Retinyl Acetate Research Articles

The effects of preformed vitamin A and provitamin A carotenoid supplementation on tadpoles of the poison frog Phyllobates vittatus.

Understanding the nutritional requirements of captive animals is necessary for proper animal husbandry, however, the specific dietary requirements for many amphibian species commonly kept in captivity are unknown. Like most vertebrates, frogs cannot synthesize carotenoids and must therefore obtain these essential nutrients through diet. It is unclear if amphibians can cleave provitamin A carotenoids to form vitamin A metabolically within the body, so common practice is to supplement their captive diets with both preformed vitamin A and provitamin A carotenoids. We carried out a feeding experiment in tadpoles of Phyllobates vittatus, a commonly kept poison frog species, to test the effects of supplementing a fish flake diet with a provitamin A carotenoid (2.5 mg/g β-carotene) and vitamin A (0.033-0.066 µg/mL retinyl acetate), both individually and in combination. Contrary to our expectations, supplementation had either no effect or adverse effects on tadpole growth and survivorship. Tadpoles reared under supplemented diets with vitamin A showed higher mortality rates, coupled with symptoms of hypervitaminosis A. Survivors had a smaller body size and mass at metamorphosis. β-carotene supplementation alone had no detectable effect. The vitamin A and β-carotene levels in our supplemented diet have been shown to be harmless or benefit tadpoles of other species, yet our results indicate that adding these amounts to what is found in a generalist fish flake mix can have detrimental effects on P. vittatus tadpoles. More broadly, this study highlights the importance of creating husbandry guidelines based on the specific physiological needs of the species (or species groups) being kept in captivity, rather than general ones for all amphibians, as is often done.

The Effect of Retinol Acetate on Liver Fibrosis Depends on the Temporal Features of the Development of Pathology

The effect of vitamin A on the manifestations of liver fibrosis is controversial and establishing the causes of its multidirectional influence is an urgent problem. In the work, the functional characteristics of the liver with Cu-induced fibrosis were determined after the restoration of vitamin A to the control level at the F0/F1 stage. In animals with liver fibrosis, classical indicators of physiology, functional activity of the liver, histological, and hematological characteristics were determined; the content of calcium and ROS was determined in bone marrow cells. It was shown that in the liver with Cu-induced fibrosis, the restoration of vitamin A content to control values after per os injections of a retinol acetate solution at a dose of 0.10mg (300 IU)/100g of body weight in the early stages of this pathology development (Fо/F1) was accompanied by: a decrease in the number of immunocompetent cells in the bloodstream to control values; normalization of the amount of calcium ions and ROS in bone marrow cells; restoration to the control level of activity of alkaline phosphatase; an increase in the number of binuclear hepatocytes; and restoration of the dynamics of body weight growth in experimental animals, even against the background of the ongoing action of the hepatotoxic factor. We came to the conclusion that the multidirectional action of vitamin A, which occurs in liver fibrosis, depends not only on the concentration of vitamin A in the liverbut also on temporal characteristics of cellular and metabolic links involved in the adaptive response formation. It was suggested that knowledge of the initial temporal metabolic characteristics and the amount of vitamin A in the liver, taking into account the stages of fibrosis development, can be an effective way to restore the altered homeostatic parameters of the body.

High Levels of Vitamin A in Plant-Based Diets for Gilthead Seabream (Sparus aurata) Juveniles, Effects on Growth, Skeletal Anomalies, Bone Molecular Markers, and Histological Morphology.

Substitution of fish-based ingredients may alter the nutritional profile of the feeds, including the vitamin contents, ultimately leading to unbalanced vitamin supply. Vitamin A plays an essential role in epithelium preservation, cell differentiation, reproduction, and vision. It also intervenes in skeletogenesis through chondrocytes development. Therefore, low levels of vitamin A may cause poor growth and abnormal bone development among other symptoms. Besides, in gilthead seabream excess vitamin A altered bone structure and homeostasis, indicating that an upper level for vitamin A in feeds for this species must be defined. For this purpose, a practical plant-based diet (FM 10% and FO 6%) containing five increasing levels of vitamin A (24,000, 26,000, 27,000, 31,000, and 37,000 IU/kg) supplemented as retinyl acetate was formulated to identify the effects of high levels of vitamin A for gilthead seabream juveniles. The trial was conducted with 450 total fish distributed into 15 tanks, where each diet was tested in triplicates for 70 days. At the end of the trial, samples were taken for analyses of vitamin A-relevant markers. At the end of the trial the high levels of vitamin A supplementation did not cause a reduction in growth, whereas no significant effect was observed for the feed efficiency, specific growth rate, and feed convertion ratio. Although not significant, retinol content in liver showed a tendency to increase with the elevation of dietary vitamin A levels. Although minor, the highest level of vitamin A dietary content (37,000 IU/kg) caused a significant increase in caudal vertebrae partial fusion as well as caudal vertebrae malformations. Increasing dietary vitamin A was related to a reduction in the occurrence of microhemorrhages in the liver and a reduction in the presence of eosinophils associated to the pancreas. Overall, the results of the present study suggested that gilthead seabream juveniles fed a plant-based diet are able to tolerate very high levels of vitamin A supplementation when supplemented as retinyl acetate. Nevertheless, further supplementation should be avoided in order to reduce the prevalence of anomalies affecting the caudal vertebrae.

Effects of sources and routes of administration of vitamins A, D and copper on postnatal status of these micronutrients in piglets.

Twenty-six nulliparous sows were fed conventional gestation and lactation diets supplemented (N = 13) or not (N = 13) with extra daily supplements of 25-hydroxy-cholecalciferol (25-OH-D3; 4 ĸIU), β-carotene (24 ĸIU), and copper (Cu)-proteinate (45 mg) from day 90 of gestation to 21 d of lactation (L21). In each litter, 10 piglets were divided into 5 pairs received, at 2 (L2) and 8 d (L8) of age, one of the five combinations of micronutrient sources and routes of administration (N = 260 piglets total). These neonatal treatments (N = 26 pairs or 52 piglets each) consisted of oral vitamin D3, retinol acetate and CuSO4 (T1); oral 25-OH-D3, β-carotene, and Cu proteinate (T2); exposure to ultraviolet light (UVB), oral retinol palmitate and Cu gluconate (T3); intramuscular vitamin D3 and retinyl propionate and oral Cu acetate (T4); oral saline (CTRL). Oral or intramuscular provisions corresponded to 12 mg of Cu and 70 and 12 ĸIU of vitamins A and D, respectively. Blood samples were collected from all piglets at L2, L8, and L21 for determination of serum Cu, retinol, and 25-OH-D3. Body weight was measured at birth, L2, L8, and L21. Piglets were weaned at L21, and liver and blood samples were collected 2 d later to evaluate oxidative enzymes in blood and liver and hepatic ATP concentrations and expression of genes associated with antioxidant status. Sow treatments had marginal or no impacts on Cu, retinol, 25-OH-D3, or antioxidant status in piglet blood serum and liver. However, when supplements were given to piglets, hepatic Cu was 38% greater in for all treated piglets compared to CTRL (P < 0.01), hepatic retinol was 3 times higher in T1 than in CTRL (P < 0.01) and intermediate for other treatments whereas serum 25-OH-D3 was markedly increased with T2 and T3 at L8 and L21, respectively, compared to CTRL (Piglet treatment × Age interaction, P < 0.01). Concerning antioxidant activities, glutathione peroxidase, and superoxide dismutase were increased (P < 0.03) in plasma of T2 piglets whereas the highest values (P < 0.03) for indicators of oxidative damage to proteins were observed in T4 piglets. The study revealed that oral Cu proteinate from T2, oral retinol acetate from T1, oral 25-hydroxy-cholecalciferol from T2, and UVB light exposure from T3 were the most efficient ways of increasing the postnatal status of these micronutrients in suckling piglets and this may have some impacts on their peri-weaning antioxidant status.

Comparison of five retinoids for anti-photoaging therapy: Evaluation of anti-inflammatory and anti-oxidative activities invitro and therapeutic efficacy invivo.

Over the past decades, increasing evidences have demonstrated that five retinoids, including retinol (ROL), retinol acetate (RAc), retinol propionate (RP), retinol palmitate (RPalm), and hydroxypinacolone retinoate (HPR), can be potential therapeutic agents for skin photoaging. However, therapeutic efficacies and biosafety have never been compared to these compounds. This study aimed to determine the optimal retinoid type(s) for anti-photoaging therapy both invitro and invivo. Our data demonstrated that four retinoids (RPalm, RP, HPR and ROL) but not RAc were effective for anti-photoaging treatment at 5 μg/mL invitro, with action mechanisms associated with antioxidative, anti-inflammatory and anti-skin ECM degradation activities. Notably, both RPalm and RP appeared superior to HPR and ROL for those activities. Importantly, both RPalm and RP were shown to be optimal for anti-photoaging therapy when topically applied at 5 mg/kg in a UVB-induced mice model of photoaging, which is consistent with their high anti-photoaging activities invitro. Additionally, topical application of these five retinoids showed satisfactory biosafety without causing significant apoptosis in animal organs, although RP application led to a slight decline in animal body weights. Collectively, these data have laid a good foundation for the next development of the clinical application of these retinoids for skin healthcare.

Lipase B from Candida antarctica immobilized on amphiphilic Janus halloysite nanosheet and application in biphasic interface conversion

Lipase B from Candida antarctica (CALB) plays a prominent role as a biocatalyst in several industries, especially for biphasic conversion of functional lipids. Herein, an amphiphilic Janus halloysite nanosheet (JHNS) was fabricated and employed simultaneously as a solid surfactant for stabilizing Pickering emulsion and as a carrier for immobilizing CALB, with the aim to realize highly efficient biphasic bioconversion. The obtained JHNS could stabilize Pickering emulsion for at least 7 days. Immobilization of CALB on JHNS improved the substrate affinity, catalytic efficiency, thermal stability, and alkaline tolerance of the enzyme. Moreover, JHNS-based immobilized CALB was exploited as a biocatalytic platform for the conversion of retinyl acetate, with almost twice increase in conversion efficiency. Taken together, the JHNS-based immobilized CALB paves the way for the design of efficient biphasic conversion system for the production of added-value lipids.

Efficacy Evaluation of Combination Therapy in Patients with Generalized Periodontitis According to the Index Estimation of Periodontal Status: Experimental Randomized Single-Arm Study

Background. Treatment and prevention of inflammatory periodontal diseases represent a serious general medical and social problem, which remains relevant due to the significant prevalence of periodontitis among the population, as well as the associated loss of teeth and the negative impact of periodontal foci of infection on the body as a whole. Chronic generalized periodontitis is difficult to treat: it is only possible to achieve periods of remission. Therefore, it is of great theoretical and practical importance to develop further ways to improve methods for treating inflammatory-dystrophic damage of periodontal tissues in chronic generalized periodontitis.Objective. To perform an index estimation of treatment efficacy in patients with moderately severe chronic generalized periodontitis.Methods. An experimental randomized single-arm study was conducted examining 204 patients diagnosed with moderately severe chronic generalized periodontitis. Patient examination and data analysis were carried out at the Dentistry Department of the Stavropol State Medical University and the Department for General Practice Dentistry of the Kuban State Medical University in 2021–2022. The study included patients aged 35 to 65 years diagnosed with moderately severe chronic generalized periodontitis. Patients with somatic diseases in the decompensation stage were not eligible for the study. The patients were randomly divided into three groups (closed-envelope method). Group 1 was treated using conventional methods. As well as conventional therapy, Group 2 was prescribed vitamin D (Aquadetrim® at a dose of 5000 IU once per day while monitoring vitamin D blood level). The third group of patients was prescribed conventional therapy along with the developed pharmacotherapy, which included vitamin D (Aquadetrim® at a dose of 5000 IU once per day), vitamin A (3.44% oil solution of retinol acetate at a dose of 50 000 IU, 15 min after a morning meal), and 2-ethyl-6-methyl-3-hydroxypyridine (Mexidol® at a dose of 125 mg twice a day). In each patient, the treatment efficacy was analyzed in adjacent oral cavity segments (split-mouth design) according to clinical pocket depth, attachment loss, and bleeding on probing. Also, the authors used the X-ray index to assess the condition of osseous structures and the simplified oral hygiene index. The specified indices were estimated prior to treatment and at one and 12 months following treatment. The statistical analysis of study results was performed using Excel Microsoft Office 2016 (Microsoft, USA).Results. The obtained data indicate that the immediate clinical outcomes (after one month) of combination therapy in patients from all three groups were approximately the same. However, the efficacy of treatment measures in the long-term period (12 months) was different, as evidenced by the dynamics of index values. Only in Group 3 patients, the full implementation of pharmacotherapeutic measures as part of the combination therapy of periodontitis ensured a stable therapeutic effect throughout the entire period of observation.Conclusion. The data obtained 12 months following treatment indicate that the additional prescription of the developed pharmacotherapy contributed to prompt inflammation relief in periodontal tissues, providing a stable treatment outcome and long-term remission.

Fabrication of polycaprolactone electrospun fibres with retinyl acetate for antioxidant delivery in a ROS-mimicking environment.

Background: Increased cancer rates denote that one in two people will be diagnosed with cancer in their lifetime. Over 60% of cancer patients receive radiotherapy, either as a stand-alone treatment or in combination with other treatments such as chemotherapy and surgery. Whilst radiotherapy is effective in destroying cancer cells, it also causes subsequent damage to healthy cells and surrounding tissue due to alterations in the tumor microenvironment and an increase in reactive oxygen species (ROS). This can cause extensive damage that impairs tissue function, and the likelihood of tissue regeneration and restoration of function is significantly reduced as new healthy cells cannot survive in the damaged environment. In the treatment of head and neck cancers, radiotherapy can cause salivary gland dysfunction. This significantly impairs the patient's quality of life and there is currently no cure, only palliative treatment options. Tissue engineering approaches are used to mimic the microenvironment of the tissue and can mediate the damaged microenvironment via bioactive compounds, to support the delivery, survival, and proliferation of new, healthy cells into the damaged environment. Methods: In this study, retinyl acetate, a derivative of vitamin A, was successfully incorporated into electrospun polycaprolactone fibres. Results: SEM images and characterization analyses showed that all scaffolds produced had similar characteristics, including fiber morphology and scaffold wettability. The vitamin scaffolds were shown to exert an antioxidant effect through scavenging activity of both DPPH and hydroxyl radicals in vitro. Critically, the antioxidant scaffolds supported the growth of human submandibular gland cells and significantly upregulated the expression of GPx1, an antioxidant enzyme, when cultured under both normal conditions and under a simulated oxidative stress environment. Discussion: These results suggest that incorporation of retinyl acetate into electrospun fibres has may mediate the damaged microenvironment post cancer radiation therapy.

Hif1α/Dhrs3a Pathway Participates in Lipid Droplet Accumulation via Retinol and Ppar-γ in Fish Hepatocytes.

Excessive hepatic lipid accumulation is a common phenomenon in cultured fish; however, its underlying mechanisms are poorly understood. Lipid droplet (LD)-related proteins play vital roles in LD accumulation. Herein, using a zebrafish liver cell line (ZFL), we show that LD accumulation is accompanied by differential expression of seven LD-annotated genes, among which the expression of dehydrogenase/reductase (SDR family) member 3 a/b (dhrs3a/b) increased synchronously. RNAi-mediated knockdown of dhrs3a delayed LD accumulation and downregulated the mRNA expression of peroxisome proliferator-activated receptor gamma (pparg) in cells incubated with fatty acids. Notably, Dhrs3 catalyzed retinene to retinol, the content of which increased in LD-enriched cells. The addition of exogenous retinyl acetate maintained LD accumulation only in cells incubated in a lipid-rich medium. Correspondingly, exogenous retinyl acetate significantly increased pparg mRNA expression levels and altered the lipidome of the cells by increasing the phosphatidylcholine and triacylglycerol contents and decreasing the cardiolipin, phosphatidylinositol, and phosphatidylserine contents. Administration of LW6, an hypoxia-inducible factor 1α (HIF1α) inhibitor, reduced the size and number of LDs in ZFL cells and attenuated hif1αa, hif1αb, dhrs3a, and pparg mRNA expression levels. We propose that the Hif-1α/Dhrs3a pathway participates in LD accumulation in hepatocytes, which induces retinol formation and the Ppar-γ pathway.

Preformulation and synthesis of retinol acetate nanoemulsion for skin disorder

Preformulation and synthesis of retinol acetate nanoemulsion for skin disorder

Antioxidant effect on shear bond strength of orthodontic brackets after tooth bleaching: A scoping review of in vitro studies

Tooth bleaching was reported to decrease bond strength of orthodontic brackets. The antioxidant application was investigated to reverse the bleaching effect for immediate bracket bonding. This scoping review of in vitro studies is to assess systematically the effect of antioxidant application on shear bond strength (SBS) before orthodontic bracket bonding after tooth bleaching. This review was provided according to the Preferred reporting items for systematic reviews and meta-analyses extension for scoping reviews (PRISMA-ScR) guidelines. An electronic literature search was performed for full-text articles in English via Scopus, Web of Science, MEDLINE/PubMed, and Google Scholar databases from 2012 to May 9, 2023. A total of 549 records were retrieved from the electronic search, and 361 after discarding duplicates. According to eligibility criteria, 23 records were included in this study. Included studies revealed that antioxidants could increase the SBS of brackets after bleaching. However, there was controversiality whether SBS was just improved or restored to the unbleached level according to various factors, including the antioxidant type, concentration, application time, and form. Most studies reported that 10% sodium ascorbate (SA), ascorbic acid, green tea (GT), and tocopherol solutions restored SBS of metal brackets but not ceramic brackets. The result of 10% SA and GT gel was controversial. Lower concentrations than 10% was effective with pink bark, grape seed, quercetin flavonoid, and chamomile to restore SBS. The included studies revealed that retinol acetate, gooseberry, and dimethyl sulfoxide did not restore SBS.

Effective, convenient, and green sample preparation for the determination of retinol and retinol acetate in human serum using pipette tip microextraction

An efficient sample preparation based on pipette tip microextraction that can be used for the analysis of retinol in human serum has been developed. Altogether, nine commercial pipette tips were compared based on recovery, sample volume, use of organic solvent, handling difficulty, duration of the preparation process, price, and greenness of the method. Retinol acetate was used as the internal standard. The extraction efficiency for both compounds was evaluated to optimize and select the best pipette tip for sample preparation, which was the WAX-S XTR pipette tip containing an ion exchanger and salt. This tip combined solid phase extraction and salting-out assisted liquid‒liquid extraction. Satisfying recoveries of 100 and 80% for retinol and retinol acetate, respectively, and good repeatability were demonstrated. The action of this pipette tip was based on the clean-up workflow in which the interferences were retained on the sorbent. The presence of residual interferences in the extracted samples did not affect the HPLC separation of compounds of interest. The simplicity of the clean-up workflow reduced the time of the sample preparation compared to the bind-wash-elute counterpart workflow. The advantages of our technique are its environmental friendliness and cost effectiveness. The selected pipette tip with an excellent microextraction efficiency enables sample preparation in both clinical research and practice.

Designing of novel nanoemulsions of retinol using box Behnken design for psoriasis

Psoriasis is a chronic inflammatory disease, which is triggered by genetic and environmental factors, has been found to be associated with comorbidities like psoriatic arthritis, Crohn's disease etc. Retinol acetate is an effective, first line anti-psoriatic drug for Psoriasis but researchers have indicated toxicity in case of its overdose. Present study is an attempt to design Retinol Acetate Nanoemulsion RANE with optimum dosage, improved hydration and penetration, hence better absorption. Box Behnken model of Design Expert version 12 was used for the optimization process to prepare O/W Nanoemulsion. RANE was evaluated by pH, viscosity, conductivity, particle size analysis and responses like % drug content and % in-vitro drug release at different time intervals were experimentally recorded. Predicted value and experimental value of % drug content was found to be 83.84 ± 0.12 and 80.24 ± 1.14 respectively with relative error of 3.6 ± 1.02. While these values for in-vitro drug release at 90 min interval was 47.21 ± 0.21 % and 48.23 ± 2.90 respectively with relative error of 1.02 ± 2.69. It’s p-value was found to be 0.02, which is significant and f value was 0.27 which is non-significant, VIF value was 1.0–1.03 and Ri 2 range was found to be 0–0.03 which proves the model is fit for optimization. These findings for optimized formulation might suggest promising results in effective treatment of psoriasis on further investigation.

RADIOLOGICAL CHANGES OF THE RABBIT KNEE JOINT IN EXPERIMENTAL OSTEOARTHRITIS

In veterinary medicine, radiological examinations are considered to be the most common and affordable method of diagnosing diseases of the musculoskeletal system in animals [1]. In this regard, the studies described in this article were aimed at assessing the degree of degenerative changes during the modelling of knee osteoarthritis using an X-ray apparatus. The material of the study was the joints of experimental animals (rabbits) with formed osteoarthritis of the knee joint on days 14, 21 and 28 of the experiment. The rabbits were modelled for degenerative changes in the knee joint by intra-articular injection of a 4% solution of retinol acetate and kojic acid. On days 7, 14, 21, and 28 of the experiment, X-ray examination was performed. Radiological examinations were performed in two projections, namely, in the direct (ventro-dorsal) and lateral (medio-lateral) projections. The study was carried out on the basis of the training laboratory "Veterinary Radiology and Radiodiagnostics" of the Department of Therapy and Clinical Diagnostics of the Faculty of Veterinary Medicine of the National University of Life and Environmental Sciences of Ukraine using the radiological device VATEL-1. On the 14th day of experimental studies, no visible bone pathology was observed in animals, the height of the joint gap was preserved bilaterally. On the 21st day, in the area of the right knee joint (where the pathological process was formed), a moderate decrease in the height of the joint gap was noted during radiography with a predominance in the medial section. On the 28th day of the experiment, a uniform decrease in the height of the joint gap was observed in the right knee joint during radiography. These changes indicate progressive degenerative changes with cartilage loss in the knee joint of the experimental animals. Thus, on X-ray images on days 21 and 28 of the experiment, a decrease in the height of the articular gap in the knee joint was noted.

Anthocyanin and Lycopene Contents Do Not Affect β-Carotene Bioefficacy from Multicolored Carrots (Daucus carota L.) in Male Mongolian Gerbils

BackgroundAnthocyanins and carotenoids are phytochemicals that may benefit health through provitamin A carotenoid (PAC), antioxidant, and anti-inflammatory activities. These bioactives may mitigate chronic diseases. Consumption of multiple phytochemicals may impact bioactivity in synergistic or antagonistic manners. ObjectivesTwo studies in weanling male Mongolian gerbils assessed the relative bioefficacy of β-carotene equivalents (BCEs) to vitamin A (VA) with simultaneous consumption of the non-PAC lycopene or anthocyanins from multicolored carrots. MethodsAfter 3-wk VA depletion, 5–6 gerbils were killed as baseline groups. The remaining gerbils were divided into 4 carrot treatment groups; the positive control group received retinyl acetate and the negative control group was given vehicle soybean oil (n = 10/group; n = 60/study). In the lycopene study, gerbils consumed feed varying in lycopene sourced from red carrots. In the anthocyanin study, gerbils consumed feed varying in anthocyanin content sourced from purple-red carrots, and positive controls received lycopene. Treatment feeds had equalized BCEs: 5.59 ± 0.96 μg/g (lycopene study) and 7.02 ± 0.39 μg/g (anthocyanin study). Controls consumed feeds without pigments. Serum, liver, and lung samples were analyzed for retinol and carotenoid concentrations using HPLC. Data were analyzed by ANOVA and Tukey’s studentized range test. ResultsIn the lycopene study, liver VA did not differ between groups (0.11 ± 0.07 μmol/g) indicating no effect of varying lycopene content. In the anthocyanin study, liver VA concentrations in the medium-to-high (0.22 ± 0.14 μmol/g) and medium-to-low anthocyanin (0.25 ± 0.07 μmol/g) groups were higher than the negative control (0.11 ± 0.07 μmol/g) (P < 0.05). All treatment groups maintained baseline VA concentrations (0.23 ± 0.06 μmol/g). Combining studies, serum retinol had 12% sensitivity to predict VA deficiency, defined as 0.7 μmol/L. ConclusionsThese gerbil studies suggested that simultaneous consumption of carotenoids and anthocyanins does not impact relative BCE bioefficacy. Breeding carrots for enhanced pigments to improve dietary intake should continue.

628 Intralesional electrosurgery of eyelid xanthelasma: a case report

Xanthelasma is the most common type of xanthoma in the periorbital region with clinical diagnosis. About 50% of patients have hypercholesterolemia in laboratory tests - inferring clinical importance to this condition. We aim to report a case of a 55-year-old female patient presenting yellowish papules on the upper eyelids diagnosed as Xanthelasma. She had hypercholesterolemia and type II diabetes in use of rosuvastatin 10mg and metformin 1000mg. She complaint of significant aesthetic discomfort that affected her interpersonal activities. It was performed intralesional electrosurgery with good outcome. The procedure starts with asepsis and antisepsis followed by local anesthetic button with 2% lidocaine and adrenaline. Next the xanthelasma is punctured with the same anesthesia needle leaving a small portion exposed so that there is contact with the electrocautery. The radiofrequency is applied to the needle that works as an intralesional conductor of energy, always using the lowest frequency capable of generating whitening of the xanthelasma - which denotes denaturation of lipids. Finally, the needle is removed and the procedure is concluded with the patient being instructed to use ointment with retinol acetate 10,000 IU, amino acids 25mg, methionine 5mg and chloramphenicol 5mg in vehicle: methylparaben, propylparaben, cetyl alcohol, lanolin, solid petroleum jelly and microcrystalline wax (trade name Epitezan or Regencel) twice daily for 14 days. The proposed treatment had good aesthetic results, low cost and complexity, good pain tolerance and short recovery time. The disease has few treatment options available and among them the intralesional electrosurgery does not require technologies, has low cost and good aesthetic results.

Simultaneous determination of six vitamin A substances by multi-wavelength HPLC and application to different marine shellfishes

An HPLC-DAD method was developed for the simultaneous analytical determination of six vitamin A substances (retinol, retinyl acetate, retinyl palmitate, retinoic acid, retinal and β-carotene) and applied to the analysis of vitamin A substances in five marine shellfishes. The chromatographic column was a YMC-β carotene C30 column (250 × 4.6 mm, 3 µm), and the mobile phases were selected as A (methanol), B (ultrapure water) and C (methyl tert-butyl ether). The initial ratio of the mobile phase was A:B:C= 90:1:9, which was maintained for 8 min, while the ratio of the three was changed to A:B:C= 35:0:65 and continued for 8 min, and finally returned to the initial ratio within 0.1 min. Ultrasound-assisted direct extraction was investigated, and the optimal extraction conditions were determined by exploring different sample-to-liquid ratios, extractants, extraction times and extraction temperatures. The method was validated and the established assay showed good linearity in the range of 0.5–50 μg/mL with good precision and accuracy. The experimental results showed that retinol, retinyl palmitate and β-carotene were present in the shellfish and there were seasonal variations of vitamin A substances in different marine economic shellfish.

11 Evaluating Relationships Between Plasma and Liver Retinol Concentrations in the Beef Cow and Calf

Abstract In the young calf, vitamin A is particularly important for immune system maturation, and calves rely on colostrum at birth to supply vitamin A. Cow vitamin A status may influence colostral vitamin A concentrations, which can impact vitamin A status of their calves. Very little is understood about this relationship between beef cow and calf vitamin A status. Furthermore, limited data is available on how plasma and liver retinol concentrations in cattle are related to one another. The objective of this study was to examine relationships between liver and plasma retinol concentrations in the cow, calf, and within cow-calf pairs. Multiparous MARC II beef cows (n = 120; 6.4 ± 1.2 SD years of age; 592 ± 58 SD kg BW) in mid-gestation were provided supplemental vitamin A as retinyl acetate in a supplemental pellet at a rate of 21,125 ± 8,560 SD IU/d (current NASEM recommendation = 33,000 IU/d). Cows were individually fed using Calan gates a diet consisting of alfalfa hay, corn silage, and supplemental pellet for 144 d (111 d pre-calving and 32 d post-calving). Basal diet vitamin A concentration was 490 IU/kg of DM. Mean initial liver concentration of cows was 830 µg retinol/g of DM. To assess vitamin A status, liver biopsies and plasma samples were collected on cows and calves at the end of the supplemental period when calves averaged 32 ± 7 days of age (DOA). Pearson correlations were used to test for linear relationships between cow liver and plasma retinol concentrations, calf liver and plasma retinol concentrations, and liver and plasma retinol concentrations between the cow and her calf. No linear relationship (P = 0.10; r=0.16) was observed between liver and plasma retinol in cows. In the present study, mean cow liver retinol concentration (482 ± 182 SD µg/g of DM) fell within the current adequacy reference range of 300–700 µg/g of DM. Cow plasma retinol (272 ± 40 SD ng/mL) was slightly below the reference range of 300–800 ng/mL. A positive correlation (P &amp;lt; 0.01; r=0.37) was detected between calf liver (51 ± 27 SD µg/g of DM) and plasma (190 ± 47 ng/mL) retinol concentrations. Both were below what would be considered adequate (100–350 µg/g of DM in liver; 225–325 ng/mL in plasma) for calves at 32 DOA. There was a positive correlation (P &amp;lt; 0.01; r=0.31) between cow and calf liver retinol, suggesting that as cow retinol liver concentrations increased, calf liver retinol concentrations increased. It appears that despite cows having adequate liver retinol concentrations when 21,125 IU vitamin A/d was fed, it did not result in calf liver retinol stores that would be considered adequate given current reference ranges. USDA is an equal opportunity employer and provider.

The use of Microvit A in the Form of a Synthetic supplement for Metabolic Processes and Localization of Protein Substances

The purpose of this research is to study the present data on the effect of different dosages of vitamin A (retinol acetate) on the metabolism and localization of protein substances (protein) in the body of experimental animals (fattening bull calves). The authors use the concept of conversion of protein substances (protein) from the diet feed into the main nutrients of the edible part of the carcass (cuts) of bull calves fed on diets with pulp granules. The authors evaluate the morphological parameters of the animal after slaughter. For the experiment, 45 heads of black-and-white bull calves at the age of 12-13 months with a live weight of 270-290kg were selected. They were distributed according to the principle of similarity into three experimental groups of 15 heads each. The groups differed in diet, namely, an increase in the dosage of vitamin A in the second and third groups by 25 and 30% relative to the first group. According to the slaughter data and the study of the morphological composition of carcasses, the authors found that it was necessary to introduce vitamin A preparation into such diets. In this experiment, the authors used retinol acetate with the biological activity of 1 mln international units in 1 g, so that their content in the diets was 23-24 thousand international units per 100kg of live weight (optimally derived dose, depending on the live weight of the animal during the experiment). This contributed to an increase in the average daily weight gain of bull calves by 11.7% and an increase in carcass weight by 9.2%, including flesh weight by 11.1%. In the carcass flesh, the protein content increased by 15.4%, fat by 15.2%, and energy by 8.2%. The conversion rate of protein substances (protein) of the feed into the edible protein of the flesh of the carcass increased by 1.33% and the energy of the feed by 1.2%.

Gastro-Resistant Microparticles Produced by Spray-Drying as Controlled Release Systems for Liposoluble Vitamins.

In the present study, gastro-resistant microparticles (MPs) were produced using the spray-drying technique as controlled-release systems for some model liposoluble vitamins, including retinyl-palmitate, retinyl-acetate, β-carotene, cholecalciferol and α-tocopherol. The gastroprotective action of three different gastro-resistant excipients, the anionic methacrylic copolymer (Eudraguard®® Biotic, E1207), the cellulose acetate phthalate (CAP) and whey proteins (WPs), was compared. The latter was used to produce a novel delivery system manufactured with only food-derived components, such as milk, and showed several improvements over the two synthetic gastro-resistant agents. Scanning electron microscopy (SEM) images showed a quite homogeneous spherical shape of all microparticle batches, with an average diameter between 7 and 15 μm. FTIR analysis was used to evaluate the effective incorporation of vitamins within the microparticles and the absence of any degradation to the components of the formulation. The comparison graphs of differential scanning calorimetry (DSC) confirmed that the spray drying technique generates a solid in which the physical interactions between the excipients and the vitamins are very strong. Release studies showed a prominent pH-controlled release and partially a delayed-release profile. Ex vivo permeation studies of retinyl palmitate, retinyl acetate and α-tocopherol revealed greater transmucosal permeation capacity for microparticles produced with the WPs and milk.