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71.
Martins RH Gonçalves TM Neves DS Fracalossi TA Tavares EL Moretti-Ferreira D 《Genetics and molecular research : GMR》2011,10(4):3163-3168
We found evidence of autosomal dominant hereditary transmission of sulcus vocalis. Four dysphonic patients from three generations of the same family were submitted to videolaryngoscopic examination (three patients) and to direct laryngoscopy (one patient) to diagnose the hoarseness. Sulcus vocalis was diagnosed in all four patients. The finding of four affected individuals in three generations, with vertical transmission affecting man and women, is more consistent with autosomal dominant inheritance pattern; it is an etiological model that we propose for the sulcus vocalis in this pedigree. 相似文献
72.
Cassado Ados A de Albuquerque JA Sardinha LR Buzzo Cde L Faustino L Nascimento R Ghosn EE Lima MR Alvarez JM Bortoluci KR 《PloS one》2011,6(7):e22141
The peritoneal cavity (PerC) is a singular compartment where many cell populations reside and interact. Despite the widely adopted experimental approach of intraperitoneal (i.p.) inoculation, little is known about the behavior of the different cell populations within the PerC. To evaluate the dynamics of peritoneal macrophage (MØ) subsets, namely small peritoneal MØ (SPM) and large peritoneal MØ (LPM), in response to infectious stimuli, C57BL/6 mice were injected i.p. with zymosan or Trypanosoma cruzi. These conditions resulted in the marked modification of the PerC myelo-monocytic compartment characterized by the disappearance of LPM and the accumulation of SPM and monocytes. In parallel, adherent cells isolated from stimulated PerC displayed reduced staining for β-galactosidase, a biomarker for senescence. Further, the adherent cells showed increased nitric oxide (NO) and higher frequency of IL-12-producing cells in response to subsequent LPS and IFN-γ stimulation. Among myelo-monocytic cells, SPM rather than LPM or monocytes, appear to be the central effectors of the activated PerC; they display higher phagocytic activity and are the main source of IL-12. Thus, our data provide a first demonstration of the consequences of the dynamics between peritoneal MØ subpopulations by showing that substitution of LPM by a robust SPM and monocytes in response to infectious stimuli greatly improves PerC effector activity. 相似文献
73.
Boström M Tavares FW Finet S Skouri-Panet F Tardieu A Ninham BW 《Biophysical chemistry》2005,117(3):217-224
The relative effectiveness of different anions in crystallizing proteins follows a reversed Hofmeister sequence for pHpI. The phenomenon has been known almost since Hofmeister's original work but it has not been understood. It is here given a theoretical explanation. Classical electrolyte and double layer theory deals only with electrostatic forces acting between ions and proteins. Hydration and hydration interactions are dealt with usually only in terms of assumed hard core models. But there are, at and above biological salt concentrations, other non-electrostatic (NES) ion-specific forces acting that are ignored in such modeling. Such electrodynamic fluctuation forces are also responsible for ion-specific hydration. These missing forces are variously comprehended under familiar but generally unquantified terms, typically, hydration, hydrogen bonding, pi-electron-cation interactions, dipole-dipole, dipole-induced dipole and induced dipole-induced dipole forces and so on. The many important body electrodynamic fluctuation force contributions are accessible from extensions of Lifshitz theory from which, with relevant dielectric susceptibility data on solutions as a function of frequency, the forces can be extracted quantitatively, at least in principle. The classical theories of colloid science that miss such contributions do not account for a whole variety of ion-specific phenomena. Numerical results that include these non-electrostatic forces are given here for model calculations of the force between two model charge-regulated hen-egg-white protein surfaces. The surfaces are chosen to carry the same charge groups and charge density as the protein. What emerges is that for pHpI (where anions are co-ions) the forces increase in the order NaCl相似文献
74.
Tavares FX Deaton DN Miller AB Miller LR Wright LL 《Bioorganic & medicinal chemistry letters》2005,15(17):3891-3895
Ketoheterocyclic inhibitors of cathepsin K have been disclosed. SAR of potency enhancing P2-P3 groups coupled with ketoheterocyclic warheads to provide cathepsin K inhibitors have been described. In addition, a novel route to access alpha-ketothiazoles using a key thioamide functionality has been disclosed. The mild method employed allows for the presence of diverse functional groups, such as amide and carbamate functionalities, commonly found in protease inhibitors that have peptidomimetic scaffolds. This new method should provide a quick entry into functionally diverse protease inhibitors. 相似文献
75.
Genetic diversity of Histoplasma capsulatum strains in Brazil 总被引:1,自引:0,他引:1
Zancopé-Oliveira RM Morais e Silva Tavares P Muniz MM 《FEMS immunology and medical microbiology》2005,45(3):443-449
This study establishes the genetic relatedness among Brazilian Histoplasma capsulatum samples obtained from different sources. A PCR-based random amplified polymorphic DNA (RAPD) assay was used to delineate polymorphisms among isolates in geographically diverse regions in Brazil. RAPD fingerprints revealed distinct DNA profiles and provided a high level of discrimination among H. capsulatum strains from different locations. Cluster I was composed of H. capsulatum isolates from the northeast region. The majority of strains from southeast and south were categorized as major cluster II. The strain 84564 from Rio de Janeiro State showed no genetic correlation to any of the isolates from the same state. The RAPD patterns of H. capsulatum isolates from Goias (Cluster III) were unrelated to DNA fingerprints observed among the other H. capsulatum strains (48% similarity). This study is the first report that stratifies the clusters of H. capsulatum strains from Brazil by molecular typing and associates them with the geographical origin. 相似文献
76.
Tavares J Ouaissi A Lin PK Tomás A Cordeiro-da-Silva A 《International journal for parasitology》2005,35(6):637-646
The natural polyamines are ubiquitous polycationic compounds that play important biological functions in cell growth and differentiation. In the case of protozoan species that are causative agents of important human diseases such as Leishmaniasis, an exogenous supply of polyamines supports parasite proliferation. In the present study, we have investigated the effect of three polyamine derivatives, (namely bis-naphthalimidopropyl putrescine (BNIPPut), spermidine (BNIPSpd) and spermine (BNIPSpm)), on the proliferative stages of Leishmania infantum, the causative agent of visceral leishmaniasis in the Mediterranean basin. A significant reduction of promastigotes and axenic amastigotes growth was observed in the presence of increasing concentrations of the drugs, although the mechanisms leading to the parasite growth arrest seems to be different. Indeed, by using a number of biochemical approaches to analyse the alterations that occurred during early stages of parasite-drug interaction (i.e. membrane phosphatidylserine exposure measured by annexin V binding, DNA fragmentation, deoxynucleotidyltranferase-mediated dUTP end labelin (TUNEL), mitochondrial transmembrane potential loss), we showed that the drugs had the capacity to induce the death of promastigotes by a mechanism that shares many features with metazoan apoptosis. Surprisingly, the amastigotes did not behave in a similar way to promastigotes. The drug inhibitory effect on amastigotes growth and the absence of propidium iodide labelling may suggest that the compounds are acting as cytostatic substances. Although, the mechanisms of action of these compounds have yet to be elucidated, the above data show for the first time that polyamine derivatives may act differentially on the Leishmania parasite stages. Further chemical modifications are needed to make the polyamine derivatives as well as other analogues able to target the amastigote stage of the parasite. 相似文献
77.
Paulo Silva Arnoldo R. Façanha Rui M. Tavares Hernâni Gerós 《Journal of Plant Growth Regulation》2010,29(1):23-34
Populus euphratica has been used as a plant model to study resistance against salt and osmotic stresses, with recent studies having characterized
the tonoplast and the plasma membrane ATPases, and two Na+/H+ antiporters, homologs of the Arabidopsis tonoplast AtNHX1, were published in databases. In the present work we show that P. euphratica suspension-cultured cells are highly tolerant to high salinity, being able to grow with up to 150 mM NaCl in the culture
medium without substantial modification of the final population size when compared to the control cells in the absence of
salt. At a salt concentration of 300 mM, cells were unable to grow but remained highly viable up to 17 days after subculture.
The addition of a 1-M-NaCl pulse to unadapted cells did not promote a significant loss in cell viability within 48 h. In tonoplast
vesicles purified from cells cultivated in the absence of salt and from salt-stressed cells, vacuolar H+-pyrophosphatase (V-H+-PPase) seemed to be the primary tonoplast proton pump; however, there appears to be a decrease in V-H+-PPase activity with exposure to NaCl, in contrast to the sodium-induced increase in the activity of vacuolar H+-ATPase (V-H+-ATPase). Despite reports that in P. euphratica there is no significant difference in the concentration of Na+ in the different cell compartments under NaCl stress, in the present study, confocal and epifluorescence microscopic observations
using a Na+-sensitive probe showed that suspension-cultured cells subject to a salt pulse accumulated Na+ in the vacuole when compared with control cells. Concordantly, a tonoplast Na+/H+ exchange system is described whose activity is upregulated by salt and, indirectly, by a salt-mediated increase of V-H+-ATPase activity. 相似文献
78.
Recent studies have suggested that leptin hormone may play a pivotal role on bone remodeling through a direct effect by modulating positively the OPG/RANKL balance. Here, we investigate the effect of leptin hormone on RANKL and OPG expression in MC3T3-E1 osteoblasts using RT-PCR and ELISA measurements. We have at first identified the expression of Ob-Rb and Ob-Ra leptin receptor isoforms in MC3T3-E1 and observed that these cells respond to mrleptin treatments. We then investigated the effect of mrleptin on RANKL and OPG expression. We show that mrleptin dose-dependently regulated the expression of RANKL mRNA with complete inhibition observed at concentrations higher than 12 ng/ml. This effect was confirmed with sRANKL protein measurements. However, the exposure of MC3T3-E1 to mrleptin had no effect on OPG mRNA. Taken together, these results suggest that leptin modulates positively OPG/RANKL balance by inhibiting the expression of RANKL gene. 相似文献
79.
Víctor M. Jiménez Jhamna Castillo Elena Tavares Eric Guevara Mayra Montiel 《Plant Cell, Tissue and Organ Culture》2006,86(3):389-395
Guadua angustifolia Kunth was successfully propagated in vitro from axillary buds. Culture initiation, bud sprouting, shoot and plant multiplication, rooting and acclimatization, were evaluated. Best results were obtained using explants from greenhouse-cultivated plants, following a disinfection procedure that comprised the sequential use of an alkaline detergent, a mixture of the fungicide Benomyl and the bactericide Agri-mycin, followed by immersion in sodium hypochlorite (1.5% w/v) for 10 min, and culturing on Murashige and Skoog medium containing 2 ml l?1 of Plant Preservative Mixture®. Highest bud sprouting in original explants was observed when 3 mg l?1 N6-benzylaminopurine (BAP) was incorporated into the culture medium. Production of lateral shoots in in vitro growing plants increased with BAP concentration in culture medium, up to 5 mg l?1, the highest concentration assessed. After six subcultures, clumps of 8–12 axes were obtained, and their division in groups of 3–5 axes allowed multiplication of the plants. Rooting occurred in vitro spontaneously in 100% of the explants that produced lateral shoots. Successful acclimatization of well-rooted clumps of 5–6 axes was achieved in the greenhouse under mist watering in a mixture of soil, sand and rice hulls (1:1:1). 相似文献
80.