Genotoxicity Evaluation of an Urban River on Freshwater Planarian by RAPD Assay

The aim of this study was to evaluate the genotoxic potential of an urban river - the Wei River in Xinxiang, China using randomly amplified polymorphic DNA (RAPD) assay in planarians. The results showed that the total number of polymorphic bands and varied bands in RAPD patterns of treated planarians decreased with the water sample site far away from the sewage outlet of a factory. In addition, the genome template stability of treated groups decreased and the degree of the decline was negatively related to the distance between the sample site and the sewage outlet, suggesting that the Wei River water had genotoxicity effects on planarians and strengthening the management of the Wei River was necessary. Furthermore, this work also indicated that RAPD assay in planarians was a very promising test for environmental monitoring studies.

Genotoxicity evaluation of ionic liquid 1-octyl-3-methylimidazolium bromide in freshwater planarian Dugesia japonica using RAPD assay

The randomly amplified polymorphic DNA (RAPD) assay has been used to detect DNA alternation and mutation recently. However, the effectiveness of this method in detecting DNA damage in planarians, a model organism for assessing the toxicity of environmental pollutants is unknown. In the present study, RAPD assay was used to detect the DNA damage in planarians treated by the ionic liquid 1-octyl-3-methylimidazolium bromide ([C₈mim]Br) for the first time. Among the 20 test RAPD primers, 13 primers with 60-70% GC content produced unique polymorphic band profiles. A total of 60 bands were observed in the untreated control planarians. In comparison with the control group, the [C₈mim]Br-treated groups displayed differences in RAPD patterns in the band intensity, disappearance of normal bands and appearance of new bands. The variation of RAPD profiles showed both concentration- and time-effect relationships. Meanwhile, the genomic template stability (GTS) of treated planarians decreased and exhibited negative correlation to the exposure concentration and time of [C₈mim]Br. Our results suggested that [C₈mim]Br had genotoxic effects on planarians, and this DNA damage analysis would lay the foundation for further elucidating the toxicity mechanisms of ionic liquids on planarians. Furthermore, RAPD analysis was proved to be a highly sensitive method for the detection of DNA damage induced by environmental pollutants like toxic chemicals on planarians.

Psychological intervention for auxiliary treatment of non-erosive reflux disease

Non-erosive reflux disease (NERD) is an independent subtype of gastroesophageal reflux disease, and it is often concomitant with anxiety and/or depression, which seriously influence the patient's quality of life. This article summarizes the research progress of NERD with regard to the pathogenesis of NERD and NERD with anxiety and/or depression, the effect of common treatments on NERD, and psychological intervention for auxiliary treatment of NERD (including establishing a good relationship between doctors and patients, psychological hints, health education, social support and so on). Some deficiencies in the understanding and treatment of NERD are pointed out. In addition, the following suggestions are put forward: more attention should be paid to the psychological factors of patients and psychological intervention should be adopted in the clinical practice and study of NERD; further research should be made on the mechanism of psychological intervention so as to form a unified understanding; epidemiological research and evidence-based medicine research should be carried out to explore the psychological intervention norms on NERD with anxiety and/or depression, in order to improve the curative effect of NERD and the quality of life of patients.

Graphene-clad microfibre saturable absorber for ultrafast fibre lasers

Graphene, whose absorbance is approximately independent of wavelength, allows broadband light–matter interactions with ultrafast responses. The interband optical absorption of graphene can be saturated readily under strong excitation, thereby enabling scientists to exploit the photonic properties of graphene to realize ultrafast lasers. The evanescent field interaction scheme of the propagating light with graphene covered on a D-shaped fibre or microfibre has been employed extensively because of the nonblocking configuration. Obviously, most of the fibre surface is unused in these techniques. Here, we exploit a graphene-clad microfibre (GCM) saturable absorber in a mode-locked fibre laser for the generation of ultrafast pulses. The proposed all-surface technique can guarantee a higher efficiency of light–graphene interactions than the aforementioned techniques. Our GCM-based saturable absorber can generate ultrafast optical pulses within 1.5 μm. This saturable absorber is compatible with current fibre lasers and has many merits such as low saturation intensities, ultrafast recovery times, and wide wavelength ranges. The proposed saturable absorber will pave the way for graphene-based wideband photonics.

Toxic effects of ionic liquid 1-octyl-3-methylimidazolium bromide on the antioxidant defense system of freshwater planarian, Dugesia japonica

The activities of antioxidant enzymes and the levels of glutathione (GSH) and malondialdehyde (MDA) were determined when freshwater planarian Dugesia japonica was exposed to different concentrations of 1-octyl-3-methylimidazolium bromide ([C8mim]Br) for one, three, and five days. The results showed that superoxide dismutase (SOD) activity began to increase in all treated groups after three days of exposure, while catalase (CAT) activity was inhibited after the first day, but increased notably on the fifth day except for the lowest concentration group. The activity of glutathione peroxidase (GPX) was induced from the first day of exposure and increased significantly after five days in all treated groups. During the experiment, the levels of intracellular GSH in all treated groups were higher than that of the control group. Changes in MDA suggest that [C8mim]Br is toxic to D japonica and may result in lipid peroxidation in planarian. Our results also indicate that GPX as well as GSH seem to be more sensitive biomarkers of oxidative stress compared with SOD and CAT.

Albumin and magnetic resonance imaging-liver volume to identify hepatitis B-related cirrhosis and esophageal varices

AIM: To investigate whether liver lobe volume and albumin (ALB) could predict the presence and severity of liver cirrhosis, and esophageal varices.

METHODS: Seventy-one cirrhotic patients with hepatitis B and 21 healthy individuals were enrolled in this study. All the participants underwent abdominal enhanced magnetic resonance imaging to measure each liver lobe volume, and biochemical workup for testing ALB and Child-Pugh class. All cirrhotic patients underwent upper gastrointestinal endoscopy to show the presence of cirrhotic esophageal varices. Right liver lobe volume (RV), left medial liver lobe volume (LMV), left lateral liver lobe volume (LLV), and caudate lobe volume (CV) were measured using enhanced magnetic resonance imaging. The ratios of RV to ALB (RV/ALB), LMV to ALB (LMV/ALB), LLV to ALB (LLV/ALB) and CV to ALB (CV/ALB) were calculated. Statistical analyses were performed to determine whether and how the combination of liver lobe volume measured using magnetic resonance imaging and albumin could predict the presence and severity of liver cirrhosis, and the presence of esophageal varices.

RESULTS: RV, LMV, LLV and CV decreased (r = -0.51-0.373; all P < 0.05), while RV/ALB increased (r = 0.424; P < 0.05), with the progress of Child-Pugh class of liver cirrhosis. RV, LMV, CV, LLV/ALB and CV/ALB could identify presence of liver cirrhosis; LLV and LMV could distinguish Child-Pugh class A from B; RV, LMV, LLV, CV, RV/ALB and LLV/ALB could distinguish class A from C; RV and LLV/ALB could differentiate B from C; and RV, RV/ALB and CV/ALB could identify presence of esophageal varices (all P < 0.05). Among these parameters, CV/ALB could best identify the presence of liver cirrhosis, with an area under receiver operating characteristic curve (AUC) of 0.860, a sensitivity of 82.0% and a specificity of 83.0%. LLV could best distinguish class A from B, with an AUC of 0.761, a sensitivity of 74.4% and a specificity of 73.1%. RV could best distinguish class A from C, with an AUC of 0.900, a sensitivity of 90.3% and a specificity of 84.5%. LLV/ALB could best distinguish class B from C, with an AUC of 0.900, a sensitivity of 93.8% and a specificity of 81.5%. RV/ALB could best identify esophageal varices, with an AUC of 0.890, a sensitivity of 80.0% and a specificity of 83.5%.

CONCLUSION: The combination of liver lobe volume and ALB has potential to identify presence and severity of cirrhosis, and presence of esophageal varices.

[Clinical value of MRI united-sequences examination in diagnosis and differentiation of morphological sub-type of hilar and extrahepatic big bile duct cholangiocarcinoma]

OBJECTIVE

To investigate MRI features and associated histological and pathological changes of hilar and extrahepatic big bile duct cholangiocarcinoma with different morphological sub-types, and its value in differentiating between nodular cholangiocarcinoma (NCC) and intraductal growing cholangiocarcinoma (IDCC).

METHODS

Imaging data of 152 patients with pathologically confirmed hilar and extrahepatic big bile duct cholangiocarcinoma were reviewed, which included 86 periductal infiltrating cholangiocarcinoma (PDCC), 55 NCC, and 11 IDCC. Imaging features of the three morphological sub-types were compared.

RESULTS

Each of the subtypes demonstrated its unique imaging features. Significant differences (P < 0.05) were found between NCC and IDCC in tumor shape, dynamic enhanced pattern, enhancement degree during equilibrium phase, multiplicity or singleness of tumor, changes in wall and lumen of bile duct at the tumor-bearing segment, dilatation of tumor upstream or downstream bile duct, and invasion of adjacent organs.

CONCLUSION

Imaging features reveal tumor growth patterns of hilar and extrahepatic big bile duct cholangiocarcinoma. MRI united-sequences examination can accurately describe those imaging features for differentiation diagnosis.

[Clinical value of dual-source CT angiography in the diagnosis of postoperative aortic intramural hematoma in patients with endovascular stent-graft exclusion surgery]

OBJECTIVE

To determine the clinical value of dual-source CT angiography (DSCTA) in the diagnosis of postoperative aortic intramural hematoma (AIMH) in patients with endovascular stent-graft exclusion (EVE) surgery.

METHODS

Between Oct 2008 and May 2013, thirty-six patients were diagnosed with AIMH by DSCTA, and 12 of these patients with type B underwent EVE. The 12 patients were followed up with DSCTA, which included imaging reconstruction (multi-plane reconstruction, MPR), maximum intensity projection (MIP) and volume rendering technique (VRT). The extent and type of AIMH, aortic ulcers and the outcomes and complications of AIMH were observed.

RESULTS

The 36 cases of AIMH included 11 Stanford type A and 25 type B. No tearing intimal flap or contrast materials within the hematoma were observed. The maximum aortic diameter of the hematoma areas varied from 3.8 to 5.4 cm (average 4.3 cm) and the maximum thickness of the hematoma ranged from 0.5 cm to 1.3 cm (average 0.9 cm). The ratio between the minimum and the maximum diameter of the aortic lumen in the hematoma areas ranged from 0. 74 to 0. 98 (average 0.85). Aortic ulcers were revealed in 3 patients with type A AIMH and 8 patients with type B AIMH. Intimal tearing of distal abdominal aorta was found in 3 patients with type B AIMH. In the 12 patients underwent EVE surgery, hematoma shrank in all cases with 4 cases almost resolving and aortic ulcers in the area of stent-graft exclusion disappeared in 3 cases. The form of stent-graft appeared normal in 9 cases and slightly abnormal in 3 cases. Fluent main branches of aortic arch and none existence of stent endoleaking were observed.

CONCLUSION

DSCTA with handy, effective and non-invasive advantages is one of the important imaging methods in the diagnosis of AIMH in patients with EVE surgery.

Asthma as a hidden disease in rural China: opportunities and challenges of standard case management

OBJECTIVE

To assess the implementation of standard case management of asthma in Huaiyuan County, Anhui Province, China, in 2008.

DESIGN

The study project began with the local adaptation of international asthma guidelines, followed by a situation analysis, pre-intervention study, training and intervention. Inhaled beclomethasone (US$15 for a 200-puff [250 µg/puff] inhaler) was prescribed for patients with persistent asthma. Treatment outcome was assessed at 1 year after enrolment.

RESULTS

Asthma was never diagnosed in the participating facilities before the project was introduced. Of the 95 patients diagnosed with persistent asthma, 72 (75.8%) were prescribed inhaled beclomethasone, and 23 (24.2%) were not, because they either refused to use inhaled beclomethasone or did not return after the initial visit. At 1 year evaluation, of the 72 patients with persistent asthma treated with inhaled corticosteroids, 12 (16.7%) improved, 7 (9.7%) remained stable, none were worse, 1 (1.4%) had died, and 52 (72.2%) were lost to follow-up. Of the 52 patients lost to follow-up, 25 (48%) were found to be alive but had stopped using inhaled beclomethasone.

CONCLUSION

Asthma is more frequently disabling and costly than had been recognised earlier. Asthma patients can be provided the care that they require, but affordable access to inhaled corticosteroids remains a challenge.

Ischemic postconditioning protects cardiomyocytes against ischemia/reperfusion injury by inducing MIP2

Cardiomyocytes can resist ischemia/reperfusion (I/R) injury through ischemic postconditioning (IPoC) which is repetitive ischemia induced during the onset of reperfusion. Myocardial ischemic preconditioning up-regulated protein 2 (MIP2) is a member of the WD-40 family proteins, we previously showed that MIP2 was up-regulated during ischemic preconditioning (IPC). As IPC and IPoC engaged similar molecular mechanisms in cardioprotection, this study aimed to elucidate whether MIP2 was up-regulated during IPoC and contributed to IPoC-mediated protection against I/R injury. The experiment was conducted on two models, an in vivo open chest rat coronary artery occlusion model and an in vitro model with H9c2 myogenic cells. In both models, 3 groups were constituted and randomly designated as the sham, I/R and IPoC/hypoxia postconditioning (HPoC) groups. In the IPoC group, after 45 min of ischemia, hearts were allowed three cycles of reperfusion/ischemia phases (each of 30 s duration) followed by reperfusion. In the HPoC group, after 6 h of hypoxia, H9c2 cells were subjected to three cycles of 10 minute reoxygenation and 10 minute hypoxia followed by reoxygenation. IPoC significantly reduced the infarct size, plasma level of Lactate dehydrogenase and creatine kinase MB in rats. 12 h after the reperfusion, MIP2 mRNA levels in the IPoC group were 10 folds that of the sham group and 1.4 folds that of the I/R group. Increased expression of MIP2 mRNA and attenuation of apoptosis were similarly observed in the HPoC group in the in vitro model. These effects were blunted by transfection with MIP2 siRNA in the H9c2 cells. This study demonstrated that IPoC induced protection was associated with increased expression of MIP2. Both MIP2 overexpression and MIP2 suppression can influence the IPoC induced protection.

Biliary complications in recipients after living donor liver transplantation: influencing factors and imaging manifestations

AIM: To investigate the influencing factors for and imaging manifestations of biliary complications in patients after living donor liver transplantation (LDLT).

METHODS: The imaging data for 119 patients who underwent LDLT at West China Hospital from January 2007 to March 2011 were retrospectively analyzed. All biliary system images were read and analyzed independently by two radiologists.

RESULTS: A total of 119 patients were followed up for 1-18 mo. During the follow-up period, 22 patients developed biliary complications, including 9 cases of cholestasis, 5 cases of cholangitis, 4 cases of stenosis, and 4 cases of bile leakage. Different complications occurred at different time points. Multidetector computed tomography (MDCT) and magnetic resonance imaging (MRI) can display cholestasis, cholangitis and biliary stenosis well, and MRI has greater diagnostic value than MDCT. Both methods had limited value in the diagnosis of bile leakage.

CONCLUSION: The influencing factors for biliary complications in recipients after LDLT are diverse. MDCT and MRI have great value in the detection of these complications.

[Quantification of pancreas fat by MRS and FATSAT with 3.0T MRI]

OBJECTIVE

To test the values of MR spectroscopy (MRS) and fat saturation (FATSAT) in quantifying fat content in pancreas with 3.0T MR.

METHODS

Thirty-five healthy volunteers were examined with 3 different MR techniques IP/OP, MRS, and FATSAT, to quantify pancreas fat content (FC). The IP/OP result served as a reference standard.

RESULTS

The IP/OP, FATSAT and MRS detected (8.2 +/- 2.0)%, (11.8 +/- 4.7)% and (8.8 +/- 4.6)% of pancreas fat content, respectively. The IP/OP result correlated with the MRS result (r = 0.809, P < 0.001), but not with the FATSAT result (r = 0.311, P = 0.069).

CONCLUSION

For 3.0T MRI, MRS technique can quantify pancreas fat content, but FATSAT can not.

Expression patterns and action analysis of genes associated with physiological responses during rat liver regeneration: Innate immune response

AIM: To study the relationship between innate immune response and liver regeneration (LR) at transcriptional level.

METHODS: Genes associated with innate immunity response were obtained by collecting the data from databases and retrieving articles. Gene expression changes in rat regenerating liver were detected by rat genome 230 2.0 array.

RESULTS: A total of 85 genes were found to be associated with LR. The initially and totally expressed number of genes at the phases of initiation [0.5-4 h after partial hepatectomy (PH)], transition from G0 to G1 (4-6 h after PH), cell proliferation (6-66 h after PH), cell differentiation and structure-function reconstruction (66-168 h after PH) was 36, 9, 47, 4 and 36, 26, 78, 50, respectively, illustrating that the associated genes were mainly triggered at the initial phase of LR and worked at different phases. According to their expression similarity, these genes were classified into 5 types: 41 up-regulated, 4 predominantly up-regulated, 26 down-regulated, 6 predominantly down-regulated, and 8 approximately up/down-regulated genes, respectively. The expression of these genes was up-regulated 350 times and down-regulated 129 times respectively, demonstrating that the expression of most genes was enhanced while the expression of a small number of genes was decreased during LR. Their time relevance was classified into 14 groups, showing that the cellular physiological and biochemical activities during LR were staggered. According to the gene expression patterns, they were classified into 28 types, indicating that the cellular physiological and biochemical activities were diverse and complicated during LR.

CONCLUSION: Congenital cellular immunity is enhanced mainly in the forepart, prophase and anaphase of LR while congenital molecular immunity is increased dominantly in the forepart and anaphase of LR. A total of 85 genes associated with LR play an important role in innate immunity.

[Characteristics and expression of Mip5, a novel gene associated with myocardial ischemia/reperfusion in rats]

OBJECTIVE

To determine the characteristics of a novel gene Mip5 (GenBank accession number AY553870) and its expression under physiological and pathological conditions.

METHODS

The characteristics of Mip5 were analyzed by bioinformatic programs including BLAST, spidey, psort, ClustalW and so on. RT-PCR was performed to detect Mip5 expression.

RESULTS

Bioinformatic analysis showed that Mip5 gene lied in the 13th chromosome and contained 8 exons and 7 introns, its open reading frame contained 909 bp and its protein production was 302 amino acid residues including 6 kelth domains. Under normal conditions, MIP5 expressed abundantly in the heart, brain and kidney, but its expression could not be detected in the liver and muscle. Expression of Mip5 gene was increased significantly after ischemia-reperfusion compared with the sham groups, and reached its peak at 3 h and recovered at 12 h after the reperfusion. Conclusion Mip5 gene is a novel gene containing a putative open reading frame of 302 amino acids residues and may play an important role in rat cardiomyocytes suffering ischemia processing.

Diallyl disulfide (DADS) induced apoptosis undergo caspase-3 activity in human bladder cancer T24 cells

Diallyl disulfide (DADS), one of the major components of garlic (Allium sativum), is well known to have chemopreventative activity against human cancer such as colon, lung and skin. But the exact mechanism of the action is still unclear. In this study, we investigated how DADS--induced cell cycle arrest and apoptosis in T24 human bladder cancer cells in vitro. Apoptosis induction, cell viability, cell cycle arrest, caspases-3, -9 activity and gene expression were measured to determine their variation by flow cytometric assay, western blot, and determination of caspase-3 activity, PCR and cDNA microarray. There are significant differences in cell death (decreased viable cells then increased the amounts of apoptosis) of T24 cells that were detected between DADS (5-75 microM) treated and untreated groups. A significant increase was found in apoptosis induction when cells were treated with DADS (50 microM) compared to without DADS treated groups. DADS also promoted caspase-3 activity after exposure for 1, 3, 6, 12, and 24 h, which led to induce apoptosis. DADS also increased the product of intracellular hydrogen peroxide. Furthermore, the DADS-induced apoptosis on T24 cells was blocked by the broad-spectrum caspase inhibitor, z-VAD-fmk and antioxidant (catalase). DADS also increased cyclin E and decreased CDK2 gene expression which may lead to the G2/M arrest of T24 cells.

Effects of garlic components diallyl sulfide and diallyl disulfide on arylamine N-acetyltransferase activity and 2-aminofluorene-DNA adducts in human promyelocytic leukemia cells

Two components of garlic, diallyl sulfide (DAS) and diallyl disulfide (DADS), inhibited arylamine N-acetyltransferase (NAT) activity and 2-aminofluorene-DNA adduct in human promyelocytic leukemia cells (HL-60). The NAT activity was measured by high performance liquid chromatography assaying for amounts of N-acetyl-2-aminofluorene (2-AAF) and remaining 2-aminofluorene (2-AF). Cellular cytosols and intact cell suspensions were assayed. The inhibition of NAT activity and 2-AF-DNA adduct formation in human leukemia cells by DAS and DADS were dose-dependent and were directly proportional. The data also indicated that DAS and DADS decrease the apparent values of Km and Vmax from human leukemia cells in both assays. This is the first report of garlic components affecting human leukemia cell NAT activity and 2-AF-DNA adduct formation.

Novel transmembrane GTPase of non-small cell lung cancer identified by mRNA differential display

The technique of differential display was used previously to profile the gene expression patterns of non-small cell lung cancer, and several genes differentially expressed were thus identified. In this report, we demonstrate that a DNA fragment of 347-bp length, up-regulated in tumor tissues, showed 100% sequence similarity to human cDNA FLJ20693 for a 370-residue protein. The gene product of cDNA FLJ20693 was postulated to be a shorter isoform of transmembrane GTPase, termed TG370, based upon the results of searching for sequence homology. The nucleotide sequence alignment also indicated that the cDNA FLJ20693 and the cDNA for 741-residue human mitofusin 1 (TG741) possibly resulted from the event of alternative splicing from which a 127-bp region was retained in the latter. Analysis of the genome sequence confirmed the speculation that both cDNAs were mapped to the same chromosomal position composing of 18 exons, of which the 127-bp region of TG741 constituted exon 11. The alternative splicing in all lung cancer cell lines was also observed to occur nearly in all tissue specimens examined. The up-regulated expression of transmembrane GTPase was subsequently found in tumor tissues from at least five of seven non-small cell lung cancer patients. Also, a distinct PCR product was initially detected in cell line H520, and further sequence analysis identified the presence of the 86-bp region mapped to the genome sequence immediately followed by exon 10. To evaluate the retention of 86-bp region, it was found that, besides the predicted 486-bp product, an unexpected 332-bp product was concomitantly observed and identified as the result of exon 8 deletion. The expression and subcellular localization of the full-length TG741 and other shorter isoforms were detected by flow cytometry using three polyclonal antibodies. It was concluded that the full-length TG741 located at plasma membrane with its NH(2)-terminal domain exposed extracellularly and the shorter isoforms retained at cytosol. Finally, the up-regulation of transmembrane GTPase in tumor tissues was further illustrated using immunohistochemical staining.

Amantadine-resistant influenza A virus in Taiwan

BACKGROUND AND PURPOSE

Amantadine and rimantadine have been used for treatment and prophylaxis of influenza A virus infection. We examined the amantadine susceptibility of field isolates of influenza A virus in Taiwan from 1996 to 1998 to monitor the presence of resistant strains.

METHODS

Eighty-four field isolates of influenza A virus were examined for resistance to amantadine by plaque inhibition assay. Virus isolates with amantadine 50% inhibitory concentrations (IC50) greater than 0.9 microgram were chosen for sequence analysis of the M gene that is the molecular target for amantadine/rimantadine. Reverse transcription-polymerase chain reaction (RT-PCR) was used to amplify the viral RNA. RT-PCR products were examined and purified by agarose gel electrophoresis for further sequence analysis. The Genetics Computer Group Sequence Analysis Package and the neighbor-joining method listed in the Molecular Evolutionary Genetic Analysis package were used for phylogenetic analysis.

RESULTS

One field strain was amantadine resistant (IC50 > 10 micrograms/mL), with a mutation (position 31, serine to asparagine) in the M2 protein. The resistant virus was isolated from a non-immunocompromised child without a history of amantadine/rimantadine treatment. None of the family members reported previous exposure to amantadine/rimantadine.

CONCLUSIONS

In this series, amantadine-resistant influenza A (H1N1) virus was isolated from a non-immunocompromised Taiwanese child without a known history of exposure to this drug. Resistant field isolates were rare. Due to the increasing use of amantadine/rimantadine in Taiwan, continued surveillance for amantadine/rimantadine-resistant influenza A viruses is warranted.

Luteolin inhibits the growth and arylamine N-acetyl-transferase activity in Neisseria gonorrhoeae

Growth inhibition and arylamine N-acetyltransferase (NAT) activity in Neisseria gonorrhoeae were inhibited by luteolin, a drug which originated from herbs. The growth inhibition was based on changes in optical density (OD) using a spectrophotometer, and arylamine NAT activity with 2-aminofluorene (2-AF) was determined using high pressure liquid chromatography. The inhibition of growth in N. gonorrhoeae demonstrated that luteolin elicited a dose-dependent growth inhibition in the N. gonorrhoeae cultures. Suspensions of N. gonorrhoeae with or without specific concentrations of luteolin cotreatment showed different percentages of 2-AF acetylation. The data indicated that there was reduced NAT activity associated with increased levels of luteolin in N. gonorrhoeae suspensions. Time-course experiments showed that NAT activity measured from intact N. gonorrhoeae cells was inhibited by luteolin for at least 4 h. Using standard steady-state kinetic analysis, it was demonstrated that luteolin was a possible uncompetitive inhibitor to NAT activity in N. gonorrhoeae. This report is the first to show that luteolin can inhibit N. gonorrhoeae NAT activity.

[Clinical and experimental study on treatment of moderate and advanced malignant tumors with tianfoshen oral liquid]

OBJECTIVE

To investigate the clinical efficacy of Tianfoshen oral liquid (TFS) in treating moderate and advanced malignant tumors and its mechanism.

METHODS

Therapeutic effect of TFS in treating 71 patients of malignant tumor was analyzed with the criteria, including quality of life, 3-year survival rate and immune function. And experimental studies of inhibitory effect on tumor clone primordial cells and tumor growth rate of TFS on human gastric tumor (MGC803) cell, human liver cancer (SMMC7721) cell and mice galactophore cancer (EMT6) cell by colony forming method and dye exclusion test respectively were also conducted.

RESULTS

Clinical study showed that in the 71 cases treated, the total remission rate was 45.1%, the effective rate 71.8%, with improvement in quality of life and immune function, the 1-, 2- and 3-year survival rate being 78.5%, 38.5% and 10.8% respectively and the mean survival time 24.2 months. Experimental study showed that TFS could kill the cancer cells directly, inhibit the proliferation of single clonogenic cell, and had a broad-spectrum dose-dependent inhibitory action on various tumors with significant difference in comparing with the effects of the control (P < 0.05).

CONCLUSION

TFS had obvious therapeutic effect to moderate and advanced tumors, its anti-tumor effect was related to the enhancement of immune function and tumor inhibiting or direct killing action.

Effects of the butylated hydroxyanisole and butylated hydroxytoluene on the DNA adduct formation and arylamines N-acetyltransferase activity in human colon tumor cells

The effects of butylated hydroxyanisole (BHA) and butylated hydroxytoluene (BHT) on N-acetyltransferase (NAT) activity were examined using a human colon tumor cell line (colo 205). BHA or BHT were added to the cytosols or to the medium of human colon tumor cells: The NAT activity was measured by high performance liquid chromatography, assaying the amounts of acetylated 2-aminoflluorene (AAF), p aminobenzoic acid (N-Ac-PABA), nonacetylated 2 aminofluorene (AF) and p-aminobenzoic acid (PABA). The NAT activity in the human colon tumor cells and cytosols was suppressed by BHA or BHT in a dose-dependent manner. The apparent values of Km and Vmax of NAT of human colon tumor cells were also decreased by BHA or BHT in cytosols and in intact cells. BHA or BHT may act as a noncompetitive inhibitor. After the incubation of human colon tumor cells with AF in the presence of BHA or BHT, the cells were recovered and DNA was prepared and hydrolysed to nucleotides. Adducted nucleotides were extracted into butanol and AF-DNA adducts were analysed by HPLC. The results also demonstrated that when BHA or BHT was added to the media, a decrease in AF-DNA adduct formation was seen in the human colon tumor cells. The finding of AF-DNA adduct formation in cultured human colon tumor cells suggest the possibility of using cultured cells for assessing arylamine-induced DNA damage.

Effects of berberine on arylamine N-acetyltransferase activity and 2-aminofluorene-DNA adduct formation in human leukemia cells

Berberine is an alkaloid occurring in the plant genera Berberis and Coptis. Although berberine had been demonstrated to have antineoplastic function by inhibiting DNA-synthesis in activated lymphocytes, there is no available information to address berberine affects on human leukemia cell N-acetyltransferase (NAT) activity and 2-aminofluorene (AF)-DNA adduct formation. Thus, berberine was tested for inhibition of arylamine NAT activity and AF-DNA adduct formation in human leukemia cells. The NAT activity was measured by a high performance liquid chromatography assaying for the amounts of N-acetyl-2-aminofluorene (AAF) and N-acetyl-p-aminobenzoic acid (N-Ac-PABA) and the remaining AF and p-aminobenzoic acid (PABA). The NAT activity and AF-DNA adduct formation in human leukemia cells were inhibited by berberine in a dose-dependent manner, i.e. the higher the concentration of berberine, the higher the inhibition of NAT activity and AF-DNA adduct. The data also indicate that berberine decreased the apparent values of Km and Vmax from human leukemia cells in both cytosol and intact cells.