Chicken thalamic injury induced by copper (II) or / and arsenite exposure involves oxidative stress and inflammation-induced apoptosis.

Copper (Cu) is a toxic substance of heavy metals, and arsenic (As) is a toxic substance of metalloids. They all cause oxidative stress and have been widely studied in recent years. Studies have reported that Cu and As can cause inflammation in chicken brain tissue. To assess the toxicological effects of Cu and/or As chronic exposure on chicken thalamus, we used toxicologically relevant concentrations of Cu and As in the chicken diet for 12 weeks. By comparative analysis, we found that higher malondialdehyde (MDA), total antioxidant capacity (T-AOC), and proinflammatory mediator (NF-κB) were observed in the Cu and/or As co-exposed group, indicating that oxidation stress and inflammation are produced. In addition, we also observed mitochondrial kinetics and the generation of apoptosis. These include the gene and protein expression levels of Drp1, Opa1, Mfn1, Mfn2 and Bcl-2, Bax, p53. In conclusion, we believe that in the chronic poisoning of Cu and/or As, inflammation occurs in the chicken thalamus, causing oxidative stress and mitochondrial kinetics, which eventually leads to apoptosis.

Photo-Disassembly of Membrane Microdomains Revives Conventional Antibiotics against MRSA.

Confronted with the rapid evolution and dissemination of antibiotic resistance, there is an urgent need to develop alternative treatment strategies for drug-resistant pathogens. Here, an unconventional approach is presented to restore the susceptibility of methicillin-resistant S. aureus (MRSA) to a broad spectrum of conventional antibiotics via photo-disassembly of functional membrane microdomains. The photo-disassembly of microdomains is based on effective photolysis of staphyloxanthin, the golden carotenoid pigment that gives its name. Upon pulsed laser treatment, cell membranes are found severely disorganized and malfunctioned to defense antibiotics, as unveiled by membrane permeabilization, membrane fluidification, and detachment of membrane protein, PBP2a. Consequently, the photolysis approach increases susceptibility and inhibits development of resistance to a broad spectrum of antibiotics including penicillins, quinolones, tetracyclines, aminoglycosides, lipopeptides, and oxazolidinones. The synergistic therapy, without phototoxicity to the host, is effective in combating MRSA both in vitro and in vivo in a mice skin infection model. Collectively, this endogenous chromophore-targeted phototherapy concept paves a novel platform to revive conventional antibiotics to combat drug-resistant S. aureus infections as well as to screen new lead compounds.

Quantitative imaging of intraerythrocytic hemozoin by transient absorption microscopy.

Hemozoin, the heme detoxification end product in malaria parasites during their growth in the red blood cells (RBCs), serves as an important marker for diagnosis and treatment target of malaria disease. However, the current method for hemozoin-targeted drug screening mainly relies on in vitro ß-hematin inhibition assays, which may lead to false-positive events due to under-representation of the real hemozoin crystal. Quantitative in situ imaging of hemozoin is highly desired for high-throughput screening of antimalarial drugs and for elucidating the mechanisms of antimalarial drugs. We present transient absorption (TA) imaging as a high-speed single-cell analysis platform with chemical selectivity to hemozoin. We first demonstrated that TA microscopy is able to identify ß-hematin, the artificial form of hemozoin, from the RBCs. We further utilized time-resolved TA imaging to in situ discern hemozoin from malaria-infected RBCs with optimized imaging conditions. Finally, we quantitatively analyzed the hemozoin amount in RBCs at different infection stages by single-shot TA imaging. These results highlight the potential of TA imaging for efficient antimalarial drug screening and drug mechanism investigation.

[Identification of endophytic bacteria BZJN1 and research on biological control of root rot of Atractylodes macrocephala].

In this study， an endophytic bacteria strain BZJN1 was isolated from Atractylodes macrocephala， and identified as Bacillus subtilis by physiological and biochemical tests and molecular identification. Strain BZJN1 could inhibit the growth of mycelia of Ceratobasidium sp. significantly， and the inhibition rate was more than 70%. The mycelium growth deformity with bulge as spherical and partially exhaustible in apex or central with microscopic observation. The inhibitory rates under 3% and 6% concentrations of the cell free fermentation were 22.7% and 38.7% expectively. The field test proved that the control efficacy of treatment of 1×108 cfu·mL⁻¹ is 75.27% and 72.37% after 10 and 20 days. All the treatments of strain BZJN1 was able to promote the growth of A. macrocephala， the treatment of 1×108 cfu·mL⁻¹ could able to increase the yield to 14.1%.

Effects of Panax notoginseng saponins on myocardial Gsalpha mRNA expression and ATPase activity after severe scald in rats.

The aim of this study was to investigate the changes of myocardial Gsalpha mRNA expression and ATPase and the effects of Panax notoginseng saponins (PNS) on that after burns in rats. Wistar rats were exposed to a 95 degrees C water bath for 10s to produce 30% TBSA skin-full-thickness scalds. Myocardial Gsalpha mRNA level, cAMP content and adenyl cyclase (AC) activities were determined with dot blotting hybridization, radioimmunoassay and indirect method, respectively. The ATPase activities in plasma membrane of cardiomyocytes and erythrocytes were measured colorimetrically. At 3, 6, 9 hours after scalds, the myocardial Gsalpha mRNA expression decreased significantly (P<0.01). PNS (100, 200 mg kg(-1), i.p.) markedly increased these levels (P<0.01). The elevation was correlated significantly with PNS dose (r=0.95, P<0.05). At 3, 6, 9, 12, 24, 48 hour after the scalds, the myocardial cAMP content and AC basal activity was reduced significantly. PNS (100, 200 mg kg(-1), i.p.) increased cAMP content and enhanced AC activity markedly in comparison with the 3rd hour postburn group. The activities of (Ca(2+)-Mg(2+))-ATPase and (Na(+)-K(+))-ATPase in plasma membrane of myocardial cells and red blood cells in scald group were significantly lower than those in the normal control group (P<0.01). PNS (100 mg kg(-1), i.p.) improved these indexes significantly after scalds (P<0.01 or 0.05). These data suggested that the effects of PNS on myocardium in burned rats involved its action to increase myocardial Gsalpha mRNA expression and AC activity, cAMP content as well as ATPase activities.