Immunogenicity of an AS01-adjuvanted respiratory syncytial virus prefusion F (RSVPreF3) vaccine in animal models

Respiratory syncytial virus (RSV) causes a high disease burden in older adults. An effective vaccine for this RSV-primed population may need to boost/elicit robust RSV-neutralizing antibody responses and recall/induce RSV-specific T cell responses. To inform the selection of the vaccine formulation for older adults, RSVPreF3 (RSV fusion glycoprotein engineered to maintain the prefusion conformation) with/without AS01 adjuvant was evaluated in mice and bovine RSV infection-primed cattle. In mice, RSVPreF3/AS01 elicited robust RSV-A/B-specific neutralization titers and RSV F-specific polyfunctional CD4+ T cell responses exceeding those induced by non-adjuvanted RSVPreF3. In primed bovines, RSVPreF3/AS01 tended to induce higher pre-/post-vaccination fold-increases in RSV-A/B-specific neutralization titers relative to non-adjuvanted and Alum-adjuvanted RSVPreF3 formulations, and elicited higher RSV F-specific CD4+ T cell frequencies relative to the non-adjuvanted vaccine. Though AS01 adjuvanticity varied by animal species and priming status, RSVPreF3/AS01 elicited/boosted RSV-A/B-specific neutralization titers and RSV F-specific CD4+ T cell responses in both animal models, which supported its further clinical evaluation as prophylactic candidate vaccine for older adults.

Chronic effects of a binary insecticide Acer 35 EC on Nile tilapia Oreochromis niloticus through a multi-biomarker approach

Acer 35 EC is a widely used insecticide (a binary mixture of lambda-cyhalothrin and acetamiprid) in pest control in many West African countries, particularly in the cotton culture in north Benin. The aim of this study was to investigate the chronic effects of Acer 35 EC on Nile tilapia Oreochromis niloticus juveniles using a multi-biomarker approach under laboratory conditions. For this purpose, fish were exposed to sublethal concentrations of Acer 35 EC (0, 1 and 10% of LC₅₀- 96 h value). After 28 and 56 days of exposure, several biomarkers were measured in males and females including enzymatic activities related to detoxification and oxidative stress, neurotoxicity and immune responses, sex steroid hormones (testosterone, 17β-estradiol and 11-keto-testosterone) and histological alterations of liver, kidney and gonads. An Integrated Biomarker Response (IBR) was then calculated. The results showed a reduction of cholinesterase activity in muscles, and intercellular superoxide anion production in both sexes. Female steroidogenesis and gametogenesis were affected, especially testosterone levels and oocyte growth. More alterations were observed in liver after exposure to Acer 35 EC. In both sexes, IBR values were higher after 56 days than after 28 days of exposure. In conclusion, based on a large set of biomarkers and IBR values, the chronic exposure to low doses of insecticide Acer 35 EC seems to impair different physiological functions in Nile tilapia juveniles on a time-dependent manner, with a stronger impact on females than on males.

Weaning practices in phenylketonuria vary between health professionals in Europe

Background

In phenylketonuria (PKU), weaning is considered more challenging when compared to feeding healthy infants. The primary aim of weaning is to gradually replace natural protein from breast milk or standard infant formula with solids containing equivalent phenylalanine (Phe). In addition, a Phe-free second stage L-amino acid supplement is usually recommended from around 6 months to replace Phe-free infant formula. Our aim was to assess different weaning approaches used by health professionals across Europe.

Methods

A cross sectional questionnaire (survey monkey®) composed of 31 multiple and single choice questions was sent to European colleagues caring for inherited metabolic disorders (IMD). Centres were grouped into geographical regions for analysis.

Results

Weaning started at 17–26 weeks in 85% (n = 81/95) of centres, >26 weeks in 12% (n = 11/95) and < 17 weeks in 3% (n = 3/95). Infant's showing an interest in solid foods, and their age, were important determinant factors influencing weaning commencement. 51% (n = 48/95) of centres introduced Phe containing foods at 17–26 weeks and 48% (n = 46/95) at >26 weeks. First solids were mainly low Phe vegetables (59%, n = 56/95) and fruit (34%, n = 32/95).

A Phe exchange system to allocate dietary Phe was used by 52% (n = 49/95) of centres predominantly from Northern and Southern Europe and 48% (n = 46/95) calculated most Phe containing food sources (all centres in Eastern Europe and the majority from Germany and Austria). Some centres used a combination of both methods.

A second stage Phe-free L-amino acid supplement containing a higher protein equivalent was introduced by 41% (n = 39/95) of centres at infant age 26–36 weeks (mainly from Germany, Austria, Northern and Eastern Europe) and 37% (n = 35/95) at infant age > 1y mainly from Southern Europe. 53% (n = 50/95) of centres recommended a second stage Phe-free L-amino acid supplement in a spoonable or semi-solid form.

Conclusions

Weaning strategies vary throughout European PKU centres. There is evidence to suggest that different infant weaning strategies may influence longer term adherence to the PKU diet or acceptance of Phe-free L-amino acid supplements; rendering prospective long-term studies important. It is essential to identify an effective weaning strategy that reduces caregiver burden but is associated with acceptable dietary adherence and optimal infant feeding development.

Early feeding practices in infants with phenylketonuria across Europe

Background

In infants with phenylketonuria (PKU), dietary management is based on lowering and titrating phenylalanine (Phe) intake from breast milk or standard infant formula in combination with a Phe-free infant formula in order to maintain blood Phe levels within target range. Professionals use different methods to feed infants with PKU and our survey aimed to document practices across Europe.

Methods

We sent a cross sectional, survey monkey® questionnaire to European health professionals working in IMD. It contained 31 open and multiple-choice questions. The results were analysed according to different geographical regions.

Results

Ninety-five centres from 21 countries responded. Over 60% of centres commenced diet in infants by age 10 days, with 58% of centres implementing newborn screening by day 3 post birth. At diagnosis, infant hospital admission occurred in 61% of metabolic centres, mainly in Eastern, Western and Southern Europe. Breastfeeding fell sharply following diagnosis with only 30% of women still breast feeding at 6 months.

53% of centres gave pre-measured Phe-free infant formula before each breast feed and 23% alternated breast feeds with Phe-free infant formula. With standard infant formula feeds, measured amounts were followed by Phe-free infant formula to satiety in 37% of centres (n = 35/95), whereas 44% (n = 42/95) advised mixing both formulas together. Weaning commenced between 17 and 26 weeks in 85% centres, ≥26 weeks in 12% and < 17 weeks in 3%.

Discussion

This is the largest European survey completed on PKU infant feeding practices. It is evident that practices varied widely across Europe, and the practicalities of infant feeding in PKU received little focus in the PKU European Guidelines (2017). There are few reports comparing different feeding techniques with blood Phe control, Phe fluctuations and growth. Controlled prospective studies are necessary to assess how different infant feeding practices may influence longer term feeding development.

Fish larval recruitment to reefs is a thyroid hormone-mediated metamorphosis sensitive to the pesticide chlorpyrifos

Larval recruitment, the transition of pelagic larvae into reef-associated juveniles, is a critical step for the resilience of marine fish populations but its molecular control is unknown. Here, we investigate whether thyroid-hormones (TH) and their receptors (TR) coordinate the larval recruitment of the coral-reef-fish Acanthurus triostegus. We demonstrate an increase of TH-levels and TR-expressions in pelagic-larvae, followed by a decrease in recruiting juveniles. We generalize these observations in four other coral reef-fish species. Treatments with TH or TR-antagonist, as well as relocation to the open-ocean, disturb A. triostegus larvae transformation and grazing activity. Likewise, chlorpyrifos, a pesticide often encountered in coral-reefs, impairs A. triostegus TH-levels, transformation, and grazing activity, hence diminishing this herbivore’s ability to control the spread of reef-algae. Larval recruitment therefore corresponds to a TH-controlled metamorphosis, sensitive to endocrine disruption. This provides a framework to understand how larval recruitment, critical to reef-ecosystems maintenance, is altered by anthropogenic stressors.

Many animals go through a larval phase before developing into an adult. This transformation is called metamorphosis, and it is regulated by hormones of the thyroid gland in vertebrates. For example, most fish found on coral reefs actually spend the first part of their life as free-swimming larvae out in the ocean. The larvae usually look very different from the juveniles and adults. When these fish become juveniles, the larvae undergo a range of physical and behavioral changes to prepare for their life on the reef. Yet, until now it was not known what hormones control metamorphosis in these fish.

To address this question, Holzer, Besson et al. studied the convict surgeonfish Acanthurus triostegus. This herbivorous coral-reef fish lives in the Indo-Pacific Ocean, and the results showed that thyroid hormones do indeed regulate the metamorphosis of its larvae. This includes changing how the larvae behave and how their adult features develop. Further, Holzer, Besson et al. found that this was also true for four other coral-reef fish, including the lagoon triggerfish and the raccoon butterflyfish. In A. triostegus, thyroid hormones controlled the changes that enabled the juveniles to efficiently graze on algae growing on the reef such as an elongated gut.

When the fish larvae were then exposed to a pesticide called chlorpyrifos, a well-known reef pollutant, their hormone production was disturbed. This in turn affected their grazing behavior and also their metamorphosis. These fish had shortened, underdeveloped guts and could not graze on algae as effectively.

Herbivorous fish such as A. triostegus play a major role in supporting coral reef ecosystems by reducing algal cover and therefore promoting coral recruitment. These new findings show that pollutants from human activities could disturb the metamorphosis of coral-reef fish and, as a consequence, their ability to maintain the reefs. A next step will be to test what other factors can disrupt the hormones in coral-reef fish and thus pose a threat for fish populations and the coral-reef ecosystem.

[Pacemaker implantation in dogs: results of the last 30 years]

Pacemaker implantation in veterinary practice is still not well known and remains uncommon. However, this technique is the only possible way to cure animals suffering from symptomatic bradycardia whose state does not improve with a medical treatment. In most cases, the use of pacemakers in veterinary medicine leads to the disappearance of the clinical and electrocardiographic signs. This retrospective study concerning the last 30 years draws up an evaluation of the improvements, advantages and drawbacks of this method. Moreover, this study allows the understanding of the evolution of pacemakers' use in veterinary cardiology.

Efficacy of Humalog injections before an afternoon meal and their acceptance by children and adolescents with type 1 diabetes

AIMS

To evaluate the acceptability and efficacy of an injection of insulin lispro, before an afternoon meal.

METHODS

The subjects, 43 patients with Type 1 diabetes, 16 boys and 27 girls, aged 12.4 +/- 2.4 years, were randomly assigned to the treatment (n = 20) or the untreated control group (n = 23). The treatment was an injection of insulin lispro immediately before the afternoon meal. The control group had no injection. The treatment and the control group consumed identical types of meals for 2 months. The mean before-dinner blood glucose was measured during the last 2 weeks of the study.

RESULTS

Injection of insulin lispro resulted in a significant reduction in the before-dinner blood glucose compared with the untreated control group (10.4 +/- 3.8 mmol/l vs. 14.7 +/- 3.9 mmol/l, respectively). The number of days on which the blood glucose was > 10 mmol/l was reduced by half in the insulin lispro group. The difference in HbA1c between baseline and endpoint differed slightly but significantly between the two groups, in boys. Treated patients ate the meal less frequently (11.4 +/- 3.0 times per 15 days) than the control patients (14.4 +/- 0.6 times per 15 days) and injected themselves with insulin 8.9 +/- 3.6 times per 15 days. The HbA1c increased significantly with the number of meals taken without injection. There was no statistically significant difference in the frequency of hypoglycaemia or changes in weight between the two groups.

CONCLUSIONS

We conclude that an injection of insulin lispro before the afternoon meal can effectively lower the before-dinner blood glucose, and in boys also lowers the HbA1c. Patients were satisfied with the lower blood glucose before dinner, and did not find the insulin lispro injection difficult. However, compliance with the protocol procedures decreased during a subsequent 6-month period.

[Evaluation of dietary vitamin A intake in children with and without growth retardation]

BACKGROUND

A possible involvement of vitamin A in regulating physiological nocturnal growth hormone secretion has been recently suggested leading us to evaluate the daily vitamin A supply in prepubertal school children.

POPULATION AND METHODS

A questionnaire including a list of foods containing vitamin A and/or beta-carotene was answered with the aid of the parents. Vitamin A supply was expressed in retinol-Equivalent and estimated as mean daily intake over a one-year period. Following this methodology, a study was conducted in 104 control school children with normal stature and 110 children with short stature.

RESULTS

The total daily vitamin A intake (mean +/- SD: 1.197 micrograms +/- 799), retinol (675 micrograms +/- 628) and beta carotene (525 micrograms +/- 355) was above or equal to the recommended intake in more than 75% of the control children. In contrast, the total daily vitamin A intake (mean +/- SD: 787 micrograms +/- 850, P < 0.0002) retinol (436 micrograms +/- 670, P < 0.0004) and beta carotene (353 micrograms +/- 466, P < 0.002) was significantly decreased in those children with short stature, more than 35% of them having daily intake below the recommended one. The dietary vitamin A intake was also deficient when expressed as ER/1,000 calories (mean SD = 444 +/- 262) in the 46 children with short stature in whom the calorie intake had been evaluated for three days.

CONCLUSIONS

This study confirms that annual dietary vitamin A intake can easily be measured in school children. Its results suggest that this intake, relatively deficient in children with short stature, could be correlated with deficient secretion of growth-hormone.

Vitamin A deficiency and nocturnal growth hormone secretion in short children

In the growth hormone (GH) neurosecretory dysfunction syndrome affecting slowly growing children with delayed bone age, low nocturnal GH secretion is accompanied by normal responses to pharmacological stimuli. We compared plasma vitamin A with physiological nocturnal and stimulated GH secretion in 68 short prepubertal children. Fasting plasma vitamin A correlated with nocturnal GH secretion but not with stimulated GH secretion. Total dietary vitamin A intake was significantly lower in short children with abnormal nocturnal GH secretion than in normal children and in endocrinologically-normal short children. 9 of 12 children with low nocturnal GH secretion and normal stimulated GH peaks who were supplemented with vitamin A 3000 micrograms for 3 months had increased nocturnal GH secretion.