The analysis of fatty acids and their derivatives in the liver of C57BL/6 mice with long-term caloric restrictions

Caloric restriction (CR) is a dietetic intervention based on the reduction of daily calorie intake by 10-30 %. When subjected to CR, the organism adjusts its metabolism to the changing availability of key nutrients. However, fatty acids' content in organisms subjected to long-term CR has not been evaluated. The aim of the research was to analyze the influence of long-term CR on the contents of medium- and long-chain fatty acids, as well as on the contents of fatty acid derivatives in liver. The study was performed on C57BL female (n = 12) and male (n = 12) mice subjected to lifelong 30 % calorie restriction. Fatty acids were analyzed using gas chromatography, while fatty acid derivatives were analyzed with liquid chromatography. The dynamics of change of the lipid profile of the labeled fatty acids observed in the liver tissue confirms that lipolysis actively takes place in this organ when hungry. Moreover, it is highly possible that de novo synthesis of acids takes place, with the aim to ensure energy substrates to the body. Moreover, an increase of concentration was observed for fatty acid derivatives, those with anti-inflammatory properties (resolvin, LTX A4). However, there was no increase in the concentration of pro-inflammatory eicosanoids. The results suggest that it is important to take into consideration the introduction of appropriate supplements when using CR.

Microbiota-derived metabolites in colorectal cancer patients in preoperative period

OBJECTIVE

Short-chain fatty acids (SCFAs) are microbial derived metabolites, which have multiple beneficial properties. The amount of SCFAs depends on several factors, such as age, diet (mainly intake of dietary fiber), and overall health condition. The normal proportion between SCFAs is 3:1:1 for acetate, proprionate and butyrate, respectively. In colorectal cancer (CRC) patients, microbiota alterations have been shown. Consequently, metabolome within the gut might change to a large extent. Therefore, the aim of this study was to analyse the content of SCFAs and the proportion between SCFAs in the stool obtained from CRC patients in preoperative period.

PATIENTS AND METHODS

This study included 15 patients with CRC in preoperative period. The stool samples were taken and stored at -80°C in the Fahrenheit Biobank BBMRI.pl, Medical University of Gdansk, Poland. The analysis of SCFAs from stool samples was conducted by means of gas chromatography.

RESULTS

This study included mainly males (66.67%, n=10). In all patients, there was abnormal proportion between SCFAs. The extremely higher concentration of butyrate was noted in 2 samples (13.33%) compared to the rest of patients. However, based on normal proportion between SCFAs, the results <1 for butyrate were noted in 93.33% of patients.

CONCLUSIONS

SCFAs pool is altered in CRC patients, among others characterized by low level of butyrate. It should be considered to administer butyrate supplementation to CRC patients especially prior to surgery to support an appropriate preparation to this treatment.

The therapeutic potential of relaxin for heart failure with preserved ejection fraction

Background and significance

Heart Failure (HF) is the leading cause of cardiovascular deaths and ∼50% of HF patients have HF with preserved ejection Fraction (HFpEF). HFpEF patients typically have co-morbidities such as atrial fibrillation (AF), diabetes, lung edema and hypertension. The latter is a predictor of mortality and is targeted to prolong survival given the lack of a direct therapy for HFpEF. To address this unmet public health problem, we investigate the therapeutic potential of the insulin-like hormone Relaxin (RLX) in a rat model of HFpEF that recapitulates most aspects of clinical HFpEF.

Methods

ZSF1 diabetic rats were placed on a high fat diet (HFD for 11-weeks) and echocardiograms were used to track HFpEF development. At week 20, osmotic mini-pumps were implanted to release vehicle (Na-acetate) or RLX (400μg/kg/day, 2-weeks). Hearts were then perfused with a voltage-sensitive dye (RH237) and a Ca2+ indicator (Rhod-2/AM) to optically map action potentials and Ca2+ transients and analyze arrhythmia phenotype. Left ventricular (LV) tissue sections were used for immune-fluorescence (IF) imaging for changes in fibrosis (collagen 1), connexin 43, Wnt1 and β-catenin in LV myocytes. Blood draws were taken to measure changes in serum NT-pro-ANP, ET-1 and RLX.

Results

ZSF1 rats on a HFD developed HFpEF with E/e' (an echo marker of diastolic dysfunction) decreasing to −24.4 from −17.9 MV (n=12) and was reversed to −18.6 MV by RLX (n=6, p&lt;0.0001). In HFpEF rats that received the vehicle (n=6), a premature stimulus (S1-S2= 40 ms) elicited: a) no arrhythmia b) non-sustained AF or c) sustained AF, with (1/3 of rats in each group). RLX blocked sustained supraventricular (n=0/12) and n=4/12 had non-sustained AF. RLX improved conduction velocity (CV), at short cycle lengths (150 ms) from 0.74 to 0.9 m/s (n=4/group). IF indicated that RLX increased Cx43 (26.8±0.03%, p&lt;0.0001, n=6), and β-catenin (52.8±0.05%, p&lt;0.0001) at intercalated disks. RLX reduced collagen deposition in HFpEF rats (25±0.04%, p&lt;0.04, back to normal) and caused a marked increase of cytosolic Wnt1 (47.3±0.06%, p&lt;0.0001). IF data are given as mean ± SEM.

Conclusions

The ZSF1 diabetic rat on a high-fat diet recapitulates most of the phenotypes associated with human HFpEF, including atrial arrhythmias, fibrosis, and lung edema. RLX treatment post-development of HFpEF reversed the pro-arrhythmic phenotype, increased conduction velocity particularly at fast heart rates, reversed fibrosis, reduced NT-pro-ANP and ET-1 in male rats. Most intriguing, RLX treatment activated Wnt1 and β-catenin indicating that the beneficial actions of RLX occur via genomic remodeling of the heart.

Funding Acknowledgement

Type of funding sources: Private company. Main funding source(s): Relaxera Pharmazeutische Gesellschaft mbH & Co. KGStubenwald-Allee 8a, 64625 Bensheim, Germany & Uhlandstraße 4-5, 10623 Berlin, Germany

Synergistic therapeutic benefit by combining the antibody drug conjugate, depatux-m with temozolomide in pre-clinical models of glioblastoma with overexpression of EGFR

PURPOSE

Depatux-m is an antibody drug conjugate (ADC) that targets and inhibits growth of cancer cells overexpressing the epidermal growth factor receptor (EGFR) or the 2-7 deletion mutant (EGFRvIII) in tumor models in vitro and in vivo. Treatment of patients suffering from relapsed/refractory glioblastoma (GBM) with a combination of depatux-m and temozolomide (TMZ) tended to increase overall survival. As a first step to understand the nature of the interaction between the two drugs, we investigated whether the interaction was synergistic, additive or antagonistic.

METHODS

The efficacy of ADCs, antibodies, TMZ and radiation was tested in xenograft models of GBM, U-87MG and U-87MG EGFRvIII. Both models express EGFR. U-87MG EGFRvIII was transduced to express EGFRvIII. Changes in tumor volume, biomarkers of cell death and apoptosis after treatment were used to measure efficacy of the various treatments. Synergism of depatux-m and TMZ was verified in three-dimensional cultures of U-87MG and U-87MG EGFRvIII by the method of Chou and Talalay.

RESULTS

Combined with TMZ and radiotherapy (RT), depatux-m inhibited xenograft growth of U-87MG and U-87MG EGFRvIII more than either treatment with depatux-m or TMZ + RT. Durability of the response to depatux-m + TMZ + RT or depatux-m + TMZ was more pronounced in U-87MG EGFRvIII than in U-87MG. Efficacy of depatux-m + TMZ was synergistic in U-87MG EGFRvIII and additive in U-87MG.

CONCLUSION

Adding depatux-m enhances the efficacy of standard of care therapy in preclinical models of GBM. Durability of response to depatux-m + TMZ in vivo and synergy of the drug-drug interaction correlates with the amount of antigen expressed by the tumor cells.

Lipoxin (LTX A4 5S, 6R, 15R) levels drastically decrease after 5 years of hemodialysis treatment

The increased risk of atherosclerosis in patients with chronic kidney disease (CKD) is associated with the increased concentration of fatty acids from the omega-6 family. Products of arachidonic acid oxidation, including prostaglandins, thromboxanes, hydroxyleicosa-tetraenoic acids (HETES) and hydroxyoctadecadienoic acids (HODES) are involved in the pathogenesis of cancer and cardiovascular diseases due to increased oxidative stress. The aim of our study was to determine the relations resulting from the duration of CKD treatment. One of our main concerns is, whether and when the cascade of synthesis of inflammatory mediators may be insufficient in patients with CKD during many years of treatment. The study involved 121 patients with CKD and 87 healthy volunteers. Eicosanoid profiles 9(S)-HODE, 13(S)-HODE, 5(S)-HETE, 12(S)-HETE, 15(S)-HETE, 5(S)-oxoETE, 16(RS)-HETE, and 5(S),6(R)-lipoxinA4, 5(S),6(R),15(R)-lipoxinA4 were extracted in plasma. The HPLC separations were performed by means of 1260 liquid chromatography. Patients with CKD have a significantly higher concentration of the following inflammatory mediators: 13(S)-HODE, 5(S)-HETE, 12(S)-HETE, 15(S)-HETE, 5(S)-oxoETE, 16(RS)-HETE, and 5(S),6(R), 15(R)-lipoxinA4 relative to the control group. However, the concentrations of 9(S)-HODE were lower in the CKD group. The comparison of sexes did not show significant differences in terms of CKD. A tendency for lower concentrations of HETE and HODE were observed in the group of men. 15LOX, 12LOX and 5LOX pathways in chronic kidney disease are increased, while COX are suppressed (9-HODE). The analysis of the treatment time of patients with CKD shows that incorrect levels of 5(S), 6(R) and 15(R)-lipoxinA4 are developed. We present a new evidence of possible concepts and future clinical interventions in patients suffering from chronic kidney disease for many years. These data for the first time demonstrate that lipoxin levels drastically decrease in the course of CKD. Therefore, synthetic LXA4 analogues may be used as an antioxidant therapy in CKD, which requires further research.

Pharmacodynamic effects in blood and tumor tissue of eftozanermin alfa, a tumor necrosis factor-related apoptosis-inducing ligand receptor agonist

e15668

Background: Eftozanermin alfa (eftoza; formerly known as ABBV-621), a 2nd-generation tumor necrosis factor-related apoptosis-inducing ligand receptor agonist, is being evaluated in previously treated solid and hematologic malignancies (NCT03082209). In a dose-expansion cohort, patients (pts) with KRAS-mutant colorectal cancer (n = 24) and pancreatic cancer (n = 24) were evaluated at 3 dose levels with 12 mandatory paired biopsies per tumor type (pretreatment [Tx] and on-Tx collection). Following eftoza dosing, RNA and protein expression including posttranslational modifications were assessed in tumor biopsies to understand the target engagement and downstream pathway activation. Plasma was evaluated for changes in somatic mutant allele frequency and M30, M65 (circulating apoptotic markers). Methods: Biopsies were collected anytime during the screening period (pre-Tx) and 24±4 h following 2nd or 3rd infusion (on-Tx). Of the requested 4–6 fresh biopsy cores, 1–2 cores were collected as formalin fixed paraffin embedded (FFPE) and the rest were frozen tissue. FFPE tissue was analyzed by multiplex immunohistochemistry (IHC) and RNAseq; reverse phase protein array was used for frozen cores. Plasma was collected at cycle 1 predose and 2, 8, 24, 48, and 168 h postdose and analyzed for M30, M65 (by ELISA) and circulating tumor DNA (64-gene PlasmaSELECT assay). Results: Twenty-five pts consented to biopsies; paired biopsies were obtained from 16 pts at a 64% success rate: FFPE (n = 15) and frozen cores (n = 12). Tumor cells were detected in 11/15 (73%) FFPE and 4/12 (33%) frozen cores. Increase in M30, activated caspases, and cleaved PARP levels was observed in on-Tx biopsy samples compared with pre-Tx, thus serving as evidence for apoptosis induction in tumors following eftoza dosing. Changes in the tumor microenvironment were observed post-Tx by RNAseq and multiplex IHC (eg, CD68 level). Downregulation of prosurvival signaling pathways (eg, AKT/MEK) was also observed following eftoza dosing. Thirteen out of 16 pts showed transient increase in mutant allele fractions post eftoza Tx that correlated with increased plasma circulating tumor markers M30 and M65 at similar time points, suggesting activation of apoptosis pathway. Increase in M30, M65 levels also preceded increase in liver enzymes (ALT/AST) at 2, 48 hr post-Tx. Conclusions: Pharmacodynamic effect of eftoza was successfully demonstrated in blood and tumor tissue, including induction of apoptosis and modulation of PI3K and MEK signaling pathways. Clinical trial information: NCT03082209.

[Klinefelter'syndrome: A predisposition to sexual crime?]

BACKGROUND

Several studies have reported over-representation of psychiatric disorders among patients with Klinefelter' Syndrome (KS), with forensic complications.

OBJECTIVE

Consider determinants of sexual assault in patient with KS.

REVIEW

In this work, we present the case of Jules, 23 years old, with KS, benefiting from steroid replacement therapy, convicted of rape of a minor and evaluated in this context. We question here the role of his genetic pathology and of his hormonal treatment in this sexual assault.

FINDINGS

According to evidence from the literature, it is not possible to determine with certainty the fair value of each factor and their impact on the occurrence of the sexual criminal act. Indeed, although the crime rate among KS subjects is higher than in the general population, the majority of them have never been in trouble with the law; moreover, these subjects were no more likely to commit violent sexual acts than were criminals without KS. As for hormonal treatment, it seems that testosterone is better viewed as a facilitator of initiating an aggressive response than as a primary inductor.

CONCLUSION

In conclusion, the onset of sexual violence that accompanied the introduction of hormonal treatment into a patient with KS suggests an effective involvement of steroid replacement therapy, even small, in the criminal act. This must incite clinicians to extreme prudence and to take account of multidisciplinary expertise (psychiatrist, endocrinologist) in order to reconsider the continuation of the treatment in this particular forensic context. Finally, we discuss other factors that can precipitate such a violent act.

The short chain fatty acids and lipopolysaccharides status in Sprague-Dawley rats fed with high-fat and high-cholesterol diet

Short chain fatty acids (SCFA) are produced by the gut microbiota during the fermentation of non-digestible polysaccharides. Diet is a major factor driving the composition and metabolism of the colonic microbiota. The aim of our study was to examine how a fat-rich and cholesterol-rich diet that, which leads to many metabolic disorders, affects the SCFA profile and lipopolysaccharide (LPS) concentration. The experiment was carried out on 72 male, 8-weeks-old Sprague-Dawley rats. The study group (n = 30 rats) received high-fat and high cholesterol diet (HFHCh). The control group (n = 30) received standard food for laboratory rats. The rats from study and control groups were sacrificed after 4, 8, 12, 16 and 20 weeks after start of dietary exposure. The analysis of SFA in feces was performed using gas chromatography (Agilent Technologies 1260 A GC). The exposure to high-fat and high-cholesterol diet was associated with significant changes in SCFA levels. Relative to the control, each of HFHCh subgroup revealed a statistically significant decrease in butyrate (12.5% ± 5.7% versus 32.8% ± 9.1%) and an increase in propionate level (45.4% ± 6.2% versus 19.14% ± 7.1%). The ratio of acetate: propionate: butyrate was also changed (from 1.1: 0.6: 1 for control groups to 3 : 3,6 : 1 for HFHCh groups). The main SCFA in the HFHCh group was propionate instead of acetate. The dietary exposure resulted in significant differences in LPS concentration. After 12 weeks of HFD exposure, LPS concentration was significantly higher compared to control groups (P < 0.05). Our study showed that HFHCh diet affected butyrate and propionate production associated with an increase in LPS secretion. The hypothesis that observed changes could result in intestinal imbalance secondary to gut barrier dysfunction requires further studies.

Clinical pharmacodynamic/exposure characterisation of the multikinase inhibitor ilorasertib (ABT-348) in a phase 1 dose-escalation trial

Background

Ilorasertib (ABT-348) inhibits Aurora and VEGF receptor (VEGFR) kinases. Patients with advanced solid tumours participated in a phase 1 dose-escalation trial to profile the safety, tolerability, and pharmacokinetics of ilorasertib.

Methods

Ilorasertib monotherapy was administered at 10–180 mg orally once daily (Arm I, n = 23), 40–340 mg orally twice daily (Arm II, n = 28), or 8–32 mg intravenously once daily (Arm III, n = 7), on days 1, 8, and 15 of each 28-day cycle.

Results

Dose-limiting toxicities were predominantly related to VEGFR inhibition. The most frequent treatment-emergent adverse events ( > 30%) were: fatigue (48%), anorexia (34%), and hypertension (34%). Pharmacodynamic markers suggested that ilorasertib engaged VEGFR2 and Aurora B kinase, with the VEGFR2 effects reached at lower doses and exposures than Aurora inhibition effects. In Arm II, one basal cell carcinoma patient (40 mg twice daily (BID)) and one patient with adenocarcinoma of unknown primary site (230 mg BID) had partial responses.

Conclusions

In patients with advanced solid tumours, ilorasertib treatment resulted in evidence of engagement of the intended targets and antitumour activity, but with maximum inhibition of VEGFR family kinases occurring at lower exposures than typically required for inhibition of Aurora B in tissue.

Clinical Trial Registration: NCT01110486

Abstract P2-02-17: Circulating tumor DNA analysis with ultra-high sensitivity sequencing in metastatic breast cancer

Introduction.

Circulating tumor DNA analysis has the potential to transform the clinical management of patients with breast cancer. We assessed the accuracy of ultra-high sensitivity ctDNA testing in patients with advanced breast cancer.

Methods.

From a prospective tissue collection study, we identified 25 patients with a contemporaneous metastatic tissue biopsy and plasma for ctDNA testing. Tumour DNA from the metastatic tissue biopsy was sequenced with a validated clinical hybrid capture panel, while plasma cell free DNA was sequenced with AVENIO ctDNA technology – a molecular barcoded duplex sequencing based on CAPPseq technology. Sample collection is on-going and results from the full concordance series will be presented at the conference.

Results.

Circulating tumour DNA was detectable in 87% (20/23) of patients, with at least one variant from tissue sequencing identified in plasma. There was overall high agreement between tissue and plasma sequencing. The sensitivity of plasma testing for variants identified in tumour, positive percent agreement, was 75% (24/32). Plasma testing revealed a diversity of sub-clonal mutations including polyclonal ESR1, polyclonal FGFR2 and FGFR3 mutations, rare KRAS mutations, and TSC1 and MSH2 inactivating mutations.

Conclusions.

Circulating tumour DNA testing with molecular barcoded duplex sequencing offers high sensitivity for tumour variant detection. The extent of sub-clonal resistance mutations identified emphasises the genetic diversity of advanced breast cancer.

Citation Format: Garcia-Murillas I, Proszek P, Fribbens C, Yuan L, Bye H, Hubank M, Jiang J, Yuang S, Palma J, Johnston S, Ring A, Turner N. Circulating tumor DNA analysis with ultra-high sensitivity sequencing in metastatic breast cancer [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P2-02-17.

Effect of Propionibacterium acnes (PA) injection on intervertebral disc degeneration in a rat model: Does it mimic modic changes?

INTRODUCTION

Multiple reports of bacterial isolates in human disc tissue have suggested a role of low-grade infection on intervertebral disc degeneration and modic changes (MC) generation. Animal models have been extensively used to study IDD; however, until recently, no consideration had been given to eventual infectious processes. To reproduce the phenomena by inoculating an infecting agent would support the infectious hypothesis. Therefore, we studied the effect of Propionibacterium acnes (PA) inoculation on rat-tails and determined whether it would produce MCs on the adjacent endplates.

HYPOTHESIS

Disc infection with PA would accelerate IDD compared with the standard model and would also lead to MCs on the adjacent endplates.

METHODS

Twelve Sprague-Dawley rats were randomized to receive a needle puncture in a caudal tail disc with either saline (control) or an inoculum of 5×10⁷ CFU of strain 1a PA. Twelve weeks later, the rats were euthanized and the tails were analyzed. The main assessment criteria were obtained from the post-mortem MRI: T2 values of punctured discs and adjacent endplates, as well as disc volumes. A histological grading score for IDD was also used, measuring the morphology and cellularity of the nucleus and annulus, as well as endplate disruption.

RESULTS

The median T2 value and disc volume were smaller in PA-punctured discs [T2 value: 30ms (23-44) vs. 61ms (38-132), respectively, P=0.01; 0.01mm³ (0.01-0.05) vs. 0.5mm³ (0.01-5.35), respectively; P=0.049]. There was no change in the adjacent endplates. There was no significant difference in histological grading between the test and control [13 (10-14) vs. 10.5 (6-13); P=0.05].

DISCUSSION

Inoculation of caudal discs with PA generated increased degeneration; however, no MCs were observed on the adjacent endplates. A better understanding of low-grade disc infections is still needed.

LEVEL OF EVIDENCE

V (animal study).

Rugged constant-temperature thermal anemometer

Here we report a robust thermal anemometer which can be easily built. It was conceived to measure outdoor wind speeds and for airspeed monitoring in wind tunnels and other indoor uses. It works at a constant, low temperature of approximately 90 °C, so that an independent measurement of the air temperature is required to give a correct speed reading. Despite the size and high thermal inertia of the probe, the test results show that this anemometer is capable of measuring turbulent fluctuations up to ∼100 Hz in winds of ∼14 m/s, which corresponds to a scale similar to the length of the probe.

Macroscopic fibres of CNTs as electrodes for multifunctional electric double layer capacitors: from quantum capacitance to device performance

In this work we present a combined electrochemical and mechanical study of mesoporous electrodes based on CNT fibres in the context of electric double layer capacitors. We show that through control of the synthetic and assembly processes of the fibres, it is possible to obtain an active material that combines a surface area of 250 m(2) g(-1), high electrical conductivity (3.5 × 10(5) S m(-1)) and mechanical properties in the high-performance range including toughness (35 J g(-1)) comparable to that of aramid fibre (e.g. Kevlar). These properties are a consequence of the predominant orientation of the CNTs, observed by wide- and small-angle X-ray diffraction, and to the exceptionally long CNT length on the millimetre scale. Cyclic voltammetry measurements in a three-electrode configuration and using 1-butyl-3-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide (PYR14TFSI) ionic liquid electrolyte, show that the CNT fibres have a large quantum capacitance, evidenced by the near linear dependence of geometric capacitance (and conductivity) on potential bias. This reflects the low dimensionality of the CNT building blocks, which were purposely synthesised to have 1-5 layers and a high degree of graphitization. From the charge-discharge measurements of supercapacitor devices with symmetric CNT fibre electrodes we obtain power and energy densities as high as 58 kW kg(-1) and 14 Wh kg(-1), respectively. These record-high values for CNT fibre-based supercapacitors, are a consequence of the low equivalent series resistance due to the high conductivity of the fibres, the large contribution from quantum capacitance, and the wide stability window of the ionic liquid (3.5 V). Cycle life experiments demonstrate stable capacitance and energy retention over 10,000 cycles of charge-discharge at 3.5 V.

Membrane-less organic–inorganic aqueous flow batteries with improved cell potential

A new organic–inorganic membrane-less flow battery based on low cost materials with stable performance.

Seahorse (Hippocampinae) population fluctuations in the Ria Formosa Lagoon, south Portugal

Comparisons of three sets of surveys in the Ria Formosa Lagoon, Portugal, over a 13 year period (2001-2002, 2008-2009 and 2010-2013) revealed significant population fluctuations in at least one of the two seahorse (Hippocampinae) species living there, and that those fluctuations were potentially associated with habitat changes in the lagoon. After a significant decline between the first two survey periods (2001-2002 v. 2008-2009), long-snouted seahorse Hippocampus guttulatus populations increased significantly between 2008-2009 surveys and new 2010-2013 surveys. There were no significant differences in H. guttulatus populations between the 2001-2002 and 2010-2013 surveys. In contrast, there were no significant differences in short-snouted seahorse Hippocampus hippocampus densities among the 16 sites surveyed throughout the three sampling periods, although the ability to detect any change was hampered by the low densities of this species in all time periods. Fluctuations in H. guttulatus densities were positively correlated with the percentage of holdfast coverage, but with none of the other environmental variables tested. These results highlight the importance of holdfast availability in maintaining stable seahorse populations. While population fluctuations are certainly more promising than a consistent downward decline, such extreme fluctuations observed for seahorses in the Ria Formosa Lagoon could still leave these two species vulnerable to any additional stressors, particularly during low density periods.

The effect of diet on ontogenic development of the digestive tract in juvenile reared long snout seahorse Hippocampus guttulatus

Ontogenetic development of the digestive tract and associated organs in long snout seahorse Hippocampus guttulatus juveniles was morphologically and histologically examined from the time of release from the male's pouch until 72 h after the first meal. When released from the male's pouch, juvenile seahorses are small adult replicates. This means that unlike other teleost fish larvae, the first developmental phase has already taken place, and juveniles are morphologically prepared and able to feed on live prey immediately following parturition. At this stage, the buccopharynx, oesophagus, and intestine already appear to be fully developed. The intestine is divided into the midgut and hindgut by an intestinal valve, and intestinal villi are visible in the midgut. When fed with DHA-Selco(®) enriched Artemia, H. guttulatus juveniles developed a severe condition of overinflation of the gas bladder. The continuous overinflation of the gas bladder forced air into the gut (48 h after the first meal), resulting in overinflation of both the gut and the gas bladder (72 h after the first meal), and death occurred within 120 h after the first meal. When fed natural copepods, H. guttulatus juveniles continued a normal feeding activity with no signs of intestinal disorders, and the gas bladder and intestine maintained their normal shape. This is the first study to positively associate gas bladder overinflation of juvenile seahorses with nutritionally unbalanced diets, and not to gas supersaturation alone. It is therefore necessary to develop more adequate feed and/or enrichment products to improve the survival of juvenile seahorses in captivity.

The use of a non-invasive tool for capture-recapture studies on a seahorse Hippocampus guttulatus population

In this study, the spot pattern in Hippocampus guttulatus was analysed using a computer programme algorithm that allowed individual comparison. This methodology was first tested in a controlled environment using 51 adult and 55 juvenile H. guttulatus. Positive matches were obtained in 86·3 and 83·6% of the adults and juveniles, respectively. In a second experiment, monthly surveys were carried out in five selected locations in the Ria Formosa Lagoon, south Portugal, over the course of a year and a total of 980 photographs were analysed. Photographed H. guttulatus were re-sighted one to nine times during the course of the survey period with an overall re-sight record of over 30%. Photo-identification was therefore shown to be a useful tool for non-invasive mark-recapture studies that can be successfully used to survey the population abundance of H. guttulatus aged 6 months or older in consecutive years. This could be of great value when considering the assessment of H. guttulatus populations and understanding changes over time.

Photoelectrocatalytic study and scaling up of titanium dioxide electrodes for wastewater treatment

Different TiO2 photoelectrodes have been characterized and tested for the photoelectrocatalytic oxidation of methanol. Particulate electrodes (TiO2/Ti and TiO2/ITO) have been shown to notably favour charge-carrier transfer at the electrolyte interface while a thermal electrode (Ti) has been shown to favour charge-carrier separation when applying an electric potential bias according to cyclic voltammetry technique, as a consequence of differences in TiO2 surface between particulate and thermal electrodes. Particulate electrodes lead to a higher photoelectrocatalytic activity for methanol oxidation compared to that of the thermal electrode, probably due to the pure-rutile TiO2 phase composition of the latter and its lower surface area. TiO2/Ti electrode has been shown to be the most effective photoelectrode tested for methanol oxidation since its activity was improved by the combination of the particulate TiO2 layer and the high electrical conductivity of the support. Generally, photocurrent density measured in the photoelectrochemical cell seems to correlate with activity, whereas this correlation is not observed when using a larger photoelectrocatalytic reactor. In contrast, the activity obtained for the scaled-up electrode is found to be similar in terms of surface kinetic constant to that obtained at laboratory scale.

Abstract 1818: The Aurora B inhibitor ABT-348 is not susceptible to known resistance mechanisms of other Aurora B inhibitors

The Aurora kinases (Aurora A, B, and C) play essential roles in regulating cell division in mammalian cells and their over-expression in diverse tumor types makes them appealing oncology targets. ABT-348 is a novel, ATP-competitive, multi-targeted kinase inhibitor that exhibits potent activity in multiple solid tumor-derived and leukemia cell lines. ABT-348 is active against Aurora B (IC50 7 nM) and Aurora C (IC50 1 nM), Aurora A (IC50 120 nM). The activity against Aurora B is demonstrated by inhibition of histone H3 phosphorylation and induction of polyploidy. ABT-348 is also active against Aurora-B Y156H, a mutant resistant to other Aurora-B inhibitors. In addition, ABT-348 potently inhibits most members of the VEGFR and PDGFR family of receptor tyrosine kinases, which play a critical role in stromal angiogenesis. In contrast to other Aurora kinase inhibitors, the cellular efficacy of ABT-348 is retained in cells over-expressing P-glycoprotein (Pgp) or breast cancer resistant protein (BCRP), indicating that ABT-348 is not a substrate for these commonly upregulated ATP-binding cassette drug transporters. Consistent with these in vitro studies, ABT-348 was broadly efficacious as a single agent against a wide range of tumor types in vivo, including 3 multi-drug resistant xenograft models. In summary, the potent activity and unique kinase selectivity of ABT-348 against the Aurora kinases and VEGF and PDGF receptor tyrosine kinases, engender its ability to block multiple mechanisms of tumor progression. In addition, our data provide evidence that ABT-348 may be active in tumors resistant to other well-characterized inhibitors targeting Aurora-B. ABT-348 is presently under clinical evaluation in adult patients with advanced solid and hematological neoplasms.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 1818. doi:1538-7445.AM2012-1818

Advances in tagging syngnathids, with the effects of dummy tags on behaviour of Hippocampus guttulatus

Artificial marking and tagging techniques have been used to study movement, population dynamics, behaviour, ecology, survival and growth of at least 25 syngnathid species. External necklace-style tags and injection of visible implant elastomer have been the most used techniques, uniquely identifying hundreds of individual syngnathids to study population dynamics, mortality, behaviour, ecology and growth in at least 13 and 12 species, respectively. Only two studies, both on larger syngnathid species, have tested the use of internal or electronic tags. This new case study reveals that dummy tags, weighing up to 6% of individual body mass, have minimal effect on normal ex situ behaviour of the long-snouted seahorse Hippocampus guttulatus, a smaller syngnathid. In paired aquarium trials, tags did not affect movement, holdfast use or general behavioural state, and only had a short-term effect (1 day) on vertical orientation. Tagged H. guttulatus gained more mass during the 5 day trials, a result which warrants further exploration but indicates that tags did not reduce feeding. This study shows promise for using electronic tagging to study H. guttulatus and similarly sized syngnathids in the wild.

Mobilization and collection of peripheral blood stem cells: guidelines for blood volume to process, based on CD34-positive blood cell count in adults and children

We report 189 mobilizations and 489 collections of peripheral blood stem cells (PBSC) performed in 139 autologous transplantation patients and in 28 donors for allogeneic transplantations whose ages ranged from 2-68 years. We observed a correlation (P < .001; Pearson's coefficient 0.64) between CD34-positive cells and granulocyte-macrophage colony-forming units examined to estimate PBSC. In a subset of 287 collections (97 adults and 49 children) we obtained peripheral blood (PB) CD34-positive cell counts at 2 to 4 hours before leukapheresis. We noted a correlation between PB CD34-positive cell counts before leukapheresis and the number of CD34-positive cells per kilogram of body weight collected in the whole apheresis of the day (P < .001; Pearson's coefficient 0.82). An even better correlation was obtained between PB CD34-positive cells preapheresis and the yield of each individual blood volume (BV) processed (P < .001; Pearson's coefficient 0.87). Healthy donors and patients in each age group behaved similarly. In addition, the collection yield was greater among children than adults. These findings allowed us to develop a simple predictive model to estimate the BV to process for a target dose of CD34-positive cells per kilogram, based on the level of PBSC before apheresis in children and adults.

Right ventricular beneficial effects of intracoronary SERCA2a gene transfer in an experimental model of heart failure

SERCA2a gene transfer ameliorates heart failure pathologic processes in left ventricular myocardium. We sought to assess the simultaneous molecular changes that occur in the right ventricle. Sprague-Dawley rats underwent aortic banding and were followed by echocardiography for development of heart failure. After a decrease in fractional shortening of 25 % from baseline, intracoronary injection of adenoviral-SERCA2a or adenoviral-beta-galactosidase was performed. Successful gene transfer was confirmed by immunoblotting. Rats were randomly euthanized on post-operative day 7 or 21. Protein analysis including right ventricular levels of SERCA2a, betaARK1, inflammatory mediators (IL-1, IL-6 and TNF-alpha), apoptotic markers (Bax, Bak and Bcl-2) and MAPK (Jnk, p38 and Erk) was performed. Adenoviral-SERCA2a-treated animals showed increased right ventricular expression of SERCA2a compared with controls. Decreased levels of inflammatory markers were also demonstrated in this group. Expression of pro-apoptotic markers was similarly improved. Levels of MAPK were increased compared with the control group. These differences were most significant 7 days after gene transfer, but the majority of these changes persisted at 21 days. These results suggest that attenuation of pathologic mechanisms of calcium cycling, inflammation and apoptosis also occur in the right ventricular myocardium after SERCA2a gene transfer during heart failure. These findings support a therapeutic role for genetic manipulation of this pathway in patients with right ventricular or biventricular failure.

Abstract A161: Acquired resistance to combination treatment with TMZ and ABT-888 is mediated by both BER and HR DNA repair pathways

Many established cancer therapies involve DNA-damaging chemotherapy or radiotherapy. Gain of DNA repair capacity of the tumor represents a common mechanism employed by cancer cells to survive DNA-damaging therapy. Poly (ADP-ribose) polymerase-1 (PARP-1) is a nuclear enzyme that is activated by DNA-damage and plays a critical role in base excision repair (BER). Inhibition of PARP represents an attractive approach for the treatment of cancer. Previously, we have described the discovery and characterization of a potent PARP inhibitor, ABT-888. ABT-888 potentiates the activity of DNA-damaging agents such as temozolomide (TMZ) in a variety of preclinical models. Previously, we demonstrated that ABT-888 potentiated the cytotoxic effect of TMZ by converting TMZ-induced single strand DNA breaks (SSB) to double strand breaks (DSB). We report here the generation of HCT116 cells resistant to treatment with TMZ and ABT-888 (HCT116R cells). HCT116R cells exhibit decreased H2AX phosphorylation in response to the treatment with TMZ and ABT-888 relative to parental HCT116 cells. Microarray and western blot studies indicate that HCT116R cells have decreased PARP-1 and elevated Rad51 expression levels. HCT116R cells are dependent on Rad51 for proliferation and survival, as demonstrated by inhibition of proliferation and induction of apoptosis upon treatment with Rad51 siRNA. In addition, HCT116R cells are more resistant to radiation than the parental HCT116 cells. Our study suggests that cancer cells up-regulate the homologous recombination DNA repair pathway to compensate for the loss of BER, which may account for the observed resistance to the treatment with TMZ and ABT-888.

Citation Information: Mol Cancer Ther 2009;8(12 Suppl):A161.

Acquired resistance to combination treatment with temozolomide and ABT-888 is mediated by both base excision repair and homologous recombination DNA repair pathways

Many established cancer therapies involve DNA-damaging chemotherapy or radiotherapy. Gain of DNA repair capacity of the tumor represents a common mechanism used by cancer cells to survive DNA-damaging therapy. Poly(ADP-ribose) polymerase-1 (PARP-1) is a nuclear enzyme that is activated by DNA damage and plays a critical role in base excision repair. Inhibition of PARP represents an attractive approach for the treatment of cancer. Previously, we have described the discovery and characterization of a potent PARP inhibitor, ABT-888. ABT-888 potentiates the activity of DNA-damaging agents such as temozolomide (TMZ) in a variety of preclinical models. We report here the generation of HCT116 cells resistant to treatment with TMZ and ABT-888 (HCT116R cells). HCT116R cells exhibit decreased H2AX phosphorylation in response to treatment with TMZ and ABT-888 relative to parental HCT116 cells. Microarray and Western blot studies indicate that HCT116R cells have decreased PARP-1 and elevated Rad51 expression levels. HCT116R cells are dependent on Rad51 for proliferation and survival, as shown by inhibition of proliferation and induction of apoptosis upon treatment with Rad51 small interfering RNA. In addition, HCT116R cells are more resistant to radiation than the parental HCT116 cells. Our study suggests that cancer cells upregulate the homologous recombination DNA repair pathway to compensate for the loss of base excision repair, which may account for the observed resistance to treatment with TMZ and ABT-888.