Broodstock nutritional programming differentially affects the hepatic transcriptome and genome-wide DNA methylome of farmed gilthead sea bream (Sparus aurata) depending on genetic background

BACKGROUND

Broodstock nutritional programming improves the offspring utilization of plant-based diets in gilthead sea bream through changes in hepatic metabolism. Attention was initially focused on fatty acid desaturases, but it can involve a wide range of processes that remain largely unexplored. How all this can be driven by a different genetic background is hardly underlined, and the present study aimed to assess how broodstock nutrition affects differentially the transcriptome and genome-wide DNA methylome of reference and genetically selected fish within the PROGENSA® selection program.

RESULTS

After the stimulus phase with a low fish oil diet, two offspring subsets of each genetic background received a control or a FUTURE-based diet. This highlighted a different hepatic transcriptome (RNA-seq) and genome-wide DNA methylation (MBD-seq) pattern depending on the genetic background. The number of differentially expressed transcripts following the challenge phase varied from 323 in reference fish to 2,009 in genetically selected fish. The number of discriminant transcripts, and associated enriched functions, were also markedly higher in selected fish. Moreover, correlation analysis depicted a hyper-methylated and down-regulated gene expression state in selected fish with the FUTURE diet, whereas the opposite pattern appeared in reference fish. After filtering for highly represented functions in selected fish, 115 epigenetic markers were retrieved in this group. Among them, lipid metabolism genes (23) were the most reactive following ordering by fold-change in expression, rendering a final list of 10 top markers with a key role on hepatic lipogenesis and fatty acid metabolism (cd36, pitpna, cidea, fasn, g6pd, lipt1, scd1a, acsbg2, acsl14, acsbg2).

CONCLUSIONS

Gene expression profiles and methylation signatures were dependent on genetic background in our experimental model. Such assumption affected the magnitude, but also the type and direction of change. Thus, the resulting epigenetic clock of reference fish might depict an older phenotype with a lower methylation for the epigenetically responsive genes with a negative methylation-expression pattern. Therefore, epigenetic markers will be specific of each genetic lineage, serving the broodstock programming in our selected fish to prevent and mitigate later in life the risk of hepatic steatosis through changes in hepatic lipogenesis and fatty acid metabolism.

Temperature variation in nests of Paleosuchus palpebrosus (Crocodylia: Alligatoridae) near the southern edge of the species´ range, Brazil

Abstract We monitored the temperature of seven Paleosuchus palpebrosus nests found on the banks of streams surrounding the Brazilian Pantanal, near the southern limit of the species´ distribution, between 2008 and 2013. The mean temperature of the nests between 45 and 68 days incubation, the presumed period of sex determination, varied between 26.1 and 31.5o C. Nest temperatures were 2 to 5°C higher than air temperatures, presumably due to metabolic heat of decay of material within the nests, but air temperature explained 10–50% of the variance in egg-chamber temperatures. The estimated incubation periods for nests from which eggs hatched were 80, 84, 86, 90 and 104 days with a mean of 89 (SD =9.23) days, though these are probably slight overestimates because eggs may have hatched in the period between inspections. For these nests, there was no significant relationship between mean temperature and incubation period (r2 = 0.23, p = 0.411).

Impact of Covid-19 on farming systems in Europe through the lens of resilience thinking

CONTEXT

Resilience is the ability to deal with shocks and stresses, including the unknown and previously unimaginable, such as the Covid-19 crisis.

OBJECTIVE

This paper assesses (i) how different farming systems were exposed to the crisis, (ii) which resilience capacities were revealed and (iii) how resilience was enabled or constrained by the farming systems' social and institutional environment.

METHODS

The 11 farming systems included have been analysed since 2017. This allows a comparison of pre-Covid-19 findings and the Covid-19 crisis. Pre-Covid findings are from the SURE-Farm systematic sustainability and resilience assessment. For Covid-19 a special data collection was carried out during the early stage of lockdowns.

RESULTS AND CONCLUSIONS

Our case studies found limited impact of Covid-19 on the production and delivery of food and other agricultural products. This was due to either little exposure or the agile activation of robustness capacities of the farming systems in combination with an enabling institutional environment. Revealed capacities were mainly based on already existing connectedness among farmers and more broadly in value chains. Across cases, the experience of the crisis triggered reflexivity about the operation of the farming systems. Recurring topics were the need for shorter chains, more fairness towards farmers, and less dependence on migrant workers. However, actors in the farming systems and the enabling environment generally focused on the immediate issues and gave little real consideration to long-term implications and challenges. Hence, adaptive or transformative capacities were much less on display than coping capacities. The comparison with pre-Covid findings mostly showed similarities. If challenges, such as shortage of labour, already loomed before, they persisted during the crisis. Furthermore, the eminent role of resilience attributes was confirmed. In cases with high connectedness and diversity we found that these system characteristics contributed significantly to dealing with the crisis. Also the focus on coping capacities was already visible before the crisis. We are not sure yet whether the focus on short-term robustness just reflects the higher visibility and urgency of shocks compared to slow processes that undermine or threaten important system functions, or whether they betray an imbalance in resilience capacities at the expense of adaptability and transformability.

SIGNIFICANCE

Our analysis indicates that if transformations are required, e.g. to respond to concerns about transnational value chains and future pandemics from zoonosis, the transformative capacity of many farming systems needs to be actively enhanced through an enabling environment.

Generalized Structure Functions and Multifractal Detrended Fluctuation Analysis Applied to Vegetation Index Time Series: An Arid Rangeland Study

Estimates suggest that more than 70% of the world’s rangelands are degraded. The Normalized Difference Vegetation Index (NDVI) is commonly used by ecologists and agriculturalists to monitor vegetation and contribute to more sustainable rangeland management. This paper aims to explore the scaling character of NDVI and NDVI anomaly (NDVIa) time series by applying three fractal analyses: generalized structure function (GSF), multifractal detrended fluctuation analysis (MF-DFA), and Hurst index (HI). The study was conducted in four study areas in Southeastern Spain. Results suggest a multifractal character influenced by different land uses and spatial diversity. MF-DFA indicated an antipersistent character in study areas, while GSF and HI results indicated a persistent character. Different behaviors of generalized Hurst and scaling exponents were found between herbaceous and tree dominated areas. MF-DFA and surrogate and shuffle series allow us to study multifractal sources, reflecting the importance of long-range correlations in these areas. Two types of long-range correlation appear to be in place due to short-term memory reflecting seasonality and longer-term memory based on a time scale of a year or longer. The comparison of these series also provides us with a differentiating profile to distinguish among our four study areas that can improve land use and risk management in arid rangelands.

Functional insights into the infective larval stage of Anisakis simplex s.s., Anisakis pegreffii and their hybrids based on gene expression patterns

BACKGROUND

Anisakis simplex sensu stricto and Anisakis pegreffii are sibling species of nematodes parasitic on marine mammals. Zoonotic human infection with third stage infective larvae causes anisakiasis, a debilitating and potentially fatal disease. These 2 species show evidence of hybridisation in geographical areas where they are sympatric. How the species and their hybrids differ is still poorly understood.

RESULTS

Third stage larvae of Anisakis simplex s.s., Anisakis pegreffii and hybrids were sampled from Merluccius merluccius (Teleosti) hosts captured in waters of the FAO 27 geographical area. Specimens of each species and hybrids were distinguished with a diagnostic genetic marker (ITS). RNA was extracted from pools of 10 individuals of each taxon. Transcriptomes were generated using Illumina RNA-Seq, and assembled de novo. A joint assembly (here called merged transcriptome) of all 3 samples was also generated. The inferred transcript sets were functionally annotated and compared globally and also on subsets of secreted proteins and putative allergen families. While intermediary metabolism appeared to be typical for nematodes in the 3 evaluated taxa, their transcriptomes present strong levels of differential expression and enrichment, mainly of transcripts related to metabolic pathways and gene ontologies associated to energy metabolism and other pathways, with significant presence of excreted/secreted proteins, most of them allergens. The allergome of the 2 species and their hybrids has also been thoroughly studied; at least 74 different allergen families were identified in the transcriptomes.

CONCLUSIONS

A. simplex s.s., A. pegreffi and their hybrids differ in gene expression patterns in the L3 stage. Strong parent-of-origin effects were observed: A. pegreffi alleles dominate in the expression patterns of hybrids albeit the latter, and A. pegreffii also display significant differences indicating that hybrids are intermediate biological entities among their parental species, and thus of outstanding interest in the study of speciation in nematodes. Analyses of differential expression based on genes coding for secreted proteins suggests that co-infections presents different repertoires of released protein to the host environment. Both species and their hybrids, share more allergen genes than previously thought and are likely to induce overlapping disease responses.

Dynamic intracoronary thrombosis does not cause significant downstream platelet embolization

OBJECTIVE

A mural intracoronary thrombus is a potential source of platelet emboli that may obstruct downstream microvessels, but this phenomenon has not been characterized. The present study aimed to assess the magnitude of myocardial platelet accumulation downstream of a mural intracoronary thrombus and its modification by a concomitant transient coronary occlusion (OC) or by treatment with aspirin.

METHODS

The myocardial content of 99mTc-labelled platelets was analyzed in 26 pigs submitted to intimal injury of the left anterior descending coronary artery (LAD) followed by no intervention (n=6), 25-min OC (n=6), or 48-min OC preceded (n=8) or not (n=6) by intravenous administration of 250 mg aspirin.

RESULTS

After 2 h, 24 animals had had 12+/-1 cyclic flow reductions (CFRs) reflecting dynamic LAD thrombosis. Myocardial platelet content in the inferior region was similar among groups. Platelet content in the LAD region was not significantly different to that in the inferior region (129+/-19%, P=NS) in the no intervention group, but was increased following OC (172+/-20 and 312+/-71% after 25- and 48-min OC, respectively, P<0.05). Pre-treatment with aspirin lessened the number of CFRs but did not reduce platelet accumulation in LAD myocardium (483+/-148%). Myocardial platelet accumulation was not associated with the magnitude of platelet deposition in the LAD nor with the number of CFRs, but was correlated with myeloperoxidase activity (r=0.91, P<0.001) and with infarct size (r=0.52, P=0.05). Histological analysis frequently showed sparse platelets or small platelet or leukoplatelet aggregates in small vessels, but arteriolar emboli were rare. In none of seven additional experiments coronary angiography showed obstructions of arterial branches during CFRs.

CONCLUSION

The magnitude of platelet embolization from a mural intracoronary thrombus into downstream myocardium is small despite the presence of repetitive CFRs.

Identification of stathmin as a novel substrate for p38 delta

p38 mitogen-activated protein kinases (MAPK) are a family of kinases that are activated by cellular stresses and inflammatory cytokines. Although there are many similarities shared by the isoforms of p38 (alpha, beta, gamma, and delta), p38 delta differs from the others in some respects such as inhibitor sensitivity and substrate specificity. Utilizing in a solution kinase assay, we identified a novel p38 delta substrate as stathmin. Stathmin is a cytoplasmic protein that was previously reported to be a substrate of several intracellular signaling kinases and has recently been linked to regulation of microtubule dynamics. p38 delta has significantly higher in vitro phosphorylating activity against stathmin than other p38 isoforms or related MAPKs. In transient expression studies, we found that in addition to different stimuli osmotic stress activates p38 delta to phosphorylate stathmin. The sites of phosphorylation were mapped to Ser-25 and Ser-38, both in vitro and in cells.

[Cost-effectiveness analysis of serum ferritin screening in periodic physical examinations of women at the fertile age]

BACKGROUND

Fertile-aged women are a population group at special risk for developing ferropenia. In the periodic health care examinations, hemogram, among other tests, are included to detect the most advanced state of iron deficity, ferropenic anemia. Likewise, preanemic ferropenia presents a certain morbidity. The aim of this study was to analyze the cost-effectiveness of screening serum ferritin determination in health care examinations of fertile-aged women.

SUBJECTS AND METHODS

An observational transversal study was carried out in 322 women in whom hemogram and serum ferritin were determined. The effects of serum ferritin determination were simulated in a hypothetical cohort of 20-year old women annually examined up to the age of 50 years (mean age of menopause).

RESULTS

The prevalence of preanemic ferropenia (serum ferritin < or = ng/ml) was 44.1% and that of ferropenic anemica (Hb < 120 g/l and serum ferritin < or = 25 ng/ml) was 3.4%. Hemogram sensitivity for detection of ferropenia was 7.2% (3.6-12.5). By means of the screening program with serum ferritin avoiding of one year with ferropenia costs 2,428 pesetas. Prolonging the program to longer than 35 years largely increases the marginal cost. Cost-effectiveness analysis is specially sensitive to the cost of the diagnostic tests and disease prevalence.

CONCLUSIONS

Ferropenia in fertile-aged women is a frequent disorder. Avoiding ferropenia by early diagnosis may be performed at a relatively low cost.

[The effect of 2 lipid emulsions on platelet function]

We examined the effect on platelet aggregation and activation and the production of eicosanoids in nonseptic critical patients of two lipidic emulsions administered with total parenteral nutrition. The two lipidic emulsions, Intralipid (20% of long chain triglycerides) and Lipofundina (10% each of long and medium-chain triglycerides), of differing essential fat acid content, provided 43% of the non-protein calorific requirements calculated for each patient. There were no other variables in the parenteral nutrition administered: the patients were distributed in two groups on a randomized basis according to the type of lipids received. We assessed the parameters demonstrating platelet function before parenteral nutrition, and after 4 and 7 days of such nutrition. Throughout the study, platelet aggregability was seen not to differ significantly from normal, even though the activation parameters controlled, beta TG and PF4, were from the outset significantly higher than normal; the thromboxane B2 averages calculated remained high, with wide individual variability, while averages for 6-keto-PGF1 alpha [correction of 0], which were initially high, showed a tendency (not statistically significant) to drop after 4 and 7 days nutrition. We did not observe that the administration of LCT or MTC/LCT led to changes in platelet aggregation and/or activation in the patients studied.

[Platelet hyperactivity in diabetic retinopathy: etiologic factor or epiphenomenon of microangiopathy?]

In order to analyze the etiologic and pathogenic meaning of platelet activity in diabetic retinopathy, Plasmatic Beta-Thromboglobulin (BTG) has been determined in 42 diabetics without retinopathy, 14 diabetics with non proliferative retinopathy and in 29 health controls. BTG showed higher values in diabetic patients with retinopathy in comparison with diabetics with no retinopathy (46.4 +/- 10.7 versus 37.6 +/- 13.4 ng/ml; p < 0.05 and with controls (31 +/- 18.8; p < 0.005). There were no differences between diabetics with no retinopathy and controls. No relation was found between BTG and the glycemic control grade, neither with lipoproteic profile. In resume, platelet hyperactivity found in patients with retinopathy seems to be an epiphenomenon of the microangiopathic lesion and not an etiologic factor, however this not precludes that it can play a role in the progression on retinal lesions.

[Platelet function study in primary Raynaud's phenomenon and Raynaud's phenomenon associated with scleroderma]

We evaluated platelet function in 59 patients with Raynaud's phenomenon (RP): 24 had primary RP (PRP) and in 35 RP was associated with diffuse scleroderma (DS). In the group with PRP there were 10 males and 14 females, with a mean age of 43 +/- 12 years and a time of evolution of 5 +/- 5 years. In the group with RP associated with DS there were 31 females and 4 males with a mean age of 53 +/- 12 years and a time of evolution of 9 +/- 7 years. The control group consisted of 20 healthy individuals (14 males and 6 females with a mean age of 40 +/- 12 years). In all patients and controls beta-thromboglobulin (BTG) and platelet factor 4 (PF4) levels were measured in plasma, and platelet aggregation was evaluated in the presence of adenosine diphosphate (ADP), collagen and arachidonic acid. The patients with RP associated with DS had BTG and PF4 higher than those with PRP and controls (p less than 0.02). The BTG/PF4 ratio was also significantly greater in patients with DS (p less than 0.005). The platelets from patients with DS had a greater aggregation with ADP (1 microM and 0.5 microM) than those from PRP (p less than 0.03). We concluded that patients with RP associated with DS had in vivo activation and a greater aggregation of platelets, in contrast with the absence of these findings in the group with PRP and in controls.

Intestinal permeability to 99mTc-diethylenetriaminopentaacetic acid in inflammatory bowel disease

Intestinal permeability in inflammatory bowel disease and its relation to periods of disease activity has been investigated by measuring the urinary excretion of DTPA labeled with 99mTc. Urine excretion in 10 control subjects was 2.7 +/- 1% of the test dose. Twelve patients with ulcerative colitis excreted 5.08 +/- 1.6% in remission, 10.61 +/- 2% during periods of mild activity, 19.41 +/- 0.9% during moderate activity, and 15.41 +/- 6.3% with severe activity. Sixteen patients with Crohn's disease excreted 5.7 +/- 1.9% in remission, 8.47 +/- 2.8% during mild activity of the disease, and 14.29 +/- 5.8% during moderate activity. No differences were observed between ulcerative colitis and Crohn's disease, or between ileal and colonic forms of Crohn's disease. Excretion in remission was significantly greater than in control subjects and there was a correlation between excretion and disease activity. In serial determinations done in seven patients we found that urine excretion of the test substance correlated with disease activity. We also studied DTPA excretion in 10 cases with gastric or duodenal ulcer (2.28 +/- 1.4%), six cases of acute gastroenteritis (4.87 +/- 3.1%) and nine cases with other intestinal diseases (3.6 +/- 1.1%). In all these cases, DTPA excretion was lower than in inflammatory bowel disease. Our results show that the urinary excretion of DTPA is a simple test that measures accurately the degree of activity of inflammatory bowel disease. The test is useful in Crohn's disease as well as in ulcerative colitis, and detects intestinal permeability abnormalities even in clinical remission. Significantly lower excretions are found in other intestinal diseases. The test may be recommended as a screening test for use in clinical practice.

[A study of anemia in 86 patients on hemodialysis (author's transl)]

Anemia is one of the complications of terminal chronic renal failure that may worsen with periodical hemodialysis because of residual blood losses in the dialyzers that may be significant if clotting occurs within the circulation system. The potential iron deficiency component of the anemia has been studied in 86 patients submitted to periodic hemodialysis by measurement of hemoglobin, serum iron, transferrin saturation, total iron binding capacity, and ferritin. The following correlations were investigated: degree of anemia and type of renal disease, months on hemodialysis and hemoglobin, months on hemodialysis and serum ferritin, and liters of blood transfused and serum ferritin. Statistically significant correlations were found between months on hemodialysis and hemoglobin, and between liters of blood transfused and serum ferritin. From the correlation between serum iron and ferritin the patients could be classified in three groups: 1, with either normal or low serum iron and ferritin, candidates to iron therapy; 2, with elevated serum iron and ferritin, needing no iron treatment; and 3, with unequal changes of serum iron and ferritin, in whom iron kinetic studies are indicated in order to discover the patents that may benefit from iron therapy.