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result(s) for
"Conaway, Mark R."
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Standardizing Prostaglandin Initiation in Prenatally Diagnosed Ductal-Dependent Neonates; A Quality Initiative
by
Dean, Peter N.
,
Conaway, Mark R.
,
Haughey, Brena S.
in
Algorithms
,
Alprostadil - therapeutic use
,
Apnea - chemically induced
2023
Prostaglandin E1 (PGE) is used in patients with ductal-dependent congenital heart disease (CHD). Side effects of apnea and fever are often dose dependent and occur within 48 h after initiation. We initiated a standardized approach to PGE initiation after our institution recognized a high incidence of side effects and a wide variety of starting doses of PGE. Neonates with prenatally diagnosed ductal-dependent CHD were identified, started on a standardized protocol that started PGE at 0.01 mcg/kg/min, and evaluated for PGE related side effects. Compliance, outcomes and dose adjustments during the first 48 h post-PGE initiation were evaluated. Fifty patients were identified (25 pre-intervention; 25 post-intervention). After intervention, compliance with the protocol was 96%, and apnea or fever occurred in 28% (compared to 63% pre-intervention,
p
= 0.015). Dose adjustments (either increase or decrease) prior to cardiac surgery were similar in both cohorts (60%, 52%,
p
= 0.569). There were no mortalities or emergent procedures performed due to ductus arteriosus closure. Standardizing a protocol for initiating PGE in prenatally diagnosed ductal-dependent CHD was successful and reduced the incidence of apnea, fever, and sepsis evaluations. A starting dose of 0.01 mcg/kg/min did not cause increased adverse effects.
Journal Article
Percutaneous Injuries before and after the Needlestick Safety and Prevention Act
by
Conaway, Mark R
,
Phillips, Elayne K
,
Jagger, Janine C
in
Employees
,
Federal regulation
,
Humans
2012
According to this analysis of needlestick injuries in a sample of U.S. hospitals before and after passage of the NSPA in 2000, the number of percutaneous injuries per 100 full-time hospital employees declined after enactment of the legislation.
To the Editor:
The Needlestick Safety and Prevention Act (NSPA) (HR.5178) was signed into law on November 6, 2000.
1
It required employers to provide safety-engineered devices to employees who are at risk for exposure to bloodborne pathogens, to include frontline workers in selecting these devices, to review exposure-control plans at least annually to ensure that they reflect advances in sharps-safety technology, and to maintain sharps-injury logs that specify required details about the injury. The NSPA also mandated that the Occupational Safety and Health Administration (OSHA) revise the Bloodborne Pathogens Standard in 2001, incorporating these requirements.
2
To determine whether the NSPA . . .
Journal Article
Dose-finding design for multi-drug combinations
by
O'Quigley, John
,
Conaway, Mark R
,
Wages, Nolan A
in
Antineoplastic Combined Chemotherapy Protocols - toxicity
,
Bayes Theorem
,
Chemotherapy
2011
Background
Most of the current designs used for Phase I dose finding trials in oncology
will either involve only a single cytotoxic agent or will impose some implicit
ordering among the doses. The goal of the studies is to estimate the maximum
tolerated dose (MTD), the highest dose that can be administered with an acceptable
level of toxicity. A key working assumption of these methods is the monotonicity of
the dose–toxicity curve.
Purpose
Here we consider situations in which the monotonicity assumption may fail.
These studies are becoming increasingly common in practice, most notably, in phase I
trials that involve combinations of agents. Our focus is on studies where there exist
pairs of treatment combinations for which the ordering of the probabilities of a
dose-limiting toxicity cannot be known a priori.
Methods
We describe a new dose-finding design which can be used for multiple-drug
trials and can be applied to this kind of problem. Our methods proceed by laying out
all possible orderings of toxicity probabilities that are consistent with the known
orderings among treatment combinations and allowing the continual reassessment method
(CRM) to provide efficient estimates of the MTD within these orders. The design can
be seen to simplify to the CRM when the full ordering is known.
Results
We study the properties of the design via simulations that provide
comparisons to the Bayesian approach to partial orders (POCRM) of Wages, Conaway, and
O'Quigley. The POCRM was shown to perform well when compared to other suggested
methods for partial orders. Therefore, we comapre our approach to it in order to
assess the performance of the new design.
Limitations
A limitation concerns the number of possible orders. There are dose-finding
studies with combinations of agents that can lead to a large number of possible
orders. In this case, it may not be feasible to work with all possible orders.
Conclusions
The proposed design demonstrates the ability to effectively estimate MTD
combinations in partially ordered dosefinding studies. Because it relaxes the
monotonicity assumption, it can be considered a multivariate generalization of the
CRM. Hence, it can serve as a link between single and multiple-agent dosefinding
trials.
Journal Article
Collateral status, hyperglycemia, and functional outcome after acute ischemic stroke
by
Bruno, Askiel
,
Williams, Alana
,
Southerland, Andrew M.
in
Analysis
,
Angiography
,
Blood Glucose
2022
Background
Mixed data exist regarding the association between hyperglycemia and functional outcome after acute ischemic stroke when accounting for the impact of leptomeningeal collateral flow. We sought to determine whether collateral status modifies the association between treatment group and functional outcome in a subset of patients with large vessel occlusion enrolled in the Stroke Hyperglycemia Insulin Network Effort (SHINE) trial.
Methods
In this post-hoc analysis, we analyzed patients enrolled into the SHINE trial with anterior circulation large vessel occlusion who underwent imaging with CT angiography prior to glucose control treatment group assignment. The primary analysis assessed the degree to which collateral status modified the effect between treatment group and functional outcome as defined by the 90-day modified Rankin Scale score. Logistic regression was used to model the data, with adjustments made for thrombectomy status, age, post-perfusion thrombolysis in cerebral infarction (TICI) score, tissue plasminogen activator (tPA) use, and baseline National Institutes of Health Stroke Scale (NIHSS) score. Five SHINE trial centers contributed data for this analysis. Statistical significance was defined as a
p
-value < 0.05.
Results
Among the 1151 patients in the SHINE trial, 57 with angiographic data were included in this sub-analysis, of whom 19 had poor collaterals and 38 had good collaterals. While collateral status had no effect (
p
= 0.855) on the association between glucose control treatment group and functional outcome, patients with good collaterals were more likely to have a favorable functional outcome (
p
= 0.001, OR 5.02; 95% CI 1.37–16.0).
Conclusions
In a post-hoc analysis using a subset of patients with angiographic data enrolled in the SHINE trial, collateral status did not modify the association between glucose control treatment group and functional outcome. However, consistent with prior studies, there was a significant association between good collateral status and favorable outcome in patients with large vessel occlusion stroke.
Trial registration
ClinicalTrials.gov
Identifier is NCT01369069. Registration date is June 8, 2011.
Journal Article
Looking past PD-L1: expression of immune checkpoint TIM-3 and its ligand galectin-9 in cervical and vulvar squamous neoplasia
by
Curley, Jacob
,
Conaway, Mark R.
,
Stoler, Mark
in
13/51
,
692/699/67/1517/1371
,
692/699/67/1857
2020
Immunotherapies targeting the PD-1/PD-L1 pathway have shown some success in cervical and vulvar squamous cell carcinomas, but little is known about the potential vulnerability of these tumors to other checkpoint inhibitors. TIM-3 is a checkpoint molecule that exerts immunosuppressive function via its interaction with Gal-9. TIM-3 and Gal-9 have been identified on a variety of malignancies but have not been studied in cervical and vulvar cancers, nor has their relationship to PD-L1 been established. Sixty-three cervical and vulvar invasive (
n
= 34) and intraepithelial lesions (
n
= 29) were assessed for TIM-3, Gal-9, and PD-L1 in tumor/lesional cells and associated immune cells. Tumoral TIM-3 expression was identified in 85% of squamous cell carcinomas but only 21% of intraepithelial lesions (
p
< 0.0001). When immune cells were also accounted for, 97% of invasive and 41% of intraepithelial lesions had a TIM-3 combined positive score (CPS) ≥ 1 (
p
< 0.0001). Tumoral membranous expression of Gal-9 was seen in 82% of squamous cell carcinomas and 31% of intraepithelial lesions (
p
= 0.0001); nearly all cases had Gal-9-positive immune cells. Tumoral PD-L1 was seen in 71% of squamous cell carcinomas and 10% of intraepithelial lesions (
p
< 0.0001), while the PD-L1 CPS was ≥1 in 82 and 21%, respectively (
p
< 0.0001). There were no significant differences in TIM-3, GAL-9, or PD-L1 expression in cervical vs. vulvar neoplasms, nor was HPV status significantly associated with any of the three markers. Dual TIM-3/Gal-9 expression was present in the majority (86%) of PD-L1-positive cases including 100% of PD-L1-positive squamous cell carcinomas, suggesting a possible role for TIM-3 checkpoint inhibition in concert with anti-PD-1/PD-L1.
Journal Article
Continual Reassessment Method for Partial Ordering
by
O'Quigley, John
,
Conaway, Mark R.
,
Wages, Nolan A.
in
Antineoplastic Agents - therapeutic use
,
Antineoplastic Agents - toxicity
,
BIOMETRIC METHODOLOGY
2011
Much of the statistical methodology underlying the experimental design of phase 1 trials in oncology is intended for studies involving a single cytotoxic agent. The goal of these studies is to estimate the maximally tolerated dose, the highest dose that can be administered with an acceptable level of toxicity. A fundamental assumption of these methods is monotonicity of the dose–toxicity curve. This is a reasonable assumption for single‐agent trials in which the administration of greater doses of the agent can be expected to produce dose‐limiting toxicities in increasing proportions of patients. When studying multiple agents, the assumption may not hold because the ordering of the toxicity probabilities could possibly be unknown for several of the available drug combinations. At the same time, some of the orderings are known and so we describe the whole situation as that of a partial ordering. In this article, we propose a new two‐dimensional dose‐finding method for multiple‐agent trials that simplifies to the continual reassessment method (CRM), introduced by O'Quigley, Pepe, and Fisher (1990, Biometrics 46, 33–48), when the ordering is fully known. This design enables us to relax the assumption of a monotonic dose–toxicity curve. We compare our approach and some simulation results to a CRM design in which the ordering is known as well as to other suggestions for partial orders.
Journal Article
Follow-up of Acute kidney injury in Neonates during Childhood Years (FANCY): a prospective cohort study
by
Conaway, Mark R.
,
Charlton, Jennifer R.
,
Pope, Chelsea F.
in
Acute Kidney Injury - epidemiology
,
Acute Kidney Injury - urine
,
Acute renal failure
2017
Background
Very low birth weight (VLBW) neonates commonly experience acute kidney injury (AKI) in the neonatal intensive care unit (NICU). We hypothesize that VLBW neonates exposed to AKI in the NICU might be at a higher risk of renal dysfunction during childhood.
Methods
In this cohort study, VLBW children (aged 3–7 years) completed a kidney health evaluation and were stratified according to AKI status in the NICU. The primary outcome was renal dysfunction defined as any of the following: estimated glomerular filtration rate (eGFR) <90 mL/min/1.73 m
2
, urine protein/creatinine >0.2 or blood pressure ≥95th percentile.
Results
Thirty-four subjects completed the study. Twenty subjects had a history of neonatal AKI (stage 1,
n
= 8; stage 2,
n
= 9; and stage 3,
n
= 3). At a median age of 5 years, the AKI group had a higher risk of renal dysfunction compared with the group without AKI (65% vs 14%, relative risk 4.5 (1.2–17.1),
p
= 0.01). Overall, 26% of the total cohort had an eGFR <90 mL/min/1.73 m
2
using serum cystatin C (35% of AKI subjects, 14% of no AKI subjects,
p
= 0.25).
Conclusions
Evidence of renal dysfunction in neonates born VLBW can be found early in childhood. Further work is necessary to determine how to reduce renal disease in this vulnerable population.
Journal Article
Growth and development in children born very low birthweight
2016
ObjectiveTo examine the relationships between growth (birth to age 2 years) and developmental outcomes in children born with very low birthweight (VLBW).DesignMotor and mental development in children born with VLBW were regressed on anthropometric measurements at birth, 9 months and 2 years using multivariable regression.SettingThe Early Childhood Longitudinal Study—Birth Cohort, a longitudinal cohort, community sample, designed to be representative of children born across the USA.Patients950 children born with VLBW (<1500 g).Main Outcome MeasuresMotor and cognitive scores on the Bayley Scales at 9 months and 24 months chronological age.ResultsA high proportion of children exhibited poor growth, with length-for-age z-scores <−2 (ie, stunting) in 21.3% of children at 9 months (adjusted for prematurity) and 34.2% of children at 2 years. Compared with children having z-scores >−2, children with growth shortfalls in head circumference, length and weight had a higher adjusted OR (aOR) of low Bayley motor scores at 9 months and 2 years (aOR ranging from 1.8 to 3.3, all p<0.05), while low Bayley cognitive scores were predicted by 9-month deficits in length and weight (aOR 2.0 and 2.4, respectively, both p<0.01) and 2-year deficits in length and head circumference (aOR 2.9 and 2.8, both p<0.05).ConclusionAnthropometric measures of growth were linked to current and future neurodevelopmental outcomes in children born with VLBW. While careful length measures may be a particularly useful marker, deficits in all anthropometric measures were risk factors for developmental delays.
Journal Article
Construction and preliminary evaluation of the inpatient glycemic control questionnaire (IGCQ): a survey tool assessing perceptions and knowledge of resident physicians
by
Conaway, Mark R.
,
Darji, Monika
,
Thigpen, S. Calvin
in
Assessment and evaluation of admissions
,
Biometry
,
Biostatistics
2019
Background
Uncontrolled hyperglycemia in hospitalized patients, with or without diabetes mellitus, is associated with many adverse outcomes. Resident physicians are the primary managers of inpatient glycemic control (IGC) in many academic and community medical centers; however, no validated survey tools related to their perceptions and knowledge of IGC are currently available. As identification of common barriers to successful IGC amongst resident physicians may help foster better educational interventions (ultimately leading to improvements in IGC and patient care), we sought to construct and preliminarily evaluate such a survey tool.
Methods
We developed the IGC questionnaire (IGCQ) by using previously published but unvalidated survey tools related to physician perspectives on inpatient glycemic control as a framework. We administered the IGCQ to a cohort of resident physicians from the University of Mississippi Medical Center, University of Louisville, Emory University, and the University of Virginia. We then used classical test theory and Rasch Partial Credit Model analyses to preliminarily evaluate and revise the IGCQ. The final survey tool contains 16 total items and three answer-choice categories for most items.
Results
Two hundred forty-six of 438 (56.2%) eligible resident physicians completed the IGCQ during various phases of development.
Conclusions
We constructed and preliminarily evaluated the IGCQ, a survey tool that may be useful for future research into resident physician perceptions and knowledge of IGC. Future studies could seek to externally validate the IGCQ and then utilize the survey tool in pre- and post-intervention assessments.
Journal Article
Regadenoson for the treatment of COVID-19: A five case clinical series and mouse studies
2023
Adenosine inhibits the activation of most immune cells and platelets. Selective adenosine A2A receptor (A2AR) agonists such as regadenoson (RA) reduce inflammation in most tissues, including lungs injured by hypoxia, ischemia, transplantation, or sickle cell anemia, principally by suppressing the activation of invariant natural killer T (iNKT) cells. The anti-inflammatory effects of RA are magnified in injured tissues due to induction in immune cells of A2ARs and ecto-enzymes CD39 and CD73 that convert ATP to adenosine in the extracellular space. Here we describe the results of a five patient study designed to evaluate RA safety and to seek evidence of reduced cytokine storm in hospitalized COVID-19 patients.
Five COVID-19 patients requiring supplemental oxygen but not intubation (WHO stages 4-5) were infused IV with a loading RA dose of 5 μg/kg/h for 0.5 h followed by a maintenance dose of 1.44 μg/kg/h for 6 hours, Vital signs and arterial oxygen saturation were recorded, and blood samples were collected before, during and after RA infusion for analysis of CRP, D-dimer, circulating iNKT cell activation state and plasma levels of 13 proinflammatory cytokines. RA was devoid of serious side effects, and within 24 hours from the start of infusion was associated with increased oxygen saturation (93.8 ± 0.58 vs 96.6 ± 1.08%, P<0.05), decreased D-dimer (754 ± 17 vs 518 ± 98 ng/ml, P<0.05), and a trend toward decreased CRP (3.80 ± 1.40 vs 1.98 ± 0.74 mg/dL, P = 0.075). Circulating iNKT cells, but not conventional T cells, were highly activated in COVID-19 patients (65% vs 5% CD69+). RA infusion for 30 minutes reduced iNKT cell activation by 50% (P<0.01). RA infusion for 30 minutes did not influence plasma cytokines, but infusion for 4.5 or 24 hours reduced levels of 11 of 13 proinflammatory cytokines. In separate mouse studies, subcutaneous RA infusion from Alzet minipumps at 1.44 μg/kg/h increased 10-day survival of SARS-CoV-2-infected K18-hACE2 mice from 10 to 40% (P<0.001).
Infused RA is safe and produces rapid anti-inflammatory effects mediated by A2A adenosine receptors on iNKT cells and possibly in part by A2ARs on other immune cells and platelets. We speculate that iNKT cells are activated by release of injury-induced glycolipid antigens and/or alarmins such as IL-33 derived from virally infected type II epithelial cells which in turn activate iNKT cells and secondarily other immune cells. Adenosine released from hypoxic tissues, or RA infused as an anti-inflammatory agent decrease proinflammatory cytokines and may be useful for treating cytokine storm in patients with Covid-19 or other inflammatory lung diseases or trauma.
Journal Article