Molecular characterization of Lernathropus kroyeri from intensive aquaculture and pathophysiology of infested sea bass

The copepod Lernathropus kroyeri constitutes one of the major parasites for the Mediterranean aquaculture, infesting the sea bass Dicentrarchus labrax causing thus disruptions of growth performance and occasionally mortalities. Despite the large spread and the high frequency of this parasite in mariculture farms of Eastern Mediterranean, L. kroyeri genetic profile from aquaculture as well as the pathophysiological response of D. labrax have not been studied so far. Keeping this in mind, in the present study we investigated the L. kroyeri infestation on D. labrax from two farms in Greece, examining both healthy and heavy parasitized individuals. Assays included histopathology, phylogenetic reconstruction of the parasite and physiological response of the fish by the means of antioxidant, inflammatory metabolic and stress related gene expression analysis at both mRNA and protein levels. Genetic analysis indicated that L. kroyeri composes a monophyletic group, highly phylogenetically distant from other congeneric groups. Heavy infested D. labrax witnessed a significantly increased immune response that further led to oxidative stress and metabolic alterations. Overall, our results demonstrate the, seasonally independent, high infestation of this parasitic copepods, which continue to affect Mediterranean intensive aquaculture systems.

Spontaneous coronary artery dissection – contemporary management and outcome of a national cohort

Background

Spontaneous coronary artery dissection (SCAD) is proposed to cause 1–4% of all acute myocardial infarctions (AMI).

The aim of this study was to conduct a first description of Swedish SCAD patients regarding the prevalence of risk factors, treatment and prognosis.

Method

All patients with AMI registered in the Swedish Coronary Angiography and Angioplasty Register (SCAAR) December 2015 until December 2017 were included. The index angiographies of the SCAD patients were reevaluated by an independent angiographer at each center. Patients with non-SCAD AMI (n=31670) were used for comparison.

Results

SCAD was identified in 137 patients with AMI (100 women, 37 men). The SCAD population was younger than the non-SCAD population 53.9 (51.7–56.1) vs 68.5 (68.3–68.6) years, more often women (73.0 vs 30.7%) and presented with less risk factors: diabetes 2.9 vs 20.8%; hypertension 27.0 vs 57.6%; smoking 41.2 vs 58.1%; statin therapy 12.4 vs 36.9% and previous AMI 7.3 vs 19.6% (p<0.001 for all comparisons).

SCAD patients less frequently underwent percutaneous coronary intervention (PCI) 43.1 vs 70.8% (p<0.001) and received less statin treatment, 78.9 vs 91.5% (p<0.001).

There was no significant difference regarding treatment with aspirin or double antiplatelet therapy at discharge: 93 vs 89.7% (p=0.45) and 86.7 vs 84.2%, respectively (p=0,43).

There was no significant difference in one-year mortality 6.6 vs 8.2% (p=0.57).

Conclusions

With a current prevalence of 0.43% of all Swedish AMIs, data supports SCAD being an underdiagnosed condition with a prognosis resembling that of non-SCAD AMI. Furthermore, SCAD patients are younger and harbor less cardiovascular risk factors. While significant differences in management are present, current therapeutic strategies of the two groups are similar, indicating overtreatment of SCAD.

Funding Acknowledgement

Type of funding source: Foundation. Main funding source(s): Swedish Heart-Lung foundation, ALF funding

Immune responses to the 105AD7 human anti-idiotypic vaccine after intensive chemotherapy, for osteosarcoma

105AD7 is a human monoclonal antibody that mimics the complement regulatory protein, CD55, overexpressed by many solid tumours including osteosarcoma. This study was designed to assess the toxicity and efficacy of this vaccine in a young age group of patients within 1–6 months of myleosuppressive chemotherapy. Out of 28, 20 (71%, 95% CI 51–87%) patients showed a significant T-cell proliferation response in vitro to the 105AD7 protein but not to human IgG. Furthermore, 13 out of 22 (59%, 95% CI 36–79%) patients showed antigen-specific γIFN secretion (range 20–370 U/ml). Nine out of 28 (32%, 95% CI 16–52%) patients made weak antibody responses to CD55. This study showed that 105AD7 was well tolerated in younger patients with osteosarcoma. In addition, two patients with possible clinical responses were given compassionate permission to continue immunisation quarterly for 2 years. They both remain alive and disease free 5.8 and 6.5 years from original diagnosis of osteosarcoma and showed no adverse effects of repeated immunisation. In conclusion, the majority of patients showed measurable T helper responses when vaccination was commenced within a 6-month window of intensive chemotherapy with no clinically significant toxicity. Future clinical trials incorporating immune stimulation strategies should include early introduction of vaccines during the highest risk period for relapse.

A phase I trial of amsalog (CI-921) administered by intravenous infusion using a 5-day schedule

PURPOSE

Amsalog, a derivative of 9-aminoacridine, is an inhibitor of topoisomerase II. Early studies of intravenous amsalog administered either once weekly, or daily for 3 days repeated every 3 weeks, showed that myelosuppression is the dose-limiting toxicity (DLT). Phase II studies showed only limited activity in breast, head and neck, and non-small-cell lung cancer. The activity of other topoisomerase inhibitors is schedule-dependent. We therefore performed a phase I study to evaluate the use of amsalog on a more prolonged schedule.

METHODS

A group of 19 patients with refractory malignancies were treated in six cohorts using 2-h infusions of amsalog daily for 5 days, repeated every 3 weeks.

RESULTS

Myelosuppression was seen as DLT at 200 mg/m2 per day. Other toxicities included nausea and vomiting, fatigue, and, when administered via a peripheral venous line, severe phlebitis necessitating administration via an indwelling central venous catheter for doses greater than 100 mg/m2. Pharmacokinetic studies showed a linear relationship between Cmax and AUC, and dose. The terminal half-life was 2 h, consistent with previous studies.

CONCLUSION

We conclude that amsalog can be safely given on a 5-day schedule every 3 weeks at doses up to 200 mg/m2. The dose recommended for further studies is 180 mg/m2 per day for 5 days repeated every 3 weeks. However, in view of the phlebitis, which necessitated the use of central venous catheters for administration, other routes of administration, for example oral formulations, should be explored.

Phase I and pharmacokinetic study of D-limonene in patients with advanced cancer. Cancer Research Campaign Phase I/II Clinical Trials Committee

PURPOSE

D-Limonene is a natural monoterpene with pronounced chemotherapeutic activity and minimal toxicity in preclinical studies. A phase I clinical trial to assess toxicity, the maximum tolerated dose (MTD) and pharmacokinetics in patients with advanced cancer was followed by a limited phase II evaluation in breast cancer.

METHODS

A group of 32 patients with refractory solid tumors completed 99 courses of D-limonene 0.5 to 12 g/m2 per day administered orally in 21-day cycles. Pharmacokinetics were analyzed by liquid chromatography-mass spectrometry. Ten additional breast cancer patients received 15 cycles of D-limonene at 8 g/m2 per day. Intratumoral monoterpene levels were measured in two patients.

RESULTS

The MTD was 8 g/m2 per day; nausea, vomiting and diarrhea were dose limiting. One partial response in a breast cancer patient on 8 g/m2 per day was maintained for 11 months; three patients with colorectal carcinoma had prolonged stable disease. There were no responses in the phase II study. Peak plasma concentration (Cmax) for D-limonene ranged from 10.8+/-6.7 to 20.5+/-11.2 microM. Predominant circulating metabolites were perillic acid (Cmax 20.7+/-13.2 to 71+/-29.3 microM), dihydroperillic acid (Cmax 16.6+/-7.9 to 28.1+/-3.1 microM), limonene-1,2-diol (Cmax 10.1+/-8 to 20.7+/-8.6 microM), uroterpenol (Cmax 14.3+/-1.5 to 45.1+/-1.8 microM), and an isomer of perillic acid. Both isomers of perillic acid, and cis and trans isomers of dihydroperillic acid were in urine hydrolysates. Intratumoral levels of D-limonene and uroterpenol exceeded the corresponding plasma levels. Other metabolites were trace constituents in tissue.

CONCLUSIONS

D-Limonene is well tolerated in cancer patients at doses which may have clinical activity. The favorable toxicity profile supports further clinical evaluation.

Increased dihydropyridine-sensitive calcium channels in rat brain may underlie ethanol physical dependence

Ethanol physical dependence can be viewed as a state of latent hyperexcitability in brain which is exposed on withdrawal of the drug. This hyperexcitability may reflect an increased sensitivity to Ca2+ of central neurones. Dihydropyridine (DHP) binding sites which represent a subtype of neuronal Ca2+-channel, are increased in brains from ethanol-dependent rats as are functional effects of the DHP Ca2+-channel activator, BAYK8644. These effects are reversed by DHP Ca2+ inhibitors, which also prevent the ethanol physical withdrawal syndrome. These results suggest that an increase in DHP-sensitive Ca2+-channels on central neurons may represent the molecular basis for ethanol physical dependence.

Flavonoid impairment of neutrophil response

Flavonoids are a class of phenolic plant pigments which impair the oxidative burst of neutrophils to an extent dependent on their hydrophobicity. The distribution of quercetin and of morin in nitrogen-cavitated neutrophils paralleled their respective hydrophobic characteristics and respiratory burst inhibition. While both flavonoids were localized primarily in the specific granule membrane of neutrophils, the amount of quercetin was considerably greater than that of morin. We here demonstrate inhibition of the initial stimulation response, depolarization of the membrane potential as monitored by fluorescence of the membrane probe diS-C3-(5), and of the respiratory burst, monitored by following the destruction of diS-C3-(5), a reaction mediated by the H2O2 produced in the burst. The flavonoids kaempferol, morin, quercetin, or fisetin were preincubated with human neutrophils at a concentration of 100 microM per 2 X 10(6) cells/ml for 2-3 min and subsequently stimulated with 1 microgram/ml of the tumor promoter phorbol myristate acetate (PMA) or with 60 micrograms/ml of immune complex. The effect of each compound differed, i.e. depolarization was enhanced by some and inhibited by others, while H2O2 generation was inhibited by each, supporting our previous findings that membrane potential depolarization and the respiratory burst are dissociable events. Concentration-response experiments, performed at flavonoid concentrations between 12.5 and 500 microM to determine the IC50 values of these compounds for depolarization and burst activation, indicated that none of the flavonoids affected the resting potential, while all perturbed the stimulus-coupled response, the direction and extent of the perturbation depending upon the stimulus, and the function assessed. These data show that the effects of flavonoids on human neutrophils are complex and suggest several sites of action depending upon the flavonoid's subcellular distribution and pathway of stimulation.

Alterations in Ca2+-dependent and Ca2+-independent release of catecholamines in preparations of rat brain produced by ethanol treatment in vivo

Compared to preparations from control animals, superfused striatal slice preparations from brains of rats treated chronically with ethanol released a significantly greater fraction of stored [3H] dopamine on depolarisation in 40 mM K+. Similarly, the electrically-evoked release of [3H]-norepinephrine from cortical slices and of [3H]-dopamine from striatal slices is also increased, although with this mechanism of depolarisation the change is significant only in the case of [3H] norepinephrine release. In contrast to this tendency to enhancement of Ca2+-dependent depolarisation-induced release, a reduced fraction of stored [3H]-catecholamines was released from these preparations by the indirect sympathomimetics tyramine and (+)-amphetamine. The catecholamine release induced by these indirect sympathomimetics is largely independent of external Ca2+ and the results are interpreted as suggesting that chronic alcohol treatment changes the distribution of catecholamine neurotransmitters between storage pools in the nerve terminal which do or do not require Ca2+ entry for release.