Manipulating Solid Forms of Contact Insecticides for Infectious Disease Prevention.

  title={Manipulating Solid Forms of Contact Insecticides for Infectious Disease Prevention.},
  author={Xiaolong Zhu and Chunhua Tony Hu and Jingxiang Yang and Leo A. Joyce and Mengdi Qiu and Michael D. Ward and Bart Kahr},
  journal={Journal of the American Chemical Society},
Malaria control is under threat by the development of vector resistance to pyrethroids in long-lasting insecticidal nets, which has prompted calls for a return to the notorious crystalline contact insecticide DDT. A faster acting difluoro congener, DFDT, was developed in Germany during World War II, but in 1945 Allied inspectors dismissed its superior performance and reduced toxicity to mammals. It vanished from public health considerations. Herein, we report the discovery of amorphous and… 

A deltamethrin crystal polymorph for more effective malaria control

The simple preparation of form II, coupled with its kinetic stability and markedly higher efficacy, argues that form II can provide a powerful, timely, and affordable malaria control solution for low-income countries that are losing protection in the face of worldwide pyrethroid resistance.

Review and Meta-Analysis of the Evidence for Choosing between Specific Pyrethroids for Programmatic Purposes

In areas where pyrethroid resistance exists, different mortality seen between the pyrethroids is not necessarily indicative of an operationally relevant difference in control performance, and there is no reason to rotate between common pyre Throids as an insecticide resistance management strategy.

Review and Meta-Analysis of the Evidence for Choosing Between Specific Pyrethroids for Programmatic Purposes.

Evidence suggests that in areas where pyrethroid resistance exists, different results in insecticide susceptibility assays with specific pyrethroids currently in common use are not necessarily indicative of an operationally relevant difference in potential performance.

Implications of the Conformationally Flexible, Macrocyclic Structure of the First-Generation, Direct-Acting Anti-Viral Paritaprevir on Its Solid Form Complexity and Chameleonic Behavior.

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Supramolecular architectures sustained by delocalised C–I⋯π(arene) interactions in molecular crystals and the propensity of their formation

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Inverse Correlation between Lethality and Thermodynamic Stability of Contact Insecticide Polymorphs

The efficacy of Forms I, II, and III against Drosophila melanogaster revealed an inverse correlation between lethality and thermodynamic stability; the least stable kills fastest.

Insecticide Resistance After Silent Spring

Combating insecticide resistance is a continual challenge for the preservation of both traditional and transgenic crops, and over the same period, a paradigm shift in dealing with this global problem has also occurred.

Antimalarials inhibit hematin crystallization by unique drug–surface site interactions

It is shown that quinoline-class drugs work by specific interactions with β-hematin crystals, which are the by-product of heme detoxification within the digestive vacuole of the parasites, and the significance of drug–crystal interactions is revealed.

Zika virus evolution and spread in the Americas

It is found that ZIKV circulated undetected in multiple regions for many months before the first locally transmitted cases were confirmed, highlighting the importance of surveillance of viral infections.

The reemergence of yellow fever

It is determined that the outbreak of yellow fever virus originated in northeastern Brazil and moved southward to areas where the virus had not been found previously, which probably explains the magnitude of the outbreak.

DDT Polymorphism and the Lethality of Crystal Forms.

A preliminary study of the contact insecticidal activity toward fruit flies indicates that Form II is more active, suggesting opportunities for more effective solid-state formulations that would allow reduced amounts of DDT, thereby minimizing environmental impact.

Genomic epidemiology reveals multiple introductions of Zika virus into the United States

It is shown that at least 4 introductions, but potentially as many as 40, contributed to the outbreak in Florida and that local transmission is likely to have started in the spring of 2016—several months before its initial detection.

Defining the Determinants of Specificity of Plasmodium Proteasome Inhibitors.

Screening of diverse libraries of non-natural synthetic fluorogenic substrates to identify determinants at multiple positions on the substrate that produce enhanced selectivity finds that selection of an optimal electrophilic "warhead" is essential to enable high selectivity that is driven by the peptide binding elements on the inhibitor.

On the Effect of Synthetic Synergists upon the Knockdown Speed of Pyrethroids against Larvae of the Common House Mosquito, Culex pipiens pallens Coquillett

The results indicated that six synergists studied, except MGK-F5026, decrease the knock-down speed of pyrethrin, allethrin, bartbrin and dimethrin against mosquito larvae.

Crystal nucleation, growth, and morphology of the synthetic malaria pigment beta-hematin and the effect thereon by quinoline additives: the malaria pigment as a target of various antimalarial drugs.

The morphology of micrometer-sized beta-hematin crystals (synthetic malaria pigment) was determined by TEM images and diffraction, and by grazing incidence synchrotron X-ray diffraction at the air-water interface, providing incentive to examine computationally whether hemozoin may be a target of antimalarial drugs diethylamino-alkoxyxanthones and artemisinin.