Sensory perception of textural properties of cosmetic Pickering emulsions.

OBJECTIVE: The increasing interest for the Pickering emulsions is based on the possibility to replace classical emulsifiers by the solid particles. This approach is extremely attractive for the cosmetic field. But, the main difficulty is to obtain stable emulsions with appreciable skin feel. However, there is no information about the texture of such systems. The aim of this study is to formulate and describe the textural properties of cosmetic Pickering emulsions compared with conventional systems. METHODS: Three metal oxides were selected: titanium dioxide, zinc oxide and silicon dioxide, able to form stable and totally emulsified systems. A conventional emulsifier was used to formulate the emulsion of reference. Finally, the mixture of two emulsifying systems, combining both, surfactant and particles, was also studied. Then, a sensory panel was asked to quantify the intensities of the perception of the seven discriminating attributes. RESULTS: Each particle brought its properties to the textural perception of the emulsion. TiO2 particles ensured the whitening effect of the emulsions, SiO2 provided the screech residue, whereas ZnO gave intermediate results. The conventional surfactant was perceived as glossy, greasy and more difficult to spread. The particle/surfactant mixtures gave mostly in-between results. CONCLUSIONS: The study shows that the sensory profile of Pickering emulsions is indirectly and directly governed by the particle properties used for the emulsion stabilization: indirectly, through affecting the emulsion orientation (oil in water or water in oil), the droplet organization and viscosity, and directly, through the particle perception on the skin surface.

OBJECTIF: L'intérêt croissant pour les émulsions de type Pickering repose sur la possibilité de remplacer les émulsifiants classiques par les particules solides. Cette approche est extrêmement attractive pour le domaine cosmétique. Mais, la principale difficulté est d'obtenir des émulsions stables avec un toucher agréable. Cependant, il n'y a aucune information sur la texture de tels systèmes. Le but de cette étude est de formuler et de décrire les propriétés de texture des émulsions cosmétiques de type Pickering par rapport aux systèmes conventionnels. MÉTHODES: Trois oxydes métalliques ont été sélectionnés: le dioxyde de titane, l'oxyde de zinc et le dioxyde de silicium, capables de former des systèmes stables et totalement émulsifiés. Un émulsifiant conventionnel a été utilisé pour formuler l'émulsion référence. Enfin, le mélange de deux systèmes émulsionnants, combinant à la fois le tensioactif et les particules, a également été étudié. Ensuite, un panel sensoriel a quantifié les intensités de perception des sept attributs discriminants. RÉSULTATS: Chaque particule a apporté ses propriétés à la perception de la texture de l'émulsion. Les particules de TiO2 ont assuré l'effet blanchissant des émulsions, SiO2 a rendu le résidu crissant, tandis que ZnO a donné des résultats intermédiaires. Le surfactant conventionnel était perçu comme brillant, gras et plus difficile à étaler. Les mélanges particules/tensioactifs ont donné principalement des résultats intermédiaires. CONCLUSION: L'étude montre que le profil sensoriel des émulsions Pickering est indirectement et directement gouverné par les propriétés des particules utilisées pour la stabilisation de l'émulsion: indirectement, en contrôlant l'orientation de l'émulsion (huile dans l'eau ou eau dans l'huile), l'organisation des gouttelettes et la viscosité, et directement, grâce à la perception des particules à la surface de la peau.

Cadmium-Induced Renal Cell Toxicity Is Associated With MicroRNA Deregulation.

Cadmium is an environmental pollutant well known for its nephrotoxic effects. Nevertheless, mechanisms underlying nephrotoxicity continue to be elucidated. MicroRNAs (miRNAs) have emerged in recent years as modulators of xenobiotic-induced toxicity. In this context, our study aimed at elucidating whether miRNAs are involved in renal proximal tubular toxicity induced by cadmium exposure. We showed that cadmium exposure, in 2 distinct renal proximal tubular cell models (renal proximal tubular epithelial cell [RPTEC]/human telomerase reverse transcriptase [hTERT] and human kidney-2), resulted in cytotoxicity associated with morphological changes, overexpression of renal injury markers, and induction of apoptosis and inflammation processes. Cadmium exposure also resulted in miRNA modulation, including the significant upregulation of 38 miRNAs in RPTEC/hTERT cells. Most of these miRNAs are known to target genes whose coding proteins are involved in oxidative stress, inflammation, and apoptosis, leading to tissue remodeling. In conclusion, this study provides a list of dysregulated miRNAs which may play a role in the pathophysiology of cadmium-induced kidney damages and highlights promising cadmium molecular biomarkers that warrants to be further evaluated.

Local pesticide use intensity conditions landscape effects on biological pest control.

Complex landscapes including semi-natural habitats are expected to favour natural enemies thereby enhancing natural pest biocontrol in crops. However, when considering a large number of situations, the response of natural biocontrol to landscape properties is globally inconsistent, a possible explanation being that local agricultural practices counteract landscape effects. In this study, along a crossed gradient of pesticide use intensity and landscape simplification, we analysed the interactive effects of landscape characteristics and local pesticide use intensity on natural biocontrol. During 3 years, using a set of sentinel prey (weed seeds, aphids and Lepidoptera eggs), biocontrol was estimated in 80 commercial fields located in four contrasted regions in France. For all types of prey excepted weed seeds, the predation rate was influenced by interactions between landscape characteristics and local pesticide use intensity. Proportion of meadow and length of interface between woods and crops had a positive effect on biocontrol of aphids where local pesticide use intensity was low but had a negative effect elsewhere. Moreover, the landscape proportion of suitable habitats for crop pests decreased the predation of sentinel prey, irrespectively of the local pesticide use intensity for weed seeds, but only in fields with low pesticide use for Lepidoptera eggs. These results show that high local pesticide use can counteract the positive expected effects of semi-natural habitats, but also that the necessary pesticide use reduction should be associated with semi-natural habitat enhancement to guarantee an effective natural biocontrol.

Influence of the emollient on emulsions containing lamellar liquid crystals: from molecular organization towards applicative properties.

OBJECTIVE: The sensory perception of cosmetic emulsions is complex as it is governed by an important number of parameters like the choice of raw materials, their interactions, the structural organisation of the system, etc. The aim of the present work was to go further in the interpretation of the emollient-surfactant interactions, towards the emulsions applicative properties. For this purpose, two systems containing liquid crystals of the lamellar type were formulated, differing only in the selected emollient. METHODS: First, the liquid crystals types were checked using different tools like the optical microscopy under the bright and polarized light, the wide-angle X rays diffraction and, finally, thermogravimetric analysis. Next, two sensory attributes, namely compression force and difficulty of spreading, were evaluated by a sensory panel. In addition to that, complementary instrumental characterizations (flow tests, textural analysis and contact angle measurements) were performed in order to understand how the panel could discriminate the products. RESULTS: The results showed that isohexadecane emollient induces the α-gel structures, while caprylic capric triglycerides favour the formation of the lamellar liquid crystals near to α-gel. For the compression force, the results point out that there is no direct interaction between the oil phase and the skin. For this attribute, depending on its chemical structure, emollient impacts the human perception only by changing the lamellar phase type. Concerning the difficulty of spreading, both the emulsion structure and the emollient properties should be considered. Immediate perception is impacted by the emulsions destruction, making the droplet roll one on each other. Then, once the droplets monolayer is disrupted, the emollient comes into direct contact with the skin. In this case, the perception is governed by the direct affinity of the emollient with the skin, nonpolar emollients being easier to spread if compared to polar ones. CONCLUSION: The sensory perception is guided not only by the choice of the raw materials but also by their interactions. It was shown that the chemical structure of the emollients affected the molecular organization of liquid crystals present in the emulsion and, consequently, directly or indirectly its sensory perception.

Structural and functional development of small intestine in intrauterine growth retarded porcine offspring born to gilts fed diets with differing protein ratios throughout pregnancy.

Protein level in the maternal diet plays a crucial role in fetal programming during pregnancy. Low or high protein level increases the risk of intrauterine growth retardation (IUGR). The aim of this study was to investigate the structural and functional development of the small intestine in piglets from sows fed a control (C, 12.1% protein), a high protein (HP, 30% protein), or a low protein (LP, 6.5% protein) diet during pregnancy. Newborns were classified as IUGR (birth weight ≤1.18 kg) and non-IUGR (birth weight >1.18 kg). The piglets were euthanized on postnatal day (PD)1, PD28 and PD188. The LP diet in non-IUGR neonates resulted in decreased body weight on PD1. The LP and HP diets resulted in both decreased body weight and delayed catch-up growth in the IUGR piglets. The HP and LP-diets increased the length of villi on PD1 in non-IUGRs but not in IUGRs. At birth, the expressions of Ki67 and active caspase 3 in mid-jejunum epithelium of HP and LP non-IUGR neonates were significantly lower as compared to C non-IUGRs whilst in IUGRs the respective expressions were as high as in C non-IUGRs. The postnatal dynamics of brush border enzyme activities and vacuolated enterocytes disappearance showed significant drop in enterocyte maturation in IUGR as compared to non-IUGR neonates. In conclusion, both HP and LP diets led to retarded development of non-IUGR piglets. In IUGR piglets both HP and LP diets resulted in delayed catch-up growth, without adaptive changes in brush border digestive enzymes.

Pancreatic enzyme deficiency depends on dietary protein origin in milk-fed calves.

In young mammals, milk proteins and their substitutes are used in milk formula. Protein substitution modifies diet digestibility and pancreatic secretions. The aim of this study was to test if milk protein substitution could generate pancreatic deficiency in milk-fed calves. The effect of pancreatic juice on the digestibility of proteins was studied. Measurement of apparent fecal nutrient digestibility was used to estimate digestion. Ten calves (60 to 130 d old) were chronically fitted with pancreatic accessory duct cannulas and 2 duodenal cannulas to provide precise measurement, sampling, and reintroduction of pancreatic juice as well as additional infusions. Animals were fed milk formula based on skim milk powder or soybean concentrate. Level of deficiency depended on dietary protein origin. Twice as much protein or trypsin was required with a soybean concentrate diet than with a skim milk powder diet to obtain maximal nutrient digestibility. Pancreatic protein concentration in the juice can be used to differentiate between normal and deficient animals. Among these proteins, trypsin measurement is a good pancreatic deficiency marker. These results confirmed the major role of exocrine pancreatic secretions in producing optimal digestion in young calves. Furthermore, practical applications of these results can be applied for the young in other animal species and in humans.

Dietary sodium butyrate supplementation increases digestibility and pancreatic secretion in young milk-fed calves.

The aim of this study was to test, in 8 calves fed milk formula based on soybean protein, the ability of sodium butyrate (SB) supplementation to improve nutrient digestibility and daily pancreatic secretions and to modify the kinetics of these secretions. Additionally, effects of duodenal SB infusion were evaluated. Plasma levels of gastrin, secretin, and cholecystokinin were measured. Butyrate supplementation in milk formula increased nutrient digestibility and total daily pancreatic secretions. For juice volume, this increase was most important from 12 to 17h after the morning meal. During the 3-h postprandial period, oral SB supplementation reduced the physiological decrease of postprandial pancreatic secretion (while duodenal digesta flow rate was maximal) and had a minor effect on plasma gut regulatory peptide concentrations. Compared with the diet without SB, ingestion of SB stimulated pancreatic secretion. Taken together, these results could explain the measured increase in nutrient digestibility. The data obtained after duodenal SB infusion did not indicate an effect on pancreatic secretion, apart from elevated lipase output compared with control. The mechanisms responsible for these events are not known and circulating gut regulatory peptides do not seem to be implicated. Our work brings new results regarding SB as a feed additive in young calf nutrition.

Effects of level of feed intake on pancreatic exocrine secretions during the early postweaning period in piglets.

The objective of this study was to determine the influence of the level of feed intake and a 2-d feed restriction period on the postweaning adaptation of pancreatic exocrine secretions. At 33 d of age, 18 piglets fitted with 2 permanent catheters (for pancreatic juice collection and reintroduction) were weaned and allocated to 1 of the following 2 dietary treatments for 5 d: restricted feed allocation (restricted) or gradually increasing feed allocation (control). Pancreatic juice was collected daily during both basal and prandial periods. The basal period was defined as the period from 1400 to 1700 h (i.e., 5 to 8 h after the morning meal), whereas the prandial period was defined as the period from 30 min before to 60 min after the morning meal (given at 0900). Digestive enzyme activities and antibacterial activity were determined. Pancreatic protein secretion was 44% less (P < 0.05) in restricted piglets than in control piglets during the basal period. Trypsin secretion was affected by feed-restriction of piglets. The meal did not affect protein and trypsin secretions in restricted piglets, whereas at d 3 postweaning, protein and trypsin secretions and trypsin specific activity in control piglets were 9-, 105-, and 25-fold greater (P < 0.001) during the first 30 min after the meal than before the meal. Lipase and amylase secretions were not affected by variations in feed intake. The secretion of antibacterial activity in restricted piglets was greater (P < 0.05) than that of control piglets only at d 5. The extended feed restriction period increased the basal secretion of antibacterial activity (P = 0.09) and postprandial secretion of amylase (P = 0.05). In conclusion, a low level of feed intake during the early postweaning period decreased pancreatic protein and trypsin secretions, whereas a 2-d feed restriction period enhanced secretions of amylase and antibacterial activity. In addition, our results indicate that during periods of dietary adaptation, such as at weaning, measurements of enzyme activities in the tissue do not accurately reflect the enzyme secretion.

INTACS inserts for treating keratoconus: one-year results.

OBJECTIVE: To evaluate the use of INTACS micro-thin prescription inserts (Kera Vision, Inc., Fremont, CA) for the treatment of keratoconus. DESIGN: Prospective, nonrandomized (self-controlled) comparative trial. PARTICIPANTS/INTERVENTION: Ten patients from our prospective clinical study who had completed 12 months of follow-up were evaluated. All patients had keratoconus with clear central corneas and were contact lens intolerant. After reviewing corneal pachymetry and topography of individual patients, INTACS inserts of 0.45-mm thickness were placed in the inferior cornea to lift the cone and INTACS of 0.25-mm thickness were inserted superiorly to counterbalance and flatten the overall anterior corneal surface. MAIN OUTCOME MEASURES: Differences between preoperative and postoperative uncorrected visual acuity, best spectacle-corrected visual acuity, manifest refraction, and keratometry values were statistically assessed. Changes in corneal ectasia were evaluated by reviewing corneotopographic maps. RESULTS: No intraoperative complications occurred in this series of patients. Spherical equivalent error and refractive astigmatism were reduced with INTACS inserts treatment. Postoperative month 12 uncorrected visual acuity (logarithm of the minimum angle of resolution [logMAR] mean, 0.35, standard deviation [SD], 0.16 [approximately 20/50, approximately 2 lines]) was significantly better than preoperative (logMAR mean, 1.05; SD, 0.33 [approximately 20/200, approximately 3 lines]; P

Correcting keratoconus with intracorneal rings.

PURPOSE: To evaluate the potential of intrastromal corneal ring technology (Intacs, KeraVision) to correct keratoconus without central corneal scarring. SETTING: Department of Ophthalmology, Brest University Hospital, Brest, France. METHODS: In this prospective, noncomparative, interventional case series, Intacs segments were implanted in 10 keratoconic eyes with clear central corneas and contact lens intolerance after corneal pachymetry was checked. Segment thicknesses varied based on corneal topography analysis. RESULTS: No intraoperative complications occurred. The mean follow-up was 10.6 months. Postoperative results revealed a reduction in astigmatism and spherical correction and an increase in topographical regularity and increased uncorrected visual acuity. CONCLUSION: Intacs technology can reduce the corneal steepening and astigmatism associated with keratoconus.

[Excimer photorefractive keratectomy (PRK) versus intrastromal corneal ring segments (ICRS) for correction of low myopia]. / Photoablation réfractive excimer (prk) versus Intacs (ICRS) pour la correction des myopies faibles.

PURPOSE: Theoretical differences between ablative and additive surgeries are obvious, but what about final outcome? We decide to compare surface excimer photorefractive ablation (PRK) with Intracorneal segments (Intacs or ICRS) for correction of low myopia. MATERIAL: and METHOD: Two homogeneous groups of 25 low pure myopic patients were considered: group A including patients operated with Excimer and group B corresponding to Intacs implanted eyes. Retrospective analysis was performed and compared data achieved at two years follow-up, in term of refractive results and qualitative vision. RESULTS: Considering non corrected visual acuity, percentages of eyes who achieved 20/40 or better are comparable in the two series (respectively 97% in group A and 99% in group B). In the adverse, proportion of patients achieving 20/20 or more is superior in Intacs group (77%) versus 62% in PRK group. In all cases, quality of vision is altered in early postoperative period, then returns to normal between 1 and 3 months. Functional complaints appear more frequent and persisting in intrastromal segments group. Based on videotopography and cycloplegic refraction, it seems that risk of induced astigmatism occurrence is significantly increased in case of Intacs. No severe complication is mentioned in both groups. CONCLUSION: Final outcome are in favor of the efficacy, safety and predictability of the two methods for correction of low myopia. Concept of Intacs presents the interest of potential adjustability and respect of central corneal area; however it appears to be limited by the occurrence of an induced astigmatism.

Hyperadrenergic syndrome in severe tetanus: extreme rise in catecholamines responsive to labetalol.

The hyperadrenergic syndrome that occurs in tetanus is characterised by hypertension, tachycardia, and increased systemic arteriolar resistance. A 74 year old man with tetanus was found to have very high catecholamine concentrations--as high as those in phaeochromocytoma--and the fluctuations in blood pressure and heart rate were measured to see whether they paralleled changes in the catecholamine values. A labetalol infusion of 0.25-1 mg/min gradually stabilised the cardiovascular disturbances and the patient recovered.