Publish in OALib Journal

ISSN: 2333-9721

APC: Only $99


Any time

2020 ( 1 )

2019 ( 195 )

2018 ( 254 )

2017 ( 259 )

Custom range...

Search Results: 1 - 10 of 151568 matches for " Joana B. Melo "
All listed articles are free for downloading (OA Articles)
Page 1 /151568
Display every page Item
X-chromosome terminal deletion in a female with premature ovarian failure: Haploinsufficiency of X-linked genes as a possible explanation
Susana I Ferreira, Eunice Matoso, Marta Pinto, Joana Almeida, Thomas Liehr, Joana B Melo, Isabel M Carreira
Molecular Cytogenetics , 2010, DOI: 10.1186/1755-8166-3-14
Abstract: Concomitant analysis of FMR1 gene CGG repeat number and karyotype revealed an X-chromosome terminal deletion. Fluorescence in situ further characterized the breakpoint. A methylation assay for FMR1 gene allowed to determine its methylation status, and hence, the methylation status of the normal X-chromosome.We report a POF patient with a 46,X,del(X)(q26) karyotype and with skewed X-chromosome inactivation of the structural abnormal X-chromosome.Despite the hemizygosity of FMR1 gene, the patient does not present Fragile X syndrome features, since the normal X-chromosome is not subject to methylation. The described deletion supports the hypothesis that haploinsufficiency of X-linked genes can be on the basis of POF, and special attention should be paid to X-linked genes in region Xq28 since they escape inactivation and might have a role in this disorder. A full clinical and cytogenetic characterization of all POF cases is important to highlight a pattern and help to understand which genes are crucial for normal ovarian development.Premature ovarian failure (POF) is an early ovarian dysfunction characterized by the cessation of menses before the age of 40 years [1,2] that affects 1% of women [3]. The diagnosis is established by the presence of FSH (follicle stimulating hormone) serum level higher than 40 mIU/ml [4], detected on at least two occasions a few weeks apart [5]. Although the exact etiology is still unknown, several causes have been associated with POF and may include autoimmunity, infections, iatrogenesis and a strong genetic component, that can vary from single gene alterations to chromosome abnormalities [6].X;autosome balanced translocations and X-chromosome deletions have been reported in POF patients, leading to the identification of two main critical regions for normal ovarian function on the long arm of this chromosome, specifically at Xq13-q21 [7] and Xq26-q27 [4,8]. In the case of X;autosome balanced translocations, these can either lead to gene dis
Estimating the Above-Ground Biomass in Miombo Savanna Woodlands (Mozambique, East Africa) Using L-Band Synthetic Aperture Radar Data
Jo?o M. B. Carreiras,Joana B. Melo,Maria J. Vasconcelos
Remote Sensing , 2013, DOI: 10.3390/rs5041524
Abstract: The quantification of forest above-ground biomass (AGB) is important for such broader applications as decision making, forest management, carbon (C) stock change assessment and scientific applications, such as C cycle modeling. However, there is a great uncertainty related to the estimation of forest AGB, especially in the tropics. The main goal of this study was to test a combination of field data and Advanced Land Observing Satellite (ALOS) Phased Array L-band Synthetic Aperture Radar (PALSAR) backscatter intensity data to reduce the uncertainty in the estimation of forest AGB in the Miombo savanna woodlands of Mozambique (East Africa). A machine learning algorithm, based on bagging stochastic gradient boosting (BagSGB), was used to model forest AGB as a function of ALOS PALSAR Fine Beam Dual (FBD) backscatter intensity metrics. The application of this method resulted in a coefficient of correlation (R) between observed and predicted (10-fold cross-validation) forest AGB values of 0.95 and a root mean square error of 5.03 Mg·ha ?1. However, as a consequence of using bootstrap samples in combination with a cross validation procedure, some bias may have been introduced, and the reported cross validation statistics could be overoptimistic. Therefore and as a consequence of the BagSGB model, a measure of prediction variability (coefficient of variation) on a pixel-by-pixel basis was also produced, with values ranging from 10 to 119% (mean = 25%) across the study area. It provides additional and complementary information regarding the spatial distribution of the error resulting from the application of the fitted model to new observations.
Critical region in 2q31.2q32.3 deletion syndrome: Report of two phenotypically distinct patients, one with an additional deletion in Alagille syndrome region
Susana Isabel Ferreira, Eunice Matoso, Margarida Venancio, Jorge Saraiva, Joana B Melo, Isabel Marques Carreira
Molecular Cytogenetics , 2012, DOI: 10.1186/1755-8166-5-25
Abstract: We report two female patients with de novo chromosome 2 cytogenetically visible deletions, one of them with an additional de novo deletion in chromosome 20p12.2p12.3. Patient I presents a 16.8?Mb deletion in 2q31.2q32.3 while patient II presents a smaller deletion of 7?Mb in 2q32.1q32.3, entirely contained within patient I deleted region, and a second 4?Mb deletion in Alagille syndrome region. Patient I clearly manifests symptoms associated with the 2q31.2q32.3 deletion syndrome, like the muscular phenotype and behavioral problems, while patient II phenotype is compatible with the 20p12 deletion since she manifests problems at the cardiac level, without significant dysmorphisms and an apparently normal psychomotor development.Whereas Alagille syndrome is a well characterized condition mainly caused by haploinsufficiency of JAG1 gene, with manifestations that can range from slight clinical findings to major symptoms in different domains, the 2q31.2q32.3 deletion syndrome is still being delineated. The occurrence of both imbalances in reported patient II would be expected to cause a more severe phenotype compared to the individual phenotype associated with each imbalance, which is not the case, since there are no manifestations due to the 2q32 deletion. This, together with the fact that patient I deleted region overlaps previously reported cases and patient II deletion is outside this common region, reinforces the existence of a critical region in 2q31.3q32.1, between 181 to 185?Mb, responsible for the clinical phenotype.
Molecular cytogenetic characterisation of a mosaic add(12)(p13.3) with an inv dup(3)(q26.31 → qter) detected in an autistic boy
Isabel M Carreira, Joana B Melo, Carlos Rodrigues, Liesbeth Backx, Joris Vermeesch, Anja Weise, Nadezda Kosyakova, Guiomar Oliveira, Eunice Matoso
Molecular Cytogenetics , 2009, DOI: 10.1186/1755-8166-2-16
Abstract: We present the results of the molecular cytogenetic characterization of an unbalanced mosaic karyotype consisting of mos 46,XY,add(12)(p13.3) [56]/46,XY [44] in a previously described 11 years old autistic boy, re-evaluated at adult age. The employment of fluorescence in situ hybridization (FISH) and multicolor banding (MCB) techniques identified the extra material on 12p to be derived from chromosome 3, defining the additional material on 12p as an inv dup(3)(qter → q26.3::q26.3 → qter). Subsequently, array-based comparative genomic hybridization (aCGH) confirmed the breakpoint at 3q26.31, defining the extra material with a length of 24.92 Mb to be between 174.37 and 199.29 Mb.This is the thirteenth reported case of inversion-duplication 3q, being the first one described as an inv dup translocated onto a non-homologous chromosome. The mosaic terminal inv dup(3q) observed could be the result of two proposed alternative mechanisms. The most striking feature of this case is the autistic behavior of the proband, a characteristic not shared by any other patient with tetrasomy for 3q26.31 → 3qter. The present work further illustrates the advantages of the use of an integrative cytogenetic strategy, composed both by conventional and molecular techniques, on providing powerful information for an accurate diagnosis. This report also highlights a chromosome region potentially involved in autistic disorders.According to the orientation of the duplicated segment, duplications may be classified either as tandem or inverted, being the last usually associated with deletion of the distal region of the duplicated chromosome [1]. The best studied cases of inverted duplications (inv dup) are the inv dup(8p) [2,3] and bisatellited inv dup(15) [4], which are usually non-mosaic. In contrast, mosaic inverted duplications are derived from different post-zygotic mechanisms for which various possible origins have been proposed [5-7]. There is also a particular subset of inv dup in which the
Sporulation of arbuscular mycorrhizal fungi using Tris-CHl buffer in addition to nutrient solutions
Silva, Fábio Sérgio B.;Yano-Melo, Adriana M.;Brand?o, Joana Angélica C.;Maia, Leonor C.;
Brazilian Journal of Microbiology , 2005, DOI: 10.1590/S1517-83822005000400004
Abstract: the production of inoculum is one of the hindrances in the large scale application of arbuscular mycorrhizal fungi (amf). the objective of this work was to evaluate the effect of nutrient solutions with or without tris-hcl buffer, on sporulation of amf. the experiment was carried out in a greenhouse, using a substrate with sand and vermiculite (1:1 v/v). fifty spores of gigaspora margarita, scutellospora heterogama, and glomus etunicatum were inoculated in sorghum vulgare (sorghum) or panicum miliaceum (fodder millet). the substrate received the following nutrient solutions: hoagland with 3 mm p (s1); long ashton ii with 15.9 mm p (s2) and hoagland with 20 mm p (s3), with or without 50 mm of tris-hcl buffer (ph 6.5); the control treatment, consisting of a soil + sand + vermiculite (2:1:1 v/v) substrate was irrigated with deionized water. ten weeks after the beginning of the experiment sporulation did not differ in treatments with sorghum. panicum miliaceum promoted higher sporulation of the amf than sorghum, and differences among treatments with nutrient solutions were observed. production of spores of g. margarita and s. heterogama increased significantly after addition of buffer in s1 and s2, while that of g. etunicatum was improved when the substrate was irrigated with s1 + buffer and s3 solutions. solution s1 + buffer benefited sporulation of the three fungi. however, as observed, each amf, host, and substrate system should be studied separately for establishment of the most favorable conditions for inoculum production.
Avalia??o de repertórios brasileiros em agricultura, ciência da informa??o e direito: uma análise de conteúdo
Moreiro González, José Ant?nio;Melo, Denise Gomes Pereira de;Garcia, Joana Coeli Ribeiro;Duarte, Emeide Nóbrega;Albuquerque, Maria Elizabeth B. C.;Melo, Maria de Lourdes de Arruda;Neves, Dulce Amélia de Brito;
Ciência da Informa??o , 1998, DOI: 10.1590/S0100-19651998000300006
Abstract: evaluation of content analysis which the brazilian repertories in agriculture (agrobase and the data base of agricultural and animal husbandry research), information science (lici), and law (brazilian bibliography of law) present. after identifying the antecedents, nature, potential users and type of product offered by each of these repertories, a percentage measure of the exhaustive breadth of their coverage was carried out. the tasks related to the evaluation of the indexing and abstracts were made based on a selection of twenty cases for each, which were compared by means of direct inspection with the corresponding originals. a questionnaire was also used to determine the documentary language and the criteria employed to carry out the analysis. special attention was given to an examination of the indexing and abstract presented in the original, as well as their depth and relevance, measuring where possible the index of consistency. the abstracts were studied in accordance with the transcription of the superstructure of the original and its technical quality, measuring the factors of legibility. the results were presented by means of comparative tables.
Prenatal Diagnosis of a Congenital Postaxial Longitudinal Limb Defect: A Case Report
Joana Pauleta,Maria Antonieta Melo,Luís Mendes Gra?a
Obstetrics and Gynecology International , 2010, DOI: 10.1155/2010/825639
Abstract: Introduction. Although congenital longitudinal fibular deficiency is one of the most common long bone deficiencies, there are few published cases of its prenatal diagnosis. Case report. A right longitudinal deficiency of the fibula associated with tibial shortening, foot equinovalgus, and absence of the fourth and fifth foot rays diagnosed at 22 weeks gestation is described. Sequential ultrasonographic surveillance was performed without obstetric complications. The anomaly was confirmed after birth, and conservative orthopaedic management was decided. Conclusion. Though rarely seen, postaxial longitudinal limb defect may be detected by ultrasound. The correct approach can only be decided after birth, when the functional impact of the anomaly can be fully evaluated. 1. Introduction Postaxial longitudinal defect is one of the most common congenital limb reduction defects. This entity includes a large spectrum of abnormalities that may range from severe hypoplasia to complete absence of the fibula and the 5th rays. It is a rare disorder, with an estimated prevalence of 5.7 to 20 cases per 1 million births [1]. Up to now, only few cases of prenatal diagnosis of isolated longitudinal deficiency of the fibula were reported [1–4]. 2. Case Report A 38-year-old healthy primigravida, with no familiar history of limb defects or exposure to teratogenic drugs, was referred to our ultrasound unit at 22 weeks gestation after the absence of the right fibula was diagnosed during the second trimester ultrasound examination. This diagnosis was confirmed in our department. Further assessment of the ipsilateral lower limb detected a discrete femur shortening (35?mm versus 37?mm of left femur, discrepancy of 5.4%), anteromedial bowing and tibial shortening (27.2?mm versus 33.6?mm of left tibia, discrepancy of 19%), see Figure 1, foot equinovalgus, and absence of the fourth and fifth foot rays and digits. All other long bones (humeri, ulnae, and radii) were symmetric and appropriated in length and configuration for gestational age, as were the hands. No other anomalies were detected, namely, craniosynostosis, omphalocele, renal displasia, neural tube defects, thoracoabdominal schisis, or facial dysmorphies. Amniocentesis revealed a normal female karyotype (46, XX). Fetal echocardiography was normal. Follow-up ultrasound examinations were carried out periodically until birth (Figure 2). Tibial discrepancy increased slightly with a difference of 13?mm (23.6%) at 34 weeks gestation. Figure 1: Ultrasound images showing absence of right fibula, bowing of right tibia (a), and
Porque estudar a morte? - Uma análise de oito anos
Tudela,Mariana; Cabrita,Joana Melo; Ribas,Maria José;
Revista Portuguesa de Clínica Geral , 2011,
Abstract: objectives: to analyze the causes of death and factors associated with the death of patients from one family practice. type of study: descriptive location: usf horizonte, matosinhos, portugal population: patients registered with one family doctor between 2000 and 2007. methods: the data were abstracted from clinic records using the piloto 32?, sam? and sape? electronic medical record systems. socio-demographic variables and factors related to the death of the patients were analyzed using an excel electronic spreadsheet. results: over an eight year period, 106 deaths were recorded giving a mortality rate of 8.7 deaths per 1000 patients per year. of these, 62.2% of the patients were male. the median age was 71.6 years. most were retired (79.2%) and most were married (50.9%) at the time of death. the place of death was known in 92.4% of cases. of these, 53.1% died in hospital and 40.8% died at home. limitation in activities of daily living (adl) was recorded among 58.4% of patients before their death. a primary caregiver was identified in 90.6% of cases. the caregiver was a family member in 55.7% of cases. a cause of death was unknown in 8.5% of cases. neoplasm was recorded as the cause of death in 47.7% of cases. discussion: these results reveal deficiencies in the clinical recording of information about the death of patients and in the reporting of deaths. the demographic characteristics of this population are similar to those found in other published studies of mortality in primary care from spain and israel. the distribution of care among family and non-family caregivers is similar. the major differences between this population and others lie in the causes of death. neoplasm was the most common cause of death and not cardiovascular disease, as has been found in other studies.
Syphilis at the Crossroad of Phylogenetics and Paleopathology
Fernando Lucas de Melo,Joana Carvalho Moreira de Mello,Ana Maria Fraga,Kelly Nunes,Sabine Eggers
PLOS Neglected Tropical Diseases , 2010, DOI: 10.1371/journal.pntd.0000575
Abstract: The origin of syphilis is still controversial. Different research avenues explore its fascinating history. Here we employed a new integrative approach, where paleopathology and molecular analyses are combined. As an exercise to test the validity of this approach we examined different hypotheses on the origin of syphilis and other human diseases caused by treponemes (treponematoses). Initially, we constructed a worldwide map containing all accessible reports on palaeopathological evidences of treponematoses before Columbus's return to Europe. Then, we selected the oldest ones to calibrate the time of the most recent common ancestor of Treponema pallidum subsp. pallidum, T. pallidum subsp. endemicum and T. pallidum subsp. pertenue in phylogenetic analyses with 21 genetic regions of different T. pallidum strains previously reported. Finally, we estimated the treponemes' evolutionary rate to test three scenarios: A) if treponematoses accompanied human evolution since Homo erectus; B) if venereal syphilis arose very recently from less virulent strains caught in the New World about 500 years ago, and C) if it emerged in the Americas between 16,500 and 5,000 years ago. Two of the resulting evolutionary rates were unlikely and do not explain the existent osseous evidence. Thus, treponematoses, as we know them today, did not emerge with H. erectus, nor did venereal syphilis appear only five centuries ago. However, considering 16,500 years before present (yBP) as the time of the first colonization of the Americas, and approximately 5,000 yBP as the oldest probable evidence of venereal syphilis in the world, we could not entirely reject hypothesis C. We confirm that syphilis seems to have emerged in this time span, since the resulting evolutionary rate is compatible with those observed in other bacteria. In contrast, if the claims of precolumbian venereal syphilis outside the Americas are taken into account, the place of origin remains unsolved. Finally, the endeavor of joining paleopathology and phylogenetics proved to be a fruitful and promising approach for the study of infectious diseases.
Evaluation of the dark pigment formation when mixing the sodium hypochlorite solution in different concentrations, with chlorhexidine gluconate 0.2%
Luis Eduardo Duarte IRALA,Tiago André Fontoura de MELO,Renata Grazziotin SOARES,Joana JUCHEM
RSBO , 2009,
Abstract: The aim of this study was to verify the dark pigment formation when mixing sodium hypochlorite solution in different concentrations, with chlorhexidine gluconate. Material and methods: 1 mL of sodium hypochlorite solution was mixed at concentrations of 0.5%, 1 to 1.5%, 2.5 to 3%, 4.5 to 5% with 1 mL of chlorhexidine at 0.2% in Petri dishes. After 5 minutes, the reading of the dishes was done. Results and conclusion: Through the results obtained, it can be observed that in all mixtures there was the formation of a dark pigment.
Page 1 /151568
Display every page Item

Copyright © 2008-2017 Open Access Library. All rights reserved.