70 research outputs found
Data on individual PCR efficiency values as quality control for circulating miRNAs
AbstractThis data article contains data related to the research article entitled “Variability in microRNA recovery from plasma: Comparison of five commercial kits, doi:10.1016/j.ab.2015.07.018” Brunet-Vega (2015) [1]. PCR efficiency, along with RNA and cDNA quality, are the most important factors affecting the quality of qPCR results. Constant amplification efficiency in all compared samples is indispensable when relative quantification is used to measure changes in gene expression. An easy way to measure PCR efficiency, without the need of a standard curve, is LinRegPCR software. Individual PCR efficiency can be determined as a part of qPCR quality control. This is especially important when the initial RNA quantity is so low that cannot be accurately quantified, such as in circulating RNA extractions. This data article reports the Cqs and PCR efficiencies of 5 miRNAs quantified in RNA isolated from 4 patients with colorectal cancer (CRC) and 4 healthy donors using five commercially available kits
Whole-Genome Sequencing and Comparative Genomics of Three Helicobacter pylori Strains Isolated from the Stomach of a Patient with Adenocarcinoma
Helicobacter pylori is a common pathogen associated with several severe digestive diseases. Although multiple virulence factors have been described, it is still unclear the role of virulence factors on H. pylori pathogenesis and disease progression. Whole genome sequencing could help to find genetic markers of virulence strains. In this work, we analyzed three complete genomes from isolates obtained at the same point in time from a stomach of a patient with adenocarcinoma, using multiple available bioinformatics tools. The genome analysis of the strains B508A-S1, B508A-T2A and B508A-T4 revealed that they were cagA, babA and sabB/hopO negative. The differences among the three genomes were mainly related to outer membrane proteins, methylases, restriction modification systems and flagellar biosynthesis proteins. The strain B508A-T2A was the only one presenting the genotype vacA s1, and had the most distinct genome as it exhibited fewer shared genes, higher number of unique genes, and more polymorphisms were found in this genome. With all the accumulated information, no significant differences were found among the isolates regarding virulence and origin of the isolates. Nevertheless, some B508A-T2A genome characteristics could be linked to the pathogenicity of H. pylori. Keywords: Helicobacter pylori; genomic comparison; virulence factors; gastric adenocarcinom
Usefulness of Housekeeping Genes for the Diagnosis of Helicobacter pylori Infection, Strain Discrimination and Detection of Multiple Infection
Background: Helicobacter pylori infects human stomachs of over half the world's population, evades the immune response and establishes a chronic infection. Although most people remains asymptomatic, duodenal and gastric ulcers, MALT lymphoma and progression to gastric cancer could be developed. Several virulence factors such as flagella, lipopolysaccharide, adhesins and especially the vacuolating cytotoxin VacA and the oncoprotein CagA have been described for H. pylori. Despite the extensive published data on H. pylori, more research is needed to determine new virulence markers, the exact mode of transmission or the role of multiple infection. Materials and Methods: Amplification and sequencing of six housekeeping genes (amiA, cgt, cpn60, cpn70, dnaJ, and luxS) related to H. pylori pathogenesis have been performed in order to evaluate their usefulness for the specific detection of H. pylori, the genetic discrimination at strain level and the detection of multiple infection. A total of 52 H. pylori clones, isolated from 14 gastric biopsies from 11 patients, were analyzed for this purpose. Results: All genes were specifically amplified for H. pylori and all clones isolated from different patients were discriminated, with gene distances ranged from 0.9 to 7.8%. Although most clones isolated from the same patient showed identical gene sequences, an event of multiple infection was detected in all the genes and microevolution events were showed for amiA and cpn60 genes. Conclusions: These results suggested that housekeeping genes could be useful for H. pylori detection and to elucidate the mode of transmission and the relevance of the multiple infection
Droplet Digital PCR Detects Low-Density Infection in a Significant Proportion of Helicobacter Pylori -Negative Gastric Biopsies of Dyspeptic Patients
Dyspeptic patients (n = 236) were tested for H. pylori by histology, urea breath test, and rapid urease test. Patients were classified as having 3 positive (n = 25, control group), 2 positive (n = 12), one positive (n = 41), or zero positive (n = 158) diagnostic tests. DNA was extracted from gastric biopsies. Triplicate ddPCR testing for each of the 16S rDNA, ureA, and vacA(s) genes was performed using a QX200 ddPCR system (Bio-Rad). A gene was considered positive when detected by at least 2 of 3 repeated ddPCRs. H. pylori positivity was defined as having 2 or more positive genes. All the biopsies of the control patients were positive for all 3 16S rDNA, ureA, and vacA(s) genes. H. pylori infection was detected in 57 (36%), 22 (54%), and 9 (75%) patients with zero, 1, and 2 positive diagnostic tests, respectively. The density of infection was 5, 121, 599, and 3,133 copies of H. pylori genome equivalents for patients with zero, 1, and 2 of 3 positive test results and for the control group, respectively. ddPCR detected low-density "occult" H. pylori infection in a significant proportion (36%) of patients diagnosed as negative by conventional methods. The number of conventional positive tests was related to the density of infection
Detection of Helicobacter pylori Microevolution and Multiple Infection from Gastric Biopsies by Housekeeping Gene Amplicon Sequencing
Despite the great efforts devoted to research on Helicobacter pylori, the prevalence of single-strain infection or H. pylori mixed infection and its implications in the mode of transmission of this bacterium are still controversial. In this study, we explored the usefulness of housekeeping gene amplicon sequencing in the detection of H. pylori microevolution and multiple infections. DNA was extracted from five gastric biopsies from four patients infected with distinct histopathological diagnoses. PCR amplification of six H. pylori-specific housekeeping genes was then assessed on each sample. Optimal results were obtained for the cgt and luxS genes, which were selected for amplicon sequencing. A total of 11,833 cgt and 403 luxS amplicon sequences were obtained, 2042 and 112 of which were unique sequences, respectively. All cgt and luxS sequences were clustered at 97% to 9 and 13 operational taxonomic units (OTUs), respectively. For each sample from a different patient, a single OTU comprised the majority of sequences in both genes, but more than one OTU was detected in all samples. These results suggest that multiple infections with a predominant strain together with other minority strains are the main way by which H. pylori colonizes the human stomach
Motivación laboral y rendimiento en el trabajo de los colaboradores de las municipalidades distritales de Áncash
La motivación en el trabajo es la clave del éxito institucional y, dado que tanto la motivación como el rendimiento laboral son de gran interés en las instituciones públicas, se deduce que la primera es crucial para la segunda. El objetivo del estudio fue determinar si la motivación intrínseca tenía alguna relación con el rendimiento en el trabajo de los colaboradores en los municipios rurales de Ancash. El estudio es descriptivo-correlacional no experimental, con un tamaño de muestra estadísticamente determinado de 132 trabajadores de 6 distritos rurales (Olleros, Pira, Ataquero, Amashca, Yanama y Huata) que respondieron a un cuestionario compuesto por 77 preguntas (59 sobre motivación laboral y 18 sobre rendimiento en el trabajo). Se evidencia que las municipalidades distritales de Olleros y Yanama se encuentran mejor posicionadas en ambas variables y las municipalidades Pira y Ataquero tienen la posición más baja. Se concluye que los trabajadores de las municipalidades distritales rurales de Ancash tienen una asociación moderadamente positiva entre la motivación laboral y el rendimiento en el trabajo
Follow-Up Study Confirms the Presence of Gastric Cancer DNA Methylation Hallmarks in High-Risk Precursor Lesions
Intestinal metaplasia confers an increased risk of progression to gastric cancer. However, some intestinal metaplasia patients do not develop cancer. The development of robust molecular biomarkers to stratify patients with advanced gastric precursor lesions at risk of cancer progression will contribute to guiding programs for prevention. Starting from a genome-wide methylation study, we have simplified the detection method regarding candidate-methylation tests to improve their applicability in the clinical environment. We identified CpG methylation at the ZNF793 and RPRM promoters as a common event in intestinal metaplasia and intestinal forms of gastric cancer. Furthermore, we also showed that Helicobacter pylori infection influences DNA methylation in early precursor lesions but not in intestinal metaplasia, suggesting that therapeutic strategies to prevent epigenome reprogramming toward a cancer signature need to be adopted early in the precursor cascade. To adopt prevention strategies in gastric cancer, it is imperative to develop robust biomarkers with acceptable costs and feasibility in clinical practice to stratified populations according to risk scores. With this aim, we applied an unbiased genome-wide CpG methylation approach to a discovery cohort composed of gastric cancer (n = 24), and non-malignant precursor lesions (n = 64). Then, candidate-methylation approaches were performed in a validation cohort of precursor lesions obtained from an observational longitudinal study (n = 264), with a 12-year follow-up to identify repression or progression cases. H. pylori stratification and histology were considered to determine their influence on the methylation dynamics. As a result, we ascertained that intestinal metaplasia partially recapitulates patterns of aberrant methylation of intestinal type of gastric cancer, independently of the H. pylori status. Two epigenetically regulated genes in cancer, RPRM and ZNF793, consistently showed increased methylation in intestinal metaplasia with respect to earlier precursor lesions. In summary, our result supports the need to investigate the practical utilities of the quantification of DNA methylation in candidate genes as a marker for disease progression. In addition, the H. pylori-dependent methylation in intestinal metaplasia suggests that pharmacological treatments aimed at H. pylori eradication in the late stages of precursor lesions do not prevent epigenome reprogramming toward a cancer signature
Home parenteral nutrition registry in Spain for the year 2010: NADYA-SENPE group
Objetivos: Comunicar los datos del Registro del Grupo
NADYA SENPE de Nutrición Parenteral Domiciliaria
NPD en España del año 2010.
Material y métodos: Estudio descriptivo de la base de
datos del Registro de ámbito nacional de NPD del grupo
NADYA-SENPE (1 de enero de 2010 al 31 de diciembre de
2010). Para el cálculo de prevalencias se utilizó los últimos
datos publicados por el Instituto Nacional de Estadística.
Resultados: Se registraron 148 pacientes procedentes de
23 hospitales, 86 mujeres (58,11%) y 9 niños (6,08%). La
edad media de los 139 pacientes adultos fue de 53,06 ±
15,41 años. La duración media de la NPD fue de 316,97
días/paciente. El diagnóstico más frecuente en los niños
(menores de 14 años) fue intestino corto traumático con 5
casos (55,55%) y en los adultos la neoplasia en tratamiento
paliativo 29 (19,59%). El motivo de la indicación de la NPD
fue el síndrome de intestino corto en 74 ocasiones (47%).
La vía de acceso más frecuentemente registrada fue el catéter
tunelizado en 36 (22,78%) casos seguido del reservorio
en 13 (8,23%) y otras vías en 3 ocasiones (1,90%). Se registraron
23 infecciones relacionadas con el catéter (82,14%),
lo que representa 0,49/1000 días de NP y todas ellas ocurrieron
en los adultos. A lo largo del año finalizaron 24 episodios
de NPD, la causa más frecuente fue el paso a la vía
oral en 12 episodios (50%). Se registró que los pacientes
tenían una actividad normal en 70 episodios de NPD
(44,30%) con una total autonomía en 88 de episodios
(55,69%). Se identificaron 39 (24,68%) posibles candidatos
para trasplante intestinal.
Conclusiones: El número de pacientes registrados es
discretamente inferior al del año anterior, aunque el
número de hospitales participantes es el mismo. La complicación
más frecuente sigue siendo la infección relacionada
con el catéter aunque ha disminuido su incidencia
respecto a años anteriores, presentándose la tasa más
baja desde la creación del registro.
Las diferencias en la participación en el registro observadas
por Comunidades Autónomas lleva a plantear el
desarrollo de estrategias de implementación del registro.
Se observa un aumento progresivo de la duración de los
días de NPD a lo largo de los años que hace pensar en la
cronicidad de algunos pacientes, pero nos obliga a estudiar
la existencia de un posible factor de confusión, en el
caso de que existiera un olvido de cierre de algún episodio
por lo que se hace necesario actualizar el registro con sistemas
de alertas periódicas que faciliten la revisión de los
pacientes incluidos y optimice la validez del registroObjectives: To report the Group Registry NADYASENPE
data about home parenteral nutrition (HPN) in
Spain in 2010.
Material and methods: A descriptive study of the database
of the national registry of HPN of NADYA-SENPE
(December 10, 2009 to December 10, 2010). For the calculation
of prevalence the latest data published by the Institute
National Statistics Office (01/01/2009) was used.
Results: There were registered 148 patients from 23
hospitals, 86 women (58.11%) and 9 children (6.08%).
The average age of the 139 patients older than 14 years
was 53.06 ± 15.41 years. The average duration of HPN
was 316.97 days/patient. The most common diagnosis in
those younger than 14 years was short bowel traumatic
with 5 cases (55.55%) and in those older than 14 years,
palliative care cancer with 29 cases (19.59%). The reason
for the indication for HPN was short bowel syndrome in
74 cases (47%). The access via most frequently recorded
was tunneled catheter in 36 cases (22.78%) followed by
implanted port-catheters in 13 cases (8.23%) and other
pathways in 3 cases (1.90%). There were 23 catheterrelated
infections (82.14%) which represented 0.49 /1,000
days of PN, all of which occurred in cases older than 14
years. During the year 24 episodes of HPN ended, the
most frequent cause was the transition to oral nutrition in
12 episodes (50%). It was reported that patients had a
normal activity in 70 episodes of HPN (44.30%) with complete
autonomy in 88 episodes (55.69%). Some patients 39
(24.68%) were potential candidates for intestinal transplantation.
Conclusions: The number of registered patients is
slightly lower than the previous year, although the number
of participating hospitals is the same. The most frequent
complication remains catheter-related infection
but its incidence has decreased from previous years, presenting
the lowest rate since the creation of the record.
Differences in participation in the registry observed in
the Autonomous Communities causes the development of
implementation strategies. There is a gradual increase in
day length of HPN over the years, which suggests the
chronic treatments of some patients and obliges to study
the existence of a possible confounding factor, in case
there is an oversight of closing an episode. Therefore, it is
necessary to update the registry with warning systems
that facilitate periodic review of the patients and optimize
the validity of registratio
Decapping Protein Edc4 Regulates Dna Repair And Phenocopies Brca1
BRCA1 is a tumor suppressor that regulates DNA repair by homologous recombination. Germline mutations in BRCA1 are associated with increased risk of breast and ovarian cancer and BRCA1 deficient tumors are exquisitely sensitive to poly (ADP-ribose) polymerase (PARP) inhibitors. Therefore, uncovering additional components of this DNA repair pathway is of extreme importance for further understanding cancer development and therapeutic vulnerabilities. Here, we identify EDC4, a known component of processing-bodies and regulator of mRNA decapping, as a member of the BRCA1-BRIP1-TOPBP1 complex. EDC4 plays a key role in homologous recombination by stimulating end resection at double-strand breaks. EDC4 deficiency leads to genome instability and hypersensitivity to DNA interstrand cross-linking drugs and PARP inhibitors. Lack-of-function mutations in EDC4 were detected in BRCA1/2-mutation-negative breast cancer cases, suggesting a role in breast cancer susceptibility. Collectively, this study recognizes EDC4 with a dual role in decapping and DNA repair whose inactivation phenocopies BRCA1 deficiency
Knowledge to Serve the City: Insights from an Emerging Knowledge-Action Network to Address Vulnerability and Sustainability in San Juan, Puerto Rico
This paper presents initial efforts to establish the San Juan Urban Long-Term Research Area Exploratory (ULTRA-Ex), a long-term program aimed at developing transdisciplinary social-ecological system (SES) research to address vulnerability and sustainability for the municipality of San Juan. Transdisciplinary approaches involve the collaborations between researchers, stakeholders, and citizens to produce socially-relevant knowledge and support decision-making. We characterize the transdisciplinary arrangement emerging in San Juan ULTRA-Ex as a knowledge-action network composed of multiple formal and informal actors (e.g., scientists, policymakers, civic organizations and other stakeholders) where knowledge, ideas, and strategies for sustainability are being produced, evaluated, and validated. We describe in this paper the on-the-ground social practices and dynamics that emerged from developing a knowledge-action network in our local context. Specifically, we present six social practices that were crucial to the development of our knowledge-action network: 1) understanding local framings; 2) analyzing existing knowledge-action systems in the city; 3) framing the social-ecological research agenda; 4) collaborative knowledge production and integration; 5) boundary objects and practices; and 6) synthesis, application, and adaptation. We discuss key challenges and ways to move forward in building knowledge-action networks for sustainability. Our hope is that the insights learned from this process will stimulate broader discussions on how to develop knowledge for urban sustainability, especially in tropical cities where these issues are under-explored
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