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Objectives Methods Results Conclusion To achieve a more beautiful and younger appearance, reducing wrinkles is a key concern. The process of wrinkle formation is complex and the development of truly effective cosmetic ingredients to reduce wrinkles remains a challenge. Recent studies have revealed a close relationship between wrinkles and skin thinning, suggesting that preventing skin thinning could also prevent wrinkle formation. In this study, we examined the role of extracellular adenosine triphosphate (eATP) in the progression of thinning, as eATP reportedly increases skin ageing factors, such as senescence‐associated secreted phenotype (SASP) factors in epidermal cells. We determined the effects of Mentha piperita leaf extract on suppressing eATP to reduce thinning and wrinkles.Adenosine triphosphate (ATP) levels were measured in normal human epidermal keratinocytes (NHEK) in the presence of M. piperita leaf extract. Dryness, high pH, and UVB radiation were used as extrinsic ageing factors. Intrinsic skin ageing was evaluated by comparing cells from adults (AD‐NHEK) and newborns (NB‐NHEK). A placebo‐controlled in vivo study was carried out with a formulation containing 1% M. piperita leaf extract.The eATP levels were significantly higher in AD‐NHEK compared with that in NB‐NHEK cells. M. piperita leaf extract significantly decreased eATP levels in adult cells. Extrinsic ageing factors increased eATP levels in NHEK, whereas M. piperita leaf extract significantly suppressed eATP under all conditions. The active components of M. piperita leaf extract, luteolin glucuronide and rosmarinic acid, also decreased eATP. Moreover, compared with placebo lotion, M. piperita leaf extract‐formulated lotion markedly increased dermal thickness and reduced wrinkles associated with crow's feet and the neck area.We demonstrated for the first time that M. piperita leaf extract containing rosmarinic acid and luteolin‐7‐O‐glucuronide has the potential to reduce eATP release from epidermal keratinocytes. An increase in eATP was observed not only during inflammation but also during natural ageing. Furthermore, the in vivo experiment revealing that 1% M. piperita leaf extract‐containing lotion improved dermal thinning and wrinkles across multiple areas is attributed to the amelioration of dermal thinning. Thus, our data suggest the possibility of a novel cosmetic approach for reducing skin ageing by reducing eATP‐mediated dermal thinning. [ABSTRACT FROM AUTHOR]

In this research, three kinds of carbon fiber (CF) with lengths of 1, 3, and 25 mm were prepared for processing composite. The effect of submicron glass fiber addition (sGF) on mechanical properties of composites with different CF lengths was investigated and compared throughout static tests (i.e., bending, tensile, and impact), as well as the tension-tension fatigue test. The strengths of composites increased with the increase of CF length. However, there was a significant improvement when the fiber length changed from 1 to 3 mm. The mechanical performance of 3 and 25 mm was almost the same when having an equal volume fraction, except for the impact resistance. Comparing the static strengths when varying the sGF content, an improvement of bending strength was confirmed when sGF was added into 1 mm composite due to toughened matrix. However, when longer fiber was used and fiber concentration was high, mechanical properties of composite were almost dependent on the CF. Therefore, the modification effect of matrix due to sGF addition disappeared. In contrast to the static strengths, the fatigue durability of composites increased proportionally to the content of glass fiber in the matrix, regardless to CF length.

Cord factor (trehalose 6,6'-dimycolate, TDM) is an unique glycolipid with a trehalose and two molecules of mycolic acids in the mycobacterial cell envelope. Since TDM consists of two molecules of very long branched-chain 3-hydroxy fatty acids, the molecular mass ranges widely and in a complex manner. To characterize the molecular structure of TDM precisely and simply, an attempt was made to determine the mycolic acid subclasses of TDM and the molecular species composition of intact TDM by matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry for the first time. The results showed that less than 1 [micro]g mycolic acid methyl ester of TDM from nine representative species of mycobacteria and TDM from the same species was sufficient to obtain well-resolved mass spectra composed of pseudomolecular ions [[M+ Na].sup.+]. Although the mass ion distribution was extremely diverse, the molecular species of each TDM was identified clearly by constructing a molecular ion matrix consisting of the combination of two molecules of mycolic acids. The results showed a marked difference in the molecular structure of TDM among mycobacterial species and subspecies. TDM from Mycobacterium tuberculosis ([H.sub.37]Rv and Aoyama B) showed a distinctive mass pattern and consisted of over 60 molecular ions with [alpha]-, methoxy- and ketomycolate. TDM from Mycobacterium bovis BCG Tokyo 172 similarly showed over 35 molecular ions, but that from M. bovis BCG Connaught showed simpler molecular ion clusters consisting of less than 35 molecular species due to a complete lack of methoxymycolate. Mass ions due to TDM from M. bovis BOG Connaught and Mycobacterium kansasii showed a biphasic distribution, but the two major peaks of TDM from M. kansasii were shifted up two or three carbon units higher compared with M. bovis BCG Connaught. Within the rapid grower group, in TDM consisting of [alpha]-, keto- and wax ester mycolate from Mycobacterium phlei and Mycobacterium flavescens, the mass ion distribution due to polar mycolates was shifted lower than that from the Mycobacterium avium--intracellulare group. Since the physico-chemical properties and antigenic structure of mycolic acid of TDM affect the host immune responses profoundly, the molecular characterization of TDM by MALDI-TOF mass analysis may give very useful information on the relationship of glycolipid structure to its biological activity.

Humoral immune responses of active TB patients against six mycobacterial lipid antigens [trehalose 6,6'-dimycolate (TDM) from Mycobacterium boris BCG (TDM-T) and Mycobacterium avium complex (TDM-M), trehalose 6-monomycolate (TMM) from M. bovis BCG (TMM-T) and M. avium complex (TMM-M), triacyl (PL-2) and tetraacyl (PL-1) phosphatidylinositol dimannosides] were examined by ELISA. IgG antibodies of TB patients with active disease reacted against the six lipid antigens distinctively, but heterogeneously. If tests were combined and an overall positive was scored cumulatively when any one of the six tests was positive, a good discrimination between patient and normal subject was obtained. A positive result in any one of the six tests was obtained in 91.5 % of all 924 hospitalized patients and 93.3 % of 210 patients at their first visit to the outpatient clinic. The IgG antibody response differed considerably from patient to patient, and the response patterns were grouped into several types. IgG antibody levels paralleled the bacterial burden; however, the smear-negative (culture-positive) patient group also showed high positive rates and mean ELISA AA values against the six lipid antigens. There were also marked differences in positive rate and mean [DELTA]A values between cavity-positive and -negative groups, the former being higher than the latter. After anti-TB chemotherapy was initiated, IgG antibody levels decreased dramatically, paralleling the decrease in the amount of excretion of bacteria. Since multiple-antigen ELISA using particular lipid antigens was highly sensitive, and IgG antibody levels vary greatly at different stages of the disease, this technique is applicable for early diagnosis of smear-negative (and -positive) active TB and the prognosis for completion of anti-TB chemotherapy.

Direct estimation of the molecular mass of single molecular species of trehalose 6-monomycolate (TMM), a ubiquitous cell-wall component of mycobacteria, was performed by matrix-assisted laser desorption/ ionization time-of-flight (MALDI-TOF) mass spectrometry. When less than 1 [micro]g TMM was analysed by MALDI-TOF mass spectrometry, quasimolecular ions [M + Na]+ of each molecular species were demonstrated and the numbers of carbons and double bonds (or cyclopropane rings) were determined. Since the introduction of oxygen atoms such as carbonyl, methoxy and ester groups yielded the appropriate shift of mass ions, the major subclasses of mycolic acid ([alpha], methoxy, keto and wax ester) were identified without resorting to hydrolytic procedures. The results showed a marked difference in the molecular species composition of TMM among mycobacterial species. Unexpectedly, differing from other mycoloyl glycolipids, TMM from Mycobacterium tuberculosis showed a distinctive mass pattern, with abundant odd-carbon-numbered monocyclopropanoic (or monoenoic) [micro]-mycolates besides dicyclopropanoic mycolate, ranging from [C.sub.75] to [C.sub.85], odd- and even-carbon-numbered methoxymycolates ranging from [C.sub.83] to [C.sub.94] and even- and odd-carbon-numbered ketomycolates ranging from [C.sub.83] to [C.sub.90]. In contrast, TMM from Mycobacterium bovis (wild strain and BCG substrains) possessed even-carbon-numbered dicyclopropanoic [alpha]-mycolates. BCG Connaught strain lacked methoxymycolates almost completely. These results were confirmed by MALDI-TOF mass analysis of mycolic acid methyl esters liberated by alkaline hydrolysis and methylation of the original TMM. Wax ester-mycoloyl TMM molecular species were demonstrated for the first time as an intact form in the Mycobacterium avium--intracellulare group, M. phlei and M. flavescens. The M. avium--intracellulare group possessed predominantly [C.sub.85] and [C.sub.87] wax ester-mycoloyl TMM, while M. phlei and the rapid growers tested contained [C.sub.80], [C.sub.81], [C.sub.82] and [C.sub.83] wax ester-mycoloyl TMM. This technique has marked advantages in the rapid analysis of not only intact glycolipid TMM, but also the mycolic acid composition of each mycobacterial species, since it does not require any degradation process.