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1.
Fitoterapia ; 169: 105568, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37315717

RESUMO

Five new 5-methyl-4-hydroxycoumarin polyketide derivatives (MPDs), delavayicoumarins A-E (1-5), were isolated from the whole plants of Gerbera delavayi. Among them, compounds 1-3 are the common monoterpene polyketide coumarins (MPCs), while 4 is a modified MPC with both the lactone ring contracted to a five-membered furan ring and a carboxyl at C-3, and 5 is a pair of unusual phenylpropanoid polyketide coumarin enantiomers (5a and 5b), featuring a phenylpropanoid unit at C-3. The planar structures were elucidated by spectroscopic methods and biosynthetic arguments, and the absolute configurations of 1-3, 5a and 5b were confirmed by calculated electronic circular dichroism (ECD) experiment. Furthermore, compounds 1-3, (+)-5 and (-)-5 were tested for the nitric oxide (NO) inhibitory activity by using lipopolysaccharide (LPS)-induced RAW 264.7 cells in vitro. The results showed that compounds 1-3, (+)-5 and (-)-5 remarkably inhibited NO production at the concentration of 10.0 µM, exhibiting that they have significant anti-inflammatory activity.


Assuntos
4-Hidroxicumarinas , Asteraceae , Policetídeos , Policetídeos/farmacologia , Estrutura Molecular , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/química , Óxido Nítrico
2.
Rev. méd. Chile ; 151(6): 797-800, jun. 2023. ilus
Artigo em Espanhol | LILACS | ID: biblio-1560243

RESUMO

La intoxicación humana por rodenticidas anticoagulantes de acción prolongada, conocidos como superwarfarinas, provoca coagulopatía de prolongado manejo. Presentamos el caso de un hombre de 42 años que ingirió una dosis tóxica de rodenticida en un intento suicida, evolucionando con epistaxis, INR de 11,6 y necesidad de hospitalización. Durante 7 días se realizaron controles seriados de pruebas de coagulación, con optimización de diferentes dosis de suplementación de Vitamina K. El caso destaca la potencia y vida media prolongada (aproximadamente 6 semanas) de este tipo de anticoagulantes, hecho que requiere un control clínico regular y una adherencia al tratamiento satisfactoria.


Human intoxication by long-acting anticoagulant rodenticides, known as superwarfarins, causes coagulopathy that is difficult to manage. We present the case of a 42-year-old man who ingested a toxic dose of rodenticide in a suicide attempt, evolving with epistaxis, INR of 11.6, and needing hospitalization. For seven days, serial controls of coagulation tests were carried out, with optimization of different doses of Vitamin K supplementation. The case highlights this type of anticoagulant's potency and prolonged half-life (approximately six weeks), which requires regular clinical control and satisfactory treatment adherence.


Assuntos
Humanos , Masculino , Adulto , Rodenticidas/intoxicação , Tentativa de Suicídio , Anticoagulantes/intoxicação , Vitamina K/uso terapêutico , 4-Hidroxicumarinas/intoxicação
3.
Artigo em Chinês | MEDLINE | ID: mdl-36229221

RESUMO

Bromadiolone, commonly known as super warfarin, is a long-acting coumarin dicoumarin rodenticide. The mechanism of bromadiolone is mainly to inhibit vitamin K1 epoxide reductase and affect the synthesis of coagulation factors Ⅱ, Ⅶ, Ⅸ and Ⅹ, which causes blood coagulation dysfunction and systemic multiple organ hemorrhage. Here, we report of a case of bromadiolone poisoning patient who had digestive tract, abdominal hemorrhage, as well as secondary paralytic ileus. After blood product transfusion and vitamin K1 supplementation, the patient was discharged after the physical condition was improved. It's suggestied that clinicians should pay attention to rare complications to prevent missed diagnosis when treating other bromadiolone poisoning.


Assuntos
4-Hidroxicumarinas , Pseudo-Obstrução Intestinal , Rodenticidas , Fatores de Coagulação Sanguínea , Dicumarol , Hemorragia , Humanos , Pseudo-Obstrução Intestinal/induzido quimicamente , Oxirredutases , Vitamina K 1 , Varfarina
4.
Mol Cell Biochem ; 477(2): 525-536, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34816338

RESUMO

The aim of this study was to investigate the beneficial effects of vitamin K relate to protection against detrimental effects of bromadiolone. Wistar rats (n = 30) were divided in three groups (n = 10): control group and two groups treated with bromadiolone (0.12 mg/kg) and bromadiolone + vitamin K (0.12 mg/kg + 100 mg/kg) over the period of four days. The main findings in the bromadiolone-exposed rats, such as damaged hepatocytes, high levels of globulin, total proteins and lymphocytes, and altered albumin/globulin ratio, collectively indicate an acute inflammatory process. Morphological changes in erythrocytes include microcytosis, hypochromia, hyperchromia, hemolysis, stomatocytosis, and spherocytosis. Significantly low values of RBC, Hct, and hemoglobin concentrations indicate impairments of the hematopoietic pathway causing combined anemia. The selected dose of bromadiolone caused a non-significant increase of catalase activity and a significant increase of the total protein content in brain tissue homogenates. Vitamin K supplementation reduced many of the harmful effects of bromadiolone. The cytoprotective role of vitamin K was proved to be of great importance for the preservation of structural changes on the membranes of hepatocytes and erythrocytes, in addition to the known role in the treatment of coagulopathies. The results of the study suggest valuable properties of vitamin K in the prevention and treatment of various types of anemia caused by bromadiolone toxicity. Future research is necessary to determine the adequate dose and treatment duration with vitamin K in disorders caused by the cumulative action of bromadiolone and possibly other pesticides.


Assuntos
4-Hidroxicumarinas , Anticoagulantes , Encéfalo/metabolismo , Fígado/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Rodenticidas , Vitamina K , 4-Hidroxicumarinas/farmacocinética , 4-Hidroxicumarinas/farmacologia , Animais , Anticoagulantes/farmacocinética , Anticoagulantes/farmacologia , Avaliação Pré-Clínica de Medicamentos , Ratos , Ratos Wistar , Rodenticidas/farmacocinética , Rodenticidas/farmacologia , Vitamina K/farmacocinética , Vitamina K/farmacologia
5.
Nutrients ; 13(10)2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34684491

RESUMO

Vitamin K dependent proteins (VKDP), such as hepatic coagulation factors and vascular matrix Gla protein (MGP), play key roles in maintaining physiological functions. Vitamin K deficiency results in inactive VKDP and is strongly linked to vascular calcification (VC), one of the major risk factors for cardiovascular morbidity and mortality. In this study we investigated how two vitamin K surrogate markers, dephosphorylated-undercarboxylated MGP (dp-ucMGP) and protein induced by vitamin K absence II (PIVKA-II), reflect vitamin K status in patients on hemodialysis or with calcific uremic arteriolopathy (CUA) and patients with atrial fibrillation or aortic valve stenosis. Through inter- and intra-cohort comparisons, we assessed the influence of vitamin K antagonist (VKA) use, vitamin K supplementation and disease etiology on vitamin K status, as well as the correlation between both markers. Overall, VKA therapy was associated with 8.5-fold higher PIVKA-II (0.25 to 2.03 AU/mL) and 3-fold higher dp-ucMGP (843 to 2642 pM) levels. In the absence of VKA use, non-renal patients with established VC have dp-ucMGP levels similar to controls (460 vs. 380 pM), while in HD and CUA patients, levels were strongly elevated (977 pM). Vitamin K supplementation significantly reduced dp-ucMGP levels within 12 months (440 to 221 pM). Overall, PIVKA-II and dp-ucMGP showed only weak correlation (r2 ≤ 0.26) and distinct distribution pattern in renal and non-renal patients. In conclusion, VKA use exacerbated vitamin K deficiency across all etiologies, while vitamin K supplementation resulted in a vascular VKDP status better than that of the general population. Weak correlation of vitamin K biomarkers calls for thoughtful selection lead by the research question. Vitamin K status in non-renal deficient patients was not anomalous and may question the role of vitamin K deficiency in the pathogenesis of VC in these patients.


Assuntos
Biomarcadores/sangue , Proteínas de Ligação ao Cálcio/sangue , Proteínas da Matriz Extracelular/sangue , Precursores de Proteínas/sangue , Calcificação Vascular/sangue , Deficiência de Vitamina K/sangue , Vitamina K/sangue , 4-Hidroxicumarinas/uso terapêutico , Estenose da Valva Aórtica/sangue , Estenose da Valva Aórtica/complicações , Fibrilação Atrial/sangue , Fibrilação Atrial/complicações , Doenças Cardiovasculares/etiologia , Estudos de Coortes , Suplementos Nutricionais , Feminino , Fatores de Risco de Doenças Cardíacas , Humanos , Indenos/uso terapêutico , Fígado/metabolismo , Masculino , Pessoa de Meia-Idade , Estado Nutricional , Protrombina , Diálise Renal/efeitos adversos , Uremia/sangue , Uremia/complicações , Calcificação Vascular/complicações , Vitamina K/antagonistas & inibidores , Vitamina K/uso terapêutico , Deficiência de Vitamina K/complicações , Proteína de Matriz Gla
6.
Ann Palliat Med ; 10(6): 7008-7012, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33183018

RESUMO

Bromadiolone, a widely-used rodent control drug, could act as a long-acting anticoagulant. Patients of bromadiolone poisoning often present with multiorgan hemorrhage. However, neurological symptoms of bromadiolone poisoning are seldom reported. We report a rare case with convulsive status epilepticus as the initial presentation of bromadiolone poisoning. A previously healthy 18-year-old man presented with persistent unconsciousness and repeated convulsive seizures. Magnetic resonance imaging revealed lesions in the corpus callosum. Laboratory test revealed the microscopic hematuria, prolonged prothrombin time, prolonged activated partial thromboplastin time and the presence of bromadiolone. The patient was diagnosed as the bromadiolone poisoning and treated with hemofiltration, vitamin K and prothrombin complex. Consciousness of the patient was regained and all neurological symptoms diminished after 7 days. Coagulopathy was totally corrected after 3 weeks, and a 2-month regimen of vitamin K supplementation was prescribed after discharge. Our case suggests that bromadiolone poisoning may involve the central nervous system. The atypical and initial symptoms of neurological disorders might lead to misdiagnosis of bromadiolone poisoning. Poisoning should be considered when acute neurological symptoms are combined with bleeding tendency. The vitamin K treatment is effective for both coagulopathy and central nervous system disorders in bromadiolone poisoning.


Assuntos
Rodenticidas , Estado Epiléptico , 4-Hidroxicumarinas , Anticoagulantes , Hemorragia , Humanos , Estado Epiléptico/induzido quimicamente
7.
Ann Biol Clin (Paris) ; 78(6): 639-646, 2020 Dec 01.
Artigo em Francês | MEDLINE | ID: mdl-33258456

RESUMO

Type 2 heparin-induced thrombocytopenia (HIT 2) is a rare pro-thrombotic disorder occurring in patients treated with heparin. It is defined as a clinical-biological syndrome associating the sudden onset of a thrombocytopenia, characterized by a drop of more than 50% of the initial platelet count, and thrombosis. We report two cases of HIT 2 occurring in patients with major bleeding tendency. The first HIT occurred in a patient whose management, in accordance with current guidelines, made it possible to control the thrombocytopenia and the anticoagulation despite the complexity of adapting and monitoring treatments in the context of recent cerebral hemorrhage. The second refers to an autoimmune HIT, which occurred in a patient whose management required the use of alternative therapies to the standard treatments suggested for HIT 2, to correct the severe refractory thrombocytopenia.


Assuntos
Transtornos da Coagulação Sanguínea/terapia , Hemorragia/prevenção & controle , Heparina/efeitos adversos , Trombocitopenia/induzido quimicamente , Trombocitopenia/terapia , 4-Hidroxicumarinas/administração & dosagem , Idoso , Anticoagulantes/efeitos adversos , Arginina/administração & dosagem , Arginina/análogos & derivados , Transtornos da Coagulação Sanguínea/complicações , Relação Dose-Resposta a Droga , Esquema de Medicação , Quimioterapia Combinada , Hemorragia/etiologia , Humanos , Indenos/administração & dosagem , Trombose Intracraniana/tratamento farmacológico , Trombose Intracraniana/etiologia , Trombose Intracraniana/cirurgia , Masculino , Pessoa de Meia-Idade , Procedimentos Neurocirúrgicos/métodos , Ácidos Pipecólicos/administração & dosagem , Sulfonamidas/administração & dosagem , Vitamina K/administração & dosagem , Vitamina K/antagonistas & inibidores
8.
Molecules ; 25(21)2020 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-33171577

RESUMO

Coumarins, which occur naturally in the plant kingdom, are diverse class of secondary metabolites. With their antiproliferative, chemopreventive and antiangiogenetic properties, they can be used in the treatment of cancer. Their therapeutic potential depends on the type and location of the attachment of substituents to the ring. Therefore, the aim of our study was to investigate the effect of simple coumarins (osthole, umbelliferone, esculin, and 4-hydroxycoumarin) combined with sorafenib (specific inhibitor of Raf (Rapidly Accelerated Fibrosarcoma) kinase) in programmed death induction in human glioblastoma multiforme (T98G) and anaplastic astrocytoma (MOGGCCM) cells lines. Osthole and umbelliferone were isolated from fruits: Mutellina purpurea L. and Heracleum leskowii L., respectively, while esculin and 4-hydroxycoumarin were purchased from Sigma Aldrich (St. Louis, MO, USA). Apoptosis, autophagy and necrosis were identified microscopically after straining with specific fluorochromes. The level of caspase 3, Beclin 1, PI3K (Phosphoinositide 3-kinase), and Raf kinases were estimated by immunoblotting. Transfection with specific siRNA (small interfering RNA) was used to block Bcl-2 (B-cell lymphoma 2), Raf, and PI3K expression. Cell migration was tested with the wound healing assay. The present study has shown that all the coumarins eliminated the MOGGCCM and T98G tumor cells mainly via apoptosis and, to a lesser extent, via autophagy. Osthole, which has an isoprenyl moiety, was shown to be the most effective compound. Sorafenib did not change the proapoptotic activity of this coumarin; however, it reduced the level of autophagy. At the molecular level, the induction of apoptosis was associated with a decrease in the expression of PI3K and Raf kinases, whereas an increase in the level of Beclin 1 was observed in the case of autophagy. Inhibition of the expression of this protein by specific siRNA eliminated autophagy. Moreover, the blocking of the expression of Bcl-2 and PI3K significantly increased the level of apoptosis. Osthole and sorafenib successfully inhibited the migration of the MOGGCCM and T98G cells.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Cumarínicos/farmacologia , Glioblastoma/tratamento farmacológico , Magnoliopsida/química , Extratos Vegetais/farmacologia , Sorafenibe/farmacologia , 4-Hidroxicumarinas/farmacologia , Antineoplásicos Fitogênicos/isolamento & purificação , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Proteína Beclina-1/genética , Proteína Beclina-1/metabolismo , Caspase 3/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Esculina/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Necrose/tratamento farmacológico , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , RNA Interferente Pequeno/metabolismo , Umbeliferonas/farmacologia , Quinases raf/metabolismo
9.
Leg Med (Tokyo) ; 47: 101772, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32771937

RESUMO

A 50-year-old man was admitted to the emergency department with abrupt massive epistaxis. An accurate anamnesis and physical evaluation could not reveal any other anomalies, while coagulation tests showed potentially life threatening prolonged prothrombin time, with activated partial thromboplastin and thrombin time, with fibrinogen and antithrombin III within limits. Despite the prompt pharmacological and compressive local treatment, bleeding continued and the patient was therefore hospitalized. Highly specific coagulation and toxicological testing-among others high-performance liquid chromatography assessment on plasma-were performed, leading to the unexpected identification of brodifacoum. Police and criminal justice authorities revealed the source of exposure to brodifacoum after several months of investigation, residing in his everyday life. Brodifacoum is a long-lasting anticoagulant, acting as a vitamin K antagonist, and belongs to the family of superwarfarins. Brodifacoum use is authorized as rodenticide in many countries worldwide, but has been reported as cause of severe coagulopathies in humans, both intentional or involuntary, even consumed as a contaminant of herbal drugs, such as cannabis. The original contribution of this case to the knowledges of human brodifacoum intoxication resides in the multidisciplinary approach and the collaborative interplay of clinical and toxicology experts as well as judicial authorities.


Assuntos
4-Hidroxicumarinas/intoxicação , Acidentes , Anticoagulantes/intoxicação , Epistaxe/etiologia , Medicina Legal , Rodenticidas/intoxicação , 4-Hidroxicumarinas/sangue , Anticoagulantes/sangue , Cromatografia Líquida de Alta Pressão , Homicídio , Humanos , Masculino , Pessoa de Meia-Idade , Rodenticidas/sangue
10.
Blood ; 136(7): 898-908, 2020 08 13.
Artigo em Inglês | MEDLINE | ID: mdl-32374827

RESUMO

Drug-induced bleeding disorders contribute to substantial morbidity and mortality. Antithrombotic agents that cause unintended bleeding of obvious cause are relatively easy to control. However, the mechanisms of most drug-induced bleeding disorders are poorly understood, which makes intervention more difficult. As most bleeding disorders are associated with the dysfunction of coagulation factors, we adapted our recently established cell-based assay to identify drugs that affect the biosynthesis of active vitamin K-dependent (VKD) coagulation factors with possible adverse off-target results. The National Institutes of Health (NIH) Clinical Collection (NCC) library containing 727 drugs was screened, and 9 drugs were identified, including the most commonly prescribed anticoagulant warfarin. Bleeding complications associated with most of these drugs have been clinically reported, but the pathogenic mechanisms remain unclear. Further characterization of the 9 top-hit drugs on the inhibition of VKD carboxylation suggests that warfarin, lansoprazole, and nitazoxanide mainly target vitamin K epoxide reductase (VKOR), whereas idebenone, clofazimine, and AM404 mainly target vitamin K reductase (VKR) in vitamin K redox cycling. The other 3 drugs mainly affect vitamin K availability within the cells. The molecular mechanisms underlying the inactivation of VKOR and VKR by these drugs are clarified. Results from both cell-based and animal model studies suggest that the anticoagulation effect of drugs that target VKOR, but not VKR, can be rescued by the administration of vitamin K. These findings provide insights into the prevention and management of drug-induced bleeding disorders. The established cell-based, high-throughput screening approach provides a powerful tool for identifying new vitamin K antagonists that function as anticoagulants.


Assuntos
Anticoagulantes/isolamento & purificação , Anticoagulantes/farmacologia , Transtornos Hemorrágicos/induzido quimicamente , Ensaios de Triagem em Larga Escala/métodos , Vitamina K/metabolismo , 4-Hidroxicumarinas/efeitos adversos , 4-Hidroxicumarinas/isolamento & purificação , 4-Hidroxicumarinas/farmacologia , Animais , Anticoagulantes/efeitos adversos , Coagulação Sanguínea/efeitos dos fármacos , Técnicas de Cultura de Células/métodos , Avaliação Pré-Clínica de Medicamentos/métodos , Células HEK293 , Células Hep G2 , Humanos , Indenos/efeitos adversos , Indenos/isolamento & purificação , Indenos/farmacologia , Masculino , Redes e Vias Metabólicas/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos BALB C , Uso Off-Label , Vitamina K/efeitos adversos , Vitamina K/antagonistas & inibidores , Vitamina K/isolamento & purificação , Vitamina K/farmacologia , Vitamina K Epóxido Redutases/antagonistas & inibidores , Vitamina K Epóxido Redutases/metabolismo
11.
Clin Toxicol (Phila) ; 58(7): 716-724, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-31736367

RESUMO

Background: An outbreak of synthetic cannabinoid (SC)-associated coagulopathy and bleeding in Illinois, USA was determined to be due to inhalation of SC contaminated with brodifacoum (BDF), difenacoum (DiF), and bromadiolone (BDL), highly potent long-acting anticoagulant rodenticides (LAARs). Treatment with high-dose vitamin K1 (VK1) prevented mortality; however, plasma LAAR levels were not measured risking recurrence of coagulopathy and bleeding due to premature discontinuation. The goal of this study was to determine if plasma LAAR levels were reduced following standard of care treatment to normalize coagulopathy.Methods: Blood samples were collected from a cohort of 32 patients, and ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) analysis used to quantify plasma LAAR levels including enantiomers.Results: BDF was detected in 31 samples; 30 also contained DiF and 18 contained BDL. Initial plasma levels were 581 ± 87, 11.0 ± 1.9, and 14.9 ± 5.9 ng/mL for BDF, DiF, and BDL, respectively (mean ± SE). At discharge plasma, BDF levels remained elevated at 453 ± 68 ng/mL. Plasma half-lives for BDF, DiF, and BDL were 7.5 ± 1.3, 7.2 ± 1.9, and 1.8 ± 0.3 days, respectively. The half-life for trans-BDF enantiomers (5.7 ± 0.8 days) was shorter than for cis-enantiomers (7.6 ± 1.9 days). BDF half-lives were shorter, and coagulopathy normalized faster in patients receiving intravenous VK1 as compared to oral VK1. Patients prescribed VK1 at discharge had fewer re-admittances.Conclusions: These results demonstrate that plasma LAAR levels at discharge were elevated in poisoned patients despite normal coagulation, and that the route of VK1 administration affected LAAR pharmacokinetics and INR normalization. We propose plasma LAAR levels and coagulation be monitored concomitantly during follow-up of patients with LAAR poisoning. KEY POINTSIn patients treated with high-dose vitamin K1 for LAAR poisoning, plasma levels remained 40-fold above safe levels upon discharge from hospital.LAAR half-lives, normalization of coagulopathy, and readmittances were reduced by treatment with intravenous vitamin K1.


Assuntos
Anticoagulantes/intoxicação , Canabinoides/química , Hemorragia/tratamento farmacológico , Rodenticidas/intoxicação , Vitamina K 1/administração & dosagem , 4-Hidroxicumarinas/farmacocinética , 4-Hidroxicumarinas/intoxicação , Administração por Inalação , Adulto , Anticoagulantes/farmacocinética , Transtornos da Coagulação Sanguínea/induzido quimicamente , Transtornos da Coagulação Sanguínea/tratamento farmacológico , Cromatografia Líquida de Alta Pressão , Contaminação de Medicamentos , Feminino , Hemorragia/induzido quimicamente , Humanos , Illinois , Masculino , Pessoa de Meia-Idade , Rodenticidas/farmacocinética , Estereoisomerismo , Espectrometria de Massas em Tandem , Adulto Jovem
12.
Lung ; 197(3): 349-352, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31004190

RESUMO

A large-scale outbreak of life-threatening, inhaled synthetic cannabinoids (Spice/K2)-associated coagulopathy with bleeding complications was recently reported in Illinois. The causative agents were brodifacoum, difenacoum, and bromadiolone, potent, long-acting, 4-hydroxycoumarin anticoagulant rodenticides (LAAR) that were mixed with Spice/K2 products procured and then inhaled by the victims. We report on 3 poisoned patients who reside in underserved, socioeconomically disadvantaged neighborhoods of Chicago that were admitted and treated successfully at two inner-city, tertiary care hospitals in Chicago. The patients were discharged from the hospitals on daily long-term high-dose oral vitamin K1 (VK1), provided free of charge. However, 2 patients were lost to follow-up prior to safe discontinuation of oral VK1 therapy. The third patient was treated and followed successfully for 7 months when VK1 was discontinued. We conclude that prolonged oral VK1 therapy and follow-up of acute, life-threatening LAAR poisoning are variable and present challenges to healthcare providers. Appropriate practice guidelines to improve patient access and adherence to daily high-dose oral VK1 therapy and follow-up should be developed and implemented.


Assuntos
Anticoagulantes/intoxicação , Antifibrinolíticos/administração & dosagem , Transtornos da Coagulação Sanguínea/tratamento farmacológico , Canabinoides , Hemorragia/tratamento farmacológico , Cooperação do Paciente , Vitamina K 1/administração & dosagem , 4-Hidroxicumarinas/intoxicação , Administração por Inalação , Adulto , Assistência ao Convalescente , Antifibrinolíticos/uso terapêutico , Transtornos da Coagulação Sanguínea/induzido quimicamente , Chicago , Feminino , Hemorragia/induzido quimicamente , Humanos , Coeficiente Internacional Normatizado , Perda de Seguimento , Masculino , Adesão à Medicação , Pessoa de Meia-Idade , Medicamentos Sintéticos , Vitamina K 1/uso terapêutico
13.
Drugs R D ; 19(1): 67-71, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30689138

RESUMO

A recent multi-state outbreak of life-threatening bleeding following inhalation of synthetic cannabinoids has been attributed to contamination with the long-acting anticoagulant rodenticide (LAAR) brodifacoum, a second-generation, highly potent, long-acting derivative of the commonly used blood thinner warfarin. While long-term treatment with high-dose vitamin K1 restores coagulation, it does not affect brodifacoum metabolism or clearance, and, consequently, brodifacoum remains in the human body for several months, thereby predisposing to risk of bleeding recurrence and development of coagulation-independent injury in extrahepatic tissues and fetuses. This has prompted the evaluation of pharmacological measures that accelerate brodifacoum clearance from poisoned patients. Since the induction of certain cytochrome P450 (CYP) enzymes accelerates warfarin metabolism, using CYP inducers, such as phenobarbital, to accelerate brodifacoum clearance seems plausible. However, unlike warfarin, brodifacoum does not undergo significant metabolism in the liver, nor have the effects of phenobarbital on vitamin K1 metabolism been previously determined. In addition, the safety of phenobarbital in brodifacoum-poisoned patients has not been established. Therefore, we propose that CYP inducers should not be used to accelerate the clearance of brodifacoum from poisoned patients, but that alternative approaches such as reducing enterohepatic recirculation of brodifacoum, or using lipid emulsions to scavenge brodifacoum throughout the body, be considered.


Assuntos
4-Hidroxicumarinas/farmacocinética , 4-Hidroxicumarinas/intoxicação , Indutores das Enzimas do Citocromo P-450/administração & dosagem , Anticoagulantes/administração & dosagem , Coagulação Sanguínea/efeitos dos fármacos , Circulação Êntero-Hepática/efeitos dos fármacos , Emulsões Gordurosas Intravenosas , Meia-Vida , Hemorragia/induzido quimicamente , Hemorragia/tratamento farmacológico , Hemorragia/metabolismo , Humanos , Inativação Metabólica/efeitos dos fármacos , Vitamina K/administração & dosagem
14.
Emerg Radiol ; 25(6): 715-718, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30022308

RESUMO

Synthetic marijuana is a dangerous substance due to its potency, ever-changing composition, and unpredictable side effects. Recently, brodifacoum-contaminated synthetic marijuana has led to multiple deaths and morbidity throughout the USA from severe coagulopathy associated with use of this strain of the drug (brodifacoum is a rodenticide and potent Vitamin K antagonist/anticoagulant). We describe the clinical and radiologic findings in two patients who were diagnosed with, and treated for, ingestion of this new strain of synthetic marijuana. The radiologic manifestations were most notable for hemorrhagic pyelitis/ureteritis. Both patients required hospitalization with Vitamin K supplementation. The radiologic and clinical pictures in these patients are important for radiologists to recognize in order to help guide appropriate patient management.


Assuntos
4-Hidroxicumarinas/intoxicação , Transtornos da Coagulação Sanguínea/induzido quimicamente , Transtornos da Coagulação Sanguínea/diagnóstico por imagem , Canabinoides/intoxicação , Surtos de Doenças , Drogas Ilícitas/intoxicação , Intoxicação/diagnóstico por imagem , Rodenticidas/intoxicação , Adulto , Baltimore/epidemiologia , Transtornos da Coagulação Sanguínea/tratamento farmacológico , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Intoxicação/tratamento farmacológico , Tomografia Computadorizada por Raios X , Vitamina K/uso terapêutico
15.
Forensic Sci Int ; 267: 129-135, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27598867

RESUMO

Brodifacoum is one of the most widely used rodenticides for rodent control and eradication; however, human and animal poisoning due to primary and secondary exposure has been reported since its development. Although numerous studies have described brodifacoum induced toxicity, the precise mechanism still needs to be explored. Gas chromatography mass spectrometry (GC-MS) coupled with an ultra performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) was applied to characterize the metabolic profile of brodifacoum induced toxicity and discover potential biomarkers in rat plasma. The toxicity of brodifacoum was dose-dependent, and the high-dose group obviously manifested toxicity with subcutaneous hemorrhage. The blood brodifacoum concentration showed a positive relation to the ingestion dose in toxicological analysis. Significant changes of twenty-four metabolites were identified and considered as potential toxicity biomarkers, primarily involving glucose metabolism, lipid metabolism and amino acid metabolism associated with anticoagulant activity, nephrotoxicity and hepatic damage. MS-based metabonomics analysis in plasma samples is helpful to search for potential poisoning biomarkers and to understand the underlying mechanisms of brodifacoum induced toxicity.


Assuntos
4-Hidroxicumarinas/sangue , 4-Hidroxicumarinas/toxicidade , Rodenticidas/sangue , Rodenticidas/toxicidade , Aminoácidos/metabolismo , Animais , Peso Corporal/efeitos dos fármacos , Cromatografia Líquida , Análise Discriminante , Cromatografia Gasosa-Espectrometria de Massas , Glucose/metabolismo , Metabolismo dos Lipídeos , Metabolômica , Análise Multivariada , Análise de Componente Principal , Ratos Wistar , Espectrometria de Massas em Tandem
16.
J Enzyme Inhib Med Chem ; 31(2): 219-28, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-25815669

RESUMO

A series of novel 3-substituted amino-4-hydroxycoumarin derivatives have been designed and synthesized as chitin synthase (CHS) inhibitors. All the synthesized compounds have been screened for their CHS inhibition activity and antimicrobial activity in vitro. The enzymatic assay indicated that most of the compounds have good inhibitory activity against CHS, in which compound 6o with IC50 of 0.10 mmol/L had stronger activity than that of polyoxins B, which acts as control drug with IC50 of 0.18 mmol/L. As far as the antifungal activity is concerned, most of the compounds possessed moderate to excellent activity against some representative pathogenic fungi. Especially, compound 6b was found to be the most potent agent against Cryptococcus neoformans with minimal inhibitory concentration (MIC) of 4 µg/mL. Moreover, the results of antibacterial screening showed that these compounds have negligible actions to some tested bacteria. Therefore, these compounds would be promising to develop selective antifungal agents.


Assuntos
4-Hidroxicumarinas/química , Antifúngicos/química , Antifúngicos/farmacologia , Quitina Sintase/antagonistas & inibidores , Inibidores Enzimáticos/farmacologia , Antibacterianos/química , Antibacterianos/farmacologia , Antifúngicos/síntese química , Técnicas de Química Sintética , Cryptococcus neoformans/efeitos dos fármacos , Avaliação Pré-Clínica de Medicamentos/métodos , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Concentração Inibidora 50 , Testes de Sensibilidade Microbiana , Relação Estrutura-Atividade
17.
Lab Med ; 47(1): 63-6, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26715613

RESUMO

Exposure to brodifacoum, a superwarfarin substance, can lead to severe coagulopathic manifestations. Brodifacoum is a lipophilic, vitamin K antagonist with a long half-life. Clinical manifestations are challenging to diagnose if the patient cannot provide information regarding exposure. Herein, we report the first case in the literature, to our knowledge, of a patient who had intentionally inhaled brodifacoum. We performed coagulation studies such as prothrombin time (PT) and international normalized ratio (INR) to monitor vitamin K dependent coagulation factors in the patient, a 21-year-old Caucasian man. On admission to the hospital, the INR of the patient was 12.9; a computed tomography (CT) angiogram detected a mediastinal hemorrhage. In the absence of 4-factor PCC, the patient received 30 plasma transfusions during a 4-day period due to persistent left pleural effusions, along with vitamin K therapy to normalize his coagulation factors. His high-performance liquid chromatography (HPLC) results on hospital day 3 and day 26 confirmed the presence of brodifacoum in his body. We believe that inhalation led the poison to bypass the initial metabolism process of the liver, resulting in rapid anticoagulation and subsequent bleeding diathesis. Management of brodifacoum poisoning is case dependent on the amount of exposure and INR status. Constant INR monitoring, large dose vitamin K therapy and initial plasma transfusions (in the absence of PCC) were able to prevent severe internal bleeding in the patient.


Assuntos
4-Hidroxicumarinas/toxicidade , Anticoagulantes/toxicidade , Inalação , Intoxicação/diagnóstico , Intoxicação/terapia , Transfusão de Componentes Sanguíneos , Humanos , Coeficiente Internacional Normatizado , Masculino , População Branca , Adulto Jovem
18.
J Pharm Pharmacol ; 67(4): 573-82, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25556550

RESUMO

OBJECTIVES: Due to the increasing prevalence of drug-resistant Staphylococcus aureus infection, we develop novel 4-hydroxycoumarin derivatives as antimicrobials. METHODS: The antibacterial activity of 4-hydroxycoumarin derivatives against drug-susceptive S. aureus (ATCC 29213) and methicillin-resistant S. aureus (MRSA) were evaluated using minimal inhibitory concentration (MIC) assay; the activity of favourable compound was further observed using bacterial growth curves assay and in the MRSA infection mice. KEY FINDINGS: Compared with dihydropyran derivatives, compound 1 as one of biscoumarins showed most potent activity with MIC values of 4-8 µg/ml and apparently inhibited the growth rate of S. aureus ATCC 29213 and USA300 strain in concentrations of both 16 and 32 mg/ml. In the mice infected with MRSA USA300, administration of 5 mg/kg compound 1 improved the animal survival rate to 66.7%, and improved the pathological change in lung tissue compared with the infection model animals. No significant cytotoxicity of compound 1 was observed on the umbilical vein endothelial cells (HUVECs) under the concentration of 800 µg/ml. CONCLUSION: Compared with the dihydropyran derivatives, biscoumarins exhibited more promising activity against both drug-sensitive and drug-resistant S. aureus, and it is efficacious in treating MRSA infections in mouse models with a favourable safety in human cells.


Assuntos
4-Hidroxicumarinas/uso terapêutico , Antibacterianos/uso terapêutico , Pneumopatias/tratamento farmacológico , Pulmão/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Infecções Estafilocócicas/tratamento farmacológico , 4-Hidroxicumarinas/biossíntese , 4-Hidroxicumarinas/farmacologia , Animais , Antibacterianos/farmacologia , Células Endoteliais da Veia Umbilical Humana , Pulmão/microbiologia , Pulmão/patologia , Pneumopatias/microbiologia , Pneumopatias/patologia , Camundongos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus
20.
Am J Health Syst Pharm ; 71(8): 639-42, 2014 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-24688037

RESUMO

PURPOSE: A case of brodifacoum exposure leading to coagulopathy lasting for approximately one year despite treatment with large doses of phytonadione is reported. SUMMARY: A 36-year-old man was diagnosed with severe coagulopathy. He was treated and discharged on 40 mg of oral phytonadione daily. The cause of the coagulopathy remained unknown at discharge, but the hematologist theorized that exposure to a vitamin K antagonist was likely the source of the patient's condition. The patient was rehospitalized one week later with an International Normalized Ratio (INR) of 5.9 despite self-reported medication compliance. Oral phytonadione was increased to 80 mg daily. The patient was seen at an outpatient hematology clinic for several months and continued on tapering dosages of oral phytonadione. A coagulopathy panel from the original hospitalization confirmed the presence of brodifacoum, though the method of exposure remained unclear. He was lost to follow-up until approximately nine months later, when he reported taking 10 mg daily of oral phytonadione and had an INR of 1. Oral phytonadione was discontinued. Two months later, his INR was greater than 9, despite an undetectable level of brodifacoum. He was rehospitalized with oropharyngeal hematoma approximately 1 year after the initial coagulopathy diagnosis. The patient was discharged on 40 mg oral phytonadione daily with outpatient follow-up. CONCLUSION: A patient with brodifacoum exposure ingested brodifacoum had coagulopathy that lasted approximately one year despite long-term treatment with large dosages of oral phytonadione. The coagulopathy persisted even when brodifacoum was undetectable in the serum. Long-term treatment with high-dose phytonadione is expensive, which may influence medication compliance.


Assuntos
4-Hidroxicumarinas/intoxicação , Anticoagulantes/intoxicação , Transtornos da Coagulação Sanguínea/induzido quimicamente , Rodenticidas/intoxicação , Adulto , Antifibrinolíticos/administração & dosagem , Antifibrinolíticos/uso terapêutico , Transtornos da Coagulação Sanguínea/tratamento farmacológico , Transtornos da Coagulação Sanguínea/fisiopatologia , Seguimentos , Humanos , Coeficiente Internacional Normatizado , Masculino , Índice de Gravidade de Doença , Fatores de Tempo , Vitamina K 1/administração & dosagem , Vitamina K 1/uso terapêutico
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