Dynamics of G6PD activity in patients receiving weekly primaquine for therapy of Plasmodium vivax malaria

BackgroundAcute Plasmodium vivax malaria is associated with haemolysis, bone marrow suppression, reticulocytopenia, and post-treatment reticulocytosis leading to haemoglobin recovery. Little is known how malaria affects glucose-6-phosphate dehydrogenase (G6PD) activity and whether changes in activity when patients present may lead qualitative tests, like the fluorescent spot test (FST), to misdiagnose G6PD deficient (G6PDd) patients as G6PD normal (G6PDn). Giving primaquine or tafenoquine to such patients could result in severe haemolysis.MethodsWe investigated the G6PD genotype, G6PD enzyme activity over time and the baseline FST phenotype in Cambodians with acute P. vivax malaria treated with 3-day dihydroartemisinin piperaquine and weekly primaquine, 0·75 mg/kg x8 doses.ResultsOf 75 recruited patients (males 63), aged 5–63 years (median 24), 15 were G6PDd males (14 Viangchan, 1 Canton), 3 were G6PD Viangchan heterozygous females, and 57 were G6PDn; 6 patients had α/β-thalassaemia and 26 had HbE.Median (range) Day0 G6PD activities were 0·85 U/g Hb (0·10–1·36) and 11·4 U/g Hb (6·67–16·78) in G6PDd and G6PDn patients, respectively, rising significantly to 1·45 (0·36–5·54, p<0.01) and 12·0 (8·1–17·4, p = 0.04) U/g Hb on Day7, then falling to ~Day0 values by Day56. Day0 G6PD activity did not correlate (p = 0.28) with the Day0 reticulocyte counts but both correlated over time. The FST diagnosed correctly 17/18 G6PDd patients, misclassifying one heterozygous female as G6PDn.ConclusionsIn Cambodia, acute P. vivax malaria did not elevate G6PD activities in our small sample of G6PDd patients to levels that would result in a false normal qualitative test. Low G6PDd enzyme activity at disease presentation increases upon parasite clearance, parallel to reticulocytosis. More work is needed in G6PDd heterozygous females to ascertain the effect of P. vivax on their G6PD activities.Trial registrationThe trial was registered (ACTRN12613000003774) with the Australia New Zealand Clinical trials (https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=363399&isReview=true).     

Optimization of pretreatment and saccharification for the production of bioethanol from water hyacinth by Saccharomyces cerevisiae

Alkaline-oxidative (A/O) pretreatment and enzymatic saccharification were optimized for bioethanol fermentation from water hyacinth by Saccharomyces cerevisiae. Water hyacinth was subjected to A/O pretreatment at various NaOH and H(2)O(2) concentrations and reaction temperatures for the optimization of bioethanol fermentation by S. cerevisiae. The most effective condition for A/O pretreatment was 7% (w/v) NaOH at 100 °C and 2% (w/v) H(2)O(2). The carbohydrate content was analyzed after reaction at various enzyme concentrations and enzyme ratios using Celluclast 1.5 L and Viscozyme L to determine the effective conditions for enzymatic saccharification. After ethanol fermentation using S. cerevisiae KCTC 7928, the concentration of glucose, ethanol and glycerol was analyzed by HPLC using a RI detector. The yield of ethanol in batch fermentation was 0.35 g ethanol/g biomass. Continuous fermentation was carried out at a dilution rate of 0.11 (per h) and the ethanol productivity was 0.77 [g/(l h)].     

BRCA1 functions independently of homologous recombination in DNA interstrand crosslink repair

Brca1 is required for DNA repair by homologous recombination (HR) and normal embryonic development. Here we report that deletion of the DNA damage response factor 53BP1 overcomes embryonic lethality in Brca1-nullizygous mice and rescues HR deficiency, as measured by hypersensitivity to polyADP-ribose polymerase (PARP) inhibition. However, Brca1,53BP1 double-deficient cells are hypersensitive to DNA interstrand crosslinks (ICLs), indicating that BRCA1 has an additional role in DNA crosslink repair that is distinct from HR. Disruption of the nonhomologous end-joining (NHEJ) factor, Ku, promotes DNA repair in Brca1-deficient cells; however deletion of either Ku or 53BP1 exacerbates genomic instability in cells lacking FANCD2, a mediator of the Fanconi anemia pathway for ICL repair. BRCA1 therefore has two separate roles in ICL repair that can be modulated by manipulating NHEJ, whereas FANCD2 provides a key activity that cannot be bypassed by ablation of 53BP1 or Ku.     

ESM-1 regulates cell growth and metastatic process through activation of NF-κB in colorectal cancer

In our previous study, we reported that endothelial cell specific molecule-1 (ESM-1) was increased in tissue and serum from colorectal cancer patients and suggested that ESM-1 can be used as a potential serum marker for early detection of colorectal cancer. The aim of this study was to evaluate the role of ESM-1 as an intracellular molecule in colorectal cancer. ESM-1 expression was knocked down by small interfering RNA (siRNA) in colorectal cancer cells. Expression of ESM-1 siRNA decreased cell survival through the Akt-dependent inhibition of NF-κB/IκB pathway and an interconnected reduction in phospho-Akt, -p38, -ERK1, -RSK1, -GSK-3α/β and -HSP27, as determined by a phospho-MAPK array. ESM-1 silencing induced G(1) phase cell cycle arrest by induction of PTEN, resulting in the inhibition of cyclin D1 and inhibited cell migration and invasion of COLO205 cells. Consistently, ESM-1 overexpression in HCT-116 cells enhanced cell proliferation through the Akt-dependent activation of NF-κB pathway. In addition, ESM-1 interacted with NF-κB and activated NF-κB promoter. This study demonstrates that ESM-1 is involved in cell survival, cell cycle progression, migration, invasion and EMT during tumor invasion in colorectal cancer. Based on our results, ESM-1 may be a useful therapeutic target for colorectal cancer.     

Synthesis and evaluation of substituted hexahydronaphthalenes as novel inhibitors of the Mcl-1/BimBH3 interaction

Mcl-1, an anti-apoptotic member of the Bcl-2 protein family, is overexpressed in a broad range of human cancers and plays a critical role in conferring resistance to chemotherapy. In the course of screening a natural product-like library of sesquiterpenoid analogs, we identified substituted hexahydronaphthalenes that showed activity against the Mcl-1/BimBH3 interaction in vitro. Here, we describe the synthesis of a small library of analogs and their biological evaluation. The most potent inhibitor in the series (19) exhibits an IC(50) of 8.3μM by ELISA and disrupts the interaction between endogenously expressed Mcl-1 and Bim in cultured MDA-MB-468 breast cancer cells.     

An application of β-glycosidase to transformation of ginsenosides for the effective production of specific ginsenosides with biological efficacy

Over the past several decades, the pharmacological effects of ginsenosides in Panax ginseng roots have been extensively investigated. Here, we developed a method for producing specific ginsenosides (F1 and F2) with good yields (F1:162 mg/g, F2:305 mg/g) using ??-glycosidase purified from Aspergillus niger. In addition, each ginsenoside (at least 25 species) was separated and purified by high performance liquid chromatography (HPLC) using five different types of solvents and different purification steps. In addition, the Rg3:Rh2 mixture (1:1, w/w) was shown to inhibit a specific lung cancer cell line (NCI-H232) in vivo, displaying an anticancer effect at a dose lower than achieved using treatments with single Rg3 or Rh2. This finding suggests that the combination of ginsenosides for targeting anticancer is more effective than the use of a single ginsenoside from ginseng or red ginseng.     

The fanconi anemia pathway limits human papillomavirus replication

High-risk human papillomaviruses (HPVs) deregulate epidermal differentiation and cause anogenital and head and neck squamous cell carcinomas (SCCs). The E7 gene is considered the predominant viral oncogene and drives proliferation and genome instability. While the implementation of routine screens has greatly reduced the incidence of cervical cancers which are almost exclusively HPV positive, the proportion of HPV-positive head and neck SCCs is on the rise. High levels of HPV oncogene expression and genome load are linked to disease progression, but genetic risk factors that regulate oncogene abundance and/or genome amplification remain poorly understood. Fanconi anemia (FA) is a genome instability syndrome characterized at least in part by extreme susceptibility to SCCs. FA results from mutations in one of 15 genes in the FA pathway, whose protein products assemble in the nucleus and play important roles in DNA damage repair. We report here that loss of FA pathway components FANCA and FANCD2 stimulates E7 protein accumulation in human keratinocytes and causes increased epithelial proliferation and basal cell layer expansion in the HPV-positive epidermis. Additionally, FANCD2 loss stimulates HPV genome amplification in differentiating cells, demonstrating that the intact FA pathway functions to restrict the HPV life cycle. These findings raise the possibility that FA genes suppress HPV infection and disease and suggest possible mechanism(s) for reported associations of HPV with an FA cohort in Brazil and for allelic variation of FA genes with HPV persistence in the general population.