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901.
Lilia Maria de Azevedo Moreira Acácia Fernandes Lacerda de Carvalho Ana Lúcia Vieira de Freitas Borja Paula Sanders Pereira Pinto Adriana Silveira Lucy Magalhães de Freitas Maria de Lourdes Lima Falcão 《Journal of applied genetics》2008,49(4):415-420
We report on the clinical observation of a girl patient with few signs of cri-du-chat syndrome. The chromosomal analysis in
lymphocyte culture showed 46,XX,del(5)(p15.3) in 38% of cells. Psychological tests revealed motor, perceptive and visual-spatial
problems, as well as immaturity and emotional dependence. The phoniatric evaluation showed poor vocabulary, difficulty with
repeating words or numbers in sequence, and better receptive than expressive language. The spectrographic measurements showed
disturbance of fundamental frequency (F0) in vocal pronunciation. The anatomic findings of the laryngoscopic evaluation were normal, indicating that the voice and
speech problems were functional disorders. The present case revealed moderate clinical signs and vocal disturbance associated
with a low percentage of 5p-cells and the breakpoint at 5p15.3. The short terminal deletion with a possible loss of the critical
region for cat-like cry and the presence of a normal cell line, explain the cry not so typical at birth (weak but not high-pitched),
the intermediate values of F0, and the moderate mental retardation. This case is compared with other mosaic 5p-patients reported in the literature. 相似文献
902.
Marques AF da Silva MB Juliano MA Munhõz JE Travassos LR Taborda CP 《Microbes and infection / Institut Pasteur》2008,10(12-13):1251-1258
Paracoccidioidomycosis is a systemic granulomatous disease manifested in the acute/subacute or chronic forms. The anergic cases of the acute/subacute form are most severe, leading to death threatening conditions. Drug treatment is required to control the disease but the response in anergic patients is generally poor. A 15-mer peptide from the major diagnostic antigen gp43, named P10, induces a T-CD4+ helper-1 immune response in mice of different haplotypes and protects against intratracheal challenge with virulent P. brasiliensis. Presently, P10 immunization and chemotherapy were associated in an attempt to improve antifungal treatment in Balb/c mice made anergic by adding dexamethasone to the drinking water. The combined drug/peptide treatment significantly reduced the lung CFUs in infected anergic mice, largely preserved lung alveolar structure and prevented fungal dissemination to liver and spleen. Results recommend that a P10-based vaccine should be associated to chemotherapy for improved treatment of paracoccidioidomycosis aiming especially at anergic cases. 相似文献
903.
Morchón R Rodríguez-Barbero A Velasco S López-Belmonte J Simón F 《Parasitology international》2008,57(4):441-446
Dirofilaria immitis is the causal agent of cardiopulmonary dirofilariosis (heartworm disease). Adult worms lodge in the pulmonary arteries and right ventricle, thus vascular endothelium is exposed to high concentrations of Dirofilaria antigenic products. Heartworm disease habitually develops as a chronic foreseeable pathology. Moreover, the simultaneous death of many adult worms, naturally or induced by a filaricide treatment, can cause acute thromboembolisms and endarteritis. To better understand the effects of the massive death of D. immitis adult worms on the blood vessel endothelium, we cultured vascular endothelial cells in the presence or absence of an antigenic extract of D. immitis adult worms (DiSA). The parasite products increased the expression of enzymes and the synthesis of eicosanoids related to inflammation, such as COX-2, 5-LO, PGE2 and LTB4. The expression of ICAM-1 and PECAM-1 adhesion molecules and endothelial and inducible Nitric Oxide Synthases (eNOS and iNOS) was also increased in cultures treated with DiSA. Nevertheless, DiSA decreased endothelial permeability and does not alter both proliferation and apoptosis. These results suggest that the somatic extract of D. immitis adult worms stimulate inflammatory mechanisms in endothelial cells, without altering their basic physiologic processes. 相似文献
904.
Repullés-Albelda A Montero FE Holzer AS Ogawa K Hutson KS Raga JA 《Parasitology international》2008,57(3):405-414
Two new species of teleost blood fluke belonging to the sanguinicolid genus Paradeontacylix are described from the greater amberjack, Seriola dumerili, i.e. Paradeontacylix ibericus n. sp. from the Iberian Peninsula and Paradeontacylix balearicus n. sp. from the Balearic Islands. P. ibericus n. sp. and P. balearicus n. sp. show morphological similarities with Paradeontacylix kampachi and Paradeontacylix grandispinus respectively, which occur in mixed infection in S. dumerili from Japan. Multivariate analysis of morphometrical data provided statistical evidence for the separation of four species. However, component by component analysis did not show statistically significant differences between P. balearicus and P. grandispinus. Molecular data based on rITS2 and mCO1 gene sequences also supported the separation into four species. Morphological and molecular data were used to examine phylogenetic relationships between Paradeontacylix species from S. dumerili and other species in the genus. The results coincided in revealing two main branches with P. kampachi+P. ibericus and (((P. grandispinus+P. balearicus) Paradeontacylix sanguinicoloides) Paradeontacylix godfreyi). Paradeontacylix odhneri, for which little data are available, was located basal in a separate branch. This is the only species of Paradeontacylix which parasitizes a non-carangid host which might probably explain the separation from the other species. Paired similarities between the Japanese and the Mediterranean species, despite the large geographic distance, could be explained by the speciation of parasite geminate lines before host separation by tectonic events. Consequently, geographic and historical isolation support the morphological and genetic differences leading to the evolution of the new species described here. 相似文献
905.
Laura Alonso-Sáez Evaristo Vázquez-Domínguez Clara Cardelús Jarone Pinhassi M. Montserrat Sala Itziar Lekunberri Vanessa Balagué Maria Vila-Costa Fernando Unrein Ramon Massana Rafel Simó Josep M. Gasol 《Ecosystems》2008,11(3):397-409
Data from several years of monthly samplings are combined with a 1-year detailed study of carbon flux through bacteria at
a NW Mediterranean coastal site to delineate the bacterial role in carbon use and to assess whether environmental factors
or bacterial assemblage composition affected the in situ rates of bacterial carbon processing. Leucine (Leu) uptake rates
[as an estimate of bacterial heterotrophic production (BHP)] showed high interannual variability but, on average, lower values
were found in winter (around 50 pM Leu−1 h−1) as compared to summer (around 150 pM Leu−1 h−1). Leu-to-carbon conversion factors ranged from 0.9 to 3.6 kgC mol Leu−1, with generally higher values in winter. Leu uptake was only weakly correlated to temperature, and over a full-year cycle
(in 2003), Leu uptake peaked concomitantly with winter chlorophyll a (Chl a) maxima, and in periods of high ectoenzyme activities in spring and summer. This suggests that both low molecular weight
dissolved organic matter (DOM) released by phytoplankton, and high molecular weight DOM in periods of low Chl a, can enhance BHP. Bacterial respiration (BR, range 7–48 μg C l−1 d−1) was not correlated to BHP or temperature, but was significantly correlated to DOC concentration. Total bacterial carbon
demand (BHP plus BR) was only met by dissolved organic carbon produced by phytoplankton during the winter period. We measured
bacterial growth efficiencies by the short-term and the long-term methods and they ranged from 3 to 42%, increasing during
the phytoplankton blooms in winter (during the Chl a peaks), and in spring. Changes in bacterioplankton assemblage structure (as depicted by denaturing gradient gel electrophoresis
fingerprinting) were not coupled to changes in ecosystem functioning, at least in bacterial carbon use. 相似文献
906.
The autoimmune regulator PHD finger binds to non-methylated histone H3K4 to activate gene expression 总被引:2,自引:0,他引:2
Org T Chignola F Hetényi C Gaetani M Rebane A Liiv I Maran U Mollica L Bottomley MJ Musco G Peterson P 《EMBO reports》2008,9(4):370-376
Mutations in the gene autoimmune regulator (AIRE) cause autoimmune polyendocrinopathy candidiasis ectodermal dystrophy. AIRE is expressed in thymic medullary epithelial cells, where it promotes the expression of tissue-restricted antigens. By the combined use of biochemical and biophysical methods, we show that AIRE selectively interacts with histone H3 through its first plant homeodomain (PHD) finger (AIRE-PHD1) and preferentially binds to non-methylated H3K4 (H3K4me0). Accordingly, in vivo AIRE binds to and activates promoters containing low levels of H3K4me3 in human embryonic kidney 293 cells. We conclude that AIRE-PHD1 is an important member of a newly identified class of PHD fingers that specifically recognize H3K4me0, thus providing a new link between the status of histone modifications and the regulation of tissue-restricted antigen expression in thymus. 相似文献
907.
Kai Truusalu Raik-Hiio Mikelsaar Paul Naaber Tõnis Karki Tiiu Kullisaar Mihkel Zilmer Marika Mikelsaar 《BMC microbiology》2008,8(1):132
Background
The aim of the study was to detect whether in experimental Salmonella enterica Typhimurium infection the probiotic Lactobacillus fermentum ME-3 in combination with fluoroquinolone therapy would eradicate S. Typhimurium, prevent the development of liver and spleen granulomas and improve the indices of oxidative stress in the ileum mucosa. 相似文献908.
Carreiro da Costa RS Prudêncio L Ferrari EF Souza GH de Mello SM Prianti Júnior AC Ribeiro W Zamunér SR Hyslop S Cogo JC 《Comparative biochemistry and physiology. Toxicology & pharmacology : CBP》2008,148(1):31-38
Snakes of the opisthoglyphous genus Philodryas are widespread in South America and cause most bites by colubrids in this region. In this study, we examined the neurotoxic and myotoxic effects of venom from Philodryas patagoniensis in biventer cervicis and phrenic nerve-diaphragm preparations and we compared the biochemical activities of venoms from P. patagoniensis and Philodryas olfersii. Philodryas patagoniensis venom (40 microg/mL) had no effect on mouse phrenic nerve-diaphragm preparations but caused time-dependent neuromuscular blockade of chick biventer cervicis preparations. This blockade was not reversed by washing. The highest concentration of venom tested (40 microg/mL) significantly reduced (p<0.05) the contractures to exogenous acetylcholine (55 microM and 110 microM) and K(+) (13.4 mM) after 120 min; lower concentrations of venom had no consistent or significant effect on these responses. Venom caused a concentration- and time-dependent release of creatine kinase (CK) from biventer cervicis preparations. Histological analysis showed contracted muscle fibers at low venom concentrations and myonecrosis at high concentrations. Philodryas venoms had low esterase and phospholipase A(2) but high proteolytic activities compared to the pitviper Bothrops jararaca. SDS-PAGE showed that the Philodryas venoms had similar electrophoretic profiles, with most proteins having a molecular mass of 25-80 kDa. Both of the Philodryas venoms cross-reacted with bothropic antivenom in ELISA, indicating the presence of proteins immunologically related to Bothrops venoms. RP-HPLC of P. patagoniensis venom yielded four major peaks, each of which contained several proteins, as shown by SDS-PAGE. These results indicate that P. patagoniensis venom has neurotoxic and myotoxic components that may contribute to the effects of envenoming by this species. 相似文献
909.
Roux-Dalvai F Gonzalez de Peredo A Simó C Guerrier L Bouyssié D Zanella A Citterio A Burlet-Schiltz O Boschetti E Righetti PG Monsarrat B 《Molecular & cellular proteomics : MCP》2008,7(11):2254-2269
The erythrocyte cytoplasmic proteome is composed of 98% hemoglobin; the remaining 2% is largely unexplored. Here we used a combinatorial library of hexameric peptides as a capturing agent to lower the signal of hemoglobin and amplify the signal of low to very low abundance proteins in the cytoplasm of human red blood cells (RBCs). Two types of hexapeptide library beads have been adopted: amino-terminal hexapeptide beads and beads in which the peptides have been further derivatized by carboxylation. The amplification of the signal of low abundance and suppression of the signal of high abundance species were fully demonstrated by two-dimensional gel maps and nano-LC-MSMS analysis. The effect of this new methodology on quantitative information also was explored. Moreover using this approach on an LTQ-Orbitrap mass spectrometer, we could identify with high confidence as many as 1578 proteins in the cytoplasmic fraction of a highly purified preparation of RBCs, allowing a deep exploration of the classical RBC pathways as well as the identification of unexpected minor proteins. In addition, we were able to detect the presence of eight different hemoglobin chains including embryonic and newly discovered globin chains. Thus, this extensive study provides a huge data set of proteins that are present in the RBC cytoplasm that may help to better understand the biology of this simplified cell and may open the way to further studies on blood pathologies using targeted approaches. 相似文献
910.