Fusarithioamide B,a new benzamide derivative from the endophytic fungus Fusarium chlamydosporium with potent cytotoxic and antimicrobial activities

Fusarithioamide B (6), a new aminobenzamide derivative with unprecedented carbon skeleton and five known metabolites: stigmast-4-ene-3-one (1), stigmasta-4,6,8(14),22-tetraen-3-one (2), p-hydroxyacetophenone (3), tyrosol (4), and fusarithioamide A (5) were separated from Fusarium chlamydosporium EtOAc extract isolated from Anvillea garcinii (Burm.f.) DC. leaves (Asteraceae). The structure elucidation and complete assignment of the isolated metabolites were performed mainly by the aid of various NMR and MS data. Fusarithioamide B (6) has been assessed for antibacterial and antifungal activities towards various microbial strains by disc diffusion assay. It exhibited selective antifungal activity towards C. albicans (MIC 1.9?µg/ml and IZD 14.5?mm), comparing to clotrimazole (MIC 2.8?µg/ml and IZD 17.9?mm). Also, it possessed high antibacterial potential towards E. coli, B. cereus, and S. aureus compared to ciprofloxacin. Furthermore, 6 was tested for the in vitro cytotoxic effect against KB, HCT-116, BT-549, MCF-7, SKOV-3, and SK-MEL cell lines. It had selective and potent effect towards BT-549, MCF-7, SKOV-3, and HCT-116 cell lines with IC₅₀s 0.09, 0.21, 1.23, and 0.59?μM, respectively compared to doxorubicin (IC₅₀s 0.046, 0.05, 0.321, and 0.24?μM, respectively). Fusarithioamide B may provide a lead molecule for future developing of antitumor and antimicrobial agents.     

The role of AdipoR1 and AdipoR2 in liver fibrosis

Activation of the adiponectin (APN) signaling axis retards liver fibrosis. However, understanding of the role of AdipoR1 and AdipoR2 in mediating this response is still rudimentary. Here, we sought to elucidate the APN receptor responsible for limiting liver fibrosis by employing AdipoR1 and AdipoR2 knock-out mice in the carbon tetrachloride (CCl₄) model of liver fibrosis. In addition, we knocked down receptor function in primary hepatic stellate cells (HSCs) in vitro. Following the development of fibrosis, AdipoR1 and AdipoR2 KO mice had no quantitative difference in fibrosis by Sirius red staining. However, AdipoR2 KO mice had an enhanced fibrotic signature with increased Col1-α1, TGFß-1, TIMP-1, IL-10, MMP-2 and MMP-9. Knockdown of AdipoR1 or AdipoR2 in HSCs followed by APN treatment demonstrated that AdipoR1 and AdipoR2 did not affect proliferation or TIMP-1 gene expression, while AdipoR2 modulated Col1-α1 and α-SMA gene expression, HSC migration, and AMPK activity. These finding suggest that AdipoR2 is the major APN receptor on HSCs responsible for mediating its anti-fibrotic effects.     

Effect of REM sleep on retroglossal cross-sectional area and compliance in normal subjects.

It has been proposed that the upper airway compliance should be highest during rapid eye movement (REM) sleep. Evidence suggests that the increased compliance is secondary to an increased retroglossal compliance. To test this hypothesis, we examined the effect of sleep stage on the relationship of retroglossal cross-sectional area (CSA; visualized with a fiber-optic scope) to pharyngeal pressure measured at the level of the oropharynx during eupneic breathing in subjects without significant sleep-disordered breathing. Breaths during REM sleep were divided into phasic (associated with eye movement, PREM) and tonic (not associated with eye movements, TREM). Retroglossal CSA decreased with non-REM (NREM) sleep and decreased further in PREM [wake 156.8 +/- 48.6 mm(2), NREM 104.6 +/- 65.0 mm(2) (P < 0.05 wake vs. NREM), TREM 83.1 +/- 46.4 mm(2) (P = not significant NREM vs. TREM), PREM 73.9 + 39.2 mm(2) (P < 0.05 TREM vs. PREM)]. Retroglossal compliance, defined as the slope of the regression CSA vs. pharyngeal pressure, was the same between all four conditions (wake -0.7 + 2.1 mm(2)/cmH(2)O, NREM 0.6 +/- 3.0 mm(2)/cmH(2)O, TREM -0.2 +/- 3.3 mm(2)/cmH(2)O, PREM -0.6 +/- 5.1 mm(2)/cmH(2)O, P = not significant). We conclude that the intrinsic properties of the airway wall determine retroglossal compliance independent of changes in the neuromuscular activity associated with changes in sleep state.     

Pollen morphology in Primula sect. Carolinella (Primulaceae) and its taxonomic implications

Pollen morphology in Primula section Carolinella has been investigated for the first time. Seven of the nine species constituting the section were available for study, i. e., P. cardioeides, P. chapaensis, P. intanoensis, P. kwangtungensis, P. kweichouensis, P. partschiana , and P. rugosa, A considerable variation in pollen morphology was found among the investigated species, particularly in number and arrangement of the apertures. Pollen of different species were either tricolpate, tricolporate, trisyncolpate, or polycolpate. Within Primula , the section Carolinella is diagnosed by having calyptrate capsules and leaves with revolute vernation, but the variation in pollen morphology indicates that this group is heterogeneous, and that either polycolpate pollen or a capsular lid has evolved more than once in the genus Primula.     

A comparative evaluation of aflatoxin B1 genotoxicity in fish models using the Comet assay

Aflatoxin B₁ (AFB₁) is classified as a Group I hepatocarcinogen in humans by the International Agency for Research on Cancer (IARC). The alkaline Comet assay is a simple and rapid method by which DNA damage can be demonstrated as a function of tail moment. The present work is the first to evaluate the genotoxicity of AFB₁ in fish using the Comet assay. Two different species of fish were selected as models due to previously established sensitivity to AFB₁: rainbow trout (sensitive) and channel catfish (resistant). Fish were i.p. injected with 0.5 mg AFB₁/1 ml DMSO/1 kg body weight. The Comet assay was performed after 4 and 24 h on whole blood, liver, and kidney cells of both species. Trout blood and kidney tissue tested displayed significant (p<0.05) and extensive DNA damage (shown by increased tail moment) after 4 h which then decreased by 24 h. In liver cells, damage progressively increased over time. Conversely, similarly treated catfish showed no elevation in DNA damage over controls at the same doses. These results suggest that the Comet assay is a useful tool for monitoring the genotoxicity of mycotoxins such as AFB₁ and for evaluating organ specific effects of these agents in different species.     

Insight into the interaction of antitubercular and anticancer compound clofazimine with human serum albumin: spectroscopy and molecular modelling

The binding of clofazimine to human serum albumin (HSA) was investigated by applying optical spectroscopy and molecular docking methods. Fluorescence quenching data revealed that clofazimine binds to protein with binding constant in the order of 10⁴ M^?1, and with the increase in temperature, Stern–Volmer quenching constants gradually decreased indicating quenching mode to be static. The UV–visible spectra showed increase in absorbance upon interaction of HSA with clofazimine which further reveals formation of the drug–albumin complex. Thermodynamic parameters obtained from fluorescence data indicate that the process is exothermic and spontaneous. Forster distance (R_o) obtained from fluorescence resonance energy transfer is found to be 2.05 nm. Clofazimine impelled rise in α-helical structure in HSA as observed from far-UV CD spectra while there are minor alterations in tertiary structure of the protein. Clofazimine interacts strongly with HSA inducing secondary structure in the protein and slight alterations in protein topology as suggested by dynamic light scattering results. Moreover, docking results indicate that clofazimine binds to hydrophobic pocket near to the drug site II in HSA.     

Synthesis of the human insulin gene: protein expression, scaling up and bioactivity

Optimized Synthetic human insulin gene was preferred to easy of cloning, plasmid stability, and protein expression away from the native sequence and its rare codons. Two steps to obtain the insulin, so we assembled the gene of 293 bp using a battery of overlapped synthetic oligos, then cloned into pET101directional TOPO expression vector downstream to the T7 promoter. The proinsulin products were produced as inclusion bodies in E. coli at a level of 10%. The batch cultivation of the strain yielded 6 g/L, while the high cell density of fed-batch cultivation yielded 46 g/L. The proinsulin purification yielded 110 mg/gram cell weight, and 1.3 mg/gram of a bioactive insulin. The native insulin was generated by enzymatic conversion of chemically processed proinsulin. The produced insulin was matched with that of a commercial aqueous version at a level of enzyme immunoassys, SDS-PAGE, RP-HPLC, and bioactivity. The present results showed that the produced insulin has a comparable biochemical and potency similar to that of commercial one.     

A randomized controlled trial to assess the safety and efficacy of silymarin on symptoms,signs and biomarkers of acute hepatitis

PurposeMilk thistle or its purified extract, silymarin (Silybum marianum), is widely used in treating acute or chronic hepatitis. Although silymarin is hepatoprotective in animal experiments and some human hepatotoxic exposures, its efficacy in ameliorating the symptoms of acute clinical hepatitis remains inconclusive. In this study, our purpose was to determine whether silymarin improves symptoms, signs and laboratory test results in patients with acute clinical hepatitis, regardless of etiology.MethodsThis is a randomized, placebo-controlled trial in which participants, treating physicians and data management staff were blinded to treatment group. The study was conducted at two fever hospitals in Tanta and Banha, Egypt where patients with symptoms compatible with acute clinical hepatitis and serum alanine aminotransferase (ALT) levels >2.5 times the upper limit of normal were enrolled. The intervention consisted of three times daily ingestion of either a standard recommended dose of 140 mg of silymarin (Legalon^®, MADAUS GmbH, Cologne, Germany), or a vitamin placebo for four weeks with an additional four-week follow-up. The primary outcomes were symptoms and signs of acute hepatitis and results of liver function tests on days 2, 4 and 7 and weeks 2, 4, and 8. Side-effects and adverse events were ascertained by self-report.ResultsFrom July 2003 through October 2005, 105 eligible patients were enrolled after providing informed consent. No adverse events were noted and both silymarin and placebo were well tolerated. Patients randomized to the silymarin group had quicker resolution of symptoms related to biliary retention: dark urine (p=0.013), jaundice (p=0.02) and scleral icterus (p=0.043). There was a reduction in indirect bilirubin among those assigned to silymarin (p=0.012), but other variables including direct bilirubin, ALT and aspartate aminotransferase (AST) were not significantly reduced.ConclusionsPatients receiving silymarin had earlier improvement in subjective and clinical markers of biliary excretion. Despite a modest sample size and multiple etiologies for acute clinical hepatitis, our results suggest that standard recommended doses of silymarin are safe and may be potentially effective in improving symptoms of acute clinical hepatitis despite lack of a detectable effect on biomarkers of the underlying hepatocellular inflammatory process.