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1.
N Engl J Med ; 386(18): 1700-1711, 2022 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-35353960

RESUMO

BACKGROUND: Polyclonal convalescent plasma may be obtained from donors who have recovered from coronavirus disease 2019 (Covid-19). The efficacy of this plasma in preventing serious complications in outpatients with recent-onset Covid-19 is uncertain. METHODS: In this multicenter, double-blind, randomized, controlled trial, we evaluated the efficacy and safety of Covid-19 convalescent plasma, as compared with control plasma, in symptomatic adults (≥18 years of age) who had tested positive for severe acute respiratory syndrome coronavirus 2, regardless of their risk factors for disease progression or vaccination status. Participants were enrolled within 8 days after symptom onset and received a transfusion within 1 day after randomization. The primary outcome was Covid-19-related hospitalization within 28 days after transfusion. RESULTS: Participants were enrolled from June 3, 2020, through October 1, 2021. A total of 1225 participants underwent randomization, and 1181 received a transfusion. In the prespecified modified intention-to-treat analysis that included only participants who received a transfusion, the primary outcome occurred in 17 of 592 participants (2.9%) who received convalescent plasma and 37 of 589 participants (6.3%) who received control plasma (absolute risk reduction, 3.4 percentage points; 95% confidence interval, 1.0 to 5.8; P = 0.005), which corresponded to a relative risk reduction of 54%. Evidence of efficacy in vaccinated participants cannot be inferred from these data because 53 of the 54 participants with Covid-19 who were hospitalized were unvaccinated and 1 participant was partially vaccinated. A total of 16 grade 3 or 4 adverse events (7 in the convalescent-plasma group and 9 in the control-plasma group) occurred in participants who were not hospitalized. CONCLUSIONS: In participants with Covid-19, most of whom were unvaccinated, the administration of convalescent plasma within 9 days after the onset of symptoms reduced the risk of disease progression leading to hospitalization. (Funded by the Department of Defense and others; CSSC-004 ClinicalTrials.gov number, NCT04373460.).


Assuntos
COVID-19 , Imunização Passiva , Adulto , Assistência Ambulatorial , COVID-19/terapia , Progressão da Doença , Método Duplo-Cego , Hospitalização , Humanos , Imunização Passiva/efeitos adversos , Imunização Passiva/métodos , Resultado do Tratamento , Estados Unidos , Soroterapia para COVID-19
2.
J Emerg Med ; 67(1): e99-e104, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38797612

RESUMO

BACKGROUND: The changing hospital business model has raised ethical issues for emergency physicians (EPs) in a healthcare system that often prioritizes profits over patient welfare. For-profit hospitals, driven by profit motives, may prioritize treating patients with lucrative insurance plans and those who can afford expensive treatments. Private equity investors, who now own many for-profit hospitals, focus on short-term financial gains, leading to cost-cutting measures and pressure on EPs to prioritize financial goals over patient welfare. Nonprofit hospitals, mandated to provide charity care to the underserved, may fail to meet their community service obligations, resulting in disparities in healthcare access. OBJECTIVE: This review examines the ethical challenges faced by emergency physicians (EPs) in response to the evolving hospital business model, which increasingly prioritizes profits over patient welfare. DISCUSSION: Emergency physicians face ethical dilemmas in this changing environment, including conflicts between patient care and financial interests. Upholding professional ethics and the principle of beneficence is essential. Another challenge is equitable access to healthcare, with some nonprofit hospitals reducing charity care, thus exacerbating disparities. EPs must uphold the ethical principle of justice, ensuring quality care for all patients, regardless of financial means. Conflicts of interest may arise when EPs work in hospitals owned by private equity firms or with affiliations with pharmaceutical companies or medical device manufacturers, potentially compromising patient care. CONCLUSION: Emergency physicians must navigate these ethical issues while upholding professional ethics and advocating for patients' best interests. Collaboration with hospital administrators, policymakers, and stakeholders is vital to address these concerns and prioritize patient welfare in healthcare delivery.


Assuntos
Serviço Hospitalar de Emergência , Humanos , Serviço Hospitalar de Emergência/ética , Serviço Hospitalar de Emergência/organização & administração , Serviço Hospitalar de Emergência/economia , Medicina de Emergência/ética , Médicos/ética , Conflito de Interesses , Acessibilidade aos Serviços de Saúde/ética , Modelos Organizacionais
3.
J Infect Dis ; 227(11): 1266-1273, 2023 05 29.
Artigo em Inglês | MEDLINE | ID: mdl-36722044

RESUMO

BACKGROUND: Coronavirus disease 2019 (COVID-19) convalescent plasma (CCP) reduces hospitalizations among outpatients treated early after symptom onset. It is unknown whether CCP reduces time to symptom resolution among outpatients. METHODS: We evaluated symptom resolution at day 14 by trial arm using an adjusted subdistribution hazard model, with hospitalization as a competing risk. We also assessed the prevalence of symptom clusters at day 14 between treatments. Clusters were defined based on biologic clustering, impact on ability to work, and an algorithm. RESULTS: Among 1070 outpatients followed up after transfusion, 381 of 538 (70.8%) receiving CCP and 381 of 532 (71.6%) receiving control plasma were still symptomatic (P = .78) at day 14. Associations between CCP and symptom resolution by day 14 did not differ significantly from those in controls after adjustment for baseline characteristics (adjusted subdistribution hazard ratio, 0.99; P = .62). The most common cluster consisted of cough, fatigue, shortness of breath, and headache and was found in 308 (57.2%) and 325 (61.1%) of CCP and control plasma recipients, respectively (P = .16). CONCLUSIONS: In this trial of outpatients with early COVID-19, CCP was not associated with faster resolution of symptoms compared with control. Overall, there were no differences by treatment in the prevalence of each symptom or symptom clusters at day 14. CLINICAL TRIALS REGISTRATION: NCT04373460.


Assuntos
COVID-19 , Humanos , COVID-19/terapia , SARS-CoV-2 , Pacientes Ambulatoriais , Síndrome , Imunização Passiva/efeitos adversos , Soroterapia para COVID-19
4.
Clin Infect Dis ; 76(12): 2077-2086, 2023 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-36809473

RESUMO

BACKGROUND: Outpatient monoclonal antibodies are no longer effective and antiviral treatments for coronavirus disease 2019 (COVID-19) disease remain largely unavailable in many countries worldwide. Although treatment with COVID-19 convalescent plasma (CCP) is promising, clinical trials among outpatients have shown mixed results. METHODS: We conducted an individual participant data meta-analysis from outpatient trials to assess the overall risk reduction for all-cause hospitalizations by day 28 in transfused participants. Relevant trials were identified by searching Medline, Embase, medRxiv, World Health Organization COVID-19 Research Database, Cochrane Library, and Web of Science from January 2020 to September 2022. RESULTS: Five included studies from 4 countries enrolled and transfused 2620 adult patients. Comorbidities were present in 1795 (69%). The virus neutralizing antibody dilutional titer levels ranged from 8 to 14 580 in diverse assays. One hundred sixty of 1315 (12.2%) control patients were hospitalized, versus 111 of 1305 (8.5%) CCP-treated patients, yielding a 3.7% (95% confidence interval [CI], 1.3%-6.0%; P = .001) absolute risk reduction and 30.1% relative risk reduction for all-cause hospitalization. The hospitalization reduction was greatest in those with both early transfusion and high titer with a 7.6% absolute risk reduction (95% CI, 4.0%-11.1%; P = .0001) accompanied by at 51.4% relative risk reduction. No significant reduction in hospitalization was seen with treatment >5 days after symptom onset or in those receiving CCP with antibody titers below the median titer. CONCLUSIONS: Among outpatients with COVID-19, treatment with CCP reduced the rate of all-cause hospitalization and may be most effective when given within 5 days of symptom onset and when antibody titer is higher.


Assuntos
COVID-19 , Adulto , Humanos , COVID-19/terapia , Pacientes Ambulatoriais , SARS-CoV-2 , Soroterapia para COVID-19 , Ensaios Clínicos Controlados Aleatórios como Assunto , Hospitalização
5.
Clin Infect Dis ; 76(3): e477-e486, 2023 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-35579509

RESUMO

BACKGROUND: The efficacy of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) convalescent plasma (CCP) for preventing infection in exposed, uninfected individuals is unknown. CCP might prevent infection when administered before symptoms or laboratory evidence of infection. METHODS: This double-blinded, phase 2 randomized, controlled trial (RCT) compared the efficacy and safety of prophylactic high titer (≥1:320 by Euroimmun ELISA) CCP with standard plasma. Asymptomatic participants aged ≥18 years with close contact exposure to a person with confirmed coronavirus disease 2019 (COVID-19) in the previous 120 hours and negative SARS-CoV-2 test within 24 hours before transfusion were eligible. The primary outcome was new SARS-CoV-2 infection. RESULTS: In total, 180 participants were enrolled; 87 were assigned to CCP and 93 to control plasma, and 170 transfused at 19 sites across the United States from June 2020 to March 2021. Two were excluded for screening SARS-CoV-2 reverse transcription polymerase chain reaction (RT-PCR) positivity. Of the remaining 168 participants, 12/81 (14.8%) CCP and 13/87 (14.9%) control recipients developed SARS-CoV-2 infection; 6 (7.4%) CCP and 7 (8%) control recipients developed COVID-19 (infection with symptoms). There were no COVID-19-related hospitalizations in CCP and 2 in control recipients. Efficacy by restricted mean infection free time (RMIFT) by 28 days for all SARS-CoV-2 infections (25.3 vs 25.2 days; P = .49) and COVID-19 (26.3 vs 25.9 days; P = .35) was similar for both groups. CONCLUSIONS: Administration of high-titer CCP as post-exposure prophylaxis, although appearing safe, did not prevent SARS-CoV-2 infection. CLINICAL TRIALS REGISTRATION: NCT04323800.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , Adolescente , Adulto , COVID-19/prevenção & controle , Profilaxia Pós-Exposição , Soroterapia para COVID-19 , Método Duplo-Cego , Imunização Passiva
6.
Transfusion ; 63(9): 1639-1648, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37534607

RESUMO

BACKGROUND: COVID-19 convalescent plasma (CCP) is an important therapeutic option for outpatients at high risk of hospitalization from SARS-CoV-2 infection. We assessed the safety of outpatient CCP transfusions administered during clinical trials. STUDY DESIGN AND METHODS: We analyzed data pertaining to transfusion-related reactions from two randomized controlled trials in the U.S. that evaluated the efficacy of CCP versus control plasma in various ambulatory settings. Multivariable logistic regression was used to assess whether CCP was associated with transfusion reactions, after adjusting for potential confounders. RESULTS: The combined study reported 79/1351 (5.9%) adverse events during the transfusion visit, with the majority 62/1351 (4.6%) characterized by mild, allergic-type findings of urticaria, and/or pruritus consistent with minor allergic transfusion reactions; the other reported events were attributed to the patients' underlying disease, COVID-19, or vasovagal in nature. We found no difference in the likelihood of allergic transfusion reactions between those receiving CCP versus control plasma (adjusted odds ratio [AOR], 0.75; 95% CI, 0.43-1.31). Risk of urticaria and/or pruritus increased with a pre-existing diagnosis of asthma (AOR, 2.33; 95% CI, 1.16-4.67). We did not observe any CCP-attributed antibody disease enhancement in participants with COVID-19 or increased risk of infection. There were no life-threatening severe transfusion reactions and no patients required hospitalization related to transfusion-associated complications. DISCUSSION: Outpatient plasma administration was safely performed for nearly 1400 participants. CCP is a safe therapeutic option for outpatients at risk of hospitalization from COVID-19.


Assuntos
COVID-19 , Reação Transfusional , Urticária , Humanos , COVID-19/terapia , COVID-19/etiologia , Soroterapia para COVID-19 , Imunização Passiva/efeitos adversos , Pacientes Ambulatoriais , SARS-CoV-2 , Reação Transfusional/etiologia , Urticária/etiologia , Ensaios Clínicos Controlados Aleatórios como Assunto
7.
Prehosp Emerg Care ; 27(8): 1054-1057, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36318902

RESUMO

INTRODUCTION: High-quality data are important to understanding racial differences in outcome following out of hospital cardiac arrest (OHCA). Previous studies have shown differences in OHCA outcomes according to both race and socioeconomic status. EMS reporting of data on race is often incomplete. We aim to determine the effect of missing data on the determination of racial differences in outcomes for OHCA patients. METHODS: We performed a secondary analysis of a data set developed by probabilistically linking the Michigan Cardiac Arrest Registry to Enhance Survival (CARES) and the Michigan Inpatient Database (MIDB). Adult OHCA patients (age >18) who survived to hospital admission between 2014 and 2017 were included. Both datasets recorded patient race and ethnicity with CARES using a single race/ethnicity variable. Patients were categorized as White, Black, other, or missing and only a single choice was allowed. Due to the small number of Hispanic patients and the combined race/ethnicity variable, these patients were excluded. The outcomes of interest were survival to hospital discharge and survival to discharge with Cerebral Performance Category 1 or 2 (good outcome). Outcomes were stratified according to EMS- or hospital-documented race. RESULTS: We included 3,756 matched patients, after excluding 34 Hispanic patients from analysis. Documentation of patient race was missing in 892 (22.1%) of CARES and 212 (5.6%) of MIDB patients. When both datasets documented Black or White race, agreement in race documentation was excellent (κ=0.83). White patients were more likely to have good outcomes than Black in both the CARES (27.3% vs 14.8%) and MIDB (26.9% vs 16.1%) databases (both p < 0.001), but were not more likely to survive (30.8% vs 27.3% p = 0.22; 30.3% vs 28.1%, p = 0.07). Moreover, we found no significant difference in outcome measures based on race documentation for White vs Black patients (good outcome [27.3 vs 26.9% (MIDB)] and [16.1% vs 14.8% (CARES)] respectively and survival [30.8% vs 30.3% (MIDB)] and [27.3 vs 28.1% (CARES)] respectively). CONCLUSION: Despite higher rates of missing EMS documentation, we identified statistically similar rates in OHCA outcome measures between databases. Further work is needed to determine the true effect of missing documentation of race on OHCA outcome measures.


Assuntos
Reanimação Cardiopulmonar , Serviços Médicos de Emergência , Parada Cardíaca Extra-Hospitalar , Adulto , Humanos , Hospitais , Etnicidade
8.
Transfusion ; 62(5): 933-941, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35352362

RESUMO

Convalescent plasma, collected from donors who have recovered from a pathogen of interest, has been used to treat infectious diseases, particularly in times of outbreak, when alternative therapies were unavailable. The COVID-19 pandemic revived interest in the use of convalescent plasma. Large observational studies and clinical trials that were executed during the pandemic provided insight into how to use convalescent plasma, whereby high levels of antibodies against the pathogen of interest and administration early within the time course of the disease are critical for optimal therapeutic effect. Several studies have shown outpatient administration of COVID-19 convalescent plasma (CCP) to be both safe and effective, preventing clinical progression in patients when administered within the first week of COVID-19. The United States Food and Drug Administration expanded its emergency use authorization (EUA) to allow for the administration of CCP in an outpatient setting in December 2021, at least for immunocompromised patients or those on immunosuppressive therapy. Outpatient transfusion of CCP and infusion of monoclonal antibody therapies for a highly transmissible infectious disease introduces nuanced challenges related to infection prevention. Drawing on our experiences with the clinical and research use of CCP, we describe the logistical considerations and workflow spanning procurement of qualified products, infrastructure, staffing, transfusion, and associated management of adverse events. The purpose of this description is to facilitate the efforts of others intent on establishing outpatient transfusion programs for CCP and other antibody-based therapies.


Assuntos
COVID-19 , COVID-19/terapia , Humanos , Imunização Passiva , Pacientes Ambulatoriais , Pandemias , SARS-CoV-2 , Estados Unidos , Soroterapia para COVID-19
9.
J Emerg Med ; 62(2): 182-190, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34963516

RESUMO

BACKGROUND: The recent proliferation of electric standing scooters in major urban areas of the United States has been accompanied by injuries of varying severity and nature, representing a growing public health concern. OBJECTIVE: Our aim was to characterize imaging utilization patterns for injuries associated with electric scooter (e-scooter) use, including their initial emergency department (ED) management. METHODS: We conducted a retrospective review of the electronic medical record for all patients presenting to affiliated EDs for e-scooter-related injuries between July 2018 and April 2020. Demographics, date and time of presentation, imaging study type, resultant injury, and procedural details were recorded. RESULTS: Ninety-seven patients were included; mean age was 27.6 years. Of these, 55 patients (57%) had injuries identified on imaging and 40% of all imaging studies were positive. Most identified injuries (61%) were musculoskeletal, with a small number of neurological (2%) and genitourinary (1%) injuries. The highest prevalence of presentations occurred in August; most patients (72%) presented between 3 pm and 1 am and granular peaks were between 12 am and 1 am and 5 pm and 6 pm. CONCLUSIONS: Patients presenting with e-scooter injuries have a high likelihood of injury to the radial head, nasal bone, and malleoli. Emergency physicians should be especially vigilant for injuries in these areas at presentation. Visceral injuries are uncommon but may be severe enough to warrant surgery.


Assuntos
Traumatismos por Eletricidade , Serviço Hospitalar de Emergência , Adulto , Diagnóstico por Imagem , Traumatismos por Eletricidade/epidemiologia , Traumatismos por Eletricidade/etiologia , Registros Eletrônicos de Saúde , Humanos , Estudos Retrospectivos , Estados Unidos
10.
Pharm Res ; 38(7): 1209-1219, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34189639

RESUMO

PURPOSE: PEGylated pH-sensitive liposomes (PSL) dual-loaded with gemcitabine and curcumin were investigated for the potential application in gemcitabine-resistant pancreatic ductal adenocarcinoma (PDAC) treatment. Curcumin was employed as an inhibitor of the efflux transporter, multidrug resistance protein 5 (MRP5) in PDAC cells. METHODS: Liposomes were prepared with gemcitabine in the core and curcumin in the bilayers. The effects of curcumin on pH-sensitivity and 'endosome escape' of PSL with different PEGylation were investigated using a calcein self-quench assay. The effects of curcumin on intracellular gemcitabine concentrations, and cytotoxicity to a MIA PaCa-2 PDAC cell line was evaluated. The pharmacokinetics were investigated in rats following intravenous injection. RESULTS: The addition of curcumin to the PSL bilayers (0.2-1 mol%)slightly decreased the pH-sensitivity of PSL, but to a less extent than PEGylation (0-5 mol%). Co-treatment with curcumin increased gemcitabine cellular accumulation in a concentration-dependent manner, and resulted in synergistic cytotoxicity towards MIA PaCa-2cells.Both these effects were augmented by the use of PSL, particularly when the two drugs were co-loaded in PSL. In rats, the dual-drug loaded PSL produced significantly reduced (p < 0.05) plasma clearance (CL) and volume of distribution (Vd) for both drugs, alongside 3 to 4-fold increases in the area-under-the-concentration-time curves compared to the free drugs. Additionally, curcumin slightly increase the plasma concentrations of gemcitabine possibly also via the MRP5 inhibition effect. CONCLUSION: Co-delivery of curcumin with gemcitabine using PSL not only increased the intracellular gemcitabine concentration thus cytotoxicity to MIA PaCa-2 cells but also significantly improved the pharmacokinetic profiles for both drugs. Graphical Abstract.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Carcinoma Ductal Pancreático/tratamento farmacológico , Curcumina/farmacologia , Desoxicitidina/análogos & derivados , Neoplasias Pancreáticas/tratamento farmacológico , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Área Sob a Curva , Carcinoma Ductal Pancreático/patologia , Linhagem Celular Tumoral , Curcumina/uso terapêutico , Desoxicitidina/farmacologia , Desoxicitidina/uso terapêutico , Liberação Controlada de Fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Sinergismo Farmacológico , Humanos , Concentração de Íons de Hidrogênio , Lipossomos , Masculino , Proteínas Associadas à Resistência a Múltiplos Medicamentos/antagonistas & inibidores , Proteínas Associadas à Resistência a Múltiplos Medicamentos/metabolismo , Neoplasias Pancreáticas/patologia , Polietilenoglicóis/química , Ratos , Gencitabina
11.
Am J Emerg Med ; 36(4): 560-566, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28967450

RESUMO

STUDY OBJECTIVE: Quantify the correlation between blood pressure variability (BPV) and markers of illness severity: serum lactate (LAC) or Sequential Organ Failure Assessment (SOFA) scores. METHODS: We performed a secondary analysis of data from a prospective, observational study evaluating fluid resuscitation on adult, septic, ED patients. Vital signs and fluid infusion volumes were recorded every 15min during the 3h following ED arrival. BPV was assessed via average real variability (ARV): the average of the absolute differences between consecutive BP measurements. ARV was calculated for the time periods before and after 3 fluid infusion milestones: 10-, 20-, and 30-mL/kg total body weight (TBW). Spearman's rho correlation coefficient analysis was utilized. A p-value<0.05 was considered statistically significant. RESULTS: Forty patients were included. Mean fluid infusion was 33.7mL/kg TBW (SD 22.1). All patients received fluid infusion≥10mL/kg TBW, 25 patients received fluid infusion>20mL/kg TBW, and 16 patients received fluid infusion>30mL/kg TBW. Mean initial LAC was 4.0mmol/L (SD 3.2). Mean repeat LAC was 3.1mmol/L (SD 3.2), obtained an average of 6.6h (SD 5.3) later. Mean SOFA score was 7.0 (SD 4.4). BPV correlated with both follow-up LAC (r=0.564; p=0.023) and SOFA score (r=0.544; p=0.024) among the cohort that received a fluid infusion>20-mL/kg TBW. CONCLUSION: With the finding of a positive correlation between BPV and markers of illness severity (LAC and SOFA scores), this pilot study introduces BPV analysis as a real-time, non-invasive tool for continuous sepsis monitoring in the ED.


Assuntos
Pressão Sanguínea , Hidratação , Sepse/diagnóstico , Sepse/fisiopatologia , Sepse/terapia , Adulto , Idoso , Determinação da Pressão Arterial , Serviço Hospitalar de Emergência , Feminino , Humanos , Ácido Láctico/sangue , Masculino , Pessoa de Meia-Idade , Monitorização Fisiológica , Escores de Disfunção Orgânica , Projetos Piloto , Estudos Prospectivos
12.
Pharm Res ; 33(7): 1628-37, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-26964546

RESUMO

PURPOSES: To develop pH-sensitive liposomes (PSL) containing a high content of gemcitabine; and to investigate whether drug loading (DL) would alter the in vitro and pharmacokinetic properties. METHODS: PSL with a high DL were obtained using a modified small-volume incubation method. The DL effects on drug release rate and in vitro cytotoxicity of PSL were evaluated using MIA PaCa-2 pancreatic cancer cells and their pharmacokinetics investigated in rats. RESULTS: The highest DL of 4.5 ± 0.1% was achieved for gemcitabine in PSL with 145 ± 5 nm diameter. DL did not alter the in vitro release rate from PSL. The IC50 (48 h) of PSL (DL 0.5 and 4.5%) and non pH-sensitive liposomes (NPSL, DL 4.2%) were 1.1 ± 0.1, 0.7 ± 0.1 and 37.0 ± 7.5 µM, respectively. The PSL resulted in a 4.2-fold increase in its elimination half-life (6.2 h) compared to gemcitabine solution (1.4 h) in rats. No significant difference in pharmacokinetic parameters was observed between the two PSL (DL 0.5 and 4.5%). CONCLUSION: The PSL offered advantages over NPSL in restoring the sensitivity of pancreatic cancer cells to gemcitabine without requiring a high DL. DL in the PSL did not alter release rate, cytotoxicity or their long-circulating properties. Graphical Abstract ᅟ.


Assuntos
Desoxicitidina/análogos & derivados , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Lipossomos/química , Lipossomos/farmacologia , Pâncreas/efeitos dos fármacos , Neoplasias Pancreáticas/tratamento farmacológico , Animais , Linhagem Celular Tumoral , Desoxicitidina/química , Desoxicitidina/farmacologia , Liberação Controlada de Fármacos/fisiologia , Meia-Vida , Concentração de Íons de Hidrogênio , Tamanho da Partícula , Soluções Farmacêuticas/química , Soluções Farmacêuticas/farmacologia , Ratos , Ratos Sprague-Dawley , Gencitabina
13.
Pharm Res ; 32(7): 2428-38, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25663325

RESUMO

PURPOSE: The in vitro and in vivo properties of PEGylated pH-sensitive liposomes (PSL) prepared by pre- and post-insertion techniques were investigated. METHODS: A pre-insertion or post-insertion technique was used for PSL PEGylation. For the first time, confocal laser scanning microscopy coupled with a modified calcein self-quench assay was applied to evaluate the endosome escape capability. PSL cellular uptake was evaluated using macrophages and the cytotoxicity using a gemcitabine (model drug)-resistant MIA PaCa-2 cells. The pharmacokinetics of PSL encapsulated gemcitabine was investigated in rats. RESULTS: PEGylation reduced the pH-sensitivity in a concentration-dependent manner (0.5-5% mol). Both PEGylation methods reduced the uptake of PSL by macrophages by over 60%. Cytotoxicity was ranked in the order: post-inserted PSL ≥ pre-inserted PSL > non-PSL > gemcitabine solution, consistent with the confocal microscopic observation and pH-sensitivity. Both pre and post-inserted PSL resulted in significant reductions (p < 0.05) in plasma clearance (58.6 and 38.4 ml/h/kg), increases in the area-under-the-concentration-time curve (56.9 and 87.1 µM · h) and half-life (6.1 and 6.2 h) compared to gemcitabine solution (152.9 ml/h/kg, 22.2 µM · h and 1.4 h). CONCLUSION: PEGylation by post-insertion offers advantages over pre-insertion to obtain PSL with enhanced pH-sensitivity, more effective intra-cytoplasmic delivery, and a superior pharmacokinetics.


Assuntos
Antimetabólitos Antineoplásicos/farmacologia , Desoxicitidina/análogos & derivados , Portadores de Fármacos/química , Polietilenoglicóis/química , Animais , Antimetabólitos Antineoplásicos/administração & dosagem , Antimetabólitos Antineoplásicos/sangue , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Desoxicitidina/administração & dosagem , Desoxicitidina/sangue , Desoxicitidina/farmacologia , Relação Dose-Resposta a Droga , Composição de Medicamentos , Liberação Controlada de Fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Endocitose/efeitos dos fármacos , Endossomos/metabolismo , Humanos , Concentração de Íons de Hidrogênio , Lipossomos , Macrófagos/metabolismo , Tamanho da Partícula , Ratos Sprague-Dawley , Propriedades de Superfície , Gencitabina
14.
Pharm Res ; 31(10): 2583-92, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24639234

RESUMO

PURPOSE: The objective of this study was to develop high-content gemcitabine PEGylated liposomes to reverse gemcitabine resistance in pancreatic tumour cells. The mechanism of drug loading into liposomes was also investigated. METHODS: To increase the drug entrapment efficiency (EE) and drug loading (DL), a novel passive loading approach named Small Volume Incubation method (SVI) was developed and compared to the reverse phase evaporation (REV) and remote loading methods. The in vitro cytotoxicity was evaluated using MIA PaCa-2 and Panc-1 cell lines. RESULTS: The EE for remote loading was 12.3 ± 0.3%, much lower than expected and a burst release was observed with the resultant liposomes. Using the optimized SVI method, increased EE (37 ± 1%) and DL (4%, w/w) were obtained. The liposomes (200 ± 5 nm) showed minimal drug leakage, good stability, and significant improvement in cytotoxicity to the gemcitabine-resistant pancreatic cancer cell lines. CONCLUSIONS: Remote loading was not suitable for loading gemcitabine into liposomes. pKa > 4.6 for basic drugs and intra-liposomal precipitation of loaded compounds were suggested as an additional requirement to the current criteria for remote loading using ammonium sulphate gradient (pKa < 11). High DL is essential for liposomes to reverse gemcitabine resistance in pancreatic cell lines.


Assuntos
Antimetabólitos Antineoplásicos/administração & dosagem , Desoxicitidina/análogos & derivados , Portadores de Fármacos/química , Neoplasias Pancreáticas/patologia , Polietilenoglicóis/química , Tecnologia Farmacêutica/métodos , Antimetabólitos Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Desoxicitidina/administração & dosagem , Desoxicitidina/farmacologia , Composição de Medicamentos , Liberação Controlada de Fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Estabilidade de Medicamentos , Humanos , Lipossomos , Tamanho da Partícula , Propriedades de Superfície , Gencitabina
15.
Acad Emerg Med ; 2024 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-38643419

RESUMO

BACKGROUND: Large-vessel occlusion (LVO) stroke represents one-third of acute ischemic stroke (AIS) in the United States but causes two-thirds of poststroke dependence and >90% of poststroke mortality. Prehospital LVO stroke detection permits efficient emergency medical systems (EMS) transport to an endovascular thrombectomy (EVT)-capable center. Our primary objective was to determine the feasibility of using a cranial accelerometry (CA) headset device for prehospital LVO stroke detection. Our secondary objective was development of an algorithm capable of distinguishing LVO stroke from other conditions. METHODS: We prospectively enrolled consecutive adult patients suspected of acute stroke from 11 study hospitals in four different U.S. geographical regions over a 21-month period. Patients received device placement by prehospital EMS personnel. Headset data were matched with clinical data following informed consent. LVO stroke diagnosis was determined by medical chart review. The device was trained using device data and Los Angeles Motor Scale (LAMS) examination components. A binary threshold was selected for comparison of device performance to LAMS scores. RESULTS: A total of 594 subjects were enrolled, including 183 subjects who received the second-generation device. Usable data were captured in 158 patients (86.3%). Study subjects were 53% female and 56% Black/African American, with median age 69 years. Twenty-six (16.4%) patients had LVO and 132 (83.6%) were not LVO (not-LVO AIS, 33; intracerebral hemorrhage, nine; stroke mimics, 90). COVID-19 testing and positivity rates (10.6%) were not different between groups. We found a sensitivity of 38.5% and specificity of 82.7% for LAMS ≥ 4 in detecting LVO stroke versus a sensitivity of 84.6% (p < 0.0015 for superiority) and specificity of 82.6% (p = 0.81 for superiority) for the device algorithm (CA + LAMS). CONCLUSIONS: Obtaining adequate recordings with a CA headset is highly feasible in the prehospital environment. Use of the device algorithm incorporating both CA and LAMS data for LVO detection resulted in significantly higher sensitivity without reduced specificity when compared to the use of LAMS alone.

16.
Microbiol Spectr ; 12(1): e0328623, 2024 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-38009954

RESUMO

IMPORTANCE: This study examined the role that cytokines may have played in the beneficial outcomes found when outpatient individuals infected with SARS-CoV-2 were transfused with COVID-19 convalescent plasma (CCP) early in their infection. We found that the pro-inflammatory cytokine IL-6 decreased significantly faster in patients treated early with CCP. Participants with COVID-19 treated with CCP later in the infection did not have the same effect. This decrease in IL-6 levels after early CCP treatment suggests a possible role of inflammation in COVID-19 progression. The evidence of IL-6 involvement brings insight into the possible mechanisms involved in CCP treatment mitigating SARS-CoV-2 severity.


Assuntos
COVID-19 , Humanos , COVID-19/terapia , Soroterapia para COVID-19 , Interleucina-6 , SARS-CoV-2 , Citocinas , Imunização Passiva
17.
Res Sq ; 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38947064

RESUMO

Background: Cardiac arrest is a common and devastating emergency of both the heart and brain. More than 380,000 patients suffer out-of-hospital cardiac arrest annually in the United States. Induced cooling of comatose patients markedly improved neurological and functional outcomes in pivotal randomized clinical trials, but the optimal duration of therapeutic hypothermia has not yet been established. Methods: This study is a multi-center randomized, response-adaptive, duration (dose) finding, comparative effectiveness clinical trial with blinded outcome assessment. We investigate two populations of adult comatose survivors of cardiac arrest to ascertain the shortest duration of cooling that provides the maximum treatment effect. The design is based on a statistical model of response as defined by the primary endpoint, a weighted 90-day mRS (modified Rankin Scale, a measure of neurologic disability), across the treatment arms. Subjects will initially be equally randomized between 12, 24, and 48 hours of therapeutic cooling. After the first 200 subjects have been randomized, additional treatment arms between 12 and 48 hours will be opened and patients will be allocated, within each initial cardiac rhythm type (shockable or non-shockable), by response adaptive randomization. As the trial continues, shorter and longer duration arms may be opened. A maximum sample size of 1800 subjects is proposed. Secondary objectives are to characterize: the overall safety and adverse events associated with duration of cooling, the effect on neuropsychological outcomes, and the effect on patient reported quality of life measures. Discussion: In-vitro and in-vivo studies have shown the neuroprotective effects of therapeutic hypothermia for cardiac arrest. We hypothesize that longer durations of cooling may improve either the proportion of patients that attain a good neurological recovery or may result in better recovery among the proportion already categorized as having a good outcome. If the treatment effect of cooling is increasing across duration, for at least some set of durations, then this provides evidence of the efficacy of cooling itself versus normothermia, even in the absence of a normothermia control arm, confirming previous RCTs for OHCA survivors of shockable rhythms and provides the first prospective controlled evidence of efficacy in those without initial shockable rhythms. Trial registration: ClinicalTrials.gov (NCT04217551, 2019-12-30).

18.
JCI Insight ; 9(8)2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38483534

RESUMO

BACKGROUNDCOVID-19 convalescent plasma (CCP) virus-specific antibody levels that translate into recipient posttransfusion antibody levels sufficient to prevent disease progression are not defined.METHODSThis secondary analysis correlated donor and recipient antibody levels to hospitalization risk among unvaccinated, seronegative CCP recipients within the outpatient, double-blind, randomized clinical trial that compared CCP to control plasma. The majority of COVID-19 CCP arm hospitalizations (15/17, 88%) occurred in this unvaccinated, seronegative subgroup. A functional cutoff to delineate recipient high versus low posttransfusion antibody levels was established by 2 methods: (i) analyzing virus neutralization-equivalent anti-Spike receptor-binding domain immunoglobulin G (anti-S-RBD IgG) responses in donors or (ii) receiver operating characteristic (ROC) curve analysis.RESULTSSARS-CoV-2 anti-S-RBD IgG antibody was volume diluted 21.3-fold into posttransfusion seronegative recipients from matched donor units. Virus-specific antibody delivered was approximately 1.2 mg. The high-antibody recipients transfused early (symptom onset within 5 days) had no hospitalizations. A CCP-recipient analysis for antibody thresholds correlated to reduced hospitalizations found a statistical significant association between early transfusion and high antibodies versus all other CCP recipients (or control plasma), with antibody cutoffs established by both methods-donor-based virus neutralization cutoffs in posttransfusion recipients (0/85 [0%] versus 15/276 [5.6%]; P = 0.03) or ROC-based cutoff (0/94 [0%] versus 15/267 [5.4%]; P = 0.01).CONCLUSIONIn unvaccinated, seronegative CCP recipients, early transfusion of plasma units in the upper 30% of study donors' antibody levels reduced outpatient hospitalizations. High antibody level plasma units, given early, should be reserved for therapeutic use.TRIAL REGISTRATIONClinicalTrials.gov NCT04373460.FUNDINGDepartment of Defense (W911QY2090012); Defense Health Agency; Bloomberg Philanthropies; the State of Maryland; NIH (3R01AI152078-01S1, U24TR001609-S3, 1K23HL151826NIH); the Mental Wellness Foundation; the Moriah Fund; Octapharma; the Healthnetwork Foundation; the Shear Family Foundation; the NorthShore Research Institute; and the Rice Foundation.


Assuntos
Anticorpos Antivirais , Soroterapia para COVID-19 , COVID-19 , Hospitalização , Imunização Passiva , SARS-CoV-2 , Humanos , COVID-19/imunologia , COVID-19/terapia , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , Imunização Passiva/métodos , Hospitalização/estatística & dados numéricos , SARS-CoV-2/imunologia , Masculino , Feminino , Pessoa de Meia-Idade , Adulto , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Anticorpos Neutralizantes/imunologia , Anticorpos Neutralizantes/sangue , Método Duplo-Cego , Idoso , Doadores de Sangue/estatística & dados numéricos , Pacientes Ambulatoriais
20.
SAGE Open Med ; 11: 20503121231178336, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37324122

RESUMO

Objective: Tube thoracostomy is a life-saving procedure that must be performed competently and expeditiously by emergency care providers. The primary objective of this project was to develop a simple, easily-reproducible, and realistic simulation model for tube thoracostomy placement by learners of emergency medicine. Methods: This chest tube simulator utilizes two slabs of pork ribs with associated intercostal muscle and fascial planes to aid learners in identifying anatomic landmarks, palpating intercostal spaces, and performing blunt dissection in a manner that approximates human anatomy. Holes are cut on both sides of a 1.8-bushel capacity rectangular plastic clothing hamper, and rib slabs are secured to the hamper with zip ties or metal wire. A bed pillow with plastic cover is then placed inside of the plastic hamper to simulate lung tissue. The rib-hamper complex is then wrapped with cellophane or elastic compression bandages to further anchor the rib slabs and simulate skin and subcutaneous tissues. Results: The initial cost of our thoracostomy model is approximately $50, much less than the $1,000-$3,000 cost for a commercial model. Although the hamper and pillow can be reused an indefinite number of times, the other components of our model must be replaced occasionally. Assuming a lifespan of 1,000 uses, our model costs approximately $1.78 per attempt, compared to $4.00 per attempt with the cheapest commercial mannequin system. In fact, assuming a longer useful lifespan for the mannequin does not substantially improve this comparison (e.g. $3.10 versus $1.77 per attempt for a 10,000 attempt lifespan for the commercial mannequin), largely due to the higher cost of commercial replacement skin pads when compared to the components consumed in our model with each attempt. Conclusions: We describe a porcine thoracostomy model that simulates the look and feel of human ribs for purposes of tube thoracostomy training, although it could also be used for thoracentesis and thoracotomy simulation. This model is relatively cheap (costing around $50) and easy to produce within a few minutes utilizing commonly-available materials. Further study is needed to determine whether an inexpensive model like ours provides the same educational value as more expensive commercial mannequin models.

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