The appropriate management of acute viral encephalitis is a challenge. Clinical picture includes general symptoms and a wide range of neurological signs. Etiological diagnosis cannot be performed only by clinical means and depends on neuroimaging studies and cerebrospinal fluid molecular analyses. It is recommended since some of these viruses are treatable and that the prognoses of these infections depend on the prompt administration of antiviral and/or immunomodulatory drugs. The management of acute viral encephalitis in Brazil has some peculiarities. First, the etiological distribution of the viral encephalitis may differ from what is found in other countries. Some viruses, such as dengue virus, are more common in Brazil than in developed countries while others, like West Nile virus, are not found here. Second, there are some regions in Brazil where neuroimaging and laboratorial methods are not available, and a clinical-based decision is the only therapeutic approach. As most of the guidelines in the literature are based on complimentary methods, it is relevant to establish an alternative approach compatible with the Brazilian health system reality. The goal of this study was to review the recent advances in the field of the acute viral encephalitis, to discuss the diagnosis and the treatment of the main etiologies of acute viral encephalitis found in Brazil, and to propose a viable guideline for the evaluation of the suspected acute viral encephalitis cases in the emergence room in Brazil.
Tuberculosis and intestinal parasites affect primarily low social and economic level populations, living clustered in precarious habitational settings. One of the interesting aspects of this interaction is the parasitism influence in cellular response to tuberculosis. In the present study, we evaluated the prevalence of enteroparasitosis in tuberculosis patients, HIV-infected and non HIV infected, and we observed the influence of helminth presence in the response to tuberculin skin test (TST) and tuberculosis clinical outcomes. From 607 clinical records reviewed, 327 individuals met the study inclusion criteria and did not present any exclusion criteria. The prevalence of enteroparasites observed was 19.6%. There was no significant association among TST result and the variables related to the presence of: helminthes, protozoa, and stool test for parasites result (p>0.5). Considering the survival of this cohort, we may observe that there is no significant difference (p>0.05) between the survival curves of parasited and non parasited individuals. Solely the variable "eosinophils" presents a statistically significant association (p<0.001) with helminthes, all other associations are considered not significant. Our findings neither show an association between helminthic infection and a favorable tuberculosis outcome, nor between parasitism and TST response, unlike other in vitro studies. Apparently, experimental data do not correspond to the clinical findings.
Bean (Phaseolus vulgaris) lines P.I. 207262 and AB 136, both resistant to delta and kappa races of Colletotrichum lindemuthianum, were crossed with Michelite, Dark Red Kidney, and Perry Marrow, susceptible to both races, and with Cornell 49-242, resistant to delta and susceptible to kappa. F1 and F2 reactions demonstrated that P.I. 207262 carries duplicate dominant genes for resistance to the delta race; AB 136 carries a dominant gene. These resistance genes are independent of the Are gene from Cornell 49-242. With respect to the kappa race, F1 and F2 data showed that the resistance controlled by P.I. 207262 and by AB 136 depends on a single dominant gene. Complementary factors were involved with AB 136 resistance to the delta race and with P.I. 207262 resistance to kappa.
Variation in salt tolerance of six natural populations of Stylosanthes humilis from three ecogeographic regions, Mata (wet tropical climate), Agreste and Sertão (semi-arid tropical climate) of Pernambuco State, Northeast Brazil, was evaluated on germination in 201 mM NaCl. There were significant differences among families of all populations for germination percentage and of five populations (except Tamandaré, from Mata) for germination rate. Populations from semi-arid regions presented high coefficients of genetic variation, those from Agreste being higher than those from Sertão. Populations from Mata showed low coefficients of genetic variation. The coefficients of genotypic determination were high for five populations, except Tamandaré, both for germination percentage ( > or = 0.89) and for germination rate ( > or = 0.79), indicating the possibility of selection for salt tolerance in these populations. An electrophoretic analysis of esterase and peroxidase isozymes was also performed in the six populations, and correlations were estimated between salt tolerance and allelic frequencies. The analysis of salt tolerant and salt sensitive families of populations from Agreste suggested an association of alleles of a peroxidase locus with salt tolerance during germination in the Caruaru population
Combined therapy with radiation and chemotherapy has being increasingly used in cancer treatment. The effect of combinations of taxol (0.08 mug/ml) with doxorubicin (DXR, 0.5 or 1.0 mug/ml) or gamma radiation (20 or 40 cGy) was examined in two different treatment schedules (pretreatment or simultaneous treatment) using Chinese hamster ovary (CHO) cells treated at the G2 phase of the cell cycle. The results showed that taxol did not have a radiosensitizing effect on the chromosomal aberrations induced by gamma radiation nor did it have a potentiating effect on the chromosomal aberrations induced by DXR in CHO cells treated in the G2 phase of the cell cycle
The present study describes the production of stocks segregating dwarf (dw), bantam (dwB) and normal (dw+) alleles, as well as the characters, shank length, adult body weight, age at sexual maturity and egg production. Heterozygous K dw+/k dwB sires were mated to normal (dw+) dams to produce stock D6.a, and mated to dwB females to produce stock D6.b. Stock D4.a came from mating F1 heterozygous dwB dw sires to dwarf Leghorns. In a third series of matings, 7/8 Sebright and 1/8 dw-Leghorn dwB dw sires were crossed to three groups of dams of different genotypes. The progeny of the normal (dw+), dwarf (dw), and bantam (dwB) dams were designated as stocks D4.b, D4.c and D4.d, respectively. The dw+ dams were White Leghorn strain cross females. The difference between the rate of laying of normal (69.7%) and their bantam sisters (68.6%) was not statistically significant when the average 32-week body weight of the dw+ sisters was 1,897 g. However, when the 32-week body weight of the normal daughters from the same sires and smaller dams was around 1,646 g, the difference between the rate of laying of the normal (78.1%) and their bantam sisters (75.9%) was significant (P < 0.05). The dwB gene may have a similar but smaller effect on the rate of egg laying than its dwarf allele. The difference between sexual maturity of normal and bantam daughters of either the largest or the smallest dams was not statistically significant, even though the smallest dwB pullets were in average 2.9 days older at first egg. The use of shank length combined with adult body weight allowed a precise discrimination between bantams and dwarfs
Exact correlation coefficients between a canonical variate and measured traits were derived to evaluate genetic divergence among varieties. This method allows the plant breeder to determine which traits contribute significantly to genetic divergence and, also, to identify the most important among them. An example is presented, related to a trial where 28 varieties of maize were evaluated for two traits
Both periodic acid and photographic reagents have been used to remove the silver nitrate residues from cytological preparations. We used potassium ferricyanide to remove AgNO3 salts in cases of excessive chromosome impregnation. This method produced partial decolorization, with contrast enhancement. Counterstaining with Giemsa also promoted a better contrast between chromosome arms and NORs, which were preserved and retained a dark color. Application of this procedure to chromosome preparations treated sequentially for CBG banding/AgNO3 staining promoted complete decolorization of C+ regions, leading to "reverse" C-banding, generally with high contrast.
Electrophoretic analyses of peptidase-B were carried out on red cell hemolysates from Holstein, Mantiqueira and Gyr cattle, using cornstarch, known in Brazil as Penetrose-30. We describe a new peptidase-B allele, denoted Pep-B1, in Mantiqueira cattle, belonging to the Bos taurus group, which are the result of a cross of native cattle of Portuguese origin introduced in Brazil during colonial times (16th century) with Holstein and Caracu cattle. The genetic control of peptidase-B was determined by typing parents and progeny segregating for all three alleles, confirming that peptidase B is controlled by a single autosomal locus with three codominant alleles, denoted Pep-B1, Pep-B2 and Pep-B3 The use of the citrate-phosphate buffer system, at pH 5.9, on 14% gel, under the electrophoretic conditions standardized in this study permitted good visualization of all peptidase-B variants.
Plants were regenerated from leaf-derived callus culture of Stylosanthes scabra, a polyploid legume tolerant to drought and adapted to acid soils. A total of 168 regenerants were planted out in Leonard jars in a complete randomized design. Nitrogen fixation and vegetative growth were indirectly evaluated by shoot dry weight, root dry weight, shoot N content and acetylene reduction activity. The results showed higher variation in the regenerants than in controls not submitted to tissue culture. Significant differences were found for all nitrogen fixation related-traits.
Machado-Joseph disease (MJD) is a form of autosomal dominant spinocerebellar ataxia first described in North-American patients originating from the Portuguese islands of the Azores. Clinically this disorder is characterized by late onset progressive ataxia with associated features, such as: ophthalmoplegia, pyramidal and extrapyramidal signs and distal muscular atrophies. The causative mutation is an expansion of a CAG repeat in the coding region of the MJD1 gene. We have identified 25 unrelated families segregating the MJD mutation during a large collaborative study of spinocerebellar ataxias in Brazil. In the present study a total of 62 family members were genotyped for the CAG repeat in the MJD1 gene, as well as 63 non-MJD individuals (126 normal chromosomes), used as normal controls. We observed a wide gap between the size range of the normal and expanded CAG repeats: the normal allele had from 12 to 33 CAGs (mean = 23 CAGs), whereas the expanded alleles ranged from 66 to 78 CAGs (mean = 71.5 CAGs). There were no differences in CAG tract length according to gender of affected individuals or transmitting parent. We observed a significant negative correlation between age at onset of the disease and length of the CAG tract in the expended allele (r = -0.6, P = 0.00006); however, the size of the expanded CAG repeat could explain only about 40% of the variability in age at onset (r2 = 0.4). There was instability of the expanded CAG tract during transmission from parent to offspring, both expansions and contractions were observed; however, there was an overall tendency for expansion, with a mean increase of +2.4 CAGs. The tendency for expansion appeared to the greater in paternal (mean increase of +3.5 CAGs) than in maternal transmissions (mean increase of +1.3 CAGs). Anticipation was observed in all transmissions in which ages at onset for parent and offspring were known; however, anticipation was not always associated with an increase in the expanded CAG repeat length. Our results indicate that the molecular diagnosis of MJD can be confirmed or excluded in all suspected individuals, since alleles of intermediary size were not observed.
The brain is a very expensive organ in metabolic terms. Each unit of brain tissue requires over 22 times the amount of metabolic energy as an equivalent unit of muscle tissue. There is no correlation across mammals, however, between the relative size of the brain and the relative basal metabolic rate. The Expensive Tissue Hypothesis explains this apparent paradox by looking at the metabolic cost of the brain in the context of the costs of other metabolically expensive organs in the body. The results show that the increase in brain size in humans is balanced by an equivalent reduction in the size of the gastro-intestinal tract. In other words, the increased energetic demands of a relatively large brain are balanced by the reduced energy demands of a relatively small gastro-intestinal tract. This relationship also seems to be true in non-human primates.The size of the gastro-intestinal tract is dependent on both body size and the quality of the diet. It is argued that humans (and other primates) could not have developed a relatively large brain without also adopting a high quality diet that would have permitted a reduction in the relative size of the gastro-intestinal tract. Dietary change is therefore viewed as a 'prime releaser' in brain evolution. It is argued that a high quality diet is necessary for the evolution of a relatively large brain. However, the change to such a high quality diet, which involved an increased proportion of animal based products, need not have been one of the 'prime movers' in brain evolution. In this context, and based on the archaeological and palaeoanthropological record, the factors most probably surrounding the evolution of the human brain are discussed.
Two new Streptomyces phages, øBP1 and øBP2, were isolated from tropical soil samples. These phages presented a large host range and developed both lytic and lysogenic responses in different Streptomyces species tested. Variations in the incubation temperature showed to be important in the development of the replication cycle. Increasing incubation temperature from 30oC to 42oC induced the lytic response of øBP2 and lysogenic of øBP1 in the host strain Streptomyces sp. WL6. øBP1 and øBP2 have icosahedral heads with long tails and were characterized in relation to morphology, G + C content, genome size and adsorption curve
A study was made of the frequency of B-chromosomes and the population density of Astyanax scabripinnis paranae (Pisces, Characidae, Tetragonopterinae) from three stretches of the Cascatinha stream (Botucatu, SP). In the first stretch the population was estimated to be about 212 individuals and among 35 karyotyped specimens, 23 carried one macro B-chromosome; in the second stretch the population was estimated to be about 650 individuals and among 20 specimens karyotyped, two possessed one macro B-chromosome; in the third stretch the population was estimated to be about 107 individuals and among 10 specimens karyotyped, one carried one macro B-chromosome. A significant difference was observed in the frequency of macro B-chromosomes in females (57%) and males (8.7%) (P = 0.0001). These data suggest that the B-chromosome frequency and the populational density are not directly related. The hypothesis of the existence of some adaptive effect conferred by the B-chromosomes to the specimens from the first stretch of the Cascatinha stream is presented and discussed
The objective of the present study was to test three different procedures for DNA extraction of Melipona quadrifasciata based on existing methods for DNA extraction of Apis, plants and fungi. These methods differ in the concentrations of specific substances in the extraction buffer. The results demonstrate that the method used for Apis is not adequate for DNA extraction from M. quadrifasciata. On the other hand, with minor modifications this method and the methods for plants and fungi were adequate for DNA extraction of this stingless bee, both for adults and larvae.
The effect of two concentrations of caffeine (1500 mg/ml and 2500 mg/ml) on mitotic indices of Drosophila prosaltans was analyzed in larval brain cells. Although the differences detected between treated and control cells were not significant, the percentages obtained suggest a possible effect of caffeine in slowing the process of cell division
Chromosome numbers are reported for 127 germplasm accessions of Paspalum notatum maintained by EMBRAPA (Empresa Brasileira de Pesquisa Agropecuária) in two research centers in Brazil. Most accessions were collected in their natural habitats in Southern Brazil. Tetraploidy (2n = 40 chromosomes) was predominant (91% of the accessions studied), confirming previous reports for the species. Eleven accessions with 2n = 20 chromosomes, although collected in the wild, are possibly derived from 'Pensacola' bahiagrass, commonly cultivated in the area since its introduction from the United States in the 60's, for the establishment of permanent pastures.
A review of our recent work on the cromosomal evolution of the Drosophila repleta species group is presented. Most studies have focused on the buzzatii species complex, a monophyletic set of 12 species which inhabit the deserts of South America and the West Indies. A statistical analysis of the length and breakpoint distribution of the 86 paracentric inversions observed in this complex has shown that inversion length is a selected trait. Rare inversions are usually small while evolutionary successful inversions, fixed and polymorphic, are predominantly of medium size. There is also a negative correlation between length and number of inversions per species. Finally, the distribution of inversion breakpoints along chromosome 2 is non-random, with chromosomal regions which accumulate up to 8 breakpoints (putative "hot spots"). Comparative gene mapping has also been used to investigate the molecular organization and evolution of chromosomes. Using in situ hybridization, 26 genes have been precisely located on the salivary gland chromosomes of D. repleta and D. buzzatii; another nine have been tentatively identified. The results are fully consistent with the currently accepted chromosomal homologies between D. repleta and D. melanogaster, and no evidence for reciprocal translocations or pericentric inversions has been found. The comparison of the gene map of D. repleta chromosome 2 with that of the homologous chromosome 3R of D. melanogaster shows an extensive reorganization via paracentric inversions and allows to estimate an evolution rate of ~1 inversion fixed per million years for this chromosome
Intra and interspecific variability was measured in the genus Lycopersicon for the traits: productivity rate (PR, total number of regenerated shoots/total number of cultures), regeneration percentage (%R, number of cultures regenerating shoots or primordia/total number of cultures) and callus percentage (%C, number of cultures only producing callus/total number of cultures). Leaf explants from various genotypes of L. esculentum, L. esculentum var. cerasiforme, L. pimpinellifolium and L. peruvianum were placed on Murashige and Skoog (Physiol. Plant. 15: 473-493, 1962) medium + 0.175 mg/l IAA + 2.25 mg/l BA. Significant differences among species and among genotypes within the same species were found, while genotypes from different species showed similar responses.
Temperate and temperate x tropical germplasms were introduced into the maize breeding of the Department of Genetics (ESALQ-USP). Twenty populations designated as P-1 to P-20 and a check population were evaluated in a randomized complete block design with two replications at Piracicaba, SP, Brazil. Plots were 2.0 m long, spaced 1.0 m apart, with 10 plants per plot after thinning. The following traits were evaluated: PH, plant height; EH, ear height; TB, tassel branch number; KW, 100 kernels weight; EL, ear length; ED, ear diameter; KR, kernels per row, and RN, number of rows of kernels. The means of the exotic populations showed a variation in performance for all traits. The population means were greater than check means for KW, EL, and KR. Populations P-9, P-10, P-12, and P-13 showed low relative ear placement values (EH/PH index), indicating that these materials could contribute to lower ear placement in local populations. P-1 and P-9 showed a high potential to reduce TB. The phenotypic correlation coefficients among populations were positive for most combinations, except for RN with PH, EH, TB, and KW. Predictions of 19 composite means were obtained for all traits.
