Biomarkers in fish as a measure of the state of marine environment of Kuwait

The health of a marine ecosystem can effectively be monitored by studying the levels of biomarkers in a representative species. A change in background level of a biomarker indicates exposure to a specific type of pollutants. It also identifies bioavailability and the organism response to the causative agent among the compounds present in the surrounding water body. Yellowfin seabream (Acanthopagrus latus), a local variety of fish, was examined for parent PAHs in the liver, its metabolites in bile by the GC-MS method as exposure biomarkers and cytochrome P4501A1 by assay of ethoxyresorufin-o-deethylase (EROD) in the liver as an effect biomarker. A comparison was made between fish collected in 2015 with the fish collected in 2005-2006 and stored at - 80 °C in the fish bank. The objective was to examine the extent of changes in the environmental quality of the Kuwait marine area and the status of fish health concerning oil-related pollutants since Arabian Gulf is surrounded by oil-producing countries. Interestingly, insignificant differences between the liver PAH content and EROD activity were observed in fish over the sampling periods. The fish efficiently metabolized PAHs and excreted hydroxy-metabolites in bile. The study suggested that environmental quality of the Kuwait marine area was not deteriorated to any serious extent in the last decade and biomarkers can be used effectively in assessing the thrust of sub-optimal levels of various contaminants present in the marine area on the resident biota.

Imaging Regional Metabolic Changes in the Ischemic Rat Heart In Vivo Using Hyperpolarized [1-13C]Pyruvate

We evaluated the use of hyperpolarized ¹³C magnetic resonance imaging (MRI) in an open-chest rat model of myocardial infarction to image regional changes in myocardial metabolism. In total, 10 rats were examined before and after 30 minutes of occlusion of the left anterior descending coronary artery using hyperpolarized [1-¹³C]pyruvate. Cardiac metabolic images of [1-¹³C]pyruvate and its metabolites [1-¹³C]lactate, [1-¹³C]alanine, and [¹³C]bicarbonate were obtained before and after ischemia. Significant reduction in the [1-¹³C]alanine and [1-¹³C]lactate signals were observed in the ischemic region post ischemia. The severity of the ischemic insult was verified by increased blood levels of troponin I and by using late contrast-enhanced MRI that showed enhanced signal in the ischemic region. This study shows that hyperpolarized MRI can be used to image regional metabolic changes in the in vivo rat heart in an open-chest model of ischemia reperfusion. Hyperpolarized MRI enables new possibilities for evaluating changes in cardiac metabolism noninvasively and in real time, which potentially could be used for research to evaluate new treatments and metabolic interventions for myocardial ischemia and to apply knowledge to future application of the technique in humans.

Seasonal effect on biomarkers of exposure to petroleum hydrocarbons in fish from Kuwait's marine area

The aquatic biota of the Arabian Gulf deals with exposure to chronic oil pollution, several constituents of which cause induction of Cytochrome P450 1A that serves as a biomarker of AhR ligand exposure. In this study, fluorescent aromatic compounds (FACs) in bile and 7-ethoxyresorufin-o-deethylase (EROD) catalytic activity were determined as a measure of exposure biomarkers in two fish species, yellow fin seabream (Acanthopagrus latus) and tonguesole (Cynoglossus arel) captured from Kuwait Bay and outside the Bay area. FACs in fish bile determined by using fixed-wavelength fluorescence (FF) showed high fluorescence ratios between FF290/335 and FF380/430 indicating predominant exposure to low molecular weight, naphthalene-rich petroleum products (375±91.0 pg ml(-1)). Exposures to benzo(a)pyrene-type high-molecular weight polycyclic aromatic hydrocarbons (PAHs) originating from burnt fuel were also present in appreciable concentration in the bile. The ratio of petrogenic to pyrogenic hydrocarbon was twofold higher in winter compared to summer months in both species. Seasonal effect on EROD was significant in tonguesole in Auha site (P<0.05); whereas seabream resisted seasonal change. Tonguesole is considered to be a suitable bioindicator of oil pollution in Kuwait Bay area.

Metallothionein, oxidative stress and trace metals in gills and liver of demersal and pelagic fish species from Kuwaits' marine area

Two fish species yellowfin seabream (Acanthopagrus latus) and tonguesole (Cynoglossus arel) were collected from two locations in Kuwait's territorial waters in non-reproductive periods and used as bio-indicator organism for the assessment of metals in the marine environment. Species variation in fish was observed; seabream contained high metal content and metallothionein in liver and gill tissues compared to tonguesole, especially from Kuwait Bay area. Oxidative injury was registered in the gills of both species, but in tonguesole liver was also involved. Consequently, antioxidant enzyme catalase was elevated in tonguesole enabling bottom dwelling fish to combat oxidative assault. The study provided information about the current status of metals in marine sediment and levels of metals accumulated in representative species along with oxidative damage in exposed tissues and the range of biomarker protein metallothionein and enzymes of antioxidant defence mechanism enhancing our understanding about the biological response to the existing marine environment in Kuwait.

Comparison of three commercial RT-PCR systems for the detection of respiratory viruses

BACKGROUND

Due to the insensitivity of rapid tests for respiratory viruses, nucleic acid amplification tests are quickly becoming the standard of care.

OBJECTIVES AND STUDY DESIGN

The performance of the FilmArray Respiratory Panel (RP) and Verigene RV+ (RV+) were compared in a retrospective analysis of 89 clinical specimens previously determined to be positive for the following viruses by our test of record, Prodesse (Pro): influenza A (29, FluA), influenza B (13, FluB), respiratory syncytial virus (12, RSV), human metapneumovirus (10, hMPV), parainfluenza (14, PIV), and adenovirus (10, AdV). Samples positive for influenza A, B or RSV were tested by both methods, while the remainder were tested by RP only. True positives were defined as positive by two or more assays.

RESULTS

Limit of detection (LOD) analyses demonstrated Pro had the lowest LOD for all FluA strains tested, PIV1, PIV2 and AdV; RV+ had the lowest LOD for FluB; and RP had the lowest LOD for RSV, PIV3 and hMPV. Of the 55 samples tested by RV+, all 54 true positive samples were positive by RV+. Of the 89 samples tested by RP, 85 of the 88 true positive samples were positive by RP. From these results, the overall sensitivities for influenza A, B and RSV were 100% and 98% for RV+ and RP, respectively. The overall sensitivity of RP for all viruses was 97%.

CONCLUSIONS

In summary, these systems demonstrated excellent performance. Furthermore, each system has benefits which will ensure they will all have a niche in a clinical laboratory.

Monitoring mammary tumor progression and effect of tamoxifen treatment in MMTV-PymT using MRI and magnetic resonance spectroscopy with hyperpolarized [1-13C]pyruvate

PURPOSE

To use dynamic magnetic resonance spectroscopy (MRS) of hyperpolarized (13)C-pyruvate to follow the progress over time in vivo of breast cancer metabolism in the MMTV-PymT model, and to follow the response to the anti-estrogen drug tamoxifen.

METHODS

Tumor growth was monitored by anatomical MRI by measuring tumor volumes. Dynamic MRS of hyperpolarized (13)C was used to measure an "apparent" pyruvate-to-lactate rate constant (kp) of lactate dehydrogenase (LDH) in vivo. Further, ex vivo pathology and in vitro LDH initial reaction velocity were evaluated.

RESULTS

Tamoxifen significantly halted the tumor growth measured as tumor volume by MRI. In the untreated animals, kp correlated with tumor growth. The kP was somewhat but not significantly lower in the treated group. Studies in vitro confirmed the effects of tamoxifen on tumor growth, and here the LDH reaction velocity was reduced significantly in the treated group.

CONCLUSION

These hyperpolarized (13)C MRS findings indicate that tumor metabolic changes affects kP. The measured kp did not relate to treatment response to the same extent as did tumor growth, histological evaluation, and in vitro determination of LDH activity.

Enhancing the [13C]bicarbonate signal in cardiac hyperpolarized [1-13C]pyruvate MRS studies by infusion of glucose, insulin and potassium

A change in myocardial metabolism is a known effect of several diseases. MRS with hyperpolarized (13)C-labelled pyruvate is a technique capable of detecting changes in myocardial pyruvate metabolism, and has proven to be useful for the evaluation of myocardial ischaemia in vivo. However, during fasting, the myocardial glucose oxidation is low and the fatty acid oxidation (β-oxidation) is high, which complicates the interpretation of pyruvate metabolism with the technique. The aim of this study was to investigate whether the infusion of glucose, insulin and potassium (GIK) could increase the myocardial glucose oxidation in the citric acid cycle, reflected as an increase in the [(13)C]bicarbonate signal in cardiac hyperpolarized [1-(13)C]pyruvate MRS measurements in fasted rats. Two groups of rats were infused with two different doses of GIK and investigated by MRS after injection of hyperpolarized [1-(13)C]pyruvate. No [(13)C]bicarbonate signal could be detected in the fasted state. However, a significant increase in the [(13)C]bicarbonate signal was observed by the infusion of a high dose of GIK. This study demonstrates that a high [(13)C]bicarbonate signal can be achieved by GIK infusion in fasted rats. The increased [(13)C]bicarbonate signal indicates an increased flux of pyruvate through the pyruvate dehydrogenase enzyme complex and an increase in myocardial glucose oxidation through the citric acid cycle.

Seasonal effect on heat shock proteins in fish from Kuwait bay

Heat shock proteins (HSP70) play a significant role in adaptation to temperature and have been proposed as an indicator of cellular stress. Since the water temperature in Kuwait's marine area varies from 13 to 35 degrees C from winter to summer, HSP70 could be a valuable tool in aquaculture in Kuwait. HSP70 levels were quantified by Western blotting in liver, muscle and gill tissues of two varieties of native fish species captured during the winter and summer months from both inside and outside the highly stressed Kuwait Bay area. The HSP70 levels did not differ statistically between fish captured from the two sampling areas. The most common response in both species was higher median levels of HSP70 in winter months. This inverse relation between HSP70 levels in the fish and the water temperature may be due to either genetic adaptation in the fish to the hot climatic conditions of the region or other stressors, such as changes in pollutant levels in the surrounding water.

Reliability of commercially available immunocytochemical markers for identification of neuroendocrine differentiation in bronchoscopic biopsies of bronchial carcinoma

BACKGROUND

Although neuroendocrine differentiation occurs quite commonly in non-small cell bronchial malignancies, its biological significance and implications for management remain uncertain. Determining these facts requires its recognition early, ideally at diagnosis, which is usually made on tissue from bronchoscopy, but the best means of its detection in such material is unclear. A prospective comparative study was performed of 10 commercially available antisera to a series of markers of neuroendocrine differentiation, to test their efficacy when applied to fibreoptic bronchoscopy biopsy specimens.

METHODS

Expression of chromogranin A, synaptophysin, neurone-specific enolase, protein gene product 9.5, the BB isoenzyme of creatine kinase, gastrin releasing peptide, adrenocorticotrophic hormone, calcitonin, calcitonin gene related peptide, and leucine enkephalin was sought by immunolabelling of bronchoscopic biopsy tissue from 83 primary bronchial carcinomas, 22 of them of small cell type.

RESULTS

Only synaptophysin and chromogranin were sensitive and specific enough for neuroendocrine differentiation to discriminate between small cell and non-small cell lesions, whereas protein gene product 9.5 and creatine kinase were neither particularly sensitive nor specific and neurone-specific enolase actually labelled more non-small cell tumours than small cell lesions. Of the five secretory products sought, only gastrin releasing peptide was detectable in just one tumour. Three squamous and two morphologically undifferentiated tumours immunolabelled for synaptophysin and chromogranin, almost certainly indicating neuroendocrine differentiation in the absence of small cell morphology.

CONCLUSIONS

Of the markers studied, only synaptophysin and chromogranin were sufficiently specific and sensitive for neuroendocrine differentiation to justify their inclusion in any panel of antibodies used in its detection in tissue obtained at fibreoptic brochoscopy.

Exposure to cigarette smoke and expression of the protein encoded by the p53 gene in bronchial carcinoma

Mutation of the onco-suppressor gene encoding the protein known as p53 may cause synthesis of a mutant p53 protein which can bind to and inactivate its wild-type equivalent. This protein is detectable in many malignant neoplasms, including bronchial carcinoma, and has been associated with cigarette smoking. Of 59 tissue biopsy specimens of primary bronchial malignancies immunolabeled for p53 by the avidin-biotin technique using the antibodies PAb 1801, CM1, and D07, 13 (22%) expressed the protein. Of these 13 patients, 10 (77%) smoked more than 20 cigarettes a day and their mean total exposure was 53 pack-years. Corresponding figures for those with p53-negative tumors were 21 (46%) smoking more than 20 cigarettes a day with a mean total exposure of 36 pack-years. There was, however, no difference between the groups in total duration of exposure (46 vs. 47 years). Although p53 was expressed more commonly in adenocarcinoma (30% of 10) and squamous carcinoma (28% of 29) than in small cell tumors (10% of 20), this could be accounted for by the smoking history. This study supports a relationship between mutations of the p53-encoding gene associated with overexpression of its protein product and intensity of exposure to cigarette smoke.

c-myc oncoprotein in bronchial carcinoma: expression in all major morphological types

We have studied the prevalence of a 62 kd protein product of the c-myc oncogene in tissue biopsies from 79 primary bronchial carcinomata using the monoclonal antibody Myc 1-9E10 and the avidin-biotin complex (ABC) technique. This oncoprotein was strongly expressed in 43% of 37 squamous lesions, 29% of 14 adenocarcinomata, 42% of 7 non-small cell lesions not further classifiable and 19% of 21 small cell neoplasms, all of classical morphology. There was no statistical difference between groups in the prevalence of its expression, nor was it related to survival. This oncoprotein is commonly expressed in non-small cell as well as small cell bronchial carcinomata and, in the latter, is not confined to those variant tumours which possess a "large cell" morphology and carry a poor prognosis.