The proteomics of roadside hawk (Rupornis magnirostris), broad-snouted caiman (Caiman latirostris) and loggerhead sea turtle (Caretta caretta) tears

Analysis and comparison of tear protein profiles in dogs using different tear collection methods

BACKGROUND

Tear proteomic analysis has become an important tool in medical and veterinary research. The tear collection method could influence the tear protein profile. This study aims to evaluate the protein profiles of dog tears collected using microcapillary tubes (MT), Schirmer tear strips (ST), and ophthalmic sponges (OS).

METHODS

The tear samples were collected using MT, ST, and OS. Tear protein profiles were analyzed using two-dimensional electrophoresis (2-DE) and the different protein spots' expression was compared. Fourteen protein spots were identified using liquid chromatography-tandem mass spectrometry (LC-MS/MS).

RESULTS

Tear protein concentrations ranged from 2.80 to 4.03 μg/μL, with no statistically significant differences among collection methods. Protein expression in each collection method differed in terms of both the number and intensity of the spots. There were 249, 327, and 330 protein spots found from tears collected with MT, ST, and OS, respectively. The proteins albumin, haptoglobin, and lactoferrin identified from OS were found to have higher spot intensities than other methods of collection. The use of MT demonstrated the downregulation of nine proteins.

CONCLUSIONS

The recent study supported that tear protein analysis is affected by different tear collection methods. Although ST is commonly used for tear collection, it provides insufficient information to study particular tear proteins.

Trace Elements in Tears: Comparison of Rural and Urban Populations Using Particle Induced X-ray Emission

We aimed to evaluate the types and concentrations of trace elements in tears of individuals living in urban and rural environments using particle induced X-ray emission (PIXE) and the possible association with exposure to air pollution and suggest a novel method for tear-based biomonitoring studies. This cross-sectional pilot study comprised 42 healthy subjects, 28 living in a rural area and 14 in an industrial city. Tears were collected with Schirmer paper and characterized by PIXE. Trace element concentrations from both eyes were averaged together with environmental pollution data. Main outcome measures were between-group differences in types and concentrations of trace elements in tears and comparison to environmental data. The rural group included 12/28 men, mean age 45.2 ± 14.8 years. The urban group consisted of 11/14 men of mean age 27 ± 5.9 years. Six rural and all urban were active smokers. Air pollution data showed more toxic elements in the rural environment. On PIXE analysis, chlorine, sodium, and potassium were found in similar concentrations in all samples. Normalizing to chlorine yielded higher values of aluminum, iron, copper, and titanium in the rural group; aluminum was found only in the rural group. The higher levels of certain trace elements in the rural group may, in part, be a consequence of exposure to specific environmental conditions. No direct association was found with air pollution data. PIXE is useful to analyze trace elements in tears, which might serve as a marker for individual exposure to environmental pollutants in biomonitoring studies.

Loggerhead sea turtle Caretta caretta plasma biochemistry and proteome profile modulation during recovery

The aim of the study was to monitor and analyse injured and diseased loggerhead sea turtles (Caretta caretta) plasma proteome profiles and biochemistry parameters during their recovery period in rescue centre within different age and recovery period groups, and determine the potential biomarkers that can be used in diagnostics. The plasma biochemical parameters of total protein and glucose content, accompanied by aspartate aminotransferase (AST) and N-acetyl-cystein-activated creatinine kinase (CK-NAC) are highlighted as valuable and potential biomarkers of turtle's health status and condition. Using high throughput tandem mass tag (TMT)-based proteomic approach we identified 913 plasma proteins, 12 of which shown to be modulated in loggerheads age groups, and identified as a part of (i) platelet degranulation, (ii) neutrophil degranulation, and (iii) innate immune system pathways. The neurofascin (NFASC) is shown to be differentially abundant among all the age groups, and alpha-1-acid glycoprotein 2-like (ORM2) and alpha-1-antitrypsin-like (SERPINA1) proteins were recognized as members of all three above mentioned REACTOME pathways. Furthermore, 29 of plasma proteins were significantly differentially abundant in loggerheads age and recovery period groups. Out of 15 recognized pathways, those proteins were mostly included in three specific REACTOME pathways: (i) post-translational phosphorylation, (ii) regulation of Insulin-like Growth Factor (IGF) transport and uptake by Insulin-like Growth Factor Binding Proteins (IGFBPs), and (iii) platelet degranulation. The alpha-fetoprotein (AFP) was the only protein which showed statistically significant up-regulation patterns in all loggerhead age groups before release from the rescue centre, and the complement component 3 (C3) protein was the only protein modulated in all recovery period groups. Furthermore, C3 protein takes part in 9; and followed up with apolipoprotein A-I (APOA1) in 7; complement component 4 (C4), complement component 5 (C5) and kininogen-1 (KNG1) in 6 REACTOME pathways. Thereby, those proteins are highlighted and recommended as potential biomarkers of turtle's health status. Data are available via ProteomeXchange with identifier PXD029569. Finally, based on our results, we believe that comprehensive omics approach and routine plasma biochemical analysis, accompanied by proteins of acute phase, acid-base status and immune-response indicator analysis may significantly and reliably improve assessment of captive loggerheads rehabilitation and medication. SIGNIFICANCE: Monitoring and comparison of loggerhead sea turtles (C. caretta) blood plasma biochemistry parameters and plasma proteome profiles in relation to the age, and recovery period pointed out significantly differentially abundant proteins, along with certain biochemical parameter contents as potential biomarkers of turtle's fitness, health status and physiology.

The glycoproteomics of hawk and caiman tears

BACKGROUND

Glycoproteins are important tear components that participate in the stability of the ocular surface. However, the glycopeptides that are present in the tears of wild animals have not yet been described. This work aimed to describe the glycoproteomic profile of roadside hawk (Rupornis magnirostris) and caiman (Caiman latirostris) tears.

METHODS

Tears collected from 10 hawks and 70 caimans using Schirmer tear test strips were used in this study. The samples were submitted to trypsin digestion and separated using a reverse-phase column coupled to a mass spectrometer associated to a nanospray ionization source. The glycoproteins were categorized as: cellular components, biological processes and molecular function, according to the UniProt Knowledgebase.

RESULTS

As shown by the liquid chromatography-mass spectrometry, all glycopeptides found were classified as N-type. Of the 51 glycoproteins that were identified in the hawk tear film, the most abundant were ovotransferrin, globulins and complement system proteins. In the caiman tear film, 29 glycoproteins were identified. The most abundant caiman glycoproteins were uncharacterized proteins, ATPases, globulins and proteasome components. Ontological characterization revealed that the glycoproteins were extracellular, and the most identified molecular function was endopeptidase activity for both species.

CONCLUSION

Glycoproteins are abundant in the tear film of the bird and reptile species studied herein, and all these molecules were shown to have N-type modifications. Location at the extracellular space and an endopeptidase inhibitor activity were the main cell component and molecular function for both species, respectively. These profiles showed differences when compared to human tears, are possibly linked to adaptive processes and can be the basis for further studies on the search of disease biomarkers.

The Albumin-to-Fibrinogen Ratio Independently Predicts Acute Kidney Injury in Infants With Ventricular Septal Defect Undergoing Cardiac Surgery With Cardiopulmonary Bypass

Background: Acute kidney injury (AKI) is a common and serious complication faced by children following ventricular septal defect (VSD) surgery with cardiopulmonary bypass (CPB). The objective of this study was to explore potential predictors inherent to AKI. Methods: VSD infants who were scheduled for elective cardiac surgery with CPB from 2017 to 2020 were enrolled in this study. Based on the Pediatric Risk, Injury, Failure, Loss, End-Stage Renal Disease (pRIFLE) criteria, patients were divided into AKI and non-AKI groups. Univariate and multivariate logistic regression analyses were carried out in order to evaluate potential risk factors for AKI. Receiver operating characteristic (ROC) curves were generated to evaluate the predictive probabilities of risk factors for AKI. Results: Of all the 338 enrolled VSD infants, 49 manifested AKI with an incidence of 14.5% (49/338). The ROC curve indicated that albumin-to-fibrinogen ratio (AFR) during CPB was a significant predictor of AKI [area under the curve (AUC), 0.711; p < 0.001]. Based on the univariate and multivariate logistic analyses, AFR during CPB [odds ratio (OR), 1.89; 95% confidence interval (CI), 1.22-2.76, p = 0.011] was the only independent risk factor for AKI. Conclusions: This study demonstrated that a low AFR (<9.35) during CPB was an independent risk factor for AKI in VSD infants following cardiac surgery with CPB.