Heritability and phenotypic plasticity of biting time behaviors in the major African malaria vector Anopheles arabiensis

Use of Insecticide Treated Nets for malaria control has been associated with shifts in mosquito vector feeding behavior including earlier and outdoor biting on humans. The relative contribution of phenotypic plasticity and heritability to these behavioral shifts is unknown. Elucidation of the mechanisms behind these shifts is crucial for anticipating impacts on vector control. We used a novel portable semi-field system (PSFS) to experimentally measure heritability of biting time in the malaria vector Anopheles arabiensis in Tanzania. In PSFS assays, the biting time of F2 offspring (early: 18:00-21:00, mid: 22:00-04:00 or late: 05:00-07:00) was significantly associated with that of their wild-caught F0 grandmothers, corresponding to an estimated heritability of 0.30 (95% CI: 0.20, 0.41). F2 from early-biting F0 were more likely to bite early than F2 from mid or late late-biting F0. Similarly, the probability of biting late was higher in F2 derived from mid and late-biting F0 than from early-biting F0. Our results indicate that variation in biting time is attributable to additive genetic variation. Selection can therefore act efficiently on mosquito biting times, highlighting the need for control methods that target early and outdoor biting mosquitoes.

Ipsi- and Contralateral Moxibustion Generate Similar Analgesic Effect on Inflammatory Pain

The aim of this study was to investigate whether contralateral moxibustion would generate a similar analgesic effect with ipsilateral moxibustion. Contra- and ipsilateral moxibustion were separately applied to Zusanli (ST36) acupoints of inflammatory pain mice. The analgesic effect was evaluated, respectively, by licking/biting time (LBT) of formalin-induced inflammatory pain and thermal withdrawal latency (TWL) of complete Freund’s adjuvant- (CFA-) induced inflammatory pain. For formalin-induced pain, compared with formalin group, the total LBT of ipsi- and contralateral moxibustion reduced in both phase I and phase II, but there was no significant difference between ipsi- and contralateral moxibustion. For CFA-induced inflammatory pain, compared with CFA group, TWL of ipsi- and contra-Moxi groups increased immediately after moxibustion intervention; however there was no obvious difference between ipsi- and contralateral moxibustion at any timepoint. It indicated that contralateral moxibustion had a similar analgesic effect with ipsilateral moxibustion in both formalin- and CFA-induced pain. These results suggest that both ipsi- and contralateral moxibustion could be applied for pain relief.

Adaptive periodicity in the infectivity of malaria gametocytes to mosquitoes

Daily rhythms in behaviour, physiology and molecular processes are expected to enable organisms to appropriately schedule activities according to consequences of the daily rotation of the Earth. For parasites, this includes capitalizing on periodicity in transmission opportunities and for hosts/vectors, this may select for rhythms in immune defence. We examine rhythms in the density and infectivity of transmission forms (gametocytes) of rodent malaria parasites in the host's blood, parasite development inside mosquito vectors and potential for onwards transmission. Furthermore, we simultaneously test whether mosquitoes exhibit rhythms in susceptibility. We reveal that at night, gametocytes are twice as infective, despite being less numerous in the blood. Enhanced infectiousness at night interacts with mosquito rhythms to increase sporozoite burdens fourfold when mosquitoes feed during their rest phase. Thus, changes in mosquito biting time (owing to bed nets) may render gametocytes less infective, but this is compensated for by the greater mosquito susceptibility.

Torsional Vibration Analysis of Drive System for 6-High Cold Rolling Mill

The torsional vibration model of main drive system for 6-high cold rolling mill was established. Calculation formula of torque amplification factor (TAF) of main drive system was put forward when the clearance exists or not. The TAF-curve, changing by the biting time of blank, was drawn, and whether torsional vibration could cause mechanical failure in weak link of main drive system was judged. The TAF variation with the biting time of blank was analyzed when the clearance exists. The method to reduce TAF was proposed before the clearance was eliminated, and the effect caused by the impact on main drive system was alleviated.

Inhibition of LPS-Induced iNOS, COX-2 and Inflammatory Mediator Expression by Paeonol through the MAPKs Inactivation in RAW 264.7 Cells

We evaluated the in vivo anti-inflammatory and analgesic activities of orally administered paeonol in mice, and also investigated the anti-inflammatory activity of paeonol in a cell line. Paeonol significantly reduced the edema induced by arachidonic acid in rats. The analgesic effects were assayed using 2 different models, i.e., by acetic acid-induced writhing response and by formalin induced licking and biting time. Moreover, we examined the effects of paeonol on the release of inflammatory mediators such as NO , PGE2 and IL-6. Our results demonstrated that paeonol inhibited LPS induced expression of NO , PGE2 and IL-6. Paeonol prevented LPS induced iNOS, COX-2 and ERK activation. Therefore, paeonol appears to have potential as a treatment for inflammatory disease and analgesic.