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1.
Int J Surg Case Rep ; 122: 110086, 2024 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-39088969

RESUMO

INTRODUCTION AND IMPORTANCE: BIA-ALCL is a non-Hodgkin lymphoma occurring primarily in women with textured breast implants, typically presenting as late seroma. Diagnosis involves ultrasound-guided fine-needle aspiration or core needle biopsy, followed by cytologic and immunohistochemical evaluation. Positive results show CD30 cell expression and lack ALK expression. Treatment includes removing breast implants and the periprosthetic capsule. If the lymphoma has spread, en bloc capsulectomy, immunotherapy, and chemotherapy are required. Reconstruction can be done with smooth implants or autologous tissue. PRESENTATION OF CASE: We present here the case of a woman with a 12-year history of microtextured breast implants, without any cancer family background, who presented with peri-implant effusion in the left breast, which tested positive for BIA-ALCL at stage IA. The patient underwent breast implant removal with total capsulectomy and posterior successful autologous tissue reconstruction, demonstrating that outcomes can be satisfactory when properly treated. CLINICAL DISCUSSION: Paying attention to signs in women with breast implants, beyond imaging tests, can aid in the early diagnosis of BIA-ALCL and ensure a not aggressive treatment. This approach allows the reconstruction with autologous tissue without the need of further implants. CONCLUSION: BIA-ALCL is a rare disease, further studies about this lymphoma can help with early diagnosis and potential prevention.

2.
Genet Mol Biol ; 43(4): e20190359, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33231602

RESUMO

Breast cancer is the leading cause of death by cancer among women in less developed regions. In Colombia, few published studies have applied next-generation sequencing technologies to evaluate the genetic factors related to breast cancer. This study characterized the exome of three patients with breast cancer from southwestern Colombia to identify likely pathogenic or disease-related DNA sequence variants in tumor cells. For this, the exomes of three tumor tissue samples from patients with breast cancer were sequenced. The bioinformatics analysis identified two pathogenic variants in Fgfr4 and Nf1 genes, which are highly relevant for this type of cancer. Specifically, variant FGFR4-c.1162G>A predisposes individuals to a significantly accelerated progression of this pathology, while NF1-c.1915C>T negatively alters the encoded protein and should be further investigated to clarify the role of this variant in this neoplasia. Moreover, 27 novel likely pathogenic variants were found and 10 genes showed alterations of pathological interest. These results suggest that the novel variants reported here should be further studied to elucidate their role in breast cancer.

3.
Biomolecules ; 10(5)2020 04 30.
Artigo em Inglês | MEDLINE | ID: mdl-32365829

RESUMO

Cancer is one of the leading causes of mortality worldwide. Breast cancer is the most frequent cancer in women, and in recent years it has become a serious public health problem in Colombia. The development of large-scale omic techniques allows simultaneous analysis of all active genes in tumor cells versus normal cells, providing new ways to discover the drivers of malignant transformations. Whole exome sequencing (WES) was obtained to provide a deep view of the mutational genomic profile in a set of cancer samples from Southwest Colombian women. WES was performed on 52 tumor samples from patients diagnosed with invasive breast cancer, which in most cases (33/52) were ductal luminal breast carcinomas (IDC-LM-BRCA). Global variant call was calculated, and six different algorithms were applied to filter out false positives and identify pathogenic variants. To compare and expand the somatic tumor variants found in the Colombian cohort, exome mutations and genome-wide expression alterations were detected in a larger set of tumor samples of the same breast cancer subtype from TCGA (that included DNA-seq and RNA-seq data). Genes with significant changes in both the mutational and expression profiles were identified, providing a set of genes and mutations associated with the etiology of ductal luminal breast cancer. This set included 19 single mutations identified as tumor driver mutations in 17 genes. Some of the genes (ATM, ERBB3, ESR1, TP53) are well-known cancer genes, while others (CBLB, PRPF8) presented driver mutations that had not been reported before. In the case of the CBLB gene, several mutations were identified in TCGA IDC-LM-BRCA samples associated with overexpression of this gene and repression of tumor suppressive activity of TGF-ß pathway.


Assuntos
Neoplasias da Mama/genética , Carcinoma Ductal de Mama/genética , Exoma , Mutação , Adulto , Idoso , Neoplasias da Mama/metabolismo , Carcinoma Ductal de Mama/metabolismo , Feminino , Humanos , Pessoa de Meia-Idade , Oncogenes
4.
BMC Genomics ; 19(Suppl 8): 862, 2018 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-30537933

RESUMO

BACKGROUND: Repetitive DNA sequences (Repeats) are significant regions in the human genome that have a specific genomic distribution, structure, and several binding sites for genome architecture and function. In consequence, the possible configurations of Repeats in specific and dynamic regions like the gene promoters could define footprints for molecular mechanisms, pathways, and cell function beyond their density in the genome. Here we explored the distribution of Repeats in the upstream promoter region of the human coding genes with the aim to identify specific configurations, clusters and functional meaning of those elements. Our method includes structural descriptions, hierarchical clustering, pathway association, and functional enrichment analysis. RESULTS: We report here several configurations of Repeats in the upstream promoter region (UPR), which define 2729 patterns for the 80% of the human coding genes. There are 47 types of Repeats in these configurations, where the most frequent were Alu, Low_complexity, MIR, Simple_repeat, LINE/L2, LINE/L1, hAT-Charlie, and ERV1. The distribution, length, and the high frequency of Repeats in the UPR defines several patterns and clusters, where the minimum frequency of configuration among Repeats was higher than 0.7. We found those clusters associated with cellular pathways and ontologies; thus, it was plausible to determine groups of Repeats to specific functional insights, for example, pathways for Genetic Information Processing or Metabolism shows particular groups of Repeats with specific configurations. CONCLUSION: Based on these findings, we propose that specific configurations of repetitive elements describe frequent patterns in the upstream promoter for sets of human coding genes, which those correlated to specific and essential cell pathways and functions.


Assuntos
Algoritmos , Genoma Humano , Fases de Leitura Aberta , Regiões Promotoras Genéticas , Sequências Repetitivas de Ácido Nucleico , Análise por Conglomerados , Ontologia Genética , Humanos
5.
IEEE/ACM Trans Comput Biol Bioinform ; 15(5): 1611-1624, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-28749355

RESUMO

The multifractal analysis has allowed to quantify the genetic variability and non-linear stability along the human genome sequence. It has some implications in explaining several genetic diseases given by some chromosome abnormalities, among other genetic particularities. The multifractal analysis of a genome is carried out by dividing the complete DNA sequence in smaller fragments and calculating the generalized dimension spectrum of each fragment using the chaos game representation and the box-counting method. This is a time consuming process because it involves the processing of large data sets using floating-point representation. In order to reduce the computation time, we designed an application-specific processor, here called multifractal processor, which is based on our proposed hardware-oriented algorithm for calculating efficiently the generalized dimension spectrum of DNA sequences. The multifractal processor was implemented on a low-cost SoC-FPGA and was verified by processing a complete human genome. The execution time and numeric results of the Multifractal processor were compared with the results obtained from the software implementation executed in a 20-core workstation, achieving a speed up of 2.6x and an average error of 0.0003 percent.


Assuntos
Algoritmos , Fractais , Genômica/métodos , Análise de Sequência de DNA/métodos , DNA/análise , DNA/genética , Genoma Humano/genética , Humanos , Modelos Genéticos , Software
6.
BMC Bioinformatics ; 18(1): 163, 2017 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-28279163

RESUMO

BACKGROUND: Short linear motifs in host organisms proteins can be mimicked by viruses to create protein-protein interactions that disable or control metabolic pathways. Given that viral linear motif instances of host motif regular expressions can be found by chance, it is necessary to develop filtering methods of functional linear motifs. We conduct a systematic comparison of linear motifs filtering methods to develop a computational approach for predicting motif-mediated protein-protein interactions between human and the human immunodeficiency virus 1 (HIV-1). RESULTS: We implemented three filtering methods to obtain linear motif sets: 1) conserved in viral proteins (C), 2) located in disordered regions (D) and 3) rare or scarce in a set of randomized viral sequences (R). The sets C,D,R are united and intersected. The resulting sets are compared by the number of protein-protein interactions correctly inferred with them - with experimental validation. The comparison is done with HIV-1 sequences and interactions from the National Institute of Allergy and Infectious Diseases (NIAID). The number of correctly inferred interactions allows to rank the interactions by the sets used to deduce them: D∪R and C. The ordering of the sets is descending on the probability of capturing functional interactions. With respect to HIV-1, the sets C∪R, D∪R, C∪D∪R infer all known interactions between HIV1 and human proteins mediated by linear motifs. We found that the majority of conserved linear motifs in the virus are located in disordered regions. CONCLUSION: We have developed a method for predicting protein-protein interactions mediated by linear motifs between HIV-1 and human proteins. The method only use protein sequences as inputs. We can extend the software developed to any other eukaryotic virus and host in order to find and rank candidate interactions. In future works we will use it to explore possible viral attack mechanisms based on linear motif mimicry.


Assuntos
Genes Virais , HIV-1/genética , Interações Hospedeiro-Patógeno , Domínios e Motivos de Interação entre Proteínas , Motivos de Aminoácidos , DNA Viral/genética , Humanos , Reprodutibilidade dos Testes , Alinhamento de Sequência , Análise de Sequência de DNA , Software , Proteínas Virais/genética , Proteínas Virais/metabolismo
7.
Bioresour Technol ; 187: 346-353, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25863898

RESUMO

Fatty acid methyl esters (FAMEs, biodiesel) were produced from Nannochloropsis gaditana wet biomass (12% saponifiable lipids, SLs) by extraction of SLs and lipase catalyzed transesterification. Lipids were extracted by ethanol (96%)-hexane, and 31% pure SLs were obtained with 85% yield. When the lipids were degummed, SL purity increased to 95%. Novozym 435 was selected from four lipases tested. Both the lipidic composition and the use of t-butanol instead of hexane increased the reaction velocity and the conversion, since both decreased due to the adsorption of polar lipids on the lipase immobilization support. The best FAME yield (94.7%) was attained at a reaction time of 48h and using 10mL of t-butanol/g SL, 0.225gN435/g SL, 11:1 methanol/SL molar ratio and adding the methanol in three steps. In these conditions the FAME conversion decreased by 9.8% after three reaction cycles catalyzed by the same lipase batch.


Assuntos
Biocombustíveis/microbiologia , Ácidos Graxos/síntese química , Lipase/química , Metabolismo dos Lipídeos/fisiologia , Lipídeos/química , Estramenópilas/metabolismo , Ésteres , Eletricidade Estática
8.
J Biosci Bioeng ; 119(6): 706-11, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25575971

RESUMO

The aim of this work was to obtain biodiesel (methyl esters) from the saponifiable lipids (SLs) fraction of the microalga Nannochloropsis gaditana, whose biomass dry weight contains 12.1 wt% of these lipids. SLs were extracted from the microalga as free fatty acids (FFAs) for subsequent transformation to methyl esters (biodiesel) by enzymatic esterification. Extraction as FFAs rather than as SLs allows them to be obtained with higher purity. Microalgal FFAs were obtained by direct saponification of lipids in the biomass and subsequent extraction-purification with hexane. Esterification of FFAs with methanol was catalysed by lipase Novozym 435 from Candida antarctica. Stability studies of this lipase in the operational conditions showed that the esterification degree (ED) attained with the same batch of lipase remained constant over six reaction cycles (36 h total reaction time). The optimal conditions attained for 4 g of FFAs were 25°C, 200 rpm, methanol/FFA molar ratio of 1.5:1, Novozym 435/FFA ratio of 0.025:1 w/w and 4 h reaction time. In these conditions the ED attained was 92.6%, producing a biodiesel with 83 wt% purity from microalgal FFAs. Several experimental scales were tested (from 4 to 40 g FFAs), and in all cases similar EDs were obtained.


Assuntos
Biocombustíveis/provisão & distribuição , Esterificação , Ácidos Graxos não Esterificados/isolamento & purificação , Ácidos Graxos não Esterificados/metabolismo , Lipase/metabolismo , Microalgas/metabolismo , Óleos de Plantas/metabolismo , Biocatálise , Biocombustíveis/análise , Biomassa , Candida/enzimologia , Catálise , Estabilidade Enzimática , Enzimas Imobilizadas , Ésteres/síntese química , Ésteres/química , Ésteres/metabolismo , Proteínas Fúngicas , Hexanos/química , Metabolismo dos Lipídeos , Metanol/química , Microalgas/química , Óleos de Plantas/química , Temperatura , Fatores de Tempo
9.
IEEE J Biomed Health Inform ; 19(1): 37-43, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25486651

RESUMO

The progressive ageing of population has turned the mild cognitive impairment (MCI) into a prevalent disease suffered by elderly. Consequently, the spatial disorientation has become a significant problem for older people and their caregivers. The ambient-assisted living applications are offering location-based services for empowering elderly to go outside and encouraging a greater independence. Therefore, this paper describes the design and technical evaluation of a location-awareness service enabler aimed at supporting and managing probable wandering situations of a person with MCI. Through the presence capabilities of the IP multimedia subsystem (IMS) architecture, the service will alert patient's contacts if a hazardous situation is detected depending on his location. Furthermore, information about the older person's security areas has been included in the user profile managed by IMS. In doing so, the service enabler introduced contribute to "context-awareness" paradigm allowing the adaptation and personalization of services depending on user's context and specific conditions or preferences.


Assuntos
Disfunção Cognitiva/enfermagem , Sistemas de Informação Geográfica , Internet , Monitorização Ambulatorial/métodos , Sistemas de Identificação de Pacientes/métodos , Comportamento Errante , Software , Design de Software
10.
Bioresour Technol ; 169: 198-205, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25058294

RESUMO

Saponifiable lipids (SLs) were extracted with hexane from wet biomass (86 wt% water) of the microalga Nannochloropsis gaditana in order to transform them into fatty acid methyl esters (FAMEs, biodiesel). The influence of homogenization pressure on SL extraction yield at low temperature (20-22 °C) was studied. Homogenization at 1700 bar tripled the SL extraction yield. Two biomass batches with similar total lipid content but different lipidic compositions were used. Batch 1 contained fewer SLs (12.0 wt%) and neutral saponifiable lipids (NSLs, 7.9 wt%) than batch 2 (21.6 and 17.2 wt%, respectively). For this reason, and due to the selectivity of hexane toward NSLs, high SL yield (69.1 wt%) and purity (71.0 wt%) were obtained from batch 2. Moreover, this extract contains a small percentage of polyunsaturated fatty acids (16.9 wt%), thereby improving the biodiesel quality. Finally, up to 97.0% of extracted SLs were transformed to FAMEs by acid catalyzed transesterification.


Assuntos
Biocombustíveis/microbiologia , Biomassa , Biotecnologia/métodos , Lipídeos/isolamento & purificação , Microalgas/metabolismo , Água , Esterificação , Ácidos Graxos/análise , Cinética , Pressão
11.
PLoS One ; 8(3): e59488, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23536879

RESUMO

Environment-dependent genomic features have been defined for different metagenomes, whose genes and their associated processes are related to specific environments. Identification of ORFs and their functional categories are the most common methods for association between functional and environmental features. However, this analysis based on finding ORFs misses noncoding sequences and, therefore, some metagenome regulatory or structural information could be discarded. In this work we analyzed 23 whole metagenomes, including coding and noncoding sequences using the following sequence patterns: (G+C) content, Codon Usage (Cd), Trinucleotide Usage (Tn), and functional assignments for ORF prediction. Herein, we present evidence of a high proportion of noncoding sequences discarded in common similarity-based methods in metagenomics, and the kind of relevant information present in those. We found a high density of trinucleotide repeat sequences (TRS) in noncoding sequences, with a regulatory and adaptive function for metagenome communities. We present associations between trinucleotide values and gene function, where metagenome clustering correlate with microorganism adaptations and kinds of metagenomes. We propose here that noncoding sequences have relevant information to describe metagenomes that could be considered in a whole metagenome analysis in order to improve their organization, classification protocols, and their relation with the environment.


Assuntos
Microbiologia Ambiental , Metagenoma , Metagenômica , Análise por Conglomerados , Biologia Computacional/métodos , Genoma Bacteriano , Humanos , Anotação de Sequência Molecular , Fases de Leitura Aberta , RNA não Traduzido
12.
BMC Genomics ; 12: 506, 2011 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-21999602

RESUMO

BACKGROUND: Several studies have shown that genomes can be studied via a multifractal formalism. Recently, we used a multifractal approach to study the genetic information content of the Caenorhabditis elegans genome. Here we investigate the possibility that the human genome shows a similar behavior to that observed in the nematode. RESULTS: We report here multifractality in the human genome sequence. This behavior correlates strongly on the presence of Alu elements and to a lesser extent on CpG islands and (G+C) content. In contrast, no or low relationship was found for LINE, MIR, MER, LTRs elements and DNA regions poor in genetic information. Gene function, cluster of orthologous genes, metabolic pathways, and exons tended to increase their frequencies with ranges of multifractality and large gene families were located in genomic regions with varied multifractality. Additionally, a multifractal map and classification for human chromosomes are proposed. CONCLUSIONS: Based on these findings, we propose a descriptive non-linear model for the structure of the human genome, with some biological implications. This model reveals 1) a multifractal regionalization where many regions coexist that are far from equilibrium and 2) this non-linear organization has significant molecular and medical genetic implications for understanding the role of Alu elements in genome stability and structure of the human genome. Given the role of Alu sequences in gene regulation, genetic diseases, human genetic diversity, adaptation and phylogenetic analyses, these quantifications are especially useful.


Assuntos
Fractais , Genoma Humano , Elementos Alu , Composição de Bases , Mapeamento Cromossômico , Cromossomos Humanos/genética , Ilhas de CpG , Bases de Dados Genéticas , Análise Discriminante , Humanos , Modelos Genéticos , Família Multigênica , Análise de Sequência de DNA
14.
Photosynth Res ; 75(3): 211-21, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-16228602

RESUMO

A comparison of 8 cyanobacterial genomes reveals that there are 181 shared genes that do not have obvious orthologs in other bacteria. These signature genes define aspects of the genotype that are uniquely cyanobacterial. Approximately 25% of these genes have been associated with some function. These signature genes may or may not be involved in photosynthesis but likely they will be in many cases. In addition, several examples of widely conserved gene order involving two or more signature genes were observed. This suggests there may be regulatory processes that have been preserved throughout the long history of the cyanobacterial phenotype. The results presented here will be especially useful because they identify which of the many genes of unassigned function are likely to be of the greatest interest.

15.
Int. j. lepr. other mycobact. dis ; 67(4): 392-402, Dec., 1999. ilus, tab, graf
Artigo em Inglês | Sec. Est. Saúde SP, HANSEN, Hanseníase, SESSP-ILSLACERVO, Sec. Est. Saúde SP | ID: biblio-1226900

RESUMO

A polyclonal serum sample from a lepromatous leprosy (LL) patient, which presented a specific recognition pattern for leprosin, was used to screen a Mycobacterium leprae genomic library constructed with DNA isolated from human lepromas. One clone, designated ML4-1, which expressed a specific antigenic determinant of M. leprae as part of a beta-galactosidase fusion protein, was isolated. The 1.932 bp M. leprae-derived genomic fragment was sequenced, and it had an incomplete open-reading frame shown to code for a 644 amino-acid polypeptide (72.3 kDa). Some partial nucleotide homology to the M. tuberculosis MTCY9C4 cosmid and the M. leprae B1913 cosmid were found. Southern blot assays using the 584 bp Eco RI-Bam HI fragment excised from the ML4-1 clone revealed that this sequence is present only in the M. leprae genome and not in the 24 different mycobacterial DNA tested. Two oligonucleotides based on the genomic sequence were also synthesized and used as amplifiers for a polymerase chain reaction (PCR) test, giving a positive signal exclusively in M. leprae DNA. Furthermore, 32 sequential synthetic peptides, 20 amino-acids long, spanning the entire protein corresponding to the hypothetical ML4-1 clone sequence, were synthesized and evaluated by ELISA. A peptide included in the 221-240 region was significantly recognized by either lepromatous leprosy or healthy tuberculosis contact patient sera. Thus, PCR amplification of this fragment, along with the recognition of its protein sequence by leprosy patient sera, could be a useful tool for a potential diagnostic method in the detection of M. leprae infection in the future.


Assuntos
Hanseníase , Hanseníase/genética , Mycobacterium leprae/genética , Mycobacterium leprae/isolamento & purificação
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