ARTICLE | doi:10.20944/preprints202101.0478.v1
Subject: Medicine & Pharmacology, Allergology Keywords: ocular drug delivery system; topical liposomes; posterior segment of the eye; safety and toler-ability; biologic activity; diabetic macular edema
Online: 25 January 2021 (10:48:51 CET)
Intravitreal injections (IVTs) of corticosteroids as triamcinolone acetonide (TA) are frequently used for the treatment of many vitreous and retinal disorders. However, IVTs are related to severe ocular complications. Lately, a topical ophthalmic TA loaded liposomes formulation (TALF) was designed to transport TA into the posterior segment of the eye when instilled in the ocular surface. To evaluate the safety, tolerability, and biologic activity of TALF, an animal study and a phase I clinical assay was performed. Moreover, four patients with diabetic macular edema (DME) were treated with TALF in order to explore the biologic activity of the formulation. No inflammation, lens opacity, swelling or intraocular pressure rising were recorded after the instillation of TALF in any of the animal or clinical study. Mainly, mild and transient adverse events such as dry eye (30%) and burning (30%) were reported. TALF improves significantly visual acuity and diminishes central foveal thickness in patients with DME. The current data demonstrate the safety, tolerability, and biologic activity of TALF. It seems that TALF can be used topically to treat vitreous and retinal diseases that respond to TA such as DME, avoiding the use of corticosteroids IVTs and its associated hazards.
ARTICLE | doi:10.20944/preprints201901.0116.v1
Subject: Medicine & Pharmacology, Pharmacology & Toxicology Keywords: Adipose tissue, Bioavailable, Menthol, Topical, TRPM8.
Online: 11 January 2019 (15:47:35 CET)
Recent evidences support a role of menthol, a TRPM8 agonist, in enhanced energy expenditure, thermogenesis and BAT-like activity in classical WAT depots in TRPM8 dependent and independent manner. The present study was designed to analyze whether oral and topical administration of menthol is bioavailable at subcutaneous adipose tissue and is sufficient to induce desired energy expenditure effects directly. GC-FID was performed to study menthol bioavailability in serum and subcutaneous white adipose tissue following oral and topical administration. Further, 3T3L1 adipocytes were treated with bioavailable menthol doses and different parameters (lipid accumulation, “browning/brite” and energy expenditure gene expression, metal analysis, mitochondrial complex’s gene expression) were studied. No difference was observed in serum levels but significant difference was seen in the menthol concentration on subcutaneous adipose tissues after oral and topical application. Menthol administration at bioavailable doses significantly increased “browning/brite” and energy expenditure phenotype, enhanced mitochondrial activity related gene expression, increased metal concentration but didn’t alter the lipid accumulation. Further, we used pharmacological antagonism based approach to study the TRPM8 involvement in menthol effect. In conclusion, the present study provides an evidence that bioavailable menthol after single oral and topical administration is sufficient to induce “brite” phenotype in subcutaneous adipose tissue.
ARTICLE | doi:10.20944/preprints202009.0389.v1
Subject: Medicine & Pharmacology, Ophthalmology Keywords: Graves’ ophthalmopathy; exophatlmos; intraocular pressure; topical medications
Online: 17 September 2020 (08:35:17 CEST)
Purpose: The evaluation of the efficacy of topical hypotensive treatment and/or systemic corticosteroids therapy in patients with elevated intraocular pressure and Graves’ orbitopathy (GO). Methods: 172 eyes in 86 individuals with duration of GO ≥ 3 months, intraocular pressure in either eye ≥ 25.0 mmHg and GO ranked ≥ 3 at least in one eye in modified CAS form, were included. The study subjects were divided into three treatment subgroups: subgroup I was administered latanoprost QD; subgroup II was administered a combined preparation of brimonidine and timolol BID; subgroup III was the control group, not receiving any topical hypotensive treatment. All the study participants received systemic treatment – intravenous corticosteroid therapy at the same dose, according to the EUGOGO guideline Results: On the final visit, the mean IOP value was significantly lower in all treatment subgroups comparing to the initial values. In both subgroups receiving topical treatment the IOP reduction was higher than in the control group receiving systemic corticosteroids only. However, the latanoprost eye drops decreased intraocular pressure more effectively than drops containing brimonidine and timolol. Conclusion: Topical ocular hypotensive treatment is effective in reducing intraocular pressure in GO and decreases intraocular pressure more effectively than systemic corticosteroid therapy alone.
Subject: Medicine & Pharmacology, Dermatology Keywords: topical steroid withdrawal; topical steroids; eczema; atopic dermatitis; skin microbiome; gut mi-crobiome; microbiome; biodiversity; skin allergy epidemic;
Online: 8 September 2021 (20:19:35 CEST)
We set up this preliminary study to evaluate one main question: could strengthening the microbiome have potential benefits for patients suffering with adverse effects after stopping long term topical steroid use? We aim to turn it into a much larger study if the results show promise. After commonly being prescribed for eczema, cessation of topical steroid use, especially after long periods of inappropriate use, can leave lasting adverse effects on the body and skin, known by some as topical steroid withdrawal (TSW). Furthermore, the subsequent withdrawal the body experiences when coming off the drug can leave lasting adverse effects on the body and skin, known by some as topical steroid withdrawal (TSW). This preliminary study involved seven human participants suffering with skin problems associated with TSW who approached Dr. Anja Gijsberts-Veens of their own volition because they were interested in more natural recovery methods. Five completed the study in full. Progress in skin condition was tracked by self-assessed symptom severity questionnaires filled out at the beginning and end of the study. The skin microbiome was addressed by using a 100% natural product shown in previous work to significantly increase skin microbiome biodiversity. Three participants implemented dietary changes and supplementation in response to guidance after fecal sample analysis to improve their gut health and biodiversity. The average improvement in skin symptoms for all participants was 40% and average symptom improvement ranged from 14% for Patient 5 to 92% for Patient 1. On average, the participants saw an improvement in 85% of their symptoms and a stagnation or regression in 11% and 4% respectively. We believe these results show enough promise to warrant expansion of this research to use a larger sample size, preferably 50+ participants, in future work. We also aim to swab the skin of participants to assess the effect on the skin microbiome from skin and gut treatments, as well as including more in-depth analysis of skin and gut microbiomes.
REVIEW | doi:10.20944/preprints202210.0034.v1
Subject: Biology, Agricultural Sciences & Agronomy Keywords: insect; genome; biopesticide; silencing; topical; gene target; validation
Online: 5 October 2022 (10:57:47 CEST)
Global crop yields are estimated to be reduced by 30–40% per year on account of plant pests and pathogens. Agricultural insect pests raise concerns about constraining global food security and climate changes contributing to the rise of infestation. The current management relies on plant breeding, associated or not with transgenes and chemical pesticides. Both approaches face serious technology obsolescence on the field due to resistance breakdown or development of insecticide resistance. The need for new Modes of Action (MoA) approaches in managing crop health grows each year, driven by market demands to reduce economic losses and phytosanitary requirements to meet the consumer perception. Disabling pest genes by sequence-specific expression silencing is considered a promising tool in the development of environment and health respectful biopesticides. The specificity conferred by long dsRNA-base solutions give support to minimizing effects on off-targeted genes in the insect pest genome and the target gene in non-target organisms (NTOs). In this review, we summarize the current status of gene silencing by RNA interference (RNAi) for agricultural control. More specifically, we focus on the engineering, development and application of gene silencing to control Lepidoptera by the employment of non-transforming dsRNA technologies. Despite some delivery and stability drawbacks of topical applications, we reviewed works showing convincing proof-of-concept results that point to imminent innovative solutions. Considerations about the regulamentation of the ongoing research on dsRNA-based pesticides to produce commercialized products for exogenous application are discussed. Academic and industry initiatives reveal a worthy effort to accomplish controlling Lepidoptera pests with this new mode of action to provide more sustainable and reliable technologies to field management. New data on genomics of this taxon encourage the increment of a customized target genes portfolio. As a case of study, we illustrate how dsRNA and associated methodologies could be applied to control an important Lepidopteran coffee pest.
REVIEW | doi:10.20944/preprints202210.0105.v1
Subject: Life Sciences, Microbiology Keywords: topical probiotics; skin microbiome; probiotics; biodiversity; microbiome; skin allergy; cosmetics
Online: 9 October 2022 (03:34:01 CEST)
In this paper we aim to help topical probiotics research and development achieve its potential as an incredible future solution for skin problems by investigating whether the current products on the market satisfy criteria for safe and effective use on the skin microbiome. As previously defined, this includes whether they use microbes known to be part of a healthy skin microbiome and in healthy amounts. In addition, we evaluate whether they contain live microbes, and therefore can be classified as probiotics according to the WHO’s definition. Using recent market analysis at least 84% of products do not contain live microbes. Of the products that appeared to use live microbes, they contained those used in research and development of probiotics for the gut. Due to the varying composition of each person’s microbiome, there is not a one size fits all probiotic solution. Personalisation of probiotics products is essential to satisfy the criteria for safe and effective use, but none of the products on the market, understandably, offer this. Upsetting the delicate ecosystem balance of the skin microbiome could have damaging effects and regulation could help to stop a loss of trust between consumers and cosmetics industry. Future work will perform an in-depth evaluation of the topical probiotics on the market in the EU, USA, and Canada. We will also investigate how to move the topic closer to achieving its potential by updating the criteria, including by discussing how to measure the success of a probiotic solution.
ARTICLE | doi:10.20944/preprints201801.0294.v1
Subject: Life Sciences, Other Keywords: behaviour; castration; cattle; dehorning; buccal meloxicam; pain; topical anaesthetic; weight gain
Online: 31 January 2018 (13:56:25 CET)
The use of pain relief during castration and dehorning of calves on commercial beef operations can be limited by constraints associated with the delivery of analgesic agents. As topical anaesthetic (TA) and buccal meloxicam (MEL) are now available in Australia, offering practical analgesic treatments for concurrent castration and dehorning of beef calves, a study was conducted to determine their efficacy in providing pain relief when applied alone or in combination. Weaner calves were randomly allocated to; (1) no castration and dehorning / positive control (CONP); (2) castration and dehorning / negative control (CONN); (3) castration and dehorning with buccal meloxicam (BM); (4) castration and dehorning with topical anaesthetic (TA); and (5) castration and dehorning with buccal meloxicam and topical anaesthetic (BMTA). Weight gain, paddock utilisation, lying activity and behaviour following treatment were measured. CONP and BMTA calves had significantly greater weight gain than CONN calves (P < 0.001). CONN calves spent less time lying compared to BMTA calves on all days (P < 0.001). All dehorned and castrated calves spent more time walking (P = 0.024) and less time eating (P < 0.001) compared to CONP calves. There was a trend for CONP calves to spend the most time standing and CONN calves to spend the least time standing (P = 0.059). There were also trends for the frequency of head turns to be lowest in CONP and BMTA calves (P = 0.098) and tail flicks to be highest in CONN and BM calves (P = 0.061). The findings of this study suggest that TA and MEL can improve welfare and production of calves following surgical castration and amputation dehorning.
ARTICLE | doi:10.20944/preprints202112.0486.v1
Subject: Biology, Entomology Keywords: Stemona collinsae; Non-Tai-Yak; Topical administration; Didehydrostemofoline; Alkaloids; Cockroach; Insecticide; MALDI IMS
Online: 30 December 2021 (12:39:41 CET)
Contact toxicity against Periplaneta americana has never been tested with S. collinsiae root extract. Hexane, dichloromethane, ethanol and water extracts were tested in final-instar nymphs and adult P. americana by topical application method. The dichloromethane extract showed the high-est potency of contact toxicity against the final-instar nymphs (41-100% corrected mortality at 48 hours), lowest LC50 (1.5±0.2 %w/v at 48 hours), and lowest LT50 (36.1±0.8 hours at 10%w/v) while the water crude extract lacked the contact toxicity (0-0% corrected mortality at 48 hours). Signs of toxicity, such as excited movement, trembling body, motionlessness, and swollen abdomen segment including irregularly extended foregut were found at the both stages of P. americana dropping with solutions of dichloromethane extract. Detection of didehydrostemofoline distri-bution using IMS revealed that didehydrostemofoline distributed in the tissue of the dead fi-nal-instar nymph and adult P. americana contacting with dichloromethane extract, but it was not found in tissue of euthanized P. americana which exposed to the water extract. Didehydrostemo-foline in the extract was a cause of toxicity signs and death of P. americana via a contact route. Thus, dichloromethane extract and didehydrostemofoline could be used as an active ingredient and chemical marker in aerosol and spray formulations for cockroach control.
REVIEW | doi:10.20944/preprints202103.0061.v1
Subject: Medicine & Pharmacology, Dermatology Keywords: vitamin D3, D2, calcitriol, oral, topical, serum 25-hydroxyvitamin D, psoriasis, skin diseases, UVB, phototherapy, sunshine, COVID-19, regulatory T lymphocytes
Online: 2 March 2021 (09:44:17 CET)
Vitamin D, sunshine and UVB phototherapy were first reported in the early 1900s to control psoriasis, cure rickets and cure tuberculosis (TB). Vitamin D also controlled asthma and rheumatoid arthritis with intakes ranging from 60,000 to 600,000 International Units (IU)/day. In the 1980s interest in treating psoriasis with vitamin D rekindled. Since 1985 four different oral forms of vitamin D (D2, D3, 1-hydroxyvitaminD3 (1(OH)D3) and 1,25-dihydroxyvitaminD3 (calcitriol)) and several topical formulations have been reported safe and effective treatments for psoriasis—as has UVB phototherapy and sunshine. In this review we show that many pre-treatment serum 25(OH)D concentrations fall within the current range of normal, while many post-treatment concentrations fall outside the upper limit of this normal (100 ng/ml). Yet, psoriasis patients showed significant clinical improvement without complications using these treatments. Current estimates of vitamin D sufficiency appear to underestimate serum 25(OH)D concentrations required for optimal health in psoriasis patients, while concentrations associated with adverse events appear to be much higher than current estimates of safe serum 25(OH)D concentrations. Based on these observations, the therapeutic index for vitamin D needs to be reexamined in the treatment of psoriasis and other diseases strongly linked to vitamin D deficiency, including COVID-19 infections, which may also improve safely with sufficient vitamin D intake or UVB exposure.