Albinism in plants - far beyond the loss of chlorophyll: Structural and physiological aspects of wild-type and albino royal poinciana (Delonix regia) seedlings.

The partial or complete loss of chlorophylls, or albinism, is a rare phenomenon in plants. In the present study, we provide the first report of the occurrence in albino Delonix regia seedlings and describe the morpho-physiological changes associated with albinism. Wild-type (WT) and albino seedlings were characterized. Leaflets samples were processed following common procedures for analysis with light, scanning and transmission electron microscopy. The chlorophyll a fluorescence parameters and the carbohydrate, lipid and soluble protein content were also determined in leaf and cotyledon samples of both albino and WT seedlings. Albino seedlings showed reduced growth. They also had lower chlorophyll and protein content in foliar tissues than WT seedlings, in addition to lower concentrations of lipids and carbohydrates stored in cotyledons. The chloroplasts of albino seedlings were poorly developed, with an undefined internal membrane system and the presence of plastoglobules. Wild-type seedlings had a uniseriate and hypoestomatic epidermis. The mesophyll was dorsiventral, consisting of a layer of palisade parenchyma and two to four layers of spongy parenchyma. In albino seedlings, the spongy parenchyma was compact, with few intercellular spaces, and the thickness of the mesophyll was larger, resulting in increased thickness of the leaf blade. Albino seedlings had higher stomatal density and number of pavement cells, although the stomata had smaller dimensions. In addition to the partial loss of chlorophylls, albino D. regia showed changes at physiological and structural levels, demonstrating the crucial nature of photosynthetic pigments during the development and differentiation of plant leaf tissues/cells.

Bone demineralization in the lumbar spine of dogs submitted to prednisone therapy.

Glucocorticoids are drugs widely used in veterinary medicine; however, besides their clinical benefits, their use can trigger undesirable effects. A clinical trial was performed on eight healthy dogs with the intent of evaluating possible alterations in the bone mineral density after therapy with prednisone using a helical computed tomography. All animals received prednisone orally at a dose of 2 mg/kg of weight for 30 days. The bone mineral density was determined by obtaining the vertebral body radiodensity of the second lumbar vertebra values immediately before and after the administration of the medication. The experimental protocol allowed for the characterization of a significant (P < 0.01) reduction of the vertebral body radiodensity of the second lumbar vertebra. At the end of the experiment, it was characterized by a loss of bone mass of approximately 14%. None of the animals presented pathologic fracture at the end of the administration of the medication. This study verified that the alterations in the bone metabolism of the dogs submitted to the therapy with prednisone in a dosage of 2 mg/kg occur rapidly, which recommends a monitoring of the patients for the prevention of pathologic fractures.

Report from the killer immunoglobulin-like receptor (KIR) anthropology component of the 15th International Histocompatibility Workshop: worldwide variation in the KIR loci and further evidence for the co-evolution of KIR and HLA.

The killer immunoglobulin-like receptor (KIR) anthropology component of the 15th International Histocompatibility Workshop (IHIWS) sought to explore worldwide population variation in the KIR loci, and to examine the relationship between KIR genes and their human leukocyte antigen (HLA) ligands. Fifteen laboratories submitted KIR genotype and HLA ligand data in 27 populations from six broad ethnic groups. Data were analyzed for correlations between the frequencies of KIR and their known HLA ligands. In addition, allelic typing was performed for KIR2DL2 and 3DL1 in a subset of populations. Strong and significant correlations were observed between KIR2DL2, 2DL3 genotype frequencies and the frequency of their ligand, HLA-C1. In contrast, only weak associations were seen for 3DL1, 3DS1 and the HLA-Bw4 ligand. Although some aspects of the correlations observed here differ from those reported in other populations, these data provide additional evidence of linked evolutionary histories for some KIR and HLA loci. Investigation of allele-level variation for the B haplotype locus KIR 2DL2 showed that two alleles, *001 and *003, predominate in all populations in this study. Much more allelic variation was observed for the A haplotype locus 3DL1, with several alleles observed at moderate frequencies and extensive variation observed between populations.

Analysis of the HLA population data (AHPD) submitted to the 15th International Histocompatibility/Immunogenetics Workshop by using the Gene[rate] computer tools accommodating ambiguous data (AHPD project report).

During the 15th International Histocompatibility and Immunogenetics Workshop (IHIWS), 14 human leukocyte antigen (HLA) laboratories participated in the Analysis of HLA Population Data (AHPD) project where 18 new population samples were analyzed statistically and compared with data available from previous workshops. To that aim, an original methodology was developed and used (i) to estimate frequencies by taking into account ambiguous genotypic data, (ii) to test for Hardy-Weinberg equilibrium (HWE) by using a nested likelihood ratio test involving a parameter accounting for HWE deviations, (iii) to test for selective neutrality by using a resampling algorithm, and (iv) to provide explicit graphical representations including allele frequencies and basic statistics for each series of data. A total of 66 data series (1-7 loci per population) were analyzed with this standard approach. Frequency estimates were compliant with HWE in all but one population of mixed stem cell donors. Neutrality testing confirmed the observation of heterozygote excess at all HLA loci, although a significant deviation was established in only a few cases. Population comparisons showed that HLA genetic patterns were mostly shaped by geographic and/or linguistic differentiations in Africa and Europe, but not in America where both genetic drift in isolated populations and gene flow in admixed populations led to a more complex genetic structure. Overall, a fruitful collaboration between HLA typing laboratories and population geneticists allowed finding useful solutions to the problem of estimating gene frequencies and testing basic population diversity statistics on highly complex HLA data (high numbers of alleles and ambiguities), with promising applications in either anthropological, epidemiological, or transplantation studies.

Antiprotozoal effect of crude extracts and flavonoids isolated from Chromolaena hirsuta (asteraceae).

Phytochemical study of Chromolaena hirsuta (Hook. & Arn.) R. King & H. Robinson crude extract (collected in Furnas, MG-Brasil) produced fifteen flavonoids, two triterpenes and five steroids. IR, UV,(1)H and (13)C NMR spectroscopy and GC analysis were used for the identification of these compounds. The dichloromethanic and ethanolic crude extracts (flowers and leaves) and six flavonoids isolated from this specie have been assayed for antiprotozoal activity against tripomastigote forms of Trypanosoma cruzi and promastigote forms of Leishmania amazonensis. The crude extracts significantly reduced the viability of T. cruzi and Leishmania amazonensis, and the six flavonoids showed considerable antiproliferative effect of development of two parasites evaluated. This is the fi rst report of antiprotozoal activity of extracts of C. hirsuta.

[Social representations of health and disease and the implications in nursing care: a structural analysis]. / Representações sociais da saúde e doença e implicações para o cuidar em enfermagem: uma análise estrutural.

This study characterizes the social representations of the health-disease process of subjects resident in two districts of São Paulo, in order to identify the needs of health and the orientation of the nursing action. Free evocations recollections from 418 adults on the themes health and disease. Data analyse was developed thought a descriptive and structural analysis of the social representations, through the methodology of construction of the "picture of four houses", categorization and similitude analysis. The results show central senses of the representation, the possitiveness of the health, are anchored in a divine entity, and accompanied of notions that associate health to prevention of diseases, to biological needs, to activity and to which the attitude assumed to the disease. The representation structure of disease is similar, in inverse sense, to the one of the health: god is the center of the social representation, in its negative version, being expressed in the body through the pain, of the death and the inactivity and--in the spirit--through the sadness and of the depression. The discussion is that psychological character of health and of disease, that is expressed under the psychosocial needs committed, and the consequent need of rethinking the technological model of work in nursing.