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1.
Sci Total Environ ; 927: 171982, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38575013

RESUMO

In this research, we developed a biochar-based fertilizer using biogas slurry and biochar derived from lignocellulosic agro-residues. Biogas slurry was obtained through the anaerobic digestion of the organic fraction of municipal solid waste (fresh vegetable biomass and/or prepared food), while biochars were derived from residues from quinoa, maize, rice, and sugarcane. The biochar-based fertilizers were prepared using an impregnation process, where the biogas slurry was mixed with each of the raw biochars. Subsequently, we characterized the N, P and K concentrations of the obtained biochar-based fertilizers. Additionally, we analyzed their surface properties using SEM/EDS and FTIR and conducted a slow-release test on these biochar-based fertilizers to assess their capability to gradually release nutrients. Lastly, a bioassay using cucumber plants was conducted to determine the N, P, and K bioavailability. Our findings revealed a significant correlation (r > 0.67) between the atomic O/C ratio, H/C ratio, cation exchange capacity, surface area, and the base cations concentration with N, P, and/or K adsorption on biochar. These properties, in turn, were linked to the capability of the biochar-based fertilizer to release nutrients in a controlled manner. The biochar-based fertilizer derived from corn residues showed <15 % release of N, P and K at 24 h. Utilization of these biochar-based fertilizers had a positive impact on the mineral nutrition of cucumber plants, resulting in an average increase of 61 % in N, 32 % in P, and 19 % in K concentrations. Our results underscore the potential of biochar-based fertilizers in controlled nutrient release and enhanced plant nutrition. Integration of biochar and biogas slurry offers a promising and sustainable approach for NPK recovery and fertilizer production in agriculture. This study presents an innovative and sustainable approach combining the use of biochar for NPK recovery from biogas slurry and its use as a biochar-based fertilizer in agriculture.


Assuntos
Carvão Vegetal , Fertilizantes , Fertilizantes/análise , Carvão Vegetal/química , Anaerobiose , Agricultura/métodos , Nitrogênio/análise , Potássio/análise , Fósforo/análise , Biocombustíveis
2.
Medicina (Kaunas) ; 59(10)2023 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-37893481

RESUMO

Background and Objectives: In Peru, the presence of antimicrobial-resistant bacteria is a constant concern in hospitals and has likely increased in frequency during the pandemic. The objective of the study was to analyze the frequency of carbapenemase-producing bacteria resistant to two carbapenems (Imipenem and Meropenem), which were isolated from Peruvian patients in the intensive care unit of the Victor Lazarte Echegaray Hospital in Trujillo (Peru) during the COVID-19 pandemic. Materials and Methods: The biological samples of the patients hospitalized in the ICU were processed in the Microbiology Diagnostic Laboratory of the Víctor Lazarte Echegaray Hospital between May 2021 and March 2022. Antimicrobial sensitivity was determined with the automated system AutoScan-4, and for the identification of the type of carbapenemase, the RESISIT-3 O.K.N K-SET cassettes were used. Results: The results show that 76 cultures (76/129) had resistance to the two carbapenems (imipenem or meropenem), where the most frequent were Klebsiella pneuomoniae (31.6%), Pseudomonas aeruginosa (26.3%), and Acinetobacter baumannii (14.5%). Pseudomonas aeruginosa cultures showed at least three carbapenemase types (KPC, NDM, and OXA-48), while A. baumannii, Escherichia coli, and Burkholderia cepacia complex presented at least two carbapenemases (NDM and OXA-48). The carbapenemase NDM was detected in Enterobacter cloacae, Morganella morganii, and Proteus mirabilis, while KPC was present in all Klebsiella pneumoniae and Klebsiella oxytoca cultures. Conclusions: The samples from patients hospitalized in the Victor Lazarte Echegaray Hospital ICU showed a high prevalence of imipenem- and meropenem-resistant bacteria. These findings are relevant and concerning from the perspective of antibiotic-resistant bacteria monitoring, control, and disinfection. Thus, an appropriate antibiotic policy must be implemented.


Assuntos
COVID-19 , Pandemias , Humanos , Meropeném/uso terapêutico , Peru/epidemiologia , beta-Lactamases , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Carbapenêmicos/farmacologia , Carbapenêmicos/uso terapêutico , Imipenem/farmacologia , Imipenem/uso terapêutico , Klebsiella pneumoniae , Escherichia coli , Hospitais , Unidades de Terapia Intensiva , Governo
3.
Am J Reprod Immunol ; 87(1): e13509, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34738282

RESUMO

Antiphospholipid syndrome (APS) is an autoimmune disease characterized by venous, arterial, or small-vessel thrombosis and/or pregnancy-related morbidity, associated with persistent positivity of antiphospholipid antibodies (aPL). Pregnancy-related morbidity in APS patients is characterized by unexplained fetal deaths, premature birth of morphologically normal newborns, and/or consecutive pregnancy losses before the 10th week of gestation. Beta 2-glycoprotein 1 (ß2GP1) is the main antigen recognized by aPL and plays an essential role in the pathogenesis of APS. Antibodies against ß2GP1 (aß2GP1) are involved in damage-generating mechanisms in APS due to their interaction with trophoblasts, decidua, and endothelial cells. aß2GP1 might be used as a prognostic tool for obstetric risk stratification and ß2GP1 could be a target for molecular-targeted treatment to prevent pregnancy morbidity in APS. This review describes these aspects of aß2GP1, including effects on different cellular targets, its association with the severity of obstetric manifestations and the potential of ß2GP1-targeted therapies for APS.


Assuntos
Síndrome Antifosfolipídica/imunologia , Autoanticorpos/imunologia , Complicações na Gravidez/imunologia , beta 2-Glicoproteína I/imunologia , Feminino , Humanos , Gravidez
4.
Front Physiol ; 12: 764702, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34925061

RESUMO

Antiphospholipid syndrome (APS) is an autoimmune disorder characterized by pregnancy morbidity or thrombosis and persistent antiphospholipid antibodies (aPL) that bind to the endothelium and induce endothelial activation, which is evidenced by the expression of adhesion molecules and the production of reactive oxygen species (ROS) and subsequent endothelial dysfunction marked by a decrease in the synthesis and release of nitric oxide (NO). These endothelial alterations are the key components for the development of severe pathological processes in APS. Patients with APS can be grouped according to the presence of other autoimmune diseases (secondary APS), thrombosis alone (thrombotic APS), pregnancy morbidity (obstetric APS), and refractoriness to conventional treatment regimens (refractory APS). Typically, patients with severe and refractory obstetric APS exhibit thrombosis and are classified as those having primary or secondary APS. The elucidation of the mechanisms underlying these alterations according to the different groups of patients with APS could help establish new therapies, particularly necessary for severe and refractory cases. Therefore, this study aimed to evaluate the differences in endothelial activation and dysfunction induced by aPL between patients with refractory obstetric APS and other APS clinical manifestations. Human umbilical vein endothelial cells (HUVECs) were stimulated with polyclonal immunoglobulin-G (IgG) from different groups of patients n = 21), including those with primary (VTI) and secondary thrombotic APS (VTII) and refractory primary (RI+), refractory secondary (RII+), and non-refractory primary (NR+) obstetric APS. All of them with thrombosis. The expression of adhesion molecules; the production of ROS, NO, vascular endothelial growth factor (VEGF), and endothelin-1; and the generation of microparticles were used to evaluate endothelial activation and dysfunction. VTI IgG induced the expression of adhesion molecules and the generation of microparticles and VEGF. RI+ IgG induced the expression of adhesion molecules and decreased NO production. RII+ IgG increased the production of microparticles, ROS, and endothelin-1 and reduced NO release. NR+ IgG increased the production of microparticles and endothelin-1 and decreased the production of VEGF and NO. These findings reveal differences in endothelial activation and dysfunction among groups of patients with APS, which should be considered in future studies to evaluate new therapies, especially in refractory cases.

5.
Biomedica ; 39(4): 673-688, 2019 12 01.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-31860179

RESUMO

Introduction: The antiphospholipid syndrome is characterized by the persistent presence of antiphospholipid antibodies and clinical manifestations of thrombosis or gestational morbidity that are associated with oxidative stress and endothelial dysfunction. Objective: To evaluate markers of oxidative stress in endothelial cells induced by the serum from women with different clinical manifestations of the antiphospholipid syndrome, and to analyze the antioxidant capacity of the sera. Materials and methods: We included 48 women who were classified as follows: presence of antiphospholipid antibodies and clinical criteria of gestational morbidity alone, vascular thrombosis only, and gestational morbidity/vascular thrombosis. Control groups included antiphospholipid antibodies negative women. In an in vitro model of endothelial cells stimulated with sera from women included in the groups, some markers of oxidative stress were determined by flow cytometry. The antioxidant capacity in the sera of these women was analyzed. Results: The sera from the groups of women with antiphospholipid syndrome that presented thrombosis, with or without gestational morbidity, generated a significant increase (p<0.05 and p<0.001) in endothelial oxidative stress markers in contrast to the control of normal human serum. There were no differences in the effect of the sera from the different study groups on endothelial lipid peroxidation. Also, there was also no difference in the antioxidant activity of the sera. Conclusion: Mitochondrial oxidative stress in the endothelium is associated with the presence of thrombosis; instead, its association with gestational morbidity generates intracellular oxidative stress.


Introducción. El síndrome antifosfolípido se caracteriza por la presencia persistente de anticuerpos antifosfolípidos y manifestaciones clínicas de trombosis o morbilidad gestacional, las cuales se asocian con estrés oxidativo y disfunción endotelial. Objetivo. Evaluar los marcadores de estrés oxidativo en células endoteliales, inducidos por el suero de mujeres con diferentes manifestaciones clínicas del síndrome antifosfolípido y analizar la capacidad antioxidante de los sueros. Materiales y métodos. Se incluyeron 48 mujeres que fueron clasificadas así: presencia de anticuerpos antifosfolípidos y criterios clínicos de morbilidad gestacional, trombosis vascular o ambas. Como grupos control se incluyeron mujeres negativas para anticuerpos antifosfolípidos. En un modelo in vitro de células endoteliales estimuladas con los sueros de las mujeres del estudio, se determinaron algunos marcadores de estrés oxidativo por citometría de flujo. También, se analizó la capacidad antioxidante de los sueros incluidos. Resultados. Los sueros de los grupos de mujeres con síndrome antifosfolípido que presentaban trombosis, con morbilidad gestacional o sin ella, generaron un incremento significativo (p<0,05 y p<0,001) en los marcadores de estrés oxidativo endotelial, en contraste con el control de suero humano normal. No se observaron diferencias en el efecto de los sueros de los diferentes grupos de estudio sobre la lipoperoxidación endotelial. Tampoco se encontró diferencia en la actividad antioxidante de los sueros. Conclusión. El estrés oxidativo mitocondrial en el endotelio se asocia con la presencia de trombosis. Sin embargo, cuando esta se asocia con morbilidad gestacional, también se genera estrés oxidativo intracelular.


Assuntos
Anticorpos Antifosfolipídeos/imunologia , Síndrome Antifosfolipídica/imunologia , Células Endoteliais/metabolismo , Estresse Oxidativo/imunologia , Soro/imunologia , Adulto , Síndrome Antifosfolipídica/complicações , Biomarcadores/metabolismo , Estudos de Casos e Controles , Sobrevivência Celular , Feminino , Humanos , Peroxidação de Lipídeos , Gravidez , Complicações na Gravidez/imunologia , Espécies Reativas de Oxigênio/metabolismo , Soro/metabolismo , Superóxidos/metabolismo , Trombose/etiologia , Trombose/imunologia , Veias Umbilicais/citologia
6.
Biomédica (Bogotá) ; 39(4): 673-688, oct.-dic. 2019. tab, graf
Artigo em Espanhol | LILACS | ID: biblio-1089085

RESUMO

Introducción. El síndrome antifosfolípido se caracteriza por la presencia persistente de anticuerpos antifosfolípidos y manifestaciones clínicas de trombosis o morbilidad gestacional, las cuales se asocian con estrés oxidativo y disfunción endotelial. Objetivo. Evaluar los marcadores de estrés oxidativo en células endoteliales, inducidos por el suero de mujeres con diferentes manifestaciones clínicas del síndrome antifosfolípido y analizar la capacidad antioxidante de los sueros. Materiales y métodos. Se incluyeron 48 mujeres que fueron clasificadas así: presencia de anticuerpos antifosfolípidos y criterios clínicos de morbilidad gestacional, trombosis vascular o ambas. Como grupos control se incluyeron mujeres negativas para anticuerpos antifosfolípidos. En un modelo in vitro de células endoteliales estimuladas con los sueros de las mujeres del estudio, se determinaron algunos marcadores de estrés oxidativo por citometría de flujo. También, se analizó la capacidad antioxidante de los sueros incluidos. Resultados. Los sueros de los grupos de mujeres con síndrome antifosfolípido que presentaban trombosis, con morbilidad gestacional o sin ella, generaron un incremento significativo (p<0,05 y p<0,001)en los marcadores de estrés oxidativo endotelial, en contraste con el control de suero humano normal. No se observaron diferencias en el efecto de los sueros de los diferentes grupos de estudio sobre la lipoperoxidación endotelial. Tampoco se encontró diferencia en la actividad antioxidante de los sueros. Conclusión. El estrés oxidativo mitocondrial en el endotelio se asocia con la presencia de trombosis. Sin embargo, cuando esta se asocia con morbilidad gestacional, también se genera estrés oxidativo intracelular.


Introduction: The antiphospholipid syndrome is characterized by the persistent presence of antiphospholipid antibodies and clinical manifestations of thrombosis or gestational morbidity that are associated with oxidative stress and endothelial dysfunction. Objective: To evaluate markers of oxidative stress in endothelial cells induced by the serum from women with different clinical manifestations of the antiphospholipid syndrome, and to analyze the antioxidant capacity of the sera. Materials and methods: We included 48 women who were classified as follows: presence of antiphospholipid antibodies and clinical criteria of gestational morbidity alone, vascular thrombosis only, and gestational morbidity/vascular thrombosis. Control groups included antiphospholipid antibodies negative women. In an in vitro model of endothelial cells stimulated with sera from women included in the groups, some markers of oxidative stress were determined by flow cytometry. The antioxidant capacity in the sera of these women was analyzed. Results: The sera from the groups of women with antiphospholipid syndrome that presented thrombosis, with or without gestational morbidity, generated a significant increase (p<0.05 and p<0.001) in endothelial oxidative stress markers in contrast to the control of normal human serum. There were no differences in the effect of the sera from the different study groups on endothelial lipid peroxidation. Also, there was also no difference in the antioxidant activity of the sera. Conclusion: Mitochondrial oxidative stress in the endothelium is associated with the presence of thrombosis; instead, its association with gestational morbidity generates intracellular oxidative stress.


Assuntos
Síndrome Antifosfolipídica , Estresse Oxidativo , Trombose , Gravidez , Morbidade , Antioxidantes
7.
Front Physiol ; 9: 1840, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30627104

RESUMO

The endothelium is a monolayer of cells that covers the inner surface of blood vessels and its integrity is essential for the maintenance of vascular health. Endothelial dysfunction is a key pathological component of antiphospholipid syndrome (APS). Its systemic complications include thrombotic endocarditis, valvular dysfunction, cerebrovascular occlusions, proliferative nephritis, deep vein thrombosis, and pulmonary embolism. In women, APS is also associated with pregnancy complications (obstetric APS). The conventional treatment regimens for APS are ineffective when the clinical symptoms are severe. Therefore, a better understanding of alterations in the endothelium caused by antiphospholipid antibodies (aPL) may lead to more effective therapies in patients with elevated aPL titers and severe clinical symptoms. Currently, while in vivo analyses of endothelial dysfunction in patients with APS have been reported, most research has been performed using in vitro models with endothelial cells exposed to either patient serum/plasma, monoclonal aPL, or IgGs isolated from patients with APS. These studies have described a reduction in endothelial cell nitric oxide synthesis, the induction of inflammatory and procoagulant phenotypes, an increase in endothelial proliferation, and impairments in vascular remodeling and angiogenesis. Despite these lines of evidence, further research is required to better understand the pathophysiology of endothelial dysfunction in patients with APS. In this review, we have compared the current understanding about the mechanisms of endothelial dysfunction induced by patient-derived aPL under the two main clinical manifestations of APS: thrombosis and gestational complications, either alone or in combination. We also discuss gaps in our current knowledge regarding aPL-induced endothelial dysfunction.

8.
Medicina (Bogotá) ; 40(1(120)): 101-102, Ene-Mar, 2018.
Artigo em Espanhol | LILACS | ID: biblio-910058

RESUMO

Introducción:El síndrome antifosfolipídico (SAF) es una enfermedad autoinmune caracterizada por la presencia persistente de anticuerpos antifosfolípidos (aAFL) y manifestaciones clínicas de trombosis y/o morbilidad gestacional que se asocian con estrés nitrosativo/ oxidativo y disminución de la capacidad antioxidante, alterando el desarrollo gestacional. Objetivo: Evaluar algunos biomarcadores de estrés nitrosativo/oxidativo del suero de mujeres con diferentes manifestaciones clínicas del SAF y sus efectos en células endoteliales. Métodos: Se incluyeron sueros de 48 mujeres divididas en dos grupos con y sin aAFL. Se evaluó la concentración de nitritos, la capacidad antioxidante y la actividad de la enzima paraoxonasa


Assuntos
Síndrome Antifosfolipídica , Estresse Nitrosativo , Estresse Oxidativo
9.
Medicina (Bogotá) ; 40(1(120)): 110-110, Ene-Mar, 2018.
Artigo em Espanhol | LILACS | ID: biblio-910064

RESUMO

Introducción y Objetivo: Los anticuerpos antifosfolípidos (aAFL) se pueden unir a las células trofoblásticas o a las endoteliales, alterando la remodelación vascular y consecuentemente la placentación normal. El objetivo fue evaluar el efecto del suero de pacientes con síndrome antifosfolipídico (SAF) obstétrico en la interacción endotelio-trofoblasto utilizando un modelo in vitro tridimensional de remodelación vascular. Métodos: Las pacientes con aAFL fueron clasificadas en dos grupos: morbilidad gestacional y trombosis (MG/TV, n=7) y morbilidad gestacional sola (MG, n=8). Como control, se incluyeron mujeres sin aAFL con MG (MG/ aAFL-, n=10), y mujeres sanas (SHN, n=7). Células endoteliales HUVEC fueron cultivadas en Matrigel™ hasta formar estructuras tubulares (angiogénesis) y luego se adicionaron células trofoblásticas HTR8; estas células invaden las estructuras tubulares de las células endoteliales mejorando su estabilidad. Se evaluó el efecto de 10% del suero de las mujeres del estudio sobre esta interacción.


Assuntos
Síndrome Antifosfolipídica , Lipoxinas , Remodelação Vascular
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