Lichen xanthones as models for new antifungal agents

Due to the emergence of multidrug-resistant pathogenic microorganisms, the search for new antimicrobial compounds plays an important role in current medicinal chemistry research. Inspired by lichen antimicrobial xanthones, a series of novel chlorinated xanthones was prepared using five chlorination methods (Methods A–E) to obtain different patterns of substitution in the xanthone scaffold. All the synthesized compounds were evaluated for their antimicrobial activity. Among them, 3-chloro-4,6-dimethoxy-1-methyl-9H-xanthen-9-one 15 showed promising antibacterial activity against E. faecalis (ATCC 29212 and 29213) and S. aureus ATCC 29213. 2,7-Dichloro-3,4,6-trimethoxy-1-methyl-9H-xanthen-9-one 18 revealed a potent fungistatic and fungicidal activity against dermatophytes clinical strains (T. rubrum, M. canis, and E. floccosum (MIC = 4–8 µg/mL)). Moreover, when evaluated for its synergistic effect for T. rubrum, compound 18 exhibited synergy with fluconazole (ΣFIC = 0.289). These results disclosed new hit xanthones for both antibacterial and antifungal activity.This work was partially supported through national funds provided by FCT/MCTES - Foundation for Science and Technology from the Ministry of Science, Technology, and Higher Education (PIDDAC) and the European Regional Development Fund (ERDF) through the COMPETE - Programa Operacional Factores de Competitividade (POFC) programme, under the Strategic Funding UID/Multi/04423/2013, the projects POCI-01-0145-FEDER-028736 and POCI-01-0145-FEDER-016790 (PTDC/MAR-BIO/4694/2014; 3599-PPCDT) in the framework of the programme PT2020, as well as by the project INNOVMAR - Innovation and Sustainability in the Management and Exploitation of Marine Resources (reference NORTE-01-0145-FEDER-000035, within Research Line NOVELMAR), supported by North Portugal Regional Operational Programme (NORTE 2020), under the PORTUGAL 2020 Partnership Agreement, through the European Regional Development Fund (ERDF). Diana I. S. P. Resende also acknowledge for her grant (NOVELMAR/BPD_2/2016-019) and Patrícia Pereira-Terra for her grant (NOVELMAR/BPD/2017/012)

Conhecimento Tradicional E Usos De Caryocar Brasiliense Cambess. (pequi) Por Quilombolas De Minas Gerais, Brasil: Subsídios Para O Manejo Sustentável

Local knowledge of biodiversity has been applied in support of research focused on utilizing and management of natural resources and promotion of conservation. Among these resources, Pequi (Caryocar brasiliense Cambess.) is important as a source of income and food for communities living in the Cerrado biome. In Pontinha, a “quilombola” community, which is located in the central region of State of Minas Gerais, Brazil, an ethnoecological study about Pequi was conducted to support initiatives for generating income for this community. Data were collected through semi-structured interviews, participant observation, and crossing. The most relevant uses of Pequi were family food (97%), soap production (67%), oil production (37%), medical treatments (17%), and trade (3%). Bees were the floral visitors with the highest Salience Index (S=0.639). Among frugivores that feed on unfallen fruits, birds showed a higher Salience (S=0.359) and among frugivores who use fallen fruits insects were the most important (S=0.574). Borers (folivorous caterpillars) that attack trunks and roots were the most common pests cited. According to the respondents, young individuals of Pequi are the most affected by fire due to their smaller size and thinner bark. Recognition of the cultural and ecological importance of Pequi has mobilized the community, which has shown interest in incorporating this species as an alternative source of income. © 2016, Instituto Internacional de Ecologia. All rights reserved.762511519FAPEMIG, Fundação de Amparo à Pesquisa do Estado de Minas Gerai

Analytical results for coupled map lattices with long-range interactions

We obtain exact analytical results for lattices of maps with couplings that decay with distance as $r^{-\alpha}$. We analyze the effect of the coupling range on the system dynamics through the Lyapunov spectrum. For lattices whose elements are piecewise linear maps, we get an algebraic expression for the Lyapunov spectrum. When the local dynamics is given by a nonlinear map, the Lyapunov spectrum for a completely synchronized state is analytically obtained. The critical lines characterizing the synchronization transition are determined from the expression for the largest transversal Lyapunov exponent. In particular, it is shown that in the thermodynamical limit, such transition is only possible for sufficiently long-range interactions, namely, for $\alpha\le alpha_c<d$, where $d$ is the lattice dimension.Comment: 4 pages, 2 figures, corrections included. Phys. Rev. E 68, 045202(R) (2003); correction in pres

Breast Density In Women With Premature Ovarian Failure Or Postmenopausal Women Using Hormone Therapy: Analytical Cross-sectional Study [densidade Mamária Em Mulheres Com Falência Ovariana Prematura Ou Na Pós-menopausa E Em Uso De Terapia Hormonal: Estudo Transversal Analítico]

Context and objective: Studies on postmenopausal women have reported increased risk of breast cancer relating to the type and duration of hormone therapy (HT) used. Women with premature ovarian failure (POF) represent a challenge, since they require prolonged HT. Little is known about the impact of prolonged HT use on these women's breasts. This study aimed to evaluate the effects of one type of HT on the breast density of women with POF, compared with postmenopausal women. Design and setting: Cross-sectional study at the Department of Obstetrics and Gynecology, Universidade Estadual de Campinas (Unicamp). Methods: 31 women with POF and 31 postmenopausal women, all using HT consisting of conjugated equine estrogen combined with medroxyprogesterone acetate, and matched according to HT duration, were studied. Mammography was performed on all subjects and was analyzed by means of digitization or Wolfe's classification, stratified into two categories: Non-dense (N1 and P1 patterns) and dense (P2 and Dy). Results: No significant difference in breast density was found between the two groups through digitization or Wolfe's classification. From digitization, the mean breast density was 24.1% ± 14.6 and 18.1% ± 17.2 in the POF and postmenopausal groups, respectively (P = 0.15). Wolfe's classification identified dense breasts in 51.6% and 29.0%, respectively (P = 0.171). Conclusion: There was no difference in breast density between the women with POF and postmenopausal women, who had used HT for the same length of time. These results may help towards compliance with HT use among women with POF.1284211214Rossouw, J.E., Anderson, G.L., Prentice, R.L., Risks and benefits of estrogen plus progestin in healthy postmenopausal women: Principal results From the Women's Health Initiative randomized controlled trial (2002) JAMA, 288 (3), pp. 321-333Beral, V., Breast cancer and hormone-replacement therapy in the Million Women Study (2003) Lancet, 362 (9382), pp. 419-427. , Million Women Study CollaboratorsConner, P., Svane, G., Azavedo, E., Mammographic breast density, hormones, and growth factors during continuous combined hormone therapy (2004) Fertil Steril, 81 (6), pp. 1617-1623Chen, F.P., Cheung, Y.C., Teng, L.F., Soong, Y.K., The relationship between mammographic density and duration of hormone therapy: Effects of estrogen and estrogen-progestin (2005) Hum Reprod, 20 (6), pp. 1741-1745Harvey, J., Scheurer, C., Kawakami, F.T., Hormone replacement therapy and breast density changes (2005) Climacteric, 8 (2), pp. 185-192Junkermann, H., von Holst, T., Lang, E., Rakov, V., Influence of different HRT regimens on mammographic density (2005) Maturitas, 50 (2), pp. 105-110Christodoulakos, G.E., Lambrinoudaki, I.V., Vourtsi, A.D., The effect of low dose hormone therapy on mammographic breast density (2006) Maturitas, 54 (1), pp. 78-85Kavanagh, A.M., Mitchell, H., Giles, G.G., Hormone replacement therapy and accuracy of mammographic screening (2000) Lancet, 355 (9200), pp. 270-274Banks, E., Hormone replacement therapy and the sensitivity and specificity of breast cancer screening: A review (2001) J Med Screen, 8 (1), pp. 29-34Warren, R., Hormones and mammographic breast density (2004) Maturitas, 49 (1), pp. 67-78Armitage, M., Nooney, J., Evans, S., Recent concerns surrounding HRT (2003) Clin Endocrinol (Oxf), 59 (2), pp. 145-155Mann, R.D., Hormone replacement therapy and breast cancer risk: Studies of the last fifteen years (1992) Hormone replacement therapy and breast cancer risk, pp. 1-8. , In: Mann RD, editor, New Jersey: Parthenon Publishing GroupBoyd, N.F., Byng, J.W., Jong, R.A., Quantitative classification of mammographic densities and breast cancer risk: Results from the Canadian National Breast Screening Study (1995) J Natl Cancer Inst, 87 (9), pp. 670-675Byrne, C., Schairer, C., Wolfe, J., Mammographic features and breast cancer risk: Effects with time, age, and menopause status (1995) J Natl Cancer Inst, 87 (21), pp. 1622-1629Maskarinec, G., Meng, L., A case-control study of mammographic densities in Hawaii (2000) Breast Cancer Res Treat, 63 (2), pp. 153-161Vachon, C.M., Kuni, C.C., Anderson, K., Anderson, V.E., Sellers, T.A., Association of mammographically defined percent breast density with epidemiologic risk factors for breast cancer (United States) (2000) Cancer Causes Control, 11 (7), pp. 653-662Noh, J.J., Maskarinec, G., Pagano, I., Cheung, L.W., Stanczyk, F.Z., Mammographic densities and circulating hormones: A cross-sectional study in premenopausal women (2006) Breast, 15 (1), pp. 20-28Laya, M.B., Gallagher, J.C., Schreiman, J.S., Effect of postmenopausal hormonal replacement therapy on mammographic density and parenchymal pattern (1995) Radiology, 196 (2), pp. 433-437Collaborative Group on Hormonal Factors in Breast Cancer (1997) Lancet, 350 (9084), pp. 1047-1059. , Breast cancer and hormone replacement therapy: collaborative reanalysis of data from 51 epidemiological studies of 52,705 women with breast cancer and 108,411 women without breast cancerMarugg, R.C., van der Mooren, M.J., Hendriks, J.H., Rolland, R., Ruijs, S.H., Mammographic changes in postmenopausal women on hormonal replacement therapy (1997) Eur Radiol, 7 (5), pp. 749-755Koukoulis, G.N., Hormone replacement therapy and breast cancer risk (2000) Ann N Y Acad Sci, 900, pp. 422-428Lundström, E., Wilczek, B., von Palffy, Z., Söderqvist, G., von Schoultz, B., Mammographic breast density during hormone replacement therapy: Effects of continuous combination, unopposed transdermal and low-potency estrogen regimens (2001) Climacteric, 4 (1), pp. 42-48Greendale, G.A., Palla, S.L., Ursin, G., The association of endogenous sex steroids and sex steroid binding proteins with mammographic density: Results from the Postmenopausal Estrogen/Progestin Interventions Mammographic Density Study (2005) Am J Epidemiol, 162 (9), pp. 826-834de Moraes-Ruehsen, M., Jones, G.S., Premature ovarian failure (1967) Fertil Steril, 18 (4), pp. 440-461Cymberknoh, M., Mamografia digital (1994) Mastologia atual, pp. 75-78. , In: Dias EN, Caleffi M, Silva HMS, Figueira-Filho ASS, eds., Rio de Janeiro: RevinterWolfe, J.N., Breast patterns as an index of risk for developing breast cancer (1976) AJR Am J Roentgenol, 126 (6), pp. 1130-1137Snedecor, W.G., Cochram, W.G., The comparison of two samples (1989) Statistical methods, pp. 83-102. , In: Snedecor WG, Cochram WG, editors., 8thed Ames: Iowa State University PressPersson, I., Thurfjell, E., Holmberg, L., Effect of estrogen and estrogen-progestin replacement regimens on mammographic breast parenchymal density (1997) J Clin Oncol, 15 (10), pp. 3201-3207Harvey, J.A., Bovbjerg, V.E., Quantitative assessment of mammographic breast density: Relationship with breast cancer risk (2004) Radiology, 230 (1), pp. 29-4

Higher Order Evaluation of the Critical Temperature for Interacting Homogeneous Dilute Bose Gases

We use the nonperturbative linear \delta expansion method to evaluate analytically the coefficients c_1 and c_2^{\prime \prime} which appear in the expansion for the transition temperature for a dilute, homogeneous, three dimensional Bose gas given by T_c= T_0 \{1 + c_1 a n^{1/3} + [ c_2^{\prime} \ln(a n^{1/3}) +c_2^{\prime \prime} ] a^2 n^{2/3} + {\cal O} (a^3 n)\}, where T_0 is the result for an ideal gas, a is the s-wave scattering length and n is the number density. In a previous work the same method has been used to evaluate c_1 to order-\delta^2 with the result c_1= 3.06. Here, we push the calculation to the next two orders obtaining c_1=2.45 at order-\delta^3 and c_1=1.48 at order-\delta^4. Analysing the topology of the graphs involved we discuss how our results relate to other nonperturbative analytical methods such as the self-consistent resummation and the 1/N approximations. At the same orders we obtain c_2^{\prime\prime}=101.4, c_2^{\prime \prime}=98.2 and c_2^{\prime \prime}=82.9. Our analytical results seem to support the recent Monte Carlo estimates c_1=1.32 \pm 0.02 and c_2^{\prime \prime}= 75.7 \pm 0.4.Comment: 29 pages, 3 eps figures. Minor changes, one reference added. Version in press Physical Review A (2002

Asymptotically Improved Convergence of Optimized Perturbation Theory in the Bose-Einstein Condensation Problem

We investigate the convergence properties of optimized perturbation theory, or linear $\delta$ expansion (LDE), within the context of finite temperature phase transitions. Our results prove the reliability of these methods, recently employed in the determination of the critical temperature T_c for a system of weakly interacting homogeneous dilute Bose gas. We carry out the explicit LDE optimized calculations and also the infrared analysis of the relevant quantities involved in the determination of $T_c$ in the large-N limit, when the relevant effective static action describing the system is extended to O(N) symmetry. Then, using an efficient resummation method, we show how the LDE can exactly reproduce the known large-N result for $T_c$ already at the first non-trivial order. Next, we consider the finite N=2 case where, using similar resummation techniques, we improve the analytical results for the nonperturbative terms involved in the expression for the critical temperature allowing comparison with recent Monte Carlo estimates of them. To illustrate the method we have considered a simple geometric series showing how the procedure as a whole works consistently in a general case.Comment: 38 pages, 3 eps figures, Revtex4. Final version in press Phys. Rev.

Self-Similar Factor Approximants

The problem of reconstructing functions from their asymptotic expansions in powers of a small variable is addressed by deriving a novel type of approximants. The derivation is based on the self-similar approximation theory, which presents the passage from one approximant to another as the motion realized by a dynamical system with the property of group self-similarity. The derived approximants, because of their form, are named the self-similar factor approximants. These complement the obtained earlier self-similar exponential approximants and self-similar root approximants. The specific feature of the self-similar factor approximants is that their control functions, providing convergence of the computational algorithm, are completely defined from the accuracy-through-order conditions. These approximants contain the Pade approximants as a particular case, and in some limit they can be reduced to the self-similar exponential approximants previously introduced by two of us. It is proved that the self-similar factor approximants are able to reproduce exactly a wide class of functions which include a variety of transcendental functions. For other functions, not pertaining to this exactly reproducible class, the factor approximants provide very accurate approximations, whose accuracy surpasses significantly that of the most accurate Pade approximants. This is illustrated by a number of examples showing the generality and accuracy of the factor approximants even when conventional techniques meet serious difficulties.Comment: 22 pages + 11 ps figure