A Novel Prebiotic Fibre Blend Supports the Gastrointestinal Health of Senior Dogs

Senior pets can suffer from a wide range of age-related diseases that can impact the quality of life for the pet and the relationship between a pet and their owner. Dietary fibre plays a key role in shaping the gastrointestinal health in mammalian species. The aim of this study was to investigate the impact of a novel prebiotic fibre blend containing sugar beet pulp, galacto-oligosaccharides, and cellulose on the health of senior dogs when fed on top of a background commercial dry diet. Thirty-two dogs aged >8 years received the prebiotic fibre blend as a dietary topper for 21 days on top of a nutritionally complete diet using a cross-over study design. The prebiotic fibre blend improved the gastrointestinal health of senior dogs as measured through improved faecal quality scores, a reduction in faecal pH, changes to the taxonomic composition of the gut, and a reduction in faecal branched-chain fatty acids, which are markers for proteolytic degradation. Broader systemic measures, such as changes to serum cytokines, were not impacted by the prebiotic fibre blend. In conclusion, a novel prebiotic fibre blend containing sugar beet pulp, galacto-oligosaccharides, and cellulose improved the gastrointestinal health of senior dogs and could have a range of potential future dietary applications.

Higher Anti-tumor Necrosis Factor-α Levels Correlate With Improved Radiologic Outcomes in Crohn's Perianal Fistulas

BACKGROUND & AIMS

Higher anti-tumor necrosis factor-α (TNF) drug levels are associated with improved clinical healing of Crohn's perianal fistulas. It is unclear whether this leads to improved healing on radiologic assessment. We aimed to evaluate the association between anti-TNF drug levels and radiologic outcomes in perianal fistulising Crohn's disease.

METHODS

A cross-sectional retrospective multicenter study was undertaken. Patients with perianal fistulising Crohn's disease on maintenance infliximab or adalimumab, with drug levels within 6 months of perianal magnetic resonance imaging were included. Patients receiving dose changes or fistula surgery between drug level and imaging were excluded. Radiologic disease activity was scored using the Van Assche Index, with an inflammatory subscore calculated using indices: T2-weighted imaging hyperintensity, collections >3 mm diameter, rectal wall involvement. Primary endpoint was radiologic healing (inflammatory subscore ≤6). Secondary endpoint was radiologic remission (inflammatory subscore = 0).

RESULTS

Of 193 patients (infliximab, n = 117; adalimumab, n = 76), patients with radiologic healing had higher median drug levels compared with those with active disease (infliximab 6.0 vs 3.9 μg/mL; adalimumab 9.1 vs 6.2 μg/mL; both P < .05). Patients with radiologic remission also had higher median drug levels compared with those with active disease (infliximab 7.4 vs 3.9 μg/mL; P < .05; adalimumab 9.8 vs 6.2 μg/mL; P = .07). There was a significant incremental reduction in median inflammatory subscores with higher anti-TNF drug level tertiles.

CONCLUSIONS

Higher anti-TNF drug levels were associated with improved radiologic outcomes on magnetic resonance imaging in perianal fistulising Crohn's disease, with an incremental improvement at higher drug level tertiles for both infliximab and adalimumab.

Faecal microbiota transplant to ERadicate gastrointestinal carriage of Antibiotic Resistant Organisms (FERARO): a prospective, randomised placebo-controlled feasibility trial

INTRODUCTION

Antimicrobial resistance is rising, largely due to the indiscriminate use of antimicrobials. The human gut is the largest reservoir of antibiotic resistant bacteria (ARB). Individuals colonised with ARB have the potential to spread these organisms both in the community and hospital settings. Infections with ARB such as extended spectrum beta-lactamase producing enterobacteriales (ESBL-E) and carbapenemase producing enterobacteriales (CPE) are more difficult to treat and are associated with an increased morbidity and mortality. Presently, there is no effective decolonisation strategy for these ARB. Faecal microbiota transplant (FMT) has emerged as a potential strategy for decolonisation of ARB from the human gut, however there is significant uncertainty about the feasibility, effectiveness and safety of using this approach.

METHODS AND ANALYSIS

Prospective, randomised, patient-blinded, placebo-controlled feasibility trial of FMT to eradicate gastrointestinal carriage of ARB. Eighty patients with a recent history of invasive infection secondary to ESBL-E or CPE and persistent gastrointestinal carriage will be randomised 1:1 to receive encapsulated FMT or placebo. The primary outcome measure is consent rate (as a proportion of patients who fulfil inclusion/exclusion criteria); this will be used to determine if a substantive trial is feasible. Participants will be followed up at 1 week, 1 month, 3 months and 6 months and monitored for adverse events as well as gastrointestinal carriage rates of ARB after intervention.

ETHICS AND DISSEMINATION

Research ethics approval was obtained by London-City and East Research Ethics Committee (ref 20/LO/0117). Trial results will be published in a peer-reviewed journal and presented at international conferences.

TRIAL REGISTRATION NUMBER

ISRCTN registration number 34 467 677 and EudraCT number 2019-001618-41.

Disease-induced changes in alpha-adrenoceptor-mediated cardiac and vascular responses in rats

1. The physiological relevance of cardiac and vascular alpha-adrenoceptors may increase in disease states in which beta-adrenoceptors are altered. To test this, positive inotropic and vasoconstrictor responses to phenylephrine were measured in isolated tissues from rats with experimentally-induced hyperthyroidism, hypothyroidism and diabetes as well as in genetically spontaneous hypertensive rats (SHR). 2. In left atria, positive inotropic responses to phenylephrine were increased in hypothyroid and diabetic rats and abolished in hyperthyroid and SHR. 3. In contrast, phenylephrine produced increased positive inotropy in left ventricular papillary muscles from hyperthyroid rats, increased potency in diabetic rats and negative inotropic responses in hypothyroid rats. 4. The potency of phenylephrine as a vasoconstrictor in thoracic aortic rings was increased in hyperthyroid and SHR and decreased in hypothyroid rats. 5. Thus, disease states which alter beta-adrenoceptor responsiveness can independently regulate atrial, ventricular and vascular responses to the alpha 1-adrenoceptor agonist, phenylephrine. Therefore, these disease states may alter the physiological control of the cardiovascular system by noradrenaline and adrenaline as well as the responsiveness in disease states to therapeutic agents acting via alpha-adrenoceptors.

Beta-adrenoceptor antagonism and the hyperthyroid rat heart

beta-Adrenoceptor antagonists such as propranolol and atenolol ameliorate the symptoms of human hyperthyroidism. We wished to define whether the cardiac changes of hyperthyroidism are attenuated by treatment with the beta-adrenoceptor antagonist atenolol. Rats were treated with triiodothyronine (T3) [1 mg/kg/day subcutaneously (s.c.) for 14 days] together with oral atenolol (100 mg/day on days 8-14); physiological parameters, inotropic and chronotropic responses in isolated cardiac tissues to compounds that increase intracellular cyclic AMP, and ventricular beta 1- and beta 2-adrenoceptors were measured. Administration of T3 produced marked hyperthyroidism, leading to increased metabolism, cardiac hypertrophy, tachycardia, hypertension, marked decrease in or loss of positive inotropic responses to calcium chloride, norepinephrine (NE), forskolin, and theophylline and increased ventricular beta 1- and beta 2-adrenoceptor density. Atenolol treatment of hyperthyroid rats attenuated the increases in heart rate (HR), rectal temperature, and O2 consumption but did not alter cardiac hypertrophy, hypertension, decreased positive inotropic responses or increased beta-adrenoceptor density. We conclude that beta-adrenoceptor antagonists produce only limited changes in hyperthyroidism-induced cardiovascular responses; furthermore, beta-adrenoceptor antagonists are unlikely to attenuate the cardiovascular risk factors of hyperthyroidism.

A randomized double-blind trial of vancomycin versus teicoplanin for the treatment of gram-positive bacteremia in patients with cancer

In a prospective, randomized, double-blind study comparing teicoplanin and vancomycin for the treatment of gram-positive bacteremias in neutropenic patients, teicoplanin was given at 6 mg/kg of body weight every 24 h intravenously (i.v.) after initial loading every 12 h for three doses, while vancomycin was administered at 15 mg/kg every 12 h i.v. At enrollment, both groups were comparable in age, sex, underlying hematologic or neoplastic disorder, baseline renal functions, and incidence of neutropenia. Treatment was successful in 19 (90%) of 21 patients who received teicoplanin and 24 (96%) of 25 who received vancomycin (P = .58). Adverse reactions occurred more often in the vancomycin group (31%) than in the teicoplanin group (9%; P = .06) and were primarily cutaneous or gastrointestinal. In conclusion, teicoplanin was better tolerated than vancomycin, and no statistically significant difference in efficacy was detected with the sample size in this study.

Transient outward current in human and rat ventricular myocytes

OBJECTIVE

The aim was to investigate transient outward currents (I(to)) in single myocytes isolated from human heart muscle specimens which were obtained either from patients in terminal heart failure receiving a transplant or from multiorgan donors whose hearts were not suitable for transplantation.

METHODS

Using the whole cell patch clamp technique, depolarisation dependent I(to) was investigated in these myocytes, and its electrophysiological characteristics compared to I(to) of rat myocytes.

RESULTS

I(to) was observed in ventricular myocytes isolated from failing and non-failing human hearts. The current density of I(to) was similar in cells from failing and non-failing hearts [at +60 mV: 7.9(SEM 1.0) pA.pF-1, n = 9, and 8.7(1.2) pA.pF-1, n = 8, respectively], but smaller in human than in normal rat myocytes, ie, 8.2(0.7) pA.pF-1 (n = 17) v 19.9(2.8) pA.pF-1 (n = 12, six hearts), respectively. Half maximum activation was found at more positive potentials in human than in rat cells, at +21.2(2.0) v +6.4(1.3) mV. In human myocytes, the fraction of non-inactivating outward current at the end of 300 ms long clamp steps was smaller than in rat cells, ie, 22(5%) of peak I(to) in human (n = 17) and 39(5%) in rat cells (n = 12). The potential of half maximum steady state inactivation of rapidly inactivating I(to) in the presence of 0.1 mM Cd2+ was -21.4(0.7) mV in human (n = 15, five hearts), and -35.3(1.0) mV in rat cells (n = 12, six hearts). The late component of outward current showed no potential dependent inactivation in human cells, but underwent steady state inactivation at all potentials positive to -100 mV in rat myocytes. At -100 mV, recovery of I(to) from inactivation took place with a similar time constant, ie, 18(2) ms (n = 7), 24(2) ms (n = 6), and 25(2) ms (n = 4) in cells from three failing and two non-failing human hearts, and from two normal rat hearts, respectively.

CONCLUSIONS

In a limited number of cells, I(to) in human ventricular myocytes shows no dramatic differences between cells derived from failing and non-failing hearts. The characteristics of I(to) in human cells were similar though not identical to I(to) in rat heart cells. This current may be a potential target for antiarrhythmic drug action.