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111.
Boaretto Rodrigo M. Hippler Franz W. R. Ferreira Guilherme A. Azevedo Ricardo A. Quaggio Jose A. Mattos Dirceu 《Plant and Soil》2020,454(1-2):57-75
Plant and Soil - The aims of this study were to (i) assess how the P concentration in leaves of common Australian native plant species varies across a broad geographic region that includes... 相似文献
112.
Bruna Nunes de Luna Maria de Ftima Freitas Karla Marins Mattos da Silva Claudia Franca Barros 《Protoplasma》2020,257(3):863-870
Salt stress is harmful to plants, especially for those that live under conditions of intense salt aport. For this reason, several species present alternatives to prevent or diminish the damages that high salt concentrations may cause to the cells. Salt glands are one of these alternatives once they are specialized structures that secrete salt. Here, we aimed to investigate if the glandular trichomes in the leaves of Jacquinia armillaris are salt glands. Anatomical and ultrastructural observations showed that the glandular trichomes in J. armillaris resemble the salt glands from other recretohalophytes Primulaceae, such as, their occurrence in sunken regions in the leaf epidermis, the presence of a large basal cell that acts as a collecting cell, the detachment of the cuticle from the outer periclinal walls forming a cuticular chamber, the thickness of the cuticle in the stalk portion of the trichome, and the presence of sodium and chloride ions in the secretion and in the xylem. Altogether, the gathered results support the hypothesis that the glandular trichomes in J. armillaris are adapted to salt secretion, thus characterizing as salt glands. 相似文献
113.
Silveira PP Portella AK Benetti Cda S Zugno AI Scherer EB Mattos CB Wyse AT Lucion AB Dalmaz C 《Neurochemical research》2011,36(11):2075-2082
There is increasing evidence that early life events can influence neurodevelopment and later susceptibility to disease. Chronic
variable stress (CVS) has been used as a model of depression. The objective of this study was to evaluate the interaction
between early experience and vulnerability to chronic variable stress in adulthood, analyzing emotional, metabolic and neurochemical
aspects related to depression. Pups were (1) handled (10 min/day) or (2) left undisturbed from day 1 to 10 after birth. When
the animals reached adulthood, the groups were subdivided and the rats were submitted or not to CVS, which consisted of daily
exposure to different stressors for 40 days, followed by a period of behavioral tasks, biochemical (plasma corticosterone
and insulin sensitivity) and neurochemical (Na+,K+-ATPase activity in hippocampus, amygdala and parietal cortex) measurements. Neonatally-handled rats demonstrated shorter
immobility times in the forced swimming test, independently of the stress condition. There was no difference concerning basal
corticosterone or insulin sensitivity between the groups. Na+,K+-ATPase activity was decreased in hippocampus and increased in the amygdala of neonatally-handled rats. CVS decreased the
enzyme activity in the three structures, mainly in the non-handled group. These findings suggest that early handling increases
the ability to cope with chronic variable stress in adulthood, with animals showing less susceptibility to neurochemical features
associated with depression, confirming the relevance of the precocious environment to vulnerability to psychiatric conditions
in adulthood. 相似文献
114.
Yu Z Bekker M Tramonti A Cook GM van Ulsen P Scheffers DJ de Mattos JT De Biase D Luirink J 《Journal of bacteriology》2011,193(6):1308-1316
The function of the essential inner membrane protein (IMP) YidC in Escherichia coli has been studied for a limited number of model IMPs and primarily using targeted approaches. These studies suggested that YidC acts at the level of insertion, folding, and quality control of IMPs, both in the context of the Sec translocon and as a separate entity. To further our understanding of YidC's role in IMP biogenesis, we screened a random overexpression library for factors that rescued the growth of cells upon YidC depletion. We found that the overexpression of the GadX and GadY regulators of the glutamate-dependent acid resistance system complemented the growth defect of YidC-depleted cells. Evidence is presented that GadXY overexpression counteracts the deleterious effects of YidC depletion on at least two fronts. First, GadXY prepares the cells for the decrease in respiratory capacity upon the depletion of YidC. Most likely, GadXY-regulated processes reduce the drop in proton-motive force that impairs the fitness of YidC-depleted cells. Second, in GadXY-overproducing cells increased levels of the general chaperone GroEL cofractionate with the inner membranes, which may help to keep newly synthesized inner membrane proteins in an insertion-competent state when YidC levels are limiting. 相似文献
115.
Ferreira IM Vidal JE de Mattos Cde C de Mattos LC Qu D Su C Pereira-Chioccola VL 《Experimental parasitology》2011,129(2):190-195
This study investigated the genetic characteristics of Toxoplasma gondii samples collected from 62 patients with toxoplasmosis in Sao Paulo State, Brazil. DNA samples were isolated from blood, cerebrospinal fluid and amniotic fluids of 25 patients with cerebral toxoplasmosis and AIDS, two patients with acute toxoplasmosis, 12 patients with ocular toxoplasmosis, six newborns with congenital toxoplasmosis and 17 pregnant women with acute infection. Diagnosis of toxoplasmosis was based in clinical, radiological and laboratory features. Genotyping was performed using multilocus PCR–RFLP genetic markers including SAG1, SAG2, 5′- and 3′-SAG2, alt.SAG2, SAG3, BTUB, GRA6, C22-8, c29-2, L358, PK1 and Apico. Among the 62 clinical samples, 20 (32%) were successfully genotyped at eight or more genetic loci and were grouped to three distinct genotypes. Eighteen samples belonged to ToxoDB Genotype #65 and the other two samples were identified as ToxoDB Genotypes #6 and #71, respectively (http://toxodb.org/toxo/). Patients presenting Genotypes #6 and #71 had severe and atypical cerebral toxoplasmosis, characterized by diffuse encephalitis without extensive brain lesions. These results indicate that T. gondii Genotype #65 may have a high frequency in causing human toxoplasmosis in Sao Paulo State, Brazil. This unusual finding highlights the need to investigate the possible association of parasite genotypes with human toxoplasmosis. 相似文献
116.
de Torres EM Barbosa GA Bernardes SR de Mattos Mda G Ribeiro RF 《Journal of biomechanics》2011,44(9):1735-1739
An inappropriate prosthetic fit could cause stress over the interface implant/bone. The objective of this study was to compare stresses transmitted to implants from frameworks cast using different materials and to investigate a possible correlation between vertical misfits and these stresses. Fifteen one-piece cast frameworks simulating bars for fixed prosthesis in a model with five implants were fabricated and arranged into three different groups according to the material used for casting: CP Ti (commercially pure titanium), Co-Cr (cobalt-chromium) or Ni-Cr-Ti (nickel-chromium-titanium) alloys. Each framework was installed over the metal model with all screws tightened to a 10 N cm torque and then, vertical misfits were measured using an optical microscope. The stresses transmitted to implants were measured using quantitative photoelastic analysis in values of maximum shear stress (τ), when each framework was tightened to the photoelastic model to a 10 N cm standardized torque. Stress data were statistically analyzed using one-way ANOVA and Tukey's test and correlation tests were performed using Pearson's rank correlation (α = 0.05). Mean and standard deviation values of vertical misfit are presented for CP Ti (22.40 ± 9.05 μm), Co-Cr (66.41 ± 35.47 μm) and Ni-Cr-Ti (32.20 ± 24.47 μm). Stresses generated by Co-Cr alloy (τ = 7.70 ± 2.16 kPa) were significantly higher than those generated by CP Ti (τ = 5.86 ± 1.55 kPa, p = 0.018) and Ni-Cr-Ti alloy (τ = 5.74 ± 3.05 kPa, p = 0.011), which were similar (p = 0.982). Correlations between vertical misfits and stresses around the implants were not significant as for any evaluated materials. 相似文献
117.
Mattos AC Martins-Souza RL Kusel JR Coelho PM 《Memórias do Instituto Oswaldo Cruz》2011,106(4):424-432
The outcome of the interaction between Biomphalaria and Schistosoma mansoni depends on the response of the host internal defence system (IDS) and the escape mechanisms of the parasite. The aim of this study was to evaluate the responsiveness of the IDS (haemocytes and soluble haemolymph factors) of resistant and susceptible Biomphalaria tenagophila lineages and Biomphalaria glabrata lineages in the presence of in vitro-transformed primary sporocysts and secondary sporocysts obtained from infected B. glabrata. To do this, we assayed the cellular adhesion index (CAI), analysed viability/mortality, used fluorescent markers to evaluate the tegumental damage and transplanted secondary sporocysts. B. tenagophila Taim was more effective against primary and secondary sporocystes than the susceptible lineage and B. glabrata. Compared with secondary sporocysts exposed to B. tenagophila, primary sporocysts showed a higher CAI, a greater percentage of dead sporocysts and were labelled by lectin from Glycine max and Alexa-Fluor 488 fluorescent probes at a higher rate than the secondary sporocysts. However, the two B. tenagophila lineages showed no cercarial shedding after inoculation with secondary sporocysts. Our hypothesis that secondary sporocysts can escape the B. tenagophila IDS cannot be confirmed by the transplantation experiments. These data suggest that there are additional mechanisms involved in the lower susceptibilty of B. tenagophila to S. mansoni infection. 相似文献
118.
119.
In species of Clusia, switching from C3-photosynthesis (C3-PS)to crassulacean acid metabolism (CAM) may be a means of optimizingwater use, plant carbon balance and photon utilization duringperiods of stress. We ask whether, in perennial species of Clusia,the switch from CAM back to C3-PS is also of ecophysiologicalsignificance. Our objective was to investigate the performanceof C. minor L. during a short-term shift from CAM to C3-PS.During the transition from CAM to C3-PS, nocturnal malate andcitrate accumulation decreased whereas CO2uptake increased duringthe daytime. However, after 7 d, marked nocturnal accumulationof citrate and 24 h CO2uptake occurred. In contrast to C3-likephotosynthesis, a pronounced reduction in the effective quantumyield of photosystem II, 相似文献
120.
Over the years, many attempts have been made to develop special stethoscopes for the teaching of auscultation. The objective of this article is to report on the experience with the development and implementation of an electronic stethoscope and a virtual library of cardiac sounds. There were four stages to this project: (1) the building of the prototype to acquire, filter and amplify the cardiac sounds, (2) the development of a software program to record, reproduce and visualize them, (3) the testing of the prototype in a clinical scenario, and (4) the development of an internet site, to store and display the sounds collected. The first two stages are now complete. The prototype underwent an initial evaluation in a clinical scenario within the Unit and during virtual out-patient clinical sessions. One hundred auscultations were recorded during these tests. They were reviewed and discussed on-line by a panel of experience cardiologists during the sessions. Although the sounds were considered "satisfactory" for diagnostic purposes by the cardiology team, they identified some qualitative differences in the electronic recorded auscultations, such as a higher pitch of the recorded sounds. Prospective clinical studies are now being conducted to further evaluate the interference of the electronic device in the physicians' capability to diagnose different cardiac conditions. An internet site (www.caduceusvirtual.com.br/ auscultaped) was developed to host these cardiac auscultations. It is set as a library of cardiac sounds, catalogued by pathologies and already contains examples from auscultations of the majority of common congenital heart lesions, such as septal defects and valvar lesions. 相似文献