The Effects of Acute Exposure to Ammonia on Oxidative Stress, Hematological Parameters, Flesh Quality, and Gill Morphological Changes of the Large Yellow Croaker (Larimichthys crocea).

Ammonia is considered to be the major chemical pollutant causing fish poisoning in aquaculture. This research aimed to evaluate the impact of acute ammonia exposure on the large yellow croaker's meat quality, gill morphology, liver oxidative stress, and hematological parameters. The fish were exposed to total ammonia nitrogen concentrations of 0, 2.96, 5.92, and 8.87 mg/L for 48 h, respectively. The findings demonstrated that all ammonia-exposed fish had higher liver lactate dehydrogenase and glutamic oxalate transaminase activities. The glucose, blood urea nitrogen, and creatinine levels in 8.87 mg/L total ammonia nitrogen (TAN) were higher than other samples. The total protein, albumin, and triglyceride levels in serum decreased significantly in ammonia-exposed samples. After 48 h of ammonia exposure, superoxide dismutase activities showed a 76.1%, 118.0%, and 156.8% increase when fish were exposed to 2.96, 5.92, and 8.87 mg/L TAN, respectively. Catalase activities and glutathione contents were considerably higher (p < 0.05) in all ammonia-treated samples compared to 0 mg/L TAN. The ammonia-treated gill lamellae become thicker, shorter, and curved. Additionally, the ammonia exposure resulted in the accumulation of free amino acids and the loss of nucleotides. The inosine monophosphate and adenosine monophosphate contents in the flesh were decreased after 12 h of exposure to 2.96, 5.92, and 8.87 mg/L ammonia compared to the control group. Overall, large yellow croakers exposed to ammonia for 6 h presented not only changes in serum composition but also oxidative stress, liver and gill tissue damage and flesh quality deterioration.

Analysis of Acute Nitrite Exposure on Physiological Stress Response, Oxidative Stress, Gill Tissue Morphology and Immune Response of Large Yellow Croaker (Larimichthys crocea).

Nitrite is a common pollutant in aquaculture water, and nitrite toxicity that negatively affects aquatic species is common in aquaculture systems when the water quality is low. Therefore, the present research aimed to evaluate the effect of acute nitrite exposure on the hematological parameters, antioxidant enzymes, immune response, and gill morphology of large yellow croaker (Larimichthys crocea). The fish were randomly separated and exposed to four (i.e., 0, 29.36, 58.73, and 88.09 mg/L) nitrite concentrations for 48 h. The fish blood and gills were collected at 0, 12, 24, 36, and 48 h of nitrite exposure for further analysis. In hematological parameters, the results showed that the levels of hemoglobin, triglyceride, and total cholesterol in blood significantly decreased (p < 0.05) in all nitrite-treated samples after 12 h, while the contents of methemoglobin in blood significantly increased (p < 0.05) in these treatments. After 48 h of nitrite exposure, the levels of cortisol in serum showed a 94.5%, 132.1%, and 165.6% increase in fish exposed to 29.36, 58.73, and 88.09 mg/L nitrite, respectively. The nitrite (i.e., 29.36, 58.73, and 88.09 mg/L) exposure significantly increased (p < 0.05) the levels of antioxidant enzymes (i.e., catalase and glutathione) in the gill and serum after 12 h of exposure compared with the control. The lysozyme levels in serum decreased in the nitrite (i.e., 29.36, 58.73, and 88.09 mg/L) exposure samples. It was found that immunoglobulin levels in the 29.36, 58.73, and 88.09 mg/L nitrite-treated samples (i.e., 1.86, 1.58, and 0.74 µg/mL, respectively) were lower than that of the control (2.56 µg/mL). In addition, the surface of the gill lamellae displayed deformation and contraction after 48 h of nitrite, especially in the fish exposed to 88.09 mg/L nitrite. These results indicate that the nitrite exposure induced the oxidative stress, affected the immune response, and changed the gill morphology, leading to nitrite poisoning in large yellow croaker.

Toxic Effects on Bioaccumulation, Hematological Parameters, Oxidative Stress, Immune Responses and Tissue Structure in Fish Exposed to Ammonia Nitrogen: A Review.

Ammonia nitrogen is the major oxygen-consuming pollutant in aquatic environments. Exposure to ammonia nitrogen in the aquatic environment can lead to bioaccumulation in fish, and the ammonia nitrogen concentration is the main determinant of accumulation. In most aquatic environments, fish are at the top of the food chain and are most vulnerable to the toxic effects of high levels of ammonia nitrogen exposure. In fish exposed to toxicants, ammonia-induced toxicity is mainly caused by bioaccumulation in certain tissues. Ammonia nitrogen absorbed in the fish enters the circulatory system and affects hematological properties. Ammonia nitrogen also breaks balance in antioxidant capacity and causes oxidative damage. In addition, ammonia nitrogen affects the immune response and causes neurotoxicity because of the physical and chemical toxicity. Thence, the purpose of this review was to investigate various toxic effects of ammonia nitrogen, including oxidative stress, neurotoxicity and immune response.

Heating behavior using household air-conditioners during the COVID-19 lockdown in Wuhan: An exploratory and comparative study.

Wuhan is located in China's hot summer and cold winter (HSCW) zone, where the average temperature of the city from January to February 2020 is only 6.6 °C. This study aimed to explore and compare the air conditioner (AC) heating behavior of Wuhan residents before and after the COVID-19 lockdown. The date of commencement of the Wuhan lockdown (January 23, 2020) was considered the demarcation point to divide the AC monitoring data from the Internet of Things cloud platform into two groups; before and after Wuhan lockdown. Statistical methods were applied to analyze AC heating behavior of Wuhan residents from a total of 378 air conditioners during these two periods. The daily AC usage rate and average daily AC usage duration following the lockdown had a stronger correlation with daily outdoor temperature than that before the lockdown. AC heating behavior continued to demonstrate a part-time intermittent operation during the lockdown period, despite residents staying at home for a longer period. Trigger temperatures for occupants to turn on or adjust their AC during the lockdown period were overall 1-2 °C higher than before the lockdown. The AC heating demand in the HSCW zone has been increasing in recent years. These research results inform research on household energy demand and thermal comfort in China's HSCW zone, and provide a reference on the household behavioral changes in the occupants in the context of a lockdown as a result of the global COVID-19 pandemic.

[Involvement characteristics and influencing factors of anxiety and depression in patients after percutaneous coronary intervention].

OBJECTIVE: To explore the involvement characteristics and influencing factors of anxiety and depression in patients after percutaneous coronary intervention (PCI). METHODS: A total of 396 patients undergoing PCI were investigated between January 2009 and December 2010. All of them completed the Hospital Anxiety and Depression Scale (HADS) before discharge and at 12 months post-PCI. We evaluated the involvement characteristics and used Logistic regression to analyze the influencing factors of mood changes. RESULTS: The relevant factors of post-PCI anxiety were gender (P = 0.003), age (P = 0.004) and acute myocardial infarction (P = 0.009) while depression was associated with acute myocardial infarction (P < 0.001). A 12-month follow-up study showed that anxiety remained stable in 76.3% of patients while depression in 79.5%. Multi-factor analysis showed that factors of presence of adverse cardiovascular events (OR: 1.323, 95%CI: 1.026 - 1.705, P = 0.031), Seattle angina score (OR: 0.870, 95%CI: 0.772 - 0.981, P = 0.023) and anxiety scores at pre-discharge (OR: 1.228, 95%CI: 1.053 - 1.432, P = 0.009) were correlated with the deterioration degree of depression. And the factor associated with the deterioration of depression was the scores before discharge (OR: 1.287, 95%CI: 1.072 ∼ 1.545, P = 0.007). CONCLUSION: The levels of anxiety and depression remain stable in the majority of PCI patients at Month 12 post-PCI. Perioperative communication and effective control of postoperative cardiovascular events may ease a patient's negative emotions and improve their living quality.