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Organ procurement organizations (OPOs) face increasing regulatory scrutiny, and the performance of predictive models used to assess OPO performance is critical. We sought to determine whether adding deceased donor physiological and critical care data to the existing Scientific Registry of Transplant Recipients (SRTR) heart yield model would improve the model's performance. Donor data and heart transplanted (yes/no), the outcome of interest, were obtained from the United Network for Organ Sharing Donor Management Goal (DMG) Registry for 19 141 donors after brain death, from 25 OPOs. The data were split into training and testing portions. Multivariable LASSO regression was used to develop a statistical model incorporating DMG data elements with the existing components of the SRTR model. The DMG + SRTR and SRTR models were applied to the test data to compare the predictive performance of the models. The sensitivity (84%-86%) and specificity (84%-86%) were higher for the DMG + SRTR model compared to the SRTR model (71%-75% and 76%-77%, respectively). For the DMG + SRTR model, the C-statistic was 0.92 to 0.93 compared to 0.80 to 0.81 for the SRTR model. DMG data elements improve the predictive performance of the heart yield model. The addition of DMG data elements to the Organ Procurement and Transplantation Network data collection requirements should be considered., Competing Interests: Declaration of competing interest The authors of this manuscript have no conflicts of interest to disclose as described by the American Journal of Transplantation., (Published by Elsevier Inc.)

Current risk-adjusted models for donor lung use and lung graft survival do not include donor critical care data. We sought to identify modifiable donor physiologic and mechanical ventilation parameters that predict donor lung use and lung graft survival. This is a prospective observational study of donors after brain death (DBDs) managed by 19 Organ Procurement Organizations from 2016 to 2019. Demographics, mechanical ventilation parameters, and critical care data were recorded at standardized time points during donor management. The lungs were transplanted from 1811 (30%) of 6052 DBDs. Achieving ≥7 critical care endpoints was a positive predictor of donor lung use. After controlling for recipient factors, donor blood pH positively predicted lung graft survival (OR 1.48 per 0.1 unit increase in pH) and the administration of dopamine during donor management negatively predicted lung graft survival (OR 0.19). Tidal volumes ≤8 ml/kg predicted body weight (OR 0.65), and higher positive end-expiratory pressures (OR 0.91 per cm H 2 O) predicted decreased donor lung use without affecting lung graft survival. A randomized clinical trial is needed to inform optimal ventilator management strategies in DBDs., (© 2021 The American Society of Transplantation and the American Society of Transplant Surgeons.)

Background: Fusobacterium nucleatum (Fn), a bacterium associated with a wide spectrum of infections, has emerged as a key microbe in colorectal carcinogenesis. However, the underlying mechanisms and clinical relevance of Fn in colorectal cancer (CRC) remain incompletely understood., Patients and Methods: We examined associations between Fn abundance and clinicopathologic characteristics among 105 treatment-naïve CRC patients enrolled in the international, prospective ColoCare Study. Electronic medical charts, including pathological reports, were reviewed to document clinicopathologic features. Quantitative real-time polymerase chain reaction (PCR) was used to amplify/detect Fn DNA in preoperative fecal samples. Multinomial logistic regression was used to analyze associations between Fn abundance and patient sex, age, tumor stage, grade, site, microsatellite instability, body mass index (BMI), alcohol consumption, and smoking history. Cox proportional hazards models were used to investigate associations of Fn abundance with overall survival in adjusted models., Results: Compared to patients with undetectable or low Fn abundance, patients with high Fn abundance (n = 22) were 3-fold more likely to be diagnosed with rectal versus colon cancer (odds ratio [OR] = 3.01; 95% confidence interval [CI], 1.06-8.57; P = .04) after adjustment for patient sex, age, BMI, and study site. Patients with high Fn abundance also had a 5-fold increased risk of being diagnosed with rectal cancer versus right-sided colon cancer (OR = 5.32; 95% CI, 1.23-22.98; P = .03). There was no statistically significant association between Fn abundance and overall survival., Conclusion: Our findings suggest that Fn abundance in fecal samples collected prior to surgery varies by tumor site among treatment-naïve CRC patients. Overall, fecal Fn abundance may have diagnostic and prognostic significance in the clinical management of CRC., (Copyright © 2021. Published by Elsevier Inc.)

Proper regulation of the Wingless/Wnt signaling pathway is essential for normal development. The scaffolding protein Axin plays a key role in this process through interactions with Drosophila Shaggy and Armadillo. In the current studies, we used a yeast two-hybrid assay to identify ten amino acids in Axin that are critical for in vitro interaction with Shaggy and two for interaction with Armadillo. We then generated five Axin variants in which individual putative contact amino acids were mutated and compared their activity, as assayed by rescue of axin null mutant flies, to that of Axin lacking the entire Shaggy (AxinDeltaSgg) or Armadillo (AxinDeltaArm) binding domain. Although we expected these mutants to function identically to Axin in which the entire binding domain was deleted, we instead observed a spectrum of phenotypic rescue. Specifically, two point mutants within the Shaggy binding domain showed loss of activity similar to that of AxinDeltaSgg and dominantly interfered with complex function, whereas a third mutant allele, AxinK446E, retained most function. Two Axin point mutants within the Armadillo binding domain were weak alleles and retained most function. These findings demonstrate the importance of in vivo verification of the role of specific amino acids within a protein.

Objective: This study aimed to develop a protocol to screen and monitor patients with diabetic macular thickening using optical coherence tomography (OCT), a technique for high-resolution cross-sectional imaging of the retina., Design: A cross-sectional pilot study was conducted., Participants: A total of 182 eyes of 107 patients with diabetic retinopathy, 55 eyes from 31 patients with diabetes but no ophthalmoscopic evidence of retinopathy, and 73 eyes from 41 healthy volunteers were studied., Intervention: Six optical coherence tomograms were obtained in a radial spoke pattern centered on the fovea. Retinal thickness was computed automatically from each tomogram at a total of 600 locations throughout the macula. Macular thickness was displayed geographically as a false-color topographic map and was reported numerically as averages in each of nine regions., Main Outcome Measures: Correlation of OCT with slit-lamp biomicroscopy, fluorescein angiography, and visual acuity was measured., Results: Optical coherence tomography was able to quantify the development and resolution of both foveal and extrafoveal macular thickening. The mean +/- standard deviation foveal thickness was 174 +/- 18 microns in normal eyes, 179 +/- 17 microns in diabetic eyes without retinopathy, and 256 +/- 114 microns in eyes with nonproliferative diabetic retinopathy. Foveal thickness was highly correlated among left and right eyes of normal eyes (mean +/- standard deviation difference of 6 +/- 9 microns). Foveal thickness measured by OCT correlated with visual acuity (r2 = 0.79). A single diabetic eye with no slit-lamp evidence of retinopathy showed abnormal foveal thickening on OCT., Conclusions: Optical coherence tomography was a useful technique for quantifying macular thickness in patients with diabetic macular edema. The topographic mapping protocol provided geographic information on macular thickness that was intuitive and objective.

Objective: To evaluate optical coherence tomography (OCT), a novel noncontact and noninvasive imaging technique, for the diagnosis and quantitative characterization of epiretinal membranes., Methods: Optical coherence tomography is similar to an ultrasound B-scan, except that light rather than sound is used, which enables higher resolution. Over a 2-year period, OCT was used to examine 186 eyes of 160 patients who had a diagnosis of an epiretinal membrane. Optical coherence tomograms were correlated with visual acuity, slit-lamp biomicroscopy, fluorescein angiography, and funds photography., Results: Based on OCT, the epiretinal membrane was clearly separated from the retina with focal points of attachment in 49 eyes and globally adherent (no observed separation) in 125 eyes. Globally adherent membranes were associated with the following features: macular pseudohole (32 eyes), a difference in optical reflectivity between the membrane and retina (65 eyes), and/or a visible membrane tuft or edge (92 eyes). The membrane was undetectable on OCT in 12 eyes. The membrane thickness (mean +/- standard deviation) was 61 +/- 28 microns in the 169 eyes in which the thickness could be measured with OCT. Mean central macular thickness measured with OCT correlated with visual acuity (R2 = 0.73)., Conclusion: Optical coherence tomography was able to provide a structural assessment of the macula that was useful in the preoperative and postoperative evaluation of epiretinal membrane surgery. Quantitative measurements and the assessment of membrane adherence with OCT may be useful in characterizing the surgical prognosis of eyes with an epiretinal membrane.

Purpose: Optical coherence tomography (OCT) is a new technology that uses near-infrared light in an interferometer to produce approximately 10-microns resolution cross-sectional images of the tissue of interest. The authors performed repeated quantitative assessment of nerve fiber layer thickness in individuals with normal and glaucomatous eyes, and they evaluated the reproducibility of these measurements., Methods: The authors studied 21 eyes of 21 subjects by OCT. Each subject underwent five repetitions of a series of scans on five separate occasions within a 1-month period. Each series consisted of three circular scans around the optic nerve head (diameters, 2.9, 3.4, and 4.5 mm). Each series was performed separately using internal (fixation with same eye being studied) and external (fixation with contralateral eye) fixation techniques. The eye studied and the sequence of testing were assigned randomly., Results: Internal fixation (IF), in general, provides a slightly higher degree of reproducibility than external fixation (EF). Reproducibility was better in a given eye on a given visit than from visit to visit. Reproducibility as measured by intraclass correlation coefficients were as follows: circle diameter (CD), 2.9 mm, 0.51/0.57 (normal/glaucoma) (IF), 0.43/0.54 (EF); CD, 3.4 mm, 0.56/0.52 (IF), 0.43/0.61 (EF); CD, 4.5 mm, 0.53/0.43 (IF), 0.42/0.49 (EF)., Conclusions: Nerve fiber layer thickness can be reproducibly measured using OCT. Internal is superior to external fixation; each circle diameter tested provides adequate reproducibility.

Objective: The authors used optical coherence tomography (OCT), a new technique for cross-sectional imaging of the retina, to morphologically study eyes with nonexudative and exudative age-related macular degeneration (AMD). In patients with untreated exudative AMD, OCT was compared with fluorescein angiography in the identification and classification of choroidal neovascularization (CNV)., Methods: Optical coherence tomography imaging is analogous to ultrasound, except that the use of light rather than sound enables higher longitudinal resolution with a noncontact and noninvasive measurement. Optical coherence tomography was performed on 391 patients with the clinical diagnosis of AMD and was compared with conventional clinical examination to establish the cross-sectional morphology of different lesions and to develop a classification scheme for CNV. Optical coherence tomograms and fluorescein angiograms then were reviewed and correlated independently in 90 eyes of 86 patients who had exudative AMD without previous laser treatment., Results: Pigmentary changes, soft drusen, and detachments of the neurosensory retina and retinal pigment epithelium all had distinct presentations on OCT. Subretinal and intraretinal fluid caused changes in retinal thickness or elevation that could be quantified directly from the images. Choroidal neovascularization was evident in the tomograms as a thickening and fragmentation of a reflective layer, which corresponded to the retinal pigment epithelium and choriocapillaris. Changes in the reflection from this layer were observed during the progression of neovascularization, and after laser photocoagulation treatment. Classic CNV consistently presented with well-defined boundaries on OCT, whereas occult CNV had a variable cross-sectional appearance., Conclusions: Optical coherence tomography was useful in quantitatively evaluating subretinal and intraretinal fluid, assessing possible subfoveal involvement of neovascularization, and in monitoring CNV before and after laser photocoagulation. Optical coherence tomography was unable to detect CNV beneath serous pigment epithelial detachments. Optical coherence tomography may have potential in accurately defining the boundaries in a subset of angiographically occult CNV.

Purpose: To assess the potential of a new diagnostic technique called optical coherence tomography (OCT) for diagnosing and monitoring macular holes. This technique is a novel noninvasive, noncontact imaging modality that produces high longitudinal resolution (10-micron) cross-sectional tomographs of ocular tissue., Methods: Optical coherence tomography is analogous to ultrasound except that optical rather than acoustic reflectivity is measured. Cross-sectional tomographs of the retina profiling optical reflectivity in a thin, optical slice of tissue are obtained with a longitudinal resolution of 10 microns. Optical coherence tomography was used to examine 49 patients with the clinical diagnosis of idiopathic full-thickness macular hole, impending macular hole, epimacular membrane with macular pseudohole, or partial-thickness hole. The resulting OCTs were correlated with contact lens and slit-lamp biomicroscopy, fundus photography, and fluorescein angiography., Results: The cross-sectional view produced by OCT was effective in distinguishing full-thickness macular holes from partial-thickness holes, macular pseudoholes, and cysts. Optical coherence tomography was successful in staging macular holes and provided a quantitative measure of hole diameter and the amount of surrounding macular edema. Optical coherence tomography also was used to evaluate the vitreoretinal interface in patients' fellow eyes and was able to detect small separations of the posterior hyaloid from the retina., Conclusion: Optical coherence tomography appears potentially useful as a new, noninvasive, diagnostic technique for visualizing and quantitatively characterizing macular holes and assessing fellow eyes of patients with a macular hole. The tomographic information provided by OCT eventually may lead to a better understanding of the pathogenesis of macular hole formation.

Background/purpose: To assess the potential of a new diagnostic technique called optical coherence tomography for imaging macular disease. Optical coherence tomography is a novel noninvasive, noncontact imaging modality which produces high depth resolution (10 microns) cross-sectional tomographs of ocular tissue. It is analogous to ultrasound, except that optical rather than acoustic reflectivity is measured., Methods: Optical coherence tomography images of the macula were obtained in 51 eyes of 44 patients with selected macular diseases. Imaging is performed in a manner compatible with slit-lamp indirect biomicroscopy so that high-resolution optical tomography may be accomplished simultaneously with normal ophthalmic examination. The time-of-flight delay of light backscattered from different layers in the retina is determined using low-coherence interferometry. Cross-sectional tomographs of the retina profiling optical reflectivity versus distance into the tissue are obtained in 2.5 seconds and with a longitudinal resolution of 10 microns., Results: Correlation of fundus examination and fluorescein angiography with optical coherence tomography tomographs was demonstrated in 12 eyes with the following pathologies: full- and partial-thickness macular hole, epiretinal membrane, macular edema, intraretinal exudate, idiopathic central serous chorioretinopathy, and detachments of the pigment epithelium and neurosensory retina., Conclusion: Optical coherence tomography is potentially a powerful tool for detecting and monitoring a variety of macular diseases, including macular edema, macular holes, and detachments of the neurosensory retina and pigment epithelium.