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101.
Luciana Dos S. D. de Oliveira Marcos José da Silva Margareth F. de Sales 《Brittonia》2013,65(3):310-329
A synopsis of the tribe Hureae is presented with nomenclatural updates, a discussion of diagnostic features, and summaries of geographical distributions. This study is based on the analysis of approximately 300 voucher specimens, including collections and photographs of types, in addition to bibliographic documentation. Seventeen species distributed in three genera were recognized: Algernonia (11 species), Hura (2), and Ophthalmoblapton (4). All species are American with the majority distributed within the Atlantic Forest, particularly in southeastern Brazil. A key for the identification of genera and species is provided along with illustrations, information on the geographic distributions and conservation status. Lectotypification for Algernonia leandrii is proposed. 相似文献
102.
Naiara Akizu Nuri?M. Shembesh Tawfeg Ben-Omran Laila Bastaki Asma Al-Tawari Maha?S. Zaki Roshan Koul Emily Spencer Rasim?Ozgur Rosti Eric Scott Elizabeth Nickerson Stacey Gabriel Gilberto da?Gente Jiang Li Matthew?A. Deardorff Laura?K. Conlin Margaret?A. Horton Elaine?H. Zackai Elliott?H. Sherr Joseph?G. Gleeson 《American journal of human genetics》2013,92(3):392-400
The corpus callosum is the principal cerebral commissure connecting the right and left hemispheres. The development of the corpus callosum is under tight genetic control, as demonstrated by abnormalities in its development in more than 1,000 genetic syndromes. We recruited more than 25 families in which members affected with corpus callosum hypoplasia (CCH) lacked syndromic features and had consanguineous parents, suggesting recessive causes. Exome sequence analysis identified C12orf57 mutations at the initiator methionine codon in four different families. C12orf57 is ubiquitously expressed and encodes a poorly annotated 126 amino acid protein of unknown function. This protein is without significant paralogs but has been tightly conserved across evolution. Our data suggest that this conserved gene is required for development of the human corpus callosum. 相似文献
103.
Leyi Gong Xiaochun Han Tania Silva Yun-Chou Tan Bindu Goyal Parch Tivitmahaisoon Alejandra Trejo Wylie Palmer Heather Hogg Alam Jahagir Muzaffar Alam Paul Wagner Karin Stein Lubov Filonova Brad Loe Ferenc Makra David Rotstein Lubica Rapatova David Goldstein 《Bioorganic & medicinal chemistry letters》2013,23(12):3565-3569
A novel series of indole/indazole-aminopyrimidines was designed and synthesized with an aim to achieve optimal potency and selectivity for the c-Jun kinase family or JNKs. Structure guided design was used to optimize the series resulting in a significant potency improvement. The best compound (17) has IC50 of 3 nM for JNK1 and 20 nM for JNK2, with greater than 40-fold selectivity against other kinases with good physicochemical and pharmacokinetic properties. 相似文献
104.
Vincent P. Alibu Sylvie Daunes Claudius D’Silva 《Bioorganic & medicinal chemistry letters》2013,23(15):4351-4353
A series of glutathione derivatives 1–4, modified at the N,S and/or COOH sites, with in vitro antitrypanosomal activity were tested against bloodstream form Trypanosoma brucei 247 wild type and a T. b. brucei 247 strain over-expressing the multiple drug resistance protein (MRPA) by 50–100x to assess the susceptibility of these compounds to resistance by the TbMRP protein. Of the compounds tested, only compound 1 inhibited both bloodstream form T. brucei and T. bruceiMRPA, with a resistance factor of 1.4, indicating it to be an inhibitor of this protein and proteins acting in synergy with the transporter, whilst 2 & 3 and its derivatives showed reduced inhibitory activity against T. bruceiMRPA, indicating them to be substrates and susceptible to resistance. 相似文献
105.
A. C. Turchetto‐Zolet F. Pinheiro F. Salgueiro C. Palma‐Silva 《Molecular ecology》2013,22(5):1193-1213
The South American continent is composed of several biogeographical regions harbouring the highest biodiversity on the globe, encompassing five of the world's biodiversity ‘hot spots’. Nonetheless, the patterns and processes responsible for shaping its astonishing species diversity are largely unknown. Here, we present a review of current South American phylogeographical knowledge based on published articles on this topic. An appraisal of the literature reveals emerging phylogeographical patterns in the biota of South America. The striking phylogeographical divergence observed among organism lineages in South American studies is suggestive of high levels of undocumented species diversity. The interplay between Pleistocene climatic oscillations and Pliocene/Miocene orogenic events has contributed to shaping the current diversity and distribution of modern lineages in both the tropical and temperate regions of South America. Although older divergence times were observed for a range of species, most herpetofauna underwent an intraspecific lineage split much earlier than other organisms. The geographical ranges of species associated with forest habitats were reduced mainly during glacial cycles, whereas species associated with open vegetation domains have shown variable responses to climatic oscillations. The results suggest a highly complex mosaic of phylogeographical patterns in South America. We suggest future research directions to promote a better understanding of the origin and maintenance of the South American biota. 相似文献
106.
Lisa Dalla Via Aída N. García-Argáez Arianna Adami Silvia Grancara Pamela Martinis Antonio Toninello Daniela Belli Dell’Amico Luca Labella Simona Samaritani 《Bioorganic & medicinal chemistry》2013,21(22):6965-6972
A convenient synthetic route and the characterization of complexes trans-[PtCl2(L)(PPh3)] (L = Et2NH (2), (PhCH2)2NH (3), (HOCH2CH2)2NH) (4) are reported. The antiproliferative activity was evaluated on three human tumor cell lines. The investigation on the mechanism of action highlighted for the most active complex 4 the capacity to affect mitochondrial functions. In particular, both the induction of the mitochondrial permeability transition phenomenon and an aspecific membrane damage occurred, depending on concentration. 相似文献
107.
Emilay B.T. Diogo Gleiston G. Dias Bernardo L. Rodrigues Tiago T. Guimarães Wagner O. Valença Celso A. Camara Ronaldo N. de Oliveira Mauro G. da Silva Vitor F. Ferreira Yen Galdino de Paiva Marilia O.F. Goulart Rubem F.S. Menna-Barreto Solange L. de Castro Eufrânio N. da Silva Júnior 《Bioorganic & medicinal chemistry》2013,21(21):6337-6348
In our continued search for novel trypanocidal compounds, twenty-six derivatives of para- and ortho-naphthoquinones coupled to 1,2,3-triazoles were synthesized. These compounds were evaluated against the infective bloodstream form of Trypanosoma cruzi, the etiological agent of Chagas disease. Compounds 17–24, 28–30 and 36–38 are described herein for the first time. Three of these novel compounds (28–30) were found to be more potent than the standard drug benznidazole, with IC50/24 h values between 6.8 and 80.8 μM. Analysis of the toxicity to heart muscle cells led to LC50/24 h of <125, 63.1 and 281.6 μM for 28, 29 and 30, respectively. Displaying a selectivity index of 34.3, compound 30 will be further evaluated in vivo. The electrochemical properties of selected compounds were evaluated in an attempt to find correlations with trypanocidal activity, and it was observed that more electrophilic quinones were generally more potent. 相似文献
108.
Circadian rhythms in the emergence of S. mansoni cercariae from Biomphalaria tenagophila and B. glabrata, snail hosts of schistosomosis in Brazil, were investigated. A total of 35 specimens of B. tenagophila (São Paulo, Brazil) and 12 B. glabrata (Minas Gerais, Brazil) exposed individually to five miracidia of Schistosoma mansoni originated from the same biotope as their snail hosts, were tested. Observations were carried out at outdoors, with the quantification of cercarial emergence at 3h intervals during three consecutive days in November 1989 and in May 1990. Cercarial emergence was essentially diurnal (from 06.00-18.00h) in both species. Circadian rhythms were detected by the Single Cosinor Method among 74.3% of B. tenagophila and 91.7% of B. glabrata snails. The acrophases corresponding to individual snails were between 11.37 e 17.54h in B. tenagophila and between 14.15 and 16.29h in B. glabrata. These findings confirm our preliminary observations in B. tenagophila and are in accordance to those of other authors in regard to B. glabrata. The acrophases of individual snails were similar within each species, thus indicating that at populacional level cercarial emergence was concentrated in particular times of the day. Group acrophases for each species varied from 13.22 to 15.22h and were not significantly different between B. tenagophila and B. glabrata. Cercariae emerging from B. tenagophila snails seemed to be more sensitive to environmental temperature than those emerging from B. glabrata, at least in the temperature range prevailing along the tests. Further chronobiological studies on host-parasite interactions are encouraged to improve our knowledge about temporal aspects of schistosomosis transmission. 相似文献
109.
Surama F Zanini C. A. A. Torres Neura Bragagnolo Jane M Turatti Marta G Silva M. S. Zanini 《Archives of animal nutrition》2013,67(6):429-442
Three hundred and twenty 30-week old White Leghorn cockerels were housed in individual cages and distributed in a completely randomized factorial design of 5?×?3, with five oil sources (sunflower, soybean, canola, linseed and fish/soybean) and three levels of antioxidant (30, 200 and 400?mg of vitamin E/kg). The aim of this study was to evaluate the effect of the ratio of ω6?:?ω3 fatty acids by the inclusion of different oil sources and of dietary supplementation with vitamin E on the reproductive performance of cockerels. The use of the fish/soybean combination determined the lowest total antioxidant status of the semen. However, the addition of vitamin E to the fish/soybean-oil-based diet resulted in a linear increase in semen volume, motility and sperm vigour in the 38th week and again in the 52nd week for motility and for sperm vigour and fertility rate in the periods from 50?–?53 and 41?–?53 weeks of age. The use of canola oil in the diet resulted in the highest fertility rate during 50?–?53 and 41?–?53 weeks of life. Animals receiving the soybean oil based diet showed the smallest fertility rate in the range from 50?–?53 weeks of age and concomitantly the highest level of cholesterol in the spermatozoa in the range from 47?–?51 weeks. An interaction between the vitamin E level and soybean oil was verified by the linear increase in motility and sperm vigour at 38 weeks of age. Later, the contrary was shown by a linear reduction in fertility in the periods from 44?–?46, 47?–?49 and 41?–?53 weeks of age. Cockerels that had been fed on the sunflower-oil-based diet showed the highest content of saturated fatty acids in the spermatozoa from 48?–?51 weeks. An interaction effect was observed between the vitamin E level and sunflower oil shown by a linear increase in the content of saturated fatty acids in the spermatozoa and a linear reduction in the C18?:?1ω9, C18?:?2ω6 and PUFA (C18?:?2ω6?+?C20?:?4ω6) contents in the spermatozoa at 48?–?51 weeks and in sperm volume at 52 weeks of age. 相似文献
110.
Marcelo Magioli Katia Maria Paschoaletto Micchi de Barros Ferraz Eleonore Zulnara Freire Setz Alexandre Reis Percequillo Michelle Viviane de Sá Santos Rondon Vanessa Villanova Kuhnen Mariana Cristina da Silva Canhoto Karen Evelyn Almeida dos Santos Claudia Zukeran Kanda Gabriela de Lima Fregonezi Helena Alves do Prado Mitra Katherina Ferreira Milton Cezar Ribeiro Priscilla Marqui Schmidt Villela Luiz Lehmann Coutinho Márcia Gonçalves Rodrigues 《European Journal of Wildlife Research》2016,62(4):431-446