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1.
Cell ; 187(7): 1666-1684.e26, 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38490194

RESUMO

Diminished hepatocyte regeneration is a key feature of acute and chronic liver diseases and after extended liver resections, resulting in the inability to maintain or restore a sufficient functional liver mass. Therapies to restore hepatocyte regeneration are lacking, making liver transplantation the only curative option for end-stage liver disease. Here, we report on the structure-based development and characterization (nuclear magnetic resonance [NMR] spectroscopy) of first-in-class small molecule inhibitors of the dual-specificity kinase MKK4 (MKK4i). MKK4i increased liver regeneration upon hepatectomy in murine and porcine models, allowed for survival of pigs in a lethal 85% hepatectomy model, and showed antisteatotic and antifibrotic effects in liver disease mouse models. A first-in-human phase I trial (European Union Drug Regulating Authorities Clinical Trials [EudraCT] 2021-000193-28) with the clinical candidate HRX215 was conducted and revealed excellent safety and pharmacokinetics. Clinical trials to probe HRX215 for prevention/treatment of liver failure after extensive oncological liver resections or after transplantation of small grafts are warranted.


Assuntos
Inibidores Enzimáticos , Falência Hepática , MAP Quinase Quinase 4 , Animais , Humanos , Camundongos , Hepatectomia/métodos , Hepatócitos , Fígado , Hepatopatias/tratamento farmacológico , Falência Hepática/tratamento farmacológico , Falência Hepática/prevenção & controle , Regeneração Hepática , Suínos , MAP Quinase Quinase 4/antagonistas & inibidores , Inibidores Enzimáticos/uso terapêutico
2.
Nature ; 593(7857): 67-73, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33953412

RESUMO

Transition metal (oxy)hydroxides are promising electrocatalysts for the oxygen evolution reaction1-3. The properties of these materials evolve dynamically and heterogeneously4 with applied voltage through ion insertion redox reactions, converting materials that are inactive under open circuit conditions into active electrocatalysts during operation5. The catalytic state is thus inherently far from equilibrium, which complicates its direct observation. Here, using a suite of correlative operando scanning probe and X-ray microscopy techniques, we establish a link between the oxygen evolution activity and the local operational chemical, physical and electronic nanoscale structure of single-crystalline ß-Co(OH)2 platelet particles. At pre-catalytic voltages, the particles swell to form an α-CoO2H1.5·0.5H2O-like structure-produced through hydroxide intercalation-in which the oxidation state of cobalt is +2.5. Upon increasing the voltage to drive oxygen evolution, interlayer water and protons de-intercalate to form contracted ß-CoOOH particles that contain Co3+ species. Although these transformations manifest heterogeneously through the bulk of the particles, the electrochemical current is primarily restricted to their edge facets. The observed Tafel behaviour is correlated with the local concentration of Co3+ at these reactive edge sites, demonstrating the link between bulk ion-insertion and surface catalytic activity.

3.
Nat Mater ; 2024 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-39420105

RESUMO

Delithiation of layered oxide electrodes triggers irreversible oxygen loss, one of the primary degradation modes in lithium-ion batteries. However, the delithiation-dependent mechanisms of oxygen loss remain poorly understood. Here we investigate the oxygen non-stoichiometry in Li1.18-xNi0.21Mn0.53Co0.08O2-δ electrodes as a function of Li content by using cycling protocols with long open-circuit voltage steps at varying states of charge. Surprisingly, we observe substantial oxygen loss even at moderate delithiation, corresponding to 2.5, 4.0 and 7.6 ml O2 per gram of Li1.18-xNi0.21Mn0.53Co0.08O2-δ after resting at upper capacity cut-offs of 135, 200 and 265 mAh g-1 for 100 h. Our observations suggest an intrinsic oxygen instability consistent with predictions of high oxygen activity at intermediate potentials versus Li/Li+. In addition, we observe a large chemical expansion coefficient with respect to oxygen non-stoichiometry, which is about three times greater than those of classical oxygen-deficient materials such as fluorite and perovskite oxides. Our work challenges the conventional wisdom that deep delithiation is a necessary condition for oxygen loss in layered oxide electrodes and highlights the importance of calendar ageing for investigating oxygen stability.

4.
Nano Lett ; 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-39404229

RESUMO

The kinetics of interfacial ion insertion govern the uniformity of electrochemical reactions, playing a crucial role in lithium-ion battery performance. In two-dimensional lithium-conducting layered-oxide battery particles, variation in insertion rates across insertion channels remains unclear due to poorly defined crystal orientation at the solid-liquid interface and solid-state-lithium-diffusion length. This ambiguity complicates understanding inhomogeneous lithium-insertion channels activation. A systematic study requires crystallographically predefined interfaces and in situ lithium-concentration mapping. Here, we fabricated a freestanding, (104)-oriented-LiNi1/3Mn1/3Co1/3O2 single-crystal thin film using dissolution-induced release and performed in situ scanning-transmission-X-ray-microscopy to spatially resolve lithium-insertion at well-defined-interfaces. We observed heterogeneous lithium-concentration evolution due to channel-by-channel insertion rate variation, despite the potential for homogeneous lithium distribution via a solid-solution-phase at equilibrium in NMC111. Increasing current density exacerbates this heterogeneity, highlighting channel-by-channel variation. Our findings provide critical insights into battery electrode utilization and lifetime management, potentially guiding the design of more efficient and durable lithium-ion batteries.

5.
J Infect Dis ; 230(4): 878-888, 2024 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-38839047

RESUMO

BACKGROUND: Pregnant people with coronavirus disease 2019 (COVID-19) experience higher risk for severe disease and adverse pregnancy outcomes, but no pharmacokinetic (PK) data exist to support dosing of COVID-19 therapeutics during pregnancy. We report PK and safety data for intravenous remdesivir in pregnancy. METHODS: IMPAACT 2032 was a phase 4 prospective, open-label, nonrandomized opportunistic study of hospitalized pregnant and nonpregnant women receiving intravenous remdesivir as part of clinical care. Intensive PK sampling was performed on infusion days 3, 4, or 5 with collection of plasma and peripheral blood mononuclear cells (PBMCs). Safety data were recorded from first infusion through 4 weeks after last infusion and at delivery. Geometric mean ratios (GMR) (90% confidence intervals [CI]) of PK parameters between pregnant and nonpregnant women were calculated. RESULTS: Fifty-three participants initiated remdesivir (25 pregnant; median gestational age, 27.6 weeks; interquartile range, 24.9-31.0 weeks). Plasma exposures of remdesivir, its 2 major metabolites (GS-704277 and GS-441524), and the free remdesivir fraction were similar between pregnant and nonpregnant participants. Concentrations of the active triphosphate (GS-443902) in PBMCs increased 2.04-fold (90% CI, 1.35-3.03) with each additional infusion in nonpregnant versus pregnant participants. Three adverse events in nonpregnant participants were related to treatment (1 grade 3; 2 grade 2 resulting in treatment discontinuation). There were no treatment-related adverse pregnancy outcomes or congenital anomalies detected. CONCLUSIONS: Plasma remdesivir PK parameters were comparable between pregnant and nonpregnant women, and no safety concerns were identified based on our limited data. These findings suggest no dose adjustments are indicated for intravenous remdesivir during pregnancy. CLINICAL TRIALS REGISTRATION: NCT04582266.


Assuntos
Monofosfato de Adenosina , Alanina , Antivirais , COVID-19 , Complicações Infecciosas na Gravidez , SARS-CoV-2 , Humanos , Feminino , Gravidez , Alanina/análogos & derivados , Alanina/farmacocinética , Alanina/efeitos adversos , Alanina/administração & dosagem , Alanina/uso terapêutico , Monofosfato de Adenosina/análogos & derivados , Monofosfato de Adenosina/farmacocinética , Monofosfato de Adenosina/efeitos adversos , Monofosfato de Adenosina/administração & dosagem , Monofosfato de Adenosina/uso terapêutico , Adulto , Antivirais/farmacocinética , Antivirais/efeitos adversos , Antivirais/administração & dosagem , Antivirais/uso terapêutico , Complicações Infecciosas na Gravidez/tratamento farmacológico , Complicações Infecciosas na Gravidez/virologia , Estudos Prospectivos , SARS-CoV-2/efeitos dos fármacos , Tratamento Farmacológico da COVID-19 , Adulto Jovem
6.
Proc Natl Acad Sci U S A ; 118(3)2021 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-33436411

RESUMO

Biominerals such as seashells, coral skeletons, bone, and tooth enamel are optically anisotropic crystalline materials with unique nanoscale and microscale organization that translates into exceptional macroscopic mechanical properties, providing inspiration for engineering new and superior biomimetic structures. Using Seriatopora aculeata coral skeleton as a model, here, we experimentally demonstrate X-ray linear dichroic ptychography and map the c-axis orientations of the aragonite (CaCO3) crystals. Linear dichroic phase imaging at the oxygen K-edge energy shows strong polarization-dependent contrast and reveals the presence of both narrow (<35°) and wide (>35°) c-axis angular spread in the coral samples. These X-ray ptychography results are corroborated by four-dimensional (4D) scanning transmission electron microscopy (STEM) on the same samples. Evidence of co-oriented, but disconnected, corallite subdomains indicates jagged crystal boundaries consistent with formation by amorphous nanoparticle attachment. We expect that the combination of X-ray linear dichroic ptychography and 4D STEM could be an important multimodal tool to study nano-crystallites, interfaces, nucleation, and mineral growth of optically anisotropic materials at multiple length scales.


Assuntos
Antozoários/química , Biomimética , Biomineralização , Cristalinas/química , Animais , Anisotropia , Antozoários/ultraestrutura , Carbonato de Cálcio/química , Cristalinas/ultraestrutura , Microscopia Eletrônica de Transmissão e Varredura , Minerais/química , Radiografia , Engenharia Tecidual , Raios X
7.
Int J Mol Sci ; 25(3)2024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-38338944

RESUMO

We aimed to test how the postbiotic butyrate impacts select gut bacteria, small intestinal epithelial integrity, and microvascular endothelial activation during acute ethanol exposure in mice and primary human intestinal microvascular endothelial cells (HIMECs). Supplementation during an acute ethanol challenge with or without tributyrin, a butyrate prodrug, was delivered to C57BL/6 mice. A separate group of mice received 3 days of clindamycin prior to the acute ethanol challenge. Upon euthanasia, blood endotoxin, cecal bacteria, jejunal barrier integrity, and small intestinal lamina propria dendritic cells were assessed. HIMECs were tested for activation following exposure to ethanol ± lipopolysaccharide (LPS) and sodium butyrate. Tributyrin supplementation protected a butyrate-generating microbe during ethanol and antibiotic exposure. Tributyrin rescued ethanol-induced disruption in jejunal epithelial barrier, elevated plasma endotoxin, and increased mucosal vascular addressin cell-adhesion molecule-1 (MAdCAM-1) expression in intestinal microvascular endothelium. These protective effects of tributyrin coincided with a tolerogenic dendritic response in the intestinal lamina propria. Lastly, sodium butyrate pre- and co-treatment attenuated the direct effects of ethanol and LPS on MAdCAM-1 induction in the HIMECs from a patient with ulcerative colitis. Tributyrin supplementation protects small intestinal epithelial and microvascular barrier integrity and modulates microvascular endothelial activation and dendritic tolerizing function during a state of gut dysbiosis and acute ethanol challenge.


Assuntos
Células Endoteliais , Etanol , Camundongos , Humanos , Animais , Etanol/farmacologia , Ácido Butírico/farmacologia , Ácido Butírico/metabolismo , Lipopolissacarídeos/farmacologia , Camundongos Endogâmicos C57BL , Mucosa Intestinal/metabolismo
8.
Antimicrob Agents Chemother ; 67(11): e0073723, 2023 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-37882552

RESUMO

Physiological changes during pregnancy may alter the pharmacokinetics (PK) of antituberculosis drugs. The International Maternal Pediatric Adolescent AIDS Clinical Trials Network P1026s was a multicenter, phase IV, observational, prospective PK and safety study of antiretroviral and antituberculosis drugs administered as part of clinical care in pregnant persons living with and without HIV. We assessed the effects of pregnancy on rifampin, isoniazid, ethambutol, and pyrazinamide PK in pregnant and postpartum (PP) persons without HIV treated for drug-susceptible tuberculosis disease. Daily antituberculosis treatment was prescribed following World Health Organization-recommended weight-band dosing guidelines. Steady-state 12-hour PK profiles of rifampin, isoniazid, ethambutol, and pyrazinamide were performed during second trimester (2T), third trimester (3T), and 2-8 of weeks PP. PK parameters were characterized using noncompartmental analysis, and comparisons were made using geometric mean ratios (GMRs) with 90% confidence intervals (CI). Twenty-seven participants were included: 11 African, 9 Asian, 3 Hispanic, and 4 mixed descent. PK data were available for 17, 21, and 14 participants in 2T, 3T, and PP, respectively. Rifampin and pyrazinamide AUC0-24 and C max in pregnancy were comparable to PP with the GMR between 0.80 and 1.25. Compared to PP, isoniazid AUC0-24 was 25% lower and C max was 23% lower in 3T. Ethambutol AUC0-24 was 39% lower in 3T but limited by a low PP sample size. In summary, isoniazid and ethambutol concentrations were lower during pregnancy compared to PP concentrations, while rifampin and pyrazinamide concentrations were similar. However, the median AUC0-24 for rifampin, isoniazid, and pyrazinamide met the therapeutic targets. The clinical impact of lower isoniazid and ethambutol exposure during pregnancy needs to be determined.


Assuntos
Antituberculosos , Tuberculose , Adolescente , Feminino , Humanos , Gravidez , Antituberculosos/efeitos adversos , Antituberculosos/farmacocinética , Etambutol/efeitos adversos , Etambutol/farmacocinética , Infecções por HIV/tratamento farmacológico , Isoniazida/efeitos adversos , Isoniazida/farmacocinética , Período Pós-Parto , Estudos Prospectivos , Pirazinamida/efeitos adversos , Pirazinamida/farmacocinética , Rifampina/efeitos adversos , Rifampina/farmacocinética , Tuberculose/tratamento farmacológico , Estudos Multicêntricos como Assunto , Ensaios Clínicos Fase IV como Assunto , Estudos Observacionais como Assunto
9.
Nat Mater ; 21(5): 547-554, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35177785

RESUMO

Constitutive laws underlie most physical processes in nature. However, learning such equations in heterogeneous solids (for example, due to phase separation) is challenging. One such relationship is between composition and eigenstrain, which governs the chemo-mechanical expansion in solids. Here we developed a generalizable, physically constrained image-learning framework to algorithmically learn the chemo-mechanical constitutive law at the nanoscale from correlative four-dimensional scanning transmission electron microscopy and X-ray spectro-ptychography images. We demonstrated this approach on LiXFePO4, a technologically relevant battery positive electrode material. We uncovered the functional form of the composition-eigenstrain relation in this two-phase binary solid across the entire composition range (0 ≤ X ≤ 1), including inside the thermodynamically unstable miscibility gap. The learned relation directly validates Vegard's law of linear response at the nanoscale. Our physics-constrained data-driven approach directly visualizes the residual strain field (by removing the compositional and coherency strain), which is otherwise impossible to quantify. Heterogeneities in the residual strain arise from misfit dislocations and were independently verified by X-ray diffraction line profile analysis. Our work provides the means to simultaneously quantify chemical expansion, coherency strain and dislocations in battery electrodes, which has implications on rate capabilities and lifetime. Broadly, this work also highlights the potential of integrating correlative microscopy and image learning for extracting material properties and physics.

10.
Nat Mater ; 20(7): 991-999, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33686277

RESUMO

Layered oxides widely used as lithium-ion battery electrodes are designed to be cycled under conditions that avoid phase transitions. Although the desired single-phase composition ranges are well established near equilibrium, operando diffraction studies on many-particle porous electrodes have suggested phase separation during delithiation. Notably, the separation is not always observed, and never during lithiation. These anomalies have been attributed to irreversible processes during the first delithiation or reversible concentration-dependent diffusion. However, these explanations are not consistent with all experimental observations such as rate and path dependencies and particle-by-particle lithium concentration changes. Here, we show that the apparent phase separation is a dynamical artefact occurring in a many-particle system driven by autocatalytic electrochemical reactions, that is, an interfacial exchange current that increases with the extent of delithiation. We experimentally validate this population-dynamics model using the single-phase material Lix(Ni1/3Mn1/3Co1/3)O2 (0.5 < x < 1) and demonstrate generality with other transition-metal compositions. Operando diffraction and nanoscale oxidation-state mapping unambiguously prove that this fictitious phase separation is a repeatable non-equilibrium effect. We quantitatively confirm the theory with multiple-datastream-driven model extraction. More generally, our study experimentally demonstrates the control of ensemble stability by electro-autocatalysis, highlighting the importance of population dynamics in battery electrodes (even non-phase-separating ones).

11.
World J Surg ; 46(11): 2625-2631, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35854014

RESUMO

BACKGROUND: Bedside percutaneous dilatational tracheostomy (PDT) and percutaneous endoscopic gastrostomy (PEG) are common procedures performed in the intensive care unit (ICU). Venous thromboembolism (VTE) prophylaxis is frequently prescribed to ICU patients and it remains unclear whether pre-procedure discontinuation is necessary. METHODS: This multi-center prospective observational study aimed to describe bleeding rates in patients undergoing bedside PEG or PDT who did or did not have VTE prophylaxis held. Decision to hold prophylaxis was made by the operating physician. The primary endpoint was the rate of peri-procedural bleeding complications. Secondary endpoints included quantification of held doses in the peri-procedural period, rate of venous thromboembolism, and characteristics associated with having prophylaxis held. RESULTS: 91 patients were included over a 2-year period. Patients were on average aged 54 years, 40% female, mostly admitted to the trauma service (59%), and most commonly underwent bedside PDT (59%). Overall, 21% of patients had doses of pre-procedure prophylaxis held. Bleeding events occurred in 1 patient (1.4%) who had prophylaxis continued and in 1 patient (5.0%) who had prophylaxis held, a rate difference of 3.6% (95% CI-9.5%, 16.7%). One bleeding event was managed with bedside surgical repair and one with blood transfusion. There were 10 VTE events, all of whom had prophylaxis continued during the pre-procedure period but 3 had prophylaxis held after the procedure. CONCLUSIONS: Bleeding complications were rare and did not significantly differ depending on whether prophylaxis was held or not. Future research is required to confirm the lack of risk with continuing prophylaxis through bedside procedures.


Assuntos
Tromboembolia Venosa , Anticoagulantes/efeitos adversos , Feminino , Humanos , Masculino , Estudos Prospectivos , Traqueostomia/métodos , Tromboembolia Venosa/etiologia , Tromboembolia Venosa/prevenção & controle
12.
Sensors (Basel) ; 22(2)2022 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-35062412

RESUMO

We calculate the light transmission by a subwavelength plasmonic array using the boundary element method for parallel cylinders with different cross-sections: circular or elliptic with axis ratio 4:1. We demonstrate that plasmonic resonance is sharper for the case of horizontal ellipses. This structure is susceptible to refractive index variations in the media since the high derivatives of reflection and transmission coefficients are near the angle of total internal reflection. To obtain an approximate analytical expression, we used the model of a metallic layer. We explore the "sandwich" structure with an anisotropic film between two dielectrics and demonstrate its quantitative agreement with numerical results.

13.
Pak J Med Sci ; 38(2): 351-355, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35310808

RESUMO

Background and Objective: Maintaining privacy and ensuring confidentiality with patients is paramount to developing an effective patient-provider relationship. This is often challenging in over-crowded Emergency Departments (EDs). This survey was designed to explore patients' perceptions on maintenance of privacy and confidentiality and their subsequent interactions with providers in a busy tertiary care hospital in Karachi. Methods: Trained nursing staff conducted structured interviews with 571 patients who presented to The Indus Hospital (TIH) ED from January to December 2020. All patients were 14 years of age or older, could speak and understand Urdu, and provide informed consent. Patients were asked about their perceptions of privacy and confidentiality in the ED and whether this affected their interactions with providers. Results: Respondents were primarily men (64%) under the age of 45 (62%) presenting for the first time (49%). The majority of patients felt that privacy and confidentiality were maintained, however 10% of patients reported that they had rejected examination due to privacy concerns and 15% of patients reported that they had changed or omitted information provided to a provider due to confidentiality concerns. There was correlation between privacy and confidentiality concerns and patient-provider interactions (p<0.0001). Conclusions: Despite the often over-crowded and busy environment of the ED, patients generally felt that privacy and confidentiality were maintained. Given the correlation between perception and behavior and the importance of an effective patient-provider relationship, particularly in the acute setting when morbidity and mortality is high, initiatives that focus on maintaining privacy and confidentiality should be pursued.

14.
Clin Infect Dis ; 73(6): 969-978, 2021 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-33768226

RESUMO

BACKGROUND: To evaluate the frequency and associated characteristics of chronic comorbid conditions and obstetrical complications among pregnant women with human immunodeficiency virus (HIV) and receiving antiretroviral therapy (ART) in comparison to those without HIV. METHODS: We compared 2 independent concurrent US pregnancy cohorts: (1) with HIV (International Maternal Pediatric Adolescent AIDS Clinical Trials Protocol P1025, 2002-2013) and (2) without HIV (Consortium for Safe Labor Study, 2002-2007). Outcomes were ≥2 chronic comorbid conditions and obstetrical complications. For women with HIV, we assessed whether late prenatal care (≥14 weeks), starting ART in an earlier era (2002-2008), and a detectable viral load at delivery (≥400 copies/mL) were associated with study outcomes. RESULTS: We assessed 2868 deliveries (n = 2574 women) with HIV and receiving ART and 211 910 deliveries (n = 193 170 women) without HIV. Women with HIV were more likely to have ≥2 chronic comorbid conditions versus those without HIV (10 vs 3%; adjusted OR [AOR]: 2.96; 95% CI: 2.58-3.41). Women with HIV were slightly less likely to have obstetrical complications versus those without HIV (both 17%; AOR: .84; 95% CI: .75-.94), but secondarily, higher odds of preterm birth <37 weeks. Late entry to prenatal care and starting ART in an earlier era were associated with a lower likelihood of ≥2 chronic comorbidities and obstetrical complications; detectable viral load at delivery was associated with a higher likelihood of obstetric complications. CONCLUSIONS: Pregnant women with HIV receiving ART have more chronic comorbid conditions, but not necessarily obstetrical complications, than their peers without HIV.


Assuntos
Fármacos Anti-HIV , Infecções por HIV , Complicações Infecciosas na Gravidez , Nascimento Prematuro , Fármacos Anti-HIV/efeitos adversos , Feminino , HIV , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia , Humanos , Recém-Nascido , Transmissão Vertical de Doenças Infecciosas , Gravidez , Complicações Infecciosas na Gravidez/tratamento farmacológico , Complicações Infecciosas na Gravidez/epidemiologia , Gestantes , Estados Unidos/epidemiologia , Carga Viral
15.
J Hepatol ; 74(1): 58-65, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32717289

RESUMO

BACKGROUND & AIMS: Obeticholic acid (OCA) is an agonist of the nuclear bile acid receptor farnesoid X receptor, which regulates hepatic bile acid metabolism. We tested whether OCA treatment would influence hepatic transport of conjugated bile acids in patients with primary biliary cholangitis (PBC) who responded inadequately to treatment with ursodeoxycholic acid (UDCA). METHODS: Eight UDCA-treated patients with PBC with alkaline phosphatase ≥1.5 times the upper limit of normal range participated in a double-blind, placebo-controlled study. While continuing on UDCA, the patients were randomised to two 3-month crossover treatment periods with placebo and OCA, in random order, separated by a 1-month washout period without study treatment. After each of the two treatment periods, we determined rate constants for transport of conjugated bile acids between blood, hepatocytes, biliary canaliculi, and bile ducts by positron emission tomography of the liver using the conjugated bile acid tracer [N-methyl-11C]cholylsarcosine (11C-CSar). The hepatic blood perfusion was measured using infusion of indocyanine green and Fick's principle. RESULTS: Compared with placebo, OCA increased hepatic blood perfusion by a median of 11% (p = 0.045), the unidirectional uptake clearance of 11C-CSar from blood into hepatocytes by a median of 11% (p = 0.01), and the rate constant for secretion of 11C-CSar from hepatocytes into biliary canaliculi by a median of 73% (p = 0.03). This resulted in an OCA-induced decrease in the hepatocyte residence time of 11C-CSar by a median of 30% (p = 0.01), from group median 11 min to 8 min. CONCLUSIONS: This study of UDCA-treated patients with PBC showed that, compared with placebo, OCA increased the hepatic transport of the conjugated bile acid tracer 11C-CSar, and thus endogenous conjugated bile acids, from hepatocytes into biliary canaliculi. As a result, OCA reduced the time hepatocytes are exposed to potentially cytotoxic bile acids. LAY SUMMARY: Primary biliary cholangitis is a chronic liver disease in which the small bile ducts are progressively destroyed. We tested whether the treatment with obeticholic acid (OCA) would improve liver excretion of bile acids compared with placebo in 8 patients with primary biliary cholangitis. A special scanning technique (PET scan) showed that OCA increased the transport of bile acids from blood to bile. OCA thereby reduced the time that potentially toxic bile acids reside in the liver by approximately one-third.


Assuntos
Ácidos e Sais Biliares/metabolismo , Ductos Biliares Intra-Hepáticos , Ácido Quenodesoxicólico/análogos & derivados , Cirrose Hepática Biliar , Tomografia por Emissão de Pósitrons/métodos , Receptores Citoplasmáticos e Nucleares/agonistas , Idoso , Fosfatase Alcalina/sangue , Ductos Biliares Intra-Hepáticos/diagnóstico por imagem , Ductos Biliares Intra-Hepáticos/fisiopatologia , Transporte Biológico/efeitos dos fármacos , Ácido Quenodesoxicólico/administração & dosagem , Ácido Quenodesoxicólico/farmacocinética , Método Duplo-Cego , Feminino , Fármacos Gastrointestinais/administração & dosagem , Fármacos Gastrointestinais/farmacocinética , Fármacos Gastrointestinais/farmacologia , Hepatócitos/patologia , Humanos , Cirrose Hepática Biliar/diagnóstico , Cirrose Hepática Biliar/tratamento farmacológico , Cirrose Hepática Biliar/metabolismo , Pessoa de Meia-Idade , Resultado do Tratamento , Ácido Ursodesoxicólico/administração & dosagem , Ácido Ursodesoxicólico/farmacocinética
16.
N Engl J Med ; 378(17): 1593-1603, 2018 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-29694825

RESUMO

BACKGROUND: In a previous trial of antiretroviral therapy (ART) involving pregnant women with human immunodeficiency virus (HIV) infection, those randomly assigned to receive tenofovir, emtricitabine, and ritonavir-boosted lopinavir (TDF-FTC-LPV/r) had infants at greater risk for very premature birth and death within 14 days after delivery than those assigned to receive zidovudine, lamivudine, and ritonavir-boosted lopinavir (ZDV-3TC-LPV/r). METHODS: Using data from two U.S.-based cohort studies, we compared the risk of adverse birth outcomes among infants with in utero exposure to ZDV-3TC-LPV/r, TDF-FTC-LPV/r, or TDF-FTC with ritonavir-boosted atazanavir (ATV/r). We evaluated the risk of preterm birth (<37 completed weeks of gestation), very preterm birth (<34 completed weeks), low birth weight (<2500 g), and very low birth weight (<1500 g). Risk ratios with 95% confidence intervals were estimated with the use of modified Poisson models to adjust for confounding. RESULTS: There were 4646 birth outcomes. Few infants or fetuses were exposed to TDF-FTC-LPV/r (128 [2.8%]) as the initial ART regimen during gestation, in contrast with TDF-FTC-ATV/r (539 [11.6%]) and ZDV-3TC-LPV/r (954 [20.5%]). As compared with women receiving ZDV-3TC-LPV/r, women receiving TDF-FTC-LPV/r had a similar risk of preterm birth (risk ratio, 0.90; 95% confidence interval [CI], 0.60 to 1.33) and low birth weight (risk ratio, 1.13; 95% CI, 0.78 to 1.64). As compared to women receiving TDF-FTC-ATV/r, women receiving TDF-FTC-LPV/r had a similar or slightly higher risk of preterm birth (risk ratio, 1.14; 95% CI, 0.75 to 1.72) and low birth weight (risk ratio, 1.45; 95% CI, 0.96 to 2.17). There were no significant differences between regimens in the risk of very preterm birth or very low birth weight. CONCLUSIONS: The risk of adverse birth outcomes was not higher with TDF-FTC-LPV/r than with ZDV-3TC-LPV/r or TDF-FTC-ATV/r among HIV-infected women and their infants in the United States, although power was limited for some comparisons. (Funded by the National Institutes of Health and others.).


Assuntos
Fármacos Anti-HIV/uso terapêutico , Emtricitabina/uso terapêutico , Infecções por HIV/tratamento farmacológico , Recém-Nascido de Baixo Peso , Complicações Infecciosas na Gravidez/tratamento farmacológico , Resultado da Gravidez , Nascimento Prematuro/epidemiologia , Tenofovir/uso terapêutico , Adulto , Fármacos Anti-HIV/efeitos adversos , Estudos de Coortes , Transmissão de Doença Infecciosa/prevenção & controle , Esquema de Medicação , Quimioterapia Combinada/efeitos adversos , Emtricitabina/efeitos adversos , Feminino , Humanos , Recém-Nascido , Lamivudina/uso terapêutico , Lopinavir/efeitos adversos , Lopinavir/uso terapêutico , Gravidez , Risco , Ritonavir/uso terapêutico , Tenofovir/efeitos adversos , Zidovudina/uso terapêutico
17.
J Urban Health ; 98(5): 609-621, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-33929640

RESUMO

Over the past decade, large urban counties have implemented ShotSpotter, a gun fire detection technology, across the USA. It uses acoustic listening devices to identify discharged firearms' locations. We examined the effect of ShotSpotter with a pooled, cross-sectional time-series analysis within the 68 large metropolitan counties in the USA from 1999 to 2016. We identified ShotSpotter implementation years through publicly available media. We used a Poisson distribution to model the impact of ShotSpotter on firearm homicides, murder arrests, and weapons arrests. ShotSpotter did not display protective effects for all outcomes. Counties in states with permit-to-purchase firearm laws saw a 15% reduction in firearm homicide incidence rates; counties in states with right-to-carry laws saw a 21% increase in firearm homicide incidence rates. Results suggest that implementing ShotSpotter technology has no significant impact on firearm-related homicides or arrest outcomes. Policy solutions may represent a more cost-effective measure to reduce urban firearm violence.


Assuntos
Armas de Fogo , Suicídio , Estudos Transversais , Homicídio , Humanos , Tecnologia
18.
Inj Prev ; 27(1): 3-9, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33115707

RESUMO

INTRODUCTION: Understanding how the COVID-19 pandemic has impacted our health and safety is imperative. This study sought to examine the impact of COVID-19's stay-at-home order on daily vehicle miles travelled (VMT) and MVCs in Connecticut. METHODS: Using an interrupted time series design, we analysed daily VMT and MVCs stratified by crash severity and number of vehicles involved from 1 January to 30 April 2017, 2018, 2019 and 2020. MVC data were collected from the Connecticut Crash Data Repository; daily VMT estimates were obtained from StreetLight Insight's database. We used segmented Poisson regression models, controlling for daily temperature and daily precipitation. RESULTS: The mean daily VMT significantly decreased 43% in the post stay-at-home period in 2020. While the mean daily counts of crashes decreased in 2020 after the stay-at-home order was enacted, several types of crash rates increased after accounting for the VMT reductions. Single vehicle crash rates significantly increased 2.29 times, and specifically single vehicle fatal crash rates significantly increased 4.10 times when comparing the pre-stay-at-home and post-stay-at-home periods. DISCUSSION: Despite a decrease in the number of MVCs and VMT, the crash rate of single vehicles increased post stay-at-home order enactment in Connecticut after accounting for reductions in VMT.


Assuntos
Acidentes de Trânsito/estatística & dados numéricos , Condução de Veículo/estatística & dados numéricos , COVID-19/epidemiologia , Veículos Automotores/estatística & dados numéricos , Connecticut/epidemiologia , Humanos , Análise de Séries Temporais Interrompida , SARS-CoV-2 , Meios de Transporte/estatística & dados numéricos , Viagem/estatística & dados numéricos
19.
J Nematol ; 532021.
Artigo em Inglês | MEDLINE | ID: mdl-34286283

RESUMO

The goal was to determine the efficacy of entomopathogenic nematodes (EPNs) on Aethina tumida small hive beetle (SHB) in Alabama soils. The objectives were to (i) determine the pupation success of SHB wandering larvae; (ii) determine the efficacy of EPNs on SHB wandering larvae in natural and autoclaved soil; and (iii) determine the efficacy of EPNs on SHB wandering larvae in three Alabama soil types at typical low moisture levels. The Alabama soils were Kalmia loamy sand (KLS), Benndale fine sandy loam (BFSL), and Decatur silt loam (DSL). Heterorhabditis bacteriophora, H. indica, Steinernema carpocapsae, S. feltiae, S. kraussei, and S. riobrave were tested at population densities of 5, 10, 20, 40, and 80 third-stage infective EPN juveniles (IJ3) per 130 cm3 soil. Pupation success in SHB population densities of 5, 10, and 20 wandering larvae per Petri dish were similar. Of the six EPN species, S. carpocapsae achieved the highest efficacy across all EPN population densities in both natural and autoclaved soil. Steinernema riobrave and H. indica achieved the next highest efficacies; however, they were significantly less effective than S. carpocapsae. Steinernema carpocapsae parasitized 87% SHB wandering larvae across all population densities tested. Steinernema carpocapsae achieved the best efficacy colonizing 94% of the SHB in the KLS soil, 80% in the BFSL soil, and 47% in the DSL soil. In conclusions, S. carpocapsae is be a promising biological control EPN to implement into a management system on SHB.

20.
J Hepatol ; 73(1): 94-101, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32165251

RESUMO

BACKGROUND & AIMS: Primary sclerosing cholangitis (PSC) is a rare, cholestatic liver disease with no currently approved therapies. Obeticholic acid (OCA) is a potent farnesoid X receptor (FXR) agonist approved for the treatment of primary biliary cholangitis. We investigated the efficacy and safety of OCA in patients with PSC. METHODS: AESOP was a phase II, randomized, double-blind, placebo-controlled, dose-finding study. Eligible patients were 18 to 75 years of age with a diagnosis of PSC and serum alkaline phosphatase (ALP) ≥2× the upper limit of normal (ULN) and total bilirubin <2.5× ULN. Patients were randomized 1:1:1 to receive placebo, OCA 1.5-3.0 mg, or OCA 5-10 mg once daily for a 24-week, double-blind phase followed by a 2-year, long-term safety extension (LTSE). Primary endpoints were change in ALP from baseline to week 24, and safety. RESULTS: The intent-to-treat population comprised 76 patients randomized to placebo (n = 25), OCA 1.5-3.0 mg (n = 25), and OCA 5-10 mg (n = 26). At week 24, serum ALP was significantly reduced with OCA 5-10 mg vs. placebo (least-square [LS] mean difference = -83.4 [SE = 40.3] U/L; 95% CI -164.28 to -2.57; p = 0.043). Serum ALP was not significantly reduced with OCA 1.5-3.0 mg vs. placebo at week 24 (LS mean [SE] difference = -78.29 [41.81] U/L; 95% CI -162.08 to 5.50; p = 0.067). Total bilirubin remained comparable to baseline in all groups. The most common treatment-emergent adverse event was dose-related pruritus (placebo 46%; OCA 1.5-3.0 mg 60%; OCA 5-10 mg 67%). Reductions in ALP were maintained during the LTSE, and no new safety signals emerged. CONCLUSIONS: Treatment with OCA 5-10 mg reduced serum ALP in patients with PSC. Mild to moderate dose-related pruritus was the most common adverse event. REGISTRATION: ClinicalTrials.gov: NCT02177136; EudraCT: 2014-002205-38. LAY SUMMARY: Primary sclerosing cholangitis (PSC) is a long-term disease that damages the bile ducts in the liver over time. In the AESOP clinical study in patients with PSC, obeticholic acid reduced serum alkaline phosphatase (a potential marker of disease severity) during an initial 24-week treatment period. The result was sustained during the 2-year, long-term extension of the study. The most common side effect of obeticholic acid in the study was itchy skin, which is consistent with earlier clinical studies.


Assuntos
Fosfatase Alcalina/sangue , Ácido Quenodesoxicólico/análogos & derivados , Cirrose Hepática Biliar , Prurido , Ácido Quenodesoxicólico/administração & dosagem , Ácido Quenodesoxicólico/efeitos adversos , Colagogos e Coleréticos/administração & dosagem , Colagogos e Coleréticos/efeitos adversos , Relação Dose-Resposta a Droga , Método Duplo-Cego , Monitoramento de Medicamentos/métodos , Feminino , Humanos , Cirrose Hepática Biliar/sangue , Cirrose Hepática Biliar/diagnóstico , Cirrose Hepática Biliar/tratamento farmacológico , Testes de Função Hepática/métodos , Masculino , Pessoa de Meia-Idade , Prurido/induzido quimicamente , Prurido/diagnóstico , Resultado do Tratamento
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