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11.
Malkeet Singh Bahia Shravan Kumar Gunda Shwetha Reddy Gade Saikh Mahmood Ravikumar Muttineni Om Silakari 《Journal of molecular modeling》2011,17(1):9-19
Anthranilic acid based derivatives (ANTs) have been identified as a novel class of potent tumor necrosis factor-α converting
enzyme (TACE) inhibitors. A computational strategy based on molecular docking studies, followed by CoMFA and CoMSIA analyses
has been performed to elucidate the atomic details of the TACE/ANT interactions and also to identify the most important features
impacting TACE inhibitory activity of ANTs. The CoMSIA model resulted to be slightly more predictive than CoMFA model, and
gave conventional r2 0.991, rcv2 0.793, q2 0.777, SEE 0.050, F-value 655.610, and rtest2 0.871. The 3D-QSAR field contributions and the structural features of the TACE binding site showed a good correlation. These
studies will be useful to design new TACE inhibitors with improved potency. 相似文献
12.
Aléssio FM Dantas-Torres F Siqueira DB Lizée MH Marvulo MF Martins TF Labruna MB Silva JC Mauffrey JF 《Experimental & applied acarology》2012,57(1):83-90
We investigated the Amblyomma fuscum load on a pullulating wild rodent population and the environmental and biological factors influencing the tick load on the
hosts. One hundred and three individuals of Thrichomys laurentius were caught in an Atlantic forest fragment in northeastern Brazil, as part of a longitudinal survey on ticks infesting non-volant
small mammals. Ticks (n = 342) were found on 45 individuals and the overall mean intensity of infestation was 7.6 ticks per infested rodent. Ticks
were highly aggregated in the host population and the negative binomial distribution model provides a statistically satisfactory
fit. The aggregated distribution was influenced by sex and age of the host. The microhabitat preference by T. laurentius probably increases contact opportunities between hosts and aggregated infesting stages of the ticks and represents important
clues about the habitat suitability for A. fuscum. 相似文献
13.
It has long been recognized that divalent cations modulate cell excitability. Sensory nerve excitability is of critical importance to peripheral diseases associated with pain, sensory dysfunction and evoked reflexes. Thus we have studied the role these cations play on dissociated sensory nerve activity. Withdrawal of both Mg(2+) and Ca(2+) from external solutions activates over 90% of dissociated mouse sensory neurons. Imaging studies demonstrate a Na(+) influx that then causes depolarization-mediated activation of voltage-gated Ca(2+) channels (Ca(V)), which allows Ca(2+) influx upon divalent re-introduction. Inhibition of Ca(V) (ω-conotoxin, nifedipine) or Na(V) (tetrodotoxin, lidocaine) fails to reduce the Na(+) influx. The Ca(2+) influx is inhibited by Ca(V) inhibitors but not by TRPM7 inhibition (spermine) or store-operated channel inhibition (SKF96365). Withdrawal of either Mg(2+) or Ca(2+) alone fails to evoke cation influxes in vagal sensory neurons. In electrophysiological studies of dissociated mouse vagal sensory neurons, withdrawal of both Mg(2+) and Ca(2+) from external solutions evokes a large slowly-inactivating voltage-gated current (I(DF)) that cannot be accounted for by an increased negative surface potential. Withdrawal of Ca(2+) alone fails to evoke I(DF). Evidence suggests I(DF) is a non-selective cation current. The I(DF) is not reduced by inhibition of Na(V) (lidocaine, riluzole), Ca(V) (cilnidipine, nifedipine), K(V) (tetraethylammonium, 4-aminopyridine) or TRPM7 channels (spermine). In summary, sensory neurons express a novel voltage-gated cation channel that is inhibited by external Ca(2+) (IC(50)~0.5 μM) or Mg(2+) (IC(50)~3 μM). Activation of this putative channel evokes substantial cation fluxes in sensory neurons. 相似文献
14.
Francesca Rossi Antonio Giorgio Marco Battaglini Maria Laura Stromillo Emilio Portaccio Benedetta Goretti Antonio Federico Bahia Hakiki Maria Pia Amato Nicola De Stefano 《PloS one》2012,7(11)
Objective
To assess the relationship between cognition and brain white matter (WM) lesion distribution and frequency in patients with relapsing-remitting multiple sclerosis (RR MS).Methods
MRI-based T2 lesion probability map (LPM) was used to assess the relevance of brain lesion location for cognitive impairment in a group of 142 consecutive patients with RRMS. Significance of voxelwise analyses was p<0.05, cluster-corrected for multiple comparisons. The Rao Brief Repeatable Battery was administered at the time of brain MRI to categorize the MS population into cognitively preserved (CP) and cognitively impaired (CI).Results
Out of 142 RRMS, 106 were classified as CP and 36 as CI. Although the CI group had greater WM lesion volume than the CP group (p = 0.001), T2 lesions tended to be less widespread across the WM. The peak of lesion frequency was almost twice higher in CI (61% in the forceps major) than in CP patients (37% in the posterior corona radiata). The voxelwise analysis confirmed that lesion frequency was higher in CI than in CP patients with significant bilateral clusters in the forceps major and in the splenium of the corpus callosum (p<0.05, corrected). Low scores of the Symbol Digit Modalities Test correlated with higher lesion frequency in these WM regions.Conclusions
Overall these results suggest that in MS patients, areas relevant for cognition lie mostly in the commissural fiber tracts. This supports the notion of a functional (multiple) disconnection between grey matter structures, secondary to damage located in specific WM areas, as one of the most important mechanisms leading to cognitive impairment in MS. 相似文献15.
Dos Santos FM Caldas S de Assis Cáu SB Crepalde GP de Lana M Machado-Coelho GL Veloso VM Bahia MT 《Experimental parasitology》2008,120(4):385-390
Through a continuous in vivo drug pressure protocol, using mice as experimental model, we induced benznidazole resistance in Trypanosoma cruzi stocks. Full resistance was obtained for four out of five T. cruzi stocks analyzed. However, the number of benznidazole doses (40–180), as well as the time (4–18 months) necessary to induce resistance varied among the different T. cruzi stocks. The resistance phenotype remained stable after T. cruzi stocks has been maintained by 12 passages in mice (six months) and in acellular culture for the same time. However, the maintenance of resistant parasite for 12 months in acellular culture induces a reduction in its level of benznidazole resistance, while no alteration was detected in parasite maintained for the same time in mice. The data showed the stability of the resistance acquired by drug pressure, but suggest the possibility of reversible changes in the resistance levels after maintenance for long time in acellular culture. 相似文献
16.
Zahr-Eddine Djazouli Bahia Doumandji-Mitiche Daniel Petit 《Comptes rendus biologies》2009,332(9):848-860
This study presents the first data describing the communities of insects and arachnida colonizing 4 aerial compartments of Populus nigra. In terms of temporal variation and total abundance, the analyses show that the communities are structurally and functionally different. It also appears that the taxonomic richness of the communities, and partly their temporal distribution, change according to the gradient of the energy and defense resources under the effect of seasonal variations. The highest species richness recorded on the leaves compartment is due to the amplitude of histo-physiological modifications observed throughout the growing season. To cite this article: Z.-E. Djazouli et al., C. R. Biologies 332 (2009). 相似文献
17.
Polyclad flatworms have a troubled classification history, with two contradicting systems in use. They both rely on a ventral adhesive structure to define the suborders Acotylea and Cotylea, but superfamilies were defined according to eyespot arrangement (Prudhoe’s system) or prostatic vesicle characters (Faubel’s system). Molecular data available cover a very limited part of the known polyclad family diversity and have not allowed testing morphology-based classification systems on Polycladida yet. We thus sampled a suitable marker, partial 28S ribosomal DNA (rDNA), from Polycladida (19 families and 32 genera), generating 136 new sequences and the first comprehensive genetic dataset on polyclads. Our maximum likelihood (ML) analyses recovered Polycladida, but the traditional suborders were not monophyletic, as the supposedly acotyleans Cestoplana and Theama were nested within Cotylea; we suggest that these genera should be included in Cotylea. The partial 28S rDNA trees were generally well supported and robust but in conflict with both Faubel’s and Prudhoe’s superfamilies. Therefore, we compiled morphological and anatomical characters for all taxa used and examined their distribution on our molecular tree. Combining morphological and molecular evidence, we redefined polyclad superfamilies. Acotylea contain tentaculated and atentaculated groups and is now divided in three superfamilies. The suborder Cotylea can be divided in five superfamilies. In general, there is a trait of anteriorization of sensory structures, from the plesiomorphic acotylean body plan to the cotylean gross morphology. Traditionally used characters, such as prostatic vesicle, eyespot distribution, and type of pharynx, are all homoplastic and likely have misled polyclad systematics so far. 相似文献
18.
Fernanda Aparecida Nieri-Bastos Marcos Gomes Lopes Paulo Henrique Duarte Can?ado Giselle Ayres Razera Rossa Jo?o Luiz Horácio Faccini Solange Maria Gennari Marcelo Bahia Labruna 《Memórias do Instituto Oswaldo Cruz》2014,109(2):259-261
Adult ticks of the species Amblyomma parvum were collected from the
vegetation in the Pantanal biome (state of Mato Grosso do Sul) and from horses in the
Cerrado biome (state of Piauí) in Brazil. The ticks were
individually tested for rickettsial infection via polymerase chain reaction (PCR)
targeting three rickettsial genes, gltA, ompA and
ompB. Overall, 63.5% (40/63) and 66.7% (2/3) of A.
parvum ticks from Pantanal and Cerrado, respectively, contained
rickettsial DNA, which were all confirmed by DNA sequencing to be 100% identical to
the corresponding fragments of the gltA, ompA and
ompB genes of Candidatus Rickettsia andeanae.
This report is the first to describe Ca. R. andeanae in Brazil. 相似文献
19.
20.
Vanessa Moura dos Reis Cláudia Santiago Karez Rodrigo Mariath Fernando Coreixas de Moraes Rodrigo Tomazetto de Carvalho Poliana Silva Brasileiro Ricardo da Gama Bahia Tito Monteiro da Cruz Lotufo Laís Vieira Ramalho Rodrigo Le?o de Moura Ronaldo Bastos Francini-Filho Guilherme Henrique Pereira-Filho Fabiano Lopes Thompson Alex Cardoso Bastos Leonardo Tavares Salgado Gilberto Menezes Amado-Filho 《PloS one》2016,11(4)
The abundance of reef builders, non-builders and the calcium carbonate produced by communities established in Calcification Accretion Units (CAUs) were determined in three Abrolhos Bank shallow reefs during the period from 2012 to 2014. In addition, the seawater temperature, the irradiance, and the amount and composition of the sediments were determined. The inner and outer reef arcs were compared. CAUs located on the inner reef shelf were under the influence of terrigenous sediments. On the outer reefs, the sediments were composed primarily of marine biogenic carbonates. The mean carbonate production in shallow reefs of Abrolhos was 579 ± 98 g m-2 y-1. The builder community was dominated by crustose coralline algae, while the non-builder community was dominated by turf. A marine heat wave was detected during the summer of 2013–2014, and the number of consecutive days with a temperature above or below the summer mean was positively correlated with the turf cover increase. The mean carbonate production of the shallow reefs of Abrolhos Bank was greater than the estimated carbonate production measured for artificial structures on several other shallow reefs of the world. The calcimass was higher than the non-calcareous mass, suggesting that the Abrolhos reefs are still in a positive carbonate production balance. Given that marine heat waves produce an increase of turf cover on the shallow reefs of the Abrolhos, a decrease in the cover represented by reef builders and shifting carbonate production are expected in the near future. 相似文献