Application of tetra-isopalmitoyl ascorbic acid in cosmetic formulations: Stability studies and in vivo efficacy

Liposoluble vitamin C derivatives, such as tetra-isopalmitoyl ascorbic acid (IPAA), are often used in dermocosmetic products due to their higher stability than vitamin C free form as well as its proposed effects in skin; however, there are no studies analyzing IPAA stability or its in vivo effects when present in dermocosmetic formulations. Thus, this study aimed to evaluate chemical stability and pre-clinical and clinical efficacy of dermocosmetic formulations containing IPAA in skin hydration and microrelief. Chemical stability of the formulations added with 1% IPAA was evaluated by heat stress during 35 days by HPLC. For pre-clinical evaluation, experimental formulations were topically applied on hairless skin mice during 5 days and animal skins were analyzed by non-invasive biophysic techniques (water content of stratum corneum, TEWL, viscoelasticity, and microrelief) and by histopathological studies. For clinical efficacy tests, the formulations were topically applied to the forearm and face of human volunteers, and 3 h and 15 days after applications, the skins were evaluated by the same non-invasive techniques mentioned before. Results showed that formulations containing IPAA had medium stability and had pronounced moisturizing effects on stratum corneum and on viable epidermis. These formulations also improved skin microrelief especially in relation to skin smoothness and roughness. (C) 2012 Elsevier B.V. All rights reserved.

N-4-Phenyl-substituted 2-acetylpyridine thiosemicarbazones: Cytotoxicity against human tumor cells, structure-activity relationship studies and investigation on the mechanism of action

N-4-Phenyl 2-acetylpyridine thiosemicarbazone (H2Ac4Ph; N-(phenyl)-2-(1-(pyridin-2-yl)ethylidene) hydrazinecarbothioamide) and its N-4-ortho-, -meta- and -para-fluorophenyl (H2Ac4oFPh, H2Ac4mFPh, H2Ac4pFPh), N-4-ortho-, -meta- and -para-chlorophenyl (H2Ac4oClPh, H2Ac4mClPh, H2Ac4pClPh), N-4-ortho-, -meta- and -para-iodophenyl (H2Ac4oIPh, H2Ac4mIPh, H2Ac4pIPh) and N-4-ortho-, -meta- and -para-nitrophenyl (H2Ac4oNO(2)Ph, H2Ac4mNO(2)Ph, H2Ac4pNO(2)Ph) derivatives were assayed for their cytotoxicity against human malignant breast (MCF-7) and glioma (T98G and U87) cells. The compounds were highly cytotoxic against the three cell lineages (IC50: MCF-7, 52-0.16 nM; T98G, 140-1.0 nM; U87, 160-1.4 nM). All tested thiosemicarbazones were more cytotoxic than etoposide and did not present any haemolytic activity at up to 10(-5) M. The compounds were able to induce programmed cell death. H2Ac4pClPh partially inhibited tubulin assembly at high concentrations and induced cellular microtubule disorganization. (C) 2012 Elsevier Ltd. All rights reserved.

The Panama microplate, island studies and relictual species of Melipona (Melikerria) (Hymenoptera: Apidae: Meliponini)

The endemic stingless honey-making bee Melipona (Melikerria) insularissp.n. on Coiba and Rancheria Islands in Pacific Panama is described, together with the proposed sister species, M. ambigua sp.n. from northeast Colombia. The Coiba Island group and Panama mainland were surveyed, yielding one meliponine endemic (M. insularissp.n.) and six meliponine genera and species. The poor Coiba fauna of amphibians and birds corresponds to the poor social bee fauna and suggests habitat barriers generally precluded recolonization from the mainland during glacial periods. Many animals became extinct, yet some remain as relicts. Melipona insularissp.n. was isolated on accreted terranes of Coiba rainforest in the Panama microplate. Morphology suggests that M. insularissp.n. is not a direct descendant of the San Blas-E. Panama endemic Melikerria, M. triplaridis. A phylogenetic hypothesis corroborates disjunct distributions. Rainforest endemics such as Peltogyne purpurea (Fabaceae) and Ptilotrigona occidentalis (Apidae, Meliponini) also occur as relictual, disjunct populations in Central and South America. These may have been isolated before accelerated biotic exchange began 2.4 Ma. Our work supports the geological findings of both a volcanic arc and the San Blas massif providing a substantial bridge for Melikerria from Colombia and Panama in Eocene to Miocene times. We suggest there have been taxon cycles permitting recolonization during glaciations, whereby colonies of M. insularissp.n. were able to recolonize Rancheria, a 250 ha island, 2 km from Coiba. However, rafting colonies nesting in trees, carried on vegetation mats, may have produced founding populations of Melipona in Central America and on oceanic islands such as Coiba.

Polymorphous low-grade adenocarcinoma: an analysis of epidemiological studies and hints for pathologists

Abstract Background This study is an analysis of the prevalence of polymorphous low grade adenocarcinoma (PLGA) in epidemiological surveys of salivary tumors published in the English language from 1992 to 2012. Methods These surveys included studies from different researchers, countries and continents. The 57 surveys for which it was possible to calculate the percentage of PLGAs among all malignant minor salivary gland tumors (MMSGT) were included in this review. Results The statistical analyses show significant differences in the PLGA percentage by time period, country and continent in the studies included in this review. The percentage of PLGAs among MMSGTs varied among the studies, ranging from 0.0% to 46.8%. PLGA rates have varied over the period studied and have most recently increased. The frequency of reported PLGA cases also varied from 0.0% to 24.8% by the country in which the MMSGT studies were performed. The PLGA percentages also varied significantly by continent, with frequencies ranging from 3.9% in Asia to 20.0% in Oceania Conclusion Based on these results, we concluded that although the accuracy of PLGA diagnoses has improved, they remain a challenge for pathologists. To facilitate PLGA diagnoses, we have therefore made some suggestions for pathologists regarding tumors composed of single-layer strands of cells that form all of the histological patterns present in the tumor, consistency of the cytological appearance and uniformly positive CK7, vimentin and S100 immunohistochemistry, which indicate a single PLGA phenotype. Virtual slide The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1059098656858324

In vitro evaluation, in vivo quantification, and microbial diversity studies of nutritional strategies for reducing enteric methane production

The main objective of the present work was to study nutritive strategies for lessening the CH4 formation associated to ruminant tropical diets. In vitro gas production technique was used for evaluating the effect of tannin-rich plants, essential oils, and biodiesel co-products on CH4 formation in three individual studies and a small chamber system to measure CH4 released by sheep for in vivo studies was developed. Microbial rumen population diversity from in vitro assays was studied using qPCR. In vitro studies with tanniniferous plants, herbal plant essential oils derived from thyme, fennel, ginger, black seed, and Eucalyptus oil (EuO) added to the basal diet and cakes of oleaginous plants (cotton, palm, castor plant, turnip, and lupine), which were included in the basal diet to replace soybean meal, presented significant differences regarding fermentation gas production and CH4 formation. In vivo assays were performed according to the results of the in vitro assays. , when supplemented to a basal diet (Tifton-85 hay sp, corn grain, soybean meal, cotton seed meal, and mineral mixture) fed to adult Santa Ines sheep reduced enteric CH4 emission but the supplementation of the basal diet with EuO did not affect ( > 0.05) methane released. Regarding the microbial studies of rumen population diversity using qPCR with DNA samples collected from the in vitro trials, the results showed shifts in microbial communities of the tannin-rich plants in relation to control plant. This research demonstrated that tannin-rich , essential oil from eucalyptus, and biodiesel co-products either in vitro or in vivo assays showed potential to mitigate CH4 emission in ruminants. The microbial community study suggested that the reduction in CH4 production may be attributed to a decrease in fermentable substrate rather than to a direct effect on methanogenesis.

A VALIDATED HPLC ANALYTICAL METHOD FOR THE ANALYSIS OF SOLASONINE AND SOLAMARGINE IN IN VITRO SKIN PENETRATION STUDIES

To assess topical delivery studies of glycoalkaloids, an analytical method by HPLC-UV was developed and validated for the determination of solasonine (SN) and solamargine (SM) in different skin layers, as well as in a topical formulation. The method was linear within the ranges 0.86 to 990.00 mu g/mL for SN and 1.74 to 1000.00 mu g/mL for SM (r = 0.9996). Moreover, the recoveries for both glycoalkaloids were higher than 88.94 and 93.23% from skin samples and topical formulation, respectively. The method developed is reliable and suitable for topical delivery skin studies and for determining the content of SN and SM in topical formulations.

Three in one: fixing marine nematodes for ecological, molecular, and morphological studies

Multidisciplinary benthic studies are still hindered by the lack of a unique fixative that satisfactorily preserves morphology and DNA, and that is simultaneously adequate for ecological surveys. The objective of this study is to test the performance of five fixatives: formalin, ethanol, dimethylsulfoxide with EDTA and NaCl salts (DESS), methanol with acetic acid (METHAC), and ethanol with acetic acid (ETHAC), for the preservation of estuarine and exclusively marine nematode assemblages for morphological, molecular, and ecological studies. The presence of the stain rose bengal in each fixative was also evaluated in the yield of PCR reactions. For molecular analyses, one species of each habitat was considered. Results revealed that fixative performance for morphological studies is habitat-and species-dependent. For studies of estuarine sediment nematodes, we recommend the use of pure ethanol, because it caused little morphological distortion (<10% of the assemblage), preserved all the species for ecological studies, and yielded high quality DNA sequences. For studies of exclusively marine environments, METHAC or DESS are the most adequate. The first performed better for morphological and ecological surveys, whereas the second was more appropriate for molecular research. For ecological studies, DESS should be used in comparison with formalin, in order to cross check the results. Finally, staining of samples with rose bengal is not recommended, because it hindered DNA amplification regardless of the fixative used.

Surgical and postmortem pathology studies: contribution for the investigation of temporal lobe epilepsy

Pathology studies in epilepsy patients bring useful information for comprehending the physiopathology of various forms of epilepsy, as well as aspects related to response to treatment and long-term prognosis. These studies are usually restricted to surgical specimens obtained from patients with refractory focal epilepsies. Therefore, most of them pertain to temporal lobe epilepsy (TLE) with mesial temporal sclerosis (MTS) and malformations of cortical development (MCD), thus providing information of a selected group of patients and restricted regions of the brain. Postmortem whole brain studies are rarely performed in epilepsy patients, however they may provide extensive information on brain pathology, allowing the analysis of areas beyond the putative epileptogenic zone. In this article, we reviewed pathology studies performed in epilepsy patients with emphasis on neuropathological findings in TLE with MTS and MCD. Furthermore, we reviewed data from postmortem studies and discussed the importance of performing these studies in epilepsy populations.

A validated HPLC analytical method for the analysis of solasonine and solamargine in in vitro skin penetration studies

To assess topical delivery studies of glycoalkaloids, an analytical method by HPLC-UV was developed and validated for the determination of solasonine (SN) and solamargine (SM) in different skin layers, as well as in a topical formulation. The method was linear within the ranges 0.86 to 990.00 µg/mL for SN and 1.74 to 1000.00 µg/mL for SM (r = 0.9996). Moreover, the recoveries for both glycoalkaloids were higher than 88.94 and 93.23% from skin samples and topical formulation, respectively. The method developed is reliable and suitable for topical delivery skin studies and for determining the content of SN and SM in topical formulations.