Over-expressed human divalent metal transporter 1 is involved in iron accumulation in MES23.5 cells

Elevated iron accumulation has been reported in brain regions in some neurodegenerative disorders. However, the mechanism for this is largely unknown. Divalent metal transporter 1 (DMT1) is an important divalent cation transporter. The aim of the present study is to construct recombinant adenovirus encoding human DMT1 with iron responsive element (DMT1+IRE) and infect MES23.5 dopaminergic cells in order to investigate the relationship between increased DMT1+IRE expression and iron accumulation. The human DMT1 gene was obtained by RT-PCR from tissues of human duodenum. AdDMT1+IRE was successfully constructed and identified by PCR, restriction endonuclease analyses and DNA sequencing, respectively. It was able to efficiently infect MES23.5 cells, which was confirmed by RT-PCR and Western blots. When incubated with 100 microM ferrous iron for 6h, the intracellular iron levels dramatically increased in AdDMT1+IRE infected MES23.5 cells compared to the solely adenovirus infected cells. Meanwhile, the levels of hydroxyl free radicals and malondialdehyde (MDA) in these cells increased. This led to the activation of caspase-3. The apoptosis in AdDMT1+IRE infected cells was shown with hypercondensed nuclei using Hoechst staining. Analysis of DNA extracted from these cells showed the typical "ladder pattern", indicating the formation of mono- and oligonucleosomes. These results suggested that increased DMT1+IRE expression in MES23.5 cells caused the increased intracellular iron accumulation. This resulted in the increased oxidative stress leading to ultimate cell apoptosis.

[Protective effect of recombinant adenovirus carrying rat insulin-like growth factor 1 on rat islet beta-cell against strepozotocin-induced impairment in vitro]

OBJECTIVE

To construct the recombinant adenovirus containing rat insulin-like growth factor 1 (rIGF-1), and then infect to rat islet beta cells-RINm5F cells with the virus to investigate the role of rIGF-1 to streptozotocin-induced cell impairment in vitro.

METHODS

Recombinant adenovirus encoding rIGF-1 was constructed, and then infect to RINm5F cells. rIGF-1 protein was detected by Western blot analysis and ELISA method. Then streptozotocin was used to induce RINm5F cells impairment. The levels of nitric oxide were detected in cells culture supernatants. The cells function was evaluated by glucose-stimulated insulin production. The apoptosis was analyzed by flow cytometry. Thiaoollyl blue viability assay was applied to exam the number of viable cells.

RESULTS

The recombined adenovirus-rIGF-1 was constructed successfully and its titer was about 4.0x10(8) pfu/ml. The rIGF-1 was expressed in the RINm5F cells and cell culture supernatants. rIGF-1 expression could inhibit islet cells apoptosis, significantly decrease the level of NO induced by streptozotocin and significantly increase insulin secretion and cells viability.

CONCLUSION

These results suggested that the high concentration of rIGF-1 in cultured islets may be beneficial in maintaining islet beta cells function and protecting islet beta cells from apoptosis-mediated factors. The apoptosis induced by STZ may be NO-dependent.

Metabolic flux analysis at ultra short time scale: Isotopically non-stationary 13C labeling experiments

A novel approach to (13)C metabolic flux analysis (MFA) is presented using cytosolic metabolite pool sizes and their (13)C labeling data from an isotopically non-stationary (13)C labeling experiment (INST-CLE). The procedure is demonstrated with an E. coli wild type strain grown at fed batch conditions. The intra cellular labeling dynamics are excited by a sudden step increase of the (13)C portion in the substrate feed. Due to unchanged saturation of the substrate uptake system, the metabolic fluxes remain constant during the following sampling time period of only 16s, in which 20 samples are taken by an automated rapid sampling device immediately stopping metabolism by methanol quenching. Subsequent cell disruptive sample preparation and LC-MS/MS enabled simultaneous determination of pool sizes and mass isotopomers of intra cellular metabolites requiring detection limits in the nM range. Based on this data the new computational flux analysis tool 13CFLUX/INST is used to determine the intra cellular fluxes based on a complex carbon labeling network model. The measured data is in good agreement with the model predictions, thus proving the applicability of the new isotopically non-stationary (13)C metabolic flux analysis (INST-(13)C-MFA) concept. Moreover, it is shown that significant new information with respect to flux identifiability, non-measurable pool sizes, data consistency, or large storage pools can be taken from the novel kind of experimental data. This offers new insight into the biological operation of the metabolic network in vivo.

Toward quantifying the effectiveness of water trading under uncertainty

This paper presents a methodology for quantifying the effectiveness of water-trading under uncertainty, by developing an optimization model based on the interval-parameter two-stage stochastic program (TSP) technique. In the study, the effectiveness of a water-trading program is measured by the water volume that can be released through trading from a statistical point of view. The methodology can also deal with recourse water allocation problems generated by randomness in water availability and, at the same time, tackle uncertainties expressed as intervals in the trading system. The developed methodology was tested with a hypothetical water-trading program in an agricultural system in the Swift Current Creek watershed, Canada. Study results indicate that the methodology can effectively measure the effectiveness of a trading program through estimating the water volume being released through trading in a long-term view. A sensitivity analysis was also conducted to analyze the effects of different trading costs on the trading program. It shows that the trading efforts would become ineffective when the trading costs are too high. The case study also demonstrates that the trading program is more effective in a dry season when total water availability is in shortage.

Carboxyl-terminal sequence variation of latent membrane protein 1 gene in Epstein-Barr virus-associated gastric carcinomas from Eastern China and Japan

OBJECTIVES

To elucidate variations of latent membrane protein 1 (LMP1) in Epstein-Barr virus (EBV)-associated gastric carcinoma (EBVaGC) and explore the LMP1 variations of neighboring countries, China and Japan.

METHODS

In 12 and 8 EBVaGCs from eastern China and Japan, respectively, the C-termini of LMP1 were analyzed using PCR and sequencing. The sequences were compared with previously published strains and were characterized on a phylogenetic tree. The difference between Chinese and Japanese isolates was characterized.

RESULTS

Ten of 12 Chinese GC isolates (83.3%) and all of the 8 (100%) Japanese GC isolates belonged to the China 1 strain. Also, B95-8 type isolates were found in 2 of 12 Chinese GC. In the 18 China 1 type isolates, additional mutations outside the signature sequence changes were found. All Japanese isolates (100%) had two or more additional mutations, whereas only 5 of 10 (50%) Chinese isolates had two or more additional mutations. The difference was statistically significant (p = 0.0359).

CONCLUSIONS

China 1 is the dominant strain in GC from eastern China and Japan. The similarity to that of nasopharyngeal carcinoma (NPC) from China supports the view that China 1 strain represents a geographic-associated polymorphism rather than an NPC-associated polymorphism. Japanese isolates show more mutations than Chinese isolates, suggesting a geographic difference between Chinese and Japanese isolates in GC.

Diabetes induces rapid suppression of adaptive immunity followed by homeostatic T-cell proliferation

Surprisingly, the effect of acute diabetes on immunity has not been examined in detail. We, herein, show for the first time that untreated acute diabetes causes rapid lymphopenia followed by homeostatic T-cell proliferation. The diabetes-induced lymphopenia was associated with an immunosuppressed state that could be sufficiently strong to allow engraftment of fully allogeneic beta-cells or block rejection of islet transplants. In contrast, homeostatic proliferation and recovery of T-cell numbers were associated with islet rejection. Thus, the timing of islet transplant challenge in relation to diabetes induction was critical in determining whether islets were accepted or rejected. In addition, we tested whether diabetes-related immunosuppression could result in an overestimation of the efficacy of a tolerance-inducing protocol. Consistent with this possibility, a protocol targeting CD40L and ICOS that we have shown induces tolerance in diabetic recipients was unable to induce tolerance in non-diabetic recipients. The data uncover a previously unrecognized suppressive effect of diabetes on adaptive immunity. Furthermore, they suggest that the standard methods of testing new tolerance-inducing protocols in islet transplantation require modification and that diabetes itself can contribute to homeostatic proliferation, a process associated with autoimmunity and a resistance to tolerance induction.

Influence of Epstein-Barr virus latent membrane protein 2A on the proliferation of human gastric cancer cells

AIM: To construct recombinant adenovirus expression vector containing Epstein-Barr virus (EBV) latent membrane protein 2A (LMP2A) and investigate the effects of LMP2A on the proliferation of human gastric cancer cell line.

METHODS: The target gene LMP2A was amplified by reverse transcription-polymerase chain reaction (RT-PCR), and the recombinant adenovirus vector carrying LMP2A gene was constructed with AdEasy system. The recombinant adenovirus vector pAd-2A was transfected into HEK293 cells with lipofectamine 2000 to package recombinant adenovirus, and then gastric cancer cells SGC with negative EBV were infected by recombinant adenovirus. The expression of LMP2A and its effect on the proliferation of SGC cells were analyzed by PT-PCR, MTT assay, fluorescence activated cell sorting (FACS) and confocal microscopy.

RESULTS: The recombinant adenovirus vector pAd-2A was successfully constructed and identified by PCR, restrictive enzyme analysis, and DNA sequencing. The recombinant adenovirus vAd-2A packaged by HEK293 cells had stable infectivity. The virus titer was 3.16×10¹² pfu/L. MTT assay, FACS and confocal microscopy showed that vAd-2A transfection significantly increased the proliferation of SGC cells (P < 0.01). The ratio of S-phase cells was markedly elevated after vAd-2A transfection in comparison with that after vAd transfection and non-transfection (24 h: 35.2% ± 5.1% vs 14.0% ± 3.4%, 13.2% ± 4.6%, P < 0.01; 48 h: 25.6% ± 4.1% vs 12.9% ± 2.6%, 12.5% ± 3.2%, P < 0.01). The expression of Cyclin E protein was also induced by LMP2A.

CONCLUSION: The recombinant adenovirus vector carrying EBV LMP2A gene is constructed successfully. Meanwhile, it is confirmed that LMP2A may promote the proliferation of SGC cells by induction of Cyclin E expression.

[Construction and package of the expression plasmid pAdEasy-1 system encoding the human papillomavirus 16 E7 gene and the gene's influence on HeLa cells]

OBJECTIVE

To investigate the effect of human papillomavirus 16 E7 gene on cell cycle of cervical cancer HeLa cell, through construction and expression of human papillomavirus 16 E7 gene with adenovirus vector.

METHODS

Recombinant adenovirus which expressed E7 gene was constructed and packed. Flow cytometry (FCM) was used to detect the changes of cell cycle phase and cyclin D1 between cells infected and uninfected by recombinant adenovirus. The 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphennyltetrazolium bromide (MTT) colorimetric assay was used in the detection of the alteration of cell growth.

RESULTS

The recombinant adenovirus had stable efficiency of infection and E7 genes could be expressed stably. The result of MTT showed the multiplication of HeLa cells was accelerated from 0.27 +/- 0.03 before infection to 0.38 +/- 0.02 after infection (P < 0.01). FCM showed the number of cells in S phase increased from (26.0 +/- 0.4)% to (36.0 +/- 2.0)% at 12 hours and (49.9 +/- 4.2)% at 24 hours after infection (P < 0.05). Cyclin D1 expression was 22.4% before infection, and decreased to 55.2% after infection (P < 0.01).

CONCLUSIONS

The recombinant adenovirus expressing E7 gene could infect target cells. E7 gene can influence cell-cycle of HeLa cells, which can be used to restrain cervical cancer.

Absence of GABA type A signaling in adult medial habenular neurons

Neural inhibition in the brain is mainly mediated by ionotropic GABA type A receptors. Apart from the GABA type A receptors, both K(+)-Cl(-) cotransporter isoform 2 and the GABA-synthesizing enzyme, glutamic acid decarboxylase, are essential determinants for GABA type A receptor-mediated inhibition. By using immunofluorescent staining, we observed that K(+)-Cl(-) cotransporter isoform 2, GABA type A receptor beta2/3 subunits and a presynaptically localized glutamic acid decarboxylase isoform, glutamic acid decarboxylase 65, were all absent in adult Sprague-Dawley rat medial habenular nucleus, while immunopositive staining for glutamic acid decarboxylase 67, GABA and GABA type B receptor type 2 subunit were present in the medial habenular nucleus. Consistent with the lack of GABA type A signaling as detected by immunohistochemistry, GABA (100 muM) evoked no measurable currents in the medial habenular nucleus but induced bicuculline-sensitive currents in the lateral habenular nucleus and in the CA1 area of hippocampus. We also failed to record miniature inhibitory postsynaptic currents in medial habenular nucleus neurons. These results support the idea that GABAergic transmission in medial habenular nucleus is probably not mediated by any of the most common GABA type A receptor subtypes. Our data suggest that GABA type B receptor-mediated inhibition may play a role in balancing neuronal excitation in this special region. Further exploration for factors determining medial habenular nucleus neural inhibition will lead to a more complete understanding of control of synaptic balance in the CNS.

A simulation-based interval two-stage stochastic model for agricultural non-point source pollution control through land retirement

This study presents a simulation-based interval two-stage stochastic programming (SITSP) model for agricultural non-point source (NPS) pollution control through land retirement under uncertain conditions. The modeling framework was established by the development of an interval two-stage stochastic program, with its random parameters being provided by the statistical analysis of the simulation outcomes of a distributed water quality approach. The developed model can deal with the tradeoff between agricultural revenue and "off-site" water quality concern under random effluent discharge for a land retirement scheme through minimizing the expected value of long-term total economic and environmental cost. In addition, the uncertainties presented as interval numbers in the agriculture-water system can be effectively quantified with the interval programming. By subdividing the whole agricultural watershed into different zones, the most pollution-related sensitive cropland can be identified and an optimal land retirement scheme can be obtained through the modeling approach. The developed method was applied to the Swift Current Creek watershed in Canada for soil erosion control through land retirement. The Hydrological Simulation Program-FORTRAN (HSPF) was used to simulate the sediment information for this case study. Obtained results indicate that the total economic and environmental cost of the entire agriculture-water system can be limited within an interval value for the optimal land retirement schemes. Meanwhile, a best and worst land retirement scheme was obtained for the study watershed under various uncertainties.

Ras mutation and expression of farnesyltransferase β mRNA in Epstein-Barr virus-associated gastric carcinoma

AIM: To investigate ras gene mutations and farnesyltransferase (FTase) β mRNA expression in Epstein-Barr virus(EBV)-associated gastric carcinoma (EBVaGC), EBV-negative gastric carcinoma (EBVnGC) with matched clinico-pathological parameters and corresponding adjacent tissues of gastric carcinoma.

METHODS: The mutations of ras gene were detected by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and the expression of FTase β mRNA was tested by reverse transcription PCR (RT-PCR) in 13 EBVaGCs, 45 EBVnGCs with matched clinicopathological parameters and 58 corresponding adjacent tissues of gastric carcinoma.

RESULTS: H-ras mutation at codon 12 was detected in 2(3.45%) cases of gastric carcinomas, both of which were EBVnGCs. No K-ras mutations occurred at codon 12 and 13 in all cases. The level of FTase β mRNA expression was 0.93 ± 0.39 in gastric carcinomas and 0.78 ± 0.26 in corresponding adjacent tissues, respectively. The difference between the two groups was significant (t = 2.44, P = 0.02). The level of FTase β mRNA expression was 0.80 ± 0.19 in EBVaGCs and 0.96 ± 0.43 in EBVnGCs respectively. The difference between the two groups was not significant (t = 1.93, P = 0.06). FTase β mRNA expression was not significantly different (t = 0.54, P = 0.60) between EBVaGCs and corresponding adjacent tissues either, while it was significant (t = 2.39, P = 0.02) between EBVnGCs and corresponding adjacent tissues. The level of FTase β mRNA expression had no significant relationship between 2 BHRF1 positive samples and 11 BHRF1 negetive samples of EBVaGCs (t = 0.26, P = 0.80) as well as between 6 BARF1 positive samples and 7 BARF1 negetive samples of EBVaGCs (t = 1.59, P = 0.14).

CONCLUSION: The frequency of ras gene mutations in gastric carcinomas is low in this study. The level of FTase β mRNA expression in gastric carcinomas is much higher than that in normal tissues. EBV infection has no significant correlations with ras mutations and FTase expression in EBVaGC.

Correlation of Epstein-Barr virus and its encoded proteins with Helicobacter pylori and expression of c-met and c-myc in gastric carcinoma

AIM

To investigate the interrelationship of Epstein-Barr virus (EBV) and EBV- encoded proteins with Helicobacter pylori (H pylori) infection and the expression of c-met and c-myc oncogene proteins in gastric carcinoma, and to explore their role in gastric carcinogenesis.

METHODS

One hundred and eighty-five gastric carcinoma tissues were detected by polymerase chain reaction (PCR)-Southern blot for EBV genome and in situ hybridization (ISH) for EBV-encoded small RNA 1 (EBER1). Gastric carcinoma with positive EBER1 signals was confirmed EBV-associated gastric carcinoma (EBVaGC). The status of H pylori infection in 185 gastric carcinomas was assessed by rapid urease test and PCR. The samples with positive PCR and urease test were defined as H pylori infection. The expression of c-met and c-myc oncogene proteins in tissues of EBVaGC and matched EBV-negative gastric carcinoma (EBVnGC) were examined by immunohistochemistry. RT-PCR and Southern hybridization were used to detect the expression of nuclear antigens (EBNAs) 1 and 2, latent membrane protein (LMP) 1, early genes BARF1 and BHRF1 in EBVaGC cases.

RESULTS

The positive rate of H pylori and EBV in 185 gastric carcinomas was 59.45% (110/185) and 7.03% (13/185) respectively. No difference was found in sex, age, pathological differentiation, clinical stages and lymph node metastasis between H pylori-positive and H pylori-negative gastric carcinomas. However, the positive rate of H pylori infection in the antrum gastric carcinomas was higher than that of cardia and body gastric carcinomas. In our series, age, pathological differentiation, clinical stages, lymph node metastasis and location of cancer were not different between EBVnGC and EBVaGC, while the positive rate of EBV in male patients was significantly higher than that of female patients. The positivity of H pylori in EBV-associated and EBV-negative gastric carcinomas was 46.15% (6/13) and 81.40%(104/172) respectively. There was no significant correlation between EBV and H pylori infection. The c-met overexpression was significantly higher in the EBVaGC group than in the EBVnGC group. However, c-met and c-myc expression did not show significant difference between the two groups. Transcripts of EBNA1 were detected in all 13 EBVaGCs, while both EBNA2 and LMP1 mRNA were not detected. Six of the 13 cases exhibited BARF1 transcripts and 2 exhibited BHRF1 transcripts.

CONCLUSION

The positivity of H pylori in EBVnGCs is higher than that of EBVaGCs, but no significant correlation is found between EBV infection and H pylori infection. H pylori-positive gastric carcinoma is predominant in antrum location, while EBVaGC has a tendency of predominance in cardia/body location. EBV infection is associated with c-met abnormal expression but not with c-myc protein in EBVaGC. c-met overexpression is not induced by LMP1. BARF1 and BHRF1 may play important roles in the tumorigenesis of EBVaGC through different pathways.

Apoptosis induced by preoperative oral 5’-DFUR administration in gastric adenocarcinoma and its mechanism of action

AIM: To study the apoptosis induced by preoperative oral 5’-DFUR administration in gastric adenocarcinoma and its mechanism of action.

METHODS: Sixty gastric cancer patients were divided randomly into three groups (20 each group) before operation: group one: 5’-DFUR oral administration at the dose of 800-1200mg/d for 3 - 5 d, group two: 500mg 5-FU + 200 mg/d CF by venous drip for 3 - 5 d, group three (control group). One or two days after chemotherapy, the patients were operated. Fas/FasL, PD-ECGF and PCNA were examined by immunohistochemistry and apoptotic tumor cells were detected by in situ TUNEL method. Fifty-four patients received gastrectomy, including 12 palliative resections and 42 radical resections. Six patients were excluded. Finally 18 cases in 5’-DFUR group, 16 cases in CF + 5-FU group, and 20 cases in control group were analyzed.

RESULTS: There was no significant difference in patient mean age, gender, white blood cell count, haematoglobin (HB), thromboplastin, perioperative complication incidence, radical or palliation resection, invasion depth (T), lymphonode involvement (N), metastasis (M) and TNM staging among the three groups. However, the PCNA index (PI) in 5’-DFUR group (40.51 ± 12.62) and 5-FU + CF group (41.12 ± 15.26) was significantly lower than that in control group (58.33 ± 15.69) (F = 9.083, P = 0.000). The apoptotic index (AI) in 5’-DFUR group (14.39 ± 9.49) and 5-FU + CF group (14.11±9.68) was significantly higher than that in control group (6.88 ± 7.37) (F = 4.409, P = 0.017). The expression rates of Fas and FasL in group one and group three were 66.7% (12/18) and 50% (9/18), 43.8% (7/16) and 81.3% (13/16), 45.0% (9/20) and 85% (17/20), respectively. The expression rate of FasL in 5’-DFUR group was significantly lower than that in the other two groups (χ²=6.708, P = 0.035). Meanwhile, the expression rate of PD-ECGF was significantly lower in 5’-DFUR group (4/18，28.6%) than in CF + 5-FU group（9/16，56.3%）and control group (13/20，65.0%) (χ²= 7.542, P = 0.023). The frequency of Fas expression was significantly correlated with palliative or radical resection (χ²= 7.651, P = 0.006), invasion depth (χ²= 8.927, P = 0.003), lymphatic spread (χ²= 4.488, P = 0.034) and UICC stages (χ²= 8.063, P = 0.045) respectively. By the end of March 2005, 45 patients were followed up. The 0.5-, 1-, 2-, 3-year survival rates were 96%，73%，60%，48%, respectively, which were related with T, N, M and Fas expression, but not with PD-ECGF and FasL expression.

CONCLUSION: Preoperative oral 5’-DFUR administration may induce apoptosis of gastric carcinoma cells and decrease tumor cell proliferation index, but cannot improve the prognosis of patients with gastric cancer. Down-regulation of FasL and PD-ECGF expression mediated by 5’-DFUR may be one of its anti-cancer mechanisms. Fas expression correlates with the progression of gastric carcinoma and may be an effective prognostic factor.

[Effect of small interference RNA on E6, E7 mRNA of human papillomavirus type-18 in cervical cancer cells]

OBJECTIVE

To study the effect of small interference RNA on E6, E7 mRNA of human papillomavirus type-18 (HPV18) in cervical cancer cells.

METHODS

The specific HPV18E6 and E7 siRNA synthesized by in virtro transcription. The cell activity was detected by methyl thiazolyl tetrazolium (MTT) assay to determine the most suitable concentration, then cells were transfected into HPV18 cervical cancer cells by oligofectamine. HPV18E6, E7 mRNA level was examined by semi-quantitative RT-PCR, and the cell cycles were analyzed by flow cytometry.

RESULTS

The activity of the HeLa cells had an obvious suppression after transfection to 0.57 +/- 0.05 and 0.62 +/- 0.04 compared with the contrast of 0.87 +/- 0.05. The expression of HPV18E6 mRNA level was 0.63 +/- 0.04 before transfection, decreased to 0.53 +/- 0.04, 0.46 +/- 0.02, 0.56 +/- 0.03 evidently after transfection at 24, 48, 72 hours. The expression of HPV18E7 mRNA level was 0.66 +/- 0.03 before transfection and decreased to 0.60 +/- 0.05, 0.52 +/- 0.04, 0.59 +/- 0.02 after transfection at 24, 48, 72 hours. The number of cells in G(2) phase was increased after HPV18E6 siRNA transfection from (1.4 +/- 1.2)% to (66.9 +/- 3.5)%, S phase was declined from (39.4 +/- 0.4)% to (0 +/- 5.5)%, and they were (47.2 +/- 0.5)% and (5.6 +/- 4.2)% in E7 group.

CONCLUSION

RNAi exists in HeLa cells, and its effect has specificity.

Hydrido and chloro gallium and aluminium complexes with the tridentate bis(2-dimethylaminoethyl)amide ligand

Five-coordinate gallium and aluminium dihydrides, H2Ga[N(CH2CH2NMe2)2] () and H2Al[N(CH2CH2NMe2)2] (), were synthesized and found to be volatile and thermally stable. and reacted with H3Ga(NMe3) and H3Al(NMe3), respectively, to form H2Ga[N(CH2CH2NMe2)2]GaH3 () and H2Al[N(CH2CH2NMe2)2]AlH3 (), in which the amido nitrogen bridged between the MH2 and MH3 groups (M=Ga or Al). A mixed metal complex, H2Al[N(CH2CH2NMe2)2]GaH3 () was obtained from the reaction of with H3Al(NMe3) or with H3Ga(NMe3), and a crystal consisting of a mixture of and was structurally characterized. The five-coordinate chloro derivative, Cl2Ga[N(CH2CH2NMe2)2] (), was synthesized and characterized.

An inexact fuzzy two-stage stochastic model for quantifying the efficiency of nonpoint source effluent trading under uncertainty

Reduction of nonpoint source (NPS) pollution from agricultural lands is a major concern in most countries. One method to reduce NPS pollution is through land retirement programs. This method, however, may result in enormous economic costs especially when large sums of croplands need to be retired. To reduce the cost, effluent trading can be employed to couple with land retirement programs. However, the trading efforts can also become inefficient due to various uncertainties existing in stochastic, interval, and fuzzy formats in agricultural systems. Thus, it is desired to develop improved methods to effectively quantify the efficiency of potential trading efforts by considering those uncertainties. In this respect, this paper presents an inexact fuzzy two-stage stochastic programming model to tackle such problems. The proposed model can facilitate decision-making to implement trading efforts for agricultural NPS pollution reduction through land retirement programs. The applicability of the model is demonstrated through a hypothetical effluent trading program within a subcatchment of the Lake Tai Basin in China. The study results indicate that the efficiency of the trading program is significantly influenced by precipitation amount, agricultural activities, and level of discharge limits of pollutants. The results also show that the trading program will be more effective for low precipitation years and with stricter discharge limits.

Relationship between Epstein-Barr virus-encoded proteins with cell proliferation, apoptosis, and apoptosis-related proteins in gastric carcinoma

AIM: To investigate the interrelationship between Epstein-Barr virus (EBV)-encoded proteins and cell proliferation, apoptosis and apoptosis-related proteins in gastric carcinoma, and to explore their role in gastric carcinogenesis.

METHODS: Tissues from 13 cases of EBV-associated gastric carcinoma (EBVaGC) and 45 cases of matched EBV-negative gastric carcinoma (EBVnGC) were collected, and then subjected to analysis for apoptotic index (AI) using the terminal deoxynucleotidyl transferase (TdT)-mediated dUTP-biotin nick end-labeling (TUNEL) assay. Nuclear cell proliferation-associated antigen ki-67 index (KI), bcl-2, and p53 expression were examined by immunohistochemistry. p53 mutation in exons 5-8 of 13 EBVaGC cases was determined by single-strand conformation polymorphism (SSCP) and DNA sequencing. RT-PCR and Southern hybridization were used to detect the expression of nuclear antigens (EBNAs) 1 and 2, latent membrane protein (LMP) 1, immediately early gene BZLF1 and early genes BARF1 and BHRF1 in 13 EBVaGC cases.

RESULTS: The percentage of AI, KI and p53 overexpression was significantly lower in the EBVaGC group than in the EBVnGC group. However, bcl-2 expression did not show significant difference between the two groups. p53 gene mutations were not found in 13 EBVaGCs. Transcripts of EBNA1 were detected in all 13 EBVaGCs, while both EBNA2 and LMP1 mRNA were not detected. Six of the thirteen cases exhibited BZLF1 transcripts and two exhibited BHRF1 transcripts. BARF1 mRNA was detected in six cases.

CONCLUSION: Lower AI and KI may reflect a low biological activity in EBVaGC. EBV infection is associated with p53 abnormal expression but not bcl-2 protein in EBVaGC. BZLF1, BARF1, and BHRF1 may play important roles in inhibiting cell apoptosis and tumorigenesis of EBVaGC through different pathways.

[Expression of heat shock protein 72 in leukocytes from patients with acute trauma and its relationship with survival]

OBJECTIVE

To determine the expression of heat shock protein 72 (HSP 72) in leukocytes of patients with acute trauma, and evaluate its relationship with survival.

METHODS

Thirty acute trauma patients with acute physiology and chronic health evaluation III (APACHE III) > or = 18 were included as study subjects. Blood samples were serially obtained at three time points: days 0-1, days 2-6 and days 7-14 after the trauma. Expression of HSP72 was assessed with immunohistochemistry, and the expression of HSP72 mRNA was assessed with semi-quantified reverse transcription-polymerase chain reaction (RT-PCR), and the relationship between their levels and the survival rate (survival period > 2 months) was analyzed.

RESULTS

The expression of HSP72 was significantly enhanced on post-trauma days 2-6. The levels of HSP72 in the survivor groups were higher than that in non-survivors.

CONCLUSION

The study suggests that acute trauma can lead to a marked elevation of HSP72, and its peak level appears on days 2-6, which might be correlated with 2-month survival of the afflicted patients.

Expression of Epstein-Barr virus genes in EBV-associated gastric carcinomas

AIM: To understand the expression of latent and lytic genes of Epstein-Barr virus (EBV) in EBV-associated gastric carcinoma (EBVaGC) and to explore the relationship between EBV-encoded genes and development of EBVaGC at molecular level.

METHODS: One hundred and seventy-two gastric carcinoma tissues and 172 corresponding para-carcinoma tissues were tested for EBV genome by polymerase chain reaction (PCR)-Southern blotting. EBV-encoded small RNA (EBER) 1 of the PCR positive specimens was detected by in situ hybridization (ISH). Gastric carcinomas with positive EBER1 signals were classified as EBVaGCs. RT-PCR and Southern hybridization were applied to the detection of expression of nuclear antigen (EBNA) promoters (Qp, Wp and Cp), EBNA 1 and EBNA 2, latent membrane proteins (LMP) 1, 2A and 2B and lytic genes (immediate early genes BZLF1 and BRLF1, early genes BARF1 and BHRF1, late genes BcLF1 and BLLF1) in EBVaGCs.

RESULTS: Eleven EBV positive samples existed in gastric carcinoma tissues (6.39%). No EBV positive sample was found in corresponding para-carcinoma tissues. The difference between EBV positivity in carcinoma tissues and corresponding para-carcinoma tissues was significant (χ² = 9.0909, P = 0.0026). Transcripts of Qp and EBNA1 were detected in all the 11 EBVaGCs, while both Wp and Cp were silent. EBNA2, LMP1 and LMP2B mRNA were absent in all the cases, while LMP2A mRNA was detected in 4 of the 11 cases. Of the 11 EBVaGCs, 7 exhibited BcLF1 transcripts and 2 exhibited BHRF1 transcripts. The transcripts of BZLF1 and BARF1 were detected in 5 cases, respectively. No BLLF1 and BRLF mRNA were detected.

CONCLUSION: The latent pattern of EBV in gastric carcinoma corresponds to the latency I/II. Some lytic infection genes are expressed in EBVaGCs tissues. BARF1 and BHRF1 genes may play an important role in tumorigenesis of gastric carcinoma.

Relationship between Epstein-Barr virus and overexpression of c-Met protein in gastric carcinoma

AIM: To detect the amplification and expression of c-Met in Epstein-Barr virus (EBV)-associated gastric carcinoma (EBVaGC) and EBV-negative gastric carcinoma (EBVnGC), and to investigate the relationshi pof the amplification and expression of c-Met with EBV infection in the process of gastric carcinogenesis.

METHODS: The amplification of c-Met gene and the expression of c-Met protein in the tissues of EBVaGC (n = 13) and EBVnGC (n = 45) were detected by semi-quantitative polymerase chain reaction (PCR) and immunohistochemical methods, respectively.

RESULTS: The amplification of c-Met was observed in both EBVaGC and EBVnGC. The overamplification rates were 53.8% (7/13) in EBVaGC and 44.4% (20/45) in EBVnGC. There was no significant difference between the two types of caners. c-Met protein was positive in 76.9% (10/13) EBVaGC, and 64.4% (29/45) EBVnGC tissues. The difference between them was not significant either. The overexpression rate of c-Met protein in EBVaGC was significantly higher than that in EBVnGC (69.2% vs 37.8%, P = 0.0 446). No significant correlation was observed between the amplification and expression of c-Met with the tumor size, location, lymph node metastasis, differentiation degree or clinical staging.

CONCLUSION: c-Met is amplified in both EBVaGC and EBVnGC tissues. The amplification level of c-Met gene and the positive rate of c-Met protein are not significantly different between EBVaGC and EBVnGC. However, the overexpression rate of c-Met protein in EBVaGC is higher than that in EBVnGC.

Mono- and digallane complexes of a tridentate amido-diamine ligand

Bis(2-dimethylaminoethyl)amido gallane, H2GaN(CH2CH2NMe2)2, that melts at 27 degrees C and remains stable upon heating at 55 degrees C for two days, was synthesized either from the reaction of the quinuclidine adduct of monochlorogallane with the lithium salt of the corresponding amine, or from the reaction of trimethylamine gallane and the amine; the latter affords an unusual co-product with both GaH2 and GaH3 bonded to the same amido nitrogen.

Tachykinin NK3-receptor deficiency does not inhibit pulmonary eosinophilia in allergic mice

Tachykinins are important in the development of pulmonary inflammation in mice but the tachykinin receptor subtype mediating this response has not been defined. To elucidate the role of tachykinin NK3-receptors on allergen-induced pulmonary inflammation, studies were performed on ovalbumin (OVA) sensitized and challenged mice with genetic disruption of the tachykinin NK3-receptor (NK3-/-). Aerosol OVA (0.5%) challenge produced eosinophil influx into the bronchoalveolar lavage fluid and lung tissue, goblet cell hyperplasia and damage to the airway epithelium of both NK3-/- mice and in wild type control mice (NK3+/+). There was no difference in the magnitude of these allergic inflammatory pulmonary responses between NK3-/- and NK3+/+ mice. These results find no role for tachykinin NK3-receptors on the pulmonary eosinophilia and lung damage after antigen challenge in mice.