A long-standing problem of developmental biology is how body size is determined. In Drosophila melanogaster, the insulin ⁄ insulin-like growth factor (I ⁄ IGF) and target of rapamycin (TOR) signaling pathways play important roles in this process. However, the detailed mechanisms by which insect body growth is regulated are not known. Therefore, we have attempted to utilize systemic nymphal RNA interference (nyRNAi) to knockdown expression of insulin signaling components including Insulin receptor (InR), Insulin receptor substrate (chico), Phosphatase and tensin homologue (Pten), Target of rapamycin (Tor), RPS6-p70-protein kinase (S6k), Forkhead box O (FoxO) and Epidermal growth factor receptor (Egfr) and observed the effects on body size in the Gryllus bimaculatus cricket. We found that crickets treated with double-stranded RNA (dsRNA) against Gryllus InR, chico, Tor, S6k and Egfr displayed smaller body sizes, while Gryllus FoxO nyRNAi-ed crickets exhibited larger than normal body sizes. Furthermore, RNAi against Gryllus chico and Tor displayed slow growth and RNAi against Gryllus chico displayed longer lifespan than control crickets. Since no significant difference in ability of food uptake was observed between the Gryllus chico nyRNAi nymphs and controls, we conclude that the adult cricket body size can be altered by knockdown of expressions of Gryllus InR, chico, Tor, S6k, FoxO and Egfr by systemic RNAi. Our results suggest that the cricket is a promising model to study mechanisms underlying controls of body size and life span with RNAi methods.

The following work could bring new insights into the application of heterocyclic N, N′-substituted thiobenzamide derivatives as novel pesticides. Insect growth regulators such as chitin synthesis inhibitors seem promising because of their specific mode of action on insects and their lower toxicity against vertebrates than conventional insecticides. Thus, a novel series of thiobenzamide derivatives have been prepared in a pure state. The structure of these synthesized compounds which related to the most famous insect growth regulator insecticides, were confirmed by elemental and modern spectroscopic analyses (IR, UV, 1HNMR and 13CNMR). Toxicological and biochemical parameters of the synthesized compounds against the cotton leafworm, Spodoptera littoralis under laboratory conditions were also investigated. Regarding the determined LC50 value for compound 2,4-Dichloro-N-[(2-methoxyphenyl)carbamothioyl]- benzamide 14 showed the most potent toxic effects than the other synthetic target compounds, with LC50 46.84 ppm of 2nd instar larvae and LC50 148.05of the 4th instar larvae.

Aims: Depression is a mental health issue that starts most often in early adulthood and it is a common and recurrent disorder causing significant morbidity and mortality worldwide. Amitriptyline is a tricyclic antidepressant that is known to inhibit the presynaptic reuptake of serotonin, norepinephrine, and inhibitor of mitochondrial functions and induces apoptosis in several tissues. This study aims to identify the changes in liver and kidney structure and functions after treatment of male rats with Amitriptyline drugs. Materials and Methods: A total of 20 male albino rats were randomly and equally divided into 2 groups (G1, control group that included animals that did not receive any treatment during the experimental period. G2, Amitriptyline (Tryptizol; El Kahira Pharm And Chem Ind Co) group in which rats were injected intraperitoneally with Amitriptyline (100 mg/kg body weight/daily) for four weeks). Results: The current results revealed that; Amitriptyline treatments significantly (P <0.05) increased the levels of serum ALT, AST, ALP, urea, creatinine, sodium ions, chloride ions and liver  and kidney damages as compared to control. In contrast; a significant (P <0.05) decrease in albumin, and total protein, potassium ions and calcium ions in Amitriptyline group was reported when compared with control group. Conclusion: Amitriptyline has many side effects on rat liver and kidney, it induced liver and kidney toxicity and tissue injury were it metabolized to nortriptyline which inhibits the reuptake of norepinephrine and serotonin almost equally. Amitriptyline inhibits the membrane pump mechanism responsible for uptake of norepinephrine and serotonin in adrenergic and serotonergic neurons.

Resistance against commonly used insecticides is a serious obstacle against eliminating mosquito-borne diseases. There is a demand for novel safe insecticides to control mosquito populations. This study aimed to evaluate the larvicidal action of essential oils extracted from Citrus limon, Myristica fragrans, Citrus sinensis, Syzygium aromaticum, Carumcarvi, Prunusdulcis, Eucalyptus staigeriana, Rosmarinu sofficinalis, Jasminum officinale, and fixed oil extracted from Linum usitatissimum against Culex pipiens 3rd instar larvae. The LC50 value of lemon oil was the lowest and consequently it has been used for subsequent experiments. Lemon oil was characterised using gas chromatography/mass spectrometry (GC/MS), revealing 36 compounds. Treatment with sublethal lemon oil doses significantly reduced fecundity and fertility of the 3rd instar larvae. Transmission electron microscopy revealed histopathological changes in integument layers of lemon oil-treated larvae. The titre of octopamine was increased in 3rd instar larvae. Additionally, lemon oil demonstrated low cytotoxic effects in WI-38 human cells as evaluated. Given the relative non-lethality of lemon oil to non-targets, it is proposed as a promising and environmentally safe alternative to synthetic insecticides for controlling mosquito populations.

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