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1.
Methods Mol Biol ; 2170: 117-124, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32797454

RESUMO

MicroRNAs (miRNAs) are small RNAs, that bind to mRNA targets and regulate their translation. Functional study of miRNAs and exploration of their utility as disease markers require miRNA extraction from biological samples, which contain large amounts of interfering compounds for downstream RNA identification and quantification. The most common extraction methods employ either silica columns or TRIzol reagent, but these approaches afford low recovery for small RNAs, possibly due to their short strand lengths. Here, we describe the fabrication of titanium dioxide nanofibers and the optimal extraction conditions to improve miRNA recovery from biological buffers, cell lysate, and serum.


Assuntos
Nanofibras/química , Titânio/química , Biomarcadores , Humanos , MicroRNAs/química
2.
J Chromatogr A ; 1631: 461535, 2020 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-32956878

RESUMO

Accurate quantitation of low dose, multi-active dissolution samples poses unique challenges in the pharmaceutical industry, often resulting in separate HPLC methods for each active or the use of multiple detectors for increased sensitivity. In this study, we report a fast, isocratic HPLC method utilizing only UV detection for dissolution testing of low dose desogestrel and ethinylestradiol tablets. Rapid separation is completed in 5 min using isocratic elution at a flow rate of 0.45 mL/min, with a column temperature at 30 °C, an injection volume of 50 µL and the detection wavelength at 200 nm. After extensive method development and optimization, the cyano stationary phase was used to overcome the large difference in hydrophobicity for desogestrel and ethinylestradiol, providing balanced retention for both analytes under isocratic elution. Chromatography modeling software was used to provide a rapid analysis of multiple columns and chromatography conditions. The optimized method boasts fast and efficient separation through use of a short, small I.D. column and a large injection volume of dissolution solution to achieve high sensitivity. The stable baseline from an isocratic separation allows low detection wavelengths to be used, resulting in accurate and precise quantitation of both desogestrel and ethinylestradiol. The method has been successfully validated for specificity, linearity, accuracy and precision in the range of 75 - 600 ng/mL for desogestrel and 10 - 80 ng/mL for ethinylestradiol using both HPLC and UHPLC systems. The method robustness was characterized using a design of experiment approach, and the operational design region of the method was established.


Assuntos
Desogestrel , Etinilestradiol , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida , Solubilidade , Comprimidos
3.
Nucleic Acids Res ; 47(22): 11527-11537, 2019 12 16.
Artigo em Inglês | MEDLINE | ID: mdl-31733056

RESUMO

DNA methyltransferases (DNMTs) are enzymes responsible for establishing and maintaining DNA methylation in cells. DNMT inhibition is actively pursued in cancer treatment, dominantly through the formation of irreversible covalent complexes between small molecular compounds and DNMTs that suffers from low efficacy and high cytotoxicity, as well as no selectivity towards different DNMTs. Herein, we discover aptamers against the maintenance DNA methyltransferase, DNMT1, by coupling Asymmetrical Flow Field-Flow Fractionation (AF4) with Systematic Evolution of Ligands by EXponential enrichment (SELEX). One of the identified aptamers, Apt. #9, contains a stem-loop structure, and can displace the hemi-methylated DNA duplex, the native substrate of DNMT1, off the protein on sub-micromolar scale, leading for effective enzymatic inhibition. Apt. #9 shows no inhibition nor binding activity towards two de novo DNMTs, DNMT3A and DNMT3B. Intriguingly, it can enter cancer cells with over-expression of DNMT1, colocalize with DNMT1 inside the nuclei, and inhibit the activity of DNMT1 in cells. This study opens the possibility of exploring the aptameric DNMT inhibitors being a new cancer therapeutic approach, by modulating DNMT activity selectively through reversible interaction. The aptamers could also be valuable tools for study of the functions of DNMTs and the related epigenetic mechanisms.


Assuntos
Aptâmeros de Nucleotídeos/química , DNA (Citosina-5-)-Metiltransferase 1/antagonistas & inibidores , Metilação de DNA/genética , Neoplasias/genética , Aptâmeros de Nucleotídeos/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Desoxicitidina/análogos & derivados , Desoxicitidina/análise , Epigênese Genética/genética , Células HEK293 , Células HeLa , Humanos , Neoplasias/tratamento farmacológico
4.
J Minim Invasive Gynecol ; 26(6): 1104-1109, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30414998

RESUMO

STUDY OBJECTIVE: To determine the surgical time, suture time, presence of postoperative dyspareunia, and complications that occur after closing the vaginal cuff with a barbed suture compared with conventional suture. DESIGN: A randomized, controlled clinical trial (Canadian Task Force classification I). SETTING: Private gynecologic clinic in Medellin, Colombia. PATIENTS: One hundred fifty women who underwent total laparoscopic hysterectomy for benign pathology. INTERVENTIONS: The patients underwent total laparoscopic hysterectomy with intracorporeal closure of the vaginal cuff and were randomized to 2 groups, 1 using a barbed suture (V-Loc 90; Medtronic/Covidien, New Haven, CT) and 1 using polyglactin 910 (coated Vicryl suture; Ethicon/Johnson & Johnson, New Brunswick, NJ). MEASUREMENTS AND MAIN RESULTS: The total operative time, closing time of the vaginal vault, presence of complications in the cuff, and incidence of postoperative dyspareunia were recorded. The patients were evaluated at a postoperative office visit 2 weeks after the procedure and by telephone interview at 24 weeks. Seventy-five patients were included in the barbed suture group and 75 patients in the polyglactin 910 group. The average time to complete the suture of the vaginal cuff was 12.01 minutes (± 5.37 standard deviation) for the barbed suture group versus 13.49 minutes (± 6.48) in the polyglactin 910 group (95% confidence interval, -.44 to 3.4; p = .130). Blood loss was 31.56 ± 22.93 mL in the barbed suture group versus 30.82 ± 21.75 mL in the polyglactin 910 group (95% confidence interval, -7.95 to 6.47; p = .840). The frequency of postoperative events such as hematoma, cellulitis, cuff dehiscence, fever, emergency consultation, and hospitalization was not statistically significant between groups. No statistically significant difference was found regarding deep dyspareunia at 24 postoperative weeks. CONCLUSION: No differences were found in surgical time or frequency of adverse events when comparing patients after vaginal cuff closure with barbed suture versus polyglactin 910.


Assuntos
Histerectomia/métodos , Técnicas de Sutura , Doenças Uterinas/cirurgia , Vagina/cirurgia , Técnicas de Fechamento de Ferimentos , Adulto , Colômbia/epidemiologia , Dispareunia/epidemiologia , Dispareunia/etiologia , Feminino , Humanos , Histerectomia/efeitos adversos , Histerectomia/estatística & dados numéricos , Incidência , Laparoscopia/efeitos adversos , Laparoscopia/métodos , Laparoscopia/estatística & dados numéricos , Pessoa de Meia-Idade , Duração da Cirurgia , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Período Pós-Operatório , Estruturas Criadas Cirurgicamente/patologia , Técnicas de Sutura/efeitos adversos , Técnicas de Sutura/estatística & dados numéricos , Suturas/efeitos adversos , Resultado do Tratamento , Doenças Uterinas/epidemiologia , Vagina/patologia , Técnicas de Fechamento de Ferimentos/efeitos adversos , Técnicas de Fechamento de Ferimentos/estatística & dados numéricos
5.
Trends Analyt Chem ; 117: 242-262, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32292220

RESUMO

Non-coding RNAs (ncRNAs) participate in regulation of gene expression, and are highly relevant to pathological development. They are found to be stably present in diverse body fluids, including those in the circulatory system, which can be sampled non-invasively for clinical tests. Thus, circulating ncRNAs have great potential to be disease biomarkers. However, tremendous efforts are desired to discover and utilize ncRNAs as biomarkers in clinical diagnosis, calling for technological advancement in analysis of circulating ncRNAs in biospecimens. Hence, this review summarizes the recent developments in this area, highlighting the works devoted to cancer diagnosis and prognosis. Three main directions are focused: 1) Extraction and purification of ncRNAs from body fluids; 2) Quantification of the purified circulating ncRNAs; and 3) Microfluidic platforms for integration of both steps to enable point-of-care diagnostics. These technologies have laid a solid foundation to move forward the applications of circulating ncRNAs in disease diagnosis and cure.

6.
Mitochondrial DNA B Resour ; 4(2): 4031-4032, 2019 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-33366303

RESUMO

Genomic analysis of the invasive marine snail Batillaria attramentaria from Elkhorn Slough, Moss Landing, California, USA using 150 bp paired-end Illumina sequences resulted in the assembly of its complete mitogenome. The mitogenome is 16,095 bp in length and contains 2 rRNA, 13 protein-coding, and 22 tRNA genes (GenBank Accession MN557850). Gene content and organization of B. attramentaria are identical to the Turritellidae and Pachychilidae. The phylogenetic analysis of B. attramentaria resolves it in a fully supported clade with these same two families in the superfamily Cerithioidea. Nucleotide BLAST searches of the Elkhorn Slough cox1 gene of B. attramentaria yielded identical sequences from invasive populations from California and British Columbia, and native populations from northeastern and central Japan. These data show that mitogenome sequencing is a useful tool for studying the classification and phylogenetic history Cerithioidea.

7.
Rev. colomb. cienc. pecu ; 31(4): 256-266, oct.-dic. 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-985479

RESUMO

Abstract Background: Genetic association studies have been increasingly used in cattle breeding programs. However, inconsistent results -such as positive, negative, or absence of association- across studies restrain reproducibility and proper implementation, propitiating the occurrence of bias. Objective: To identify and classify potential sources of bias and determine possible strategies to avoid it in genetic association studies in cattle. Source of bias in genetic association studies: Genetic and genomic sources of bias include effects associated with the gene loci governing expression. Sampling-related and statistical biases are related with factors such as stratification and database size. Strategies to correct bias in genetic association studies: Correction strategies differ in nature. Genetic and genomic strategies are based on determining the appropriate approach to obtain and report the genetic information. Sampling-related and statistical strategies are based on grouping individuals with certain traits that lead to a reduction in heterogeneity. Conclusion: It is necessary to consider the methodology used in previous studies to establish a hierarchy of sources of bias and facilitate decisions on the use of tools to reduce inconsistencies in the results of future studies.


Resumen Antecedentes: Los estudios de asociación genética son cada vez más usados en los programas de mejoramiento genético. Sin embargo, resultados inconsistentes de los estudios -como positivos, negativos o ausencia de asociación- restringen la reproducibilidad y su aplicación adecuada, propiciando la aparición de sesgos. Objetivo: Identificar y clasificar las fuentes potenciales de sesgo y determinar posibles estrategias para evitarlo en estudios de asociación genética en ganado. Fuentes de sesgo en estudios de asociación genética: Las fuentes genéticas y genómicas de sesgo incluyen los efectos asociados con la expresión que gobierna los loci. Los sesgos estadísticos y de muestreo están relacionados con factores como la estratificación y el tamaño de la base de datos. Estrategias para corregir sesgos en estudios de asociación genética: Las estrategias de corrección difieren en naturaleza. Las estrategias genéticas y genómicas se basan en determinar el enfoque apropiado para obtener la información genética. Las estrategias estadísticas y relacionadas con el muestreo se basan en la agrupación de individuos con ciertos rasgos que conducen a una reducción de la heterogeneidad. Conclusión. Se deben considerar las metodologías utilizadas en estudios previos para jerarquizar las fuentes de sesgo y facilitar las decisiones sobre el uso de herramientas para reducir inconsistencias en resultados futuros.


Resumo Antecedentes: Nos programas de criação de bovinos, os estudos de associação genética têm sido cada vez mais utilizados. No entanto, resultados inconsistentes, como positivos, negativos ou ausência de associação entre os estudos, restringem a reprodutibilidade e sua adequada implementação, propiciando o aparecimento de viés. Objetivo: Identificar e classificar potenciais fontes de viés e determinar estratégias possíveis para evitá-lo nos estudos de associação genética em bovinos. Fonte de viés em estudos de associação genética: Fontes genéticas e genômicas do viés incluem os efeitos associados aos genes que relacionam a expressão. Os vícios estatísticos e de amostragem estão relacionados a fatores como a estratificação e o tamanho do banco de dados. Estratégias para corrigir os viéses nos estudos de associação genética: As estratégias de correção diferem na natureza. As estratégias genéticas e genômicas são baseadas na determinação da abordagem apropriada para obter e relatar a informação genética. As estratégias estatísticas e de amostragem baseiam-se no agrupamento de indivíduos com certos traços que levam a uma redução na heterogeneidade. Conclusão: É necessário considerar a metodologia utilizada em estudos anteriores para estabelecer uma hierarquia de fontes de viés e facilitar decisões sobre o uso de ferramentas para reduzir inconsistências nos resultados de estudos futuros.

8.
Sensors (Basel) ; 18(4)2018 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-29614003

RESUMO

The high incidence of Diabetes Mellitus in low-income regions has promoted the development of low-cost alternatives to replace blood-based procedures. In this work, we present a bienzymatic paper-based sensor suitable for the naked-eye detection of glucose in saliva samples. The sensor was obtained by a stamping procedure and modified with chitosan to improve the colorimetric readout. The bienzymatic reaction of GOx-HRP coupled with 2,4,6-tribromo-3-hydroxy benzoic acid was applied for the detection of glucose within a range from 0 to 180 mgdL-1 in buffer and artificial saliva solutions. The visual readout was perceived by the naked eye and registered with an office scanner to evaluate the analytical performance. The results showed a limit of detection of 0.37 mgdL-1 (S/N = 3) with an R.S.D. of 1.69% and a linear range from 1 to 22.5 mgdL-1 with an R² of 0.99235. The analysis of human saliva samples was performed without pre-processing, achieving recoveries from 92 to 114%. The naked-eye detection was evaluated under two different light settings, showing average recoveries of 108.58 and 90.65% for standard and low illumination. The proposed device showed potential for easy-to-use, sensitive, low-cost, fast, and device-free detection of salivary glucose suitable for untrained personnel operation and limited facilities.


Assuntos
Saliva , Colorimetria , Olho , Glucose , Humanos , Papel , Visão Ocular
9.
Anal Bioanal Chem ; 410(3): 1053-1060, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29030663

RESUMO

MicroRNAs (miRNAs) are small RNAs that bind to mRNA targets and regulate their translation. A functional study of miRNAs and exploration of their utility as disease markers require miRNA extraction from biological samples, which contain large amounts of interfering compounds for downstream RNA identification and quantification. The most common extraction methods employ silica columns or the TRIzol reagent but give out low recovery for small RNAs probably due to their short strand lengths. Herein, we fabricated the titanium dioxide nanofibers using electrospinning to facilitate miRNA extraction and developed the optimal buffer conditions to improve miRNA recovery from biological matrices of cell lysate and serum. We found that our TiO2 fibers could obtain a recovery of 18.0 ± 3.6% for miRNA fibers while carrying out the extraction in the more complex medium of cell lysate, much higher than the 0.02 ± 0.0001% recovery from the commercial kit. The much improved extraction of miRNAs from our fibers could be originated from the strong coordination between TiO2 and RNA's phosphate backbone. In addition, the binding, washing, and elution buffers judiciously developed in the present study can achieve selective extraction of small RNA shorter than 500 nucleotides in length. Our results demonstrate that TiO2 nanofibers can work as a valuable tool for extraction of miRNAs from biological samples with high recovery. Graphical abstract Schematic for extraction of small RNAs using TiO2 nanofibers.


Assuntos
MicroRNAs/isolamento & purificação , Nanofibras/química , Extração em Fase Sólida/métodos , Titânio/química , Adsorção , Soluções Tampão , Linhagem Celular Tumoral , Técnicas Eletroquímicas , Humanos , MicroRNAs/sangue , Nanofibras/ultraestrutura
10.
G3 (Bethesda) ; 7(8): 2439-2460, 2017 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-28667019

RESUMO

The discordance between genome size and the complexity of eukaryotes can partly be attributed to differences in repeat density. The Muller F element (∼5.2 Mb) is the smallest chromosome in Drosophila melanogaster, but it is substantially larger (>18.7 Mb) in D. ananassae To identify the major contributors to the expansion of the F element and to assess their impact, we improved the genome sequence and annotated the genes in a 1.4-Mb region of the D. ananassae F element, and a 1.7-Mb region from the D element for comparison. We find that transposons (particularly LTR and LINE retrotransposons) are major contributors to this expansion (78.6%), while Wolbachia sequences integrated into the D. ananassae genome are minor contributors (0.02%). Both D. melanogaster and D. ananassae F-element genes exhibit distinct characteristics compared to D-element genes (e.g., larger coding spans, larger introns, more coding exons, and lower codon bias), but these differences are exaggerated in D. ananassae Compared to D. melanogaster, the codon bias observed in D. ananassae F-element genes can primarily be attributed to mutational biases instead of selection. The 5' ends of F-element genes in both species are enriched in dimethylation of lysine 4 on histone 3 (H3K4me2), while the coding spans are enriched in H3K9me2. Despite differences in repeat density and gene characteristics, D. ananassae F-element genes show a similar range of expression levels compared to genes in euchromatic domains. This study improves our understanding of how transposons can affect genome size and how genes can function within highly repetitive domains.


Assuntos
Cromossomos/genética , Drosophila/genética , Retroelementos/genética , Animais , Composição de Bases/genética , Sequência de Bases , Códon/genética , Feminino , Perfilação da Expressão Gênica , Genes de Insetos , Histonas/metabolismo , Processamento de Proteína Pós-Traducional/genética , Wolbachia/genética
11.
Methods Mol Biol ; 1509: 161-168, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-27826926

RESUMO

MicroRNAs (miRNAs) are stably present in circulatory systems. They are bound to various carriers like proteins, lipoprotein particles, and exosomes. Investigating the process of miRNA distribution among these carriers will help improve our understanding of their functions in the extracellular environment and their potential relationship with diseases. Here, we describe how to obtain the distribution profiles of circulating miRNAs by separation of different miRNA carriers in human serum with asymmetrical flow field flow fractionation (AF4), and detection of the miRNAs in the eluted fractions that enrich particular types of carriers with RT-qPCR.


Assuntos
Biomarcadores Tumorais/isolamento & purificação , MicroRNA Circulante/isolamento & purificação , Biomarcadores Tumorais/sangue , Biomarcadores Tumorais/genética , Cromatografia Líquida/métodos , MicroRNA Circulante/sangue , MicroRNA Circulante/genética , Humanos , Reação em Cadeia da Polimerase Via Transcriptase Reversa
12.
Bol Asoc Med P R ; 108(2): 11-5, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-29164844

RESUMO

The subclavian artery pseudoaneurysm is a rare entity with only few cases re- ported in the literature. Most injuries were related to iatrogenic manipulation with catheters for canalization of central lines in the hospital setting. In rare cases, this injury has been described secondary to a blunt trauma and motor vehicle accidents with traumatic injury to the subclavian artery caused by seatbelt use. We report an unusual case presentation of subclavian artery pseudoaneurysm.


Assuntos
Falso Aneurisma/diagnóstico , Transtornos de Deglutição/etiologia , Dispneia/etiologia , Rouquidão/etiologia , Adulto , Falso Aneurisma/complicações , Humanos , Masculino , Artéria Subclávia/lesões
13.
Bisturi (S Juan) ; 2016: 12-16, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-29238632

RESUMO

Prolymphocytic leukemias (PLLs) are rare mature lymphoid disorders of B- and T-cell subtypes with distinct features and an aggressive clinical course. PLL represents only 2% of all mature lymphocytic leukemias in adults. T-PLL represents 20% of all PLLs cases. T-cell prolymphocytic leukemia (T-PLL) is more rare and more rapidly progressive and aggressive than B-PLL; it is generally resistant to conventional chemotherapy, and historically the median survival has been about 7 months. Clinicians will often only see a case of T-PLL once every 5 to 10 years, which makes recognition of the disorder difficult. The prognosis is poor and there is no curative therapy. We report a 77-year-old male patient with de novo T-PLL presenting with WBC count of 1,115,000. We will discuss the clinical, morphologic, immunophenotypic and cytogenetic features of this rare entity. A distinctive hematologic aspect of T-PLL is a rapidly rising white blood cell count with a doubling time of weeks to months. The key morphologic feature in the diagnosis of T-PLL is a population of more than 55% prolymphocytes in the peripheral blood. The diagnosis can be made on peripheral blood by flow cytometry where a monoclonal lymphocyte population will show positivity for T-cell markers. T-PLL is characterized by complex chromosomal abnormalities, which suggests that chromosomal aberrations might occur progressively during the course of the disease, thus explaining the aggressive nature of this condition. The main challenge as a clinician treating T-PLL is to deliver long-term disease-free survival. The most important predictor of outcome is response to alemtuzumab therapy (Campath). Knowledge of the disrupted pathways and mechanisms underlying activation and proliferation in T-PLL has raised the possibility of developing future and promising treatment approach that targets these pathways and signals by the use of future molecule inhibitors. T-PLL is a rare disease and careful attention should be given to correctly diagnose this T-cell leukemia. Physicians should be aware of this unusual entity. With the advent of alemtuzumab, although much progress has been made in the treatment of this disease, autologous or allogeneic hematologic stem cell transplant (HSCT) still remains the only hope for cure.

14.
Bol Asoc Med P R ; 107(1): 45-8, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26035985

RESUMO

Splenic artery aneurysms (SAA) are a rare life threatening clinical diagnosis. We present a case of a young Hispanic woman with an aneurysm of the middle branch of the splenic artery and active leakage. The defect was embolized with complete resolution of the retroperitoneal bleeding. Physicians should be aware of this rare entity especially when female patients presents complainiing of severe epigastric pain with associated hypovolemic shock.


Assuntos
Aneurisma Roto/complicações , Aneurisma/complicações , Hemorragia/etiologia , Artéria Esplênica/patologia , Feminino , Hispânico ou Latino , Humanos , Espaço Retroperitoneal/patologia , Adulto Jovem
15.
Bol Asoc Med P R ; 107(3): 9-12, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26742189

RESUMO

Paroxysmal nocturnal hemoglobinuria (PNH) is a non-malignant, acquired clonal hematopoietic stem cell disease that can present with bone marrow failure, hemolytic anemia, smooth muscle dystonias, and thrombosis. We present a case of a 32 year-old-female, G2P2A0 with no past medical history of any systemic illnesses who refers approximately 2 months of progressively worsening constant heartburn with associated abdominal discomfort. CBC showed leukopenia (WBC 2.9 x 103 /µL) with neutropenia (segmented neutrophils 48%), macrocytic anemia (Hgb 6.1 g/dL, hematocrit 20%, MCV,113 fL) and thrombocytopenia (platelet count 59 x 109/L). Abdomino-pelvic CT scan revealed a superior mesenterc vein thrombosis, which was treated initially with low-molecular-weight heparih for full anticoagulation. Peripheral blood flow cytometry assays revealed diminished expression of CD55 and CD59 on the erythrocytes, granulocytes and monocytes.' Paroxysmal nocturnal hemoglobinuria is a rare, clonal, hematopoietic stem-cell disorder whose manifestations are almost entirely explained by complement-mediated intravascular hemolysis. The natural history of PNH is highly variable, ranging from indolent to life-threatening. The median survival is 10 to 15 years, but with a wide range. Thrombosis is the leading cause of death, but others may die of complications of bone marrow failure, renal failure, myelodysplastic syndrome, and leukemia. Anticoagulation is only partially effective in preventing thrombosis in PNH; thus, thrombosis is an absolute indication for initiating treatment with Eculizumab. Nevertheless, bone marrow transplantation (BMT) is still the only curative therapy for PNH but is associated with significant morbidity and mortality.


Assuntos
Azia/etiologia , Hemoglobinúria Paroxística/diagnóstico , Dor Abdominal/etiologia , Adulto , Anticorpos Monoclonais Humanizados/uso terapêutico , Anticoagulantes/uso terapêutico , Medula Óssea/patologia , Fadiga/etiologia , Feminino , Glicosilfosfatidilinositóis/deficiência , Hemoglobinúria/etiologia , Hemoglobinúria Paroxística/complicações , Heparina de Baixo Peso Molecular/uso terapêutico , Humanos , Isquemia Mesentérica/diagnóstico por imagem , Isquemia Mesentérica/tratamento farmacológico , Isquemia Mesentérica/etiologia , Pancitopenia/etiologia , Tomografia Computadorizada por Raios X , Varfarina/uso terapêutico
16.
Anal Chem ; 86(18): 9343-9, 2014 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-25191694

RESUMO

Circulating microRNAs (miRNAs) are potential biomarkers useful in cancer diagnosis. They have been found to be bound to various carriers like proteins, lipoprotein particles, and exosomes. It is likely that only miRNAs in particular carriers, but not the overall quantity, are directly related to cancer development. Herein, we developed a method for rapid separation of different miRNA carriers in serum using asymmetrical flow field flow fractionation (AF4). Sera from two healthy individuals (control) or from two cancer patients (case) were fractionated. Six fractions enriching different types of miRNA carriers, such as the lipoprotein particles and exosomes, were collected. The quantities of eight selected miRNAs in each fraction were obtained by RT-qPCR to yield their distribution profiles among the carriers. Larger changes in miRNA quantity between the control and the case were detected in the fractionated results compared to the sum values. Statistical analysis on the distribution profiles also proved that, the quantities of 4 miRNAs within particular fractions showed significant difference between the controls and the cases. On the contrary, if the overall quantity of the miRNA was subject to the same statistical analysis, only 2 miRNAs exhibited significant difference. Moreover, principle component analysis revealed good separation between the controls and the cases with the fractionated miRNA amounts. All in all, we have demonstrated that, our method enables comprehensive screening of the distribution of circulating miRNAs in the carriers. The obtained distribution profile enlarges the miRNA expression difference between healthy individuals and cancer patients, facilitating the discovery of specific miRNA biomarkers for cancer diagnosis.


Assuntos
MicroRNAs/sangue , Reação em Cadeia da Polimerase em Tempo Real , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/genética , Exossomos/metabolismo , Feminino , Fracionamento por Campo e Fluxo , Perfilação da Expressão Gênica , Humanos , Lipoproteínas/isolamento & purificação , Lipoproteínas/metabolismo , MicroRNAs/isolamento & purificação , Análise de Componente Principal , Ultrafiltração
17.
J Chromatogr A ; 1358: 217-24, 2014 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-25064532

RESUMO

Tools capable of measuring binding affinities as well as amenable to downstream sequencing analysis are needed for study of DNA-protein interaction, particularly in discovery of new DNA sequences with affinity to diverse targets. Asymmetrical flow field-flow fractionation (AF4) is an open-channel separation technique that eliminates interference from column packing to the non-covalently bound complex and could potentially be applied for study of macromolecular interaction. The recovery and elution behaviors of the poly(dA)n strand and aptamers in AF4 were investigated. Good recovery of ssDNAs was achieved by judicious selection of the channel membrane with consideration of the membrane pore diameter and the radius of gyration (Rg) of the ssDNA, which was obtained with the aid of a Molecular Dynamics tool. The Rg values were also used to assess the folding situation of aptamers based on their migration times in AF4. The interactions between two ssDNA aptamers and their respective protein components were investigated. Using AF4, near-baseline resolution between the free and protein-bound aptamer fractions could be obtained. With this information, dissociation constants of ∼16nM and ∼57nM were obtained for an IgE aptamer and a streptavidin aptamer, respectively. In addition, free and protein-bound IgE aptamer was extracted from the AF4 eluate and amplified, illustrating the potential of AF4 in screening ssDNAs with high affinity to targets. Our results demonstrate that AF4 is an effective tool holding several advantages over the existing techniques and should be useful for study of diverse macromolecular interaction systems.


Assuntos
DNA de Cadeia Simples/química , Proteínas de Ligação a DNA/química , Fracionamento por Campo e Fluxo/métodos , Aptâmeros de Peptídeos/química , Sequência de Bases , DNA de Cadeia Simples/isolamento & purificação , Simulação de Dinâmica Molecular , Ligação Proteica , Estreptavidina/química
18.
Bol Asoc Med P R ; 106(2): 42-5, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25065051

RESUMO

Madelung's disease is an extremely rare disorder of unknown etiology characterized by multiple, non-encapsulated, infiltrative lipomas located symmetrically on the trunk, neck, and proximal parts of the limbs. Approximately 200 patients have been reported in the medical literature. In this case report we present an extremely unusual case of multiple symmetric lipomatosis compatible with Madelung's disease.


Assuntos
Lipomatose Simétrica Múltipla/diagnóstico , Humanos , Masculino , Pessoa de Meia-Idade
19.
Bol Asoc Med P R ; 106(4): 43-5, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-26148400

RESUMO

Kaposi's sarcoma is a rare malignancy requiring infection with human Herpes virus for development. We report a case of a 76-year-old immunocompetent male with recurrent leg cellulitis. The cellulitis eventually developed into a non-healing ulcer and a palpable nodule consistent with nodular Kaposi's sarcoma.


Assuntos
Sarcoma de Kaposi , Idoso , Humanos , Imunocompetência , Masculino , Sarcoma de Kaposi/patologia , Sarcoma de Kaposi/terapia
20.
Trop Anim Health Prod ; 45(7): 1489-94, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23471709

RESUMO

The objective of this study was to determine the magnitude of genotype by climate interaction (GCI) in the national genetic evaluation for weaning (WW) and yearling (YW) weights of Mexican Braunvieh cattle. The numbers of performance records and animals in the pedigree were 12,364 and 25,173 for WW, and 7,991 and 18,072 for YW, respectively. Performance records were clustered based on climatological variables into: dry tropic (DT), wet tropic (WT), and temperate (TE) climates. Animal models were used to estimate genetic parameters and predict breeding values in each of the climates. Bivariate analyses were carried out for pairwise combinations of climates on each trait, considering the same trait in different climates as a different trait. Criteria to evaluate GCI were genetic correlations (r g), correlations between predicted breeding values (r BV), and frequencies of coincidence (FC) in the ranking of the top 25 sires. Results of comparisons between pairs of climates were variable, depending on specific cases. For WW, the r g, r BV, and FC ranged from -0.36 to 0.84, -0.60 to 0.97, and 0.16 to 0.92, respectively; whereas for YW, they fluctuated between 0.23 and 0.99, 0.33 and 1.00, and 0.60 and 1.00, respectively. For both traits, the results suggest absence of GCI between DT and TE; however, GCI was detected in the other pairs of climates, where WT was involved. To maximize genetic progress, the joint genetic evaluation should be performed only for animals with performance data in DT and TE, whereas a separated evaluation is suggested for animals with performance records generated under WT conditions.


Assuntos
Bovinos/crescimento & desenvolvimento , Bovinos/genética , Interação Gene-Ambiente , Aumento de Peso , Animais , Peso Corporal , Clima , Feminino , Genótipo , Masculino , México , Modelos Biológicos , Análise Multivariada , Estações do Ano , Clima Tropical , Desmame
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