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1.
Crit Care ; 27(1): 72, 2023 02 23.
Artículo en Inglés | MEDLINE | ID: mdl-36823625

RESUMEN

BACKGROUND: Severe community-acquired pneumococcal meningitis is a medical emergency. The aim of the present investigation was to evaluate the epidemiology, management and outcomes of this condition. METHODS: This was a retrospective, observational and multicenter cohort study. Sixteen Spanish intensive care units (ICUs) were included. Demographic, clinical and microbiological variables from patients with Streptococcus pneumoniae meningitis admitted to ICU were evaluated. Clinical response was evaluated at 72 h after antibiotic treatment initiation, and meningitis complications, length of stay and 30-day mortality were also recorded. RESULTS: In total, 255 patients were included. Cerebrospinal fluid (CSF) culture was positive in 89.7%; 25.7% were non-susceptible to penicillin, and 5.2% were non-susceptible to ceftriaxone or cefotaxime. The most frequent empiric antibiotic regimen was third-generation cephalosporin (47.5%) plus vancomycin (27.8%) or linezolid (12.9%). A steroid treatment regimen was administered to 88.6% of the patients. Clinical response was achieved in 65.8% of patients after 72 h of antibiotic treatment. Multivariate analysis identified two factors associated with early treatment failure: invasive mechanical ventilation (OR 10.74; 95% CI 3.04-37.95, p < 0.001) and septic shock (OR 1.18; 95% CI 1.03-1.36, p = 0.017). The 30-day mortality rate was 13.7%. Only three factors were independently associated with 30-day mortality: delay in start of antibiotic treatment (OR 18.69; 95% CI 2.13-163.97, p = 0.008), Sepsis-related Organ Failure Assessment (SOFA) score (OR 1.36; 95% CI 1.12-1.66, p = 0.002) and early treatment failure (OR 21.75 (3.40-139.18), p = 0.001). Neurological complications appeared in 124 patients (48.63%). CONCLUSIONS: Mortality rate in critically ill patients with pneumococcal meningitis is lower than previously reported. Delay in antibiotic treatment following admission is the only amendable factor associated with mortality.


Asunto(s)
Meningitis Neumocócica , Humanos , Streptococcus pneumoniae , Pronóstico , Estudios de Cohortes , Antibacterianos/uso terapéutico , Estudios Retrospectivos , Unidades de Cuidados Intensivos
2.
Sensors (Basel) ; 22(23)2022 Dec 02.
Artículo en Inglés | MEDLINE | ID: mdl-36502129

RESUMEN

The synovial fluid (SF) analysis involves a series of chemical and physical studies that allow opportune diagnosing of septic, inflammatory, non-inflammatory, and other pathologies in joints. Among the variety of analyses to be performed on the synovial fluid, the study of viscosity can help distinguish between these conditions, since this property is affected in pathological cases. The problem with viscosity measurement is that it usually requires a large sample volume, or the necessary instrumentation is bulky and expensive. This study compares the viscosity of normal synovial fluid samples with samples with infectious and inflammatory pathologies and classifies them using an ANN (Artificial Neural Network). For this purpose, a low-cost, portable QCR-based sensor (10 MHz) was used to measure the viscous responses of the samples by obtaining three parameters: Δf, ΔΓ (parameters associated with the viscoelastic properties of the fluid), and viscosity calculation. These values were used to train the algorithm. Different versions of the ANN were compared, along with other models, such as SVM and random forest. Thirty-three samples of SF were analyzed. Our study suggests that the viscosity characterized by our sensor can help distinguish infectious synovial fluid, and that implementation of ANN improves the accuracy of synovial fluid classification.


Asunto(s)
Líquido Sinovial , Líquido Sinovial/química , Viscosidad
3.
Scand J Clin Lab Invest ; 81(3): 187-193, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33591234

RESUMEN

Identification of predictors for severe disease progression is key for risk stratification in COVID-19 patients. We aimed to describe the main characteristics and identify the early predictors for severe outcomes among hospitalized patients with COVID-19 in Spain. This was an observational, retrospective cohort study (BIOCOVID-Spain study) including COVID-19 patients admitted to 32 Spanish hospitals. Demographics, comorbidities and laboratory tests were collected. Outcome was in-hospital mortality. For analysis, laboratory tests values were previously adjusted to assure the comparability of results among participants. Cox regression was performed to identify predictors. Study population included 2873 hospitalized COVID-19 patients. Nine variables were independent predictors for in-hospital mortality, including creatinine (Hazard ratio [HR]:1.327; 95% Confidence Interval [CI]: 1.040-1.695, p = .023), troponin (HR: 2.150; 95% CI: 1.155-4.001; p = .016), platelet count (HR: 0.994; 95% CI: 0.989-0.998; p = .004) and C-reactive protein (HR: 1.037; 95% CI: 1.006-1.068; p = .019). This is the first multicenter study in which an effort was carried out to adjust the results of laboratory tests measured with different methodologies to guarantee their comparability. We reported a comprehensive information about characteristics in a large cohort of hospitalized COVID-19 patients, focusing on the analytical features. Our findings may help to identify patients early at a higher risk for an adverse outcome.


Asunto(s)
COVID-19/diagnóstico , Servicio de Urgencia en Hospital , SARS-CoV-2 , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , COVID-19/mortalidad , Femenino , Mortalidad Hospitalaria , Hospitalización , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , España/epidemiología , Adulto Joven
4.
Proc Natl Acad Sci U S A ; 114(3): 443-450, 2017 01 17.
Artículo en Inglés | MEDLINE | ID: mdl-28049850

RESUMEN

Genetic recombination provides an important mechanism for the repair of DNA double-strand breaks. Homologous pairing and strand exchange lead to the formation of DNA intermediates, in which sister chromatids or homologous chromosomes are covalently linked by four-way Holliday junctions (HJs). Depending on the type of recombination reaction that takes place, intermediates may have single or double HJs, and their resolution is essential for proper chromosome segregation. In mitotic cells, double HJs are primarily dissolved by the BLM helicase-TopoisomeraseIIIα-RMI1-RMI2 (BTR) complex, whereas single HJs (and double HJs that have escaped the attention of BTR) are resolved by structure-selective endonucleases known as HJ resolvases. These enzymes are ubiquitous in nature, because they are present in bacteriophage, bacteria, archaea, and simple and complex eukaryotes. The human HJ resolvase GEN1 is a member of the XPG/Rad2 family of 5'-flap endonucleases. Biochemical studies of GEN1 revealed that it cleaves synthetic DNA substrates containing a single HJ by a mechanism similar to that shown by the prototypic HJ resolvase, Escherichia coli RuvC protein, but it is unclear whether these substrates fully recapitulate the properties of recombination intermediates that arise within a physiological context. Here, we show that GEN1 efficiently cleaves both single and double HJs contained within large recombination intermediates. Moreover, we find that GEN1 exhibits a weak sequence preference for incision between two G residues that reside in a T-rich region of DNA. These results contrast with those obtained with RuvC, which exhibits a strict requirement for the consensus sequence 5'-A/TTTG/C-3'.


Asunto(s)
ADN Cruciforme/genética , ADN Cruciforme/metabolismo , Resolvasas de Unión Holliday/metabolismo , Secuencia de Bases , Reparación del ADN , ADN Cruciforme/química , Endodesoxirribonucleasas/química , Endodesoxirribonucleasas/metabolismo , Proteínas de Escherichia coli/química , Proteínas de Escherichia coli/metabolismo , Resolvasas de Unión Holliday/química , Recombinación Homóloga , Humanos , Modelos Moleculares , Conformación de Ácido Nucleico , Conformación Proteica , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Especificidad por Sustrato
5.
Sensors (Basel) ; 20(24)2020 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-33322660

RESUMEN

Efficiency in power lines operation is becoming more crucial as the electrification increases and more renewable energies are connected into the grid. New methods and sensors are being added to create smart grids to face these challenges and conductor temperature sensors are one of them. Contact temperature sensors have several problems regarding safety and electronic damage due to the electromagnetic fields induced on the conductors. The goal of this paper is to describe an infrared temperature measurement sensor and to compare contact and non-contact temperature measurements to estimate the temperature of power lines. Measurements were done for almost a year, storing around 150,000 measures of contact and infrared thermometers for many different weather and load conditions. The results conclude that the infrared system can be successfully used to control the temperature of the overhead conductor within a range of less than 4 ∘C difference with respect to contact temperature methods for the 88% of the samples and less than 6 ∘C for the 99%.

6.
Artículo en Inglés | MEDLINE | ID: mdl-27895014

RESUMEN

Ceftazidime-avibactam (CAZ-AVI) is a recently approved ß-lactam-ß-lactamase inhibitor combination with the potential to treat serious infections caused by carbapenem-resistant organisms. Few patients with such infections were included in the CAZ-AVI clinical trials, and clinical experience is lacking. We present a case series of patients with infections caused by carbapenem-resistant Enterobacteriaceae (CRE) or Pseudomonas aeruginosa (CRPa) who were treated with CAZ-AVI salvage therapy on a compassionate-use basis. Physicians who had prescribed CAZ-AVI completed a case report form. We used descriptive statistics to summarize patient characteristics and treatment outcomes. We used the Wilcoxon rank sum test and Fisher's exact test to compare patients by treatment outcome. The sample included 36 patients infected with CRE and two with CRPa. The most common infections were intra-abdominal. Physicians categorized 60.5% of patients as having life-threatening infections. All but two patients received other antibiotics before CAZ-AVI, for a median of 13 days. The median duration of CAZ-AVI treatment was 16 days. Twenty-five patients (65.8%) concurrently received other antibiotics to which their pathogen was nonresistant in vitro Twenty-eight patients (73.7%, 95% confidence interval [CI], 56.9 to 86.6%) experienced clinical and/or microbiological cure. Five patients (20.8%) with documented microbiological cure died, whereas 10 patients (71.4%) with no documented microbiological cure died (P = 0.01). In three-quarters of cases, CAZ-AVI (alone or combined with other antibiotics) cured infections caused by carbapenem-resistant organisms, 95% of which had failed previous therapy. Microbiological cure was associated with improved survival. CAZ-AVI shows promising clinical results for infections for which treatment options are limited.


Asunto(s)
Antibacterianos/uso terapéutico , Compuestos de Azabiciclo/uso terapéutico , Carbapenémicos/uso terapéutico , Ceftazidima/uso terapéutico , Anciano , Antibacterianos/farmacología , Compuestos de Azabiciclo/farmacología , Carbapenémicos/farmacología , Ceftazidima/farmacología , Combinación de Medicamentos , Enterobacteriaceae/efectos de los fármacos , Enterobacteriaceae/patogenicidad , Femenino , Humanos , Klebsiella oxytoca/efectos de los fármacos , Klebsiella oxytoca/patogenicidad , Klebsiella pneumoniae/efectos de los fármacos , Klebsiella pneumoniae/patogenicidad , Masculino , Pruebas de Sensibilidad Microbiana , Persona de Mediana Edad , Pseudomonas aeruginosa/efectos de los fármacos , Pseudomonas aeruginosa/patogenicidad , Terapia Recuperativa
7.
Echocardiography ; 34(6): 869-875, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28378340

RESUMEN

INTRODUCTION: Peak exercise echocardiogram (EEcho) has shown reasonable sensitivity and specificity in detecting significant coronary artery disease (CAD). The objective was to evaluate the prognostic value of EEcho in patients hospitalized for acute chest pain (CP) and its additional prognostic information regarding exercise electrocardiogram test (EECG). METHODS: Prospective observational study performed between May 2011 and September 2013, including 250 patients consecutively admitted for acute CP with normal cardiac biomarkers and nondiagnostic electrocardiogram. All patients were prospectively followed for 1 year, and major adverse cardiovascular events (MACE) were recorded: cardiac death, nonfatal myocardial infarction (MI), or angina with coronary revascularization. RESULTS: EEcho was positive in 16%. Patients with positive EEcho had a higher incidence of hypertension and higher TIMI risk score, showing significant CAD in 66%. We observed contradictory results (EECG-EEcho) in 20%. Patients with positive EEcho and negative EECG had significant CAD in the 66%, and patients undergoing coronary angiography with negative EEcho and positive EECG did not show significant coronary artery disease. Only positive EEcho (P<.001, HR 0.169; 95% CI, 0.088-0.250) and atrial fibrillation (P<.025, HR 0.125; 95% CI, 0.016-0.233) were independently associated with MACE during follow-up. In patients with negative EEcho, the presence of MACE was 2%. CONCLUSIONS: EEcho in patients hospitalized for acute chest pain presents good ability to diagnose acute coronary syndrome, while providing additional information when combined with an EECG in up to 20% of cases. Moreover, a negative EEcho in this cohort seems to provide prognostic information beyond the acute event to predict long-term MACE.


Asunto(s)
Dolor en el Pecho/etiología , Ecocardiografía/métodos , Prueba de Esfuerzo/estadística & datos numéricos , Cardiopatías/complicaciones , Cardiopatías/diagnóstico por imagen , Hospitalización/estadística & datos numéricos , Enfermedad Aguda , Anciano , Dolor en el Pecho/fisiopatología , Electrocardiografía/métodos , Femenino , Cardiopatías/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Pronóstico , Estudios Prospectivos , Medición de Riesgo , Factores de Riesgo , Sensibilidad y Especificidad
8.
Nucleic Acids Res ; 42(12): 7923-34, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24878922

RESUMEN

Human Polµ is a DNA polymerase belonging to the X family that has been implicated in the non-homologous end-joining (NHEJ) pathway during repair of double-strand breaks in DNA. Loop1 is a flexible piece of Polµ which has a critical role during terminal transferase and end-joining activities: it acts as a pseudo-template when the template strand is discontinuous or unavailable, whilst diffusing away if present to avoid steric clashes. Mutational analysis and inspection of the 3D structures available allowed us to identify a network of residues in charge of sensing the presence or absence of discontinuities in the template strand, which will in turn determine the final position adopted by Loop1. This network is formed by the previously uncharacterized thumb mini-loop (NSH motif) and the positively charged helix N, which contribute to the correct positioning of Loop1 and to juxtapose the discontinuous template strand during NHEJ of incompatible ends. Accordingly, single mutation of specific conserved residues in these motifs, whilst irrelevant in most of the cases for gap filling, largely affected terminal transferase and end-joining activities. Other point mutations in the 'hinges' of Loop1, such as residues Phe385 or Phe389, corroborated the flexibility requirements of this motif.


Asunto(s)
Reparación del ADN por Unión de Extremidades , ADN Polimerasa Dirigida por ADN/química , Arginina/química , ADN Nucleotidilexotransferasa/química , ADN Nucleotidilexotransferasa/genética , ADN Nucleotidilexotransferasa/metabolismo , ADN Polimerasa Dirigida por ADN/genética , ADN Polimerasa Dirigida por ADN/metabolismo , Humanos , Modelos Moleculares , Mutación
9.
Anal Biochem ; 480: 42-8, 2015 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-25892220

RESUMEN

The study of monocyte activation and differentiation has great applications in sepsis, chronic inflammatory diseases, and cancer studies. However, despite the existence of well-established protocols for monocyte purification from human blood, the isolation of murine monocytes that can be subsequently activated has not yet been fully optimized. Here we evaluate a recently developed commercial procedure for obtaining monocytes from the bone marrow based on immunomagnetic depletion of non-monocytic cells. Moreover, we compare the advantages and disadvantages of this approach relative to other existing procedures. We found that monocytes isolates generated using this technique had equal purity to those attained via depletion from peripheral blood; however, higher yields were achieved. Furthermore, isolates from this technique have lower levels of macrophage contamination than those reported in samples generated by culturing bone marrow extracts with macrophage colony-stimulating factor (M-CSF). In addition, we demonstrate that the purified monocytes are sensitive to lipopolysaccharide (LPS)-mediated activation and, therefore, are useful for studies aimed at elucidating the molecular mechanisms involved in monocyte activation and differentiation.


Asunto(s)
Células de la Médula Ósea , Separación Celular , Monocitos/citología , Animales , Células de la Médula Ósea/efectos de los fármacos , Lipopolisacáridos/farmacología , Ratones , Ratones Endogámicos C57BL , Monocitos/efectos de los fármacos
10.
Nucleic Acids Res ; 41(1): 253-63, 2013 Jan 07.
Artículo en Inglés | MEDLINE | ID: mdl-23143108

RESUMEN

Polµ is the only DNA polymerase equipped with template-directed and terminal transferase activities. Polµ is also able to accept distortions in both primer and template strands, resulting in misinsertions and extension of realigned mismatched primer terminus. In this study, we propose a model for human Polµ-mediated dinucleotide expansion as a function of the sequence context. In this model, Polµ requires an initial dislocation, that must be subsequently stabilized, to generate large sequence expansions at different 5'-P-containing DNA substrates, including those that mimic non-homologous end-joining (NHEJ) intermediates. Our mechanistic studies point at human Polµ residues His(329) and Arg(387) as responsible for regulating nucleotide expansions occurring during DNA repair transactions, either promoting or blocking, respectively, iterative polymerization. This is reminiscent of the role of both residues in the mechanism of terminal transferase activity. The iterative synthesis performed by Polµ at various contexts may lead to frameshift mutations producing DNA damage and instability, which may end in different human disorders, including cancer or congenital abnormalities.


Asunto(s)
Reparación del ADN por Unión de Extremidades , Expansión de las Repeticiones de ADN , ADN Polimerasa Dirigida por ADN/metabolismo , Arginina/química , ADN Polimerasa beta/metabolismo , ADN Polimerasa Dirigida por ADN/química , Histidina/química , Humanos , Moldes Genéticos , Repeticiones de Trinucleótidos
11.
Nucleic Acids Res ; 41(4): 2428-36, 2013 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-23275568

RESUMEN

Human DNA polymerase mu (Polµ), a family X member involved in DNA repair, has both template-directed and terminal transferase (template-independent) activities. In addition to their ability to incorporate untemplated nucleotides, another similarity between Polµ and terminal deoxynucleotidyl transferase (TdT) is their promiscuity in using ribonucleotides (NTPs), whose physiological significance is presently unknown. As shown here, Polµ can use NTPs instead of deoxynucleotides (dNTPs) during non-homologous end joining (NHEJ) of non-complementary ends, a Polµ-specific task. Moreover, a physiological concentration of Mn(2+) ions did benefit Polµ-mediated NHEJ by improving the efficiency and accuracy of nucleotide insertion. Analysis of different mutations in the 'steric gate' of the active site indicated that Polµ is taking advantage of an open active site, valid for selecting alternative activating metal ions and nucleotides as substrates. This versatility would allow ad hoc selection of the most appropriate nucleotide/metal ion combination for individual NHEJ events to gain efficiency without a cost in terms of fidelity, thus widening the spectrum of available solutions to position a discontinuous template strand in proper register for connection.


Asunto(s)
Reparación del ADN por Unión de Extremidades , ADN Polimerasa Dirigida por ADN/metabolismo , Manganeso/farmacología , Ribonucleótidos/metabolismo , Dominio Catalítico , Cationes , ADN Polimerasa beta/metabolismo , ADN Polimerasa Dirigida por ADN/química , Células HeLa , Humanos , Manganeso/química , Schizosaccharomyces/metabolismo , Proteínas de Schizosaccharomyces pombe/metabolismo
12.
Nucleic Acids Res ; 41(19): 9105-16, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23935073

RESUMEN

Human DNA polymerases mu (Polµ) and lambda (Polλ) are X family members involved in the repair of double-strand breaks in DNA during non-homologous end joining. Crucial abilities of these enzymes include bridging of the two 3' single-stranded overhangs and trans-polymerization using one 3' end as primer and the other as template, to minimize sequence loss. In this context, we have studied the importance of a previously uncharacterised sequence ('brooch'), located at the N-terminal boundary of the Polß-like polymerase core, and formed by Tyr(141), Ala(142), Cys(143), Gln(144) and Arg(145) in Polµ, and by Trp(239), Val(240), Cys(241), Ala(242) and Gln(243) in Polλ. The brooch is potentially implicated in the maintenance of a closed conformation throughout the catalytic cycle, and our studies indicate that it could be a target of Cdk phosphorylation in Polµ. The brooch is irrelevant for 1 nt gap filling, but of specific importance during end joining: single mutations in the conserved residues reduced the formation of two ended synapses and strongly diminished the ability of Polµ and polymerase lambda to perform non-homologous end joining reactions in vitro.


Asunto(s)
ADN Polimerasa beta/química , ADN Polimerasa Dirigida por ADN/química , ADN/metabolismo , Secuencia de Aminoácidos , Quinasas Ciclina-Dependientes/metabolismo , Reparación del ADN por Unión de Extremidades , ADN Polimerasa beta/metabolismo , ADN Polimerasa Dirigida por ADN/genética , ADN Polimerasa Dirigida por ADN/metabolismo , Humanos , Datos de Secuencia Molecular , Mutación , Fosforilación , Unión Proteica , Conformación Proteica , Estructura Terciaria de Proteína
13.
Nucleic Acids Res ; 40(22): 11389-403, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23034807

RESUMEN

Non-homologous end-joining (NHEJ), the preferred pathway to repair double-strand breaks (DSBs) in higher eukaryotes, relies on a collection of molecular tools to process the broken ends, including specific DNA polymerases. Among them, Polµ is unique as it can catalyze DNA synthesis upon connection of two non-complementary ends. Here, we demonstrate that this capacity is intrinsic to Polµ, not conferred by other NHEJ factors. To understand the molecular determinants of its specific function in NHEJ, the interaction of human Polµ with DNA has been directly visualized by electromobility shift assay and footprinting assays. Stable interaction with a DNA gap requires the presence of a recessive 5'-P, thus orienting the catalytic domain for primer and nucleotide binding. Accordingly, recognition of the 5'-P is crucial to align the two DNA substrates of the NHEJ reaction. Site-directed mutagenesis demonstrates the relevance of three specific residues (Lys(249), Arg(253) and Arg(416)) in stabilizing the primer strand during end synapsis, allowing a range of microhomology-induced distortions beneficial for NHEJ. Moreover, our results suggest that the Polµ BRCT domain, thought to be exclusively involved in interaction with NHEJ core factors, has a direct role in binding the DNA region neighbor to the 5'-P, thus boosting Polµ-mediated NHEJ reactions.


Asunto(s)
Reparación del ADN por Unión de Extremidades , Proteínas de Unión al ADN/química , ADN Polimerasa Dirigida por ADN/química , ADN/química , ADN/metabolismo , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , ADN Polimerasa Dirigida por ADN/genética , ADN Polimerasa Dirigida por ADN/metabolismo , Humanos , Ligandos , Modelos Moleculares , Mutagénesis Sitio-Dirigida , Unión Proteica , Estructura Terciaria de Proteína
14.
Andes Pediatr ; 95(1): 34-40, 2024 Feb.
Artículo en Español | MEDLINE | ID: mdl-38587342

RESUMEN

Clinical control and monitoring of bilirubin in the neonatal stage are essential to avoid toxicity in the central nervous system. OBJECTIVE: to determine the correlation between transcutaneous bilirubin (TcB) and total serum bilirubin (TSB) levels in newborns ≥ 35 weeks. PATIENTS AND METHOD: observational, cross-sectional, analytical, retrospective study that included 90 neonates of gestational age ≥ 35 weeks with mucocutaneous jaundice who underwent TcB and TSB measurement simultaneously between June 1, 2022, and January 31, 2023. Both variables were compared, determining their correlation. RESULTS: the validity indicators were analyzed, obtaining 100% sensitivity and negative predictive value. The mean of TcB determinations was 14.84 mg/dl ± 2.27 and that of TSB was 13.1 mg/dl ± 2.39. The correlation obtained indicates that both variables are related, which is a direct correlation and, according to the prediction equation, there is an appropriate correlation between them. It was determined that TcB overestimated TSB in 95.56% of the determinations, and underestimated TSB in the rest (4.44%). Simultaneous measurements of TcB and TSB were different in all determinations with a mean difference of 1.72 ± 1.48. CONCLUSIONS: the non-invasive TcB method can be used as an initial screening tool for the neonatal population ≥ 35 weeks, given its adequate sensitivity and negative predictive value.


Asunto(s)
Bilirrubina , Tamizaje Neonatal , Humanos , Recién Nacido , Estudios Transversales , Edad Gestacional , Tamizaje Neonatal/métodos , Estudios Retrospectivos
15.
J Neuroinflammation ; 9: 196, 2012 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-22889139

RESUMEN

BACKGROUND: Microglia are resident brain macrophages that can phagocytose dead, dying or viable neurons, which may be beneficial or detrimental in inflammatory, ischaemic and neurodegenerative brain pathologies. Cell death caused by phagocytosis of an otherwise viable cell is called 'primary phagocytosis' or 'phagoptosis'. Calreticulin (CRT) exposure on the surface of cancer cells can promote their phagocytosis via LRP (low-density lipoprotein receptor-related protein) on macrophages, but it is not known whether this occurs with neurons and microglia. METHODS: We used primary cultures of cerebellar neurons, astrocytes and microglia to investigate the potential role of CRT/LRP phagocytic signalling in the phagocytosis of viable neurons by microglia stimulated with lipopolysaccharide (LPS) or nanomolar concentrations of amyloid-ß peptide1-42 (Aß). Exposure of CRT on the neuronal surface was investigated using surface biotinylation and western blotting. A phagocytosis assay was also developed using BV2 and PC12 cell lines to investigate CRT/LRP signalling in microglial phagocytosis of apoptotic cells. RESULTS: We found that BV2 microglia readily phagocytosed apoptotic PC12 cells, but this was inhibited by a CRT-blocking antibody or LRP-blocking protein (receptor-associated protein: RAP). Activation of primary rat microglia with LPS or Aß resulted in loss of co-cultured cerebellar granule neurons, and this was blocked by RAP or antibodies against CRT or against LRP, preventing all neuronal loss and death. CRT was present on the surface of viable neurons, and this exposure did not change in inflammatory conditions. CRT antibodies prevented microglia-induced neuronal loss when added to neurons, while LRP antibodies prevented neuronal loss when added to the microglia. Pre-binding of CRT to neurons promoted neuronal loss if activated microglia were added, but pre-binding of CRT to microglia or both cell types prevented microglia-induced neuronal loss. CONCLUSIONS: CRT exposure on the surface of viable or apoptotic neurons appears to be required for their phagocytosis via LRP receptors on activated microglia, but free CRT can block microglial phagocytosis of neurons by acting on microglia. Phagocytosis of CRT-exposing neurons by microglia can be a direct cause of neuronal death during inflammation, and might therefore contribute to neurodegeneration and be prevented by blocking the CRT/LRP pathway.


Asunto(s)
Péptidos beta-Amiloides/toxicidad , Calreticulina/fisiología , Proteínas Relacionadas con Receptor de LDL/fisiología , Lipopolisacáridos/toxicidad , Microglía/fisiología , Neuronas/fisiología , Fragmentos de Péptidos/toxicidad , Fagocitosis/fisiología , Transducción de Señal/fisiología , Animales , Supervivencia Celular/fisiología , Células Cultivadas , Técnicas de Cocultivo , Proteínas Relacionadas con Receptor de LDL/antagonistas & inhibidores , Células PC12 , Ratas
16.
Proc Natl Acad Sci U S A ; 106(38): 16203-8, 2009 Sep 22.
Artículo en Inglés | MEDLINE | ID: mdl-19805281

RESUMEN

DNA polymerase mu (Polmu) is a family X member implicated in DNA repair, with template-directed and terminal transferase (template-independent) activities. It has been proposed that the terminal transferase activity of Polmu can be specifically required during non-homologous end joining (NHEJ) to create or increase complementarity of DNA ends. By site-directed mutagenesis in human Polmu, we have identified a specific DNA ligand residue (Arg(387)) that is responsible for its limited terminal transferase activity compared to that of human TdT, its closest homologue (42% amino acid identity). Polmu mutant R387K (mimicking TdT) displayed a large increase in terminal transferase activity, but a weakened interaction with ssDNA. That paradox can be explained by the regulatory role of Arg(387) in the translocation of the primer from a non-productive E:DNA complex to a productive E:DNA:dNTP complex in the absence of a templating base, which is probably the rate limiting step during template-independent synthesis. Further, we show that the Polmu switch from terminal transferase to templated insertions in NHEJ reactions is triggered by recognition of a 5'-P at a second DNA end, whose 3'-protrusion could provide a templating base to facilitate such a special "pre-catalytic translocation step." These studies shed light on the mechanism by which a rate-limited terminal transferase activity in Polmu could regulate the balance between accuracy and necessary efficiency, providing some variability during NHEJ.


Asunto(s)
Reparación del ADN , ADN Polimerasa Dirigida por ADN/metabolismo , Transferasas/metabolismo , Secuencia de Aminoácidos , Sustitución de Aminoácidos , Arginina/genética , Arginina/metabolismo , Catálisis , Dominio Catalítico/genética , Roturas del ADN de Doble Cadena , Daño del ADN , ADN Polimerasa Dirigida por ADN/química , ADN Polimerasa Dirigida por ADN/genética , Histidina/genética , Histidina/metabolismo , Humanos , Modelos Moleculares , Datos de Secuencia Molecular , Mutagénesis Sitio-Dirigida , Unión Proteica , Estructura Terciaria de Proteína , Homología de Secuencia de Aminoácido , Especificidad por Sustrato , Transferasas/química , Transferasas/genética
17.
Artículo en Inglés | MEDLINE | ID: mdl-35270750

RESUMEN

The purpose of this study was to show how continuous exercise affects the basal values of biochemical and hematological parameters in elite athletes. A total of 14,010 samples (male = 8452 and female = 5558 (March 2011-March 2020)) from 3588 elite athletes (male = 2258 and female = 1330, mean age 24.9 ± 6.9 vs. 24.1 ± 5.5 years, respectively) from 32 sport modalities, were studied over 9 years to check the variation of basal biochemical and hematological parameter values. There were differences seen in the basal values of creatine kinase (CK), urea, creatinine, aspartate transaminase (AST), alanine aminotransferase (ALT), lactate dehydrogenase (LDH), potassium, total bilirubin, and eosinophil percentage compared to reference population data. However, other analytes showed narrow ranges of variation like glucose, total protein, albumin, sodium, hemoglobin, mean cell volume (MCV), and platelet count. Exercise produces changes in biochemical and hematological basal values of athletes compared to the general population, with the greatest variation in CK, but AST, ALT, LDH, potassium, and total bilirubin (TBil) show high values in serum, only with a wider distribution of values. The data here reflects the effect of exercise on biochemical and hematological parameter baseline ranges in elite athletes. As clinical laboratories use reference intervals to validate clinical reports, these "pseudo" reference intervals should be used when validating laboratory reports.


Asunto(s)
Atletas , Creatina Quinasa , Adolescente , Adulto , Alanina Transaminasa , Aspartato Aminotransferasas , Bilirrubina , Femenino , Humanos , L-Lactato Deshidrogenasa , Masculino , Potasio , Valores de Referencia , Adulto Joven
18.
Afr Health Sci ; 22(1): 598-601, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36032454

RESUMEN

Background: Sickle cell disease (SCD) is an inherited hemoglobinopathy characterized by the presence of hemoglobin S in red blood cells. This polymerizes, distorting the red blood cells, which occlude the microcirculation and have a shorter halflife, giving rise to a chronic hemolytic anemia. This anemia is worsened by parvovirus B19, as it compromises the erythroid precursor, causing a decrease in erythrocyte production. These patients sometimes present with splenic sequestration, characterized by acute blood entrapment in the spleen, with clinical signs of hypovolemic shock. The simultaneous appearance of both leads to an extremely severe situation that requires urgent action. Objective: To describe the case of a patient with SCD and splenic sequestration, in which the suspicion of concomitant aplastic crisis affected her prognosis. Clinical case: 3-year-old girl with homozygous SCD, presenting with fever, cough, vomiting and pain in the lower limbs. Upon arrival, hemodynamic instability, mucocutaneous pallor, and splenomegaly were observed. Hemogram on admission showed an acute drop in haemoglobin level with reticulocytopenia. Splenic sequestration was suspected, along with aplastic crisis, so she received a blood transfusion, subsequently showing progressive improvement. Human parvovirus B19-specific IgM and IgG antibodies were detected in the serum. Conclusion: Patients with SCD and parvovirus B19 infection must be closely observed for splenomegaly since an early identification of an enlarging spleen can lead to an early diagnosis of this complication.


Asunto(s)
Anemia de Células Falciformes , Eritema Infeccioso , Infecciones por Parvoviridae , Parvovirus B19 Humano , Anticuerpos Antivirales , Niño , Preescolar , Femenino , Humanos , Inmunoglobulina M , Esplenomegalia
19.
Andes Pediatr ; 93(2): 167-173, 2022 Apr.
Artículo en Español | MEDLINE | ID: mdl-35735294

RESUMEN

INTRODUCTION: During the SARS-CoV-2 pandemic, efforts have focused on trying to identify the routes of transmis sion of the virus, characterize its symptoms and signs, and investigate the best diagnostic and thera peutic methods. There are fewer published data and series in the pediatric population than in adults. OBJECTIVE: To analyze the clinical and epidemiological characteristics in children under 16 years of age diagnosed with SARS-CoV-2. PATIENTS AND METHOD: Descriptive study carried out on children who underwent SARS-CoV-2 RNA testing due to compatible symptoms, close contact, or requiring hospitalization or surgery, in the Emergency Department of a hospital in Madrid, Spain. 30 variables were collected including epidemiological data, symptoms, and signs of infection. RESULTS: Out of 1378 patients, 12% were positive (165). There was a higher proportion of patients of North African origin in the positive group than in the negative one (p < 0.01). Of all patients, 35.6% reported close contact with a confirmed case, which was more frequent in the positive group. 75.8% of the positive patients had some symptoms, most frequently fever, runny nose, and cough, followed by digesti ve symptoms. There was one case of COVID-19 pneumonia and two patients with MIS-C, one of which had SARS-CoV-2 infection. Eight of the positive patients (4.8%) required hospitalization due to SARS-CoV-2 infection. CONCLUSION: Although SARS-CoV-2 infection is milder in the pediatric population, almost 5% will require hospitalization. No close contact was identified in a high percen tage of patients (61%). Further studies are needed at all levels of care to characterize the infection in children and adolescents.


Asunto(s)
COVID-19 , Adolescente , Adulto , COVID-19/complicaciones , COVID-19/diagnóstico , COVID-19/epidemiología , Niño , Humanos , Pandemias , ARN Viral , SARS-CoV-2 , Síndrome de Respuesta Inflamatoria Sistémica
20.
Endocrinol Diabetes Nutr ; 69(10): 810-815, 2022 Dec.
Artículo en Español | MEDLINE | ID: mdl-35261966

RESUMEN

Introduction: ß-pancreatic cells are susceptible to SARS-CoV-2 infection and replication; this could lead to infection-related diabetes or precipitate the onset of type 1 diabetes. This study aimed to determine the severity at diagnosis, analyzing clinical and epidemiological features at onset in children under 16 years of age in the context of the SARS-CoV-2 pandemic. Material and methods: A retrospective observational multicenter study was carried out in 7 hospitals of the public health network located in the south of our community. The severity at debut is compared with that of the two previous years (2018 and 2019). The level of statistical significance is set at P < .05. Results: In 2020, 61 patients were diagnosed at the 7 hospital centres. The mean age was 10.1 years (SD: 2.6), 50.8% were older than 10 years. The clinical profile at diagnosis was ketoacidosis in 52.5% compared to 39.5% and 26.5% in the previous two years (P < .01). The mean pH (7.24 vs 7.30 / 7.30) and excess of bases (-11.9 vs -7.43 / -7.9) was lower than in the previous two years, and the glycated haemoglobin higher (11.9 vs 11 / 10.6)%, p < 0.05. At least 10% of the patients had a positive history of SARS-CoV-2 infection. Conclusions: There has been an increase in the frequency of diabetic ketoacidosis in type 1 diabetes onset during the first year of the COVID-19 pandemic.

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