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Novel Pannexin-1-Coupled Signaling Cascade Involved in the Control of Endothelial Cell Function and NO-Dependent Relaxation
(2021)
Mauricio A. Lillo
;
Pablo S. Gaete
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Mariela Puebla
;
Pía C. Burboa
;
Inés Poblete
<jats:p>Deletion of pannexin-1 (Panx-1) leads not only to a reduction in endothelium-derived hyperpolarization but also to an increase in NO-mediated vasodilation. Therefore, we evaluated the participation of Panx-1-formed channels in the control of membrane potential and [Ca2+]i of endothelial cells. Changes in NO-mediated vasodilation, membrane potential, superoxide anion (O2⋅–) formation, and endothelial cell [Ca2+]i were analyzed in rat isolated mesenteric arterial beds and primary cultures of mesenteric endothelial cells. Inhibition of Panx-1 channels with probenecid (1 mM) or the Panx-1 blocking peptide 10Panx (60 μM) evoked an increase in the ACh (100 nM)-induced vasodilation of KCl-contracted mesenteries and in the phosphorylation level of endothelial NO synthase (eNOS) at serine 1177 (P-eNOSS1177) and Akt at serine 473 (P-AktS473). In addition, probenecid or 10Panx application activated a rapid, tetrodotoxin (TTX, 300 nM)-sensitive, membrane potential depolarization and [Ca2+]i increase in endothelial cells. Interestingly, the endothelial cell depolarization was converted into a transient spike after removing Ca2+ ions from the buffer solution and in the presence of 100 μM mibefradil or 10 μM Ni2+. As expected, Ni2+ also abolished the increment in [Ca2+]i. Expression of Nav1.2, Nav1.6, and Cav3.2 isoforms of voltage-dependent Na+ and Ca2+ channels was confirmed by immunocytochemistry. Furthermore, the Panx-1 channel blockade was associated with an increase in O2⋅– production. Treatment with 10 μM TEMPOL or 100 μM apocynin prevented the increase in O2⋅– formation, ACh-induced vasodilation, P-eNOSS1177, and P-AktS473 observed in response to Panx-1 inhibition. These findings indicate that the Panx-1 channel blockade triggers a novel complex signaling pathway initiated by the sequential activation of TTX-sensitive Nav channels and Cav3.2 channels, leading to an increase in NO-mediated vasodilation through a NADPH oxidase-dependent P-eNOSS1177, which suggests that Panx-1 may be involved in the endothelium-dependent control of arterial blood pressure.</jats:p>
7Scopus© Citations 13
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Parámetros hematológicos y biomarcadores predictores de gravedad en Síndrome Inflamatorio Pediátrico Multisistémico asociado a SARS-CoV-2
(2021)
Patricia Verdugo
;
Patricia Álvarez
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Patricia Aroca
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Vicente Enrique Montes-nogales
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POLI HARLOWE, MARIA CECILIA BERTA
<jats:p>El síndrome inflamatorio multisistémico pediátrico asociado a SARS-CoV-2 (MIS-C) se caracteriza por un estado hiperinflamatorio producto de una tormenta de citoquinas, evidenciado en alteraciones del laboratorio hematológico y proteínas de fase aguda.Objetivo: Describir las características clínicas y de laboratorio de pacientes hospitalizados por MIS-C e identificar marcadores predictores de gravedad.Pacientes y Método: Estudio retrospectivo de 32 pacientes. El grupo se dividió en crítico y no crítico según presentación clínica y tipo de terapia utilizada. En ellos se estudiaron aspectos clínicos y de laboratorio que incluyeron hemograma completo, pruebas de coagulación y biomarcadores. Resultados: 18/32 hombres, mediana de edad 6,8 años. Las manifestaciones más frecuentes fueron cardiovasculares (84,3%), digestivas (84%) y mucocutáneas (59%). El grupo de los críticos incluyó 15 pacientes, 12 hombres con mediana de edad de 8,9 años y los no críticos 17 pacientes; 6 hombres, con mediana de edad de 5,4 años. Los parámetros de laboratorio al ingreso en el grupo global mostraron aumento de la proteína C reactiva, dímero-D, leucocitos, neutrófilos, ferritina y fibrinógeno. La albúmina y la natremia en cambio se encontraban disminuidas. El grupo crítico se caracterizó por tener al ingreso: trombocitopenia, hipoalbuminemia, prolongación del tiempo de protrombina y elevación de la ferritina. Al deterioro hubo acentuación de la trombocitopenia, ascenso mayor de la proteína C reactiva junto a elevación de los neutrófilos.Conclusión: El hemograma, la proteína C reactiva y la albuminemia al ingreso resultaron ser de alto valor en la identificación de pacientes con riesgo de agravamiento clínico.</jats:p>
20Scopus© Citations 10
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Validation of the simplified modified Rankin scale for stroke trials: Experience from the ENCHANTED alteplase-dose arm
(2020)
Xiaoying Chen
;
Jingwei Li
;
Craig S Anderson
;
Richard I Lindley
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Maree L Hackett
<jats:sec><jats:title>Background and aims</jats:title><jats:p> The structured, simplified modified Rankin scale questionnaire (smRSq) may increase reliability over the interrogative approach to scoring the modified Rankin scale (mRS) in acute stroke research and practice. During the conduct of the alteplase-dose arm of the international ENhanced Control of Hypertension ANd Thrombolysis StrokE stuDy (ENCHANTED), we had an opportunity to compare each of these approaches to outcome measurement. </jats:p></jats:sec><jats:sec><jats:title>Methods</jats:title><jats:p> Baseline demographic data were recorded together with the National Institutes of Health Stroke Scale (NIHSS). Follow-up measures obtained at 90 days included mRS, smRSq, and the 5-Dimension European Quality of life scale (EQ-5D). Agreements between smRSq and mRS were assessed with the Kappa statistic. Multiple logistic regression was used to identify baseline predictors of Day 90 smRSq and mRS scores. Treatment effects, based on Day 90 smRSq/mRS scores, were tested in logistic and ordinal logistic regression models. </jats:p></jats:sec><jats:sec><jats:title>Results</jats:title><jats:p> SmRSq and mRS scores had good agreement (weighted Kappa 0.79, 95% confidence interval (CI) 0.78–0.81), while variables of age, atrial fibrillation, diabetes mellitus, pre-morbid mRS (1 vs. 0), baseline NIHSS scores, and imaging signs of cerebral ischemia, similarly predicted their scores. Odds ratios for death or disability, and ordinal shift, 90-day mRS scores using smRSq were 1.05 (95% CI 0.91–1.20; one-sided P = 0.23 for non-inferiority) and 0.98 (95% CI 0.87–1.11; P = 0.02 for non-inferiority), similar to those using mRS. </jats:p></jats:sec><jats:sec><jats:title>Conclusions</jats:title><jats:p> This study demonstrates the utility of the smRSq in a large, ethnically diverse clinical trial population. Scoring of the smRSq shows adequate agreement with the standard mRS, thus confirming it is a reliable, valid, and useful alternative measure of functional status after acute ischemic stroke. </jats:p></jats:sec><jats:sec><jats:title>Clinical Trial registration</jats:title><jats:p> URL: http://www.clinicaltrials.gov . Unique identifier: NCT01422616. </jats:p></jats:sec>
Scopus© Citations 9 7
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Prognostic significance of early urinary catheterization after acute stroke: Secondary analyses of the international HeadPoST trial
(2020)
Menglu Ouyang
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Laurent Billot
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Lili Song
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Xia Wang
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Christine Roffe
<jats:sec><jats:title>Background</jats:title><jats:p> An indwelling urinary catheter (IUC) is often inserted to manage bladder dysfunction, but its impact on prognosis is uncertain. We aimed to determine the association of IUC use on clinical outcomes after acute stroke in the international, multi-center, cluster crossover, Head Positioning in Acute Stroke Trial (HeadPoST). </jats:p></jats:sec><jats:sec><jats:title>Methods</jats:title><jats:p> Data were analyzed on HeadPoST participants (n = 11,093) randomly allocated to the lying-flat or sitting-up head position. Binomial, logistic regression, hierarchical mixed models were used to determine associations of early insertion of IUC within seven days post-randomization and outcomes of death or disability (defined as “poor outcome,” scores 3–6 on the modified Rankin scale) and any urinary tract infection at 90 days with adjustment of baseline and post-randomization management covariates. </jats:p></jats:sec><jats:sec><jats:title>Results</jats:title><jats:p> Overall, 1167 (12%) patients had an IUC, but the frequency and duration of use varied widely across patients in different regions. IUC use was more frequent in older patients, and those with vascular comorbidity, greater initial neurological impairment (on the National Institutes of Health Stroke Scale), and intracerebral hemorrhage as the underlying stroke type. IUC use was independently associated with poor outcome (adjusted odds ratio (aOR): 1.40, 95% confidence interval (CI): 1.13–1.74), but not with urinary tract infection after adjustment for antibiotic treatment and stroke severity at hospital separation (aOR: 1.13, 95% CI: 0.59–2.18). The number exposed to IUC for poor outcome was 13. </jats:p></jats:sec><jats:sec><jats:title>Conclusions</jats:title><jats:p> IUC use is associated with a poor outcome after acute stroke. Further studies are required to inform appropriate use of IUC. </jats:p></jats:sec>
Scopus© Citations 4 3
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Breaking the breach in Latin America: A pilot study of mechanical thrombectomy in the public healthcare system in Chile
(2020)
Rodrigo Rivera
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Cristian Amudio
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Enzo Brunetti
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Pascual Catalan
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Juan Gabriel Sordo
<jats:sec><jats:title>Background</jats:title><jats:p> Mechanical Thrombectomy (MT) is the standard of care for treatment of large vessel occlusion stroke. Until the beginning of 2020 MT was not funded nor widely implemented at the public healthcare level in Chile. </jats:p></jats:sec><jats:sec><jats:title>Objective</jats:title><jats:p> To describe the results of a pilot program created to provide access to public MT in Santiago - Chile. </jats:p></jats:sec><jats:sec><jats:title>Methods</jats:title><jats:p> Analysis from a prospectively collected database of MT cases performed between September 2017 and September 2019 in one center. A stroke network was developed with a single MT capable stroke center and five primary stroke centers. The primary efficacy endpoint was the rate of functional independence (mRS 0-2) at 90 days. Successful reperfusion was defined as 2 b-3 according to the thrombolysis in cerebral infarction scale. Safety outcomes include the rates of symptomatic intracranial hemorrhage and 90-day mortality. </jats:p></jats:sec><jats:sec><jats:title>Results</jats:title><jats:p> A total of 100 patients were treated over the study period. Their mean age was 62.8 ± 11.8 years and median baseline National Institute of Health Stroke Scale (NIHSS) measurement was 17. Seventy-seven percent of the patients received intra venous thrombolysis. Successful reperfusion was achieved in 95% of the cases. NIHSS at 24 hours showed a median drop of 7 points from baseline (p < 0.00001) and 50% of the follow-up patients were functionally independent at 90 days. Symptomatic Intracerebral hemorrhage occurred in 5% of the patients and 90-day all case mortality was 11%. </jats:p></jats:sec><jats:sec><jats:title>Conclusions</jats:title><jats:p> We demonstrated the feasibility of a publicly funded MT program in Chile, with similar results as other international randomized control trials. </jats:p></jats:sec>
Scopus© Citations 10 4
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Structural brain abnormalities in schizophrenia in adverse environments: examining the effect of poverty and violence in six Latin American cities
(2020)
Nicolas A. Crossley
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Andre Zugman
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Francisco Reyes-Madrigal
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Leticia S. Czepielewski
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Mariana N. Castro
<jats:title>Summary</jats:title><jats:sec id="S0007125020001439_sec_a1"><jats:title>Background</jats:title><jats:p>Social and environmental factors such as poverty or violence modulate the risk and course of schizophrenia. However, how they affect the brain in patients with psychosis remains unclear.</jats:p></jats:sec><jats:sec id="S0007125020001439_sec_a2"><jats:title>Aims</jats:title><jats:p>We studied how environmental factors are related to brain structure in patients with schizophrenia and controls in Latin America, where these factors are large and unequally distributed.</jats:p></jats:sec><jats:sec id="S0007125020001439_sec_a3" sec-type="methods"><jats:title>Method</jats:title><jats:p>This is a multicentre study of magnetic resonance imaging in patients with schizophrenia and controls from six Latin American cities. Total and voxel-level grey matter volumes, and their relationship with neighbourhood characteristics such as average income and homicide rates, were analysed with a general linear model.</jats:p></jats:sec><jats:sec id="S0007125020001439_sec_a4" sec-type="results"><jats:title>Results</jats:title><jats:p>A total of 334 patients with schizophrenia and 262 controls were included. Income was differentially related to total grey matter volume in both groups (<jats:italic>P</jats:italic> = 0.006). Controls showed a positive correlation between total grey matter volume and income (<jats:italic>R</jats:italic> = 0.14, <jats:italic>P</jats:italic> = 0.02). Surprisingly, this relationship was not present in patients with schizophrenia (<jats:italic>R</jats:italic> = −0.076, <jats:italic>P</jats:italic> = 0.17). Voxel-level analysis confirmed that this interaction was widespread across the cortex. After adjusting for global brain changes, income was positively related to prefrontal cortex volumes only in controls. Conversely, the hippocampus in patients with schizophrenia, but not in controls, was relatively larger in affluent environments. There was no significant correlation between environmental violence and brain structure.</jats:p></jats:sec><jats:sec id="S0007125020001439_sec_a5" sec-type="conclusions"><jats:title>Conclusions</jats:title><jats:p>Our results highlight the interplay between environment, particularly poverty, and individual characteristics in psychosis. This is particularly important for harsh environments such as low- and middle-income countries, where potentially less brain vulnerability (less grey matter loss) is sufficient to become unwell in adverse (poor) environments.</jats:p></jats:sec>
Scopus© Citations 10 1
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Higher Prevalence of Extended-Spectrum Cephalosporin-Resistant Enterobacterales in Dogs Attended for Enteric Viruses in Brazil Before and After Treatment with Cephalosporins
(2021)
Marília Salgado-Caxito
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Andrea I. Moreno-Switt
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Antonio Carlos Paes
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Carlos Shiva
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MUNITA SEPULVEDA, JOSE MANUEL
<jats:p>The extensive use of antibiotics is a leading cause for the emergence and spread of antimicrobial resistance (AMR) among dogs. However, the impact of using antibiotics to treat viral infections on AMR remains unknown. In this study, we compared the prevalence of extended-spectrum cephalosporin-resistant Enterobacterales (ESCR-E) between dogs with a suspected infection of canine parvovirus (CPV) and canine distemper (CDV) before and after treatment with third-generation cephalosporins. We found a higher prevalence of ESCR-E faecal carriage in dogs suspected of CPV (37%) and CDV (15%) compared to dogs with noninfectious pathologies (9%) even prior to the start of their treatment. A 7-day course of ceftriaxone or ceftiofur administrated to CPV and CDV-suspected dogs substantially increased their ESCR-E faecal carriage during treatment (85% for CPV and 57% for CDV), and 4 weeks after the treatment ended (89% for CPV and 60% for CDV) when dogs were back in their households. Most of the observed resistance was carried by ESCR-E. coli carrying blaCTX-M genes. Our results suggest the need to optimize prophylactic antibiotic therapy in dogs treated for a suspected viral infection to prevent ESCR-E emergence and spread in the community.</jats:p>
5Scopus© Citations 15
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Could Subtle Obstetrical Brachial Plexus Palsy Be Related to Unilateral B Glenoid Osteoarthritis?
(2021)
Alexandre Lädermann
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Hugo Bothorel
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Philippe Collin
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Bassem Elhassan
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Luc Favard
<jats:p>Background: Several factors associated with B glenoid are also linked with obstetrical brachial plexus palsy (OBPP). The purpose of this observational study was to determine the incidence of OBPP risk factors in type B patients. Methods: A cohort of 154 patients (68% men, 187 shoulders) aged 63 ± 17 years with type B glenoids completed a questionnaire comprising history of perinatal characteristics related to OBPP. A literature review was performed following the Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) to estimate the incidence of OBPP risk factors in the general population. Results: Twenty-seven patients (18%) reported one or more perinatal OBPP risk factors, including shoulder dystocia (n = 4, 2.6%), macrosomia >4 kg (n = 5, 3.2%), breech delivery (n = 6, 3.9%), fetal distress (n = 8, 5.2%), maternal diabetes (n = 2, 1.3%), clavicular fracture (n = 2, 1.3%), and forceps delivery (n = 4, 2.6%). The comparison with the recent literature suggested that most perinatal OBPP risk factors were within the normal range, although the incidence of shoulder dystocia, forceps and vaginal breech deliveries exceeded the average rates. Conclusion: Perinatal factors related to OBPP did not occur in a higher frequency in patients with Walch type B OA compared to the general population, although some of them were in the high normal range.</jats:p>
Scopus© Citations 3 20
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Increase in Beta Power Reflects Attentional Top-Down Modulation After Psychosocial Stress Induction
(2021)
Ismael Palacios-García
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SILVA CONCHA, JAIME
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Mario Villena-González
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Germán Campos-Arteaga
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Claudio Artigas-Vergara
<jats:p>Selective attention depends on goal-directed and stimulus-driven modulatory factors, each relayed by different brain rhythms. Under certain circumstances, stress-related states can change the balance between goal-directed and stimulus-driven factors. However, the neuronal mechanisms underlying these changes remain unclear. In this study, we explored how psychosocial stress can modulate brain rhythms during an attentional task and a task-free period. We recorded the EEG and ECG activity of 42 healthy participants subjected to either the Trier Social Stress Test (TSST), a controlled procedure to induce stress, or a comparable control protocol (same physical and cognitive effort but without the stress component), flanked by an attentional task, a 90 s of task-free period and a state of anxiety questionnaire. We observed that psychosocial stress induced an increase in heart rate (HR), self-reported anxiety, and alpha power synchronization. Also, psychosocial stress evoked a relative beta power increase during correct trials of the attentional task, which correlates positively with anxiety and heart rate increase, and inversely with attentional accuracy. These results suggest that psychosocial stress affects performance by redirecting attentional resources toward internal threat-related thoughts. An increment of endogenous top-down modulation reflected an increased beta-band activity that may serve as a compensatory mechanism to redirect attentional resources toward the ongoing task. The data obtained here may contribute to designing new ways of clinical management of the human stress response in the future and could help to minimize the damaging effects of persistent stressful experiences.</jats:p>
13 1Scopus© Citations 48
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Major Histocompatibility Complex Class I-Related Chain A (MICA) Allelic Variants Associate With Susceptibility and Prognosis of Gastric Cancer
(2021)
Karen Toledo-Stuardo
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Carolina H. Ribeiro
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Andrea Canals
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Marcela Morales
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Valentina Gárate
<jats:p>Gastric cancer (GC) is the fifth most prevalent type of cancer worldwide. Gastric tumor cells express MICA protein, a ligand to NKG2D receptor that triggers natural killer (NK) cells effector functions for early tumor elimination. <jats:italic>MICA</jats:italic> gene is highly polymorphic, thus originating alleles that encode protein variants with a controversial role in cancer. The main goal of this work was to study <jats:italic>MICA</jats:italic> gene polymorphisms and their relationship with the susceptibility and prognosis of GC. Fifty patients with GC and 50 healthy volunteers were included in this study. MICA alleles were identified using Sanger sequencing methods. The analysis of <jats:italic>MICA</jats:italic> gene sequence revealed 13 MICA sequences and 5 MICA-short tandem repeats (STR) alleles in the studied cohorts We identified MICA<jats:sup>*</jats:sup>002 (<jats:sup>*</jats:sup>A9) as the most frequent allele in both, patients and controls, followed by MICA<jats:sup>*</jats:sup>008 allele (<jats:sup>*</jats:sup>A5.1). MICA<jats:sup>*</jats:sup>009/049 allele was significantly associated with increased risk of GC (OR: 5.11 [95% CI: 1.39–18.74], <jats:italic>p</jats:italic> = 0.014). The analysis of MICA-STR alleles revealed a higher frequency of MICA<jats:sup>*</jats:sup>A5 in healthy individuals than GC patients (OR = 0.34 [95% CI: 0.12–0.98], <jats:italic>p</jats:italic> = 0.046). Survival analysis after gastrectomy showed that patients with MICA<jats:sup>*</jats:sup>002/002 or MICA<jats:sup>*</jats:sup>002/004 alleles had significantly higher survival rates than those patients bearing MICA<jats:sup>*</jats:sup>002/008 (<jats:italic>p</jats:italic> = 0.014) or MICA<jats:sup>*</jats:sup>002/009 (MICA<jats:sup>*</jats:sup>002/049) alleles (<jats:italic>p</jats:italic> = 0.040). The presence of threonine in the position MICA-181 (MICA<jats:sup>*</jats:sup>009/049 allele) was more frequent in GC patients than controls (<jats:italic>p</jats:italic> = 0.023). Molecular analysis of MICA-181 showed that the presence of threonine provides greater mobility to the protein than arginine in the same position (MICA<jats:sup>*</jats:sup>004), which could explain, at least in part, some immune evasion mechanisms developed by the tumor. In conclusion, our findings suggest that the study of MICA alleles is crucial to search for new therapeutic approaches and may be useful for the evaluation of risk and prognosis of GC and personalized therapy.</jats:p>
Scopus© Citations 12 1

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