Effect of alkalinization and ultra-high-pressure homogenization on casein micelles in raw and pasteurized skim milk.

Mechanical and physicochemical treatments of milk induce structural modifications of the casein (CN) micelles, affecting their techno-functional properties in dairy processing. Here, we studied the effect of alkalinization and ultra-high-pressure homogenization (UHPH) on CN micelles in raw skim milk (rSM) and pasteurized skim milk (pSM). The pH of both skim milks (approximately 6.7) was adjusted to 8.5 and 10.5 before UHPH at 100, 200, and 300 MPa. The structural changes of the CN micelles during the treatments were assessed using laser diffraction, transmission electron microscopy, and turbidity measurements. Finally, ultracentrifugation (70,000 × g for 1 h at 20°C) was carried out to evaluate the protein's distribution between the supernatant (serum phase) and the pellet (colloidal phase) by gel electrophoresis and protein concentration measurement. Alkalinization of both skim milks induced a significant reduction in turbidity, whereas an increase of the average particle size was observed, the effect being more severe in pSM than rSM. At alkaline pH, more proteins were recovered in the serum phase, which suggested that the CN underwent major rearrangements into nonsedimentable CN forms of various sizes, as confirmed by transmission electron microscopy. The amount of CN found in the serum phase at pH 8.5 also increased with the UHPH pressure. Although UHPH did not influence the average CN micelle size at pH 6.7 and 8.5, a pressure-dependent decrease was observed at pH 10.5 for both skim milks. The structural changes of the CN micelles observed in this study throughout the combination of alkalinization and UHPH could be of interest for developing new dairy ingredients with improved functionality.

Behçet's disease uveitis.

Uveitis in Behçet's disease (BD) is frequent (40% of cases) and is a major cause of morbidity. The age of onset of uveitis is between 20 and 30 years. Ocular involvement includes anterior, posterior or panuveitis. It is non-granulomatous. Uveitis may be the first sign of the disease in 20% of cases or it may appear 2 or 3 years after the first symptoms. Panuveitis is the most common presentation and is more commonly found in men. Bilateralisation usually occurs on average 2 years after the first symptoms. The estimated risk of blindness at 5 years is 10-15%. BD uveitis has several ophthalmological features that distinguish it from other uveitis. The main goals in the management of patients are the rapid resolution of intraocular inflammation, prevention of recurrent attacks, achievement of complete remission, and preservation of vision. Biologic therapies have changed the management of intraocular inflammation. The aim of this review is to provide an update previous article by our team on pathogenesis, diagnostic approaches, identification of factors associated with relapse and the therapeutic strategy of BD uveitis.

Are intravitreal injections essential during the COVID-19 pandemic? Global preferred practice patterns and practical recommendations.

Tertiary outpatient ophthalmology clinics are high-risk environments for COVID-19 transmission, especially retina clinics, where regular follow-up is needed for elderly patients with multiple comorbidities. Intravitreal injection therapy (IVT) for chronic macular diseases, is one of the most common procedures performed, associated with a significant burden of care because of the vigorous treatment regimen associated with multiple investigations. While minimizing the risk of COVID-19 infection transmission is a priority, this must be balanced against the continued provision of sight-saving ophthalmic care to patients at risk of permanent vision loss. This review aims to give evidence-based guidelines on managing IVT during the COVID-19 pandemic in common macular diseases such as age-related macular degeneration, diabetic macula edema and retinal vascular disease and to report on how the COVID-19 pandemic has affected IVT practices worldwide.To illustrate some real-world examples, 18 participants in the International Retina Collaborative, from 15 countries and across four continents, were surveyed regarding pre- and during- COVID-19 pandemic IVT practices in tertiary ophthalmic centers. The majority of centers reported a reduction in the number of appointments to reduce the risk of the spread of COVID-19 with varying changes to their IVT regimen to treat various macula diseases. Due to the constantly evolving nature of the COVID-19 pandemic, and the uncertainty about the normal resumption of health services, we suggest that new solutions for eye healthcare provision, like telemedicine, may be adopted in the future when we consider new long-term adaptations required to cope with the COVID-19 pandemic.

[Treatment of noninfectious intermediate uveitis, posterior uveitis, or panuveitis]. / Traitement des uvéites intermédiaires, postérieures et panuvéites non infectieuses.

Controlling long-term inflammation during non-infectious intermediate, posterior or panuveitis while limiting side effects remains challenging. There is no standardized pre-therapeutic evaluation providing diagnostic certainty, but some simple tests allow us to identifiy the main etiologies. The ophthalmologist identifies the type of uveitis, and the internist completes the investigations according to the ophthalmologist's findings. Fundus photographs, optical coherence tomography, and fluorescein and indocyanine green angiography should be considered during diagnosis and follow-up. Ocular complications of uveitis are numerous. They require close monitoring and specific medical and sometimes surgical management. The growing number of available drugs makes it possible to optimize the management of these conditions with varied etiologies and presentations. Currently, systemic corticosteroids remain the mainstay of therapy, and other alternatives are considered in the case of poor tolerance, steroid resistance or dependence. The choice of a systemic, periocular or intravitreal treatment depends on several factors: chronicity or recurrence of uveitis, duration, bilaterality, association with a systemic inflammatory disease, the presence of contraindications to certain treatments, and also socioeconomic constraints. It is of the utmost importance to find the best compromise allowing tight control of ocular inflammation by means of adapted systemic and/or local treatment while avoiding the main complications.

[Birdshot retinochoroidopathy: Key messages]. / Rétinochoroïdopathie de type Birdshot : les éléments clés.

Birdshot retinochoroidopathy (BRC) is a potentially blinding posterior autoimmune uveitis that affects Caucasian patients in their fifties. Strongly associated with the HLA A 29 phenotype, BRC is characterized by the presence of suggestive choroidal lesions on the fundus, but their apparition can be delayed. Visual acuity is not a good descriptive factor of visual function. Ancillary tests can therefore help establish the diagnosis and allow proper follow-up of BRC patients: optical coherence tomography can reveal either oedema or atrophy of the macula. Fluorescein and infracyanine green angiograms can show signs of inflammatory activity and give further diagnostic clues. Electroretinograms and visual fields can be useful for the diagnosis and follow-up. BCR patients should be examined periodically and undergo exhaustive clinical and paraclinical tests to insure the best prognosis. Corticosteroids should be associated with immunosuppressive treatments as early as possible in the presence of factors that are predictive of the worse prognoses.