Synergistic Effect of Forbesione From Garcinia hanburyi in Combination with 5-Fluorouracil on Cholangiocarcinoma

Background: Chemotherapy for advanced cholangiocarcinoma (CCA) is largely ineffective; thus innovative combinations of chemotherapeutic agents and natural compounds represent a promising strategy. This study aimed to investigate the synergistic effects of forbesione combined with 5-fluorouracil (5-FU) in hamster cholangiocarcinoma (Ham-1) cells both in vitro and in vivo. The anti-tumor effects of 5-FU combined with forbesione in vitro were determined using the Sulforhodamine B (SRB) assay and the effects in vivo were assessed in transplanted Ham-1 allograph models. Using ethidium bromide/acridine orange (EB/AO) staining, the morphological changes of apoptotic cells was investigated. The expressions of apoptosis-related molecules after combined treatment with forbesione and 5-FU were determined using real-time RT-PCR and western blot analysis. Forbesione or 5-FU alone inhibited proliferation of Ham-1 cells in a dose-dependent manner and their combination showed a synergistic proliferation inhibitory effect in vitro. In vivo studies, forbesione in combination with 5-FU exhibited greater inhibition of the tumor in the hamster model compared with treatment using either drug alone. Forbesione combined with 5-FU exerted stronger apoptotic induction in Ham-1 cells than did single drug treatment. The combination of drugs strongly suppressed the expression of B-cell lymphoma 2 (Bcl-2) and procaspase-3 while enhancing the expression of p53, Bcl-2-associated X protein (Bax), apoptotic protease activating factor-1 (Apaf-1), caspase-9 and caspase-3, compared with single drug treatments. These results explained the decreased expression of cytokeratin 19 (CK19) positive cells and proliferation cell nuclear antigen (PCNA) positive cells in Ham-1 cell tumor tissues of the treated hamsters. There was no apparent systemic toxicity observed in the treated animals compared with the control groups. Forbesione combined with 5-FU strongly induced apoptosis in Ham-1 cells. The growth inhibitory effect of combined treatment using these two drugs was much greater than treatment with either drug alone, both in vitro and in vivo.

Characterization of a novel two-component system response regulator involved in biofilm formation and a low-iron response of Burkholderia pseudomallei.

Two-component systems (TCSs) regulate an adaptive response to environmental conditions, leading to changes in bacterial cellular processes. In this study, we identified a novel TCS response regulator gene, designated as bfmR (biofilm formation-associated regulator) that regulates biofilm formation by Burkholderia pseudomallei (Bp). An insertion mutant of the Bp bfmR gene resulted in a significant decrease in expression of fimbriae chaperone-usher assembly genes (BPSL2O28 and BPSL22 7), leading to suppression of assembly of fimbriae on the cell surface and reduced biofilm formation. The defective phenotypes of the mutant strain were restored by introducing a complementing plasmid having an intact bfmR gene. Using RT-PCR analyses, we found that bfmR gene expression was upregulated under low-iron growth conditions. In addition, the bfmR mutant strain showed retarded growth in low-iron medium and in phagocytic cells compared to the wild-type strain. These results indicate that bfmR is a novel positive regulator for controlling assembly of fimbriae and biofilm formation, and is upregulated under low-iron conditions.

Epidemiology and identification of potential fungal pathogens causing invasive fungal infections in a tertiary care hospital in northeast Thailand.

Invasive fungal infections (IFIs) are life threatening and associated with a high mortality rate. Here, we describe the distribution of pathogens, host risk factors, and significance of fungi isolated from patients with IFIs. The study included 861 fungal isolates recovered between 2006 and 2011 from 802 patients at Srinagarind Hospital, Thailand. Based on the European Organization for Research and Treatment of Cancer/Invasive Fungal Infections Cooperative Group and the National Institute of Allergy and Infectious Diseases Mycoses Study Group 2008 criteria, 28.5% (245/861 isolates) of the fungal isolates were considered to be causative agents of IFIs. The most common fungus was Candida albicans (46%, 396/861 isolates). However, the most common yeast causing IFIs was Cryptococcus neoformans (34.7%, 85/245 isolates), while the most common mould was Penicillium marneffei (10.6%, 26/245 isolates). Cryptococcosis was significantly associated with human immunodeficiency virus infections (P < 0.001). Trend analysis revealed that there was no significant increase in IFI cases (P = 0.34) from 2006 to 2011 or from 2007 to 2011 (P = 0.05), but there was a trend toward significant increases in candidiasis (P = 0.04). The fungal isolates were categorized according to the positive predictive value of their recovery in cultures as being true (>95%), moderate (5%-95%), and rare (<5%) pathogens. This classification system could facilitate the prediction of the likelihood of diseases caused by the isolated fungi.

Seroreactivity to specific antigens of Helicobacter pylori infection is associated with an increased risk of the dyspeptic gastrointestinal diseases.

OBJECTIVES: The correlation between seroreactivity to Helicobacter pylori-specific antigens and clinical outcomes in gastrointestinal disease remains unresolved. We investigated the anti-H. pylori antibody profile in northeast Thai dyspeptic patients with gastrointestinal disease in order to identify any H. pylori antigens that may be associated with an increased risk of gastrointestinal disease. PATIENTS AND METHODS: Eighty-nine H. pylori-infected dyspeptic patients (44 non-ulcer, 23 peptic ulcer, 22 gastric cancer) were included in the study. Patients were considered to have H. pylori infection when at least one invasive method (i.e., culture, rapid urease test, and histology on biopsy specimens) and serological tests including a commercial ELISA (Pyloriset EIA-GIII) and a commercial immunoblot (Helicoblot 2.1; Genelabs Diagnostics), were positive. In addition, the sera of 20 H. pylori-infected blood donors and 10 H. pylori-non-infected blood donors were also randomly collected and analyzed for H. pylori infection by ELISA and Helicoblot 2.1. RESULTS: Immunoreactive protein bands at 116-kDa, 89-kDa, 37-kDa, 35-kDa, 30-kDa, 19.5-kDa, and the current infection marker for H. pylori-infected patients had average frequencies of 97.8%, 77.5%, 36.0%, 25.8%, 79.8%, 58.4%, and 69.7%, respectively. The immunoreactive patterns obtained from the H. pylori-infected patients and H. pylori-infected blood donors were similar. The antibodies to VacA and CagA antigens were not significantly different among the H. pylori-infected gastroduodenal patient groups. The simultaneous presence of antibody to 19.5-kDa antigen and absence of antibody to 35-kDa antigen was associated with an increased risk of gastric cancer (p<0.05). The immunoreactive band to 35-kDa antigen was found at significantly higher levels in peptic ulcer patients, and the 37-kDa antigen was found at significantly higher levels in non-ulcer patients (both p<0.05). Significantly low levels of antibodies to 23-kDa and 85-kDa antigens were found associated with peptic ulcer (p<0.05). CONCLUSIONS: We confirm that the universal presence of CagA and VacA in H. pylori-infected patients in Thailand is independent of the gastroduodenal disease. The presence or absence of antibodies to H. pylori-specific antigens may be useful as indirect markers in the screening of H. pylori-infected patients, and may have specific protection roles in H. pylori-related gastroduodenal diseases.

Enzyme-linked immunosorbent assay for serodiagnosis of Helicobacter pylori in dyspeptic patients and volunteer blood donors.

Helicobacter pylori, an important etiological agent in the development of gastritis, peptic ulcer and gastric carcinoma, can be detected by the enzyme-linked immunosorbent assay (ELISA). Our objectives were: (1) to evaluate the efficacy of a commercial ELISA kit (Pyloriset EIA-G III) in sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy for diagnosis of H. pylori infection in Thai dyspeptic patients in Khon Kaen Thailand; and (2) to examine the seroprevalence of H. pylori among blood donors at Srinagarind Hospital's Blood Bank, Khon Kaen University, by the commercial ELISA. Gastric biopsies obtained from 137 dyspeptic patients were diagnosed by culture, rapid urease test (RUT) and histology. Serum samples from the same dyspeptic patients and 100 healthy blood donors were assayed using the commercial ELISA. H. pylori infection in dyspeptic patients was considered positive when the culture or both RUT and histology were positive. Using a cut-off value at a titer of 20 U/ml (as recommended by the manufacturer), we found the commercial ELISA kit had a sensitivity of 93.3%, specificity of 75.3%, PPV of 74.7%, NPV of 93.5% and accuracy of 83.2%. The overall H. pylori seroprevalence in the healthy blood donors was 57%. Of the 100 healthy blood donors, 39 (60.9%) of the males and 18 (50.0%) of the females were seropositive.