Promotion of glyoxylic acid penetration into human hair by glycolic acid.

OBJECTIVE: Glyoxylic acid (GA) is widely used as a straight perming agent for hair care products, however, advanced GA penetration-enhancing agents are desired due to the peculiar odour and hair colour fading caused by the continuous use of GA products. Hence, it is important to develop a penetration-enhancing agent that helps minimize the GA concentration. We have found that the combined use of GA and glycolic acid (GCA) has a strong hair straightening effect. METHODS: Straightening hair test was carried out to the evaluation of the effect of additives. Liquid chromatography-mass spectrometry (LC/MS) was performed to quantify the GA penetration amount into human hair. Attenuated total reflection (ATR) Fourier transform-infrared spectroscopy (FT-IR) and FT-IR microscope were implemented to estimate the localization of GA in the hair. RESULTS: Straightening hair tests indicated that the hair straightening effect by GA was enhanced by the presence of GCA. LC/MS results showed that the addition of GCA enhanced the amount of GA that penetrated human hair by about four times. ATR FT-IR and FT-IR microscope measurements indicated that GA was localized more in the innermost region of hair (medulla) than the cortex and cuticle. The GA accumulated in the medulla disappeared after a hair straightener treatment at 180°C due to the chemical reaction. CONCLUSIONS: The GA penetration-enhancing effect of GCA is worth investigating to reduce the GA concentration in products for more comfortable use.

OBJECTIF: L'acide glyoxylique (AG) est largement utilisé en tant qu'agent de lissage pour les produits de soins capillaires. Cependant, des agents avancés améliorant la pénétration de l'AG sont souhaités en raison de l'odeur particulière et de la décoloration des cheveux causées par l'utilisation continue de produits à base d'AG. Il est donc important de mettre au point un agent améliorant la pénétration qui contribue à minimiser la concentration d'AG. Nous avons constaté que l'utilisation combinée de l'AG et de l'acide glycolique (AGC) a un fort effet lissant sur les cheveux. MÉTHODES: Un test de lissage des cheveux a été effectué pour évaluer l'effet des additifs. Une chromatographie en phase liquide avec spectrométrie de masse (liquid chromatography-mass spectrometry, LC/MS) a été réalisée pour quantifier le volume de pénétration de l'AG dans les cheveux humains. Une spectroscopie infrarouge à transformée de Fourier (Fourier transform-infrared spectroscopy, FT-IR) à réflexion totale atténuée (RTA) et un microscope FT-IR ont été adoptés pour estimer la localisation de l'AG dans les cheveux. RÉSULTATS: Les tests de lissage des cheveux ont indiqué que l'effet de lissage des cheveux de l'AG était renforcé par la présence d'AGC. Les résultats de la LC/MS ont montré que l'ajout d'AGC augmentait d'environ quatre fois la quantité d'AG pénétrant dans les cheveux humains. Les mesures de la FT-IR à RTA et du microscope FT-IR ont indiqué que l'AG était plus localisé dans la région la plus interne du cheveu (médulla) que dans le cortex et la cuticule. L'AG accumulé dans la médulla a disparu après un traitement au lisseur à cheveux à 180 °C en raison de la réaction chimique. CONCLUSIONS: L'effet d'amélioration de la pénétration de l'AG observé avec l'AGC mérite d'être étudié afin de réduire la concentration d'AG dans les produits pour une utilisation plus confortable.

A new shrew mole species of the genus Uropsilus (Eulipotyphla: Talpidae) from northwestern Vietnam.

A new medium-sized shrew mole species of the genus Uropsilus from Mount Fansipan, Hoang Lien National Park, Lao Cai Province, northwestern Vietnam is described based on morphological and molecular differences. Uropsilus fansipanensis sp. nov. is distinguished from the other Uropsilus species by the combination of the following features: the dorsum is lightly reddish-brown and venter is dark gray; the dark gray tail is long and slender, with a scattered white base and short bristle hairs; orbital process is oriented upwards posteriorly; lacrimal foramen is well developed and much larger than infraorbital foramen; the lower first premolar is approximately the same size as the lower third premolar. Genetic distances in terms of mitochondrial cytochrome b from other Uropsilus species presented pairwise divergences from 8.63 to 20.70%. To date, the new species is known to exist only in the type locality of Mt. Fansipan, a wet and cold temperate climate area with an upper montane forest at an elevation of approximately 2900 m, forming the southernmost distribution of the genus Uropsilus.

Detection of tetrodotoxin (TTX) from two copepods infecting the grass puffer Takifugu niphobles: TTX attracting the parasites?

In May 2002, two parasitic copepods, Pseudocaligus fugu and Taeniacanthus sp., were collected from the body surface and gill of the grass puffer Takifugu niphobles, respectively, in Takehara city, Hiroshima Prefecture, faced with Seto Inland Sea located in the western part of Japan. To them was added 5 ml of 0.1% acetic acid, then the suspension was subjected to ultrasonic disruption with an ultrasonicator for 10 min. The resulting mixture was heated in a boiling water bath for 10 min, and then centrifuged. The supernatant was concentrated under reduced pressure, and loaded on to a Sep-Pak plus C18 Environmental Cartridge (Waters). The unbound fraction was analyzed by HPLC and gas chromatography-mass spectrometry (GC-MS) for tetrodotoxin (TTX). It was rather unexpectedly revealed from these results that this fraction was comprised of TTX and its analogues. As far as we know, this is the first record to show the existence of TTX in the copepods. In addition, relationships between the more and less than the average number of the two parasites and the toxicity of its skin mucus of the host were examined by student's t-test. In P. fugu, the average number per host was 13.9, and those are 520.7 (n=9) and 269.0 MU/g (n=22), respectively. A highly significant difference between them was detected at p-value 0.0011. In contrast, as for Taeniacanthus sp., the average number was 2.7, and those were 338.0 (n=14) and 345.5 MU/g (n=17), respectively. No significant difference was detected in Taeniacanthus sp. The high host-specificity of P. fugu on the toxic puffer and the present bioassay of its skin mucus suggest a possibility that TTXs may attract the parasite.