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1.
N Engl J Med ; 391(1): 32-43, 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38819658

RESUMO

BACKGROUND: Approved on-demand treatments for hereditary angioedema attacks need to be administered parenterally, a route of administration that is associated with delays in treatment or withholding of therapy. METHODS: In this phase 3, double-blind, three-way crossover trial, we randomly assigned participants at least 12 years of age with type 1 or type 2 hereditary angioedema to take up to two oral doses of sebetralstat (300 mg or 600 mg) or placebo for an angioedema attack. The primary end point, assessed in a time-to-event analysis, was the beginning of symptom relief, defined as a rating of "a little better" on the Patient Global Impression of Change scale (ratings range from "much worse" to "much better") at two or more consecutive time points within 12 hours after the first administration of the trial agent. Key secondary end points, assessed in a time-to-event analysis, were a reduction in attack severity (an improved rating on the Patient Global Impression of Severity [PGI-S] scale, with ratings ranging from "none" to "very severe") at two or more consecutive time points within 12 hours and complete attack resolution (a rating of "none" on the PGI-S scale) within 24 hours. RESULTS: A total of 136 participants were assigned to one of six trial sequences, with 110 treating 264 attacks. The time to the beginning of symptom relief with the 300-mg dose and the 600-mg dose was faster than with placebo (P<0.001 and P = 0.001 for the two comparisons, respectively), with median times of 1.61 hours (interquartile range, 0.78 to 7.04), 1.79 hours (1.02 to 3.79), and 6.72 hours (1.34 to >12), respectively. The time to reduction in the attack severity with the 300-mg dose and the 600-mg dose was faster than with placebo (P = 0.004 and P = 0.003), with median times of 9.27 hours (interquartile range, 1.53 to >12), 7.75 hours (2.19 to >12), and more than 12 hours (6.23 to >12). The time to complete resolution was faster with the 300-mg and 600-mg doses than with placebo (P = 0.002 and P<0.001). The percentage of attacks with complete resolution within 24 hours was 42.5% with the 300-mg dose, 49.5% with the 600-mg dose, and 27.4% with placebo. Sebetralstat and placebo had similar safety profiles; no serious adverse events related to the trial agents were reported. CONCLUSIONS: Oral sebetralstat provided faster times to the beginning of symptom relief, reduction in attack severity, and complete attack resolution than placebo. (Funded by KalVista Pharmaceuticals; KONFIDENT ClinicalTrials.gov number, NCT05259917; EudraCT number, 2021-001226-21.).


Assuntos
Estudos Cross-Over , Humanos , Feminino , Método Duplo-Cego , Masculino , Adulto , Administração Oral , Pessoa de Meia-Idade , Angioedemas Hereditários/tratamento farmacológico , Adolescente , Adulto Jovem , Idoso , Angioedema Hereditário Tipos I e II/tratamento farmacológico , Pirazóis
2.
N Engl J Med ; 390(17): 1584-1596, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38692292

RESUMO

BACKGROUND: Congenital thrombotic thrombocytopenic purpura (TTP) results from severe hereditary deficiency of ADAMTS13. The efficacy and safety of recombinant ADAMTS13 and standard therapy (plasma-derived products) administered as routine prophylaxis or on-demand treatment in patients with congenital TTP is not known. METHODS: In this phase 3, open-label, crossover trial, we randomly assigned patients in a 1:1 ratio to two 6-month periods of prophylaxis with recombinant ADAMTS13 (40 IU per kilogram of body weight, administered intravenously) or standard therapy, followed by the alternate treatment; thereafter, all the patients received recombinant ADAMTS13 for an additional 6 months. The trigger for this interim analysis was trial completion by at least 30 patients. The primary outcome was acute TTP events. Manifestations of TTP, safety, and pharmacokinetics were assessed. Patients who had an acute TTP event could receive on-demand treatment. RESULTS: A total of 48 patients underwent randomization; 32 completed the trial. No acute TTP event occurred during prophylaxis with recombinant ADAMTS13, whereas 1 patient had an acute TTP event during prophylaxis with standard therapy (mean annualized event rate, 0.05). Thrombocytopenia was the most frequent TTP manifestation (annualized event rate, 0.74 with recombinant ADAMTS13 and 1.73 with standard therapy). Adverse events occurred in 71% of the patients with recombinant ADAMTS13 and in 84% with standard therapy. Adverse events that were considered by investigators to be related to the trial drug occurred in 9% of the patients with recombinant ADAMTS13 and in 48% with standard therapy. Trial-drug interruption or discontinuation due to adverse events occurred in no patients with recombinant ADAMTS13 and in 8 patients with standard therapy. No neutralizing antibodies developed during recombinant ADAMTS13 treatment. The mean maximum ADAMTS13 activity after recombinant ADAMTS13 treatment was 101%, as compared with 19% after standard therapy. CONCLUSIONS: During prophylaxis with recombinant ADAMTS13 in patients with congenital TTP, ADAMTS13 activity reached approximately 100% of normal levels, adverse events were generally mild or moderate in severity, and TTP events and manifestations were rare. (Funded by Takeda Development Center Americas and Baxalta Innovations; ClinicalTrials.gov number, NCT03393975.).


Assuntos
Proteína ADAMTS13 , Púrpura Trombocitopênica Trombótica , Proteínas Recombinantes , Adolescente , Adulto , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem , Proteína ADAMTS13/administração & dosagem , Proteína ADAMTS13/efeitos adversos , Proteína ADAMTS13/deficiência , Proteína ADAMTS13/genética , Estudos Cross-Over , Púrpura Trombocitopênica Trombótica/congênito , Púrpura Trombocitopênica Trombótica/tratamento farmacológico , Púrpura Trombocitopênica Trombótica/genética , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/efeitos adversos , Pré-Escolar
3.
N Engl J Med ; 390(5): 421-431, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38294974

RESUMO

BACKGROUND: Niemann-Pick disease type C is a rare lysosomal storage disorder. We evaluated the safety and efficacy of N-acetyl-l-leucine (NALL), an agent that potentially ameliorates lysosomal and metabolic dysfunction, for the treatment of Niemann-Pick disease type C. METHODS: In this double-blind, placebo-controlled, crossover trial, we randomly assigned patients 4 years of age or older with genetically confirmed Niemann-Pick disease type C in a 1:1 ratio to receive NALL for 12 weeks, followed by placebo for 12 weeks, or to receive placebo for 12 weeks, followed by NALL for 12 weeks. NALL or matching placebo was administered orally two to three times per day, with patients 4 to 12 years of age receiving weight-based doses (2 to 4 g per day) and those 13 years of age or older receiving a dose of 4 g per day. The primary end point was the total score on the Scale for the Assessment and Rating of Ataxia (SARA; range, 0 to 40, with lower scores indicating better neurologic status). Secondary end points included scores on the Clinical Global Impression of Improvement, the Spinocerebellar Ataxia Functional Index, and the Modified Disability Rating Scale. Crossover data from the two 12-week periods in each group were included in the comparisons of NALL with placebo. RESULTS: A total of 60 patients 5 to 67 years of age were enrolled. The mean baseline SARA total scores used in the primary analysis were 15.88 before receipt of the first dose of NALL (60 patients) and 15.68 before receipt of the first dose of placebo (59 patients; 1 patient never received placebo). The mean (±SD) change from baseline in the SARA total score was -1.97±2.43 points after 12 weeks of receiving NALL and -0.60±2.39 points after 12 weeks of receiving placebo (least-squares mean difference, -1.28 points; 95% confidence interval, -1.91 to -0.65; P<0.001). The results for the secondary end points were generally supportive of the findings in the primary analysis, but these were not adjusted for multiple comparisons. The incidence of adverse events was similar with NALL and placebo, and no treatment-related serious adverse events occurred. CONCLUSIONS: Among patients with Niemann-Pick disease type C, treatment with NALL for 12 weeks led to better neurologic status than placebo. A longer period is needed to determine the long-term effects of this agent in patients with Niemann-Pick disease type C. (Funded by IntraBio; ClinicalTrials.gov number, NCT05163288; EudraCT number, 2021-005356-10.).


Assuntos
Fármacos do Sistema Nervoso Central , Doença de Niemann-Pick Tipo C , Humanos , Coleta de Dados , Método Duplo-Cego , Leucina/análogos & derivados , Leucina/uso terapêutico , Doença de Niemann-Pick Tipo C/complicações , Doença de Niemann-Pick Tipo C/diagnóstico , Doença de Niemann-Pick Tipo C/tratamento farmacológico , Doença de Niemann-Pick Tipo C/genética , Resultado do Tratamento , Estudos Cross-Over , Pré-Escolar , Criança , Adolescente , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Idoso , Fármacos do Sistema Nervoso Central/administração & dosagem , Fármacos do Sistema Nervoso Central/uso terapêutico
4.
N Engl J Med ; 390(5): 409-420, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38294973

RESUMO

BACKGROUND: Studies evaluating surgical-site infection have had conflicting results with respect to the use of alcohol solutions containing iodine povacrylex or chlorhexidine gluconate as skin antisepsis before surgery to repair a fractured limb (i.e., an extremity fracture). METHODS: In a cluster-randomized, crossover trial at 25 hospitals in the United States and Canada, we randomly assigned hospitals to use a solution of 0.7% iodine povacrylex in 74% isopropyl alcohol (iodine group) or 2% chlorhexidine gluconate in 70% isopropyl alcohol (chlorhexidine group) as preoperative antisepsis for surgical procedures to repair extremity fractures. Every 2 months, the hospitals alternated interventions. Separate populations of patients with either open or closed fractures were enrolled and included in the analysis. The primary outcome was surgical-site infection, which included superficial incisional infection within 30 days or deep incisional or organ-space infection within 90 days. The secondary outcome was unplanned reoperation for fracture-healing complications. RESULTS: A total of 6785 patients with a closed fracture and 1700 patients with an open fracture were included in the trial. In the closed-fracture population, surgical-site infection occurred in 77 patients (2.4%) in the iodine group and in 108 patients (3.3%) in the chlorhexidine group (odds ratio, 0.74; 95% confidence interval [CI], 0.55 to 1.00; P = 0.049). In the open-fracture population, surgical-site infection occurred in 54 patients (6.5%) in the iodine group and in 60 patients (7.3%) in the chlorhexidine group (odd ratio, 0.86; 95% CI, 0.58 to 1.27; P = 0.45). The frequencies of unplanned reoperation, 1-year outcomes, and serious adverse events were similar in the two groups. CONCLUSIONS: Among patients with closed extremity fractures, skin antisepsis with iodine povacrylex in alcohol resulted in fewer surgical-site infections than antisepsis with chlorhexidine gluconate in alcohol. In patients with open fractures, the results were similar in the two groups. (Funded by the Patient-Centered Outcomes Research Institute and the Canadian Institutes of Health Research; PREPARE ClinicalTrials.gov number, NCT03523962.).


Assuntos
Anti-Infecciosos Locais , Clorexidina , Fixação de Fratura , Fraturas Ósseas , Iodo , Infecção da Ferida Cirúrgica , Humanos , 2-Propanol/administração & dosagem , 2-Propanol/efeitos adversos , 2-Propanol/uso terapêutico , Anti-Infecciosos Locais/administração & dosagem , Anti-Infecciosos Locais/efeitos adversos , Anti-Infecciosos Locais/uso terapêutico , Antissepsia/métodos , Canadá , Clorexidina/administração & dosagem , Clorexidina/efeitos adversos , Clorexidina/uso terapêutico , Etanol , Extremidades/lesões , Extremidades/microbiologia , Extremidades/cirurgia , Iodo/administração & dosagem , Iodo/efeitos adversos , Iodo/uso terapêutico , Cuidados Pré-Operatórios/efeitos adversos , Cuidados Pré-Operatórios/métodos , Pele/microbiologia , Infecção da Ferida Cirúrgica/etiologia , Infecção da Ferida Cirúrgica/prevenção & controle , Fraturas Ósseas/cirurgia , Estudos Cross-Over , Estados Unidos
5.
N Engl J Med ; 388(12): 1092-1100, 2023 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-36947466

RESUMO

BACKGROUND: Coffee is one of the most commonly consumed beverages in the world, but the acute health effects of coffee consumption remain uncertain. METHODS: We conducted a prospective, randomized, case-crossover trial to examine the effects of caffeinated coffee on cardiac ectopy and arrhythmias, daily step counts, sleep minutes, and serum glucose levels. A total of 100 adults were fitted with a continuously recording electrocardiogram device, a wrist-worn accelerometer, and a continuous glucose monitor. Participants downloaded a smartphone application to collect geolocation data. We used daily text messages, sent over a period of 14 days, to randomly instruct participants to consume caffeinated coffee or avoid caffeine. The primary outcome was the mean number of daily premature atrial contractions. Adherence to the randomization assignment was assessed with the use of real-time indicators recorded by the participants, daily surveys, reimbursements for date-stamped receipts for coffee purchases, and virtual monitoring (geofencing) of coffee-shop visits. RESULTS: The mean (±SD) age of the participants was 39±13 years; 51% were women, and 51% were non-Hispanic White. Adherence to the random assignments was assessed to be high. The consumption of caffeinated coffee was associated with 58 daily premature atrial contractions as compared with 53 daily events on days when caffeine was avoided (rate ratio, 1.09; 95% confidence interval [CI], 0.98 to 1.20; P = 0.10). The consumption of caffeinated coffee as compared with no caffeine consumption was associated with 154 and 102 daily premature ventricular contractions, respectively (rate ratio, 1.51; 95% CI, 1.18 to 1.94); 10,646 and 9665 daily steps (mean difference, 1058; 95% CI, 441 to 1675); 397 and 432 minutes of nightly sleep (mean difference, 36; 95% CI, 25 to 47); and serum glucose levels of 95 mg per deciliter and 96 mg per deciliter (mean difference, -0.41; 95% CI, -5.42 to 4.60). CONCLUSIONS: In this randomized trial, the consumption of caffeinated coffee did not result in significantly more daily premature atrial contractions than the avoidance of caffeine. (Funded by the University of California, San Francisco, and the National Institutes of Health; CRAVE ClinicalTrials.gov number, NCT03671759.).


Assuntos
Complexos Atriais Prematuros , Glicemia , Cafeína , Café , Duração do Sono , Caminhada , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Complexos Atriais Prematuros/induzido quimicamente , Complexos Atriais Prematuros/etiologia , Cafeína/efeitos adversos , Cafeína/farmacologia , Café/efeitos adversos , Glucose , Estudos Prospectivos , Ingestão de Líquidos , Estudos Cross-Over , Glicemia/análise , Duração do Sono/efeitos dos fármacos , Acelerometria , Eletrocardiografia Ambulatorial , Automonitorização da Glicemia , Aplicativos Móveis , Envio de Mensagens de Texto , Complexos Ventriculares Prematuros/induzido quimicamente , Complexos Ventriculares Prematuros/etiologia
6.
Blood ; 143(20): 2073-2088, 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38427589

RESUMO

ABSTRACT: Platelets are stored at room temperature for 5 to 7 days (room temperature-stored platelets [RSPs]). Because of frequent and severe shortages, the US Food and Drug Administration recently approved up to 14-day cold-stored platelets (CSPs) in plasma. However, the posttransfusion function of CSPs is unknown and it is unclear which donors are best suited to provide either RSPs or CSPs. In this study, we sought to evaluate the posttransfusion platelet function and its predictors for platelets stored for the maximum approved storage times (7-day RSPs and 14-day CSPs) in healthy volunteers on acetylsalicylic acid (ASA). We conducted a randomized crossover study in 10 healthy humans. Individuals donated 1 platelet unit, stored at either 22°C or 4°C based on randomization. Before transfusion, participants ingested ASA to inhibit endogenous platelets. Transfusion recipients were tested for platelet function and lipid mediators. Platelet units were tested for lipid mediators only. A second round of transfusion with the alternative product was followed by an identical testing sequence. RSPs reversed platelet inhibition significantly better in αIIbß3 integrin activation-dependent assays. In contrast, CSPs in recipients led to significantly more thrombin generation, which was independent of platelet microparticles. Lysophosphatidylcholine-O species levels predicted the procoagulant capacity of CSPs. In contrast, polyunsaturated fatty acid concentrations predicted the aggregation response of RSPs. In summary, we provide, to our knowledge, the first efficacy data of extended-stored CSPs in plasma. Our results suggest that identifying ideal RSP and CSP donors is possible, and pave the way for larger studies in the future. This trial is registered at www.ClinicalTrials.gov as #NCT0511102.


Assuntos
Plaquetas , Preservação de Sangue , Estudos Cross-Over , Transfusão de Plaquetas , Humanos , Preservação de Sangue/métodos , Transfusão de Plaquetas/métodos , Masculino , Feminino , Adulto , Plaquetas/metabolismo , Temperatura Baixa , Temperatura , Testes de Função Plaquetária , Pessoa de Meia-Idade , Agregação Plaquetária , Aspirina
7.
Circ Res ; 135(2): 320-331, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38832504

RESUMO

BACKGROUND: Vascular cognitive impairment due to cerebral small vessel disease is associated with cerebral pulsatility, white matter hypoperfusion, and reduced cerebrovascular reactivity (CVR), and is potentially improved by endothelium-targeted drugs such as cilostazol. Whether sildenafil, a phosphodiesterase-5 inhibitor, improves cerebrovascular dysfunction is unknown. METHODS: OxHARP trial (Oxford Haemodynamic Adaptation to Reduce Pulsatility) was a double-blind, randomized, placebo-controlled, 3-way crossover trial after nonembolic cerebrovascular events with mild-moderate white matter hyperintensities (WMH), the most prevalent manifestation of cerebral small vessel disease. The primary outcome assessed the superiority of 3 weeks of sildenafil 50 mg thrice daily versus placebo (mixed-effect linear models) on middle cerebral artery pulsatility, derived from peak systolic and end-diastolic velocities (transcranial ultrasound), with noninferiority to cilostazol 100 mg twice daily. Secondary end points included the following: cerebrovascular reactivity during inhalation of air, 4% and 6% CO2 on transcranial ultrasound (transcranial ultrasound-CVR); blood oxygen-level dependent-magnetic resonance imaging within WMH (CVR-WMH) and normal-appearing white matter (CVR-normal-appearing white matter); cerebral perfusion by arterial spin labeling (magnetic resonance imaging pseudocontinuous arterial spin labeling); and resistance by cerebrovascular conductance. Adverse effects were compared by Cochran Q. RESULTS: In 65/75 (87%) patients (median, 70 years;79% male) with valid primary outcome data, cerebral pulsatility was unchanged on sildenafil versus placebo (0.02, -0.01 to 0.05; P=0.18), or versus cilostazol (-0.01, -0.04 to 0.02; P=0.36), despite increased blood flow (∆ peak systolic velocity, 6.3 cm/s, 3.5-9.07; P<0.001; ∆ end-diastolic velocity, 1.98, 0.66-3.29; P=0.004). Secondary outcomes improved on sildenafil versus placebo for CVR-transcranial ultrasound (0.83 cm/s per mm Hg, 0.23-1.42; P=0.007), CVR-WMH (0.07, 0-0.14; P=0.043), CVR-normal-appearing white matter (0.06, 0.00-0.12; P=0.048), perfusion (WMH: 1.82 mL/100 g per minute, 0.5-3.15; P=0.008; and normal-appearing white matter, 2.12, 0.66-3.6; P=0.006) and cerebrovascular resistance (sildenafil-placebo: 0.08, 0.05-0.10; P=4.9×10-8; cilostazol-placebo, 0.06, 0.03-0.09; P=5.1×10-5). Both drugs increased headaches (P=1.1×10-4), while cilostazol increased moderate-severe diarrhea (P=0.013). CONCLUSIONS: Sildenafil did not reduce pulsatility but increased cerebrovascular reactivity and perfusion. Sildenafil merits further study to determine whether it prevents the clinical sequelae of small vessel disease. REGISTRATION: URL: https://www.clinicaltrials.gov/study/NCT03855332; Unique identifier: NCT03855332.


Assuntos
Doenças de Pequenos Vasos Cerebrais , Circulação Cerebrovascular , Estudos Cross-Over , Citrato de Sildenafila , Humanos , Citrato de Sildenafila/uso terapêutico , Citrato de Sildenafila/farmacologia , Citrato de Sildenafila/efeitos adversos , Masculino , Feminino , Idoso , Método Duplo-Cego , Doenças de Pequenos Vasos Cerebrais/tratamento farmacológico , Doenças de Pequenos Vasos Cerebrais/fisiopatologia , Doenças de Pequenos Vasos Cerebrais/diagnóstico por imagem , Circulação Cerebrovascular/efeitos dos fármacos , Pessoa de Meia-Idade , Cilostazol/uso terapêutico , Cilostazol/farmacologia , Cilostazol/efeitos adversos , Inibidores da Fosfodiesterase 5/uso terapêutico , Inibidores da Fosfodiesterase 5/efeitos adversos , Inibidores da Fosfodiesterase 5/farmacologia , Resultado do Tratamento , Fluxo Pulsátil/efeitos dos fármacos , Imageamento por Ressonância Magnética , Artéria Cerebral Média/efeitos dos fármacos , Artéria Cerebral Média/diagnóstico por imagem , Artéria Cerebral Média/fisiopatologia
8.
Circulation ; 149(1): 36-47, 2024 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-37905403

RESUMO

BACKGROUND: Angina with nonobstructive coronary arteries is a common condition for which no effective treatment has been established. We hypothesized that the measurement of coronary flow reserve (CFR) allows identification of patients with angina with nonobstructive coronary arteries who would benefit from anti-ischemic therapy. METHODS: Patients with angina with nonobstructive coronary arteries underwent blinded invasive CFR measurement and were randomly assigned to receive 4 weeks of amlodipine or ranolazine. After a 1-week washout, they crossed over to the other drug for 4 weeks; final assessment was after the cessation of study medication for another 4 weeks. The primary outcome was change in treadmill exercise time, and the secondary outcome was change in Seattle Angina Questionnaire summary score in response to anti-ischemic therapy. Analysis was on a per protocol basis according to the following classification: coronary microvascular disease (CMD group) if CFR<2.5 and reference group if CFR≥2.5. The study protocol was registered before the first patient was enrolled (International Standard Randomised Controlled Trial Number: ISRCTN94728379). RESULTS: Eighty-seven patients (61±8 years of age; 62% women) underwent random assignment (57 CMD group and 30 reference group). Baseline exercise time and Seattle Angina Questionnaire summary scores were similar between groups. The CMD group had a greater increment (delta) in exercise time than the reference group in response to both amlodipine (difference in delta, 82 s [95% CI, 37-126 s]; P<0.001) and ranolazine (difference in delta, 68 s [95% CI, 21-115 s]; P=0.005). The CMD group reported a greater increment (delta) in Seattle Angina Questionnaire summary score than the reference group in response to ranolazine (difference in delta, 7 points [95% CI, 0-15]; P=0.048), but not to amlodipine (difference in delta, 2 points [95% CI, -5 to 8]; P=0.549). CONCLUSIONS: Among phenotypically similar patients with angina with nonobstructive coronary arteries, only those with an impaired CFR derive benefit from anti-ischemic therapy. These findings support measurement of CFR to diagnose and guide management of this otherwise heterogeneous patient group.


Assuntos
Doença da Artéria Coronariana , Angina Microvascular , Isquemia Miocárdica , Feminino , Humanos , Masculino , Anlodipino/uso terapêutico , Doença da Artéria Coronariana/tratamento farmacológico , Circulação Coronária , Estudos Cross-Over , Microcirculação , Fenótipo , Ranolazina/uso terapêutico , Pessoa de Meia-Idade , Idoso
9.
Circulation ; 149(19): 1474-1489, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38533643

RESUMO

BACKGROUND: Heart failure triggers a shift in myocardial metabolic substrate utilization, favoring the ketone body 3-hydroxybutyrate as energy source. We hypothesized that 14-day treatment with ketone ester (KE) would improve resting and exercise hemodynamics and exercise capacity in patients with heart failure with reduced ejection fraction. METHODS: In a randomized, double-blind cross-over study, nondiabetic patients with heart failure with reduced ejection fraction received 14-day KE and 14-day isocaloric non-KE comparator regimens of 4 daily doses separated by a 14-day washout period. After each treatment period, participants underwent right heart catheterization, echocardiography, and blood sampling at plasma trough levels and after dosing. Participants underwent an exercise hemodynamic assessment after a second dosing. The primary end point was resting cardiac output (CO). Secondary end points included resting and exercise pulmonary capillary wedge pressure and peak exercise CO and metabolic equivalents. RESULTS: We included 24 patients with heart failure with reduced ejection fraction (17 men; 65±9 years of age; all White). Resting CO at trough levels was higher after KE compared with isocaloric comparator (5.2±1.1 L/min versus 5.0±1.1 L/min; difference, 0.3 L/min [95% CI, 0.1-0.5), and pulmonary capillary wedge pressure was lower (8±3 mm Hg versus 11±3 mm Hg; difference, -2 mm Hg [95% CI, -4 to -1]). These changes were amplified after KE dosing. Across all exercise intensities, KE treatment was associated with lower mean exercise pulmonary capillary wedge pressure (-3 mm Hg [95% CI, -5 to -1] ) and higher mean CO (0.5 L/min [95% CI, 0.1-0.8]), significantly different at low to moderate steady-state exercise but not at peak. Metabolic equivalents remained similar between treatments. In exploratory analyses, KE treatment was associated with 18% lower NT-proBNP (N-terminal pro-B-type natriuretic peptide; difference, -98 ng/L [95% CI, -185 to -23]), higher left ventricular ejection fraction (37±5 versus 34±5%; P=0.01), and lower left atrial and ventricular volumes. CONCLUSIONS: KE treatment for 14 days was associated with higher CO at rest and lower filling pressures, cardiac volumes, and NT-proBNP levels compared with isocaloric comparator. These changes persisted during exercise and were achieved on top of optimal medical therapy. Sustained modulation of circulating ketone bodies is a potential treatment principle in patients with heart failure with reduced ejection fraction. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT05161650.


Assuntos
Insuficiência Cardíaca , Volume Sistólico , Humanos , Masculino , Insuficiência Cardíaca/tratamento farmacológico , Insuficiência Cardíaca/fisiopatologia , Feminino , Método Duplo-Cego , Idoso , Volume Sistólico/efeitos dos fármacos , Pessoa de Meia-Idade , Estudos Cross-Over , Tolerância ao Exercício/efeitos dos fármacos , Administração Oral , Função Ventricular Esquerda/efeitos dos fármacos , Resultado do Tratamento , Ésteres/administração & dosagem , Cetonas/administração & dosagem
10.
N Engl J Med ; 387(21): 1947-1956, 2022 11 24.
Artigo em Inglês | MEDLINE | ID: mdl-36342151

RESUMO

BACKGROUND: Despite advances in defibrillation technology, shock-refractory ventricular fibrillation remains common during out-of-hospital cardiac arrest. Double sequential external defibrillation (DSED; rapid sequential shocks from two defibrillators) and vector-change (VC) defibrillation (switching defibrillation pads to an anterior-posterior position) have been proposed as defibrillation strategies to improve outcomes in patients with refractory ventricular fibrillation. METHODS: We conducted a cluster-randomized trial with crossover among six Canadian paramedic services to evaluate DSED and VC defibrillation as compared with standard defibrillation in adult patients with refractory ventricular fibrillation during out-of-hospital cardiac arrest. Patients were treated with one of these three techniques according to the strategy that was randomly assigned to the paramedic service. The primary outcome was survival to hospital discharge. Secondary outcomes included termination of ventricular fibrillation, return of spontaneous circulation, and a good neurologic outcome, defined as a modified Rankin scale score of 2 or lower (indicating no symptoms to slight disability) at hospital discharge. RESULTS: A total of 405 patients were enrolled before the data and safety monitoring board stopped the trial because of the coronavirus disease 2019 pandemic. A total of 136 patients (33.6%) were assigned to receive standard defibrillation, 144 (35.6%) to receive VC defibrillation, and 125 (30.9%) to receive DSED. Survival to hospital discharge was more common in the DSED group than in the standard group (30.4% vs. 13.3%; relative risk, 2.21; 95% confidence interval [CI], 1.33 to 3.67) and more common in the VC group than in the standard group (21.7% vs. 13.3%; relative risk, 1.71; 95% CI, 1.01 to 2.88). DSED but not VC defibrillation was associated with a higher percentage of patients having a good neurologic outcome than standard defibrillation (relative risk, 2.21 [95% CI, 1.26 to 3.88] and 1.48 [95% CI, 0.81 to 2.71], respectively). CONCLUSIONS: Among patients with refractory ventricular fibrillation, survival to hospital discharge occurred more frequently among those who received DSED or VC defibrillation than among those who received standard defibrillation. (Funded by the Heart and Stroke Foundation of Canada; DOSE VF ClinicalTrials.gov number, NCT04080986.).


Assuntos
Cardioversão Elétrica , Parada Cardíaca Extra-Hospitalar , Fibrilação Ventricular , Adulto , Humanos , Canadá , Desfibriladores , Cardioversão Elétrica/efeitos adversos , Cardioversão Elétrica/instrumentação , Cardioversão Elétrica/métodos , Parada Cardíaca Extra-Hospitalar/mortalidade , Parada Cardíaca Extra-Hospitalar/terapia , Fibrilação Ventricular/mortalidade , Fibrilação Ventricular/terapia , Estudos Cross-Over , Análise por Conglomerados
11.
N Engl J Med ; 387(19): 1759-1769, 2022 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-36278971

RESUMO

BACKGROUND: Invasive mechanical ventilation in critically ill adults involves adjusting the fraction of inspired oxygen to maintain arterial oxygen saturation. The oxygen-saturation target that will optimize clinical outcomes in this patient population remains unknown. METHODS: In a pragmatic, cluster-randomized, cluster-crossover trial conducted in the emergency department and medical intensive care unit at an academic center, we assigned adults who were receiving mechanical ventilation to a lower target for oxygen saturation as measured by pulse oximetry (Spo2) (90%; goal range, 88 to 92%), an intermediate target (94%; goal range, 92 to 96%), or a higher target (98%; goal range, 96 to 100%). The primary outcome was the number of days alive and free of mechanical ventilation (ventilator-free days) through day 28. The secondary outcome was death by day 28, with data censored at hospital discharge. RESULTS: A total of 2541 patients were included in the primary analysis. The median number of ventilator-free days was 20 (interquartile range, 0 to 25) in the lower-target group, 21 (interquartile range, 0 to 25) in the intermediate-target group, and 21 (interquartile range, 0 to 26) in the higher-target group (P = 0.81). In-hospital death by day 28 occurred in 281 of the 808 patients (34.8%) in the lower-target group, 292 of the 859 patients (34.0%) in the intermediate-target group, and 290 of the 874 patients (33.2%) in the higher-target group. The incidences of cardiac arrest, arrhythmia, myocardial infarction, stroke, and pneumothorax were similar in the three groups. CONCLUSIONS: Among critically ill adults receiving invasive mechanical ventilation, the number of ventilator-free days did not differ among groups in which a lower, intermediate, or higher Spo2 target was used. (Supported by the National Heart, Lung, and Blood Institute and others; PILOT ClinicalTrials.gov number, NCT03537937.).


Assuntos
Estado Terminal , Oxigênio , Respiração Artificial , Adulto , Humanos , Estado Terminal/terapia , Mortalidade Hospitalar , Unidades de Terapia Intensiva , Oxigênio/administração & dosagem , Oxigênio/sangue , Oxigênio/uso terapêutico , Respiração Artificial/métodos , Cuidados Críticos/métodos , Estudos Cross-Over , Serviço Hospitalar de Emergência , Centros Médicos Acadêmicos , Oximetria
12.
N Engl J Med ; 386(3): 209-219, 2022 01 20.
Artigo em Inglês | MEDLINE | ID: mdl-35045227

RESUMO

BACKGROUND: The possible advantage of hybrid closed-loop therapy (i.e., artificial pancreas) over sensor-augmented pump therapy in very young children with type 1 diabetes is unclear. METHODS: In this multicenter, randomized, crossover trial, we recruited children 1 to 7 years of age with type 1 diabetes who were receiving insulin-pump therapy at seven centers across Austria, Germany, Luxembourg, and the United Kingdom. Participants received treatment in two 16-week periods, in random order, in which the closed-loop system was compared with sensor-augmented pump therapy (control). The primary end point was the between-treatment difference in the percentage of time that the sensor glucose measurement was in the target range (70 to 180 mg per deciliter) during each 16-week period. The analysis was conducted according to the intention-to-treat principle. Key secondary end points included the percentage of time spent in a hyperglycemic state (glucose level, >180 mg per deciliter), the glycated hemoglobin level, the mean sensor glucose level, and the percentage of time spent in a hypoglycemic state (glucose level, <70 mg per deciliter). Safety was assessed. RESULTS: A total of 74 participants underwent randomization. The mean (±SD) age of the participants was 5.6±1.6 years, and the baseline glycated hemoglobin level was 7.3±0.7%. The percentage of time with the glucose level in the target range was 8.7 percentage points (95% confidence interval [CI], 7.4 to 9.9) higher during the closed-loop period than during the control period (P<0.001). The mean adjusted difference (closed-loop minus control) in the percentage of time spent in a hyperglycemic state was -8.5 percentage points (95% CI, -9.9 to -7.1), the difference in the glycated hemoglobin level was -0.4 percentage points (95% CI, -0.5 to -0.3), and the difference in the mean sensor glucose level was -12.3 mg per deciliter (95% CI, -14.8 to -9.8) (P<0.001 for all comparisons). The time spent in a hypoglycemic state was similar with the two treatments (P = 0.74). The median time spent in the closed-loop mode was 95% (interquartile range, 92 to 97) over the 16-week closed-loop period. One serious adverse event of severe hypoglycemia occurred during the closed-loop period. One serious adverse event that was deemed to be unrelated to treatment occurred. CONCLUSIONS: A hybrid closed-loop system significantly improved glycemic control in very young children with type 1 diabetes, without increasing the time spent in hypoglycemia. (Funded by the European Commission and others; ClinicalTrials.gov number, NCT03784027.).


Assuntos
Diabetes Mellitus Tipo 1/tratamento farmacológico , Controle Glicêmico/instrumentação , Hipoglicemiantes/administração & dosagem , Sistemas de Infusão de Insulina , Insulina/administração & dosagem , Pâncreas Artificial , Algoritmos , Glicemia/análise , Criança , Pré-Escolar , Estudos Cross-Over , Desenho de Equipamento , Feminino , Hemoglobinas Glicadas/análise , Controle Glicêmico/métodos , Humanos , Hiperglicemia/diagnóstico , Lactente , Masculino
13.
Ann Neurol ; 95(6): 1205-1219, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38501317

RESUMO

OBJECTIVE: The aim of this study was to investigate the cognitive effects of unilateral directional versus ring subthalamic nucleus deep brain stimulation (STN DBS) in patients with advanced Parkinson's disease. METHODS: We examined 31 participants who underwent unilateral STN DBS (left n = 17; right n = 14) as part of an National Institutes of Health (NIH)-sponsored randomized, double-blind, crossover study contrasting directional versus ring stimulation. All participants received unilateral DBS implants in the hemisphere more severely affected by motor parkinsonism. Measures of cognition included verbal fluency, auditory-verbal memory, and response inhibition. We used mixed linear models to contrast the effects of directional versus ring stimulation and implant hemisphere on longitudinal cognitive function. RESULTS: Crossover analyses showed no evidence for group-level changes in cognitive performance related to directional versus ring stimulation. Implant hemisphere, however, impacted cognition in several ways. Left STN participants had lower baseline verbal fluency than patients with right implants (t [20.66 = -2.50, p = 0.02]). Verbal fluency declined after left (p = 0.013) but increased after right STN DBS (p < 0.001), and response inhibition was faster following right STN DBS (p = 0.031). Regardless of hemisphere, delayed recall declined modestly over time versus baseline (p = 0.001), and immediate recall was unchanged. INTERPRETATION: Directional versus ring STN DBS did not differentially affect cognition. Similar to prior bilateral DBS studies, unilateral left stimulation worsened verbal fluency performance. In contrast, unilateral right STN surgery increased performance on verbal fluency and response inhibition tasks. Our findings raise the hypothesis that unilateral right STN DBS in selected patients with predominant right brain motor parkinsonism could mitigate declines in verbal fluency associated with the bilateral intervention. ANN NEUROL 2024;95:1205-1219.


Assuntos
Cognição , Estudos Cross-Over , Estimulação Encefálica Profunda , Doença de Parkinson , Núcleo Subtalâmico , Humanos , Estimulação Encefálica Profunda/efeitos adversos , Estimulação Encefálica Profunda/métodos , Doença de Parkinson/terapia , Doença de Parkinson/fisiopatologia , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Método Duplo-Cego , Cognição/fisiologia
14.
Ann Neurol ; 95(5): 849-857, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38366778

RESUMO

OBJECTIVE: One proposed mechanism of disease progression in Parkinson's disease includes the interplay of endogenous dopamine toxicity and mitochondrial dysfunction. However, the in-vivo effects of exogenous dopamine administration on cerebral bioenergetics are unknown. METHODS: We performed a double-blinded, cross-over, placebo-controlled trial. Participants received either 200/50 mg levodopa/benserazide or a placebo and vice versa on the second study visit. Clinical assessments and multimodal neuroimaging were performed, including 31phosphorus magnetic resonance spectroscopy of the basal ganglia and the midbrain. RESULTS: In total, 20 (6 female) patients with Parkinson's disease and 22 sex- and age-matched healthy controls (10 female) were enrolled. Treatment with levodopa/benserazide but not with placebo resulted in a substantial reduction of high-energy phosphorus-containing metabolites in the basal ganglia (patients with Parkinson's disease: -40%; healthy controls: -39%) but not in the midbrain. There were no differences in high-energy phosphorus-containing metabolites for patients with Parkinson's disease compared to healthy controls in the OFF state and treatment response. INTERPRETATION: Exogenously administered levodopa/benserazide strongly interferes with basal ganglia high-energy phosphorus-containing metabolite levels in both groups. The lack of effects on midbrain levels suggests that the observed changes are limited to the site of dopamine action. ANN NEUROL 2024;95:849-857.


Assuntos
Gânglios da Base , Benserazida , Estudos Cross-Over , Metabolismo Energético , Levodopa , Doença de Parkinson , Humanos , Feminino , Masculino , Pessoa de Meia-Idade , Gânglios da Base/metabolismo , Gânglios da Base/efeitos dos fármacos , Gânglios da Base/diagnóstico por imagem , Idoso , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/metabolismo , Doença de Parkinson/diagnóstico por imagem , Benserazida/farmacologia , Método Duplo-Cego , Metabolismo Energético/efeitos dos fármacos , Antiparkinsonianos , Combinação de Medicamentos , Espectroscopia de Ressonância Magnética/métodos
15.
Mol Psychiatry ; 29(5): 1241-1252, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38243074

RESUMO

Abnormalities in functional brain networks (functional connectome) are increasingly implicated in people at Clinical High Risk for Psychosis (CHR-P). Intranasal oxytocin, a potential novel treatment for the CHR-P state, modulates network topology in healthy individuals. However, its connectomic effects in people at CHR-P remain unknown. Forty-seven men (30 CHR-P and 17 healthy controls) received acute challenges of both intranasal oxytocin 40 IU and placebo in two parallel randomised, double-blind, placebo-controlled cross-over studies which had similar but not identical designs. Multi-echo resting-state fMRI data was acquired at approximately 1 h post-dosing. Using a graph theoretical approach, the effects of group (CHR-P vs healthy control), treatment (oxytocin vs placebo) and respective interactions were tested on graph metrics describing the topology of the functional connectome. Group effects were observed in 12 regions (all pFDR < 0.05) most localised to the frontoparietal network. Treatment effects were found in 7 regions (all pFDR < 0.05) predominantly within the ventral attention network. Our major finding was that many effects of oxytocin on network topology differ across CHR-P and healthy individuals, with significant interaction effects observed in numerous subcortical regions strongly implicated in psychosis onset, such as the thalamus, pallidum and nucleus accumbens, and cortical regions which localised primarily to the default mode network (12 regions, all pFDR < 0.05). Collectively, our findings provide new insights on aberrant functional brain network organisation associated with psychosis risk and demonstrate, for the first time, that oxytocin modulates network topology in brain regions implicated in the pathophysiology of psychosis in a clinical status (CHR-P vs healthy control) specific manner.


Assuntos
Encéfalo , Conectoma , Imageamento por Ressonância Magnética , Ocitocina , Transtornos Psicóticos , Humanos , Ocitocina/farmacologia , Ocitocina/administração & dosagem , Masculino , Conectoma/métodos , Transtornos Psicóticos/tratamento farmacológico , Transtornos Psicóticos/fisiopatologia , Imageamento por Ressonância Magnética/métodos , Método Duplo-Cego , Adulto , Encéfalo/efeitos dos fármacos , Encéfalo/fisiopatologia , Adulto Jovem , Estudos Cross-Over , Administração Intranasal , Rede Nervosa/efeitos dos fármacos , Rede Nervosa/fisiopatologia , Rede Nervosa/diagnóstico por imagem , Adolescente , Risco
16.
Arterioscler Thromb Vasc Biol ; 44(2): 435-451, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38126174

RESUMO

BACKGROUND: Humans spend much of the day in the postprandial state. However, most research and clinical guidelines on plasma lipids pertain to blood drawn after a 12-hour fast. We aimed to study the metabolic differences of apoB lipoproteins between the fasting and postprandial states. METHODS: We investigated plasma apoB metabolism using stable isotope tracers in 12 adult volunteers under fasting and continuous postprandial conditions in a randomized crossover study. We determined the metabolism of apoB in multiple lipoprotein subfractions, including light and dense VLDLs (very-low-density lipoproteins), IDLs (intermediate-density lipoproteins), and light and dense LDLs (low-density lipoproteins) that do or do not contain apoE or apoC3. RESULTS: A major feature of the postprandial state is 50% lower secretion rate of triglyceride-rich lipoproteins and concurrent slowdown of their catabolism in circulation, as shown by 34% to 55% lower rate constants for the metabolic pathways of conversion by lipolysis from larger to smaller lipoproteins and direct clearance of lipoproteins from the circulation. In addition, the secretion pattern of apoB lipoprotein phenotypes was shifted from particles containing apoE and apoC3 in the fasting state to those without either protein in the postprandial state. CONCLUSIONS: Overall, during the fasting state, hepatic apoB lipoprotein metabolism is activated, characterized by increased production, transport, and clearance. After food intake, endogenous apoB lipoprotein metabolism is globally reduced as appropriate to balance dietary input to maintain the supply of energy to peripheral tissues.


Assuntos
Apolipoproteínas B , Lipoproteínas VLDL , Adulto , Humanos , Estudos Cross-Over , Apolipoproteína B-100 , Triglicerídeos , Lipoproteínas LDL , Apolipoproteínas E/metabolismo , Ingestão de Alimentos
17.
Arterioscler Thromb Vasc Biol ; 44(6): 1407-1418, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38695168

RESUMO

BACKGROUND: LCAT (lecithin cholesterol acyl transferase) catalyzes the conversion of unesterified, or free cholesterol, to cholesteryl ester, which moves from the surface of HDL (high-density lipoprotein) into the neutral lipid core. As this iterative process continues, nascent lipid-poor HDL is converted to a series of larger, spherical cholesteryl ester-enriched HDL particles that can be cleared by the liver in a process that has been termed reverse cholesterol transport. METHODS: We conducted a randomized, placebocontrolled, crossover study in 5 volunteers with atherosclerotic cardiovascular disease, to examine the effects of an acute increase of recombinant human (rh) LCAT via intravenous administration (300-mg loading dose followed by 150 mg at 48 hours) on the in vivo metabolism of HDL APO (apolipoprotein)A1 and APOA2, and the APOB100-lipoproteins, very low density, intermediate density, and low-density lipoproteins. RESULTS: As expected, recombinant human LCAT treatment significantly increased HDL-cholesterol (34.9 mg/dL; P≤0.001), and this was mostly due to the increase in cholesteryl ester content (33.0 mg/dL; P=0.014). This change did not affect the fractional clearance or production rates of HDL-APOA1 and HDL-APOA2. There were also no significant changes in the metabolism of APOB100-lipoproteins. CONCLUSIONS: Our results suggest that an acute increase in LCAT activity drives greater flux of cholesteryl ester through the reverse cholesterol transport pathway without significantly altering the clearance and production of the main HDL proteins and without affecting the metabolism of APOB100-lipoproteins. Long-term elevations of LCAT might, therefore, have beneficial effects on total body cholesterol balance and atherogenesis.


Assuntos
Apolipoproteína A-II , Apolipoproteína A-I , HDL-Colesterol , Estudos Cross-Over , Fosfatidilcolina-Esterol O-Aciltransferase , Proteínas Recombinantes , Humanos , Fosfatidilcolina-Esterol O-Aciltransferase/metabolismo , Masculino , Apolipoproteína A-I/sangue , Pessoa de Meia-Idade , HDL-Colesterol/sangue , Apolipoproteína A-II/sangue , Feminino , Ésteres do Colesterol/sangue , Ésteres do Colesterol/metabolismo , Aterosclerose/tratamento farmacológico , Aterosclerose/enzimologia , Aterosclerose/sangue , Apolipoproteína B-100/sangue , Idoso , Adulto , Lipoproteínas/sangue , Lipoproteínas/metabolismo
18.
Cereb Cortex ; 34(6)2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38850217

RESUMO

This study aimed to investigate the effects of high-definition transcranial direct current stimulation on ankle force sense and underlying cerebral hemodynamics. Sixteen healthy adults (8 males and 8 females) were recruited in the study. Each participant received either real or sham high-definition transcranial direct current stimulation interventions in a randomly assigned order on 2 visits. An isokinetic dynamometer was used to assess the force sense of the dominant ankle; while the functional near-infrared spectroscopy was employed to monitor the hemodynamics of the sensorimotor cortex. Two-way analyses of variance with repeated measures and Pearson correlation analyses were performed. The results showed that the absolute error and root mean square error of ankle force sense dropped more after real stimulation than after sham stimulation (dropped by 23.4% vs. 14.9% for absolute error, and 20.0% vs. 10.2% for root mean square error). The supplementary motor area activation significantly increased after real high-definition transcranial direct current stimulation. The decrease in interhemispheric functional connectivity within the Brodmann's areas 6 was significantly correlated with ankle force sense improvement after real high-definition transcranial direct current stimulation. In conclusion, high-definition transcranial direct current stimulation can be used as a potential intervention for improving ankle force sense. Changes in cerebral hemodynamics could be one of the explanations for the energetic effect of high-definition transcranial direct current stimulation.


Assuntos
Tornozelo , Espectroscopia de Luz Próxima ao Infravermelho , Estimulação Transcraniana por Corrente Contínua , Adulto , Feminino , Humanos , Masculino , Adulto Jovem , Tornozelo/fisiologia , Circulação Cerebrovascular/fisiologia , Hemodinâmica/fisiologia , Córtex Motor/fisiologia , Estimulação Transcraniana por Corrente Contínua/métodos , Estudos Cross-Over
19.
Proc Natl Acad Sci U S A ; 119(51): e2211534119, 2022 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-36508653

RESUMO

Food fortification is an effective strategy to address vitamin A (VitA) deficiency, which is the leading cause of childhood blindness and drastically increases mortality from severe infections. However, VitA food fortification remains challenging due to significant degradation during storage and cooking. We utilized an FDA-approved, thermostable, and pH-responsive basic methacrylate copolymer (BMC) to encapsulate and stabilize VitA in microparticles (MPs). Encapsulation of VitA in VitA-BMC MPs greatly improved stability during simulated cooking conditions and long-term storage. VitA absorption was nine times greater from cooked MPs than from cooked free VitA in rats. In a randomized controlled cross-over study in healthy premenopausal women, VitA was readily released from MPs after consumption and had a similar absorption profile to free VitA. This VitA encapsulation technology will enable global food fortification strategies toward eliminating VitA deficiency.


Assuntos
Deficiência de Vitamina A , Vitamina A , Feminino , Ratos , Animais , Alimentos Fortificados , Estudos Cross-Over , Culinária , Micronutrientes
20.
J Am Soc Nephrol ; 35(2): 189-201, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38073038

RESUMO

SIGNIFICANCE STATEMENT: The effect of sodium-glucose cotransporter-2 inhibitors (SGLT2i) on regional tubular sodium handling is poorly understood in humans. In this study, empagliflozin substantially decreased lithium reabsorption in the proximal tubule (PT) (a marker of proximal tubular sodium reabsorption), a magnitude out of proportion to that expected with only inhibition of sodium-glucose cotransporter-2. This finding was not driven by an "osmotic diuretic" effect; however, several parameters changed in a manner consistent with inhibition of the sodium-hydrogen exchanger 3. The large changes in proximal tubular handling were acutely buffered by increased reabsorption in both the loop of Henle and the distal nephron, resulting in the observed modest acute natriuresis with these agents. After 14 days of empagliflozin, natriuresis waned due to increased reabsorption in the PT and/or loop of Henle. These findings confirm in humans that SGLT2i have complex and important effects on renal tubular solute handling. BACKGROUND: The effect of SGLT2i on regional tubular sodium handling is poorly understood in humans but may be important for the cardiorenal benefits. METHODS: This study used a previously reported randomized, placebo-controlled crossover study of empagliflozin 10 mg daily in patients with diabetes and heart failure. Sodium handling in the PT, loop of Henle (loop), and distal nephron was assessed at baseline and day 14 using fractional excretion of lithium (FELi), capturing PT/loop sodium reabsorption. Assessments were made with and without antagonism of sodium reabsorption through the loop using bumetanide. RESULTS: Empagliflozin resulted in a large decrease in sodium reabsorption in the PT (increase in FELi=7.5%±10.6%, P = 0.001), with several observations suggesting inhibition of PT sodium hydrogen exchanger 3. In the absence of renal compensation, this would be expected to result in approximately 40 g of sodium excretion/24 hours with normal kidney function. However, rapid tubular compensation occurred with increased sodium reabsorption both in the loop ( P < 0.001) and distal nephron ( P < 0.001). Inhibition of sodium-glucose cotransporter-2 did not attenuate over 14 days of empagliflozin ( P = 0.14). However, there were significant reductions in FELi ( P = 0.009), fractional excretion of sodium ( P = 0.004), and absolute fractional distal sodium reabsorption ( P = 0.036), indicating that chronic adaptation to SGLT2i results primarily from increased reabsorption in the loop and/or PT. CONCLUSIONS: Empagliflozin caused substantial redistribution of intrarenal sodium delivery and reabsorption, providing mechanistic substrate to explain some of the benefits of this class. Importantly, the large increase in sodium exit from the PT was balanced by distal compensation, consistent with SGLT2i excellent safety profile. CLINICAL TRIAL REGISTRY NAME AND REGISTRATION NUMBER: ClinicalTrials.gov ( NCT03027960 ).


Assuntos
Compostos Benzidrílicos , Glucosídeos , Insuficiência Cardíaca , Inibidores do Transportador 2 de Sódio-Glicose , Humanos , Sódio , Inibidores do Transportador 2 de Sódio-Glicose/farmacologia , Inibidores do Transportador 2 de Sódio-Glicose/uso terapêutico , Lítio , Estudos Cross-Over , Néfrons , Insuficiência Cardíaca/tratamento farmacológico , Diuréticos , Glucose
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