Plan de mejora para el cumplimiento de la NTP ISO/IEC 17025:2017 en un laboratorio de ensayos físicos mecánicos

La presente investigación denominada “Plan de mejora para el cumplimiento de la NTP ISO/IEC 17025:2017 en un laboratorio de ensayos físicos mecánicos”, tuvo como objetivo desarrollar un plan de mejora para lograr el nivel de cumplimiento de la Norma NTP ISO/IEC 17025:2017 y lograr la acreditación del Laboratorio de ensayos físicos, siendo una investigación de tipo aplicativa ya que busca conocimientos adquiridos a partir de una investigación y de la práctica sistemática. Teniendo como muestra los colaboradores del área de laboratorio. Para la recolección de la información se utilizó la técnica de la observación, análisis documental, encuesta y los instrumentos aplicados fueron la ficha de observación y el checklist, el cual estaba basado en los requerimientos de la Norma NTP ISO/IEC 17025:2017. En los resultados se determinó que el laboratorio realiza ensayos físicos y algunos análisis químicos entre otros, teniendo a su disposición los equipos y ambientes adecuados para la ejecución de sus ensayos. En la evaluación de los requisitos que establece la Norma, se identificó que el Laboratorio presenta un nivel de cumplimiento general de la norma del 57.2%. Se realizó un plan de mejora de implementación con el objetivo de que el laboratorio identifique y realice los procedimientos necesarios para el proceso de implementación y una futura acreditación de la Norma ISO/NTP 17025:2017

proMetalloproteinase-10 is associated with brain damage and clinical outcome in acute ischemic stroke

BACKGROUND: Matrix metalloproteinases (MMPs) mediate tissue injury during stroke but also neurovascular remodeling and we have shown that MMP-10 is involved in atherothrombosis. OBJECTIVE: The purpose of this study was to examine the relationship between proMMP-10 and clinical outcome, assessing inflammatory and proteolytic markers, in patients with acute ischemic stroke. METHODS: We prospectively studied 76 patients with ischemic stroke treated with tPA within the first 3 h from symptom onset, compared with 202 non-tPA-treated ischemic stroke patients and 83 asymptomatic subjects. Stroke severity was assessed with the National Institutes of Health Stroke Scale (NIHSS). Hemorrhagic transformation (HT) and severe brain edema were diagnosed by cranial CT. Good functional outcome was defined as a modified Rankin scale score </= 2 at 90 days. Serum levels of MMP-9, proMMP-10, TIMP-1, tumor necrosis factor-alpha (TNFalpha), interleukin-6 and cellular fibronectin were measured at admission. The effect of TNFalpha on endothelial proMMP-10 was assessed in vitro. RESULTS: Serum proMMP-10 concentration in ischemic stroke patients, non-treated or treated with t-PA, which was higher than age-matched healthy subjects (P < 0.0001), was independently associated with higher infarct volume, severe brain edema, neurological deterioration and poor functional outcome at 3 months (all P < 0.05), but not with HT. proMMP-10 levels were also independently and positively associated with circulating levels of TNFalpha (P < 0.0001), which induced its endothelial expression in vitro, both mRNA and protein. MMP-9, however, was only associated with HT and severe edema (all P < 0.05). CONCLUSIONS: Increased serum proMMP-10 after acute ischemic stroke, associated with TNFalpha, is a new marker of brain damage and poor outcome

Interleukin-10 facilitates the selection of patients for systemic thrombolysis

Background: Clinical-Diffusion mismatch (CDM; NIHSS score ≥8 & DWI lesion volume ≤25 mL) and Perfusion-Diffusion mismatch (PDM; difference >20% between initial DWI and MTT lesion volumes) have been proposed as surrogates for ischemic brains that are at risk of infarction. However, their utility to improve the selection of patients for thrombolytic treatment remains controversial. Our aim was to identify molecular biomarkers that can be used with neuroimaging to facilitate the selection of ischemic stroke patients for systemic thrombolysis. Methods: We prospectively studied 595 patients with ischemic stroke within 12 h of the stroke onset. A total of 184 patients received thrombolytic treatment according to the SITS-MOST criteria. DWI and MTT volumes were measured at admission. The main outcome variable was good functional outcome at 3 months (modified Rankin scale <3). Serum levels of glutamate (Glu), IL-10, TNF-α, IL-6, NSE, and active MMP-9 also were determined at admission. Results: Patients treated with t-PA who presented with PDM had higher IL-10 levels at admission (p < 0.0001). In contrast, patients with CDM had higher levels of IL-10 (p < 0.0001) as well as Glu and TNF-α (all p < 0.05) and lower levels of NSE and active MMP-9 (all p < 0.0001). IL-10 ≥ 30 pg/mL predicts good functional outcome at 3 months with a specificity of 88% and a sensitibity of 86%. IL-10 levels ≥30 pg/mL independently in both patients with PDM (OR, 18.9) and CDM (OR, 7.5), after an adjustment for covariates. Conclusions: Serum levels of IL-10 facilitate the selection of ischemic stroke patients with CDM and PDM for systemic thrombolysis

Nuclear WRAP53 promotes neuronal survival and functional recovery after stroke

Failure of neurons to efficiently repair DNA double-strand breaks (DSBs) contributes to cerebral damage after stroke. However, the molecular machinery that regulates DNA repair in this neurological disorder is unknown. Here, we found that DSBs in oxygen/glucose-deprived (OGD) neurons spatiotemporally correlated with the up-regulation of WRAP53 (WD40-encoding p53-antisense RNA), which translocated to the nucleus to activate the DSB repair response. Mechanistically, OGD triggered a burst in reactive oxygen species that induced both DSBs and translocation of WRAP53 to the nucleus to promote DNA repair, a pathway that was confirmed in an in vivo mouse model of stroke. Noticeably, nuclear translocation of WRAP53 occurred faster in OGD neurons expressing the Wrap53 human nonsynonymous single-nucleotide polymorphism (SNP) rs2287499 (c.202C>G). Patients carrying this SNP showed less infarct volume and better functional outcome after stroke. These results indicate that WRAP53 fosters DNA repair and neuronal survival to promote functional recovery after stroke

Hyperthermia in human ischemic and hemorrhagic stroke: similar outcome, different mechanisms

Hyperthermia is a predictor of poor outcome in ischemic (IS) and intracerebral hemorrhagic (ICH) stroke. Our aim was to study the plausible mechanisms involved in the poor outcome associated to hyperthermia in stroke. We conducted a case-control study including patients with IS (n = 100) and ICH (n = 100) within the first 12 hours from symptom onset. Specifically, IS and ICH patients were consecutively included into 2 subgroups, according to the highest body temperature within the first 24 hours: Tmax 2) at 3 months. Serum levels of glutamate and active MMP-9 were measured at admission. Our results showed that Tmax ≥37.5°C within the first 24 hours was independently associated with poor outcome in both IS (OR, 12.43; 95% CI, 3.73-41.48; p<0.0001) and ICH (OR, 4.29; 95% CI, 1.32-13.91; p = 0.015) after adjusting for variables with a proven biological relevance for outcome. However, when molecular markers levels were included in the logistic regression model, we observed that glutamate (OR, 1.01; 95% CI, 1.00-1.02; p = 0.001) and infarct volume (OR, 1.06; 95% CI, 1.01-1.10; p = 0.015) were the only variables independently associated to poor outcome in IS, and active MMP-9 (OR, 1.04; 95% CI, 1.00-1.08; p = 0.002) and National Institute of Health Stroke Scale (NIHSS) at admission (OR, 1.29; 95% CI, 1.13-1.49; p<0.0001) in ICH. In conclusion, these results suggest that although the outcome associated to hyperthermia is similar in human IS and ICH, the underlying mechanisms may be different

Antihyperthermic treatment decreases perihematomal hypodensity

OBJECTIVE: To investigate the effect on perihematomal hypodensity and outcome of a decrease in body temperature in the first 24 hours in patients with intracerebral hemorrhage (ICH). METHODS: In this retrospective study on a prospectively registered database, among the 1,100 patients, 795 met all the inclusion criteria. Temperature variations in the first 24 hours and perihematomal hypodensity (PHHD) were recorded. Patients >/=37.5 degrees C were treated with antihyperthermic drugs for at least 48 hours. The main objective was to determine the association among temperature variation, PHHD, and outcome at 3 months. RESULTS: The decrease in temperature in the first 24 hours increased the possibility of good outcome 11-fold. Temperature decrease, lower PHHD volume, and a good outcome were observed in 31.8% of the patients who received antihyperthermic treatment. CONCLUSION: The administration of early antihyperthermic treatment in patients with spontaneous ICH with a basal axillary temperature >/=37.5 degrees C resulted in good outcome in a third of the treated patients

Influence of Sex on Stroke Prognosis: A Demographic, Clinical, and Molecular Analysis

Identifying the complexities of the effect of sex on stroke risk, etiology, and lesion progression may lead to advances in the treatment and care of ischemic stroke (IS) and non-traumatic intracerebral hemorrhage patients (ICH). We studied the sex-related discrepancies on the clinical course of patients with IS and ICH, and we also evaluated possible molecular mechanisms involved. The study's main variable was the patient's functional outcome at 3-months. Logistic regression models were used in order to study the influence of sex on different inflammatory, endothelial and atrial dysfunction markers. We recruited 5,021 patients; 4,060 IS (54.8% male, 45.2% female) and 961 ICH (57.1% male, 42.9% female). Women were on average 5.7 years older than men (6.4 years in IS, 5.1 years in ICH), and more likely to have previous poor functional status, to suffer atrial fibrillation and to be on anticoagulants. IS patients showed sex-related differences at 3-months regarding poorer outcome (55.6% women, 43.6% men, p < 0.0001), but this relationship was not found in ICH (56.8% vs. 61.9%, p = 0.127). In IS, women had higher levels of NT-proBNP and 3-months worse outcome in both cardioembolic and non-cardioembolic stroke patients. Stroke patients showed sex-related differences in pre-hospital data, clinical variables and molecular markers, but only IS patients presented independent sex-related differences in 3-months poor outcome and mortality. There was a relationship between the molecular marker of atrial dysfunction NT-proBNP and worse functional outcome in women, resulting in a possible indicator of increased dysfunction

Intra- and extra-hospital improvement in ischemic stroke patients: influence of reperfusion therapy and molecular mechanisms

Neuroprotective treatments in ischemic stroke are focused to reduce the pernicious effect of excitotoxicity, oxidative stress and inflammation. However, those cellular and molecular mechanisms may also have beneficial effects, especially during the late stages of the ischemic stroke. The objective of this study was to investigate the relationship between the clinical improvement of ischemic stroke patients and the time-dependent excitotoxicity and inflammation. We included 4295 ischemic stroke patients in a retrospective study. The main outcomes were intra and extra-hospital improvement. High glutamate and IL-6 levels at 24 hours were associated with a worse intra-hospital improvement (OR:0.993, 95%CI: 0.990-0.996 and OR:0.990, 95%CI: 0.985-0.995). High glutamate and IL-6 levels at 24 hours were associated with better extra-hospital improvement (OR:1.13 95%CI, 1.07-1.12 and OR:1.14, 95%CI, 1.09-1.18). Effective reperfusion after recanalization showed the best clinical outcome. However, the long term recovery is less marked in patients with an effective reperfusion. The variations of glutamate and IL6 levels in the first 24 hours clearly showed a relationship between the molecular components of the ischemic cascade and the clinical outcome of patients. Our findings suggest that the rapid reperfusion after recanalization treatment blocks the molecular response to ischemia that is associated with restorative processes

Regulatory T cells participate in the recovery of ischemic stroke patients

BACKGROUND: Recent preclinical studies have shown that regulatory T cells (Treg) play a key role in the immune response after ischemic stroke (IS). However, the role of Treg in human acute IS has been poorly investigated. Our aim was to study the relationship between circulating Treg and outcome in human IS patients. METHODS: A total of 204 IS patients and 22 control subjects were recruited. The main study variable was good functional outcome at 3 months (modified Rankin scale </=2) considering infarct volume, Early Neurological Deterioration (END) and risk of infections as secondary variables. The percentage of circulating Treg was measured at admission, 48, 72 h and at day 7 after stroke onset. RESULTS: Circulating Treg levels were higher in IS patients compared to control subjects. Treg at 48 h were independently associated with good functional outcome (OR, 3.5; CI: 1.9-7.8) after adjusting by confounding factors. Patients with lower Treg at 48 h showed higher frequency of END and risk of infections. In addition, a negative correlation was found between circulating Treg at 48 h (r = - 0.414) and 72 h (r = - 0.418) and infarct volume. CONCLUSIONS: These findings suggest that Treg may participate in the recovery of IS patients. Therefore, Treg may be considered a potential therapeutic target in acute ischemic stroke

The human Tp53 Arg72Pro polymorphism explains different functional prognosis in stroke

Poor prognosis after ischemic stroke or intracerebral hemorrhage is linked to a particular polymorphism in the human gene encoding p53