12 resultados para nature of performance
em Scielo Saúde Pública - SP
Resumo:
This paper discusses the relations between the genera Toddia and Pirhemocyton, describing certain cytochemical reactions that clarify their nature, and discussing the position of these organisms as being of a parasitic or viral nature. A new species of Pirhemocyton is described form Iguana iguana from Mamo, Marapa (Dto. Federal) of Venezuela; characterized by rectangular globoids with rounded borders. Attempts at experimental infections of other genera of lizerds indicate that the new species, Pirhemocyton iguanae, is specific to the natural host, Iguana iguana. The course of the parasitemia in the lizard is described.
Resumo:
Toddia França, 1912 under the light microscope occurs as inclusion corpuscles in the cytoplasm of erythrocytes of cold-blooded vertebrates sometimes accompanied by crystalloid bodies. Its position among the protozoans or the viruses has been discussed by some authors, but remained unclear. To elucidate this problem we studied Toddia from a Brazilian frog (Leptodactylus ocellatus) by electron microscopy. In the cytoplasm of the infected cells we found no protozoan, but rather virus-like particles often hexagonal in outline, averaging 195 nm excluding their two involving membranes, and presenting a central area of variable electron density. Particles at different stages of development were generally found around or on area lighter density than the cytoplasm. which resembled a virus synthesis site. At high magnification, the nuclear or cytoplasmic crystals allied to Toddia resembled the crystalline lattice of the inclusion bodies associated with the polyhedrosis viruses and poxviruses from insects, of the capsules of granulosis viruses and of other protein crystals in ultrathin sections. Cytochemical tests in Toddia corpuscles displayed exclusively the presence of deoxyribonucleic acid. These findings indicate that Toddia is not a protozoan and demonstrate that it is in all probability a viral inclusion corpuscle. Taking into account the nucleic acid type found in its structure (DNA) and the hexagonal shape usually shown in ultrathin sections by its component particles, which have a cytoplasmic site of synthesis and assembly, we tentatively relate Toddia with the so-called "Icosahedral Cytoplasmic Deoxyriboviruses". We believe that the present paper gives the first report of virus-like particles in L. ocellatus.
Resumo:
1. Autoimmunity in deisease is driven by autoantigen; 2. Cell surface molecules may stimulate autoreactive T-helpers if call II MHC is expressed; special factors may predispose to the ease of class II induction; 3. Soluble autoantigens may be focussed by primed B-cells and processed for presentation to T-cell; 4. autoantigenicity may be influenced by metabolic events: (a) Poorly iodinated thyroglobulin does not induce thyroiditis; (b) IgG rheumatoid arthritis has galactose deficient Fc oligosaccharides. Glycosylation defects may prove to have wide implications.
Resumo:
The aim of this work was to evaluate the humus composition from an Ultisol from Campos dos Goytacazes, RJ, Brazil. Soil samples of four depths (0-0.05, 0.05-0.10, 0.10-0.20 and 0.20-0.40 m) and its chemical nature were analysed by elemental composition, E4/E6 ratios and Fourier transformed infrared spectroscopy. The bioactivity of these humified substances was evaluated through their action on maize root growth and H+-ATPase activity of roots microsomes. In topsoil, the content of high condensed alkaline soluble humic substances is greater than that found in the subsuperficial layers. The chemical nature of humic and fulvic acids also varied with the soil depth. The humic acids isolated from the soil samples exhibited higher bioactivity compared with the fulvic acids. Moreover, the results suggest that more condensed humic substances can promote highest stimulation of the microsomal H+-ATPases from maize roots. These data reinforce the concept that the activity of the H+ pumps can be used as a biochemical marker for evaluation of humic substances bioactivity.
Resumo:
ABSTRACT The objective of this article is to contribute to the understanding of Nāgārjuna's 'two truths' doctrine (satyadvaya) as presented in the Mūlamadhyamakakārikā ("The Fundamental Verses of the Middle Path") (XXIV.8-10). For that purpose, we argue that 'two truths' doctrine the basic structural framework for the operational functionality of upāya of upāya (lit., 'skilful means'), perhaps the most important epistemological/pedagogical notion of Mahāyāna Buddhism.
Resumo:
Over the last decades, the emphasis on the health of dairy cows has changed from an individual to a herd level. In this scenario, the role played by the recording system and its interpretation by veterinarians has gained primordial importance. The records of productive and reproductive performance and of sanitary status from a southern Brazilian dairy cattle herd have been presented and discussed. The period of study was 2000-2009. Mean values per lactation period were 349D 8436M 290F 275P 201SCS (D: days in lactation, M: kg of milk yield, F: kg of fat, P: kg of protein and SCS: somatic cell score in 1000 cells/ml of milk). Major indexes of reproductive efficiency included age at first calving (31 months), services per conception (2.1), intercalving interval (428 days), calving to conception interval (146 days), mean annual rates of parturitions (76.2%), fetal losses (9.8-19.0%), and stillbirths (3.6%), apart of voluntary waiting period (94 days). Main information on sanitary status of the herd was associated with the mean prevalence of common disorders of dairy cattle such as anaplasmosis (29.8%), mastitis (27.8%), digital diseases (26.3%), ovarian cysts (21.3%), placental retention (19.7%), postpartum uterine infections (10.6%), and calf diarrhea (23.7%) and pneumonia (16.8%), among others. In addition, culling reasons (low reproductive performance [56.3%] and udder/mastitis problems [33.6%]), causes of cattle deaths (anaplasmosis [16.4%] and leukosis [11.4]), and the impact of cattle diseases such as tuberculosis, leukosis, and neosporosis on the herd have also been presented and succinctly discussed. Numbers between brackets represent rates accumulated in the 10-year period.
Resumo:
Pilocarpine-induced (320 mg/kg, ip) status epilepticus (SE) in adult (2-3 months) male Wistar rats results in extensive neuronal damage in limbic structures. Here we investigated whether the induction of a second SE (N = 6) would generate damage and cell loss similar to that seen after a first SE (N = 9). Counts of silver-stained (indicative of cell damage) cells, using the Gallyas argyrophil III method, revealed a markedly lower neuronal injury in animals submitted to re-induction of SE compared to rats exposed to a single episode of pilocarpine-induced SE. This effect could be explained as follows: 1) the first SE removes the vulnerable cells, leaving behind resistant cells that are not affected by the second SE; 2) the first SE confers increased resistance to the remaining cells, analogous to the process of ischemic tolerance. Counting of Nissl-stained cells was performed to differentiate between these alternative mechanisms. Our data indicate that different neuronal populations react differently to SE induction. For some brain areas most, if not all, of the vulnerable cells are lost after an initial insult leaving only relatively resistant cells and little space for further damage or cell loss. For some other brain areas, in contrast, our data support the hypothesis that surviving cells might be modified by the initial insult which would confer a sort of excitotoxic tolerance. As a consequence of both mechanisms, subsequent insults after an initial insult result in very little damage regardless of their intensity.
Resumo:
ABSTRACT The paper discusses the dynamics of capital accumulation in Latin America economies. The hypothesis is that in these economies the role of the State is comparatively broader than in the economies of the centers of the capitalism by structural reasons. The argument is mainly based on Marx and Kalecki, besides historical elements of Latin America economies, particularly the Brazilian economy. Then the paper explores the dynamics consequences of this nature at the national levels, concluding that this condition gives a higher degree of instability.
Resumo:
Human rights do not represent an absolute truth. Otherwise, they would represent ideology, which is contradictory to the basic idea of human rights itself. Consequently, there is a need for redefinition of the main presuppositions of modern conception of human rights represented in the Universal Declaration of Human Rights. This paper argues that Rawls's conception of human rights is significant for the refiguration of human rights. It represents the path towards postmodern idea of human rights and the recognition of difference.
Resumo:
The objective of the present study was to evaluate the anticoccidial effect of the different concentrations of the acetic acid in the broiler chickens in comparison with the amprolium anticoccidial. A total of 198 chicks were placed 11 per pen with three pens per treatment. The different concentrations (1%, 2% and 3%) of acetic acid and amproilum (at the dose rate of 125ppm) were given to the experimental groups in drinking water from 10-19th days of age. One group was kept as infected non medicated control and one as non infected non medicated control. All the groups were inoculated orally with 75,000 sporulated oocysts at the 12th day of age except non infected non medicated control. Anticoccidial effect was evaluated on the basis of performance (weight gain, feed conversion ratio) and pathogenic (oocyst score, lesion score and mortality %age) parameters. Among acetic acid medicated groups, the maximum anticoccidial effect was seen in the group medicated with 3% acetic acid followed by 2% and 1% acetic acid medicated groups. Amprolium and 3% acetic acid were almost equivalent in suppressing the negative performance and pathogenic effects associated with coccidiosis (Eimeria tenella) challenge. In summary, acetic acid has the potential to be used as alternative to chemotherapeutic drugs for Eimeria tenella control. Concentration-dependent anticoccidial effect of acetic acid suggests that further studies should be carried out to determine the possible maximum safe levels of acetic acid with least toxic effects to be used as anticoccidial.
Resumo:
The role of chloride in the stabilization of the deoxy conformation of hemoglobin (Hb), the low oxygen affinity state, has been studied in order to identify the nature of this binding. Previous studies have shown that arginines 141α could be involved in the binding of this ion to the protein. Thus, des-Arg Hb, human hemoglobin modified by removal of the α-chain C-terminal residue Arg141α, is a possible model for studies of these interactions. The loss of Arg141α and all the salt bridges in which it participates is associated with subtle structural perturbations of the α-chains, which include an increase in the conformational flexibility and further shift to the oxy state, increasing oxygen affinity. Thus, this Hb has been the target of many studies of structural and functional behavior along with medical applications. In the present study, we describe the biochemical characterization of des-Arg Hb by electrophoresis, high-performance liquid chromatography and mass spectroscopy. The effects of chloride binding on the oxygen affinity and on the cooperativity to des-Arg Hb and to native human hemoglobin, HbA, were measured and compared. We confirm that des-Arg Hb presents high oxygen affinity and low cooperativity in the presence of bound chloride and show that the binding of chloride to des-Arg does not change its functional characteristics as observed with HbA. These results indicate that Arg141α may be involved in the chloride effect on Hb oxygenation. Moreover, they show that these residues contribute to lower Hb oxygen affinity to a level compatible with its biological function.