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1.
Toxicol Sci ; 200(1): 137-145, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38603617

RESUMO

Administration of high-dose vitamin K1 (VK1) overcomes coagulopathy and bleeding elicited by acute poisoning with long-acting anticoagulant 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, or increase prothrombin time. Collectively, these data show that CSA accelerates LAAR clearance from rabbits without adverse effects on VK1 anticoagulation, and could provide an additional therapeutic option for treatment of LAAR poisoning.


Assuntos
Anticoagulantes , Coagulação Sanguínea , Resina de Colestiramina , Fezes , Rodenticidas , Vitamina K 1 , Animais , Coelhos , Rodenticidas/farmacocinética , Rodenticidas/sangue , Anticoagulantes/administração & dosagem , Anticoagulantes/farmacocinética , Vitamina K 1/sangue , Vitamina K 1/administração & dosagem , Coagulação Sanguínea/efeitos dos fármacos , Masculino , Fezes/química , Meia-Vida , Tempo de Protrombina , Taxa de Depuração Metabólica
2.
BMC Pregnancy Childbirth ; 24(1): 229, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38566061

RESUMO

BACKGROUND: Maternal obesity is associated with adverse outcome for pregnancy and childbirths. While bariatric surgery may improve fertility and reduce the risk of certain pregnancy-related complications such as hypertension and gestational diabetes mellitus, there is a lack of evidence on the optimal nutritional monitoring and supplementation strategies in pregnancy following bariatric surgery. We aimed to assess the impact of bariatric surgery on micronutrients in post-bariatric pregnancy and possible differences between gastric bypass surgery and sleeve gastrectomy. METHODS: In this prospective case control study, we recruited 204 pregnant women (bariatric surgery n = 59 [gastric bypass surgery n = 26, sleeve gastrectomy n = 31, missing n = 2] and controls n = 145) from Akershus university hospital in Norway. Women with previous bariatric surgery were consecutively invited to study participation at referral to the clinic for morbid obesity and the controls were recruited from the routine ultrasound screening in gestational week 17-20. A clinical questionnaire was completed and blood samples were drawn at mean gestational week 20.4 (SD 4.5). RESULTS: The women with bariatric surgery had a higher pre-pregnant BMI than controls (30.8 [SD 6.0] vs. 25.2 [5.4] kg/m2, p < 0.001). There were no differences between groups regarding maternal weight gain (bariatric surgery 13.3 kg (9.6) vs. control 14.8 kg (6.5), p = 0.228) or development of gestational diabetes (n = 3 [5%] vs. n = 7 [5%], p = 1.000). Mean levels of vitamin K1 was lower after bariatric surgery compared with controls (0.29 [0.35] vs. 0.61 [0.65] ng/mL, p < 0.001). Multiadjusted regression analyses revealed an inverse relationship between bariatric surgery and vitamin K1 (B -0.26 ng/mL [95% CI -0.51, -0.04], p = 0.047) with a fivefold increased risk of vitamin K1 deficiency in post-bariatric pregnancies compared with controls (OR 5.69 [1.05, 30.77] p = 0.044). Compared with sleeve gastrectomy, having a previous gastric bypass surgery was associated with higher risk of vitamin K1 deficiency (OR 17.1 [1.31, 223.3], p = 0.030). CONCLUSION: Post-bariatric pregnancy is negatively associated with vitamin K1 with a higher risk of vitamin K1 deficiency in pregnancies after gastric bypass surgery compared with after sleeve gastrectomy. Vitamin K1 deficiency in post-bariatric pregnancy have potential risk of hypocoaguble state in mother and child and should be explored in future studies.


Assuntos
Cirurgia Bariátrica , Derivação Gástrica , Obesidade Mórbida , Complicações na Gravidez , Criança , Feminino , Humanos , Gravidez , Estudos de Casos e Controles , Derivação Gástrica/efeitos adversos , Vitamina K 1 , Obesidade Mórbida/complicações , Obesidade Mórbida/cirurgia , Cirurgia Bariátrica/efeitos adversos , Complicações na Gravidez/etiologia
3.
Nutr Metab Cardiovasc Dis ; 34(5): 1189-1197, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38342722

RESUMO

BACKGROUND AND AIMS: Assessing the relationship between vitamin K1 intakes, using region-specific food databases, with both all-cause, and cardiovascular disease (CVD) mortality warrants further investigation to inform future preventative strategies. Consequently, we examined the aforementioned associations in the Perth Longitudinal Study of Ageing Women (PLSAW). METHODS AND RESULTS: 1436 community-dwelling older Australian women (mean ± SD age 75.2 ± 2.7 years) completed a validated food frequency questionnaire at baseline (1998). Vitamin K1 intake was calculated based on an Australian vitamin K food database, supplemented with published data. All-cause and CVD mortality data was obtained from linked health records. Associations were examined using restricted cubic splines within Cox-proportional hazard models, adjusted for a range of cardiovascular and lifestyle related risk factors. Over 15 years of follow-up, 601 (41.9%) women died, with 236 deaths (16.4%) due to CVD. Compared to women with the lowest vitamin K1 intakes (Quartile 1, median 49.1 µg/day), those with the highest intakes (Quartile 4, median 119.3 µg/day) had lower relative hazards for all-cause mortality (HR 0.66 95%CI 0.51-0.86) and CVD mortality (HR 0.61 95%CI 0.41-0.92). A plateau in the inverse association was observed from vitamin K1 intakes of approximately ≥80 µg/day. CONCLUSION: Higher vitamin K1 intakes were associated with lower risk for both all-cause and CVD mortality in community-dwelling older women, independent of CVD related risk factors. A higher intake of vitamin K1 rich foods, such as leafy green vegetables, may support cardiovascular health.


Assuntos
Doenças Cardiovasculares , Humanos , Feminino , Idoso , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/prevenção & controle , Vitamina K 1 , Estudos Longitudinais , Vida Independente , Estudos Prospectivos , Austrália/epidemiologia , Fatores de Risco
4.
Artigo em Alemão | MEDLINE | ID: mdl-38412953

RESUMO

OBJECTIVE: In this retrospective study, patient records of dogs suffering from poisoning with coumarin derivatives were evaluated to characterize the clinical appearance more precisely. MATERIAL UND METHODS: Retrospective data analysis included 52 dogs with hemostaseologically proven anticoagulant rodenticide poisoning which were treated as inpatients at the Clinic for Small Animals between September 2011 and October 2018. RESULTS: In only 2 dogs (4%) the intake of poison could be observed with certainty. The most common clinical signs observed were reduced general behavior (79%), pallor of the mucosa (79%), anorexia (60%), and dyspnea/tachypnea (60%). In contrast, macroscopically visible internal and external bleedings occurred less frequently. Initially, all cases showed a highly altered prothrombin time and most patients a considerably prolonged activated partial thromboplastin time. Anemia was present in 75% of patients. All dogs included in the study received initially an intravenous treatment with 10 mg/kg vitamin K1. Pretreatment with 1 mg/kg prednisolone was given for prophylaxis of possible incompatibility reactions. No patient showed signs of anaphylactic reaction. Transfusions of whole blood or concentrated red cells were given to only 10 of the 52 animals; only one received 2 transfusions of erythrocytes. 94% of the animals could be discharged home for outpatient therapy after a median length of hospitalization of 3 days (1-9 days) with physiological or almost physiological coagulation test results. CONCLUSION: Anticoagulant rodenticide poisoning is often associated with non-specific symptoms and good prognosis if treated adequately. CLINICAL RELEVANCE: Coagulation diagnostics is always indicated in cases with unclear disorders. In life-threatening emergencies, immediate intravenous infusion of high-dose vitamin K1 is a very effective treatment and results in a rapid increase in coagulation factor activity.


Assuntos
Doenças do Cão , Intoxicação , Rodenticidas , Humanos , Cães , Animais , Anticoagulantes , Estudos Retrospectivos , Doenças do Cão/induzido quimicamente , Doenças do Cão/diagnóstico , Vitamina K 1 , Intoxicação/veterinária
5.
Food Funct ; 15(4): 2170-2180, 2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38312068

RESUMO

Vitamin K isoforms are known as co-factors for the synthesis of blood-clotting proteins, but several other bioactivities were reported. In this work, we isolated a vitamin K1-analogue (OH-PhQ) from the cyanobacterium Tychonema sp. LEGE 07196 with lipid reducing activity. OH-PhQ reduced neutral lipid reservoirs with an EC50 value of 31 µM after 48 h exposure in zebrafish larvae, while other vitamin K isoforms had EC50 values of 21.1 µM (K2) and 1.2 µM (K3). No lipid reducing activity was observed for K1 up to 50 µM. The presence of vitamin K isoforms was studied in zebrafish after exposure (OH-PhQ, K1, K2 and K3), and a clear preference for bioconversion was observed to retain K1 and OH-PhQ. Untargeted metabolomics revealed different biological effects for vitamin K isoforms on the subclass and metabolite level, but similarities were present on the compound class level, particularly on the regulation of glycerophospholipids. Our data showed for the first time a lipid reducing activity of OH-PhQ and performed a comparative analysis of vitamin K isoforms, which could be important for the development of future nutraceuticals or food supplements.


Assuntos
Vitamina K , Peixe-Zebra , Animais , Peixe-Zebra/metabolismo , Metabolismo dos Lipídeos , Vitamina K 1/metabolismo , Isoformas de Proteínas/metabolismo , Lipídeos , Vitamina K 2 , Vitamina K 3
6.
J Thromb Haemost ; 22(2): 466-469, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37981048

RESUMO

All newborns need extra phylloquinone (vitamin K1; K1) to prevent vitamin K deficiency bleeding (VKDB). In preterm babies, the main sources are prophylactic K1 given at birth and parenteral and/or enteral feeding thereafter. Preterm babies are at risk of late-onset VKDB if ongoing K1 supplementation is inadequate. For extremely preterm infants fed an exclusive human milk diet, the low K1 content of human milk may predispose them to vitamin K deficiency. Human milk fortification with either bovine milk-derived fortifier or human milk-based fortifier (HMF) made from pooled donor milk is a widely used strategy to improve the micronutrient and growth status of preterm infants. However, the K1 content of HMF is markedly lower than that of bovine-based preparations. We present an unusual case of late-onset VKDB in an extremely preterm infant who received an exclusive human milk diet and HMF and quantify total K1 intake prior to the bleeding.


Assuntos
Leite Humano , Sangramento por Deficiência de Vitamina K , Lactente , Recém-Nascido , Humanos , Lactente Extremamente Prematuro , Sangramento por Deficiência de Vitamina K/prevenção & controle , Vitamina K 1 , Dieta , Vitamina K
7.
Eur J Clin Invest ; 54(4): e14141, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38071415

RESUMO

BACKGROUND/AIM: Late vitamin K deficiency bleeding (VKDB) during early infancy is a serious problem worldwide. Vitamin K (VK) deficiency commonly occurs in newborns who are exclusively breastfed. Protein Induced by VK Absence (PIVKA-II) has been identified as an early indicator of subclinical VK deficiency in neonates, surpassing prothrombin time. To assess PIVKA-II levels at 48 h, 1 and 3 months of age in full-term newborns who were exclusively breastfed and received varying VKDB prophylaxis regimens. METHODS: A prospective observational study was conducted in four hospitals, enrolling 105 newborns. PIVKA-II levels were measured using a sandwich-type enzyme-linked immunosorbent assay. RESULTS: At 48 h of age, there was no significant difference in PIVKA-II concentrations between newborns who received intramuscular administration of 1 mg of phylloquinone (VK1) and those who received oral administration of 2 mg of VK1 at birth. At 1 and 3 months of life, infants who received any supplementation regimen between 2 and 14 weeks exhibited significantly lower PIVKA-II concentrations compared to infants who received only 1 mg of intramuscular VK1 at birth. The prophylaxis involving a dose of 1 mg of intramuscular VK1 at birth followed by oral administration of 150 µg/day of VK1 from the 2nd to the 14th week of life showed the lowest PIVKA-II blood concentrations. CONCLUSIONS: Oral supplementation of VK1 after discharge significantly reduced PIVKA-II concentrations in exclusively breastfed term infants. These findings suggest the importance of oral VK1 supplementation in exclusively breastfed infants during their first 3 months of life to avoid the risk of VK insufficiency.


Assuntos
Sangramento por Deficiência de Vitamina K , Vitamina K , Lactente , Feminino , Recém-Nascido , Humanos , Protrombina/metabolismo , Precursores de Proteínas , Biomarcadores/metabolismo , Vitamina K 1 , Sangramento por Deficiência de Vitamina K/prevenção & controle
8.
Plant Cell ; 36(4): 1140-1158, 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38124486

RESUMO

Chlorophyll degradation causes the release of phytol, which is converted into phytyl diphosphate (phytyl-PP) by phytol kinase (VITAMIN E PATHWAY GENE5 [VTE5]) and phytyl phosphate (phytyl-P) kinase (VTE6). The kinase pathway is important for tocopherol synthesis, as the Arabidopsis (Arabidopsis thaliana) vte5 mutant contains reduced levels of tocopherol. Arabidopsis harbors one paralog of VTE5, farnesol kinase (FOLK) involved in farnesol phosphorylation. Here, we demonstrate that VTE5 and FOLK harbor kinase activities for phytol, geranylgeraniol, and farnesol with different specificities. While the tocopherol content of the folk mutant is unchanged, vte5-2 folk plants completely lack tocopherol. Tocopherol deficiency in vte5-2 plants can be complemented by overexpression of FOLK, indicating that FOLK is an authentic gene of tocopherol synthesis. The vte5-2 folk plants contain only ∼40% of wild-type amounts of phylloquinone, demonstrating that VTE5 and FOLK both contribute in part to phylloquinone synthesis. Tocotrienol and menaquinone-4 were produced in vte5-2 folk plants after supplementation with homogentisate or 1,4-dihydroxy-2-naphthoic acid, respectively, indicating that their synthesis is independent of the VTE5/FOLK pathway. These results show that phytyl moieties for tocopherol synthesis are completely but, for phylloquinone production, only partially derived from geranylgeranyl-chlorophyll and phytol phosphorylation by VTE5 and FOLK.


Assuntos
Arabidopsis , Fosfotransferases (Aceptor do Grupo Álcool) , Tocoferóis , Tocoferóis/metabolismo , Vitamina E/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Vitamina K 1/metabolismo , Fitol/metabolismo , Farneseno Álcool/metabolismo , Plantas/metabolismo , Cloroplastos/genética , Cloroplastos/metabolismo , Clorofila/metabolismo
9.
Nutrients ; 15(21)2023 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-37960177

RESUMO

Nutritional support is essential for patients with severe motor and intellectual disabilities (SMID) to ensure the smooth provision of medical care. These patients often require long-term tube feeding with enteral formulas, potentially leading to deficiencies in vitamins and trace elements. Additionally, frequent antibiotic use for infections often disrupts gut microbiota, inhibiting vitamin K2 production by intestinal bacteria. We assessed the serum protein induced by vitamin K absence or antagonists-II (PIVKA-II) and undercarboxylated osteocalcin (ucOC) levels to assess the vitamin K status in 20 patients with SMID (median age: 44.1 years, 11 men and 9 women) undergoing long-term tube feeding for durations ranging from 3 to 31 years. Thirteen (65%) and nine (45%) patients had elevated PIVKA-II (<40 mAU/mL) and serum ucOC levels (reference value < 4.50 ng/mL), respectively. Dietary vitamin K1 intake did not differ between patients with and without elevated PIVKA-II levels. Vitamin K2 supplementation for 3 months decreased serum PIVKA-II levels near those within the reference range. Approximately half of the patients with SMID on tube feeding had subclinical vitamin K deficiency. Further studies are needed to ascertain if long-term vitamin K2 supplementation effectively prevents vitamin K deficiency-induced hypercoagulation, osteoporosis, and vascular calcification in patients with SMID.


Assuntos
Deficiência Intelectual , Deficiência de Vitamina K , Masculino , Humanos , Feminino , Adulto , Vitamina K 2 , Nutrição Enteral , Protrombina/metabolismo , Biomarcadores , Vitamina K , Osteocalcina , Suplementos Nutricionais , Vitamina K 1
10.
Arch Osteoporos ; 18(1): 83, 2023 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-37338608

RESUMO

This study assessed whether vitamin K, given with oral bisphosphonate, calcium and/or vitamin D has an additive effect on fracture risk in post-menopausal women with osteoporosis. No difference in bone density or bone turnover was observed although vitamin K1 supplementation led to a modest effect on parameters of hip geometry. PURPOSE: Some clinical studies have suggested that vitamin K prevents bone loss and may improve fracture risk. The aim was to assess whether vitamin K supplementation has an additive effect on bone mineral density (BMD), hip geometry and bone turnover markers (BTMs) in post-menopausal women with osteoporosis (PMO) and sub-optimum vitamin K status receiving bisphosphonate, calcium and/or vitamin D treatment. METHODS: We conducted a trial in 105 women aged 68.7[12.3] years with PMO and serum vitamin K1 ≤ 0.4 µg/L. They were randomised to 3 treatment arms; vitamin K1 (1 mg/day) arm, vitamin K2 arm (MK-4; 45 mg/day) or placebo for 18 months. They were on oral bisphosphonate and calcium and/or vitamin D. We measured BMD by DXA, hip geometry parameters using hip structural analysis (HSA) software and BTMs. Vitamin K1 or MK-4 supplementation was each compared to placebo. Intention to treat (ITT) and per protocol (PP) analyses were performed. RESULTS: Changes in BMD at the total hip, femoral neck and lumbar spine and BTMs; CTX and P1NP did not differ significantly following either K1 or MK-4 supplementation compared to placebo. Following PP analysis and correction for covariates, there were significant differences in some of the HSA parameters at the intertrochanter (IT) and femoral shaft (FS): IT endocortical diameter (ED) (% change placebo:1.5 [4.1], K1 arm: -1.02 [5.07], p = 0.04), FS subperiosteal/outer diameter (OD) (placebo: 1.78 [5.3], K1 arm: 0.46 [2.23] p = 0.04), FS cross sectional area (CSA) (placebo:1.47 [4.09],K1 arm: -1.02[5.07], p = 0.03). CONCLUSION: The addition of vitamin K1 to oral bisphosphonate with calcium and/or vitamin D treatment in PMO has a modest effect on parameters of hip geometry. Further confirmatory studies are needed. TRIAL REGISTRATION: The study was registered at Clinicaltrial.gov:NCT01232647.


Assuntos
Fraturas Ósseas , Osteoporose Pós-Menopausa , Feminino , Humanos , Osteoporose Pós-Menopausa/tratamento farmacológico , Osteoporose Pós-Menopausa/prevenção & controle , Vitamina K/farmacologia , Vitamina K/uso terapêutico , Difosfonatos/uso terapêutico , Cálcio/uso terapêutico , Fraturas Ósseas/prevenção & controle , Fraturas Ósseas/tratamento farmacológico , Densidade Óssea , Vitaminas/uso terapêutico , Vitamina D/uso terapêutico , Vitamina K 1/farmacologia , Vitamina K 1/uso terapêutico , Colo do Fêmur , Cálcio da Dieta/uso terapêutico , Suplementos Nutricionais
11.
Clin Toxicol (Phila) ; 61(6): 429-435, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37293741

RESUMO

INTRODUCTION: Adulteration of illicit drugs is a well-known phenomenon that may expose consumers to unexpected adverse effects. We report a large outbreak of severe coagulopathy in northern Israel during nine months in 2021-2022 among users of synthetic cannabinoids adulterated with a long-acting anticoagulant, brodifacoum. METHODS: We performed a retrospective cohort study based on data extracted from the Israeli National Poison Information Center database and from electronic medical patient records at three participating hospitals. Confiscated drug samples and blood samples obtained at admission in a subgroup of patients were tested for the presence of long-acting anticoagulants. RESULTS: We identified 98 patients affected by the outbreak. All patients had a prolonged international normalized ratio on admission, and in 69%, the blood was non-coagulating. For patients treated in the three participating centers (n = 72), the presenting complaint was overt bleeding in 79% of patients, most commonly in the urinary (53%) and gastrointestinal tracts (50%). The most severe complications were intracranial bleeding (4%), hemothorax (3%), pericardial bleeding (1%), and four patients died. Brodifacoum was detected in all available blood samples (median concentration 207 µg/L, interquartile range 112-349 µg/L, range 45-1,118 µg/L), and the drug samples contained both brodifacoum and the synthetic cannabinoid ADB-BUTINACA. All patients were treated with high-dose phytomenadione (vitamin K1) and additionally by packed red blood cell transfusions, fresh frozen plasma, and/or 4-factor prothrombin complex concentrate when indicated. The most frequent phytomenadione (vitamin K1) dose regimen was initially 20 mg intravenously every eight hours, and at discharge, 20 mg orally three times daily. CONCLUSIONS: Outbreaks of severe coagulopathies in users of synthetic cannabinoids adulterated with a long-acting anticoagulant continue to erupt in different regions of the world. Rapid recognition of an outbreak requires a high index of suspicion when confronting young, otherwise healthy subjects with otherwise unexplained severe coagulopathy.


Assuntos
Transtornos da Coagulação Sanguínea , Canabinoides , Rodenticidas , Humanos , Vitamina K 1 , Israel/epidemiologia , Estudos Retrospectivos , Transtornos da Coagulação Sanguínea/induzido quimicamente , Transtornos da Coagulação Sanguínea/epidemiologia , Transtornos da Coagulação Sanguínea/tratamento farmacológico , Anticoagulantes/efeitos adversos , Hemorragia/induzido quimicamente , Hemorragia/epidemiologia , Hemorragia/tratamento farmacológico , Canabinoides/efeitos adversos , Surtos de Doenças
12.
Ann Pharmacother ; 57(10): 1178-1184, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-36803019

RESUMO

BACKGROUND: Essential to the coagulation pathway, vitamin K (phytonadione) is used to correct clotting factor deficiencies and for reversal of warfarin-induced bleeding. In practice, high-dose intravenous (IV) vitamin K is often used, despite limited evidence supporting repeated dosing. OBJECTIVE: This study sought to characterize differences in responders and nonresponders to high-dose vitamin K to guide dosing strategies. METHODS: This was a case-control study of hospitalized adults who received vitamin K 10 mg IV daily for 3 days. Cases were represented by patients who responded to the first dose of IV vitamin K and controls were nonresponders. The primary outcome was change in international normalized ratio (INR) over time with subsequent vitamin K doses. Secondary outcomes included factors associated with response to vitamin K and incidence of safety events. The Cleveland Clinic Institutional Review Board approved this study. RESULTS: There were 497 patients included, and 182 were responders. Most patients had underlying cirrhosis (91.5%). In responders, the INR decreased from 1.89 at baseline (95% CI = [1.74-2.04]) to 1.40 on day 3 (95% CI = [1.30-1.50]). In nonresponders, the INR decreased from 1.97 (95% CI = [1.83-2.13]) to 1.85 ([1.72-1.99]). Factors associated with response included lower body weight, absence of cirrhosis, and lower bilirubin. There was a low incidence of safety events observed. CONCLUSIONS: In this study of mainly patients with cirrhosis, the overall adjusted decrease in INR over 3 days was 0.3, which may have minimal clinical impact. Additional studies are needed to identify populations who may benefit from repeated daily doses of high-dose IV vitamin K.


Assuntos
Vitamina K , Varfarina , Adulto , Humanos , Estudos de Casos e Controles , Varfarina/uso terapêutico , Vitamina K 1/uso terapêutico , Vitamina K 1/farmacologia , Coagulação Sanguínea , Coeficiente Internacional Normatizado , Cirrose Hepática/tratamento farmacológico , Anticoagulantes/efeitos adversos
13.
J Nutr Health Aging ; 27(1): 38-45, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36651485

RESUMO

BACKGROUND: In recent years, a potential beneficial role of Vitamin K in neuromuscular function has been recognised. However, the optimal dietary intake of Vitamin K to support muscle function in the context of falls prevention remains unknown. OBJECTIVE: To examine the relationship of dietary Vitamin K1 and K2 with muscle function and long-term injurious fall-related hospitalisations in older women. DESIGN: Cohort study. PARTICIPANTS: 1347 community-dwelling older Australian women ≥70 years. MEASUREMENTS: A new Australian Vitamin K nutrient database, supplemented with published data, was used to calculate Vitamin K1 and K2 intake from a validated food frequency questionnaire at baseline (1998). Muscle function (grip strength and timed-up-and-go; TUG) as well plasma Vitamin D status (25OHD) were also assessed at baseline. Fall-related hospitalisations over 14.5 years were obtained from linked health records. Multivariable-adjusted logistic regression and Cox-proportional hazard models were used to analyse the data. RESULTS: Over 14.5 years of follow-up (14,774 person-years), 535 (39.7%) women experienced a fall-related hospitalisation. Compared to women with the lowest Vitamin K1 intake (Quartile 1, median 49 µg/d), those with the highest intake (Quartile 4, median 120 µg/d) had 29% lower odds (OR 0.71 95%CI 0.52-0.97) for slow TUG performance (>10.2 s), and 26% lower relative hazards of a fall-related hospitalisation (HR 0.74 95%CI 0.59-0.93) after multivariable adjustment. These associations were non-linear and plateaued at moderate intakes of ~70-100 µg/d. There was no relation to grip strength. Vitamin K2 intakes were not associated with muscle function or falls. CONCLUSION: A higher habitual Vitamin K1 intake was associated with better physical function and lower long-term injurious falls risk in community-dwelling older women. In the context of musculoskeletal health, Vitamin K1 found abundantly in green leafy vegetables should be promoted.


Assuntos
Vida Independente , Vitamina K 1 , Humanos , Feminino , Idoso , Masculino , Estudos de Coortes , Austrália , Vitamina K
14.
J Diet Suppl ; 20(4): 543-549, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35014576

RESUMO

Vitamin K acts a cofactor for the gamma-carboxylation of several proteins in the coagulation cascade. The clinical spectrum of vitamin K deficiency (VKD) can be asymptomatic to a significant bleeding. VKD is classically seen in newborns. However, this can manifest later in patients with risks such as sub-optimal nutrition, fat malabsorption, medications including antibiotics. A 17-year-old male with spinal muscular atrophy (SMA) Type 1, tracheostomy with ventilator dependent, gastrostomy tube feeding was seen by the gastroenterologist following treatment for small intestinal bacterial overgrowth (SIBO). Investigations showed coagulopathy following which he was transferred to the Pediatric ICU. Labs revealed prothrombin time (PT) 114 s [Normal 9.4-12.5 s], INR (International normalized ratio) 12.6 [Normal < 1.1] and partial thromboplastin time (PTT) 90 s [Normal 25.1-36.5 s]. Mixing studies and coagulation assays were consistent with VKD (low Factor VII and Factor IX with normal Factor V). His home blenderized feeding regimen met the caloric requirement but not the adequate intake (AI) values for vitamin K and other minerals. He received intravenous vitamin K (phytonadione) for five consecutive days with resolution of the coagulopathy (PT 13.2 s, PTT 37.1 s, INR 1.2). The patient was discharged on enteral vitamin K and additional supplements following dietary review by a nutritionist. Clinicians should be cognizant of VKD in patients on blenderized tube feeds which may not meet the adequate intake (AI) goals. In patients who are not receiving nutritionally complete formulas or receiving inadequate volumes, it is important to monitor macro and micronutrients.


Assuntos
Nutrição Enteral , Deficiência de Vitamina K , Masculino , Criança , Humanos , Recém-Nascido , Adolescente , Deficiência de Vitamina K/tratamento farmacológico , Vitamina K/metabolismo , Vitamina K/uso terapêutico , Vitamina K 1/uso terapêutico , Suplementos Nutricionais
15.
J Pediatr ; 255: 98-104, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36343740

RESUMO

OBJECTIVE: To study the efficacy of 3 different vitamin K birth prophylaxis regimens in infants born premature. STUDY DESIGN: This was an open-label, parallel-group, randomized clinical trial conducted in a tertiary neonatal care unit in India. Infants born very preterm (≤32 weeks) and/or with very low birth weight (≤1500 g) were included. In each arm, 25 babies were enrolled. Babies were randomized to receive 1.0 mg, 0.5 mg, or 0.3 mg intramuscular (IM) vitamin K1 at birth. Protein induced by vitamin K absence - II (PIVKA-II) levels were assessed at birth, and on days 5 and 28, along with the frequency of death, bleeding manifestations, intraventricular hemorrhage, necrotizing enterocolitis, bilirubin levels, and duration of phototherapy. The primary outcome was comparison of PIVKA-II levels on day 5 of life. RESULTS: All the 3 regimens resulted in similar proportion of vitamin K subclinical sufficiency (PIVKA-II < 0.028 AU/mL) infants on day 5 (1 mg - 100%; 0.5 mg - 91.7%; 0.3 mg - 91.7%, P = .347), with no significant difference in median (IQR) PIVKA-II levels (AU/mL): 1 mg 0.006 (0.004, 0.009); 0.5 mg 0.008 (0.004, 0.009); 0.3 mg 0.006 (0.003, 0.009), P = .301. However, on day 28, there was a significant decrease in the proportion of vitamin K-sufficient infants in the 0.3-mg IM group (72.7%) compared with the 1.0-mg (100%) or 0.5-mg (91.3) groups. The 1.0-mg group had significantly greater bilirubin levels and duration of phototherapy. None of the other clinical outcomes were statistically different. CONCLUSIONS: Both 1-mg and 0.5-mg IM vitamin K birth prophylaxis resulted in high sufficiency on follow-up, compared with 0.3 mg. The current recommendation of 0.5-1 mg IM vitamin K birth prophylaxis for infants born preterm, needs to be continued. TRIAL REGISTRATION: CTRI/2022/02/040396.


Assuntos
Protrombina , Vitamina K , Recém-Nascido , Lactente , Humanos , Precursores de Proteínas/metabolismo , Vitamina K 1/uso terapêutico , Vitaminas , Bilirrubina
16.
BMC Pediatr ; 22(1): 663, 2022 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-36384469

RESUMO

BACKGROUND: The incidence of early-onset vitamin K deficiency bleeding (VKDB) in at-risk neonates who did not receive vitamin K supplementation varied from 6 to 12%. This case report aims to show that VKDB can occur abruptly after birth despite vitamin K1 1 mg IM being given immediately after birth. CASE PRESENTATION: A term female baby was born through vaginal delivery of a 28 years old mother, G1P0A0, 39-40 weeks gestation with normal APGAR score, and birth weight was 3445 g, birth length was 52 cm. During pregnancy, the mother did not take any drugs except vitamins. There are no abnormalities on the baby's physical examination. The anus is patent. Immediately after birth, the baby received a vitamin K1 1 mg intramuscularly. Abruptly, 50 min after delivery, there was meconium with lots of fresh blood. Laboratory results showed hemoglobin, 19.6 g/dL; leukocytes, 25,010/uL; platelets, 390,000/uL, with increased PT and aPTT. A peripheral blood smear showed a normal blood morphology. When 7 h old, the baby had much hematochezia. Laboratory results showed decreased hemoglobin to 17.5 g/dL and increased PT, aPTT, and INR. No abnormalities were found on the babygram and abdominal ultrasound. The working diagnosis was gastrointestinal bleeding due to idiopathic early-onset VKDB. The baby received vitamin K1 2 mg IM, Fresh Frozen Plasma, and a Packed Red Cells transfusion. The patient returned home in good clinical condition. CONCLUSION: Vitamin K1 1 mg IM prophylaxis should be given immediately after birth to prevent early-onset VKDB. In addition, pregnant women who receive drugs that interfere with vitamin K metabolism (anti-epileptic drugs, anti-tuberculosis drugs, vitamin K antagonist drugs) should be given prophylactic vitamin K1, 20 mg/d orally, for at least two weeks before the expected time of delivery.


Assuntos
Sangramento por Deficiência de Vitamina K , Lactente , Recém-Nascido , Feminino , Humanos , Gravidez , Adulto , Sangramento por Deficiência de Vitamina K/complicações , Sangramento por Deficiência de Vitamina K/diagnóstico , Vitamina K 1 , Vitamina K/uso terapêutico , Vitaminas , Hemorragia Gastrointestinal/etiologia
17.
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
18.
Nutrients ; 14(20)2022 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-36296903

RESUMO

Vitamin K is the common name for a group of compounds recognized as essential for blood clotting. The group comprises phylloquinone (K1)-a 2-methyl-3-phytyl-1,4-naphthoquinone; menaquinone (K2, MK)-a group of compounds with an unsaturated side chain in position 3 of a different number of isoprene units and a 1,4-naphthoquinone group and menadione (K3, MD)-a group of synthetic, water-soluble compounds 2-methyl-1,4-naphthoquinone. However, recent epidemiological studies suggest that vitamin K has various benefits that go beyond blood coagulation processes. A dietary intake of K1 is inversely associated with the risk of pancreatic cancer, K2 has the potential to induce a differentiation in leukemia cells or apoptosis of various types of cancer cells, and K3 has a documented anti-cancer effect. A healthy diet rich in fruit and vegetables ensures an optimal supply of K1 and K2, though consumers often prefer supplements. Interestingly, the synthetic form of vitamin K-menadione-appears in the cell during the metabolism of phylloquinone and is a precursor of MK-4, a form of vitamin K2 inaccessible in food. With this in mind, the purpose of this review is to emphasize the importance of vitamin K as a micronutrient, which not only has a beneficial effect on blood clotting and the skeleton, but also reduces the risk of cancer and other pro-inflammatory diseases. A proper diet should be a basic and common preventive procedure, resulting in a healthier society and reduced burden on healthcare systems.


Assuntos
Vitamina K 1 , Vitamina K , Humanos , Vitamina K/farmacologia , Vitamina K 1/metabolismo , Vitamina K 2/metabolismo , Vitamina K 3/metabolismo , Dano ao DNA , Micronutrientes , Água
19.
Food Funct ; 13(20): 10642-10650, 2022 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-36169025

RESUMO

This study examined the association between dietary Vitamin K1 intake with fracture-related hospitalizations over 14.5 years in community-dwelling older Australian women (n = 1373, ≥70 years). Dietary Vitamin K1 intake at baseline (1998) was estimated using a validated food frequency questionnaire and a new Australian Vitamin K nutrient database, which was supplemented with published data. Over 14.5 years, any fracture (n = 404, 28.3%) and hip fracture (n = 153, 10.7%) related hospitalizations were captured using linked health data. Plasma Vitamin D status (25OHD) and the ratio of undercarboxylated osteocalcin (ucOC) to total osteocalcin (tOC) from serum was assessed at baseline. Estimates of dietary Vitamin K1 intake were supported by a significant inverse association with ucOC : tOC; a marker of Vitamin K status (r = -0.12, p < 0.001). Compared to women with the lowest Vitamin K1 intake (Quartile 1, <61 µg d-1), women with the highest Vitamin K1 intake (Quartile 4, ≥99 µg d-1) had lower hazards for any fracture- (HR 0.69 95%CI 0.52-0.91, p < 0.001) and hip fracture-related hospitalization (HR 0.51 95%CI 0.32-0.79, p < 0.001), independent of 25OHD levels, as part of multivariable-adjusted analysis. Spline analysis suggested a nadir in the relative hazard for any fracture-related hospitalizations at a Vitamin K1 intake of approximately 100 µg day-1. For hip fractures, a similar relationship was apparent. Higher dietary Vitamin K1 is associated with lower long-term risk for any fracture- and hip fracture-related hospitalizations in community-dwelling older women.


Assuntos
Fraturas do Quadril , Vitamina K 1 , Idoso , Envelhecimento , Austrália , Feminino , Fraturas do Quadril/epidemiologia , Hospitalização , Humanos , Estudos Longitudinais , Osteocalcina , Fatores de Risco , Vitamina D , Vitamina K , Vitamina K 2
20.
J Thromb Haemost ; 20(12): 2773-2785, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36087073

RESUMO

BACKGROUND: There is near-global consensus that all newborns be given parenteral vitamin K1 (VK1 ) at birth as prophylaxis against VK deficiency bleeding (VKDB). Breastmilk has a low VK content and cases of late VKDB are reported in exclusively breastmilk-fed preterm infants despite VK prophylaxis at birth. OBJECTIVES: To assess the prevalence of functional VK insufficiency in preterm infants based on elevated under-γ-carboxylated (Glu) species of Gla proteins, factor II (PIVKA-II), and osteocalcin (GluOC), synthesized by liver and bone, respectively. PATIENTS/METHODS: Prospective, multicenter, observational study in preterm infants born <33 weeks' gestation. Blood samples and dietary history were collected before hospital discharge, and after discharge at 2-3 months' corrected age. Outcome measures were serum VK1 , PIVKA-II, and %GluOC (GluOC as a percentage of the sum of GluOC plus GlaOC) compared between exclusively breastmilk-fed and formula/mixed-fed infants after discharge. RESULTS: After discharge, breastmilk-fed babies had significantly lower serum VK1 (0.15 vs. 1.81 µg/L), higher PIVKA-II (0.10 vs. 0.02 AU/ml) and higher %GluOC (63.6% vs. 8.1%) than those receiving a formula/mixed-feed diet. Pre-discharge (based on elevated PIVKA-II), only one (2%) of 45 breastmilk-fed infants was VK insufficient. After discharge, eight (67%) of 12 exclusively breastmilk-fed babies were VK insufficient versus only one (4%) of 25 formula/mixed-fed babies. CONCLUSIONS: Preterm infants who remain exclusively or predominantly human breastmilk-fed after neonatal unit discharge are at high risk of developing subclinical VK deficiency in early infancy. Routine postdischarge VK1 supplementation of breastfed infants to provide intakes comparable to those from formula milks should prevent this deficiency.


Assuntos
Leite Humano , Deficiência de Vitamina K , Lactente , Recém-Nascido , Humanos , Recém-Nascido Prematuro , Assistência ao Convalescente , Estudos Prospectivos , Alta do Paciente , Deficiência de Vitamina K/diagnóstico , Deficiência de Vitamina K/epidemiologia , Deficiência de Vitamina K/prevenção & controle , Vitamina K 1 , Hemorragia , Vitamina K
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