Publications by authors named "John R Tuttle"

11 Publications

  • Page 1 of 1

The relationship of shoulder elevation strength to patient-reported outcome after anatomic total shoulder arthroplasty.

J Shoulder Elbow Surg 2020 Nov 9;29(11):2406-2416. Epub 2020 Jun 9.

Carilion Clinic, Virginia Tech Carilion School of Medicine, Roanoke, VA, USA. Electronic address:

Background: Most patient-reported outcome measures (PROMs) used to assess outcomes after anatomic total shoulder arthroplasty (aTSA) focus on pain and function. Although strength is considered an important component of function, only the Constant-Murley score (CMS) includes an objective measurement of shoulder strength. The purpose of this study was to evaluate the relationship between shoulder elevation strength (SES) and PROMs after aTSA for the treatment of primary glenohumeral osteoarthritis (GHOA).

Methods: This was a retrospective analysis of 605 patients enrolled in a multicenter clinical database who underwent aTSA to treat primary GHOA. Patients were evaluated preoperatively and at 24 months after surgery. Outcome was assessed with the CMS, American Shoulder and Elbow Surgeons score, Western Ontario Osteoarthritis of the Shoulder score, Single Assessment Numeric Evaluation score, and patient satisfaction. Relationships between SES and outcomes were investigated.

Results: The correlations between SES and the PROMs before and after treatment were very weak and weak, respectively (r ≤ 0.262 for all). The strength of the correlations between the absolute and adjusted CMS and the other PROMs varied from weak to moderate (r = 0.180 to r = 0.455), and the strength of the correlations was greater postoperatively. With the strength component removed from the CMS, the correlations between the CMS and other PROMs were stronger (r = 0.194 to r = 0.495).

Conclusions: Although measurement of SES provides objective information about shoulder function and outcome related to the treatment of primary GHOA with aTSA, the actual relevance to patients is unclear as the correlations between SES and PROMs were weak. Furthermore, the variable correlations between the CMS and PROMs call into question the exclusive use of the CMS and support the use of other PROMs that may more accurately reflect patient perception of outcome.
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http://dx.doi.org/10.1016/j.jse.2020.03.009DOI Listing
November 2020

Hemophilic Arthropathy.

Orthopedics 2017 Nov 30;40(6):e940-e946. Epub 2017 Jun 30.

The musculoskeletal manifestations of hemophilia A and B are some of the most common presenting symptoms and continue to be challenging to practitioners. Hemophilic arthropathy, if not initially adequately treated and managed, may lead to debilitating disease and eventually require the consideration of major surgery, including total joint arthroplasty. Thorough comprehension of the pathophysiology, diagnosis, and both medical and surgical interventions is critical in establishing an appropriate treatment regimen for these patients. Furthermore, a true multidisciplinary approach involving hematology, orthopedics, and physical therapy is essential for a patient with hemophilic arthropathy. The authors present a comprehensive review of hemophilic arthropathy from an orthopedist's perspective. [Orthopedics. 2017; 40(6):e940-e946.].
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http://dx.doi.org/10.3928/01477447-20170619-05DOI Listing
November 2017

Modifications to a LATE MERISTEM IDENTITY1 gene are responsible for the major leaf shapes of Upland cotton (Gossypium hirsutum L.).

Proc Natl Acad Sci U S A 2017 01 20;114(1):E57-E66. Epub 2016 Dec 20.

Department of Crop and Soil Sciences, North Carolina State University, Raleigh, NC 27695-7620;

Leaf shape varies spectacularly among plants. Leaves are the primary source of photoassimilate in crop plants, and understanding the genetic basis of variation in leaf morphology is critical to improving agricultural productivity. Leaf shape played a unique role in cotton improvement, as breeders have selected for entire and lobed leaf morphs resulting from a single locus, okra (l-D), which is responsible for the major leaf shapes in cotton. The l-D locus is not only of agricultural importance in cotton, but through pioneering chimeric and morphometric studies, it has contributed to fundamental knowledge about leaf development. Here we show that an HD-Zip transcription factor homologous to the LATE MERISTEM IDENTITY1 (LMI1) gene of Arabidopsis is the causal gene underlying the l-D locus. The classical okra leaf shape allele has a 133-bp tandem duplication in the promoter, correlated with elevated expression, whereas an 8-bp deletion in the third exon of the presumed wild-type normal allele causes a frame-shifted and truncated coding sequence. Our results indicate that subokra is the ancestral leaf shape of tetraploid cotton that gave rise to the okra allele and that normal is a derived mutant allele that came to predominate and define the leaf shape of cultivated cotton. Virus-induced gene silencing (VIGS) of the LMI1-like gene in an okra variety was sufficient to induce normal leaf formation. The developmental changes in leaves conferred by this gene are associated with a photosynthetic transcriptomic signature, substantiating its use by breeders to produce a superior cotton ideotype.
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http://dx.doi.org/10.1073/pnas.1613593114DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5224360PMC
January 2017

Avoiding disaster in the management of dislocated hip hemiarthroplasties: case presentation, diagnosis, and management.

Am J Emerg Med 2017 03 5;35(3):521.e3-521.e7. Epub 2016 Oct 5.

Department of Orthopaedics, Brown University Alpert School of Medicine, Providence, RI, Island.

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http://dx.doi.org/10.1016/j.ajem.2016.10.006DOI Listing
March 2017

Effects of Tranexamic Acid Cytotoxicity on In Vitro Chondrocytes.

Am J Orthop (Belle Mead NJ) 2015 Dec;44(12):E497-502

Department of Orthopaedics, Brown University Alpert School of Medicine, Providence, RI.

Use of topical tranexamic acid (TXA) in orthopedic surgery has been expanding over the past decade, with increasing evidence confirming reductions in perioperative blood loss and transfusion requirements, but there is minimal evidence regarding effects of TXA on native cartilage. We conducted a study to understand the in vitro effects of TXA on bovine cartilage and murine chondrocytes and ultimately to expand the clinical application of topical TXA to include scenarios with retained native cartilage, such as hemiarthroplasty. Bovine cartilage explants were exposed to TXA at a concentration of 100 mg/mL, and glycosaminoglycan (GAG) release and cell viability were measured at 8, 24, and 48 hours. Monolayer murine chondrocytes were exposed to TXA 25, 50, and 100 mg/mL, and viability was measured at 8, 24, and 48 hours. GAG released from bovine explants was significantly higher in the samples exposed to TXA 100 mg/mL at all time points. Cell viability was significantly decreased in the explants exposed to TXA 24 and 48 hours after initial incubation. Bovine chondrocyte viability was not affected by TXA 25 mg/mL. Murine chondrocyte viability was similar between the TXA 25 mg/mL and control samples at all time points. The TXA 50 mg/mL sample dropped from 66.51% viability at 8 hours to 6.81% viability at 24 hours and complete cell death by 48 hours. The TXA 100 mg/mL samples had no observable viable cells at 8, 24, and 48 hours. Our data indicated that TXA 100 mg/mL damaged and was cytotoxic to bovine explanted cartilage and was cytotoxic to murine chondrocytes. Murine and bovine chondrocyte viability were not affected by TXA 25 mg/mL.
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December 2015

Metabolomic and transcriptomic insights into how cotton fiber transitions to secondary wall synthesis, represses lignification, and prolongs elongation.

BMC Genomics 2015 Jun 27;16:477. Epub 2015 Jun 27.

Department of Crop Science, North Carolina State University, Raleigh, NC, 27695, USA.

Background: The morphogenesis of single-celled cotton fiber includes extreme elongation and staged cell wall differentiation. Designing strategies for improving cotton fiber for textiles and other uses relies on uncovering the related regulatory mechanisms. In this research we compared the transcriptomes and metabolomes of two Gossypium genotypes, Gossypium barbadense cv Phytogen 800 and G. hirsutum cv Deltapine 90. When grown in parallel, the two types of fiber developed similarly except for prolonged fiber elongation in the G. barbadense cultivar. The data were collected from isolated fibers between 10 to 28 days post anthesis (DPA) representing: primary wall synthesis to support elongation; transitional cell wall remodeling; and secondary wall cellulose synthesis, which was accompanied by continuing elongation only in G. barbadense fiber.

Results: Of 206 identified fiber metabolites, 205 were held in common between the two genotypes. Approximately 38,000 transcripts were expressed in the fiber of each genotype, and these were mapped to the reference set and interpreted by homology to known genes. The developmental changes in the transcriptomes and the metabolomes were compared within and across genotypes with several novel implications. Transitional cell wall remodeling is a distinct stable developmental stage lasting at least four days (18 to 21 DPA). Expression of selected cell wall related transcripts was similar between genotypes, but cellulose synthase gene expression patterns were more complex than expected. Lignification was transcriptionally repressed in both genotypes. Oxidative stress was lower in the fiber of G. barbadense cv Phytogen 800 as compared to G. hirsutum cv Deltapine 90. Correspondingly, the G. barbadense cultivar had enhanced capacity for management of reactive oxygen species during its prolonged elongation period, as indicated by a 138-fold increase in ascorbate concentration at 28 DPA.

Conclusions: The parallel data on deep-sequencing transcriptomics and non-targeted metabolomics for two genotypes of single-celled cotton fiber showed that a discrete developmental stage of transitional cell wall remodeling occurs before secondary wall cellulose synthesis begins. The data showed how lignification can be transcriptionally repressed during secondary cell wall synthesis, and they implicated enhanced capacity to manage reactive oxygen species through the ascorbate-glutathione cycle as a positive contributor to fiber length.
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http://dx.doi.org/10.1186/s12864-015-1708-9DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4482290PMC
June 2015

Virus-induced gene silencing of fiber-related genes in cotton.

Methods Mol Biol 2015 ;1287:219-34

Department of Crop Science, North Carolina State University, Box 7620, Raleigh, NC, 27695-7620, USA.

Virus-Induced Gene Silencing (VIGS) is a useful method for transient downregulation of gene expression in crop plants. The geminivirus Cotton leaf crumple virus (CLCrV) has been modified to serve as a VIGS vector for persistent gene silencing in cotton. Here the use of Green Fluorescent Protein (GFP) is described as a marker for identifying silenced tissues in reproductive tissues, a procedure that requires the use of transgenic plants. Suggestions are given for isolating and cloning combinations of target and marker sequences so that the total length of inserted foreign DNA is between 500 and 750 bp. Using this strategy, extensive silencing is achieved with only 200-400 bp of sequence homologous to an endogenous gene, reducing the possibility of off-target silencing. Cotyledons can be inoculated using either the gene gun or Agrobacterium and will continue to show silencing throughout fruit and fiber development. CLCrV is not transmitted through seed, and VIGS is limited to genes expressed in the maternally derived seed coat and fiber in the developing seed. This complicates the use of GFP as a marker for VIGS because cotton fibers must be separated from unsilenced tissue in the seed to determine if they are silenced. Nevertheless, fibers from a large number of seeds can be rapidly screened following placement into 96-well plates. Methods for quantifying the extent of silencing using semiquantitative RT-PCR are given.
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http://dx.doi.org/10.1007/978-1-4939-2453-0_16DOI Listing
November 2015

Dual-camera technique for arthroscopic rotator cuff repair.

Arthrosc Tech 2014 Dec 3;3(6):e647-51. Epub 2014 Nov 3.

Department of Orthopaedics, Brown University Alpert School of Medicine, Providence, Rhode Island, U.S.A.

An all-arthroscopic rotator cuff repair demands a high level of technical skill and is associated with a steep learning curve. It is well accepted that small rotator cuff tears or partial tears can be more difficult than large or even massive tears to repair. Part of the reason is the difficulty in visualizing the tear, as well as important surrounding structures, during repair. To improve visibility during the repair process, we have introduced a second arthroscopic camera. Two cameras allow the surgeon to observe the rotator cuff from both the articular and bursal sides. We find this technique has merit in small or partial-thickness rotator cuff tears; however, there may be other applications.
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http://dx.doi.org/10.1016/j.eats.2014.08.001DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4314554PMC
December 2014

Cost benefit analysis of topical tranexamic acid in primary total hip and knee arthroplasty.

J Arthroplasty 2014 Aug 3;29(8):1512-5. Epub 2014 Feb 3.

Department of Orthopaedics, Brown University Alpert School of Medicine, Providence, Rhode Island.

The purpose of this study was to provide a cost-benefit analysis of topical tranexamic acid (TXA) in primary total hip and knee arthroplasty patients. A retrospective cohort of 591 consecutive patients, 311 experimental and 280 control, revealed a transfusion rate reduction from 17.5% to 5.5%, increased postoperative hemoglobin, and decreased delta hemoglobin without an increase in adverse events (all P < 0.001). This led to saving $83.73 per patient based on transfusion costs alone after accounting for the cost of TXA. Hospital disposition to home compared to subacute nursing facility was also significantly increased by 9.3% (P < 0.02). We conclude that topical TXA reduces transfusion rate, increases home disposition, and reduces cost in primary hip and knee arthroplasty.
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http://dx.doi.org/10.1016/j.arth.2014.01.031DOI Listing
August 2014

Cotton fiber: a powerful single-cell model for cell wall and cellulose research.

Front Plant Sci 2012 21;3:104. Epub 2012 May 21.

Department of Crop Science, North Carolina State University, Raleigh, NC, USA.

Cotton fibers are single-celled extensions of the seed epidermis. They can be isolated in pure form as they undergo staged differentiation including primary cell wall synthesis during elongation and nearly pure cellulose synthesis during secondary wall thickening. This combination of features supports clear interpretation of data about cell walls and cellulose synthesis in the context of high throughput modern experimental technologies. Prior contributions of cotton fiber to building fundamental knowledge about cell walls will be summarized and the dynamic changes in cell wall polymers throughout cotton fiber differentiation will be described. Recent successes in using stable cotton transformation to alter cotton fiber cell wall properties as well as cotton fiber quality will be discussed. Futurec prospects to perform experiments more rapidly through altering cotton fiberwall properties via virus-induced gene silencing will be evaluated.
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http://dx.doi.org/10.3389/fpls.2012.00104DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3356883PMC
August 2012

Geminivirus-mediated gene silencing from Cotton leaf crumple virus is enhanced by low temperature in cotton.

Plant Physiol 2008 Sep 11;148(1):41-50. Epub 2008 Jul 11.

Department of Plant Biology, North Carolina State University, Raleigh, North Carolina 27606, USA.

A silencing vector for cotton (Gossypium hirsutum) was developed from the geminivirus Cotton leaf crumple virus (CLCrV). The CLCrV coat protein gene was replaced by up to 500 bp of DNA homologous to one of two endogenous genes, the magnesium chelatase subunit I gene (ChlI) or the phytoene desaturase gene (PDS). Cotyledons of cotton cultivar 'Deltapine 5415' bombarded with the modified viral vectors manifested chlorosis due to silencing of either ChlI or PDS in approximately 70% of inoculated plants after 2 to 3 weeks. Use of the green fluorescence protein gene showed that replication of viral DNA was restricted to vascular tissue and that the viral vector could transmit to leaves, roots, and the ovule integument from which fibers originate. Temperature had profound effects on vector DNA accumulation and the spread of endogenous gene silencing. Consistent with reports that silencing against viruses increases at higher temperatures, plants grown at a 30 degrees C/26 degrees C day/night cycle had a greater than 10-fold reduction in viral DNA accumulation compared to plants grown at 22 degrees C/18 degrees C. However, endogenous gene silencing decreased at 30 degrees C/26 degrees C. There was an approximately 7 d delay in the onset of gene silencing at 22 degrees C/18 degrees C, but silencing was extensive and persisted throughout the life of the plant. The extent of silencing in new growth could be increased or decreased by changing temperature regimes at various times following the onset of silencing. Our experiments establish the use of the CLCrV silencing vector to study gene function in cotton and show that temperature can have a major impact on the extent of geminivirus-induced gene silencing.
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http://dx.doi.org/10.1104/pp.108.123869DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2528111PMC
September 2008
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