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关键词： PFASs   Siberian tiger   Daily intake   Biochemical parameters  

摘要： Per- and polyfluoroalkyl substances (PFASs) have been ubiquitously detected in the environment and marine animals. However, little is known about these substances and their associations with health parameters in wild terrestrial mammals. In this study, we determined PFAS levels and distribution in the blood of captive Siberian tigers in Harbin, China, and evaluated potential exposure pathways by daily intake. In addition, for the first time, we explored the associations between serum PFAS concentrations and clinical parameters. Results showed that perfluorooctanoate (PFOA) was the dominant PFAS compound in blood (accounting for 64%), followed by perfluorooctanesulfonate (PFOS). In addition, 6:2 chlorinated polyfluorinated ether sulfonate (6:2 CI-PFESA) concentrations were also detected in blood and dietary food. Furthermore, significant positive age relationships were observed for levels of perfluoroheptanoate (PFHpA), PFOA, PFOS, and 6:2 CI-PFESA in the blood of female tigers. Results showed that PFOA and PFOS in dietary food accounted for over 70% of total daily intake of PFASs, indicating that meat consumption is a predominant exposure pathway in tigers. We also found positive associations between higher exposure to PFASs (including PFOA, PFOS, and 6:2 CI-PFESA) and elevated serum levels of alanine transaminase (ALT), a marker of liver damage. Thus, comprehensive health assessments of PFAS burdens in wildlife are needed. (C) 2020 Elsevier Ltd. All rights reserved.

摘要： Fibropapillomatosis (FP) is a tumorforming disease that afflicts all marine turtles and is the most common in green turtles (Chelonia mydas). In this study, the morphometric characteristics, blood gas, biochemistry, and hematological profiles of 28 (6 FP-positive and 22 FP-negative) green turtles from the coast of Taiwan were investigated. The results indicated that body weight (P < 0.001) and curved carapace length (CCL;P < 0.001) in green turtles with FP were significantly higher than in turtles without FP. Furthermore, green turtles with FP had a significantly lower value of hemoglobin (HB;P = 0.010) and packed cell volume (PCV;P = 0.005) than turtles without FP. Blood cell counts of white blood cells (WBC;P = 0.008) and lymphocytes (P = 0.022) were observed with significant difference;green turtles with FP had lower counts than turtles without FP. In addition, turtles with FP had significantly higher pH (P = 0.036), base excess in extracellular fluid (BEecf;P = 0.012), bicarbonate (HCO3-;P = 0.008), and total carbon dioxide (TCO2;P = 0.025) values than turtles without FP. The findings of this study provide valuable clinical parameters for the medical care of the species in sea turtle rehabilitation centers and help us to understand the physiological response of green turtles to different tumor-forming conditions.

关键词： Acid phosphatase activity   Contamination   Dehydrogenase activity   Kunai grass biochar   Soil respiration rate  

摘要： Waste disposal, metal plating, refineries, and mining operations frequently contaminate soils with nickel (Ni). We explored the effects of artificial Ni contamination (0, 56, and 180 mg Ni kg(-1)) on the soil biochemical indices. The lab experiment also investigated the possible use of kunai grass (Imperata cylindrica) biochar at a 0.75% dry weight basis to alleviate contamination effects. The biochemical indices such as dehydrogenase enzyme activity, acid phosphatase enzyme activity, and soil respiration rates were monitored in three replications. High level of Ni (180 mg kg(-1)) suppressed soil respiration rate by 37% and dehydrogenase activity by 62% up to 15 days. The acid phosphatase activity was not affected by Ni levels and was insensitive to Ni contamination. Biochar application to the Ni contaminated soil did not improve the soil's key biological properties. The beneficial effects of biochar could be limited to improvements in soil chemical properties and not on index biological properties.

关键词： Prolactin   Prolactinoma   Cabergoline   Hypogonadism   Dopamine agonist withdrawal  

摘要： Purpose Treatment with dopamine agonists (DA) is highly effective in patients with prolactinomas. In selected patients, discontinuation of DA after several years of successful treatment is possible, however, hyperprolactinemia recurs in 60-80% of them. It is unclear what is the clinical significance of these recurrences and hence, whether or not reinitiation of therapy is necessary. Objectives To evaluate the recurrence rate in prolactinoma patients after DA withdrawal and the necessity to restart treatment. Methods Patients with >2 years of treatment with cabergoline (CBG) who achieved normoprolactinemia anda > 50% reduction in tumor size were included. DA dose was down titrated until withdrawal. Basal tumor size, as well as PRL and gonadal steroid levels were recorded at diagnosis, at withdrawal of DA and every 3-6 months for 1-3 years. Results Fifty patients were included (38 women, 34 macroprolactinomas). After withdrawal, 34 (68%) presented recurrence of hyperprolactinemia. PRL levels <5 ng/mL at the time of withdrawal predicted remission (sensitivity 76%, specificity of 63%). CBG was restarted in eight patients (23%) because of the presence of hypogonadism. CBG was withheld in the remaining 26, based on the following arguments: (1) premenopausal women without biochemical hypogonadism, (54%);(2) asymptomatic men under 65 without biochemical hypogonadism (19%);(3) asymptomatic postmenopausal women (19%);(4) asymptomatic men over 65 (8%). After a median follow-up of 30 months, no increase in PRL levels or tumor growth was documented. Conclusions Biochemical recurrence in prolactinomas is very frequent, however, in only a few of these patients reinitiation of DA is necessary.

关键词： Fibrinolytic enzyme   Bacillus   Cheap substrates   Blood clot   Fibrinolytic agent  

摘要： Objectives: The main aim of this study is to isolate and characterize fibrinolytic enzyme from Bacillus flexus. Methods: Fish meal of Sardinella longiceps and anchovy was optimized using a two-level full factorial design (2(5)) and response surface methodology. The significant physical factors and nutrient sources (peptone, maltose, and magnesium chloride) were identified by statistical approach. The properties of a purified enzyme including their effect at different temperature, pH and the effect of metal ions were evaluated. Results: Enzyme yield was improved 3.5 fold than unoptimized medium. Central composite design optimized culture medium enhanced enzyme yield (4711 +/- 29.3 U/g of substrate). The fibrinolytic enzyme was highly active at alkaline pH (8.0), 50 degrees C and the molecular weight was 32 kDa. Conclusions: From these findings, it concludes that this fibrinolytic enzyme could be a novel potent thrombolytic agent. (C) 2020 The Authors. Published by Elsevier B.V. on behalf of King Saud University.

关键词： Ketone biosynthesis   Hypoglycemia   3-Hydroxy-3-methylglutaryl-CoA   4-Hydroxy-6-methyl-2pyrone   HMGCS2  

摘要： Thirty patients with mitochondrial 3-hydroxy-3-methylglutaryl-CoA synthase (HMGCS) deficiency, which is a rare autosomal recessive disorder caused by HMGCS2 gene mutation are known. Here, we present four new patients with this disease. The characteristics including several metabolites of patients were recorded. Next-generation targeted sequencing and multiple sequence alignment of PCR amplified products allowed for mutational analysis of HMGCS2. Minigene assay transcript analysis confirmed pathogenicity of a splice site mutation. All cases had recurrent episodes with infections while they had no symptoms during intermissions. Patient 1, a girl, showed recurrent severe metabolic acidosis after infections from 8 months old and presented with weakness, vomiting and lethargy but had normal blood glucose. After treatment, she revived completely. Patients 2, 3 and 4 were boys who showed episodes of hypoglycemia since 8, 27 and 10 months of age, respectively. Glucose infusion reversed the symptoms. All four patients had hepatomegaly and abdominal imaging showed fatty livers. Serum free fatty acid increased. Urinary dicarboxylic acids and urinary 4-hydroxy-6-methyl-2pyrone presented. Diagnosis was confirmed by HMGCS2 gene analysis and 7 mutations (p.R188H, p.F420S, p.R206C, IVS2 + 1G > T, p.E401*, p.A450Pfs*7 and p.Q427*) of this gene were found. Here we report on the characteristics and genetics of four new patients with HMGCS deficiency. This study will enrich our knowledge of this rare autosomal recessive disorder.

关键词： Food oral processing   Dietary habits   Salivary alpha-amylase activity   Salivary lipolytic activity  

摘要： Saliva is an important component of food oral processing affecting the initial digestion and the formation of food bolus. It has been speculated that salivary biochemical properties could directly influence one's dietary habits, and vice versa. To date, there are few studies that investigate the possible relationships between dietary habits and salivary biochemical properties in Chinese participants from different dietary background. This study examined two Chinese ethnical groups of very different culture of food consumption, Han and Mongolian healthy young participants, as research participants to explore the differences in salivary biochemical properties and possible associations with dietary preferences. Chinese Mongolians tend to consume more red meat and dairy products, and Chinese Han tend to consume more carbohydrates as suggested by offlcial data;therefore, a total of 304 healthy participants (200 Han and 104 Mongolian) were recruited for salivary compositional analysis. Results showed that for Mongolian participants' unstimulated salivary lipolytic activity (0.10 U/mL) and stimulated salivary lipolytic activity (0.09 U/mL) are significantly higher than those of the Han (0.03 U/mL, 0.04 U/mL) (p < 0.01), but their stimulated salivary alpha-amylase activity (2733 U/mL) was significantly lower than that of Han (3596 U/mL) (p < 0.01). Unstimulated and stimulated salivary total protein content of Chinese Han participants were significantly higher than those of Mongolian participants (p < 0.0001, p = 0.043). These findings have showed our initial hypothesis of possible associations between dietary habits and salivary biochemical properties.

关键词： Heat stress   Pycnogenol   Oxidative stress   Apoptosis   Spermatogenesis  

摘要： Background: Heat stress is a condition that is due to extreme heat exposure. It occurs when the body cannot keep its temperature healthy in response to a hot climate and associated with oxidative stress. Testicular hyperthermia can induce apoptosis of sperm cells, affect sperm production and decrease sperm concentration, leading to sperm disorder, for this reason, we examined the protective impact of pycnogenol that it has a wide range of biological benefits, including antioxidant, anti-inflammatory and anti-cancer activities against the oxidative alterations that happen in testicular and brain tissues due to heat stress in rats. Study design: Forty-eight Wistar male rats, approximately around 6 weeks age were allocated randomly into four groups (12 in each) of control, HS (subjected to heat stress and supplemented orally with 50 mg of pycnogenol/kg b. w./day dissolved in saline for 21 days), and pycnogenol (rats supplemented orally with 50 mg of pycnogenol/kg b. w./day dissolved in saline for 21 days). Results: Data revealed a promising role of pycnogenol as an antioxidant, natural product to successfully reverse the heat-induced oxidative alterations in testicular and brain tissues of rats through significant upregulation of superoxide dismutase-2, catalase, reduced glutathione, and anti-apoptotic gene, while downregulating proapoptotic, and heat shock protein70. Pycnogenol treatment also reversed the reproductive hormone level and spermatogenesis to their normal values. Conclusion: Pycnogenol as a natural protective supplement could recover these heat stress-induced oxidative changes in testes and hypothalamus.

关键词： carbohydrate-to-lipid ratios   Epinephelus coioides   growth performance   intestinal digestive enzymes   liver immune enzymes   plasma biochemical indicators  

摘要： An 8-week feeding trial was conducted to investigate the effects of dietary carbohydrate-to-lipid (CHO:L) ratios on growth, liver and muscle glycogen content, haematological indices, and liver and intestinal enzyme activity of juvenile grouper (Epinephelus coioides). Five isonitrogenous (496.0 g/kg protein) and isoenergetic (21.6 KJ/g gross energy) diets with varying CHO:L ratios of 0.65 (D1), 1.31 (D2), 2.33 (D3), 4.24 (D4) and 8.51 (D5), respectively, were fed to triplicate groups of 20 fish (average 10.02 +/- 0.1 g) for 8 weeks. Results showed that the weight gain rate, specific growth rate and protein efficiency ratio (PER) of juvenile grouper increased first and then decreased with the increase in CHO:L ratio, reaching a maximum value in the D4 (CHO:L = 4.24) diet. The trend for the feed conversion ratio was opposite to the PER. Along with the diet CHO:L ratios, the apparent digestibility coefficients (ADC) of crude lipid and energy for the juvenile groupers decreased gradually, while the ADC of dry matter, liver and muscle glycogen level increased gradually. Total protein, triglycerides and cholesterol in serum were all maximized in the D4 diet and glucose in the D5 (CHO:L = 8.51) diet. Digestive enzyme activity in the intestine was significantly affected by dietary CHO:L ratio. Liver hexokinase, phosphofructokinase and glucose-6-phosphate dehydrogenase activity increased significantly as CHO:L ratio increased. Liver lysozyme and acid phosphatase activity in the groupers fed the D3 (CHO:L = 2.33) diet was significantly higher than that of other diets. Liver fructose-1,6-bisphosphatase and alkaline phosphatase activity reached a maximum value in the D4 diet and was significantly higher than that in the D1 diet. Taking the above results together, it can be concluded that an optimal dietary CHO:L ratio of 2.33 is suitable for grouper culture concerning growth performance and health.

关键词： Seaweeds   Biorefinery   Biochemical composition   Water content   Metals  

摘要： Seaweed biomass has the potential to become an important raw material for bio-based production. The aim of this study was to screen the overall composition of several seaweed species on the Swedish west coast, including some scarcely studied species, to provide fundamentals for evaluation of biorefining potential and to benchmark with already potentially industrially relevant species and commercially important land-based biomasses. Twenty-two common seaweed species (green, red, brown) were collected and the carbohydrate, ash, protein, water and metal contents were measured. Carbohydrate content varied between 237 and 557 g kg(-1) dry weight (dw), making it the largest constituent, on a dry weight basis, of most species in the study. Ash, which is considered unwanted in biorefining, ranged between 118 and 419 g kg(-1) dw and was the largest constituent in several seaweeds, which were therefore considered unsuitable for biorefining. Protein content was most abundant in the red seaweeds but was generally low in all species (59-201 g kg(-1) dw). High contents of several unwanted metals for processing or human consumption were found (e.g. aluminium, arsenic, copper, chromium and nickel), which need to be considered when utilizing seaweeds for certain applications. Potential targets for further biorefinery development mostly include species already known for their potential (Saccharina latissima, Laminaria digitata and Chondrus crispus) while some, such as Halidrys siliquosa and Dilsea carnosa, have not been previously noted. However, more detailed studies are required to explore biorefinery processes for these seaweeds, as well as how to potentially cultivate them.