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Objective To evaluate the effect of low-dose nitroglycerin on oxidative stress and apelin-12 levels in hypertension patients undergoing laparoscopic gynecological surgery. Methods Eighty patients with hypertension who underwent laparoscopic total hysterectomy were recruited and divided into the nitroglycerin group and control group by random number table method. From the beginning of pneumoperitoneum to the end of operation, patients in the nitroglycerin group were pumped with nitroglycerin （0.10-0.25 μg/（kg·min））, and those in the control group were pumped with the same amount of normal saline. Peripheral elbow venous blood was drawn before operation （T0）, 30 min after pneumoperitoneum （T1）, and 1 h after operation （T2）. The changes of serum levels of Ang-Ⅱ, IL-6, apelin-12, and ST-T were compared between two groups. Results With the increase of pneumoperitoneum time, the serum levels of Ang-Ⅱ and IL-6 were gradually elevated, whereas the serum levels of apelin-12 were steadily decreased within each group. Compared with the control group, the increase of serum levels of Ang-Ⅱ and IL-6 at T1 and T2 were significantly decreased and the decrease of serum level of apelin-12 was also significantly decreased in the nitroglycerin group （all P < 0.05）. The incidence of ST-T abnormality had no statistical significance between two groups （P > 0.05）. Conclusions Low-dose nitroglycerin can alleviate the stress response of patients with hypertension undergoing laparoscopic hysterectomy. Apelin-12 may coordinate with NO to delay the incidence and development of oxidative stress.

Survival of the immobile embryo in response to rising temperature is important to determine a species' vulnerability to climate change. However, the collective effects of 2 key thermal characteristics associated with climate change (i.e., rising average temperature and acute heat events) on embryonic survival remain largely unexplored. We used empirical measurements and niche modeling to investigate how chronic and acute heat stress independently and collectively influence the embryonic survival of lizards across latitudes. We collected and bred lizards from 5 latitudes and incubated their eggs across a range of temperatures to quantify population‐specific responses to chronic and acute heat stress. Using an embryonic development model parameterized with measured embryonic heat tolerances, we further identified a collective impact of embryonic chronic and acute heat tolerances on embryonic survival. We also incorporated embryonic chronic and acute heat tolerance in hybrid species distribution models to determine species' range shifts under climate change. Embryos' tolerance of chronic heat (T‐chronic) remained consistent across latitudes, whereas their tolerance of acute heat (T‐acute) was higher at high latitudes than at low latitudes. Tolerance of acute heat exerted a more pronounced influence than tolerance of chronic heat. In species distribution models, climate change led to the most significant habitat loss for each population and species in its low‐latitude distribution. Consequently, habitat for populations across all latitudes will shift toward high latitudes. Our study also highlights the importance of considering embryonic survival under chronic and acute heat stresses to predict species' vulnerability to climate change. [ABSTRACT FROM AUTHOR]

Evaluating the effects of temperature variations on animals plays an important role in understanding the threat of climate warming. The effects of developmental temperature on offspring performance are critical in evaluating the effects of warming temperatures on the fitness of oviparous species, but the physiological and biochemical basis of this developmental plasticity is largely unknown. In this study, we incubated eggs of the turtle Pelodiscus sinensis at low (24 °C), medium (28 °C), and high (32 °C) temperatures, and evaluated the effects of developmental temperature on offspring fitness, and metabolic enzymes in the neck and limb muscles of hatchlings. The hatchlings from eggs incubated at the medium temperature showed better fitness-related performance (righting response and swimming capacity) and higher activities of metabolic enzymes (hexokinase, HK; lactate dehydrogenase, LDH) than hatchlings from the eggs incubated at high or low temperatures. In addition, the swimming speed and righting response were significantly correlated with the HK activities in limb (swimming speed) and neck (righting response) muscles, suggesting that the developmental plasticity of energy metabolic pathway might play a role in determining the way incubation temperature affects offspring phenotypes. Integrating the fitness-related performance and the activities of metabolic enzymes, we predict that the P. sinensis from high latitude would not face the detrimental effects of climate warming until the average nest temperatures reach 32 °C. [ABSTRACT FROM AUTHOR]

Local adaptation is critical in speciation and evolution, yet comprehensive studies on proximate and ultimate causes of local adaptation are generally scarce. Here, we integrated field ecological experiments, genome sequencing, and genetic verification to demonstrate both driving forces and molecular mechanisms governing local adaptation of body coloration in a lizard from the Qinghai-Tibet Plateau. We found dark lizards from the cold meadow population had lower spectrum reflectance but higher melanin contents than light counterparts from the warm dune population. Additionally, the colorations of both dark and light lizards facilitated the camouflage and thermoregulation in their respective microhabitat simultaneously. More importantly, by genome resequencing analysis, we detected a novel mutation in Tyrp1 that underpinned this color adaptation. The allele frequencies at the site of SNP 459# in the gene of Tyrp1 are 22.22% G/C and 77.78% C/C in dark lizards and 100% G/G in light lizards. Model-predicted structure and catalytic activity showed that this mutation increased structure flexibility and catalytic activity in enzyme TYRP1, and thereby facilitated the generation of eumelanin in dark lizards. The function of the mutation in Tyrp1 was further verified by more melanin contents and darker coloration detected in the zebrafish injected with the genotype of Tyrp1 from dark lizards. Therefore, our study demonstrates that a novel mutation of a major melanin-generating gene underpins skin color variation co-selected by camouflage and thermoregulation in a lizard. The resulting strong selection may reinforce adaptive genetic divergence and enable the persistence of adjacent populations with distinct body coloration. [ABSTRACT FROM AUTHOR]

Animals spend a considerable proportion of their life span at rest. However, resting status has often been overlooked when investigating how species respond to environmental conditions. This may induce a large bias in understanding the local adaptation of species across environmental gradients and their vulnerability to potential environmental change. Here, we conducted an empirical study on montane agamid lizards, combined with mechanistic modeling, to compare elevational variations in body temperature and metabolisms (cumulative digestion and maintenance cost) between resting and active status. Our study on three populations of an agamid lizard along an elevational gradient revealed a trend of decreasing body temperature toward higher elevations, the main contributor of which was resting status of the lizards. Using population‐specific reaction norms, we predicted greater elevational variation in hourly and cumulative digestion for resting lizards than for active lizards. Climate‐change impacts, estimated as the change in cumulative digestion, also show greater elevational variation when resting status is factored into the analysis. Further, our global analysis of 98 agamid species revealed that in about half of their combined distributional range, the contribution of resting status in determining the elevational variation in cumulative digestion and maintenance cost of lizards was greater than the contribution made by a lizard's active status. Our study highlights the importance of considering resting status when investigating how species respond to environmental conditions, especially for those distributed over tropical and subtropical mountain areas. [ABSTRACT FROM AUTHOR]