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1.
JIMD Rep ; 65(3): 144-155, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38736638

RESUMO

Maple syrup urine disease (MSUD) is a disorder of branched-chain amino acid metabolism caused by a defect in the branched-chain α-ketoacid dehydrogenase (BCKD) complex (OMIM #248600). The hallmark presentation is encephalopathic crisis in neonates, but can also present with metabolic decompensation, developmental delays, and feeding difficulties. Biochemical evidence for MSUD includes elevated branched-chain amino acids (BCAA) and the pathognomonic presence of alloisoleucine. The BCKD complex contains several subunits associated with autosomal recessive MSUD, while its regulatory proteins have less well-defined disease associations. We report on two families with the same BCKDK variant (c.1115C>G (p.Thr372Arg)). Probands were detected on newborn screening and demonstrated biochemical evidence of MSUD. The variant was identified in reportedly asymptomatic parents and additional family members who had elevated BCAA and alloisoleucine, following an autosomal dominant pattern of inheritance. To better define the functional effect of the variant on the kinase, we completed molecular modeling using sequence-based (2D), structural-based (3D), and dynamic-based (4D) analyses. The BCKDK variant modeling indicated a gain-of-function which leads to impaired BCAA catabolism consistent with the biochemical evidence in this cohort. Combining the evidence gained from molecular modeling with the absence of metabolic decompensation in our patients and several adult family members, despite encountering stressors typically problematic in classic MSUD, we suggest that heterozygous gain-of-function variants in BCKDK may represent a novel biochemical phenotype of MSUD with a benign clinical course.

2.
Transplant Proc ; 56(1): 228-235, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38171992

RESUMO

Orthotopic liver transplantation remains the definitive treatment for patients with end-stage liver disease. Unfortunately, the increasing demand for donor livers and the limited supply of viable organs have both led to a critical need for innovative strategies to expand the pool of transplantable organs. The mitochondrion, central to hepatic cellular function, plays a pivotal role in hepatic ischemic injury, with impaired mitochondrial function and oxidative stress leading to cell death. Mitochondrial protection strategies have shown promise in mitigating IRI and resuscitating marginal organs for transplant. Machine perfusion (MP) has been proven a valuable tool for reviving marginal organs with very promising results. Evaluation of liver viability during perfusion traditionally relies on parameters including lactate clearance, bile production, and transaminase levels. Nevertheless, the quest for more comprehensive and universally applicable viability markers persists. Normothermic regional perfusion has gained robust attention, offering extended recovery time for organs from donation after cardiac death donors. This approach has shown remarkable success in improving organ quality and reducing ischemic injury using the body's physiological conditions. The current challenge lies in the absence of a reliable assessment tool for predicting graft viability and post-transplant outcomes. To address this, exploring insights from mitochondrial function in the context of ischemia-reperfusion injury could offer a promising path toward better patient outcomes and graft longevity. Indeed, hypoxia-induced mitochondrial injury may serve as a surrogate marker of organ viability following oxygenated resuscitation techniques in the future.


Assuntos
Preservação de Órgãos , Traumatismo por Reperfusão , Humanos , Preservação de Órgãos/métodos , Fígado , Traumatismo por Reperfusão/prevenção & controle , Isquemia , Metabolismo Energético , Mitocôndrias , Perfusão/métodos
3.
Cell Rep ; 43(1): 113517, 2024 01 23.
Artigo em Inglês | MEDLINE | ID: mdl-38142397

RESUMO

Randomly barcoded transposon mutant libraries are powerful tools for studying gene function and organization, assessing gene essentiality and pathways, discovering potential therapeutic targets, and understanding the physiology of gut bacteria and their interactions with the host. However, construction of high-quality libraries with uniform representation can be challenging. In this review, we survey various strategies for barcoded library construction, including transposition systems, methods of transposon delivery, optimal library size, and transconjugant selection schemes. We discuss the advantages and limitations of each approach, as well as factors to consider when selecting a strategy. In addition, we highlight experimental and computational advances in arraying condensed libraries from mutant pools. We focus on examples of successful library construction in gut bacteria and their application to gene function studies and drug discovery. Given the need for understanding gene function and organization in gut bacteria, we provide a comprehensive guide for researchers to construct randomly barcoded transposon mutant libraries.


Assuntos
Elementos de DNA Transponíveis , Sequenciamento de Nucleotídeos em Larga Escala , Elementos de DNA Transponíveis/genética , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Clonagem Molecular , Biblioteca Gênica , Bactérias/genética , Mutagênese Insercional/genética
4.
Transplant Direct ; 9(12): e1554, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37928484

RESUMO

Background: Therapeutic donors (TDs) are individuals who undergo organ removal for medical treatment with no replacement organ, and the organ is then transplanted into another person. Transplant centers in the United States have started using TDs for kidney transplantation (KT). TD-KT recipient outcomes may be inferior to those of non-TD-living-donor (non-TD-LD)-KT or deceased-donor (DD)-KT because of the conditions that led to nephrectomy; however, these outcomes have not been sufficiently evaluated. Methods: This was a retrospective cohort study using Organ Procurement and Transplantation Network data. Via optimal matching methods, we created 1:4 fivesomes with highly similar characteristics for TD-KT and non-TD-LD-KT recipients and then separately for TD-KT and DD-KT recipients. We compared a 6-mo estimated glomerular filtration rate (eGFR) between groups (primary endpoint) and a composite of death, graft loss, or eGFR <30 mL/min/1.73 m2 at 6 mo (secondary). Results: We identified 36 TD-KT recipients with 6-mo eGFR. There was also 1 death and 2 graft losses within 6 mo. Mean ± SD 6-mo eGFR was not significantly different between TD-KT, non-TD-LD-KT, and DD-KT recipients (59.9 ± 20.7, 63.3 ± 17.9, and 59.9 ± 23.0 mL/min/1.73 m2, respectively; P > 0.05). However, the 6-mo composite outcome occurred more frequently with TD-KT than with non-TD-LD-KT and DD-KT (18%, 2% [P < 0.001], and 8% [P = 0.053], respectively). Conclusions: Early graft function was no different between well-matched groups, but TD-KT demonstrated a higher risk of otherwise poor 6-mo outcomes compared with non-TD-LD-KT and DD-KT. Our results support selective utilization of TD kidneys; however, additional studies are needed with more detailed TD kidney information to understand how to best utilize these kidneys.

5.
iScience ; 26(10): 107842, 2023 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-37766983

RESUMO

Auxilin (DNAJC6/PARK19), an endocytic co-chaperone, is essential for maintaining homeostasis in the readily releasable pool (RRP) by aiding clathrin-mediated uncoating of synaptic vesicles. Its loss-of-function mutations, observed in familial Parkinson's disease (PD), lead to basal ganglia motor deficits and cortical dysfunction. We discovered that auxilin-knockout (Aux-KO) mice exhibited impaired pre-synaptic plasticity in layer 4 to layer 2/3 pyramidal cell synapses in the primary visual cortex (V1), including reduced short-term facilitation and depression. Computational modeling revealed increased RRP refilling during short repetitive stimulation, which diminished during prolonged stimulation. Silicon probe recordings in V1 of Aux-KO mice demonstrated disrupted visual cortical circuit responses, including reduced orientation selectivity, compromised visual mismatch negativity, and shorter visual familiarity-evoked theta oscillations. Pupillometry analysis revealed an impaired optokinetic response. Auxilin-dependent pre-synaptic endocytosis dysfunction was associated with deficits in pre-synaptic plasticity, visual cortical functions, and eye movement prodromally or at the early stage of motor symptoms.

6.
J Nutr ; 153 Suppl 1: S42-S59, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37714779

RESUMO

Anemia is a multifactorial condition; approaches to address it must recognize that the causal factors represent an ecology consisting of internal (biology, genetics, and health) and external (social/behavioral/demographic and physical) environments. In this paper, we present an approach for selecting interventions, followed by a description of key issues related to the multiple available interventions for prevention and reduction of anemia. We address interventions for anemia using the following 2 main categories: 1) those that address nutrients alone, and, 2) those that address nonnutritional causes of anemia. The emphasis will be on interventions of public health relevance, but we also consider the clinical context. We also focus on interventions at different stages of the life course, with a particular focus on women of reproductive age and preschool-age children, and present evidence on various factors to consider when selecting an intervention-inflammation, genetic mutations, nutrient delivery, bioavailability, and safety. Each section on an intervention domain concludes with a brief discussion of key research areas.


Assuntos
Anemia , Criança , Pré-Escolar , Humanos , Feminino , Anemia/prevenção & controle , Nutrientes , Inflamação
7.
Clin J Am Soc Nephrol ; 18(11): 1466-1475, 2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-37574663

RESUMO

BACKGROUND: Acceptable post-transplant outcomes were reported in kidney transplant recipients from donors with coronavirus disease 2019 (COVID-19); however, there are no comparative studies with well-matched controls. METHODS: This multicenter, prospective observational study, which included three transplant centers in the United States, enrolled 61 kidney recipients from severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-infected deceased donors. Using optimal matching methods, we matched every recipient to three comparators receiving kidneys from SARS-CoV-2-negative deceased donors with otherwise highly similar characteristics in the same transplant centers to compare 6-month eGFR. RESULTS: Among recipients of SARS-CoV-2-infected donor kidneys, one recipient died with a functional graft within 6 months. Mean 6-month eGFR was not significantly different between SARS-CoV-2-infected and noninfected donor groups (55±21 and 57±25 ml/min per 1.73 m 2 , respectively; P = 0.61). Six-month eGFR in recipients from SARS-CoV-2-infected donors who died of reasons other than COVID-19 was not significantly different from those from SARS-CoV-2-negative donors (58±22 and 56±25 ml/min per 1.73 m 2 , respectively; P = 0.51). However, recipients from donors who died of COVID-19 had significantly lower 6-month eGFR than those from SARS-CoV-2-negative donors (46±17 and 58±27 ml/min per 1.73 m 2 , respectively; P = 0.03). No donor-to-recipient SARS-CoV-2 transmission was observed. CONCLUSIONS: Six-month eGFR was not significantly different between recipients of kidneys from SARS-CoV-2-infected and noninfected donors. However, those receiving kidneys from donors who died of COVID-19 had significantly lower 6-month eGFR. Donor-to-recipient SARS-CoV-2 transmission was not observed.


Assuntos
COVID-19 , Transplante de Rim , Humanos , Morte , Sobrevivência de Enxerto , Transplante de Rim/efeitos adversos , Transplante de Rim/métodos , SARS-CoV-2 , Doadores de Tecidos , Transplantados , Estados Unidos/epidemiologia , Estudos Prospectivos
9.
AJPM Focus ; 2(3): 100095, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37234692

RESUMO

Introduction: This study describes changes in the mental health, financial security, and physical activity levels of women in North Carolina during the COVID-19 pandemic. Methods: Data were collected from women aged 20-40 years receiving primary care at 2 health centers in North Carolina during 2020-2022. Surveys (N=127) evaluated changes in mental health, financial security, and physical activity during the COVID-19 pandemic. These outcomes were analyzed both descriptively and for association with sociodemographic factors using logistic regression. A subset of participants (n=46) participated in semistructured interviews. Interview transcripts were reviewed and evaluated for recurring themes by primary and secondary coders using a rapid-coding technique. Analysis was conducted in 2022. Results: Women surveyed were 28.4% non-Hispanic White, 38.6% non-Hispanic Black, and 33.1% Hispanic/Latina. Compared with reports before the pandemic, participants reported increased frustration or boredom (69.1%), loneliness (51.6%), anxiety (64.3%), depression (52.4%), and changed sleep patterns (68.3%). Increased alcohol and other recreational substance use were associated with race and ethnicity (p<0.05) after adjustment for other sociodemographic factors. Participants reported difficulty in paying for basic expenses (44.0%). Financial difficulties during COVID-19 were associated with non-Hispanic Black race and ethnicity, less education, and lower prepandemic household income. Data showed pandemic-associated reductions in mild (32.8%), moderate (39.5%), and strenuous (43.3%) exercise, with a correlation between increased depression and reduced mild exercise. Interviews identified themes including reduced activity while working remotely, lack of gym access, and reduced motivation for exercise. Conclusions: This mixed-methods study is one of the first to evaluate the mental health, financial security, and physical activity challenges women aged between 20 and 40 years in the southern U.S. faced during the COVID-19 pandemic.

10.
Ann Surg ; 277(2): e366-e375, 2023 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-34387201

RESUMO

OBJECTIVE: We sought to investigate the biological effects of pre-reperfusion treatments of the liver after warm and cold ischemic injuries in a porcine donation after circulatory death model. SUMMARY OF BACKGROUND DATA: Donation after circulatory death represents a severe form of liver ischemia and reperfusion injury that has a profound impact on graft function after liver transplantation. METHODS: Twenty donor pig livers underwent 60 minutes of in situ warm ischemia after circulatory arrest and 120 minutes of cold static preservation prior to simulated transplantation using an ex vivo perfusion machine. Four reperfusion treatments were compared: Control-Normothermic (N), Control- Subnormothermic (S), regulated hepatic reperfusion (RHR)-N, and RHR-S (n = 5 each). The biochemical, metabolic, and transcriptomic profiles, as well as mitochondrial function were analyzed. RESULTS: Compared to the other groups, RHR-S treated group showed significantly lower post-reperfusion aspartate aminotransferase levels in the reperfusion effluent and histologic findings of hepatocyte viability and lesser degree of congestion and necrosis. RHR-S resulted in a significantly higher mitochondrial respiratory control index and calcium retention capacity. Transcriptomic profile analysis showed that treatment with RHR-S activated cell survival and viability, cellular homeostasis as well as other biological functions involved in tissue repair such as cytoskeleton or cytoplasm organization, cell migration, transcription, and microtubule dynamics. Furthermore, RHR-S inhibited organismal death, morbidity and mortality, necrosis, and apoptosis. CONCLUSION: Subnormothermic RHR mitigates IRI and preserves hepatic mitochondrial function after warm and cold hepatic ischemia. This organ resuscitative therapy may also trigger the activation of protective genes against IRI. Sub- normothermic RHR has potential applicability to clinical liver transplantation.


Assuntos
Preservação de Órgãos , Transcriptoma , Suínos , Animais , Preservação de Órgãos/métodos , Fígado/patologia , Reperfusão , Isquemia , Necrose/metabolismo , Necrose/patologia
11.
Am J Surg ; 224(6): 1398-1402, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36400602

RESUMO

Debate continues as to whether choledochoduodenostomy (CDD) can be used instead of Roux-en-Y choledochojejunostomy (CDJ) when duct-to-duct (DTD) is not an option. We hypothesized that CDD and CDJ had similar rates of complications. All deceased-donor liver transplantations from September 2011 to March 2020 were categorized by biliary reconstruction. Primary outcomes were bleeding, bile leak, anastomotic stricture, and cholangitis. Of the 1,086 patients, 812 (74.8%) received a DTD; 225 (20.7%) received a CDD; and 49 (4.5%) received a CDJ. Cholangitis was significantly higher in CDJ compared to DTD and CDD (26.5% vs 6% vs 13.8%, p < 0.0001). When controlling for significant confounders, CDJ had 10.2 higher odds of cholangitis (95% CI 4.4-23.2) compared to DTD, and 3.3 higher odds compared to CDD (95% CI 1.4-7.8). When compared to DTD, CDJ and CDD had significantly lower odds of stricture. CDD continues to be a safe alternative for biliary reconstruction in deceased-donor liver transplantation.


Assuntos
Transplante de Fígado , Humanos , Ductos Biliares/cirurgia , Doadores Vivos , Anastomose em-Y de Roux , Coledocostomia
12.
Am J Physiol Gastrointest Liver Physiol ; 323(2): G126-G133, 2022 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-35700191

RESUMO

Quantitative measurement of the degree of hepatic ischemia-reperfusion injury (IRI) is crucial for developing therapeutic strategies for its treatment. We hypothesized that clearance of fluorescent dye through bile metabolism may reflect the degree of hepatic IRI. In this study, we investigated sodium fluorescein clearance kinetics in blood and bile for quantifying the degree of hepatic IRI. Warm ischemia times (WITs) of 0, 30, or 60 min followed by 1 h or 4 h of reperfusion, were applied to the median and lateral lobes of the liver in Sprague-Dawley rats. Subsequently, 2 mg/kg of sodium fluorescein was injected intravenously, and blood and bile samples were collected over 60 min to measure fluorescence intensities. The bile-to-plasma fluorescence ratios demonstrated an inverse correlation with WIT and were distinctly lower in the 60-min WIT group than in the control or 30-min WIT groups. Bile-to-plasma fluorescence ratios displayed superior discriminability for short versus long WITs when measured 1 h after reperfusion versus 4 h. We conclude that the bile-to-blood ratio of fluorescence after sodium fluorescein injection has the potential to enable the quantification of hepatic IRI severity.NEW & NOTEWORTHY Previous attempts to use fluorophore clearance to test liver function have relied on a single source of data. However, the kinetics of substrate processing via bile metabolism include decreasing levels in blood and increasing levels in bile. Thus, we analyzed data from blood and bile to better reflect fluorescein clearance kinetics.


Assuntos
Bile , Traumatismo por Reperfusão , Animais , Bile/metabolismo , Fluoresceína/metabolismo , Fluoresceína/uso terapêutico , Cinética , Fígado/metabolismo , Ratos , Ratos Sprague-Dawley , Traumatismo por Reperfusão/metabolismo
13.
Transplantation ; 106(5): 997-1003, 2022 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-34319926

RESUMO

BACKGROUND: Calcineurin inhibitor (CNI)-based immunosuppression in liver transplantation (LTx) is associated with acute and chronic deterioration of kidney function. Delaying CNI initiation by using induction rabbit antithymocyte globulin (rATG) may provide kidneys with adequate time to recover from a perioperative insult reducing the risk of early post-LTx renal deterioration. METHODS: This was an open-label, multicenter, randomized controlled clinical trial comparing use of induction rATG with delayed CNI initiation (d 10) against upfront CNI commencement (standard of care [SOC]) in those patients deemed at standard risk of postoperative renal dysfunction following LTx. The primary endpoint was change in (delta) creatinine from baseline to month 12. RESULTS: Fifty-five patients were enrolled in each study arm. Mean tacrolimus levels remained comparable in both groups from day 10 throughout the study period. A significant difference in delta creatinine was observed between rATG and SOC groups at 9 mo (P = 0.03) but not at month 12 (P = 0.05). Estimated glomerular filtration rate levels remained comparable between cohorts at all time points. Rates of biopsy-proven acute rejection at 1 y were similar between groups (16.3 versus 12.7%, P = 0.58). rATG showed no significant adverse effects. Survival at 12 mo was comparable between groups (P = 0.48). CONCLUSIONS: Although the use of induction rATG and concurrent CNI deferral in this study did not demonstrate a significant difference in delta creatinine at 1 y, these results indicate a potential role for rATG in preserving early kidney function, especially when considered with CNI deferral beyond 10 d or lower target tacrolimus levels, with acceptable safety and treatment efficacy.


Assuntos
Transplante de Rim , Transplante de Fígado , Soro Antilinfocitário/uso terapêutico , Inibidores de Calcineurina/efeitos adversos , Creatinina , Rejeição de Enxerto/prevenção & controle , Humanos , Imunossupressores/uso terapêutico , Quimioterapia de Indução , Rim , Transplante de Rim/efeitos adversos , Transplante de Fígado/efeitos adversos , Tacrolimo/uso terapêutico
14.
J Nutr ; 152(5): 1220-1227, 2022 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-34967894

RESUMO

BACKGROUND: Hot extrusion is widely used to produce iron-fortified rice, but heating may increase resistant starch and thereby decrease iron bioavailability. Cold-extruded iron-fortified rice may have higher bioavailability but has higher iron losses during cooking. Thus, warm extrusion could have nutritional benefits, but this has not been tested. Whether the addition of citric acid (CA) and trisodium citrate (TSC) counteracts any detrimental effect of high-extrusion temperature on iron bioavailability is unclear. OBJECTIVES: Our aim was to assess the effects of varying processing temperatures on the starch microstructure of extruded iron-fortified rice and resulting iron solubility and iron bioavailability. METHODS: We produced extruded iron-fortified rice grains at cold, warm, and hot temperatures (40°C, 70°C, and 90°C), with and without CA/TSC at a molar ratio of iron to CA/TSC of 1:0.3:5.5. We characterized starch microstructure using small- and wide-angle X-ray scattering and differential scanning calorimetry, assessed color over 6 mo, and measured in vitro iron solubility. In standardized rice and vegetable test meals consumed by young women (n = 22; mean age: 23 y; geometric mean plasma ferritin: 29.3 µg/L), we measured iron absorption from the fortified rice grains intrinsically labeled with 57ferric pyrophosphate (57FePP), compared with ferrous sulfate (58FeSO4) solution added extrinsically to the meals. RESULTS: Warm and hot extrusion altered starch morphology from native type A to type V and increased retrograded starch. However, extrusion temperature did not significantly affect iron solubility or iron bioavailability. The geometric mean fractional iron absorption of iron from fortified rice extruded with CA/TSC (8.2%; 95% CI: 7.9%, 11.0%) was more than twice that from extruded rice without CA/TSC (3.0%; 95% CI: 2.7%, 3.4%; P < 0.001). CONCLUSIONS: Higher extrusion temperatures did not affect iron bioavailability from extruded rice in young women, but co-extrusion of CA/TSC with FePP sharply increased iron absorption independently from extrusion temperature. This trial is registered at www.clinicaltrials.gov as NCT03703726.


Assuntos
Ferro , Oryza , Adulto , Disponibilidade Biológica , Feminino , Alimentos Fortificados , Temperatura Alta , Humanos , Isótopos , Oryza/química , Amido , Temperatura , Adulto Jovem
15.
J Med Educ Curric Dev ; 8: 23821205211051803, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34859153

RESUMO

INTRODUCTION: Physicians are looked upon to lead the healthcare team, a task that has grown increasingly complex and interdisciplinary, requiring a diverse extra-clinical skillset. Physician Executive Leadership (PEL) Plus is a student-run program that uniquely utilizes both didactic and real-world project-based approaches to deliver a business and management curriculum to medical students. METHODS: We developed and implemented PEL Plus during the 2018-19 and 2019-20 academic years, geared at first- and second-year medical students. We provide an overview of this combined didactic and project-based curriculum, in addition to evaluating if the program was efficacious in teaching the desired skillset. We assessed short-term knowledge acquisition using multiple-choice questions, and investigated student perceptions of their learning and the program using Likert scales and narrative feedback. We also investigated the influence of student demographics on performance, in order to assess the appropriateness of our target audience. RESULTS: 28 students completed PEL Plus over the two years (14 students/year). Average performance on multiple-choice questions showed statistically significant improvement after the majority of sessions. There were no statistically significant effects of demographics on performance in the majority of sessions. Students self-rated stronger understandings of lecture topics after each session, and analysis of narrative feedback demonstrated thematic categories centred on teaching style, new knowledge, lecture content/material, projects, networking, program structure, and generic statements. DISCUSSION: PEL Plus is an innovative and effective approach to teaching business, leadership, and management skills in undergraduate medical education. Development of similar programs at other institutions will positively impact the broader medical student community.

17.
J Cardiovasc Comput Tomogr ; 15(6): 477-483, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34210627

RESUMO

BACKGROUND: Coronary CT angiography (CCTA) and contrast-enhanced thoracic CT (CECT) are distinctly different diagnostic procedures that involve intravenous contrast-enhanced CT of the chest. The technical component of these procedures is reimbursed at the same rate by the Centers for Medicare and Medicaid Services (CMS). This study tests the hypothesis that the direct costs of performing these exams are significantly different. METHODS: Direct costs for both procedures were measured using a time-driven activity-based costing (TDABC) model. The exams were segmented into four phases: preparation, scanning, post-scan monitoring, and image processing. Room occupancy and direct labor times were collected for scans of 54 patients (28 CCTA and 26 CECT studies), in seven medical facilities within the USA and used to impute labor and equipment cost. Contrast material costs were measured directly. Cost differences between the exams were analyzed for significance and variability. RESULTS: Mean CCTA duration was 3.2 times longer than CECT (121 and 37 â€‹min, respectively. p â€‹< â€‹0.01). Mean CCTA direct costs were 3.4 times those of CECT ($189.52 and $55.28, respectively, p â€‹< â€‹0.01). Both labor and capital equipment costs for CCTA were significantly more expensive (6.5 and 1.8-fold greater, respectively, p â€‹< â€‹0.001). Segmented by procedural phase, CCTA was both longer and more expensive for each (p â€‹< â€‹0.01). Mean direct costs for CCTA exceeded the standard CMS technical reimbursement of $182.25 without accounting for indirect or overhead costs. CONCLUSION: The direct cost of performing CCTA is significantly higher than CECT, and thus reimbursement schedules that treat these procedures similarly undervalue the resources required to perform CCTA and possibly decrease access to the procedure.


Assuntos
Angiografia por Tomografia Computadorizada , Medicare , Idoso , Angiografia Coronária , Humanos , Valor Preditivo dos Testes , Tomografia Computadorizada por Raios X , Estados Unidos
18.
iScience ; 24(6): 102578, 2021 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-34142061

RESUMO

The design of artificial solid electrolyte interphases (ASEIs) that overcome the traditional instability of Li metal anodes can accelerate the deployment of high-energy Li metal batteries (LMBs). By building the ASEI ex situ, its structure and composition is finely tuned to obtain a coating layer that regulates Li electrodeposition, while containing morphology and volumetric changes at the electrode. This review analyzes the structure-performance relationship of several organic, inorganic, and hybrid materials used as ASEIs in academic and industrial research. The electrochemical performance of ASEI-coated electrodes in symmetric and full cells was compared to identify the ASEI and cell designs that enabled to approach practical targets for high-energy LMBs. The comparative performance and the examined relation between ASEI thickness and cell-level specific energy emphasize the necessity of employing testing conditions aligned with practical battery systems.

19.
J Biomed Opt ; 26(5)2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-34021537

RESUMO

SIGNIFICANCE: Real-time information about oxygen delivery to the hepatic graft is important to direct care and diagnose vascular compromise in the immediate post-transplant period. AIM: The current study was designed to determine the utility of visible diffuse reflectance spectroscopy (vis-DRS) for measuring liver tissue saturation in vivo. APPROACH: A custom-built vis-DRS probe was calibrated using phantoms with hemoglobin (Hb) and polystyrene microspheres. Ex vivo (extracorporeal circulation) and in vivo protocols were used in a swine model (n = 15) with validation via blood gas analysis. RESULTS: In vivo absorption and scattering measured by vis-DRS with and without biliverdin correction correlated closely between analyses. Lin's concordance correlation coefficients are 0.991 for µa and 0.959 for µs ' . Hb measured by blood test and vis-DRS with (R2 = 0.81) and without (R2 = 0.85) biliverdin correction were compared. Vis-DRS data obtained from the ex vivo protocol plotted against the PO2 derived from blood gas analysis showed a good fit for a Hill coefficient of 1.67 and P50 = 34 mmHg (R2 = 0.81). A conversion formula was developed to account for the systematic deviation, which resulted in a goodness-of-fit R2 = 0.76 with the expected oxygen dissociation curve. CONCLUSIONS: We show that vis-DRS allows for real-time measurement of liver tissue saturation, an indicator for liver perfusion and oxygen delivery.


Assuntos
Hemoglobinas , Fígado , Animais , Circulação Extracorpórea , Fígado/diagnóstico por imagem , Oxigênio , Análise Espectral , Suínos
20.
PLoS One ; 16(5): e0250518, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34033669

RESUMO

Gestational trophoblastic disease (GTD) is a heterogeneous group of lesions arising from placental tissue. Epithelioid trophoblastic tumor (ETT), derived from chorionic-type trophoblast, is the rarest form of GTD with only approximately 130 cases described in the literature. Due to its morphologic mimicry of epithelioid smooth muscle tumors and carcinoma, ETT can be misdiagnosed. To date, molecular characterization of ETTs is lacking. Furthermore, ETT is difficult to treat when disease spreads beyond the uterus. Here using RNA-Seq analysis in a cohort of ETTs and other gestational trophoblastic lesions we describe the discovery of LPCAT1-TERT fusion transcripts that occur in ETTs and coincide with underlying genomic deletions. Through cell-growth assays we demonstrate that LPCAT1-TERT fusion proteins can positively modulate cell proliferation and therefore may represent future treatment targets. Furthermore, we demonstrate that TERT upregulation appears to be a characteristic of ETTs, even in the absence of LPCAT1-TERT fusions, and that it appears linked to copy number gains of chromosome 5. No evidence of TERT upregulation was identified in other trophoblastic lesions tested, including placental site trophoblastic tumors and placental site nodules, which are thought to be the benign chorionic-type trophoblast counterpart to ETT. These findings indicate that LPCAT1-TERT fusions and copy-number driven TERT activation may represent novel markers for ETT, with the potential to improve the diagnosis, treatment, and outcome for women with this rare form of GTD.


Assuntos
1-Acilglicerofosfocolina O-Aciltransferase/genética , Células Epitelioides/patologia , Doença Trofoblástica Gestacional/etiologia , Proteínas de Fusão Oncogênica/genética , Telomerase/genética , Neoplasias Trofoblásticas/patologia , Neoplasias Uterinas/patologia , 1-Acilglicerofosfocolina O-Aciltransferase/metabolismo , Adulto , Biomarcadores Tumorais/genética , Proliferação de Células , Células Epitelioides/metabolismo , Feminino , Doença Trofoblástica Gestacional/patologia , Humanos , Pessoa de Meia-Idade , Proteínas de Fusão Oncogênica/metabolismo , Gravidez , Telomerase/metabolismo , Neoplasias Trofoblásticas/genética , Neoplasias Trofoblásticas/metabolismo , Neoplasias Uterinas/genética , Neoplasias Uterinas/metabolismo
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