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2.
Ecol Evol ; 14(4): e11213, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38571806

ABSTRACT

The giant sequoia, a serotinous conifer naturally occurring in mixed-conifer forests of the southern and central Sierra Nevada, California, USA, is the world's largest tree species. Giant sequoia reproduction has been severely lacking over the past century, due to fire exclusion, creating a significant conservation threat. Previous research on postfire sequoia reproduction in high-severity fire areas, relative to low- and moderate-severity areas, is limited. At 6 years postfire, we investigated giant sequoia reproduction in a high-severity fire area, and nearby low-/mixed-severity fire areas, in the Nelder Grove, which burned in 2017 in the Railroad fire. Postfire giant sequoia reproduction was positively correlated with fire severity in terms of density, height (growth), and proportion (relative to other conifer species), and sequoia seedling/sapling density was positively correlated with percent shrub cover. There was no correlation between distance to live sequoia seed source and density of sequoia reproduction. More research is needed in other mixed-severity fire areas, with larger high-severity fire patches, to determine whether a similar postfire response occurs elsewhere.

3.
Ann Thorac Surg ; 2024 Apr 19.
Article in English | MEDLINE | ID: mdl-38642820

ABSTRACT

Since the development of the first heart allocation system in 1988 to the most recent heart allocation system in 2018, the road to heart transplantation has continued to evolve. Policies were shaped with advances in temporary and durable left ventricular assist devices as well as prioritization of patients based on degree of illness. Herein, we review the changes in the heart allocation system over the past several decades and the impact of practice patterns across the United States.

4.
ASAIO J ; 2024 Mar 27.
Article in English | MEDLINE | ID: mdl-38531093

ABSTRACT

The physiologic impact of pulsatile flow (PF) on end-organ perfusion during cardiopulmonary bypass (CPB) is controversial. Using an intra-aortic balloon pump (IABP) to maintain PF during CPB for patients undergoing heart transplantation (HT) may impact end-organ perfusion, with implications for postoperative outcomes. A single-center retrospective study of 76 patients bridged to HT with IABP was conducted between January 2018 and December 2022. Beginning in May 2022, patients received IABP-generated PF during CPB at an internal rate of 80 beats/minute. Fifty-eight patients underwent HT with the IABP turned off (IABP-Off), whereas 18 patients underwent HT with IABP-generated PF (IABP-On). The unmatched IABP-On group experienced shorter organ ischemia times (180 vs. 203 minutes, p = 0.015) and CPB times (104 vs. 116 minutes, p = 0.022). The cohort was propensity matched according to age, organ ischemia time, and CPB time. Elevations in postoperative lactates in the immediate (2.8 vs. 1.5, p = 0.062) and 24 hour (4.7 vs. 2.4, p = 0.084) postoperative periods trended toward significance in the matched IABP-Off group. There was no difference in postoperative vasoactive inotropic score (VIS), postoperative creatinine, or length of stay. This limited preliminary data suggest that maintaining counterpulsation to generate PF during CPB may improve end-organ perfusion in this patient population as suggested by lower postoperative lactate levels.

5.
JTCVS Open ; 17: 55-63, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38420551

ABSTRACT

Background: The use of rapid-deployment valves (RDVs) has been shown to reduce the operative time for surgical aortic valve replacement (AVR). Long-term core laboratory-adjudicated data are scarce, however. Here we report final 7-year data on RDV use. Methods: TRANSFORM was a prospective, nonrandomized, multicenter, single-arm trial implanting a stented bovine pericardial valve with an incorporated balloon-expandable sealing frame. A prior published 1-year analysis included 839 patients from 29 centers. An additional 46 patients were enrolled and implanted, for a total of 885 patients. Annual clinical and core laboratory-adjudicated echocardiographic outcomes were collected through 8 years. Primary endpoints were structural valve deterioration (SVD), all-cause reintervention, all-cause valve explantation, and all-cause mortality. Secondary endpoints included hemodynamic performance assessed by echocardiography. The mean duration of follow-up was 5.0 ± 2.0 years. Results: The mean patient age was 73.3 ± 8.2 years. Isolated AVR was performed in 62.1% of the patients, and AVR with concomitant procedures was performed in 37.9%. Freedom from all-cause mortality at 7 years was 76.0% for isolated AVR and 68.2% for concomitant AVR. Freedom from SVD, all-cause reintervention, and valve explantation at 7 years was 97.5%, 95.7%, and 97.8%, respectively. The mean gradient and effective orifice area at 7 years were 11.1 ± 5.3 mm Hg and 1.6 ± 0.3 cm2, respectively. Paravalvular leak at 7 years was none/trace in 88.6% and mild in 11.4%. In patients undergoing isolated AVR, the cumulative probability of pacemaker implantation was 13.9% at 30 days, 15.5% at 1 year, and 21.8% at 7 years. Conclusions: AVR for aortic stenosis using an RDV is associated with low rates of late adverse events. This surgical pericardial tissue platform provides excellent and stable hemodynamic performance through 7 years.

6.
JTCVS Tech ; 22: 23-27, 2023 Dec.
Article in English | MEDLINE | ID: mdl-38152165

ABSTRACT

Objective: Totally endoscopic intracardiac robotic surgery is generally limited to uncomplicated mitral valve surgery. With experience, our team has developed a more aggressive approach to robotic cardiac surgery that allows for repair of a broad spectrum of mitral valve pathologies. We report complex subvalvular procedural advancements associated with this approach secondary to enhanced team experience and capabilities. Methods: All robotic mitral procedures performed by a 2-surgeon team in a quaternary care medical center from July 2011 to May 2022 were reviewed. Natural language-processing techniques were used to analyze operative reports for subvalvular repair techniques. Complex subvalvular techniques included papillary muscle repositioning, division of secondary anterior leaflet chordae, septal myomectomy, division of aberrant left ventricular muscle band attachments, and left ventricular patch reconstruction. The surgical experience was divided into 2 periods: early robotic experience (pre-2018) versus late (2018 onwards). Baseline demographics, outcomes, and subvalvular techniques were analyzed and compared. Results: A total of 1287 intracardiac robotic operations were performed by a 2-surgeon team. Thirty-day mortality was 0.6% (8/1287). Mitral valve repair was performed in 1024 patients. The mean age was 61 years (range, 18-90 years), and 15% were >75 years old; 29 patients (2.8%) had previously undergone cardiac surgery. There was a significant increase with experience in the application of advanced subvalvular techniques between the early versus late period (52.3% [268/512] vs 74.2% [380/512] (P < .001)). Conclusions: An experienced 2-surgeon team can perform progressively more complex robotic subvalvular repair techniques. These subvalvular techniques are a surrogate for team proficiency and capabilities.

8.
JTCVS Open ; 16: 1004-1007, 2023 Dec.
Article in English | MEDLINE | ID: mdl-38204665

ABSTRACT

Objective: Chest tubes are frequently placed after thymectomy, without data to support this common practice. We report our experience in eliminating them after robotic thymectomy. Methods: This is a retrospective database review of patients who underwent robotic thymectomy performed by a single surgeon in which intraoperative chest tube insertion was not planned. Patient characteristics and postoperative outcomes are presented. Results: Between January 2018 and October 2022, 75 patients underwent robotic thymectomy performed by a single surgeon. Of those, 64 (85.3%) underwent a left-sided thoracic approach. The most common indication for resection was a suspicious anterior mediastinal mass. There were no conversions to an open operation. The median operative time was 72 minutes (range, 38-164 minutes), and the median estimated blood loss was 20 cc (range, 10-60 cc). Ten patients (13.3%) went home on the day of surgery, and all others (86.7%) were discharged on postoperative day 1. A chest tube was placed in 1 patient at time of closure because of a persistent air leak after extensive adhesiolysis from a prior thoracotomy; the tube was removed on the day of surgery after resolution of the air leak. No other patient required chest tube placement intraoperatively, immediately postoperatively, or within 60 days postoperation. Two patients underwent outpatient thoracentesis within 1 month postoperation for effusions. There were no 30- or 90-day mortality and no major morbidities. Conclusions: A chest tube after robotic thymectomy is not necessary in almost all patients and can be safely omitted. The dogmatic routine practice of chest tube placement should be questioned.

9.
Behav Anal Pract ; 13(1): 217-225, 2020 Mar.
Article in English | MEDLINE | ID: mdl-32231983

ABSTRACT

The functional analysis (FA) methodology was developed to provide an empirical basis for understanding the reinforcers contributing to the maintenance of problem behavior. Previous research has demonstrated that multiple formats have been established to address some areas, such as practicality, efficiency, and safety. We reviewed the research on a new replication and extension of the standard FA format, the interview-informed synthesized contingency analysis (IISCA) and its subsequent treatment. We discuss the efficiency and effectiveness of the IISCA across various populations, settings, topographies of problem behaviors, and maintaining functions across 17 studies. Common treatment trends, novel developments, and other critical intervention components are also reviewed. We provide suggestions for future directions and guidelines for practitioners when considering the use of the IISCA.

10.
Am J Intellect Dev Disabil ; 124(5): 450-469, 2019 09.
Article in English | MEDLINE | ID: mdl-31512946

ABSTRACT

Individuals diagnosed with intellectual and developmental disabilities (IDD) frequently exhibit self-injurious behavior (SIB). Previous research has examined the published literature on behavioral treatments of SIB from 1964-2000. Results suggested that these treatments were highly efficacious at decreasing SIB, particularly when based on the results of a functional assessment. The purpose of this review is to update, replicate, and extend the previous research. The current findings indicate an increase in studies reporting automatically maintained SIB as well as less efficacious treatments overall. Discussion of our conclusions and methods of SIB assessment and treatment are discussed, both as they relate to the previous review and for future directions.


Subject(s)
Behavior Therapy/statistics & numerical data , Developmental Disabilities/complications , Intellectual Disability/complications , Self-Injurious Behavior/etiology , Self-Injurious Behavior/therapy , Adolescent , Adult , Child , Child, Preschool , Humans , Infant , Young Adult
11.
ACS Appl Bio Mater ; 2(11): 4966-4977, 2019 Nov 18.
Article in English | MEDLINE | ID: mdl-35021496

ABSTRACT

Alzheimer's disease (AD) is a protein misfolding disease commonly characterized by neuritic amyloid plaques and proteinaceous fibrillar aggregate deposits composed of ß-amyloid (Aß) aggregates. The dynamic aggregation of Aß forms toxic, nanoscale aggregate species which proceed from oligomers to fibrils. Currently, there is need for rapid and direct detection of Aß peptide aggregation and interaction with lipid membranes, as detecting an interaction with various lipid environments will provide insights to better understand how interactions may modulate membrane function on cellular surfaces, leading to the progression of AD. The goal of this study was to utilize a colorimetric, biomimetic, vesicle-binding assay as a biosensor to detect and investigate the occurrence of neurodegenerative disease-associated protein aggregation and interaction with lipid membranes. Lipid/polydiacetylene (PDA) vesicles were exposed to monomeric preparations of Wild Type Aß(1-40) or point mutations in Aß with amino acid substitutions that are commonly associated with familial AD (E22G Arctic, E22Q Dutch, A21G Flemish, D23N Iowa, and E22K Italian). We investigated how these substitutions affect Aß(1-40) aggregation and interaction with lipid vesicles designed to mimic biological membranes. Time-resolved colorimetric measurements were obtained and reveal that exposure to lipid/PDA vesicle biosensors results in the direct detection of mutant Aß(1-40) peptide-lipid interaction events. Aß(1-40) peptide aggregate membrane activity varies among Aß peptide variants and lipid composition. In addition, we used atomic force microscopy and Thioflavin T fluorescence assays to distinguish the stages of Aß(1-40) aggregate formation, morphology, and membrane activity. These studies provide a simple means of aggregate detection and insight into the role of cellular surfaces in the mechanism of AD aggregation.

12.
Behav Anal ; 34(1): 103-10, 2011.
Article in English | MEDLINE | ID: mdl-22532734

ABSTRACT

A task force authorized by the Executive Council of the Association for Behavior Analysis International (ABAI) generated the statement below concerning the techniques called restraint and seclusion. Members of the task force independently reviewed the scientific literature concerning restraint and seclusion and agreed unanimously to the content of the statement. The Executive Council accepted the statement, and it was subsequently approved by a two-thirds majority vote of the general membership. It now constitutes official ABAI policy. The position statement is posted on the ABAI Web site (www.abainternational.org/ABA/statements/RestraintSeclusion.asp). The purpose of the position statement is to provide guidance to behavior analysts and other professionals interested in the position of ABAI on these controversial topics. In extreme cases, abuses of procedures erroneously used in the name of behavior analysis are not defensible. On the other hand, behavior analysts acting ethically and in good faith are provided with guidelines for sound and acceptably safe practice. To the extent that behavior-analytic positions influence public policy and law, this statement can be presented to officials and lawmakers to guide informed decision making. At the conclusion of the document, a bibliography is provided of articles and presentations considered by one or more task force members in developing the position statement.

13.
Nature ; 466(7305): 435, 2010 Jul 22.
Article in English | MEDLINE | ID: mdl-20651670
14.
Behav Anal Pract ; 2(1): 53-8, 2009.
Article in English | MEDLINE | ID: mdl-22477697

ABSTRACT

The evolution of the field of applied behavior analysis to a practice-oriented profession has created the need to ensure that the consumers of these services are adequately protected. We review the limitations of the current board certification process and present a rationale for the establishment of licensing standards for applied behavior analysts on a state-by-state basis. Recommendations for securing the passage of a licensure bill also are discussed.

15.
Gene ; 309(1): 49-56, 2003 Apr 24.
Article in English | MEDLINE | ID: mdl-12727357

ABSTRACT

As genome sequences of many organisms - including humans - are being decoded, there is a great need for genetic tools to analyze newly discovered genes/proteins. A 'unigenic evolution' approach has been previously proposed for dissecting protein domains, which is based on the assumption that functionally important regions of a protein may tolerate missense mutations less well than other regions. We describe a unigenic evolution analysis of general transcription factor IIB (TFIIB) - a protein that is well characterized both structurally and functionally - to better understand the molecular basis of this genetic approach. The overall distribution profile of hypomutable regions within yeast TFIIB correlates extremely well with the known compact structural domains, suggesting that the unigenic evolution approach can help reveal structural properties of a protein. We further show that a small region located immediately carboxyl-terminal to the zinc ribbon motif is functionally important despite its strong hypermutability. Our study further demonstrates the usefulness of the unigenic evolution approach in dissecting protein domains, but suggests that the mutability of different regions of a protein in such a test is determined primarily by their structural properties.


Subject(s)
Evolution, Molecular , Saccharomyces cerevisiae Proteins/genetics , Transcription Factor TFIIB/genetics , Amino Acid Sequence , Binding Sites/genetics , Escherichia coli/genetics , Glutathione Transferase/genetics , Glutathione Transferase/metabolism , Molecular Sequence Data , Mutagenesis , Mutation , Protein Binding , RNA Polymerase II/metabolism , Recombinant Fusion Proteins/genetics , Recombinant Fusion Proteins/metabolism
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