Gomisin L1, a Lignan Isolated from Schisandra Berries, Induces Apoptosis by Regulating NADPH Oxidase in Human Ovarian Cancer Cells.

The fruits of Schisandra chinensis (Schisandra berries) are used as health food supplements and popular food ingredients in East Asia. Lignans, major and characteristic polyphenol compounds of Schisandra berries, possess various biological activities, including hepatoprotective and anticancer effects. However, the biological activities of gomisin L1, a lignan isolated from Schisandra berries, are less to be investigated. In this study, the antitumor activity of gomisin L1 and its underlying molecular mechanism in human ovarian cancer cells were investigated. Gomisin L1 exhibited potent cytotoxic activity against A2780 and SKOV3 ovarian cancer cells. Flow cytometry analysis revealed that the growth inhibitory effects of gomisin L1 were mediated by the induction of apoptosis. Furthermore, gomisin L1 induced an increase in intracellular reactive oxygen species (ROS) levels, and the antioxidant N-acetyl cysteine significantly negated gomisin L1-induced cell death. Moreover, inhibition of NADPH oxidase (NOX) using an inhibitor and siRNA attenuated gomisin L1-induced death of, and ROS production in, human ovarian cancer cells. Taken together, these data indicate that the lignan gomisin L1 from Schisandra berries induces apoptotic cell death by regulating intracellular ROS production via NOX.

Effects of Vitamin C or E on the Pro-inflammatory Cytokines, Heat Shock Protein 70 and Antioxidant Status in Broiler Chicks under Summer Conditions.

The present study was carried out to investigate the effects of dietary antioxidants on pro-inflammatory cytokines, heat shock protein (HSP) and antioxidant status in broiler chicks under summer conditions. A total of 162, 3-d-old broiler chicks were randomly assigned to a basal diet (CON) and the basal diet supplemented with vitamin C (200 mg/kg diet, VCD) or vitamin E (100 mg/kg, VED) until 35 day of age. All birds were exposed to summer diurnal heat stress at average daily fluctuations of temperature between 32°C to 34°C at day to 27°C to 29°C at night for the entire feeding periods. There was no significant difference in body weight, feed to gain ratio and the relative organ weight except the thymus in response to dietary vitamin C or E supplementation. However, the mRNA expression of interleukin (IL)-1ß, IL-6, interferon (IFN)-γ, Toll like receptor (TLR)-4 and HSP70 in the liver of birds fed diet containing vitamin C significantly (p<0.05) decreased compared with those in birds fed basal diet. Dietary vitamin E also showed a significant (p<0.05) decrease in the mRNA expression of IL-6 and HSP70 compared with a basal diet. Total antioxidant status (TAS) in serum of birds fed vitamin C supplemented diet was significantly (p<0.05) higher with than that in birds a basal diet. Lipid peroxidation in serum and liver resulted in a significant (p<0.05) decrease in response to dietary vitamin C or E supplementation. In conclusion, dietary supplementation with antioxidant vitamins, especially vitamin C resulted in a significant decrease in the mRNA expression of pro-inflammatory cytokines and HSP70, and higher antioxidant parameters than that of birds on the basal diet under summer conditions.

[Analysis of acquired resistance genes in Stenotrophomonas maltophilia].

BACKGROUND: Stenotrophomonas maltophilia is a gram-negative bacillus and a nosocomial pathogen in immunocompromised patients. Trimethoprim/sulfamethoxazole (TMP/SMX) is the drug of choice for treating S. maltophilia infection; however, resistance to TMP/SMX is increasing. In this study, we investigated the relationship between the incidence of TMP/SMX resistance and the presence of sul genes and mobile elements. METHODS: A total of 120 S. maltophilia isolates were collected from 3 university hospitals between April 2007 and April 2009. Antimicrobial susceptibilities were determined using the disk diffusion method. PCR and DNA sequencing were conducted for the detection of sul1, sul2, class 1 integron, and ISCR2 element. Repetitive extragenic palindromic sequence-based PCR (REP-PCR) was carried out to evaluate the genetic relatedness. RESULTS: The TMP/SMX-resistant (R) isolates harbored a significantly higher proportion of sul1 gene and class 1 integron than TMP/SMX-susceptible (S) isolates (P<0.001). Seventeen of 28 isolates with sul1 also had a class 1 integron, but none of the isolates without sul1 had a class 1 integron. The identified gene cassettes within class 1 integrons include aacA4, aadA1, aac6'-II, and qac. None of the 120 isolates carried sul2, glmM, or ISCR2 element. REP-PCR did not show any genetic relatedness among the isolates. CONCLUSIONS: In Korea, the resistance of S. maltophilia isolates to TMP/SMX is due to sul1 within a class 1 integron rather than to sul2. The class 1 integron also harbors multiple antibiotic resistance genes in addition to sul1, and therefore it could mediate multidrug resistance in S. maltophilia.

Chromosome 8 pentasomy with partial tandem duplication of 11q23 in a case of de novo acute myeloid leukemia.

Polysomy 8 is a rare abnormality, one that has been reported as associated with secondary evolution, monocytic differentiation, or poor prognosis in myeloid neoplasm. In contrast to tetrasomy 8, which is most commonly observed, pentasomy 8 is a minority component of polysomy 8. To date, only three cases of pentasomy 8 accompanied with 11q23 rearrangement have been reported. Reported here is a novel case of pentasomy 8 with partial tandem duplication of 11q23 in de novo acute myeloid leukemia. The findings contribute to understanding of the relation between the two abnormalities, which have their own individual leukemogenic potencies.

Characteristics of aac(6')-Ib-cr gene in extended-spectrum beta-lactamase-producing Escherichia coli and Klebsiella pneumoniae isolated from Chungnam area.

BACKGROUND: Concomitant quinolone resistance in extended-spectrum beta-lactamase (ESBL)-producing Enterobacteriaceae is a crucial problem in the clinical management of infections. In foreign countries, the fluoroquinolone acetylating aminoglycoside-(6)-N-acetyltransferase (aac[6']-Ib-cr) gene, a novel plasmid-mediated quinolone resistance determinant has been reported to occur in conjunction with qnr. We aim to investigate the prevalence and characteristics of concomitant aac(6')-Ib-cr and qnr expression in ESBL-producing Escherichia coli and Klebsiella pneumoniae in Korea. METHODS: Between December 2007 and April 2008, we collected 60 and 69 clonally unrelated non-repetitive clinical isolates of ESBL-producing E. coli and K. pneumoniae, respectively. We studied the expressions of 11 types of ESBL-encoding genes, 4 types of 16s rRNA methylase genes; rmtA, rmtB, rmtC and armA, 3 types of qnr genes; qnrA, qnrB, qnrS and aac(6')-Ib. The presence of aac(6')-Ib-cr variants was detected by sequencing. The involvement of integrons was studied using multiplex PCR and sequencing of gene-cassette arrays. Conjugation experiments were performed to confirm plasmid-mediated resistance and the relationships among co-harbored genes. RESULTS: We observed a high prevalence of the cr variant (61.1%) of aac(6')-Ib, and the prevalence of this variant in qnr and aac(6')-Ib-co-harboring isolates (67.4%) was higher than in qnr-negative isolates (51.7%). The high prevalence of the cr variant was significantly related to the high minimum inhibitory concentrations (MICs) of ciprofloxacin, tobramycin, and amikacin and indicated the statistically significant roles of qnrB, qnrS, rmtA, and rmtB in quinolone and aminoglycoside resistance. CONCLUSIONS: The aac(6')-Ib-cr variants were widespread and showed significant relation to the high-level quinolone and aminoglycoside resistance in ESBL-producing E. coli and K. pneumoniae.