994 resultados para molecular types
Resumo:
We present a 20-year follow-up on a patient with a ring chromosome 14. The ring chromosome was studied by fluorescence in-situ hybridization (FISH), multiplex-ligation probe amplification (MLPA), and genome wide SNP array, and no deletions of chromosome 14 were detected, although the telomeric repeat sequence was absent from the ring chromosome. The patient had skeletal abnormalities, and susceptibility to infections, as well as seizures and retinal pigmentation, which are commonly found in individuals with a ring 14. Our patient corroborates the idea that even when no genes are lost during ring formation, a complete ring chromosome can produce phenotypic alterations, which presumably result from ring instability or gene silencing due to the new chromosomal architecture. (C) 2010 Wiley-Liss, Inc.
Resumo:
Peptides constitute the largest group of Hymenoptera venom toxins; some of them interact with GPCR, being involved with the activation of different types of leukocytes, smooth muscle contraction and neurotoxicity. Most of these toxins vary from dodecapeptides to tetradecapeptides, amidated at their C-teminal amino acid residue. The venoms of social wasps can also contains some tetra-, penta-, hexa- and hepta-peptides, but just a few of them have been structurally and functionally characterized up to now. Protonectin (ILG-TILGLLKGL-NH(2)) is a polyfunctional peptide, presenting mast cell degranulation, release of lactate dehydrogenase (LDH) from mast cells, antibiosis against Gram-positive and Gram-negative bacteria and chemotaxis for polymorphonucleated leukocytes (PMNL), while Protonectin (1-6) (ILGTIL-NH(2)) only presents chemotaxis for PMNL However, the mixture of Protonectin (1-6) with Protonectin in the molar ratio of 1:1 seems to potentiate the biological activities dependent of the membrane perturbation caused by Protonectin, as observed in the increasing of the activities of mast cell degranulation, LDH releasing from mast cells, and antibiosis. Despite both peptides are able to induce PMNL chemotaxis, the mixture of them presents a reduced activity in comparison to the individual peptides. Apparently, when mixed both peptides seems to form a supra-molecular structure, which interact with the receptors responsible for PMNL chemotaxis, disturbing their individual docking with these receptors. In addition to this, a comparison of the sequences of both peptides suggests that the sequence ILGTIL is conserved, suggesting that it must constitute a linear motif for the structural recognition by the specific receptor which induces leukocytes migration. (C) 2010 Elsevier Ltd. All rights reserved.
Resumo:
Deletion of the long arm of chromosome 18 is one of the most common segmental aneusomies compatible with life and usually involves a deletion of the terminal chromosomal region. However, the mechanisms implicated in the stabilization of terminal deletions are not well understood. In this study, we analyzed a girl with moderate mental retardation who had a cytogenetically visible terminal 18q deletion. In order to characterize the breakpoint in the terminal 18q region, we used fluorescence In situ hybridization (FISH) with bacterial artificial chromosomes (BACs) and pan-telomeric probes and also the array technique based on comparative genomic hybridization (array-CGH). FISH with pan-telomeric probes revealed no signal in the terminal region of the deleted chromosome, indicating the absence of normal telomere repeat (TTAGGG)n sequences in 18q. We suggest that neo-telomere formation by chromosome healing was involved in the repair and stabilization of this terminal deletion. (C) 2010 Elsevier Masson SAS. All rights reserved.
Resumo:
Angiomatoid ""malignant"" fibrous histiocytoma is a rare sarcoma of low malignant potential that occurs most commonly in the extremities of children and young adults. Herein, we present a case of angiomatoid malignant fibrous histiocytoma with unusual histologic features arising in the mediastinum of an 80-year-old man. The tumor exhibited a reticular growth pattern and myxoid stroma. The tumor cells expressed epithelial membrane antigen and desmin. Cytogenetic analysis revealed the translocation t(2;22)(q33;q12). Molecular genetic analysis confirmed the rearrangement of the EWSR1 locus and the presence of the EWSR1/CREB1 fusion. This report expands the clinicopathologic spectrum of angiomatoid malignant fibrous histiocytoma and underscores the value of integrating morphologic, immunophenotypic, and molecular findings in the identification of its unusual morphologic variants. (C) 2011 Elsevier Inc. All rights reserved.
Resumo:
Although human T-cell lymphotropic virus type 2 (HTLV-2) is considered of low pathogenicity, serological diagnosis is important for counseling and monitoring. The confirmatory tests most used are Western blot (WB) and PCR. However, in high-risk populations, about 50% of the indeterminate WB were HTLV-2 positives by PCR. The insensitivity of the WB might be due to the use of recombinant proteins of strains that do not circulate in our country. Another possibility may be a high level of immunosuppression, which could lead to low production of virus, resulting in low stimulation of antibody. We found one mutation, proline to serine in the envelope region in the position 184, presented at least 1/3 of the samples, independent the indeterminate WB profile. In conclusion, we found no correlation of immune state, HTLV-2 proviral load, or env diversity in the K55 region and WB indeterminate results. We believe that the only WB kit available in the market is probably more accurate to detect HTLV-1 antibodies, and some improvement for HTLV-2 detection should be done in the future, especially among high-risk population. J. Med. Virol. 82:837-842,2010. (C) 2010 Wiley-Liss, Inc.
Resumo:
The higher frequency of triple-negative and HER-2-positive tumors detected in younger patients has been suggested as an explanation for the more aggressive tumor types observed in this age group. However, estrogen receptor (ER)-positive tumors are the most frequent subtype of breast carcinomas identified, even in younger patients. In this retrospective study, the morphological and immunohistochemical profiles of ER-positive breast carcinomas from women 35 yrs and younger that were diagnosed between 1997 and 2007 were evaluated. From these cases, 213 were selected based on the availability of pathology reports and paraffin blocks. For comparison, 117 consecutive cases of breast carcinomas diagnosed in patients >60 yrs from 2006 were included. Paraffin-embedded tumors were stained for expression of ER, progesterone receptor (PR), human epidermal growth factor receptor 2 (HER-2). Ki-67 antigen, epidermal growth factor receptor (EGFR), cytokeratin 5/6, p53, vimentin, CD117, and p63 using tissue microarrays. ER-positive carcinomas were diagnosed in 120 (56.1%) samples of the younger patient group and in 92 (78.6%) samples of the older patient group. Of these ER-positive carcinomas, 48 (40%) from the younger patient group presented the subtype luminal A, compared with 53 (57.6%) from the older patient group (p=0.01). Tumors from the younger patient group were also associated with increased vascular involvement, co-expression of HER-2, and decreased expression of CD117. These results highlight differences in expression markers and the pathology of ER-positive tumors detected in younger women, with a notable characteristic being co-expression of HER-2. (C) 2010 Elsevier Ltd. All rights reserved.
Resumo:
P>We have developed a two-step PCR assay that amplifies a region of the ceja-1 sequence that is specific for virulent strains of Paracoccidioides brasiliensis. An internal region of the ceja-1 sequence was chosen for designing primers that were utilised in a single tube heminested PCR protocol to amplify DNA from six virulent strains. PCR specificity was determined by the absence of amplified products with genomic DNA from four non-virulent strains of P. brasiliensis and from eight fungal pathogens, one bacterium, two protozoa, one worm and mouse and human genomic DNA (leucocytes). The fact that the PCR product was only obtained with the genetic material from virulent isolates of P. brasiliensis suggested that this partial amplified sequence might be a marker of virulence for this fungus. The diagnostic potential of this PCR was confirmed by the successful amplification of this fragment with genomic DNA obtained in lymph node aspirate from a patient with paracoccidioidomycosis.
Resumo:
Intrapleural instillation of talc has been used in the treatment of recurrent pleural effusions but can, in rare instances, result in respiratory failure. Side-effects seem to be related to composition, size and inflammatory power of talc particles. The aim of this study was to evaluate the inflammatory response to intrapleural injection of talc containing small particles (ST) or talc containing particles of mixed size (MT). 100 rabbits received intrapleural talc, 50 with ST (median 6.41 mu m) and 50 with MT median 21.15 mu m); the control group was composed of 35 rabbits. Cells, lactate dehydrogenase, C-reactive protein (CRIP), interleukin (IL)-8 and vascular endothelial growth factor were evaluated in serum and bronchoalveolar lavage at 6, 24, 48, 72 and 96 h. Lung histology and the presence of talc were also analysed. Statistics were performed using ANOVA and an unpaired t-test. Most of the parameters showed greater levels in the animals injected with talc than in the controls, suggesting a systemic and pulmonary response. Higher serum levels of CRP and IL-8 were observed in the animals injected with ST. Talc particles were observed in both lungs with no differences between groups. Lung cell infiltrate was more evident in the ST group. In conclusion, talc with larger particles should be the preferred choice in clinical practice in order to induce safer pleurodesis.
Resumo:
Purpose: We tested whether the combination of 4 established cell cycle regulators (p53, pRB, p21 and p27) could improve the ability to predict clinical outcomes in a large multi-institutional collaboration of patients with pT3-4N0 or pTany Npositive urothelial carcinoma of the bladder. We also assessed whether the combination of molecular markers is superior to any individual biomarker. Materials and Methods: The study comprised 692 patients with pT3-4N0 or pTany Npositive urothelial carcinoma of the bladder treated with radical cystectomy and bilateral lymphadenectomy (median followup 5.3 years). Scoring was performed using advanced cell imaging and color detection software. The base model incorporated patient age, gender, stage, grade, lymphovascular invasion, number of lymph nodes removed, number of positive lymph nodes, concomitant carcinoma in situ and adjuvant chemotherapy. Results: Individual molecular markers did not improve the predictive accuracy for disease recurrence and cancer specific mortality. Combination of all 4 molecular markers into number of altered molecular markers resulted in significantly 1 higher predictive accuracy than any single biomarker (p < 0.001.). Moreover addition of number of altered molecular markers to the base model significantly improved the predictive accuracy for disease recurrence (3.9%, p < 0.001) and cancer specific mortality (4.3%, p < 0.001). Addition of number of altered molecular markers retained statistical significance for improving the prediction of clinical outcomes in the subgroup of patients with pT3N0 (280), pT4N0 (83) and pTany Npositive (329) disease (p < 0.001). Conclusions: While the status of individual molecular markers does not add sufficient value to outcome prediction in patients with advanced urothelial carcinoma of the bladder, combinations of molecular markers may improve molecular staging, prognostication and possibly prediction of response to therapy.
Resumo:
Pulp softening is one of the most remarkable changes during ripening of papaya (Carica papaya) fruit and it is a major cause for post-harvest losses. Although cell wall catabolism has a major influence on papaya fruit, quality information on the gene products involved in this process is limited. A full-length polygalacturonase cDNA (cpPG) was isolated from papaya pulp and used to study gene expression and enzyme activity during normal and ethylene-induced ripening and after exposure of the fruit to 1-MCP. Northern-blot analysis demonstrated that cpPG transcription was strongly induced during ripening and was highly ethylene-dependent. The accumulation of cpPG transcript was paralleled by enzyme activity, and inversely correlated to the pulp firmness. Preliminary in silica analysis of the cpPG genomic sequence revealed the occurrence of putative regulatory motifs in the promoter region that may help to explain the effects of plant hormones and non-abiotic stresses on papaya fruit firmness. This newly isolated cpPG is an important candidate for functional characterization and manipulation to control the process of pulp softening during papaya ripening. (C) 2009 Elsevier Masson SAS. All rights reserved.
Linking biophysical and genetic models to integrate physiology, molecular biology and plant breeding
Resumo:
Retinal neurons with distinct dendritic morphologies are likely to comprise different cell types, subject to three important caveats. First, it is necessary to avoid creating “artificial” cell types based on arbitrary criteria—for example, the presence of two or three primary dendrites. Second, it is essential to take into account changes in morphology with retinal eccentricity and cell density. Third, the retina contains imperfections like any natural system and a significant number of retinal neurons display aberrant morphologies or make aberrant connections that are not typical of the population as a whole. Many types of retinal ganglion cells show diverse patterns of tracer coupling, with the simplest pattern represented by the homologous coupling shown by On-Off direction-selective (DS) ganglion cells in the rabbit retina. Neighboring DS ganglion cells with a common preferred direction have regularly spaced somata and territorial dendritic fields, whereas DS ganglion cells with different preferred directions may have closely spaced somata and overlapping dendritic fields.
Resumo:
Papaya (Carica papaya) is a climacteric fruit that undergoes dramatic pulp softening. Fruits sampled at three different conditions (natural ripening or after exposition to ethylene or 1-methylcyclopropene) were used for the isolation of cell wall polymers to find changes in their degradation pattern. Polymers were separated according to their solubility in water, CDTA, and 4 M alkali, and their monosaccharide compositions were determined. Water-soluble polymers were further characterized, and their increased yields in control and ethylene-treated fruit, in contrast to those that were treated with 1-MCP, indicated a strong association between fruit softening and changes in the cell wall water-soluble polysaccharide fraction. The results indicate that the extensive softening in the pulp of ripening papayas is a consequence of solubilization of large molecular mass galacturonans from the pectin fraction of the cell wall. This process seems to be dependent on the levels of ethylene, and it is likely that the releasing of galacturonan chains results from an endo acting polygalacturonase.
Resumo:
Autoimmune bullous dermatoses are diseases in which blisters and vesicles are the primary and fundamental types of skin lesion. Their classification is based on the location of the blister; intraepidermal and subepidermal. Patients produce autoantibodies against self-specific structures of the skin detectable by immunofluorescence techniques, immunoblotting and ELISA. Recent advances in molecular and cellular biology have brought to knowledge these self-antigens, against which patients are sensitized, and which are found in epidermis or in the dermo-epidermal junction. These are low incidence, but high morbidity diseases that may be fatal. The aim of this article is to review and describe the progress of four autoimmune vesiculobullous disorders; endemic pemphigus foliaccous (wild fire), pemphigus vulgaris, bullous pemphigoid and dermatitis herpetiformis.