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Objective To investigate the protective effects and underlying mechanisms of sodium butyrate on rats exposed to hypoxia and cold conditions. Methods Fifty-eight male SD rats (aged 7~8 weeks, weighing 240~260 g) were randomly divided into normoxia normothermia saline control (NNC) group (n=10), normoxia normothermia sodium butyrate (NNB) group (n=10), hypoxia cold saline control (HCC) group (n=19), and hypoxia cold sodium butyrate (HCB) group (n=19).The intragastric dose of sodium butyrate was 200 mg/kg for the NNB and HCB groups, while the NNC and HCC groups were given normal saline of 5 mL/kg.①After continuous intragastric administration for 7 d, the rats in the HCC and HCB groups were placed in a low-pressure hypoxic chamber to simulate an altitude of 5 000 m and exposed to a temperature of 8℃ for 7 d.Subsequently, blood samples were collected from the abdominal aorta for blood gas analysis, blood routine test, and detection for serum biochemical indicators.ELISA was used to determine serum inflammatory cytokines and endocrine hormones.The rats in the NNC and NNB groups (n=10) were fed outside the chamber and underwent the same tests in 7 d later to evaluate the protective effects of sodium butyrate on the body.②Core body temperature monitoring was conducted to assess the impact of sodium butyrate on thermoregulation in rats exposed to hypoxia and cold (n=3).③Hypoxia exercise tolerance of the HCC group and HCB group in a hypoxic chamber (11% O2) was evaluated for their hypoxia resistance (n=6). Results Compared to the NNC group, the rats in the HCC group exhibited significant decreases in arterial oxygen saturation (SaO2) and arterial oxygen partial pressure (PaO2), serum levels of IL-4, estradiol (E2) and cortisol (F), core temperature, and exercise duration (P < 0.05), and had notably increased levels of red blood cell (RBC) count, hemoglobin (HGB), hematocrit (HCT), cardiac troponin (CRDAC-T), uric acid (UA), alanine aminotransferase (ALT), total cholesterol (TC), low-density lipoprotein (LDL), IL-6 and granulocyte-macrophage colony-stimulating factor (GM-CSF)(P < 0.05).Compared to the HCC group, the rats in the HCB group exhibited significant increases in SaO2, PaO2, IL-4, E2, F, corticotropin releasing hormone (CRH) and adrenocorticotropic hormone (ACTH)(P < 0.05), remarkably longer exercise duration under hypoxic exposure (P < 0.05), but decreases in RBC count, serum levels of HGB, HCT, CRDAC-T, UA, ALT, TC, LDL, IL-6, GM-CSF and free thyroxine (FT4), and core temperature (P < 0.05). Conclusion Sodium butyrate exhibits protective effects on rats exposed to hypoxia and cold conditions, and it is helpful in their adaptation to these hypoxia and cold environments.

Background Hemorrhagic fever with renal syndrome (HFRS) is a severe acute infectious disease and there are still some control deficiencies according to the epidemic report. Objective To analyze the epidemiological characteristics of HFRS in Guangdong from 2015 to 2021, and explore its impacts by meteorological factors. Methods The HFRS and meteorological data in Guangdong from 2015 to 2021 were collected from the China Disease Prevention and Control Information System and the National Meteorological Science Data Center, respectively. HFRS case information includes the region reported, current address, date of onset, date of death, age, sex and occupation. The population information includes the resident population and sex ratio. Meteorological data includes AP, ARH, AT, MaT, MRH, MiT, PR and SD. SPSS 23.0 was used for descriptive statistical analysis and tested to learn the correlation between HFRS cases and meteorological factors with ARIMA. Results The average annual incidence of HFRS in Guangdong from 2015 to 2020 was 0.23/100, 000, showing a fluctuating downward trend. The confirmed cases of HFRS in Guangdong totalled 1 627 as its fatality rate was 0.18%. The ratio of clinical cases vs confirmed cases was 1∶2.36 (690/1 627) , as the number of cases in Guangzhou, Dongguan and Shenzhen accounted for 63.24% (1 029/1 627) . The temporal-spatial clusterings featured in Guangzhou clustering (38.3%, of which Guangzhou accounted for 75.6%) and Dongguan clustering (61.7%, of which Dongguan accounted for 27.8%) . The incidence peaks were in January and March to May. The sex ratio (male/female) was 3.11∶1 and these coefficient of variations (CV) were 30% and 41%, respectively, the later suggested a greater chance of susceptibility in females. The 25-50 year-old group accounted for 62.75%, where the statistical differences existed among the yearly age-groups (P=0.031) . The occupations included mainly housework and unemployed, business service, labor and farmer, occupied 70.68%. The results included that HFRS cases were significantly correlated with relative humidity (ARH, MRH; Lag4M) , sunshine duration and precipitation (SD, PR; Lag2M) (P

Heavy metal pollution is a serious global environmental issue. It threatens human and ecological health. Heavy metals can accumulate in the soil over extended periods and inevitably transfer through the food chain to herbivorous insects and their natural enemies, leading to various adverse effects. This study aimed to investigate the stress responses and biochemical metabolic changes of aphids and one of aphids' predators, ladybugs, under cadmium (Cd) and lead (Pb) stress by constructing a food chain of Vicia faba L., Megoura crassicauda, and Harmonia axyridis. The results showed that aphids and ladybugs had a notable accumulation of Cd2+ and Pb2+. Insects can adapt to heavy metal stress by regulating their energy metabolism pathways. Glycogen content in the first filial generation (F1) aphids decreased significantly, glucose content in the second filial generation (F2) to the fourth filial generation (F4) adult aphids significantly increased, and trehalose content in the F1 adult aphids increased significantly. Moreover, the relative expression levels of trehalase (TRE) and trehalose-6-phosphate synthase (TPS) in the F1 adult aphids were significantly higher than those in the control group, and the expression levels of TPS genes in the second filial generation to the fifth filial generation (F2 to F5) aphids decreased, suggesting that insects can resist heavy metal stress by regulating trehalose metabolism. The fertility of female aphids in all treatment groups was reduced compared to the control group. Additionally, the relative expression level of vitellogenin (Vg) was down-regulated in all aphid generations except the F1 aphids. There was interaction between heavy metal concentration and aphid generation, and it significantly affected the number of aphids' offspring and the expression of the aphid Vg gene. The developmental duration of the ladybugs from the second to fourth instars was prolonged, and the weight decreased significantly from the prepupa to the adult stages. These results contribute to understanding the effects of Cd2+–Pb2+ accumulation on phytophagous insects and higher trophic levels' natural enemies, laying the foundation for protecting natural enemies and maintaining ecosystem stability. [ABSTRACT FROM AUTHOR]

A well-known insect phenomenon is colour polymorphism, from which the species hopes to gain some ecological advantage. Herbivores adapt to the colours of their environment to reduce their chances of becoming prey, while predators use camouflage colours to succeed in hiding from prey. The larvae of the cosmopolitan, highly invasive cotton bollworm (Helicoverpa armigera Hbn., Lep.: Noctuidae) also benefit from this morphological polymorphism. Their fully- developed larvae can take on various colours when feeding on foliage. Our study aimed to determine the host plant-related colour adaptation of H. armigera larvae collected from different plant organs using different spectral analysis methods. Our studies, based on colour analysis of photographic images, showed that the colour of fully-developed larvae of the species is highly correlated with the colour of the damaged nutrient plant. The dominant colours of the larvae show a high similarity with the colours of the consumed host plant parts. The RGB-based analysis confirmed that larval colours are clustered according to the host plant's organs and are mainly located in the yellow and green regions of the visible light spectrum. All these results confirm the extraordinary adaptive capabilities of this invasive species, which, among other things, verify its worldwide distribution. [ABSTRACT FROM AUTHOR]

In this paper, a surface-enhanced Raman scattering (SERS) spectral probe based on a polymethylmethacrylate (PMMA) polymer fiber is produced by femtosecond laser ablation and photoreduced deposition of silver nanoparticles. It shows that a surface grating structure enabled by femtosecond laser ablation could further improve the SERS signal by around four times larger than the ordinarily roughened structure. By varying femtosecond laser pulse energy and scan surface period in the fabrication process, the enhancement factor of the SERS signal is optimized with laser scan surface period of around 5 μm at 1.2 μJ femtosecond laser pulse energy for a PMMA fiber probe. In particular biochemical analysis, much softer SERS probes are preferred, and our polymer SERS fiber probe shows an alternative method for in situ measurement of the SERS signal and further fabrication of polymer SERS microchip.