Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 99
Filtrar
1.
Redox Biol ; 77: 103348, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-39332053

RESUMO

Fuchs endothelial corneal dystrophy (FECD), the leading indication for corneal transplantation in the U.S., causes loss of corneal endothelial cells (CECs) and corneal edema leading to vision loss. FECD pathogenesis is linked to impaired response to oxidative stress and environmental ultraviolet A (UVA) exposure. Although UVA is known to cause nonapoptotic oxidative cell death resulting from iron-mediated lipid peroxidation, ferroptosis has not been characterized in FECD. We investigated the roles of genetic background and UVA exposure in causing CEC degeneration in FECD. Using ungenotyped FECD patient surgical samples, we found increased levels of cytosolic ferrous iron (Fe2+) and lipid peroxidation in end-stage diseased tissues compared with healthy controls. Using primary and immortalized cell cultures modeling the TCF4 intronic trinucleotide repeat expansion genotype, we found altered gene and protein expression involved in ferroptosis compared to controls including elevated levels of Fe2+, basal lipid peroxidation, and the ferroptosis-specific marker transferrin receptor 1. Increased cytosolic Fe2+ levels were detected after physiologically relevant doses of UVA exposure, indicating a role for ferroptosis in FECD disease progression. Cultured cells were more prone to ferroptosis induced by RSL3 and UVA than controls, indicating ferroptosis susceptibility is increased by both FECD genetic background and UVA. Finally, cell death was preventable after RSL3 induced ferroptosis using solubilized ubiquinol, indicating a role for anti-ferroptosis therapies in FECD. This investigation demonstrates that genetic background and UVA exposure contribute to iron-mediated lipid peroxidation and cell death in FECD, and provides the basis for future investigations of ferroptosis-mediated disease progression in FECD.


Assuntos
Ferroptose , Distrofia Endotelial de Fuchs , Ferro , Peroxidação de Lipídeos , Fator de Transcrição 4 , Expansão das Repetições de Trinucleotídeos , Raios Ultravioleta , Humanos , Distrofia Endotelial de Fuchs/genética , Distrofia Endotelial de Fuchs/metabolismo , Distrofia Endotelial de Fuchs/patologia , Raios Ultravioleta/efeitos adversos , Ferroptose/genética , Ferro/metabolismo , Fator de Transcrição 4/genética , Fator de Transcrição 4/metabolismo , Masculino , Feminino , Idoso , Pessoa de Meia-Idade , Estresse Oxidativo , Endotélio Corneano/metabolismo , Endotélio Corneano/patologia , Endotélio Corneano/efeitos da radiação
2.
Lancet Respir Med ; 12(8): 599-607, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38701817

RESUMO

BACKGROUND: Delirium is common during critical illness and is associated with long-term cognitive impairment and disability. Antipsychotics are frequently used to treat delirium, but their effects on long-term outcomes are unknown. We aimed to investigate the effects of antipsychotic treatment of delirious, critically ill patients on long-term cognitive, functional, psychological, and quality-of-life outcomes. METHODS: This prespecified, long-term follow-up to the randomised, double-blind, placebo-controlled phase 3 MIND-USA Study was conducted in 16 hospitals throughout the USA. Adults (aged ≥18 years) who had been admitted to an intensive care unit with respiratory failure or septic or cardiogenic shock were eligible for inclusion in the study if they had delirium. Participants were randomly assigned-using a computer-generated, permuted-block randomisation scheme with stratification by trial site and age-in a 1:1:1 ratio to receive intravenous placebo, haloperidol, or ziprasidone for up to 14 days. Investigators and participants were masked to treatment group assignment. 3 months and 12 months after randomisation, we assessed survivors' cognitive, functional, psychological, quality-of-life, and employment outcomes using validated telephone-administered tests and questionnaires. This trial was registered with ClinicalTrials.gov, NCT01211522, and is complete. FINDINGS: Between Dec 7, 2011, and Aug 12, 2017, we screened 20 914 individuals, of whom 566 were eligible and consented or had consent provided to participate. Of these 566 patients, 184 were assigned to the placebo group, 192 to the haloperidol group, and 190 to the ziprasidone group. 1-year survival and follow-up rates were similar between groups. Cognitive impairment was common in all three treatment groups, with a third of survivors impaired at both 3-month and 12-month follow-up in all groups. More than half of the surveyed survivors in each group had cognitive or physical limitations (or both) that precluded employment at both 3-month and 12-month follow-up. At both 3 months and 12 months, neither haloperidol (adjusted odds ratio 1·22 [95% CI 0·73-2.04] at 3 months and 1·12 [0·60-2·11] at 12 months) nor ziprasidone (1·07 [0·59-1·96] at 3 months and 0·94 [0·62-1·44] at 12 months) significantly altered cognitive outcomes, as measured by the Telephone Interview for Cognitive Status T score, compared with placebo. We also found no evidence that functional, psychological, quality-of-life, or employment outcomes improved with haloperidol or ziprasidone compared with placebo. INTERPRETATION: In delirious, critically ill patients, neither haloperidol nor ziprasidone had a significant effect on cognitive, functional, psychological, or quality-of-life outcomes among survivors. Our findings, along with insufficient evidence of short-term benefit and frequent inappropriate continuation of antipsychotics at hospital discharge, indicate that antipsychotics should not be used routinely to treat delirium in critically ill adults. FUNDING: National Institutes of Health and the US Department of Veterans Affairs.


Assuntos
Antipsicóticos , Estado Terminal , Delírio , Qualidade de Vida , Humanos , Antipsicóticos/uso terapêutico , Antipsicóticos/efeitos adversos , Delírio/tratamento farmacológico , Masculino , Estado Terminal/psicologia , Estado Terminal/terapia , Feminino , Pessoa de Meia-Idade , Método Duplo-Cego , Idoso , Haloperidol/uso terapêutico , Resultado do Tratamento , Piperazinas/uso terapêutico , Piperazinas/efeitos adversos , Adulto , Tiazóis/uso terapêutico , Tiazóis/efeitos adversos , Tiazóis/administração & dosagem , Seguimentos , Unidades de Terapia Intensiva
3.
J Anesth ; 38(3): 354-363, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38507058

RESUMO

PURPOSE: Prolonged mechanical ventilation (MV) subjects multiple trauma patients to ventilator-induced diaphragmatic dysfunction. There is limited evidence on the predictive role of diaphragm ultrasound (DUS) for weaning success in multiple trauma patients. Therefore, we evaluated Ultrasound of the diaphragm as a valuable indicator of weaning outcomes, in trauma patients. MATERIAL AND METHODS: This prospective cohort study included 50 trauma patients from September 2018 to February 2019. DUS was performed twice: upon ICU admission and the first weaning attempt. The diagnostic accuracy of indexes was evaluated by ROC curves. RESULTS: The study included patients with a mean age of 35.4 ± 17.37, and 78% being male. The median injury severity score was 75 (42-75). The failure group exhibited significantly lower right diaphragmatic excursion (DE) compared to the success group (P = 0.006). In addition, the failure group experienced a significant decrease in both right and left DE from admission to the first attempt of weaning from MV (P < 0.001). Both groups showed a significant decrease in inspiratory and expiratory thickness on both sides during weaning from MV compared to the admission time (P < 0.001). The findings from the ROC analysis indicated that the Rapid shallow breathing index (RSBI) (Sensitivity = 91.67, Specificity = 100), respiratory rate (RR)/DE (Right: Sensitivity = 87.5, Specificity = 92.31), and RR/TF (Thickening Fraction) (Right: Sensitivity = 83.33, Specificity = 80.77) demonstrated high sensitivity and specificity in predicting weaning outcome. CONCLUSION: In the context of patients with multiple trauma, employing DUC and assessing diaphragmatic excursion, thickness, RR/DE index, RR/TF index, and RSBI can aid in determining successful ventilator weaning.


Assuntos
Diafragma , Ultrassonografia , Desmame do Respirador , Humanos , Desmame do Respirador/métodos , Diafragma/diagnóstico por imagem , Diafragma/fisiopatologia , Masculino , Feminino , Estudos Prospectivos , Ultrassonografia/métodos , Adulto , Pessoa de Meia-Idade , Respiração Artificial/métodos , Traumatismo Múltiplo/diagnóstico por imagem , Traumatismo Múltiplo/fisiopatologia , Estudos de Coortes , Adulto Jovem
4.
Am J Pathol ; 194(6): 1090-1105, 2024 06.
Artigo em Inglês | MEDLINE | ID: mdl-38403162

RESUMO

Changes in the anterior segment of the eye due to type 2 diabetes mellitus (T2DM) are not well-characterized, in part due to the lack of a reliable animal model. This study evaluated changes in the anterior segment, including crystalline lens health, corneal endothelial cell density, aqueous humor metabolites, and ciliary body vasculature, in a rat model of T2DM compared with human eyes. Male Sprague-Dawley rats were fed a high-fat diet (45% fat) or normal diet, and rats fed the high-fat diet were injected with streptozotocin intraperitoneally to generate a model of T2DM. Cataract formation and corneal endothelial cell density were assessed using microscopic analysis. Diabetes-related rat aqueous humor alterations were assessed using metabolomics screening. Transmission electron microscopy was used to assess qualitative ultrastructural changes ciliary process microvessels at the site of aqueous formation in the eyes of diabetic rats and humans. Eyes from the diabetic rats demonstrated cataracts, lower corneal endothelial cell densities, altered aqueous metabolites, and ciliary body ultrastructural changes, including vascular endothelial cell activation, pericyte degeneration, perivascular edema, and basement membrane reduplication. These findings recapitulated diabetic changes in human eyes. These results support the use of this model for studying ocular manifestations of T2DM and support a hypothesis postulating blood-aqueous barrier breakdown and vascular leakage at the ciliary body as a mechanism for diabetic anterior segment pathology.


Assuntos
Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 2 , Ratos Sprague-Dawley , Animais , Diabetes Mellitus Tipo 2/patologia , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/complicações , Masculino , Ratos , Humanos , Diabetes Mellitus Experimental/patologia , Diabetes Mellitus Experimental/complicações , Modelos Animais de Doenças , Segmento Anterior do Olho/patologia , Humor Aquoso/metabolismo , Catarata/patologia , Catarata/metabolismo , Cristalino/patologia , Cristalino/metabolismo , Cristalino/ultraestrutura , Corpo Ciliar/patologia , Corpo Ciliar/metabolismo , Dieta Hiperlipídica/efeitos adversos
5.
Invest Ophthalmol Vis Sci ; 64(7): 26, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37326594

RESUMO

Purpose: There is a pressing need to investigate the impact of type II diabetes mellitus on the posterior cornea in donor tissues given its increasing prevalence and potential impact on endothelial keratoplasty surgical outcomes. Methods: Immortalized human cultured corneal endothelial cells (CECs; HCEC-B4G12) were grown in hyperglycemic media for 2 weeks. Extracellular matrix (ECM) adhesive glycoprotein expression and advanced glycation end products (AGEs) in cultured cells and corneoscleral donor tissues, as well as the elastic modulus for the Descemet membrane (DMs) and CECs of diabetic and nondiabetic donor corneas, were measured. Results: In CEC cultures, increasing hyperglycemia resulted in increased transforming growth factor beta-induced (TGFBI) protein expression and colocalization with AGEs in the ECM. In donor corneas, the thicknesses of the DM and the interfacial matrix (IFM) between the DM and stroma both increased from 8.42 ± 1.35 µm and 0.504 ± 0.13 µm in normal corneas, respectively, to 11.13 ± 2.91 µm (DM) and 0.681 ± 0.24 µm (IFM) in non-advanced diabetes (P = 0.013 and P = 0.075, respectively) and 11.31 ± 1.76 µm (DM) and 0.744 ± 0.18 µm (IFM) in advanced diabetes (AD; P = 0.0002 and P = 0.003, respectively). Immunofluorescence in AD tissues versus controls showed increased AGEs (P < 0.001) and markedly increased labeling intensity for adhesive glycoproteins, including TGFBI, that colocalized with AGEs. The elastic modulus significantly increased between AD and control tissues for the DMs (P < 0.0001) and CECs (P < 0.0001). Conclusions: Diabetes and hyperglycemia alter human CEC ECM structure and composition, likely contributing to previously documented complications of endothelial keratoplasty using diabetic donor tissue, including tearing during graft preparation and reduced graft survival. AGE accumulation in the DM and IFM may be a useful biomarker for determining diabetic impact on posterior corneal tissue.


Assuntos
Ceratoplastia Endotelial com Remoção da Lâmina Limitante Posterior , Diabetes Mellitus Tipo 2 , Hiperglicemia , Humanos , Lâmina Limitante Posterior/metabolismo , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/metabolismo , Células Endoteliais , Ceratoplastia Endotelial com Remoção da Lâmina Limitante Posterior/métodos , Córnea , Matriz Extracelular , Hiperglicemia/metabolismo , Produtos Finais de Glicação Avançada/metabolismo , Doadores de Tecidos , Endotélio Corneano/metabolismo
6.
Physiol Rep ; 11(4): e15602, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36802120

RESUMO

Optimal oxygenation in the intensive care unit requires adequate pulmonary gas exchange, oxygen-carrying capacity in the form of hemoglobin, sufficient delivery of oxygenated hemoglobin to the tissue, and an appropriate tissue oxygen demand. In this Case Study in Physiology, we describe a patient with COVID-19 whose pulmonary gas exchange and oxygen delivery were severely compromised by COVID-19 pneumonia requiring extracorporeal membrane oxygenation (ECMO) support. His clinical course was complicated by a secondary superinfection with staphylococcus aureus and sepsis. This case study is provided with two goals in mind (1) We outline how basic physiology was used to address life-threatening consequences of a novel infection-COVID-19. (2) We describe a strategy of whole-body cooling to lower the cardiac output and oxygen consumption, use of the shunt equation to optimize flow to the ECMO circuit, and transfusion to improve oxygen-carrying capacity when ECMO alone failed to provide sufficient oxygenation.


Assuntos
COVID-19 , Superinfecção , Humanos , Superinfecção/terapia , Débito Cardíaco , Oxigênio , Hemoglobinas
7.
PLoS One ; 18(1): e0280491, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36652491

RESUMO

Diabetes mellitus is a multiorgan systemic disease impacting numerous ocular structures that results in significant ocular morbidity and often results in more frequent corneal and glaucoma surgeries for affected individuals. We hypothesize that the systemic metabolic and proteomic derangement observed in the progression of diabetes influences the composition of the aqueous humor (AH), which ultimately impacts the anterior segment health of the eye. To identify changes associated with diabetes progression, we mapped the metabolite profile and proteome of AH samples from patients with varying severities of type II diabetes (T2DM). Patients were classified as nondiabetic (ND or control), non-insulin-dependent diabetic without advanced features of disease (NAD-ni), insulin-dependent diabetic without advanced features (NAD-i), or diabetic with advanced features (AD). AH samples collected from the anterior chamber during elective ophthalmic surgery were evaluated for metabolite and protein expression changes associated with diabetic severity via gas chromatography/mass spectrometry and ultra-high performance liquid chromatography tandem mass spectrometry, respectively. Metabolic and proteomic pathway analyses were conducted utilizing MetaboAnalyst 4.0 and Ingenuity Pathway Analysis. A total of 14 control, 12 NAD-ni, 4 NAD-I, and 14 AD samples were included for analysis. Elevated levels of several branched amino acids (e.g., valine, leucine, isoleucine), and lipid metabolites (e.g., palmitate) were found only with increasing diabetic severity (i.e., the AD group). Similar proteomic trends were noted in amino acid and fatty acid metabolism and the unfolded protein/stress response. These results represent the first report of both metabolomic and proteomic evaluation of aqueous humor. Diabetes results in metabolic and proteomic perturbations detectable in the AH, and unique changes become manifest as T2DM severity worsens. Changes in AH composition may serve as an indicator of disease severity, risk assessment of anterior segment cells and structures, and potential future therapies.


Assuntos
Humor Aquoso , Diabetes Mellitus Tipo 2 , Humanos , Humor Aquoso/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Proteômica , NAD/metabolismo , Cromatografia Líquida
8.
Clin Chest Med ; 43(3): 393-400, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36116809

RESUMO

Capnography has been widely adopted in multiple clinical areas. The capnogram and end-tidal carbon dioxide offer a wealth of information, in the right clinical setting, and when properly interpreted. In this article, the authors aim to review the most common clinical scenarios during which capnography has been shown to be of benefit. This includes the areas of fluid responsiveness, cardiopulmonary resuscitation, and conscious sedation. They review the published literature, highlighting its pitfalls and identifying its limitations.


Assuntos
Capnografia , Estado Terminal , Dióxido de Carbono , Estado Terminal/terapia , Humanos
10.
Annu Rev Med ; 73: 81-93, 2022 01 27.
Artigo em Inglês | MEDLINE | ID: mdl-35084996

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a respiratory virus that gains entry via angiotensin-converting enzyme 2 (ACE2) within airway epithelium. Patients exhibit a spectrum of respiratory symptoms from asymptomatic to respiratory failure. Patient factors including obesity, tobacco use, and black race are all associated with increased ACE2 expression and may contribute to increased complications. Consolidation and ground-glass opacities on chest imaging are typical but not specific for coronavirus disease 2019 (COVID-19). Venous thromboembolism occurs infrequently when prophylactic anticoagulation is provided. However, capillary microthrombosis is nearly ubiquitous, suggesting that it contributes to hypoxemia. Remdesivir and glucocorticoids may benefit some hospitalized patients. Many of those afflicted remain symptomatic two weeks following diagnosis and continue to require health care. Total lung capacity, diffusion capacity, and maximal oxygen consumption may be reduced for months in some survivors. Lung transplant offers chronically critically ill patients new hope, and this option may have increasing potential for outpatients with COVID-19-associated fibrosis.


Assuntos
COVID-19 , Fibrose , Humanos , Pulmão/patologia , SARS-CoV-2
11.
Biomaterials ; 275: 120842, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34087583

RESUMO

Defective cellular metabolism, impaired mitochondrial function, and increased cell death are major problems that adversely affect donor tissues during hypothermic preservation prior to transplantation. These problems are thought to arise from accumulated reactive oxygen species (ROS) inside cells. Oxidative stress acting on the cells of organs and tissues preserved in hypothermic conditions before surgery, as is the case for cornea transplantation, is thought to be a major reason behind cell death prior to surgery and decreased graft survival after transplantation. We have recently discovered that ubiquinol - the reduced and active form of coenzyme Q10 and a powerful antioxidant - significantly enhances mitochondrial function and reduces apoptosis in human donor corneal endothelial cells. However, ubiquinol is highly lipophilic, underscoring the need for an aqueous-based formulation of this molecule. Herein, we report a highly dispersible and stable formulation comprising a complex of ubiquinol and gamma cyclodextrin (γ-CD) for use in aqueous-phase ophthalmic products. Docking studies showed that γ-CD has the strongest binding affinity with ubiquinol compared to α- or ß-CD. Complexed ubiquinol showed significantly higher stability compared to free ubiquinol in different aqueous ophthalmic products including Optisol-GS® corneal storage medium, balanced salt solution for intraocular irrigation, and topical Refresh® artificial tear eye drops. Greater ROS scavenging activity was noted in a cell model with high basal metabolism and ROS generation (A549) and in HCEC-B4G12 human corneal endothelial cells after treatment with ubiquinol/γ-CD compared to free ubiquinol. Furthermore, complexed ubiquinol was more effective at lowering ROS, and at far lower concentrations, compared to free ubiquinol. Complexed ubiquinol inhibited lipid peroxidation and protected HCEC-B4G12 cells against erastin-induced ferroptosis. No evidence of cellular toxicity was detected in HCEC-B4G12 cells after treatment with complexed ubiquinol. Using a vertical diffusion system, a topically applied inclusion complex of γ-CD and a lipophilic dye (coumarin-6) demonstrated transcorneal penetrance in porcine corneas and the capacity for the γ-CD vehicle to deliver drug to the corneal endothelium. Using the same model, topically applied ubiquinol/γ-CD complex penetrated the entire thickness of human donor corneas with markedly greater ubiquinol retention in the endothelium compared to free ubiquinol. Lastly, the penetrance of ubiquinol/γ-CD complex was assayed using human donor corneas preserved for 7 days in Optisol-GS® per standard industry practices, and demonstrated higher amounts of ubiquinol retained in the corneal endothelium compared to free ubiquinol. In summary, ubiquinol complexed with γ-CD is a highly stable composition that can be incorporated into a variety of aqueous-phase products for ophthalmic use including donor corneal storage media and topical eye drops to scavenge ROS and protect corneal endothelial cells against oxidative damage.


Assuntos
Transplante de Córnea , Células Endoteliais , Animais , Córnea , Meios de Cultura Livres de Soro , Dextranos , Endotélio Corneano , Gentamicinas , Humanos , Preservação de Órgãos , Suínos , Ubiquinona/análogos & derivados
12.
Invest Ophthalmol Vis Sci ; 62(3): 22, 2021 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-33724294

RESUMO

Mitochondrial function is essential for the viability of aerobic eukaryotic cells, as mitochondria provide energy through the generation of adenosine triphosphate (ATP), regulate cellular metabolism, provide redox balancing, participate in immune signaling, and can initiate apoptosis. Mitochondria are dynamic organelles that participate in a cyclical and ongoing process of regeneration and autophagy (clearance), termed mitophagy specifically for mitochondrial (macro)autophagy. An imbalance in mitochondrial function toward mitochondrial dysfunction can be catastrophic for cells and has been characterized in several common ophthalmic diseases. In this article, we review mitochondrial homeostasis in detail, focusing on the balance of mitochondrial dynamics including the processes of fission and fusion, and provide a description of the mechanisms involved in mitophagy. Furthermore, this article reviews investigations of ocular diseases with impaired mitophagy, including Fuchs endothelial corneal dystrophy, primary open-angle glaucoma, diabetic retinopathy, and age-related macular degeneration, as well as several primary mitochondrial diseases with ocular phenotypes that display impaired mitophagy, including mitochondrial encephalopathy lactic acidosis stroke, Leber hereditary optic neuropathy, and chronic progressive external ophthalmoplegia. The results of various studies using cell culture, animal, and human tissue models are presented and reflect a growing awareness of mitophagy impairment as an important feature of ophthalmic disease pathology. As this review indicates, it is imperative that mitophagy be investigated as a targetable mechanism in developing therapies for ocular diseases characterized by oxidative stress and mitochondrial dysfunction.


Assuntos
Retinopatia Diabética/fisiopatologia , Distrofia Endotelial de Fuchs/fisiopatologia , Glaucoma de Ângulo Aberto/fisiopatologia , Degeneração Macular/fisiopatologia , Mitocôndrias/fisiologia , Doenças Mitocondriais/fisiopatologia , Mitofagia/fisiologia , Animais , Humanos , Terapia de Alvo Molecular
13.
J Intensive Care Med ; 36(6): 696-703, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33706592

RESUMO

OBJECTIVE: Many patients with coronavirus disease 2019 (COVID-19) need mechanical ventilation secondary to acute respiratory distress syndrome. Information on the respiratory system mechanical characteristics of this disease is limited. The aim of this study is to describe the respiratory system mechanical properties of ventilated COVID-19 patients. DESIGN, SETTING, AND PATIENTS: Patients consecutively admitted to the medical intensive care unit at the University of Iowa Hospitals and Clinics in Iowa City, USA, from April 19 to May 1, 2020, were prospectively studied; final date of follow-up was May 1, 2020. MEASUREMENTS: At the time of first patient contact, ventilator information was collected including mode, settings, peak airway pressure, plateau pressure, and total positive end expiratory pressure. Indices of airflow resistance and respiratory system compliance were calculated and analyzed. MAIN RESULTS: The mean age of the patients was 58 years. 6 out of 12 (50%) patients were female. Of the 21 laboratory-confirmed COVID-19 patients on invasive mechanical ventilation, 9 patients who were actively breathing on the ventilator were excluded. All the patients included were on volume-control mode. Mean [±standard deviation] ventilator indices were: resistive pressure 19 [±4] cmH2O, airway resistance 20 [±4] cmH2O/L/s, and respiratory system static compliance 39 [±16] ml/cmH2O. These values are consistent with abnormally elevated resistance to airflow and reduced respiratory system compliance. Analysis of flow waveform graphics revealed a pattern consistent with airflow obstruction in all patients. CONCLUSIONS: Severe respiratory failure due to COVID-19 is regularly associated with airflow obstruction.


Assuntos
Obstrução das Vias Respiratórias/virologia , COVID-19/complicações , COVID-19/terapia , Respiração Artificial , Síndrome do Desconforto Respiratório/virologia , Adulto , Idoso , Obstrução das Vias Respiratórias/fisiopatologia , Resistência das Vias Respiratórias/fisiologia , Estudos de Coortes , Cuidados Críticos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Ventilação Pulmonar/fisiologia , Síndrome do Desconforto Respiratório/fisiopatologia
14.
J Crit Care ; 61: 21-28, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33049489

RESUMO

PURPOSE: To create a simplified critical illness severity scoring system with high prediction accuracy for 30-day mortality using only commonly available variables. MATERIALS AND METHODS: This is a retrospective cohort study of ICU admissions 2010-2015 in 306 ICUs in 117 Veterans Affairs (VA) hospitals. We randomly divided our cohort into a training dataset (75%) and a validation dataset (25%). We created a critical illness severity scoring system (CISSS) using age, comorbidities, heart rate, mean arterial blood pressure, temperature, respiratory rate, hematocrit, white blood cell count, creatinine, sodium, glucose, albumin, bilirubin, bicarbonate, use of invasive mechanical ventilation, and whether the admission was surgical or not. We validated the performance of CISSS to predict 30-day mortality internally. RESULTS: After excluding 31,743 re-admissions, we divided our sample (n = 534,001) into a training (n = 400,613) and a validation dataset (n = 133,388). In the training dataset, the area under the curve (AUC) of CISSS was 0.847(95%CI = 0.845-0.850). In the validation dataset, the AUC was 0.848 (95%CI = 0.844-0.852), the standardized mortality ratio (SMR) was 1.00 (95%CI = 0.98-1.02), and Brier's score for 30-day mortality was 0.058 (95%CI = 0.057-0.059). CISSS calibration was acceptable. CONCLUSIONS: CISSS has very good performance and requires only commonly used variables that can be easily extracted by electronic health records.


Assuntos
Estado Terminal , Unidades de Terapia Intensiva , APACHE , Mortalidade Hospitalar , Humanos , Estudos Retrospectivos , Índice de Gravidade de Doença
15.
Cornea ; 40(3): 292-298, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-32732698

RESUMO

PURPOSE: To assess how trypan blue staining affects Descemet membrane endothelial keratoplasty (DMEK) graft visibility and corneal endothelial cell (CEC) mitochondrial respiration. METHODS: DMEK grafts (n = 20) were stained with trypan blue 0.06% for 1, 3, 5, or 10 minutes. Each graft was injected into an artificial anterior chamber. Surgery was simulated with tapping and sweeping motions on the corneal surface and injections of balanced salt solution (BSS). Graft visibility was assessed at 5, 10, 20, and 30 minutes. Effects of trypan blue on mitochondrial respiration were assessed using primary CECs cultured from donor corneas (n = 43). Treatment wells exposed to trypan blue 0.06% (1, 5, or 30 minutes) and donor-matched control wells to methylene blue 1% (1 minute) or BSS (1, 5, or 30 minutes) were assayed for key respiration parameters. RESULTS: After 5 minutes of surgical manipulation, grafts stained for 5 minutes were significantly more visible than grafts stained for 1 or 3 minutes; there was no added benefit of staining for 10 minutes. After 10 minutes of surgical manipulation, grafts stained for 3 minutes were more visible than grafts stained for 1 minute, without additional benefits of staining ≥5 minutes. No visibility differences were observed after ≥20 minutes of surgical manipulation. CEC mitochondrial respiration did not change significantly following trypan blue exposure for all intervals tested compared to BSS. CONCLUSIONS: Staining DMEK grafts with trypan blue for 3 to 5 minutes optimizes visibility during surgical manipulation without mitochondrial impairment. Corneal surgeons learning DMEK will benefit from optimizing this critical step.


Assuntos
Corantes/farmacologia , Ceratoplastia Endotelial com Remoção da Lâmina Limitante Posterior , Endotélio Corneano/anatomia & histologia , Endotélio Corneano/efeitos dos fármacos , Mitocôndrias/fisiologia , Azul Tripano/farmacologia , Perda de Células Endoteliais da Córnea/cirurgia , Endotélio Corneano/metabolismo , Humanos , Pessoa de Meia-Idade , Coloração e Rotulagem/métodos , Fatores de Tempo , Doadores de Tecidos , Coleta de Tecidos e Órgãos
17.
Am J Ophthalmol ; 224: 185-199, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33316261

RESUMO

PURPOSE: Rho-associated kinase (ROCK) inhibitors have been successfully used as a rescue strategy in eyes that failed to clear after descemetorhexis without endothelial graft for treatment of Fuchs endothelial corneal dystrophy (FECD). The functional mechanisms by which ROCK inhibitors modulate corneal endothelial cell regeneration in FECD patients have, however, not been clarified. Here, we analyzed the effect of the ROCK inhibitor ripasudil on corneal endothelial cells of FECD patients and normal donors using ex vivo tissue and in vitro cellular models. DESIGN: Experimental study: laboratory investigation. METHODS: This institutional study used endothelial cell-Descemet membrane lamellae from FECD patients (n = 450) undergoing Descemet membrane endothelial keratoplasty (FECD ex vivo model), normal research-grade donor corneas (n = 30) after scraping off central endothelial cells (ex vivo wound healing model), normal donor corneas (n = 20) without endothelial injury, and immortalized cell lines (n = 3) generated from FECD patients (FECD in vitro model). Descemet membrane lamellae were dissected into halves and incubated for 24-72 hours in storage medium with or without a single dose of 30 µM ripasudil. The effects of ripasudil on expression of genes and proteins related to endothelial cell proliferation, migration, functionality, and endothelial-to-mesenchymal transition were analyzed and complemented by functional assays on FECD cell lines. RESULTS: A single dose of ripasudil induced significant upregulation of genes and proteins related to cell cycle progression, cell-matrix adhesion and migration, as well as endothelial barrier and pump function up to 72 hours, whereas classical markers of endothelial-to-mesenchymal transition were downregulated in both FECD and normal specimens compared to unstimulated controls ex vivo. In addition to stimulation of proliferation and migration, ripasudil-induced changes in expression of functional signature genes could be also verified in FECD cell lines in vitro. CONCLUSIONS: These data support the concept that inhibition of ROCK signaling represents a potent tool in regenerative therapies in FECD patients through reactivation of cell proliferation and migration as well as restoration of endothelial pump and barrier function without inducing adverse phenotypic changes.


Assuntos
Endotélio Corneano/efeitos dos fármacos , Distrofia Endotelial de Fuchs/tratamento farmacológico , Quinases Associadas a rho/antagonistas & inibidores , Idoso , Ciclo Celular/fisiologia , Proteínas de Ciclo Celular/metabolismo , Movimento Celular/fisiologia , Proliferação de Células/fisiologia , Junções Célula-Matriz/metabolismo , Células Cultivadas , Ceratoplastia Endotelial com Remoção da Lâmina Limitante Posterior , Relação Dose-Resposta a Droga , Endotélio Corneano/fisiologia , Feminino , Distrofia Endotelial de Fuchs/metabolismo , Humanos , Isoquinolinas , Masculino , Pessoa de Meia-Idade , Sulfonamidas
18.
Cornea ; 39(10): 1285-1290, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32558735

RESUMO

PURPOSE: To determine whether ubiquinol improves mitochondrial function and cell viability in human donor corneal endothelial cells during hypothermic corneal tissue storage. METHODS: Endothelial cell Descemet membrane tissues were treated with 10 µM ubiquinol, the reduced form of the antioxidant coenzyme Q10, for 5 days in Optisol-GS storage media before assaying for mitochondrial activity using extracellular flux analysis of oxygen consumption. In addition, endothelial cell Descemet membrane tissues were analyzed for cell viability using apoptosis and necrosis assays. Control tissues from mate corneas were treated with diluent only, and comparisons were analyzed for differences. RESULTS: A total of 13 donor corneal tissues with a mean (SEM) preservation time of 11.8 days (0.4) were included for the analysis. Treatment with 10 µM ubiquinol increased spare respiratory capacity by 174% (P = 0.001), maximal respiration by 93% (P = 0.003), and proton leak by 80% (P = 0.047) compared with controls. Cells treated with ubiquinol had no significant change in cell necrosis or apoptosis. CONCLUSIONS: Preliminary testing in donor corneal tissue at specified doses indicates that ubiquinol may be a useful biocompatible additive to hypothermic corneal storage media that increases corneal endothelial cell mitochondrial function. Additional investigations are indicated to further study and optimize the dose and formulation of ubiquinol for use in preserving donor corneal tissue function during hypothermic storage.


Assuntos
Respiração Celular/fisiologia , Endotélio Corneano/efeitos dos fármacos , Micronutrientes/farmacologia , Mitocôndrias/metabolismo , Ubiquinona/análogos & derivados , Idoso , Contagem de Células , Sobrevivência Celular/efeitos dos fármacos , Sulfatos de Condroitina , Misturas Complexas , Criopreservação , Lâmina Limitante Posterior/efeitos dos fármacos , Dextranos , Feminino , Gentamicinas , Humanos , Masculino , Pessoa de Meia-Idade , Preservação de Órgãos , Soluções para Preservação de Órgãos , Doadores de Tecidos , Ubiquinona/farmacologia
19.
Intensive Crit Care Nurs ; 60: 102872, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32389395

RESUMO

OBJECTIVES: ABCDEF bundle implementation in the Intensive Care Unit (ICU) is associated with dose dependent improvements in patient outcomes. The objective was to compare nurse attitudes about the ABCDEF bundle to self-reported adherence to bundle components. RESEARCH METHODOLOGY/DESIGN: Cross-sectional study. SETTING: Nurses providing direct patient care in 28 ICUs within 18 hospitals across the United States. MAIN OUTCOME MEASURES: 53-item survey of attitudes and practice of the ABCDEF bundle components was administered between November 2011 and August 2015 (n = 1661). RESULTS: We did not find clinically significant correlations between nurse attitudes and adherence to Awakening trials, Breathing trials, and sedation protocol adherence (rs = 0.05-0.28) or sedation plan discussion during rounds and Awakening and Breathing trial Coordination (rs = 0.19). Delirium is more likely to be discussed during rounds when ICU physicians and nurse managers facilitate delirium reduction (rs = 0.27-0.36). Early mobilization is more likely to occur when ICU physicians, nurse managers, staffing, equipment, and the ICU environment facilitate early mobility (rs = 0.36-0.47). Physician leadership had the strongest correlation with reporting an ICU environment that facilitates ABCDEF bundle implementation (rs = 0.63-0.74). CONCLUSIONS: Nurse attitudes about bundle implementation did not predict bundle adherence. Nurse manager and physician leadership played a large role in creating a supportive ICU environment.


Assuntos
Enfermeiras e Enfermeiros/psicologia , Pacotes de Assistência ao Paciente/normas , Percepção , Adulto , Atitude do Pessoal de Saúde , Cuidados Críticos/métodos , Estudos Transversais , Delírio/enfermagem , Delírio/psicologia , Deambulação Precoce/enfermagem , Deambulação Precoce/psicologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Enfermeiras e Enfermeiros/estatística & dados numéricos , Pacotes de Assistência ao Paciente/métodos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...