a normal intrauterine pregnancy. The incidence of ectopic pregnancy is increasing and has doubled in the last 20 years. It is now the second most common cause of maternal death in the first trimester of pregnancy. To address this issue, we initiated a project to identify serum markers of ectopic pregnancy. The subjects for these studies presented at the Hospital of the University of Pennsylvania. We obtained over 140 serum samples from women with suspected ectopic pregnancy: women presenting with pain and/or bleeding in the first trimester of pregnancy. The approximate racial breakdown of the subjects is as follows: African American, 36%; Caucasian, 3%; Asian, 2%; Hispanic, 1%; unknown, 58%. Serum samples from 139 women (62 with ectopic pregnancy and 77 with a normal intrauterine pregnancy) were applied to WCX2 (weak ion exchange) protein chip surfaces and analyzed for serum markers using surface-enhanced laser desorption/ionization time-of-flight mass spectrometry (SELDI-TOF-MS). Several proteins in the 7500-18,000 Da mass range were identified that may discriminate an ectopic pregnancy from an intrauterine pregnancy. The most promising markers were analyzed using classification and regression tree analysis (CART) with and without clinical variables (serum hCG value, length of amenorrhea). Two different algorithms were developed that classify the patients on the basis of sensitivity (number of EPs who screen positive/# of EPs) or specificity (# of healthy patients who screen negative/# of healthy). Our current approach is to refine these two "rule sets" to segregate patients into three groups: those who need immediate intervention for a probable ectopic pregnancy, those who appear to have a normal pregnancy, and those who need further monitoring for diagnosis.

A new method for characterizing denitrifying phosphorus removal bacteria by using three different types of electron acceptors

This study investigated the characteristics of denitrifying phosphorus removal bacteria by using three different types of electron acceptors as well as the positive role of nitrite in phosphorus removal process. Denitrifying phosphorous removal bacteria was enriched under anaerobic-anoxic (A/A) condition. To understand A/A sludge better, sludge from two other sources were also studied. These include sludges obtained from a lab-scale anaerobic-anoxic-aerobic (A/A/O) system and a local sewage treatment plant. Three types of possible electron acceptors (oxygen, nitrate and nitrite) were examined for their roles in phosphorus uptake. The results obtained indicated that oxygen, nitrate and nitrite were able to act as electron acceptors successfully. This observation suggested that in addition to the two well-accepted groups of phosphorus removal bacteria (one can only utilize oxygen to take up phosphorus, P(O), while the other can use both oxygen and nitrate, P(ON)), a new group of phosphorus removal bacteria, P(ON(n)), which could use oxygen, nitrate or nitrite to take up phosphorus was identified. The relative population of these three types of bacteria could be calculated from results obtainable from phosphorus uptake batch experiments with either oxygen or nitrate or nitrite as electron acceptor. The results obtained in this study showed that A/A sludge had similar phosphorus removal performance as the A/A/O sludge. However, it has better denitrifying phosphorus removal capability, which was demonstrated by the relative population of the three groups of bacteria. The results also suggested that nitrite was not an inhibitor to phosphorus removal process. Instead, it is an alternative electron acceptor to oxygen or nitrate.

[The analysis of rice total RNA by capillary electrophoresis]

When the RNase was eliminated through backing at 200 degrees C or treated by diethylpyrocarbonate (DEPC), the total RNA of rice could be separated within 15 min using 1.0%T, 0%C linear polyacrylamide as sieving matrix and 7 mol/L urea as denaturant. The tRNA of rice can be separated into two classes and about nine peaks when high concentrated polyacrylamide sieving matrix (5.0%T, 0%C) was used. This technique could provide one of the rapid and accurate methods for the determination of RNA in plants.

[Determination of human PDGF-B promoter binding nuclear protein by capillary electrophoresis]

With the use of 1.0% T, 0% C linear polyacrylamide as sieving matrix, 0.25 x TBE(Tris 89 mmol/L, boric acid 89 mmol/L, EDTA 2 mmol/L) as running buffer and 15 degrees C as column temperature, the human PDGF-B promoter binding nuclear protein can be determined within 50 min with good resolution. The results proved that there are two proteins having strong ability binding human PDGF-B promoter, which similar to that in slab gel electrophoresis. This technique can provide one of the rapid and accurate separation methods in the studying of the formation and repression behavior of DNA binding protein based on PDGF gene as the target.

Molecular determinants of the caspase-promoting activity of Smac/DIABLO and its role in the death receptor pathway

Smac/DIABLO is a mitochondrial protein that is released along with cytochrome c during apoptosis and promotes cytochrome c-dependent caspase activation by neutralizing inhibitor of apoptosis proteins (IAPs). We provide evidence that Smac/DIABLO functions at the levels of both the Apaf-1-caspase-9 apoptosome and effector caspases. The N terminus of Smac/DIABLO is absolutely required for its ability to interact with the baculovirus IAP repeat (BIR3) of XIAP and to promote cytochrome c-dependent caspase activation. However, it is less critical for its ability to interact with BIR1/BIR2 of XIAP and to promote the activity of the effector caspases. Consistent with the ability of Smac/DIABLO to function at the level of the effector caspases, expression of a cytosolic Smac/DIABLO in Type II cells allowed TRAIL to bypass Bcl-xL inhibition of death receptor-induced apoptosis. Combined, these data suggest that Smac/DIABLO plays a critical role in neutralizing IAP inhibition of the effector caspases in the death receptor pathway of Type II cells.

Helicobacter pylori increases proliferation of gastric epithelial cells

The direct and indirect effects of helicobacter pylori on cell kinetics of gastric epithelial cell line AGS were investigated by flow cytometric analysis of Ki-67 positive cells and by MTT assay. Flow cytometric analysis of Ki-67 positivity permits detection of cells that are in S-phase, whereas the MTT assay is a colometric measure of the number of viable cells. In the absence of added stimulants, 23.06 (4.88)% mean (SD) of AGS cells were Ki-67 positive. When cells were preincubated in the presence of H pylori, there was a significant increase in Ki-67 positivity (66.20 (7.89)%, p < 0.001). This increase was not seen in cells cultured in the presence of Campylobacter jejuni (24.63 (8.11)% or Escherichia coli (21.66 (9.78)%). Pre-incubation of AGS cells with supernatants from both H pylori and mitogen activated peripheral blood lymphocytes also increased the per cent of cells that were Ki-67 positive (72.93 (8.68) and 69.96 (12.35)%; p, 0.001) respectively. Similar results were also found in MTT assay. These data show that both H pylori directly and the immune/inflammatory response to H pylori indirectly can influence the rate of epithelial cell proliferation, suggesting this bacterium may be an initiating step in gastric carcinogenesis and an important co-carcinogenic factor in H pylori positive subjects.

Enhanced T-helper 2 lymphocyte responses: immune mechanism of Helicobacter pylori infection

Several lines of evidence implicate Helicobacter pylori (H. pylori) infection in gastroduodenal inflammation. However, the exact pathogenesis of H. pylori infection is not fully understood. T-helper (TH) lymphocytes may be subdivided into TH1 and TH2 cells based on the distinct patterns of cytokine production. TH1 reaction is associated with immunity or resistance to infection, while TH2 reaction is associated with the progression or persistence of infection. The production of interferon-gamma (INF-gamma) and interleukin 2 (IL-2), which are type 1 cytokines, is decreased in H. pylori infection. Enhanced production of type 2 cytokines (IL-4) and IL-6) is observed in individuals with H. pylori infection. Suppressed proliferative responses of peripheral blood and gastric lymphocytes have also been demonstrated in patients with H. pylori colonisation, suggesting that specific T-cell responses may be down-regulated by an enhanced TH2 reaction. Suppressed TH1 and enhanced TH2 responses in H. pylori infection may be involved in the immunopathogenesis of chronic H. pylori infection.

Effect of IL-4 on peripheral blood lymphocyte proliferation: implication in immunopathogenesis of H. pylori infection

Interleukin (IL) 4 is a type 2 cytokine which has a negative immunoregulatory role in human infection. IL-4 suppresses the production of interferon-gamma and enhances IL-10 synthesis. However, the effect of IL-4 on proliferative response of lymphocytes remains to be elucidated. We have previously reported an increase in production of IL-4 in subjects with Helicobacter pylori (H. pylori) infection. To evaluate whether the increased IL-4 is responsible for the down-regulation of immune responses in H. pylori infection, we observed the proliferative response of peripheral blood lymphocytes (PBL) co-cultured with phythaemagglutinin (PHA) or H. pylori in the presence and absence of added IL-4. As we have previously shown, PHA and H. pylori may increase PBL proliferation (P < 0.001). An increase in PBL proliferation was observed when PBL were co-cultured with PHA (P < 0.001) or H. pylori (P < 0.001) in the presence of IL-4 compared to that in the absence of IL-4. The optimal dose of IL-4 to give maximal lymphocyte proliferation is 50 pg/ml for the PHA-stimulated group or 100 pg/ml for the H. pylori-stimulated group. The data suggest that the increased IL-4 does not directly contribute to suppressed lymphocyte proliferation in H. pylori infection. Further studies will be required to determine the role of IL-4 in other aspects of down-regulation of immune responses in H. pylori infection.

Up-regulation of CD44 and ICAM-1 expression on gastric epithelial cells by H. pylori

Interaction between lymphocytes and epithelial cells may play a key role in Helicobacter pylori (H. pylori)-associated gastric mucosal inflammation. This interaction process is at least partially mediated by various cell adhesion molecules. The aims of the present study were to assess using flow cytometric analysis whether H. pylori directly or supernatants from H. pylori-activated peripheral blood mononuclear cells (PBMC) can affect the expression of adhesion molecules on the gastric epithelial cell line AGS in vitro. The results showed that resting AGS cells expressed CD44 and ICAM-1. Co-culture of AGS with H. pylori or cytokine-rich supernatants from H. pylori-activated PBMC resulted in up-regulation of expression of CD44 and ICAM-1 on AGS cells. These data suggest that H. pylori directly and indirectly through inflammatory cytokines may contribute to alternations in adhesion molecule expression on gastric epithelial cells. This may be of pathological significance in H. pylori-associated gastric mucosal inflammation and carcinogenesis.

Helicobacter pylori-induced lipid peroxidation in peripheral blood lymphocytes

Several lines of evidence implicate Helicobacter pylori infection in the pathogenesis of gastritis and peptic ulceration. To investigate whether H. pylori can cause lipid peroxidation in lymphocytes in vitro and to look for experimental evidence of lipid peroxidation induced by H. pylori, the lipid peroxide (LPO) level in peripheral blood lymphocytes was measured using the thiobarbituric acid fluorescence method. In the absence of added H. pylori, the LPO level in lymphocytes was 0.133 +/- 0.033 nmol/10(6) cells, and in the co-culture of H. pylori with peripheral blood mononuclear cells 0.340 +/- 0.097 nmol/10(6) cells. A significant difference was found between the two groups (p < 0.001). Antioxidants, either superoxide dismutase or catalase, could inhibit LPO production in lymphocytes. The present data provide further evidence that H. pylori can induce lipid peroxidation, which may be responsible for the pathogenesis of H. pylori-associated mucosal damage.

Increased gastric production of interleukin-8 and tumour necrosis factor in patients with Helicobacter pylori infection

AIMS

To investigate the role of interleukin-8 (IL-8) and tumour necrosis factor (TNF) in patients infected with Helicobacter pylori.

METHODS

The study population comprised 52 patients with dyspepsia attending for upper gastrointestinal endoscopy. Of these patients, 35 were infected with H pylori. IL-8 and TNF concentrations in plasma, gastric juice, and gastric biopsy homogenate supernatant fluid were measured by radioimmunoassay and L929 cell bioassay, respectively.

RESULTS

The concentrations of IL-8 and TNF in gastric juice and gastric biopsy homogenates were substantially greater in patients infected with H pylori. In H pylori positive patients IL-8 concentrations in gastric juice and gastric biopsy homogenates were higher in those with moderate gastritis than in those with mild gastritis. There was a positive correlation between IL-8 and TNF concentrations in gastric juice and gastric biopsy homogenate supernatant fluid from H pylori positive patients. There were no significant differences between H pylori positive and negative patients with respect to IL-8 and TNF plasma concentrations.

CONCLUSION

This study suggests that increased gastric production of IL-8 and TNF may be implicated in the pathogenesis of H pylori associated gastroduodenal disease.

Gastric T lymphocyte responses to Helicobacter pylori in patients with H pylori colonisation

Helicobacter pylori has been identified as a dominant factor in the pathogenesis of duodenal ulcer. The aim of this study was to examine peripheral blood and gastric lymphocyte proliferation and cytokine production in patients with H pylori colonisation. Sixty five dyspeptic patients attending for endoscopy were studied; 35 of these were H pylori positive and 30 H pylori negative as assessed by culture, histology, and rapid urease test. H pylori antigen was capable of stimulating peripheral blood lymphocyte proliferative responses even in H pylori negative patients. Peripheral blood lymphocyte proliferative responses to H pylori (but not to purified protein derivative or phythaemagglutinin) were significantly lower in H pylori positive than H pylori negative patients. Similarly, antigen specific proliferative responses and interferon gamma production by gastric lamina propria lymphocytes were also depressed in H pylori positive patients compared with H pylori negative patients. CD8 and CD22 positive lamina propria lymphocytes were increased in H pylori positive patients. These data show that antigen specific responses to H pylori are significantly lower in H pylori positive patients and could indicate activation of antigen specific suppression.

Interferon-gamma and tumour necrosis factor production in patients with Helicobacter pylori infection

The production of the cytokines, interferon-gamma and tumour necrosis factor by human antral mucosa cells and stimulated peripheral blood mononuclear cells were determined by enzyme linked immunosorbent assay and L929 bioassay respectively. Tumour necrosis factor production by peripheral blood mononuclear cells in response to Helicobacter pylori stimulation was depressed in Helicobacter pylori positive individuals, compared to Helicobacter pylori negative individuals (P < 0.05). There was no difference in tumour necrosis factor production by peripheral blood mononuclear cells in response to purified protein derivative. However, tumour necrosis factor production by cells isolated from gastric mucosa during short term culture was significantly higher in Helicobacter pylori positive patients (P < 0.05) than negative patients, indicating a probable macrophage response. Levels of interferon-gamma did not differ significantly in the gastric explant culture from the two groups. The results show that Helicobacter pylori negative patients have a stronger peripheral cellular immune response to Helicobacter pylori infection. The higher levels of tumour necrosis factor production by antral mucosa cells in Helicobacter pylori positive patients may reflect the infiltration of T lymphocytes and macrophages within the local mucosa.

[In vitro effect of catechin on cell growth]

Experimental study on the effect of catechin, an extract of Chinese green tea, on cell growth of HeLa, KB and 3T3 cell lines and its possible mechanism are reported. The proliferative survival curves showed that HeLa and KB were sensitive to catechin, while 3T3 was less so. The survival curve of HeLa cells treated with catechin varied with the dose and duration of exposure. 3H-TdR incorporation rate into HeLa cells was inhibited by catechin and the inhibition rate was also dose and exposure dependent. It suggests that one of the mechanisms of cell growth inhibition by catechin may probably due to inhibition of DNA synthesis.

Levels of O6-methylguanine acceptor protein in extracts of human breast tumor tissues

We have measured the abilities of extracts of tissues from human breast tumors to demethylate adducts of O6-meG in exogenous DNA by transfer of the methyl group to an acceptor protein. The results have shown that all 21 specimens examined (including 5 non-neoplastic, 11 malignant tumors and 5 benign growth) contained significant amounts of O6-meG acceptor activity, removing on average 221.1 +/- 2.1 (SEM) fmol O6-meG per mg protein or 10.07 +/- 0.98 (SEM) fmol O6-megG per microgram DNA in the extracts. There were also wide interindividual variations, which were not age-dependent, and there were no significant differences between the non-neoplastic and neoplastic tissues obtained from individuals with benign or with malignant disease. It was estimated that the average number of O6-meG acceptor molecules per cell in normal human breast tissues was calculated as 46,000 +/- 7000 (SEM).

[Experimental studies on the hyperthermia-photodynamic effect of tumor cells photosensitized with Y-HpD]

Experimental studies were made on the hyperthermia-photodynamic effect of tumor cells photosensitized with Y-HpD (China-made). Fluorescence spectra were determined in different animal and human cancer tissues before and after treatment. The results showed: Hyperthermia (42-44 degrees C) significantly increased the efficacy of photodynamic therapy (PDT) with a prolongation of survival time of mice and significant difference between PDT groups with and without hyperthermia (P less than 0.05). However, this difference was not present with mild hyperthermia (39-40 degrees C); A new fluorescence band was first observed in animal and human cancer cells after PDT treatment (with or without hyperthermia), with a maximum emission wave-length of 460 nm (excitation wave-length, 370 nm). The intensity of the band being correlated with cancer cell destruction, and the highest fluorescence intensity together with the strongest cytocidal effect were seen in the PDT-plus-heat group. Most Y-HpD was found the cytoplasm after treatment, with little Y-HpD left in the nucleus. The amount of Y-HpD in the cells decreased with the formation of fluorophores in the cytoplasm as a product of photochemical reactions. The authors suggest that hyperthermia may activate Y-HpD, and the increase of cellular Y-HpD then enhances the photochemical reaction.

Hematoporphyrin derivative photosensitization and cellular fluorescent photoproduct formation

A new fluorescence band with an emission maximum at 460 nm was observed in S180 tumour cells and human cancer tissues photosensitized by Y-HPD. This fluorescence was the result of a photochemical reaction involving specific proteins and Y-HPD in the cells.

[Photodynamic therapy (PDT) of bladder cancer in the rat]

PDT of rat bladder cancer, induced by N-butyl-N-(4-hydroxybutyl) nitrosamine (BBN) was studied. All animals were divided at random into three groups. Group 2 and 3 were treated by hematoporphyrin derivative (HPD)-laser PDT while group 1, without treatment, served as control. The results showed that the malignant lesions could be selectively and obviously destroyed, if the whole tumor area were sufficiently exposed to the laser irradiation. However, the normal bladder epithelium and muscle layer showed no histologic change. Similar reactions were found in papilloma of bladder which was considered as precancerous lesion. Thus, PDT may be beneficial to cancer prevention. Its role in prevention and treatment of bladder cancer should be further studied experimentally and clinically.

The biological effects of photodynamic therapy on normal skin in mice--I. A light microscopic study

A light microscopic investigation of the biological effects of photodynamic therapy using hematoporphyrin derivative and red light irradiation has been carried out. HpD alone, even used at a dose of 50 mg/kg, did not cause histologically discernible changes. The irradiation alone used in this experiment caused only slight or moderate dilatation and congestion of blood vessels, which disappeared completely within several hours after light exposure. In the PDT treated mouse ears severe degeneration and necrosis of skin tissue occurred within 1-2 days. The importance of adequate drug and light doses and proper interval chosen for obtaining best therapeutic effects and protection of surrounding normal tissues was pointed out. The possible mechanism of the PDT action in vivo was briefly discussed.

The biological effects of photodynamic therapy on normal skin in mice--II. An electron microscopic study

In the present study it has been demonstrated that the ultrastructural changes in mouse ear skin after PDT action occurred much more distinct and earlier than those observed in the histological study. Various types of cells in the skin respond to the photodynamic action differently. The endothelial cells, fibroblasts and nerve fibers are most sensitive. In contrast, the keratinocytes and chondrocytes often remain rather well preserved after PDT treatment. The possible mechanism of PDT action was briefly discussed.