Linear alcohol ethoxylates: insecticidal and synergistic effects on German cockroaches (Blattodea: Blattellidae) and other insects

Sixteen linear ethoxylated alcohol surfactants (AEOs) were studied to determine their contact insecticidal activity to adult German cockroaches, Blattella germanica (L.) (Blattodea: Blattellidae). Within groups of AEOs of equal carbon chain length, insecticidal activity, measured as LT50 values (in minutes) and 24-h mortality after treatment, was inversely related to the amount of ethoxylation. There was a highly significant negative relationship between the hydrophile-lipophile balance (HLB) value of the AEO and contact toxicity. The AEO with the lowest HLB value, Tomadol 23-1 (HLB = 3.7), produced the greatest 24-h cockroach mortality. The contact activity of Tomadol 23-1 was evaluated against a wide range of other insect species. Most species were killed within 24 h by direct exposure (1-4 microl of a 50% ethanol solution) to Tomadol 23-1 or by spray exposure to an aqueous solution. Tomadol 23-1, at a sublethal concentration, was tested in combination with representative members of the carbamate, nicotinoid, organophosphate, pyrethrum, pyrethroid, and pyrrole insecticide classes. Significant synergism was demonstrated in combinations of Tomadol 23-1 and chlorfenapyr, clothianidin, imidacloprid, thiamethoxam, and pyrethrum. Tomadol 23-1 significantly reduced the insecticidal activity of propoxur, suggesting antagonism. The insecticidal activity of Tomadol 23-1 was synergized by coapplication with a sublethal amount of piperonyl butoxide, indicating the involvement of cytochrome P450 microsomal monooxygenases in insect metabolism of AEO surfactants.     

Labeling of Bifidobacterium longum cells with 13C-substituted leucine for quantitative proteomic analyses

Stable isotope labeling of amino acids in cell culture was used for Bifidobacterium longum. A comprehensive proteomic strategy was developed and validated by designing an appropriate semidefined medium that allows stable replacement of natural leucine by [(13)C6]leucine. Using this strategy, proteins having variations of at least 50% in their expression rates can be quantified with great confidence.     

Complete genome sequence of Bacillus thuringiensis BR145, a strain with insecticidal activity against Lepidoptera pests

Bacillus thuringiensis BR145 isolated from a soybean field in Southern Brazil showed toxicity against two important insect pests from soybean crop, Helicoverpa armigera, and Chrysodeixis includens, with LC₅₀ 0.294 µg.cm^-2 and 0.277 µg.cm^-2, respectively. We analyzed the genome of this strain through sequences obtained by Next Generation DNA Sequencing and de novo assembly. The analysis of the genome revealed insecticidal genes cry1Aa, cry1Ab, cry1Ac, cry1Ia, cry2Ab, cyt1, and vip3Aa, suggesting the use of this strain in new strategies of biological control.     

Healthy Dietary Interventions and Lipoprotein (a) Plasma Levels: Results from the Omni Heart Trial

Background

Increased lipoprotein(a) [Lp(a)] levels are associated with atherosclerotic cardiovascular disease. Studies of dietary interventions on changes in Lp(a) are sparse. We aimed to compare the effects of three healthy dietary interventions differing in macronutrient content on Lp(a) concentration.

Methods

Secondary analysis of a randomized, 3-period crossover feeding study including 155 (89 blacks; 66 whites) individuals. Participants were given DASH-type healthy diets rich in carbohydrates [Carb], in protein [Prot] or in unsaturated fat [Unsat Fat] for 6 weeks each. Plasma Lp(a) concentration was assessed at baseline and after each diet.

Results

Compared to baseline, all interventional diets increased mean Lp(a) by 2 to 5 mg/dl. Unsat Fat increased Lp(a) less than Prot with a difference of 1.0 mg/dl (95% CI, −0.5, 2.5; p = 0.196) in whites and 3.7 mg/dl (95% CI, 2.4, 5.0; p<0.001) in blacks (p-value between races = 0.008); Unsat Fat increased Lp(a) less than Carb with a difference of −0.6 mg/dl, 95% CI, −2.1, 0.9; p = 0.441) in whites and −1.5 mg/dl (95% CI, −0.2, −2.8; p = 0.021) in blacks (p-value between races = 0.354). Prot increased Lp(a) more than Carb with a difference of 0.4 mg/dl (95% CI, −1.1, 1.9; p = 0.597) in whites and 2.2 mg/dl (95%CI, 0.9, 3.5; p = 0.001) in blacks (p-value between races = 0.082).

Conclusion

Diets high in unsaturated fat increased Lp(a) levels less than diets rich in carbohydrate or protein with greater changes in blacks than whites. Our results suggest that substitutions with dietary mono- and polyunsaturated fatty acids in healthy diets may be preferable over protein or carbohydrates with regards to Lp(a).

Trial Registration

Clinicaltrials.gov {"type":"clinical-trial","attrs":{"text":"NCT00051350","term_id":"NCT00051350"}}NCT00051350     

Efficacy of commercial baits and new active ingredients against firebrats and silverfish (Zygentoma: Lepismatidae)

Commercial baits containing boric acid, hydramethynon, and indoxacarb were tested against the firebrat, Thermobia domestica (Packard), and silverfish, Lepisma saccharina L. (both Zygentoma: Lepismatidae), under laboratory conditions. Three boric acid baits were consumed in significantly smaller amounts than untreated control food and did not effectively control either species. Baits containing hydramethylnon and indoxacarb were consumed in greater amounts than boric acid baits, but were relatively ineffective, with LT50 values >9 d. Presence or absence of competitive untreated food did not consistently affect bait efficacy. A ground oat matrix was used to evaluate the potential effectiveness of abamectin, chlorfenapyr, dinotefuran, fipronil, hydramethylnon, metaflumizone, and novaluron baits. The most effective compound was chlorfenapyr. At 0.05 and 0.20% (wt:wt) rates, chlorfenapyr baits produced LT50 values, for both species, ranging from 2 to 4 d. All other compounds had LT50 values >7 d.     

Triply triggered doxorubicin release from supramolecular nanocontainers

The synthesis of a supramolecular double hydrophilic block copolymer (DHBC) held together by cucurbit[8]uril (CB[8]) ternary complexation and its subsequent self-assembly into micelles is described. This system is responsive to multiple external triggers including temperature, pH and the addition of a competitive guest. The supramolecular block copolymer assembly consists of poly(N-isopropylacrylamide) (PNIPAAm) as a thermoresponsive block and poly(dimethylaminoethylmethacrylate) (PDMAEMA) as a pH-responsive block. Moreover, encapsulation and controlled drug release was demonstrated with this system using the chemotherapeutic drug doxorubicin (DOX). This triple stimuli-responsive DHBC micelle system represents an evolution over conventional double stimuli-responsive covalent diblock copolymer systems and displayed a significant reduction in the viability of HeLa cells upon triggered release of DOX from the supramolecular micellar nanocontainers.     

Low-molecular-weight peptide stimulates cholinergic development in ventral spinal cord cultures

Skeletal muscle extract contains a previously undocumented 1300- to 1500-Da neurotrophic factor. Incubation of ventral spinal cord neurons in the presence of this factor enhances the rate of de novo acetylcholine synthesis two- to threefold over control cells, after 6 days in culture. This effect on cholinergic activity appears to be selective, since incubation with the factor results in only slight elevations of lactate dehydrogenase activity and DNA content, and no increase in the acetylcholinesterase activity. The 1300- to 1500-Da factor is acid-stable and partially sensitive to proteolysis by proteinase K, Staphylococcus aureus V8 protease, and subtilisin, but insensitive to trypsin. These results indicate that the active moiety is a peptide. The importance of peptides as neurotransmitters or neuromodulators is well accepted, but their role in the regulation of neuronal development is not widely appreciated. The present cholinergic neurotrophic peptide is distinct from previously characterized cholinergic trophic factors and represents the first example of a small, target-derived peptide which influences cholinergic development.     

Biochemical heterogenity of the left ventricular myocardium: transmural and base-apex gradients on H.E.P. contents of the well oxygenated perfused dog heart.

An investigation into the contents (mumol/g w.w.) of the creatine phosphate (CP) and adenosine triphosphate (ATP) of various myocardial regions was performed on the empty beating isolated blood perfused dog heart. Across the myocardial wall, CP concentration was higher in the outer portion (9.03 +/- 0.18) than in the inner portion (8.59 +/- 0.20) (P less than 0.05). In addition to this transmural gradient, a longitudinal gradient was found: tissue contents of both CP and ATP decrease significantly from the base (CP: 9.70 +/- 0.28, ATP: 5.84 +/- 0.20) to the apex (CP: 8.69 +/- 0.27, ATP: 5.57 +/- 0.17) (P less than 0.01 and P less than 0.05 respectively). The gradients of metabolites in the well oxygenated empty beating heart suggest that a permanent metabolic adaptation to less adequate regional O2 reserves is physiologically operating in the subendocardial layer and the apex region of the left ventricle.