Cucurbit[n]uril binding of platinum anticancer complexes

The encapsulation of cisplatin by cucurbit[7]uril (Q[7]) and multinuclear platinum complexes linked via a 4,4′-dipyrazolylmethane (dpzm) ligand by Q[7] and cucurbit[8]uril (Q[8]) has been studied by NMR spectroscopy and molecular modelling. The NMR studies suggest that some cisplatin binds in the cucurbituril cavity, while cis-[PtCl(NH3)2(H2O)]+ only binds at the portals. Alternatively, the dpzm-linked multinuclear platinum complexes are quantitatively encapsulated within the cavities of both Q[7] and Q[8]. Upon encapsulation, the non-exchangeable proton resonances of the multinuclear platinum complexes show significant upfield shifts in 1H NMR spectra. The H3/H3* resonances shift upfield by 0.08 to 0.55 ppm, the H5/H5* shift by 0.9 to 1.6 ppm, while the methylene resonances shift by 0.74 to 0.88 ppm. The size of the resonance shift is dependent on the cavity size of the encapsulating cucurbituril, with Q[7] encapsulation producing larger shifts than Q[8]. The upfield shifts of the dpzm resonances observed upon cucurbituril encapsulation indicate that the Q[7] or Q[8] is positioned directly over the dpzm linking ligand. The terminal platinum groups of trans-[{PtCl(NH3)2}2μ-dpzm]2+ (di-Pt) and trans-[trans-{PtCl(NH3)2}2-trans-{Pt(dpzm)2(NH3)2}]4+ (tri-Pt) provide a barrier to the on and off movement of cucurbituril, resulting in binding kinetics that are slow on the NMR timescale for the metal complex. Although the dpzm ligand has relatively few rotamers, encapsulation by the larger Q[8] resulted in a more compact di-Pt conformation with each platinum centre retracted further into each Q[8] portal. Encapsulation of the hydrolysed forms of di-Pt and tri-Pt is considerably slower than for the corresponding Cl forms, presumably due to the high-energy cost of passing the +2 platinum centres through the cucurbituril portals. The results of this study suggest that cucurbiturils could be suitable hosts for the pharmacological delivery of multinuclear platinum complexe

High-Load Reovirus Infections Do Not Imply Physiological Impairment in Salmon

The recent ubiquitous detection of PRV among salmonids has sparked international concern about the cardiorespiratory performance of infected wild and farmed salmon. Piscine orthoreovirus (PRV) has been shown to create substantial viremia in salmon by targeting erythrocytes for principle replication. In some instances, infections develop into heart and skeletal muscle inflammation (HSMI) or other pathological conditions affecting the respiratory system. Critical to assessing the seriousness of PRV infections are controlled infection studies that measure physiological impairment to critical life support systems. Respiratory performance is such a system and here multiple indices were measured to test the hypothesis that a low-virulence strain of PRV from Pacific Canada compromises the cardiorespiratory capabilities of Atlantic salmon. Contrary to this hypothesis, the oxygen affinity and carrying capacity of erythrocytes were unaffected by PRV despite the presence of severe viremia, minor heart pathology and transient cellular activation of antiviral response pathways. Similarly, PRV-infected fish had neither sustained nor appreciable differences in respiratory capabilities compared with control fish. The lack of functional harm to salmon infected with PRV in this instance highlights that, in an era of unprecedented virus discovery, detection of viral infection does not necessarily imply bodily harm and that viral load is not always a suitable predictor of disease within a host organism

Self-management education for cystic fibrosis

Background: Self-management education may help patients with cystic fibrosis and their families to choose, monitor and adjust treatment requirements for their illness, and also to manage the effects of illness on their lives. Although self-management education interventions have been developed for cystic fibrosis, no previous systematic review of the evidence of effectiveness of these interventions has been conducted. Objectives: To assess the effects of self-management education interventions on improving health outcomes for patients with cystic fibrosis and their caregivers. Search methods: We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group Trials Register (date of the last search: 22 August 2013). We also searched databases through EBSCO (CINAHL; Psychological and Behavioural Sciences Collection; PsychInfo; SocINDEX) and Elsevier (Embase) and handsearched relevant journals and conference proceedings (date of the last searches: 01 February 2014 ). Selection criteria: Randomised controlled trials, quasi-randomised controlled trials or controlled clinical trials comparing different types of self-management education for cystic fibrosis or comparing self-management education with standard care or no intervention. Data collection and analysis: Two authors assessed trial eligibility and risk of bias. Three authors extracted data. Main results: Four trials (involving a total of 269 participants) were included. The participants were children with cystic fibrosis and their parents or caregivers in three trials and adults with cystic fibrosis in one trial. The trials compared four different self-management education interventions versus standard treatment: (1) a training programme for managing cystic fibrosis in general; (2) education specific to aerosol and airway clearance treatments; (3) disease-specific nutrition education; and (4) general and disease-specific nutrition education. Training children to manage cystic fibrosis in general had no statistically significant effects on weight after six to eight weeks, mean difference -7.74 lb (i.e. 3.51 kg) (95% confidence interval -35.18 to 19.70). General and disease-specific nutrition education for adults had no statistically significant effects on: pulmonary function (forced expiratory volume at one second), mean difference -5.00 % (95% confidence interval -18.10 to 8.10) at six months and mean difference -5.50 % (95% confidence interval -18.46 to 7.46) at 12 months; or weight, mean difference - 0.70 kg (95% confidence interval -6.58 to 5.18) at six months and mean difference -0.70 kg (95% confidence interval -6.62 to 5.22) at 12 months; or dietary fat intake scores, mean difference 1.60 (85% confidence interval -2.90 to 6.10) at six months and mean difference 0.20 (95% confidence interval -4.08 to 4.48) at 12 months. There is some limited evidence to suggest that self-management education may improve knowledge in patients with cystic fibrosis but not in parents or caregivers. There is also some limited evidence to suggest that self-management education may result in positively changing a small number of behaviours in both patients and caregivers. Authors' conclusions: The available evidence from this review is of insufficient quantity and quality to draw any firm conclusions about the effects of self-management education for cystic fibrosis. Further trials are needed to investigate the effects of self-management education on a range of clinical and behavioural outcomes in children, adolescents and adults with cystic fibrosis and their caregivers

Self-management education for cystic fibrosis

Self-management education may help patients with cystic fibrosis and their families to choose, monitor and adjust treatment requirements for their illness, and also to manage the effects of illness on their lives. Although self-management education interventions have been developed for cystic fibrosis, no previous systematic review of the evidence of effectiveness of these interventions has been conducted

A rapid intrinsic heart rate resetting response with thermal acclimation in rainbow trout, Oncorhynchus mykiss.

We examined cardiac pacemaker rate resetting in rainbow trout following a reciprocal temperature transfer. In the original experiment, performed in winter, 4°C-acclimated fish transferred to 12°C reset intrinsic heart rate after just 1 h (from 56.8±1.2 to 50.8±1.5 beats min-1); 12°C-acclimated fish transferred to 4°C reset intrinsic heart rate after 8 h (from 33.4±0.7 to 37.7±1.2 beats min-1). However, in a replicate experiment, performed in the summer using a different brood year, intrinsic heart rate was not reset, even after 10 weeks at a new temperature. Using this serendipitous opportunity, we compared mRNA expression changes of a suite of proteins in sinoatrial node (SAN), atrial and ventricular tissues after both 1 h and longer than 3 weeks for both experimental acclimation groups to identify those changes only associated with pacemaker rate resetting. Of the changes in mRNA expression occurring after more than 3 weeks of warm acclimation and associated with pacemaker rate resetting, we observed downregulation of NKA α1c in the atrium and ventricle, and upregulation of HCN1 in the ventricle. However, in the SAN there were no mRNA expression changes unique to the fish with pacemaker rate resetting after either 1 h or 3 weeks of warm acclimation. Thus, despite identifying changes in mRNA expression of contractile cardiac tissues, there was an absence of changes in mRNA expression directly involved with the initial, rapid pacemaker rate resetting with warm acclimation. Importantly, pacemaker rate resetting with thermal acclimation does not always occur in rainbow trout.This work is supported by the Natural Science and Engineering Research Council (NSERC) Discovery Grant 2015-05059 to A.P.F. who holds a Canada Research Chair (Tier I)