RESUMO
BACKGROUND: The kojyl 3-aminopropylphosphonic acid (KAP) was synthesized by kojic acid (KA) with a 3-aminopropylphosphonic acid. Which is more stable than KA and showed better skin penetration and anti-pigmentation efficacy in melanocytes. However, up till now, there have been no studies aimed at incorporating KAP into an emulsion system and evaluating its effectiveness. OBJECTIVE: We develop a novel skin-lightening agent using KAP as the active ingredient and a low-cytotoxic nanoemulsion as the delivery system in this study. METHOD: The sorbitan monooleate and polysorbate surfactants with polyethylene glycol (PEG) co-surfactant were used to generate a nanoemulsion system. RESULT: The transparency and particle size stability over various storage times indicate that the formulated nanoemulsions are suitable for long-term storage. Besides, results demonstrate that the anti-pigmentation function of KA and KAP-containing nanoemulsions (NE-KA and NEKAP) evidently outperformed that of the non-packed KA and KAP group. Despite having the lowest concentration among other treatments, NE-KAP was able to reduce melanin content to approximately 80% of the blank. CONCLUSION: Our findings suggest that this newly developed nanoemulsion containing KAP could potentially serve as a sustainable alternative to hydroquinone for treating dermal hyperpigmentation disorders in future applications.
RESUMO
BACKGROUND: Babesia gibsoni is the predominant tick-borne protozoan blood parasite affecting dogs throughout the Oriental region. Babesia gibsoni is transmitted by Haemaphysalis longicornis, whereas a similar role has been suggested for Rhipicephalus sanguineus. Haemaphysalis longicornis does not occur in Taiwan, but R. sanguineus is widely distributed on dogs. However, clinical cases of babesiosis are mainly restricted to the northern part of the island. The discrepancy between tick distribution and clinical cases stimulated us to investigate the tick species distribution on dogs in northern Taiwan, with the aim to identify the local vector for canine babesiosis. METHODS: Ticks were collected from stray dogs or free ranging pet dogs in northern Taiwan between 2015 and 2017 and, after identification, were tested for the presence of tick-borne Babesia parasites using PCR and reverse line blot (RLB) hybridisation. Moreover, engorged ticks collected from the dogs were incubated at 28 °C to allow them to oviposit. Their subsequent larval progeny was also examined by PCR/RLB. RESULTS: A total of 1085 ticks collected from 144 stray dogs at different residential areas consisted of 5 different species: H. hystricis (n = 435), R. sanguineus (n = 582), R. haemaphysaloides (n = 43), Amblyomma testudinarium (n = 14) and Ixodes ovatus (n = 11) were identified. Babesia gibsoni DNA was detected in H. hystricis females (10.3%), males (7.0%) and in 2.6% of the nymphs. One R. sanguineus female and one A. testudinarium female tick also carried B. gibsoni DNA. DNA of B. gibsoni was demonstrated in 11 out of 68 (16.2%) batches of larval ticks derived from engorged H. hystricus ticks only. Babesia vogeli DNA was detected only in R. sanguineus females (2.6%) and males (2.4%). DNA of B. vogeli was detected in 13 out of 95 (13.7%) batches of larval ticks derived from engorged R.sanguineus females. CONCLUSIONS: Babesia gibsoni DNA was detected in the larval progeny of H. hystricis ticks only, whereas B. vogeli was restricted to the larvae of R. sanguineus. This provides evidence for transovarial passage of B. gibsoni in H. hystricis and evidence that this tick does act as the local vector for this parasite on dogs in northern Taiwan where most cases of babesiosis are reported. The vectorial capacity of R. sanguineus for babesiosis is probably restricted to the transmission of B. vogeli only.