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1.
Sci Rep ; 14(1): 7786, 2024 04 02.
Artículo en Inglés | MEDLINE | ID: mdl-38565581

RESUMEN

In multiple sclerosis (MS), alterations of the gut microbiota lead to inflammation. However, the role of other microbiomes in the body in MS has not been fully elucidated. In a pilot case-controlled study, we carried out simultaneous characterization of faecal and oral microbiota and conducted an in-depth analysis of bacterial alterations associated with MS. Using 16S rRNA sequencing and metabolic inference tools, we compared the oral/faecal microbiota and bacterial metabolism pathways in French MS patients (n = 14) and healthy volunteers (HV, n = 21). A classification model based on metabolite flux balance was established and validated in an independent German cohort (MS n = 12, HV n = 38). Our analysis revealed decreases in diversity indices and oral/faecal compartmentalization, the depletion of commensal bacteria (Aggregatibacter and Streptococcus in saliva and Coprobacter and Roseburia in faeces) and enrichment of inflammation-associated bacteria in MS patients (Leptotrichia and Fusobacterium in saliva and Enterobacteriaceae and Actinomyces in faeces). Several microbial pathways were also altered (the polyamine pathway and remodelling of bacterial surface antigens and energetic metabolism) while flux balance analysis revealed associated alterations in metabolite production in MS (nitrogen and nucleoside). Based on this analysis, we identified a specific oral metabolite signature in MS patients, that could discriminate MS patients from HV and rheumatoid arthritis patients. This signature allowed us to create and validate a discrimination model on an independent cohort, which reached a specificity of 92%. Overall, the oral and faecal microbiomes were altered in MS patients. This pilot study highlights the need to study the oral microbiota and oral health implications in patients with autoimmune diseases on a larger scale and suggests that knowledge of the salivary microbiome could help guide the identification of new pathogenic mechanisms associated with the microbiota in MS patients.


Asunto(s)
Microbiota , Esclerosis Múltiple , Humanos , Proyectos Piloto , ARN Ribosómico 16S/genética , ARN Ribosómico 16S/análisis , Microbiota/genética , Bacterias/genética , Inflamación
2.
Hum Immunol ; : 110790, 2024 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-38575482

RESUMEN

Currently, the genetic variants strongly associated with risk for Multiple Sclerosis (MS) are located in the Major Histocompatibility Complex. This includes DRB1*15:01 and DRB1*15:03 alleles at the HLA-DRB1 locus, the latter restricted to African populations; the DQB1*06:02 allele at the HLA-DQB1 locus which is in high linkage disequilibrium (LD) with DRB1*15:01; and protective allele A*02:01 at the HLA-A locus. HLA allele identification is facilitated by co-inherited ('tag') single nucleotide polymorphisms (SNPs); however, SNP validation is not typically done outside of the discovery population. We examined 19 SNPs reported to be in high LD with these alleles in 2,502 healthy subjects included in the 1000 Genomes panel having typed HLA data. Examination of 3 indices (LD R2 values, sensitivity and specificity, minor allele frequency) revealed few SNPs with high tagging performance. All SNPs examined that tag DRB1*15:01 were in perfect LD in the British population; three showed high tagging performance in 4 of the 5 European, and 2 of the 4 American populations. For DQB1*06:02, with no previously validated tag SNPs, we show that rs3135388 has high tagging performance in one South Asian, one American, and one European population. We identify for the first time that rs2844821 has high tagging performance for A*02:01 in 5 of 7 African populations including African Americans, and 4 of the 5 European populations. These results provide a basis for selecting SNPs with high tagging performance to assess HLA alleles across diverse populations, for MS risk as well as for other diseases and conditions.

3.
Toxicol Sci ; 2024 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-38603617

RESUMEN

Administration of high dose vitamin K1 (VK1) overcomes coagulopathy and bleeding elicited by acute poisoning with long-acting anti-coagulant rodenticides (LAARs). However, long-term (months) treatment is required due to long LAAR biological half-lives that may lead to poor compliance and recurrent coagulopathy. The half-lives of LAARs are extended by slow metabolism, and similar to warfarin, are thought to undergo enterohepatic recirculation. We now show that treatment with the bile acid sequestrant cholestyramine (CSA) administered concomitantly with VK1 decreases plasma LAAR levels and increases LAAR fecal excretion. Daily CSA treatment for 14 days did not reduce plasma VK1 levels, nor increase prothrombin time. Collectively, these data show that CSA accelerates LAAR clearance from rabbits without adverse effects on VK1 anti-coagulation, and could provide an additional therapeutic option for treatment of LAAR poisoning.

4.
Neurosci Lett ; 815: 137497, 2023 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-37748675

RESUMEN

Roles for lipocalin-2 (LCN2, also referred to as neutrophil gelatinase associated lipocalin, NGAL) in the progression of disease in multiple sclerosis and its animal models have been reported; however, the importance of astrocyte-derived LCN2, a major source of LCN2, have not been defined. We found that clinical scores in experimental autoimmune encephalomyelitis (EAE) were modestly delayed in mice with conditional knockout of LCN2 from astrocytes, associated with a small decrease in astrocyte GFAP expression. Immunostaining and qPCR of spinal cord samples showed decreased oligodendrocyte proteolipid protein and transcription factor Olig2 expression, but no changes in PDGFRα expression. These results suggest astrocyte LCN2 contributes to early events in EAE and reduces damage to mature oligodendrocytes at later times.


Asunto(s)
Encefalomielitis Autoinmune Experimental , Esclerosis Múltiple , Ratones , Animales , Lipocalina 2/genética , Lipocalina 2/metabolismo , Esclerosis Múltiple/metabolismo , Astrocitos/metabolismo , Proteínas de Fase Aguda/genética , Proteínas de Fase Aguda/metabolismo , Lipocalinas/genética , Lipocalinas/metabolismo , Encefalomielitis Autoinmune Experimental/metabolismo , Modelos Animales de Enfermedad , Oligodendroglía/metabolismo , ARN Mensajero/metabolismo , Ratones Endogámicos C57BL
5.
J Neuroimmunol ; 382: 578152, 2023 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-37454525

RESUMEN

The c-Jun amino terminal kinases (JNKs) regulate transcription, and studies suggest they contribute to neuropathology in the EAE model of MS. To examine the role of the JNK3 isoform, we compared EAE in JNK3 null mice to wild type (WT) littermates. Although disease severity was similar in female mice, in male JNK3 null mice the day of onset and time to reach 100% incidence occurred sooner, and disease severity was increased. While glial activation in spinal cord was similar, white matter lesions were increased in JNK3 null mice. These results suggest JNK3 normally limits EAE disease in a sex-dependent manner.


Asunto(s)
Proteína Quinasa 10 Activada por Mitógenos , Esclerosis Múltiple , Animales , Femenino , Masculino , Ratones , Proteínas Quinasas JNK Activadas por Mitógenos/genética , Proteínas Quinasas JNK Activadas por Mitógenos/metabolismo , Proteína Quinasa 10 Activada por Mitógenos/genética , Proteína Quinasa 10 Activada por Mitógenos/metabolismo , Esclerosis Múltiple/genética , Esclerosis Múltiple/metabolismo , Gravedad del Paciente , Fosforilación , Factores Sexuales
6.
Nat Neurosci ; 26(4): 532-533, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36879143
7.
Acta Biomater ; 158: 782-797, 2023 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-36638942

RESUMEN

Mesenchymal stem cell (MSCs)-derived extracellular vesicles (EVs) are emerging therapeutic tools. Hypoxic pre-conditioning (HPC) of MSCs altered the production of microRNAs (miRNAs) in EVs, and enhanced the cytoprotective, anti-inflammatory, and neuroprotective properties of their derivative EVs in retinal cells. EV miRNAs were identified as the primary contributors of these EV functions. Through miRNA seq analyses, miRNA-424 was identified as a candidate for the retina to overexpress in EVs for enhancing cytoprotection and anti-inflammatory effects. FEEs (functionally engineered EVs) overexpressing miR424 (FEE424) significantly enhanced neuroprotection and anti-inflammatory activities in vitro in retinal cells. FEE424 functioned by reducing inflammatory cytokine production in retinal microglia, and attenuating oxygen free radicals in retinal Muller cells and microvascular endothelial cells, providing a multi-pronged approach to enhancing recovery after retinal ischemic insult. In an in vivo model of retinal ischemia, native, HPC, and FEE424 MSC EVs robustly and similarly restored function to close to baseline, and prevented loss of retinal ganglion cells, but HPC EVs provided the most effective attenuation of apoptosis-related and inflammatory cytokine gene expression. These results indicate the potential for EV engineering to produce ameliorative effects for retinal diseases with a significant inflammatory component. STATEMENT OF SIGNIFICANCE: We show that functionally engineered extracellular vesicles (FEEs) from mesenchymal stem cells (MSCs) provide cytoprotection in rat retina subjected to ischemia. FEEs overexpressing microRNA 424 (FEE424) function by reducing inflammatory cytokine production in retinal microglia, and attenuating oxygen free radicals in Muller cells and microvascular endothelial cells, providing a multi-pronged approach to enhancing recovery. In an in vivo model of retinal ischemia in rats, native, hypoxic-preconditioned (HPC), and FEE424 MSC EVs robustly and similarly restored function, and prevented loss of retinal ganglion cells, but HPC EVs provided the most effective attenuation of apoptosis-related and inflammatory cytokine gene expression. The results indicate the potential for EV engineering to produce ameliorative effects for retinal diseases with a significant inflammatory component.


Asunto(s)
Vesículas Extracelulares , Células Madre Mesenquimatosas , MicroARNs , Enfermedades de la Retina , Ratas , Animales , MicroARNs/genética , MicroARNs/metabolismo , Células Endoteliales/metabolismo , Isquemia/terapia , Citocinas/metabolismo , Enfermedades de la Retina/metabolismo , Antiinflamatorios , Hipoxia , Vesículas Extracelulares/metabolismo , Células Madre Mesenquimatosas/metabolismo
8.
Alzheimers Dement (N Y) ; 8(1): e12358, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36313967

RESUMEN

Introduction: Olfactory impairment in older individuals is associated with an increased risk of Alzheimer's disease (AD). Characterization of age versus neuropathology-associated changes in the brain olfactory pathway may elucidate processes underlying early AD pathogenesis. Here, we report age versus AD neuropathology-associated differential transcription in four brain regions in the olfactory pathway of 10 female African green monkeys (vervet, Chlorocebus aethiops sabaeus), a well-described model of early AD-like neuropathology. Methods: Transcriptional profiles were determined by microarray in the olfactory bulb (OB), piriform cortex (PC), temporal lobe white matter (WM), and inferior temporal cortex (ITC). Amyloid beta (Aß) plaque load in parietal and temporal cortex was determined by immunohistochemistry, and concentrations of Aß42, Aß40, and norepinephrine in ITC were determined by enzyme-linked immuosorbent assay (ELISA). Transcriptional profiles were compared between middle-aged and old animals, and associations with AD-relevant neuropathological measures were determined. Results: Transcriptional profiles varied by brain region and age group. Expression levels of TRO and RNU4-1 were significantly lower in all four regions in the older group. An additional 29 genes were differentially expressed by age in three of four regions. Analyses of a combined expression data set of all four regions identified 77 differentially expressed genes (DEGs) by age group. Among these DEGs, older subjects had elevated levels of CTSB , EBAG9, LAMTOR3, and MRPL17, and lower levels of COMMD10 and TYW1B. A subset of these DEGs was associated with neuropathology biomarkers. Notably, CTSB was positively correlated with Aß plaque counts, Aß42:Aß40 ratios, and norepinephrine levels in all brain regions. Discussion: These data demonstrate age differences in gene expression in olfaction-associated brain regions. Biological processes exhibiting age-related enrichment included the regulation of cell death, vascular function, mitochondrial function, and proteostasis. A subset of DEGs was specifically associated with AD phenotypes. These may represent promising targets for future mechanistic investigations and perhaps therapeutic intervention.

9.
ASN Neuro ; 14: 17590914221112352, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35791633

RESUMEN

Although over 20 disease modifying therapies are approved to treat Multiple Sclerosis (MS), these do not increase remyelination of demyelinated axons or mitigate axon damage. Previous studies showed that lanthionine ketenamine ethyl ester (LKE) reduces clinical signs in the experimental autoimmune encephalomyelitis (EAE) mouse model of MS and increased maturation of oligodendrocyte (OL) progenitor cells (OPCs) in vitro. In the current study, we used the cuprizone (CPZ) demyelination model of MS to test if LKE could increase remyelination. The corpus callosum (CC) and somatosensory cortex was examined by immunohistochemistry (IHC), electron microscopy and for mRNA expression changes in mice provided 5 weeks of CPZ diet followed by 2 weeks of normal diet in the presence of LKE or vehicle. A significant increase in the number of myelinated axons, and increased myelin thickness was observed in the CC of LKE-treated groups compared to vehicle-treated groups. LKE also increased myelin basic protein and proteolipid protein expression in the CC and cortex, and increased the number of mature OLs in the cortex. In contrast, LKE did not increase the percentage of proliferating OPCs suggesting effects on OPC survival and differentiation but not proliferation. The effects of LKE on OL maturation and remyelination were supported by similar changes in their relative mRNA levels. Interestingly, LKE did not have significant effects on GFAP or Iba1 immunostaining or mRNA levels. These findings suggest that remyelinating actions of LKE can potentially be formulated to induce remyelination in neurological diseases associated with demyelination including MS.


Asunto(s)
Encefalomielitis Autoinmune Experimental , Esclerosis Múltiple , Remielinización , Aminoácidos Sulfúricos , Animales , Cuprizona/toxicidad , Modelos Animales de Enfermedad , Encefalomielitis Autoinmune Experimental/tratamiento farmacológico , Ésteres/farmacología , Ratones , Esclerosis Múltiple/tratamiento farmacológico , ARN Mensajero
11.
Brain Behav Immun ; 103: 163-170, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35439553

RESUMEN

Peripheral inflammation is elevated in older Black adults, an elevation which prior work has suggested may be due to chronic stress associated with systemic racism and related adverse cardiovascular health conditions. Inflammation is also involved in the pathogenic processes of dementia; however, limited (and mixed) results exist concerning inflammation and cognitive decline in Black adults. We characterized patterns of inflammation and their role in cognitive decline in 280 older Black adults (age = 72.99 ± 6.00 years; 69.6% female) from the Minority Aging Research Study (MARS) who were without dementia at baseline and followed between 2 and 15 years (mean = 9 years). Participants completed a blood draw at baseline and annual cognitive evaluations. Serum was assayed for 9 peripheral inflammatory markers; 19 neuropsychological test scores were used to create indices of global cognition and five cognitive domains. Principal component analysis with varimax rotation characterized patterns of inflammation with factor loadings > 0.6 per component contributing to two composite scores representing acute/upstream and chronic/downstream inflammation. These composites were used as separate predictors in linear mixed regression models to determine associations with level and change in cognition adjusting for relevant covariates. Higher baseline upstream/acute inflammation associated with lower baseline semantic memory (p = .040) and perceptual speed (p = .046); it was not related to cognitive decline. By contrast, higher baseline downstream/chronic inflammation associated with faster declines in global cognition (p = .010), episodic (p = .027) and working memory (p = .006); it was not related to baseline cognition. For older Black adults, chronic, but not acute, inflammation may be a risk factor for changes in cognition.


Asunto(s)
Disfunción Cognitiva , Demencia , Adulto , Negro o Afroamericano , Anciano , Cognición , Disfunción Cognitiva/psicología , Femenino , Gerociencia , Humanos , Inflamación , Masculino , Pruebas Neuropsicológicas
12.
J Neuroimmunol ; 364: 577810, 2022 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-35066333

RESUMEN

Previous studies showed that depleting Liver Kinase-B1 (LKB1) from astrocytes increased inflammatory factors lipocalin-2 (LCN2) and osteopontin (OPN) in EAE. A single nucleotide polymorphism (SNP) in STK11 (encoding LKB1) is a risk factor for MS, suggesting increased LCN2 or OPN contributes to risk. Serum LCN2 and OPN levels in African American female MS patients were higher than healthy controls, and while levels increased with disease duration in cases without the SNP, levels decreased with duration in cases with the SNP. Increased MS risk associated with the STK11 SNP may be due to higher LCN2 or OPN levels at early times.


Asunto(s)
Quinasas de la Proteína-Quinasa Activada por el AMP/genética , Lipocalina 2/sangre , Esclerosis Múltiple Recurrente-Remitente/sangre , Esclerosis Múltiple Recurrente-Remitente/genética , Adulto , Negro o Afroamericano/genética , Biomarcadores/sangre , Progresión de la Enfermedad , Femenino , Predisposición Genética a la Enfermedad/genética , Humanos , Persona de Mediana Edad , Osteopontina/sangre , Polimorfismo de Nucleótido Simple
13.
Pain ; 163(2): e368-e381, 2022 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-35029600

RESUMEN

ABSTRACT: Mechanistic studies principally focusing on primary afferent nociceptive neurons uncovered the upregulation of collapsin response mediator protein 2 (CRMP2)-a dual trafficking regulator of N-type voltage-gated calcium (Cav2.2) as well as Nav1.7 voltage-gated sodium channels-as a potential determinant of neuropathic pain. Whether CRMP2 contributes to aberrant excitatory synaptic transmission underlying neuropathic pain processing after peripheral nerve injury is unknown. Here, we interrogated CRMP2's role in synaptic transmission and in the initiation or maintenance of chronic pain. In rats, short-interfering RNA-mediated knockdown of CRMP2 in the spinal cord reduced the frequency and amplitude of spontaneous excitatory postsynaptic currents, but not spontaneous inhibitory postsynaptic currents, recorded from superficial dorsal horn neurons in acute spinal cord slices. No effect was observed on miniature excitatory postsynaptic currents and inhibitory postsynaptic currents. In a complementary targeted approach, conditional knockout of CRMP2 from mouse neurons using a calcium/calmodulin-dependent protein kinase II alpha promoter to drive Cre recombinase expression reduced the frequency and amplitude of spontaneous excitatory postsynaptic currents, but not miniature excitatory SCss. Conditional knockout of CRMP2 from mouse astrocytes using a glial fibrillary acidic protein promoter had no effect on synaptic transmission. Conditional knockout of CRMP2 in neurons reversed established mechanical allodynia induced by a spared nerve injury in both male and female mice. In addition, the development of spared nerve injury-induced allodynia was also prevented in these mice. Our data strongly suggest that CRMP2 is a key regulator of glutamatergic neurotransmission driving pain signaling and that it contributes to the transition of physiological pain into pathological pain.


Asunto(s)
Astrocitos , Neuralgia , Animales , Femenino , Masculino , Ratones , Neuralgia/genética , Neuralgia/metabolismo , Neuronas/metabolismo , Nocicepción , Ratas , Transmisión Sináptica
14.
Toxicol Commun ; 5(1): 93-96, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34458660

RESUMEN

The importance of real-time, quantitative toxicology data available for physicians treating poisoned patients was illustrated during the 2018 outbreak in Illinois of severe coagulopathy caused by inhaling illicit synthetic cannabinoids products contaminated with commercially-available brodifacoum, difenacoum, and bromadiolone, three potent, long-acting anticoagulant rodenticides (LAARs). Identification and quantification of these life-threatening toxins in blood samples of hospitalized patients required toxicology testing with liquid chromatography-tandem mass spectrometry (LC-MS/MS) that was not available in clinical laboratories of hospitals at the time of the outbreak. This highly-sensitive, quantitative assay can provide critical information to guide patient care during and after hospitalization, including identification of offending LAARs, estimates of the ingested dose, and dosage and discontinuation of oral vitamin K1 therapy after hospital discharge once plasma LAARs concentrations decreased to a safe level (<10 ng/mL). Accordingly, we propose an action plan to enable treating physicians to quantify plasma concentrations of several LAARs simultaneously in poisoned patients. It involves rapid (<15 min), sensitive, and validated LC-MS/MS methods developed, tested and validated in our laboratory. This will allow treating physicians to request quantitative plasma LAARs testing, report test results in the patient's hospital discharge summary, and recommend regular monitoring of plasma LAARs concentrations in the outpatient setting.

15.
Mult Scler Relat Disord ; 55: 103185, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34371271

RESUMEN

BACKGROUND: We previously reported that the single nucleotide polymorphism (SNP) rs9282860 in serine threonine kinase 11 (STK11) gene which codes for liver kinase B1 (LKB1) has higher prevalence in White relapsing-remitting multiple sclerosis (RRMS) patients than controls. However it is not known if this SNP is a risk factor for MS in other populations. METHODS: We assessed the prevalence of the STK11 SNP in samples collected from African American (AA) persons with MS (PwMS) and controls at multiple Veterans Affairs (VA) Medical Centers and from a network of academic MS centers. Genotyping was carried out using a specific Taqman assay. Comparisons of SNP frequencies were made using Fisher's exact test to determine significance and odds ratios. Group means were compared by appropriate t-tests based on normality and variance using SPSS V27. RESULTS: There were no significant differences in average age at first symptom onset, age at diagnosis, disease duration, or disease severity between RRMS patients recruited from VAMCs versus non-VAMCs. The SNP was more prevalent in AA than White PwMS, however only in secondary progressive MS (SPMS) patients was that difference statistically significant. AA SPMS patients had higher STK11 SNP prevalence than controls; and in that cohort the SNP was associated with older age at symptom onset and at diagnosis. CONCLUSIONS: The results suggest that the STK11 SNP represents a risk factor for SPMS in AA patients, and can influence both early (onset) and later (conversion to SPMSS) events.


Asunto(s)
Esclerosis Múltiple Crónica Progresiva , Esclerosis Múltiple Recurrente-Remitente , Esclerosis Múltiple , Negro o Afroamericano/genética , Anciano , Humanos , Hígado , Esclerosis Múltiple/epidemiología , Esclerosis Múltiple/genética , Esclerosis Múltiple Recurrente-Remitente/epidemiología , Esclerosis Múltiple Recurrente-Remitente/genética , Polimorfismo de Nucleótido Simple/genética , Proteínas Serina-Treonina Quinasas/genética
16.
Cells ; 10(4)2021 03 25.
Artículo en Inglés | MEDLINE | ID: mdl-33806128

RESUMEN

Cell replacement therapy using mesenchymal (MSC) and other stem cells has been evaluated for diabetic retinopathy and glaucoma. This approach has significant limitations, including few cells integrated, aberrant growth, and surgical complications. Mesenchymal Stem Cell Exosomes/Extracellular Vesicles (MSC EVs), which include exosomes and microvesicles, are an emerging alternative, promoting immunomodulation, repair, and regeneration by mediating MSC's paracrine effects. For the clinical translation of EV therapy, it is important to determine the cellular destination and time course of EV uptake in the retina following administration. Here, we tested the cellular fate of EVs using in vivo rat retinas, ex vivo retinal explant, and primary retinal cells. Intravitreally administered fluorescent EVs were rapidly cleared from the vitreous. Retinal ganglion cells (RGCs) had maximal EV fluorescence at 14 days post administration, and microglia at 7 days. Both in vivo and in the explant model, most EVs were no deeper than the inner nuclear layer. Retinal astrocytes, microglia, and mixed neurons in vitro endocytosed EVs in a dose-dependent manner. Thus, our results indicate that intravitreal EVs are suited for the treatment of retinal diseases affecting the inner retina. Modification of the EV surface should be considered for maintaining EVs in the vitreous for prolonged delivery.


Asunto(s)
Vesículas Extracelulares/metabolismo , Células Madre Mesenquimatosas/metabolismo , Retina/citología , Animales , Astrocitos/citología , Astrocitos/metabolismo , Fluorescencia , Humanos , Inyecciones Intravítreas , Cinética , Células Madre Mesenquimatosas/citología , Microglía/citología , Microglía/metabolismo , Ratas , Células Ganglionares de la Retina/citología , Células Ganglionares de la Retina/metabolismo , Neuronas Retinianas/citología , Neuronas Retinianas/metabolismo , Coloración y Etiquetado
17.
Toxicol Commun ; 5(1): 69-72, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33768191

RESUMEN

Standard of care follow-up therapy for patients poisoned by long-acting anticoagulant rodenticides (LAARs) is daily high-dose (up to 100 mg per day) oral vitamin K1 (VK1) for weeks to months to over a year. The availability of CLIA-certified quantitative testing for plasma LAAR concentrations can now assist health care providers in determining when to safely discontinue VK1 therapy. We present estimates of treatment duration required to reach safe concentrations (< =10ng/ml) using serial measurements of plasma brodifacoum (BDF, a potent LAAR) concentrations obtained from patients poisoned after inhaling synthetic cannabinoids containing BDF. We fit the data to zero-order (linear) and first-order (exponential) curves, the latter to account for enterohepatic circulation of BDF. The results show that estimates of therapy duration are significantly longer when exponential clearance is assumed. Accordingly, we recommend that plasma BDF concentrations be monitored simultaneously with international normalization ratio (INR) during follow-up of poisoned patients, and that concentrations be determined after VK1 therapy is discontinued to document persistence of safe concentrations.

18.
Artículo en Inglés | MEDLINE | ID: mdl-33486217

RESUMEN

Superwarfarins are second-generation long-acting anticoagulant rodenticides that can cause unintended human and wildlife toxicity due, in part, to their prolonged half-lives. Commercially available superwarfarin rodenticides are synthesized as racemates with two asymmetric carbons, producing four stereoisomers. To support studies of human plasma half-lives of individual superwarfarin stereoisomers, a method was developed based on LC-MS/MS to separate and quantify stereoisomers of the commercially important superwarfarins bromadiolone, difenacoum and brodifacoum. Human plasma samples were prepared using protein precipitation and centrifugation. Chiral-phase HPLC separation was carried out on-line with tandem mass spectrometric quantitative analysis of the eluting stereoisomers using selected-reaction monitoring with positive ion electrospray on a triple quadrupole mass spectrometer. All four stereoisomers of each superwarfarin were resolved within 12.5 min with calibration curves spanning 2-3 orders of magnitude and lower limits of quantitation between 0.87 and 2.55 ng/mL. This method was used to determine the half-lives of superwarfarin stereoisomers in plasma from patients who had inhaled synthetic cannabinoid products contaminated with superwarfarins. These data may be used to guide the development of safer next generation anticoagulant rodenticides stereoisomers.


Asunto(s)
4-Hidroxicumarinas/sangre , Cromatografía Líquida de Alta Presión/métodos , Rodenticidas/sangre , Espectrometría de Masas en Tándem/métodos , 4-Hidroxicumarinas/química , Adulto , Femenino , Humanos , Límite de Detección , Modelos Lineales , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Rodenticidas/química , Estereoisomerismo , Adulto Joven
19.
West J Emerg Med ; 22(4): 1014-1019, 2021 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-35354010

RESUMEN

INTRODUCTION: Synthetic cannabinoids are a rapidly expanding subset of designer drugs widely available in the United States since 2008. In Illinois during the spring of 2018, over 160 documented cases of bleeding and prolonged coagulopathy occurred secondary to contaminated synthetic cannabinoids. METHODS: We conducted a retrospective cohort study consisting of 38 patients to describe the initial emergency department (ED) presentation, diagnosis, and treatment. RESULTS: Through serum testing we found that three long-acting anticoagulant rodenticides (LAAR) were detected in patients who had inhaled these tainted products: brodifacoum, difenacoum, and bromodialone. DISCUSSION: This study encompasses the largest ED presentation of LAAR poisoning via the inhalational route known to date. CONCLUSION: The emergency physician should be aware of the potential for tainted coingestants as the cause of undifferentiated coagulopathy.


Asunto(s)
Cannabinoides , Rodenticidas , Cannabinoides/efectos adversos , Servicio de Urgencia en Hospital , Humanos , Estudios Retrospectivos , Rodenticidas/envenenamiento , Estados Unidos , Vitamina K
20.
J AOAC Int ; 103(3): 770-778, 2020 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-33241367

RESUMEN

BACKGROUND: Superwarfarins, second-generation long-acting anticoagulant rodenticides, are 4-hydroxycoumarin analogues of warfarin that contain a large hydrophobic side chain. These compounds contain two chiral centers and are synthesized for commercial use as two pairs of diastereomer. OBJECTIVE: To support studies of superwarfarin pharmacokinetics and other efforts to improve clinical care for poisoning victims, a quantitative assay was developed for the measurement of diastereomer of bromadiolone, difenacoum, flocoumafen, brodifacoum, and difethialone in human plasma. METHOD: Based on ultrahigh-pressure liquid chromatography-tandem mass-spectrometry (UHPLC-MS/MS), this method was validated according to U.S. Food and Drug Administration (FDA) guidelines. Sample preparation involved simple protein precipitation followed by reversed phase UHPLC, which resolved all five pairs of cis/trans diastereomer in less than 10 min. Superwarfarins were measured using negative ion electrospray followed by selected-reaction monitoring on a triple quadrupole mass spectrometer. RESULTS: Calibration curves covered 3-4 orders of magnitude with linear regression coefficients of >0.999. The lower limits of quantitation were from 0.013 to 2.41 ng/mL, and intra-day and inter-day accuracy and precision coefficients of variation were <12%. CONCLUSIONS: A 10-min UHPLC-MS/MS assay was developed and validated for the separation and quantitative analysis of the pairs of diastereomer of five superwarfarins in human plasma. HIGHLIGHTS: This method was used to identify and measure superwarfarins and their cis/trans diastereomers in plasma obtained from patients treated for coagulopathy following consumption of contaminated synthetic cannabinoid products.


Asunto(s)
4-Hidroxicumarinas , Rodenticidas , 4-Hidroxicumarinas/análisis , Anticoagulantes , Cromatografía Líquida de Alta Presión , Humanos , Reproducibilidad de los Resultados , Rodenticidas/análisis , Espectrometría de Masas en Tándem
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