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1.
Spectrochim Acta A Mol Biomol Spectrosc ; 321: 124729, 2024 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-38955073

RESUMEN

There is an urgent requirement for the development of sensitive and quick sensors to monitor chromium (VI) due to its substantial carcinogenic and mutagenic properties. A coexisting system of coumarin 334 and diphenylcarbazide (C334/DPC) was used in this study as a fluorescent chemosensor to detect Cr(VI) ions. Upon the addition of Cr(VI), a purple chelate complex (Cr(III)-diphenylcarbazone) was produced, which resulted from the quantitative reaction between Cr(VI) ions and diphenylcarbazide (DPC), whereas no interaction between Cr(VI) and coumarin 334 took place. More interestingly, the absorption spectra of purple (Cr(III)-diphenylcarbazone) complex (λmax = 540 nm) were overlapped with emission and excitation spectra of coumarin 334 (λex/em = 453/492), resulting in the efficient quenching of coumarin 334 (C334) via the inner filter effect. Furthermore, the semi-quantitative estimation of Cr(VI) ion concentration may be achieved by visually watching the progressive color transformation of the probe from yellow to red after the addition different concentration of Cr(VI). The calibration plot for determination of Cr(VI) by this method is ranging from 0.048 to 268 µM. DFT calculations were conducted to enrich our understanding about the mechanism of action. This approach demonstrates an excellent selectivity and sensitivity for Cr(VI) including a detection limit of 48 nM. The new sensor was successfully applied to water samples (tap, mineral, and waste waters). The accuracy was confirmed by the atomic absorption spectroscopy.

2.
Am J Addict ; 33(4): 393-399, 2024 07.
Artículo en Inglés | MEDLINE | ID: mdl-38351440

RESUMEN

BACKGROUND AND OBJECTIVES: Addiction is a chronic disorder that comes with emotional and financial burdens. Several neurobiological factors were correlated to opiate-use disorder which is brain-derived neurotrophic factor (BDNF). BDNF has been found to be involved in long-term potentiation of synaptic strength, a mechanism that is thought to motivate both natural adaption mechanisms as well as the development of addictive behavior. In this study, we aimed to address the relation between BDNF serum level and heroin craving and the effect of duration of abstinence on them. METHODS: A case study was conducted on 80 subjects from Kasr Al-Ainy Psychiatry and Addiction Treatment Hospital with a history of heroin dependence and were divided into two groups: Group A had 40 active heroin-dependent subjects while in Group B, 40 subjects with 1-year heroin abstinence. Severity of addiction was assessed by the addiction severity index, heroin craving was measured by Brief Substance Craving Scale and serum BDNF level was investigated using an enzyme-linked immunosorbent assay. RESULTS: The findings show that active heroin users had significantly higher serum BDNF which is associated with high heroin craving in comparison to the abstinent group. CONCLUSIONS AND SCIENTIFIC SIGNIFICANCE: This study revealed a significant positive correlation between serum BDNF levels and craving in active heroin users versus 1-year abstinent subjects. It is the first study to address the relationship between craving and serum BDNF level in a 1-year abstinent participants. These findings help to determine the brain alterations associated with illness and recovery in heroin dependence.


Asunto(s)
Factor Neurotrófico Derivado del Encéfalo , Ansia , Dependencia de Heroína , Humanos , Factor Neurotrófico Derivado del Encéfalo/sangre , Dependencia de Heroína/sangre , Dependencia de Heroína/psicología , Ansia/fisiología , Masculino , Adulto , Estudios de Casos y Controles , Femenino , Persona de Mediana Edad , Adulto Joven , Factores de Tiempo
3.
Clin Transl Immunology ; 11(1): e1366, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35003749

RESUMEN

OBJECTIVES: Anti-CD20 monoclonal antibody therapy rapidly depletes > 95% of CD20+ B cells from the circulation. B-cell depletion is an effective treatment for autoimmune disease and B-cell malignancies but also increases the risk of respiratory tract infections. This effect on adaptive immunity could be countered by vaccination. We have used mouse models to investigate the effects of B-cell depletion on pneumococcal vaccination, including protection against infection and timing of vaccination in relation to B-cell depletion. METHODS: C57BL/6 female mice were B-cell depleted using anti-CD20 antibody and immunized with two doses of Prevnar-13 vaccine either before or after anti-CD20 treatment. B-cell repertoire and Streptococcus pneumoniae-specific IgG levels were measured using whole-cell ELISA and flow cytometry antibody-binding assay. Protection induced by vaccination was assessed by challenging the mice using a S. pneumoniae pneumonia model. RESULTS: Antibody responses to S. pneumoniae were largely preserved in mice B-cell depleted after vaccination resulting in full protection against pneumococcal infections. In contrast, mice vaccinated with Prevnar-13 while B cells were depleted (with > 90% reduction in B-cell numbers) had decreased circulating anti-S. pneumoniae IgG and IgM levels (measured using ELISA and flow cytometry antibody binding assays). However, some antibody responses were maintained, and, although vaccine-induced protection against S. pneumoniae infection was impaired, septicaemia was still prevented in 50% of challenged mice. CONCLUSIONS: This study showed that although vaccine efficacy during periods of profound B-cell depletion was impaired some protective efficacy was preserved, suggesting that vaccination remains beneficial.

4.
J Cardiovasc Magn Reson ; 23(1): 44, 2021 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-33794918

RESUMEN

The Society for Cardiovascular Magnetic Resonance (SCMR) is an international society focused on the research, education, and clinical application of cardiovascular magnetic resonance (CMR). The SCMR web site ( https://www.scmr.org ) hosts a case series designed to present case reports demonstrating the unique attributes of CMR in the diagnosis or management of cardiovascular disease. Each clinical presentation is followed by a brief discussion of the disease and unique role of CMR in disease diagnosis or management guidance. By nature, some of these are somewhat esoteric, but all are instructive. In this publication, we provide a digital archive of the 2019 Case of the Week series as a means of further enhancing the education of those interested in CMR and as a means of more readily identifying these cases using a PubMed or similar search engine.


Asunto(s)
Síndrome de Churg-Strauss/diagnóstico por imagen , Imagen por Resonancia Magnética , Trombosis/diagnóstico por imagen , Disfunción Ventricular Izquierda/diagnóstico por imagen , Antineoplásicos/efectos adversos , Cardiotoxicidad , Síndrome de Churg-Strauss/fisiopatología , Síndrome de Churg-Strauss/terapia , Diagnóstico Diferencial , Femenino , Neoplasias Cardíacas/diagnóstico por imagen , Humanos , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Trombosis/fisiopatología , Trombosis/terapia , Disfunción Ventricular Izquierda/inducido químicamente , Disfunción Ventricular Izquierda/fisiopatología , Disfunción Ventricular Izquierda/terapia , Función Ventricular Izquierda/efectos de los fármacos , Adulto Joven
5.
Pediatr Res ; 89(3): 464-475, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-32521540

RESUMEN

BACKGROUND: Exposure to inflammation exacerbates injury in neonatal encephalopathy (NE). We hypothesized that brain biomarker mRNA, cytokine mRNA and microRNA differentiate inflammation (E. coli LPS), hypoxia (Hypoxia), and inflammation-sensitized hypoxia (LPS+Hypoxia) in an NE piglet model. METHODS: Sixteen piglets were randomized: (i) LPS 2 µg/kg bolus; 1 µg/kg infusion (LPS; n = 5), (ii) Saline with hypoxia (Hypoxia; n = 6), (iii) LPS commencing 4 h pre-hypoxia (LPS+Hypoxia; n = 5). Total RNA was acquired at baseline, 4 h after LPS and 1, 3, 6, 12, 24, 48 h post-insult (animals euthanized at 48 h). Quantitative PCR was performed for cytokines (IL1A, IL6, CXCL8, IL10, TNFA) and brain biomarkers (ENO2, UCHL1, S100B, GFAP, CRP, BDNF, MAPT). MicroRNA was detected using GeneChip (Affymetrix) microarrays. Fold changes from baseline were compared between groups and correlated with cell death (TUNEL) at 48 h. RESULTS: Within 6 h post-insult, we observed increased IL1A, CXCL8, CCL2 and ENO2 mRNA in LPS+Hypoxia and LPS compared to Hypoxia. IL10 mRNA differentiated all groups. Four microRNAs differentiated LPS+Hypoxia and Hypoxia: hsa-miR-23a, 27a, 31-5p, 193-5p. Cell death correlated with TNFA (R = 0.69; p < 0.01) at 1-3 h and ENO2 (R = -0.69; p = 0.01) at 48 h. CONCLUSIONS: mRNA and miRNA differentiated hypoxia from inflammation-sensitized hypoxia within 6 h in a piglet model. This information may inform human studies to enable triage for tailored neuroprotection in NE. IMPACT: Early stratification of infants with neonatal encephalopathy is key to providing tailored neuroprotection. IL1A, CXCL8, IL10, CCL2 and NSE mRNA are promising biomarkers of inflammation-sensitized hypoxia. IL10 mRNA levels differentiated all three pathological states; fold changes from baseline was the highest in LPS+Hypoxia animals, followed by LPS and Hypoxia at 6 h. miR-23, -27, -31-5p and -193-5p were significantly upregulated within 6 h of a hypoxia insult. Functional analysis highlighted the diverse roles of miRNA in cellular processes.


Asunto(s)
Citocinas/genética , Hipoxia-Isquemia Encefálica/sangre , Inflamación/sangre , MicroARNs/sangre , ARN Mensajero/sangre , Animales , Animales Recién Nacidos , Biomarcadores , Encéfalo/patología , Quimiocinas/biosíntesis , Quimiocinas/genética , Citocinas/biosíntesis , Modelos Animales de Enfermedad , Endotoxemia/sangre , Endotoxemia/inducido químicamente , Regulación de la Expresión Génica , Ontología de Genes , Humanos , Hipoxia-Isquemia Encefálica/patología , Inflamación/genética , Lipopolisacáridos/toxicidad , Masculino , Proteínas del Tejido Nervioso/biosíntesis , Proteínas del Tejido Nervioso/genética , Fosfopiruvato Hidratasa/biosíntesis , Fosfopiruvato Hidratasa/genética , Distribución Aleatoria , Encefalopatía Asociada a la Sepsis/sangre , Encefalopatía Asociada a la Sepsis/inducido químicamente , Encefalopatía Asociada a la Sepsis/patología , Porcinos , Factores de Tiempo , Análisis de Matrices Tisulares , Factor de Necrosis Tumoral alfa/biosíntesis , Factor de Necrosis Tumoral alfa/genética
6.
Sci Rep ; 9(1): 10184, 2019 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-31308390

RESUMEN

Co-existing infection/inflammation and birth asphyxia potentiate the risk of developing neonatal encephalopathy (NE) and adverse outcome. In a newborn piglet model we assessed the effect of E. coli lipopolysaccharide (LPS) infusion started 4 h prior to and continued for 48 h after hypoxia on brain cell death and systemic haematological changes compared to LPS and hypoxia alone. LPS sensitized hypoxia resulted in an increase in mortality and in brain cell death (TUNEL positive cells) throughout the whole brain, and in the internal capsule, periventricular white matter and sensorimotor cortex. LPS alone did not increase brain cell death at 48 h, despite evidence of neuroinflammation, including the greatest increases in microglial proliferation, reactive astrocytosis and cleavage of caspase-3. LPS exposure caused splenic hypertrophy and platelet count suppression. The combination of LPS and hypoxia resulted in the highest and most sustained systemic white cell count increase. These findings highlight the significant contribution of acute inflammation sensitization prior to an asphyxial insult on NE illness severity.


Asunto(s)
Encefalopatías/fisiopatología , Lesiones Encefálicas/fisiopatología , Hipoxia-Isquemia Encefálica/metabolismo , Animales , Animales Recién Nacidos , Asfixia/metabolismo , Asfixia Neonatal/fisiopatología , Encéfalo/metabolismo , Encefalopatías/metabolismo , Lesiones Encefálicas/metabolismo , Muerte Celular , Modelos Animales de Enfermedad , Escherichia coli , Hipoxia/metabolismo , Hipoxia/fisiopatología , Inflamación/metabolismo , Lipopolisacáridos/efectos adversos , Lipopolisacáridos/farmacología , Masculino , Porcinos , Sustancia Blanca/metabolismo
7.
Neurobiol Dis ; 121: 240-251, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30300675

RESUMEN

Therapeutic hypothermia is only partially protective for neonatal encephalopathy; there is an urgent need to develop treatments that augment cooling. Our objective was to assess safety, efficacy and pharmacokinetics of 5 and 15 mg/kg/24 h melatonin (proprietary formulation) administered at 2 h and 26 h after hypoxia-ischemia (HI) with cooling in a piglet model. Following moderate cerebral HI, 30 piglets were eligible and randomized to: i) Hypothermia (33.5 °C, 2-26 h) and vehicle (HT + V;n = 13); b) HT and 5 mg/kg melatonin over 6 h at 2 h and 26 h after HI (HT + Mel-5;n = 4); c) HT and 15 mg/kg melatonin over 6 h at 2 h and 26 h after HI (HT + Mel-15;n = 13). Intensive care was maintained for 48 h; brain MRS was acquired and cell death (TUNEL) evaluated at 48 h. Comparing HT + V with HT + Mel-5 and HT + Mel-15, there was no difference in blood pressure or inotropic support needed, brain Lactate/N Acetylaspartate at 24 h and 48 h was similar, ATP/phosphate pool was higher for HT + Mel-15 versus HT + V at 24 h (p = 0.038) but not 48 h. A localized reduction in TUNEL positive cell death was observed in the sensorimotor cortex in the 15 mg/kg melatonin group (HT + Mel-15 versus HT + V; p < 0.003) but not in the 5 mg/kg melatonin group (HT + Mel-5 versus HT + V; p = 0.808). Putative therapeutic melatonin levels were reached 8 h after HI (104 increase from baseline; ~15-30 mg/l). Mean ±â€¯SD peak plasma melatonin levels after the first infusion were 0.0014 ±â€¯0.0012 mg/l in the HT + V group, 3.97 ±â€¯1.53 mg/l in the HT + Mel-5 group and 16.8 ±â€¯8.3 mg/l in the HT + Mel-15 group. Protection was dose dependent; 15 mg/kg melatonin started 2 h after HI, given over 6 h, was well tolerated and augmented hypothermic protection in sensorimotor cortex. Earlier attainment of therapeutic plasma melatonin levels may optimize protection by targeting initial events of reperfusion injury. The time window for intervention with melatonin, as adjunct therapy with cooling, is likely to be narrow and should be considered in designing future clinical studies.


Asunto(s)
Encéfalo/efectos de los fármacos , Hipotermia Inducida/métodos , Hipoxia-Isquemia Encefálica/terapia , Melatonina/uso terapéutico , Fármacos Neuroprotectores/uso terapéutico , Animales , Encéfalo/metabolismo , Modelos Animales de Enfermedad , Hipoxia-Isquemia Encefálica/complicaciones , Hipoxia-Isquemia Encefálica/metabolismo , Melatonina/farmacología , Fármacos Neuroprotectores/farmacología , Sus scrofa , Investigación Biomédica Traslacional
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