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Introduction: Founded in 2019, the "ResISSSTE Cerebro" program is the first and only stroke network within the Mexican public health system. One advanced stroke center (ASC) and seven essential stroke centers (ESC) provide acute stroke (AS) care through a modified hub-and-spoke model. This study describes the workflow, metrics, and outcomes in AS obtained during the program's third year of operation. Materials and methods: Participants were adult beneficiaries of the ISSSTE health system in Mexico City with acute focal neurological deficit within 24 h of symptom onset. Initial evaluation could occur at any facility, but the stroke team at the ASC took all decisions regarding treatment and transfers of patients. Registered variables included demographics, stroke risk factors, AS treatment workflow time points, and clinical outcome measures. Results: We analyzed data from 236 patients, 104 (44.3%) men with a median age of 71 years. Sixty percent of the patients were initially evaluated at the ESC, and 122 (85.9%) were transferred to the ASC. The median transfer time was 123 min. The most common risk factor was hypertension (73.6%). Stroke subtypes were ischemic (86.0%) and hemorrhagic (14.0%). Median times for onset-to-door, door-to-imaging, door-to-needle, and door-to-groin were: 135.5, 37.0, 76.0, and 151.5 min, respectively. The rate of intravenous thrombolysis was 35%. Large vessel occlusion was present in 63 patients, from whom 44% received endovascular therapy; 71.4% achieved early clinical improvement (median NIHSS reduction of 11 points). Treatment-associated morbimortality was 3.4%. Conclusion: With the implementation of a modified hub-and-spoke model, this study shows that delivery of AS care in low- and middle-income countries is feasible and achieves good clinical outcomes.
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Autoimmune lymphoproliferative syndrome (ALPS) is a rare disease defined as a defect in the lymphocyte apoptotic pathway. Currently, the diagnosis of ALPS is based on clinical aspects, defective lymphocyte apoptosis and mutations in Fas, FasL and Casp 10 genes. Despite this, ALPS has been misdiagnosed. The aim of this work was to go one step further in the knowledge of the disease, through a molecular and proteomic analysis of peripheral blood mononuclear cells (PBMCs) from two children, a 13-year-old girl and a 6-year-old boy, called patient 1 and patient 2, respectively, with clinical data supporting the diagnosis of ALPS. Fas, FasL and Casp10 genes from both patients were sequenced, and a sample of the total proteins from patient 1 was analyzed by label-free proteomics. Pathway analysis of deregulated proteins from PBMCs was performed on the STRING and PANTHER bioinformatics databases. A mutation resulting in an in-frame premature stop codon and protein truncation was detected in the Fas gene from patient 2. From patient 1, the proteomic analysis showed differences in the level of expression of proteins involved in, among other processes, cell cycle, regulation of cell cycle arrest and immune response. Noticeably, the most down-regulated protein is an important regulator of the cell cycle process. This could be an explanation of the disease in patient 1.
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Síndrome Linfoproliferativo Autoinmune , Adolescente , Síndrome Linfoproliferativo Autoinmune/diagnóstico , Síndrome Linfoproliferativo Autoinmune/genética , Niño , Femenino , Humanos , Leucocitos Mononucleares , Masculino , Mutación , Proteómica , Receptor fas/genéticaRESUMEN
PURPOSE: To describe the differences in the serum levels of MMP-2 and MMP-9 of patients with vertebrobasilar dolichoectasia (VBD) with and without acute stroke. METHODS: Case-control study. From an outpatient clinic, we recruited 14 controls and 19 patients with VBD. We also recruited 33 patients with stroke from two emergency departments, 14 without VBD (S/-VBD) and 19 with VBD (S/ + VBD). All the patients underwent serum MMP-2 and MMP-9 measurements and a non-contrast CT scan. Two investigators assessed the intracranial vertebral arteries (VA) and the basilar artery (BA) at the mid-pons. Diagnosis of VBD was made if the BA diameter was ≥ 4.5 mm. RESULTS: The mean age of the 66 patients studied was 57.6 + 16.0 years, 41% female. In the 33 patients with stroke, the median NIHSS was 8 (range 15); there were no differences in the NIHSS scores between both groups with stroke. Median MMP-2 levels were lower in the S/-VBD when compared to controls. Median MMP-9 serum levels were higher in both groups with VBD when compared to controls and the S/-VDB group. Both groups with stroke exhibited higher MMP-9 serum levels than controls but were not statistically different from those found in patients with VBD. Serum levels of MMP-9 were significantly correlated with the diameters of the BA (r = 0.344, p = 0.01) and the left VA (r = 0.305, p = 0.05). CONCLUSION: This study found that high serum levels of MMP-9 are associated with VBD independently of stroke and correlated with the degree of VBD.
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Accidente Cerebrovascular , Insuficiencia Vertebrobasilar , Adulto , Anciano , Estudios de Casos y Controles , Femenino , Humanos , Masculino , Metaloproteinasa 2 de la Matriz , Metaloproteinasa 9 de la Matriz , Persona de Mediana Edad , Accidente Cerebrovascular/complicaciones , Accidente Cerebrovascular/diagnóstico por imagen , Insuficiencia Vertebrobasilar/diagnóstico por imagenRESUMEN
In recent years, many studies have focused on heterochromatin located at chromosome ends, which plays an important role in regulating gene expression in many organisms ranging from yeast to humans. Similarly, in the protozoan Plasmodium falciparum, which is the most virulent human malaria parasite, the heterochromatin present in telomeres and subtelomeric regions exerts a silencing effect on the virulence gene families located therein. Studies addressing P. falciparum chromosome ends have demonstrated that these regions participate in other functions, such as the formation of the T-loop structure, the replication of telomeric regions, the regulation of telomere length and the formation of telomeric heterochromatin. In addition, telomeres are involved in anchoring chromosome ends to the nuclear periphery, thereby playing an important role in nuclear architecture and gene expression regulation. Here, we review the current understanding of chromosome ends, the proteins that bind to these regions and their impact on the biology and virulence of P. falciparum.
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Regulación de la Expresión Génica , Heterocromatina/metabolismo , Plasmodium falciparum/fisiología , Plasmodium falciparum/patogenicidad , Telómero/metabolismoRESUMEN
Chromosome ends have been implicated in the default silencing of clonally variant gene families in the human malaria parasite Plasmodium falciparum. These chromosome regions are organized into heterochromatin, as defined by the presence of a repressive histone H3 lysine 9 trimethylated marker and heterochromatin protein 1. Here, we show that the non-coding subtelomeric region adjacent to virulence genes forms facultative heterochromatin in a cell cycle-dependent manner. We demonstrate that telomere-associated repeat elements (TAREs) and telomeres are transcribed as long non-coding RNAs (lncRNAs) during schizogony. Northern blot assays revealed two classes of lncRNAs: a ~4-kb transcript composed of telomere sequences and a TARE-3 element, and a >6-kb transcript composed of 21-bp repeats from TARE-6. These lncRNAs are transcribed by RNA polymerase II as single-stranded molecules. RNA-FISH analysis showed that these lncRNAs form several nuclear foci during the schizont stage, whereas in the ring stage, they are located in a single perinuclear compartment that does not co-localize with any known nuclear subcompartment. Furthermore, the TARE-6 lncRNA is predicted to form a stable and repetitive hairpin structure that is able to bind histones. Consequently, the characterization of the molecular interactions of these lncRNAs with nuclear proteins may reveal novel modes of gene regulation and nuclear function in P. falciparum.
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Núcleo Celular/metabolismo , Plasmodium falciparum/genética , ARN Protozoario/metabolismo , ARN no Traducido/metabolismo , Telómero/metabolismo , Animales , Northern Blotting , Núcleo Celular/genética , Cromosomas/genética , Cromosomas/metabolismo , Clonación Molecular , Regulación de la Expresión Génica , Heterocromatina/genética , Heterocromatina/metabolismo , Histonas/metabolismo , Hibridación Fluorescente in Situ/métodos , Plásmidos/genética , Plásmidos/metabolismo , Plasmodium falciparum/metabolismo , Unión Proteica , Proteínas Protozoarias/genética , Proteínas Protozoarias/metabolismo , ARN Polimerasa II/genética , ARN Polimerasa II/metabolismo , Estabilidad del ARN , ARN Protozoario/genética , ARN no Traducido/genética , Secuencias Repetitivas de Ácidos Nucleicos , Esquizontes/citología , Esquizontes/metabolismo , Telómero/genética , Transcripción GenéticaRESUMEN
Until very recently, little was known about the chromatin structure of the telomeres and subtelomeric regions in Plasmodium falciparum. In yeast and Drosophila melanogaster, chromatin structure has long been known to be an important aspect in the regulation and functioning of these regions. Telomeres and subtelomeric regions are enriched in epigenetic marks that are specific to heterochromatin, such as methylation of lysine 9 of histone H3 and lysine 20 of histone H4. In P. falciparum, histone modifications and the presence of both the heterochromatin "writing" (PfSir2, PKMT) and "reading" (PfHP1) machinery at telomeric and subtelomeric regions indicate that these regions are likely to have heterochromatic structure that is epigenetically regulated. This structure may be important for telomere functions such as the silencing of the var gene family implicated in the cytoadherence and antigenic variation of these parasites.
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Heterocromatina/metabolismo , Plasmodium falciparum/metabolismo , Telómero/metabolismo , Cromosomas/metabolismo , Histonas/metabolismo , Plasmodium falciparum/genética , Procesamiento Proteico-PostraduccionalRESUMEN
Ether à go-go (EAG) potassium channels possess oncogenic properties and have gained great interest as research tools for cancer detection and therapy. Besides, EAG electrophysiological properties are regulated through the cell cycle and determined by cytoskeletal interactions. Thus, because of the pivotal role of extracellular matrix (ECM) and cytoskeleton in cancer progression, we studied the effect of ECM components on adhesion, viability, actin organization and EAG currents in wild-type CHO cells (CHO-wt) and cells expressing human EAG channels (CHO-hEAG). At short incubation times, adhesion and viability of CHO-hEAG cells grown on collagen, heparin or poly-lysine were lower than CHO-wt cells, however, only CHO-hEAG sustained growing under total serum starvation. CHO-hEAG cells grown on poly-lysine did not organize their cytoskeleton but when grown on collagen or fibronectin displayed lamellipodia and stress fibers, respectively. Interestingly, EAG expressing cells displayed special actin structures suggesting a dynamic actin cytoskeleton, such structures were not exhibited by wild-type cells. EAG current density was significantly lower in cells grown on collagen at short incubation times. Finally, we studied potential associations between hEAG channels and integrins or actin filaments by confocal microscopy. No association between beta1-integrins and hEAG channels was found, however, a very strong co-localization was observed between hEAG channels and actin filaments, supported by immunoblot experiments in which hEAG channels were found in the insoluble fraction (associated to cytoskeleton). Our results suggest ECM components as potential modulators of oncogenic human-EAG expressing cells and emphasize the relationship between potassium channels, cytoskeleton, ECM and cancer.