The intrinsic and extrinsic elements regulating inflammation.

Inflammation is a sophisticated biological tissue response to both extrinsic and intrinsic stimuli. Although the pathological aspects of inflammation are well appreciated, there are still rooms for understanding the physiological functions of the inflammation. Recent studies have focused on mechanisms, context and the role of physiological inflammation. Besides, there have been progress in the comprehension of commensal microbiota, immunometabolism, cancer and intracellular signaling events' roles that impact on the regulation of inflammation. Despite the fact that inflammatory responses are vital through tissue damage, understanding the mechanisms to turn off the finished or unnecessary inflammation is crucial for restoring homeostasis. Inflammation seems to be a smart process that acts like two edges of a sword, meaning that it has both protective and deleterious consequences. Knowing both edges and the regulation processes will help the future understanding and therapy for various diseases.

Physiology of Hibernating Larvae of the Pistachio Twig Borer, Kermania pistaciella Amsel (Lepidoptera: Tineidae), Collected from Akbari Cultivar of Pistacia vera L.

The pistachio twig borer, Kermania pistaciella Amsel (Lepidoptera: Tineidae), a key pest of pistachio trees, is a monovoltine pest living inside the feeding tunnel of pistachio twigs for almost 10 months in a year and overwinters there as last instar larvae. In this study, we measured some physiological parameters of overwintering field collected larvae of the pest. There were no changes in trehalose, glucose, and myo-inositol contents, but there were differences in the levels of total simple sugar and glycogen during overwintering. Total sugar content at the beginning of overwintering (October) was at the lowest level (24.13 mg/g body weight) and reached to the highest level (55.22 mg/g fresh body weight) in November whereas glycogen content was at the highest level (44.05 mg/g fresh body weight) in October and decreased to 18.42 mg/g fresh body weight in November. Decrease in lipid content during the overwintering period was not significant. The highest and lowest levels of protein content were recorded in January and February, respectively. Supercooling points (SCP) of the overwintering larvae were stable and low (ranged between -17.80 and -25.10°C) throughout the cold season and no larva survived after SCP determination. The lowest cold hardiness (60 and 0.0% survival following exposure to -10 and -20°C/24 h, respectively) was observed for in November-collected larvae. Overwintering larvae of the pistachio twig borer rely mostly on maintaining the high supercooling capacity throughout the overwintering to avoid freezing of their body fluid.

Overwintering biology and limits of cold tolerance in larvae of pistachio twig borer, Kermania pistaciella.

Pistachio twig borer, Kermania pistaciella is an important pest of pistachio trees. It has an univoltine life-cycle and its larvae tunnel and feed inside pistachio twigs for almost 10 months each year. The last larval instars overwinter inside the twigs. Survival/mortality associated with low temperatures during overwintering stage is currently unknown. We found that overwintering larvae of the Rafsanjan (Iran) population of K. pistaciella rely on maintaining a stably high supercooling capacity throughout the cold season. Their supercooling points (SCPs) ranged between -19.4 and -22.7°C from October to February. Larvae were able to survive 24 h exposures to -15°C anytime during the cold season. During December and January, larvae were undergoing quiescence type of dormancy caused probably by low ambient temperatures and/or changes in host tree physiology (tree dormancy). Larvae attain highest cold tolerance (high survival at -20°C) during dormancy, which offers them sufficient protection against geographically and ecologically relevant cold spells. High cold tolerance during dormancy was not associated with accumulation of any low-molecular mass cryoprotective substances. The SCP sets the limit of cold tolerance in pistachio twig borer, meaning that high mortality of overwintering populations can be expected only in the regions or years where or when the temperatures fall below the average larval SCP (i.e., below -20°C). Partial mortality can be expected also when temperatures repeatedly drop close to the SCP on a diurnal basis.