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1.
J Clin Med ; 13(10)2024 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-38792314

RESUMEN

Spinal cord injury is a complicated medical condition both from the clinician's point of view in terms of management and from the patient's perspective in terms of unsatisfactory recovery. Depending on the severity, this disorder can be devastating despite the rapid and appropriate use of modern imaging techniques and convenient surgical spinal cord decompression and stabilization. In this context, there is a mandatory need for novel adjunctive therapeutic approaches to classical treatments to improve rehabilitation chances and clinical outcomes. This review offers a new and original perspective on therapies targeting the microglia, one of the most relevant immune cells implicated in spinal cord disorders. The first part of the manuscript reviews the anatomical and pathophysiological importance of the blood-spinal cord barrier components, including the role of microglia in post-acute neuroinflammation. Subsequently, the authors present the emerging therapies based on microglia modulation, such as cytokines modulators, stem cell, microRNA, and nanoparticle-based treatments that could positively impact spinal cord injury management. Finally, future perspectives and challenges are also highlighted based on the ongoing clinical trials related to medications targeting microglia.

2.
Int J Mol Sci ; 25(10)2024 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-38791590

RESUMEN

This paper describes the process of producing chemiresistors based on hybrid nanostructures obtained from graphene and conducting polymers. The technology of graphene presumed the following: dispersion and support stabilization based on the chemical vapor deposition technique; transfer of the graphene to the substrate by spin-coating of polymethyl methacrylate; and thermal treatment and electrochemical delamination. For the process at T = 950 °C, a better settlement of the grains was noticed, with the formation of layers predominantly characterized by peaks and not by depressions. The technology for obtaining hybrid nanostructures from graphene and conducting polymers was drop-casting, with solutions of Poly(3-hexylthiophene (P3HT) and Poly[(9,9-dioctylfluorenyl-2,7-diyl)-co-bithiophene] (F8T2). In the case of F8T2, compared to P3HT, a 10 times larger dimension of grain size and about 7 times larger distances between the peak clusters were noticed. To generate chemiresistors from graphene-polymer structures, an ink-jet printer was used, and the metallization was made with commercial copper ink for printed electronics, leading to a structure of a resistor with an active surface of about 1 cm2. Experimental calibration curves were plotted for both sensing structures, for a domain of CH4 of up to 1000 ppm concentration in air. A linearity of the curve for the low concentration of CH4 was noticed for the graphene structure with F8T2, presenting a sensitivity of about 6 times higher compared with the graphene structure with P3HT, which makes the sensing structure of graphene with F8T2 more feasible and reliable for the medical application of irritable bowel syndrome evaluation.


Asunto(s)
Grafito , Síndrome del Colon Irritable , Metano , Nanoestructuras , Polímeros , Grafito/química , Nanoestructuras/química , Polímeros/química , Metano/química , Síndrome del Colon Irritable/metabolismo , Humanos , Pruebas Respiratorias/métodos , Tiofenos/química , Conductividad Eléctrica
3.
Polymers (Basel) ; 16(8)2024 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-38675050

RESUMEN

This paper presents the obtaining and characterization of recycled polypropylene/strontium ferrite (PP/SrFe12O19) polymer composite materials with applications in the electromagnetic shielding of vehicle interiors (mainly automotive electronics-carcasses) from the electromagnetic radiation emitted mainly by exterior sources-electrical lines and supply sources-in terms of the development of the new electrical vehicles. With this aim, suitable polymer composite materials were developed using SrFe12O19 filler in two forms (powder and concentrate). The recycled PP polymer and composite materials with a PP/SrFe12O19 weight ratio of 75/25 and 70/30 were obtained in two stages, i.e., pellets by extrusion and samples for testing through a melt injection process. The characterization of the obtained materials took into account the requirements imposed by the desired applications. It consisted of determining the mechanical and dielectric properties, and microstructure analyses, along with the determination of the resistance to the action of a temperature of 70 °C, which is higher than the temperatures created during the summer inside vehicles. The performance of these materials as electromagnetic shields was assessed through functional tests consisting of the determination of magnetic permeability and the estimation of the electromagnetic shielding efficiency (SE). The obtained results confirmed the improvement of the mechanical, dielectric, and magnetic properties of the PP/SrFe12O19 composites compared to the selected PP polymers. It is also found that all the composite materials exhibited reflective shielding properties (SER from -71.5 dB to -56.7 dB), with very little absorption shielding. The most performant material was the composite made of PP/SrFe12O19 powder with a weight ratio of 70/30. The promising results recommend this composite material for potential use in automotive shielding applications against electromagnetic pollution.

4.
Front Aging ; 4: 1234958, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37602277

RESUMEN

Neurodegenerative disorders, particularly Alzheimer's disease (AD), remain a great challenge regarding the finding of effective treatment, one main reason being the incomplete understanding of their etiology. With many intensely debated hypotheses, a newer approach based on the impact of iron imbalance in sustaining neurodegeneration in the central nervous system becomes increasingly popular. Altered iron homeostasis leads to increased iron accumulation in specific brain areas, explaining the clinical picture of AD patients. Moreover, growing evidence sustains the significant impact of iron metabolism in relationship to other pathological processes encountered in the AD-affected brain, such as the amyloidogenic pathway, chronic inflammation, or oxidative stress. In this context, this mini-review aims to summarize the novel data from the continuously expanding literature on this topic in a didactic manner. Thus, in the first part, the authors briefly highlight the most relevant aspects related to iron absorption, transport, regulation, and elimination at the cerebral level, focusing on the role of the blood-brain barrier and the newer concept of ferroptosis. Subsequently, currently available iron chelation therapies are discussed, including an overview of the most relevant clinical trials on this topic. In the final part, based on the latest results from in vitro and in vivo studies, new research directions are suggested to enhance the development of effective antidementia therapies.

5.
Biomedicines ; 11(5)2023 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-37239082

RESUMEN

Amyloid beta peptide is an important biomarker in Alzheimer's disease, with the amyloidogenic hypothesis as one of the central hypotheses trying to explain this type of dementia. Despite numerous studies, the etiology of Alzheimer's disease remains incompletely known, as the pathological accumulation of amyloid beta aggregates cannot fully explain the complex clinical picture of the disease. Or, for the development of effective therapies, it is mandatory to understand the roles of amyloid beta at the brain level, from its initial monomeric stage prior to aggregation in the form of senile plaques. In this sense, this review aims to bring new, clinically relevant data on a subject intensely debated in the literature in the last years. In the first part, the amyloidogenic cascade is reviewed and the possible subtypes of amyloid beta are differentiated. In the second part, the roles played by the amyloid beta monomers in physiological and pathological (neurodegenerative) conditions are illustrated based on the most relevant and recent studies published on this topic. Finally, considering the importance of amyloid beta monomers in the pathophysiology of Alzheimer's disease, new research directions with diagnostic and therapeutic impacts are suggested.

6.
Medicina (Kaunas) ; 59(5)2023 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-37241098

RESUMEN

Both the Chronic Liver Failure Consortium (CLIF-C) organ failure score (OFs) and the CLIF-C acute-on-chronic-liver failure (ACLF) score (ACLFs) were developed for risk stratification and to predict mortality in patients with liver cirrhosis and ACLF. However, studies validating the predictive ability of both scores in patients with liver cirrhosis and concomitant need for intensive care unit (ICU) treatment are scarce. The aim of the present study is to validate the predictive ability of the CLIF-C OFs and CLIF-C ACLFs regarding the rationale of ongoing ICU treatment and to investigate their predictive ability regarding 28-days (short-), 90-days (medium-), and 365-days (long-term) mortality in patients with liver cirrhosis treated in an ICU. Patients with liver cirrhosis and acute decompensation (AD) or ACLF and concomitant need for ICU treatment were retrospectively analyzed. Predictive factors for mortality, defined as transplant-free survival, were identified using multivariable regression analyses and the predictive ability of CLIF-C OFs, CLIF-C ACLFs, MELD score, and AD score (ADs) was assessed by determining the AUROC. Of 136 included patients, 19 patients presented with AD and 117 patients with ACLF at ICU admission. In multivariable regression analyses, CLIF-C OFs as well as CLIF-C ACLFs were independently associated with higher short-, medium-, and long-term mortality after adjusting for confounding variables. The predictive ability of the CLIF-C OFs in the total cohort in short-term was 0.687 (95% CI 0.599-0.774). In the subgroup of patients with ACLF, the respective AUROCs were 0.652 (95% CI 0.554-0.750) and 0.717 (95% CI 0.626-0.809) for the CLIF-C OFs and for the CLIF-C ACLFs, respectively. ADs performed well in the subgroup of patients without ACLF at ICU admission with an AUROC of 0.792 (95% CI 0.560-1.000). In the long-term, the AUROCs were 0.689 (95% Cl 0.581-0.796) and 0.675 (95% Cl 0.550-0.800) for CLIF-C OFs and CLIF-C ACLFs, respectively. The predictive ability of CLIF-C OFs and CLIF-C ACLFs was relatively low to predict short- and long-term mortality in patients with ACLF with concomitant need for ICU treatment. However, the CLIF-C ACLFs may have special merit in judging futility of further ICU treatment.


Asunto(s)
Insuficiencia Hepática Crónica Agudizada , Cirrosis Hepática , Humanos , Estudios Retrospectivos , Pronóstico , Cirrosis Hepática/complicaciones , Puntuaciones en la Disfunción de Órganos , Insuficiencia Hepática Crónica Agudizada/complicaciones , Unidades de Cuidados Intensivos
7.
J Cachexia Sarcopenia Muscle ; 13(1): 169-179, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34881516

RESUMEN

BACKGROUND: Assessment of muscle quantity by sonographic muscle indices could help identify patients at risk for fatal outcome during coronavirus disease-2019 (COVID-19). The aim of this study was to explore sonographic muscle indices as predictors of COVID-19 outcome and to test the feasibility of sonographic muscle measurement in an isolation context. METHODS: Muscle indices, derived from the psoas muscle or thigh muscles, were quantified by sonography in a cohort of patients without COVID-19 to obtain reference values for low muscle quantity. Gender-specific median of different muscle indices were defined as threshold value for low muscle quantity. The prognostic relevance of low muscle quantity, was prospectively explored in two cohorts of hospitalized COVID-19 patients. Optimal muscle index cutoff values predictive for 30 day mortality during COVID-19 were determined by receiver operating characteristic-area under the curve and Youden index calculation. Muscle quantity and known prognostic factors of COVID-19 were analysed by multivariable log-regression. RESULTS: Compared with other muscle indices, the psoas muscle area index (PMAI) showed the most favourable characteristics to predict outcome of COVID-19 disease. Sonographic morphometry of patients without COVID-19 (n = 136) revealed a gender-specific median for PMAI (male: 291.1 mm2 /m2 , female 260.6 mm2 /m2 ) as threshold value of low muscle quantity. Subsequently, COVID-19 patients (Cohort I: n = 58; Cohort II: n = 55) were prospectively assessed by bedside sonography. The studied COVID-19 patients developed a critical course of disease in 22.4% (Cohort I: n = 13/58) and 34.5% (Cohort II: n = 20/55). Mortality rate reached 12.1% (Cohort I: n = 7/58) and 20.0% (Cohort I: n = 11/55) within 30 days of follow up. COVID-19 patients with a PMAI below the gender-specific median showed a higher 30 day mortality in both COVID-19 cohorts (log rank, P < 0.05). The optimal PMAI cutoff value (206 mm2 /m2 ) predicted 30 day mortality of hospitalized COVID-19 patients with a sensitivity of 72% and specificity of 78.5% (receiver operating characteristic-area under the curve: 0.793, 95% confidence interval 0.671-0.914, P = 0.008). Multivariable log-regression analysis of PMAI, age, gender, BMI and comorbidities confirmed an independent association of low PMAI with 30 day mortality of COVID-19 patients (P = 0.018). CONCLUSIONS: Sonographic morphometry provides reliable muscle quantification under hygienic precautions and allows risk stratification of patients with COVID-19.


Asunto(s)
COVID-19 , Femenino , Humanos , Masculino , Estudios Prospectivos , Músculos Psoas/diagnóstico por imagen , Estudios Retrospectivos , SARS-CoV-2
8.
J Thromb Haemost ; 19(9): 2335-2347, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34242469

RESUMEN

BACKGROUND: Coronavirus disease 19 (COVID-19)-associated coagulopathy is a hallmark of disease severity and poor prognosis. The key manifestations of this prothrombotic syndrome-microvascular thrombosis, stroke, and venous and pulmonary clots-are also observed in severe and catastrophic antiphospholipid syndrome. Antiphospholipid antibodies (aPL) are detectable in COVID-19 patients, but their association with the clinical course of COVID-19 remains unproven. OBJECTIVES: To analyze the presence and relevance of lipid-binding aPL in hospitalized COVID-19 patients. METHODS: Two cohorts of 53 and 121 patients from a single center hospitalized for PCR-proven severe acute respiratory syndrome-coronavirus 2 infection were analyzed for the presence of aPL and clinical severity of COVID-19. RESULTS: We here demonstrate that lipid-binding aPL are common in COVID-19. COVID-19 patients with lipid-binding aPL have higher median concentrations of C-reactive protein and D-dimer, and are more likely to have a critical clinical course and fatal outcome. Lipid-binding aPL isolated from COVID-19 patients target the recently described cell surface complex of lysobisphosphatidic acid (LBPA) with the protein C receptor (EPCR) to induce prothrombotic and inflammatory responses in monocytes and endothelial cells. We show that B1a cells producing lipid-reactive aPL of the IgG isotype circulate in the blood of COVID-19 patients. In vivo, COVID-19 aPL accelerate thrombus formation in an experimental mouse model dependent on the recently delineated signaling pathway involving EPCR-LBPA. CONCLUSIONS: COVID-19 patients rapidly expand B1a cells secreting pathogenic lipid-binding aPL with broad thrombotic and inflammatory effects. The association with markers of inflammation and coagulation, clinical severity, and mortality suggests a causal role of aPL in COVID-19-associated coagulopathy.


Asunto(s)
Síndrome Antifosfolípido , COVID-19 , Animales , Anticuerpos Antifosfolípidos , Células Endoteliales , Humanos , Ratones , SARS-CoV-2
9.
Clin Case Rep ; 8(12): 2990-2994, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33363865

RESUMEN

The biological anakinra appears promising to halt cytokine storm syndrome seen in severe courses of COVID-19. However, immunosuppression with anakinra may facilitate sepsis, necessitating continuous screening for bacterial superinfections.

10.
Gastroenterology ; 142(4): 782-789.e3, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22248661

RESUMEN

BACKGROUND & AIMS: Fractionated plasma separation and adsorption (FPSA) is an extracorporeal procedure that supports liver function by removing endogenous toxins that cause complications from acute-on-chronic liver failure (AOCLF). We performed a randomized trial to investigate survival of patients with AOCLF treated with FPSA. METHODS: Patients with AOCLF were randomly assigned to groups given a combination of FPSA and standard medical therapy (SMT) (FPSA group, n = 77) or only SMT (SMT group, n = 68). The Prometheus liver support system was used to provide 8 to 11 rounds of FPSA (minimum of 4 hours each) for 3 weeks. Primary end points were survival probabilities at days 28 and 90, irrespective of liver transplantation. RESULTS: Baseline clinical parameters and number of transplant patients were similar between study arms. Serum bilirubin level decreased significantly in the FPSA group but not in the SMT group. In an intention-to-treat analysis, the probabilities of survival on day 28 were 66% in the FPSA group and 63% in the SMT group (P = .70); on day 90, they were 47% and 38%, respectively (P = .35). Baseline factors independently associated with poor prognosis were high SOFA score, bleeding, female sex, spontaneous bacterial peritonitis, intermediate increases in serum creatinine concentration, and combination of alcoholic and viral etiology of liver disease. There were no differences between the 2 groups in the incidence of side effects. CONCLUSIONS: Among all patients with AOCLF, extracorporeal liver support with FPSA does not increase the probability of survival. Further studies are needed to assess whether therapy might be beneficial in specific subsets of patients.


Asunto(s)
Enfermedad Hepática en Estado Terminal/terapia , Circulación Extracorporea , Fallo Hepático Agudo/terapia , Desintoxicación por Sorción , Adulto , Bilirrubina/sangre , Biomarcadores/sangre , Enfermedad Hepática en Estado Terminal/diagnóstico , Enfermedad Hepática en Estado Terminal/mortalidad , Europa (Continente) , Circulación Extracorporea/efectos adversos , Circulación Extracorporea/mortalidad , Femenino , Humanos , Estimación de Kaplan-Meier , Fallo Hepático Agudo/diagnóstico , Fallo Hepático Agudo/mortalidad , Masculino , Persona de Mediana Edad , Modelos de Riesgos Proporcionales , Estudios Prospectivos , Medición de Riesgo , Factores de Riesgo , Desintoxicación por Sorción/efectos adversos , Desintoxicación por Sorción/mortalidad , Factores de Tiempo , Resultado del Tratamiento
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