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Study Design Medical vignettes. Objectives Lumbar spinal stenosis (LSS) is a degenerative condition with a high prevalence in the elderly population, that is associated with a significant economic burden and often requires spinal surgery. Prior authorization of surgical candidates is required before patients can be covered by a health plan and must be approved by medical directors (MDs), which is often subjective and clinician specific. In this study, we hypothesized that the prediction accuracy of machine learning (ML) methods regarding surgical candidates is comparable to that of a panel of MDs. Methods Based on patient demographic factors, previous therapeutic history, symptoms and physical examinations and imaging findings, we propose an ML which computes the probability of spinal surgical recommendations for LSS. The model implements a random forest model trained from medical vignette data reviewed by MDs. Sets of 400 and 100 medical vignettes reviewed by MDs were used for training and testing. Results The predictive accuracy of the machine learning model was with a root mean square error (RMSE) between model predictions and ground truth of .1123, while the average RMSE between individual MD’s recommendations and ground truth was .2661. For binary classification, the AUROC and Cohen’s kappa were .959 and .801, while the corresponding average metrics based on individual MD’s recommendations were .844 and .564, respectively. Conclusions Our results suggest that ML can be used to automate prior authorization approval of surgery for LSS with performance comparable to a panel of MDs.

A global outbreak of invasive Mycobacterium chimaera infections after cardiac surgery has recently been linked to bioaerosols from contaminated heater-cooler units. The majority of cases have occurred after valvular surgery or aortic graft surgery and nearly half have resulted in death. To date, infections in patients with left ventricular assist devices (LVADs) have not been characterized in the literature. We report two cases of device-associated M. chimaera infection in patients with continuous-flow LVADs and describe challenges related to diagnosis and management in this population.

In the professions of today are ethical concerns of no overwhelming importance? Are these concerns less important in certain professions rather than others? Do some practitioners carry a blase attitude regarding ethics within their profession?

The major anionic mitogenic polypeptide for endothelial cells, acidic fibroblast growth factor (FGF), has been purified to homogeneity from bovine brain and its complete primary structure established by gas-phase sequence analysis. The 140 amino acid (Mr 16,000) protein has been previously shown to be a potent growth factor for many diverse cell types of mesodermal origin, in vitro, and an angiogenic agent, in vivo. The amino acid sequence of bovine brain acidic FGF has a 53% absolute homology with that of bovine pituitary basic FGF suggesting that these endothelial cell mitogens are derived from a single ancestral gene.

Summary A cDNA coding for SAP-1 was isolated from a λgt11 human hepatoma expression library using polyclonal antibodies raised against human SAP-1. Three positive clones were isolated with inserts of approximately 0.3 Kb (S1.1), 2 Kb (S1.2) and 2.2 Kb (S-1.3). The latter 2 contained an internal EcoRI site. All three clones cross-hybridized with one another, indicating sequence homology. The nucleotide sequence of S-1.1 was determined. Colinearity was established between 19 amino acids obtained by sequencing the amino terminus of pure SAP-1 and 57 bp from the 5′ and of S-1.1. The open reading frame of S-1.1 coded for 67 amino acids. One glycosylation site was found 21 residues from the amino terminus, and no stop codons were found. S-1.1 codes for a mature polypeptide chain with a calculated molecular weight of 8955 daltons, corresponding to approximately 99% of mature SAP-1.

The two major mitogenic polypeptides for endothelial cells have been purified to homogeneity. The complete primary structure of bovine pituitary basic fibroblast growth factor (FGF) and the amino-terminal amino acid sequence of bovine brain acidic FGF have been established by gas-phase sequence analyses. Homogeneous preparations of these polypeptides are potent mitogens (basic FGF, ED50 approximately equal to 60 pg/ml; acidic FGF ED50 approximately equal to 6000 pg/ml) for many diverse cell types including capillary endothelial cells, vascular smooth muscle cells, and adrenocortical and granulosa cells; in vivo, basic FGF is a powerful angiogenic agent in the chick chorioallantoic membrane assay. The available protein sequence data demonstrate the existence of significant structural homology between the two polypeptides.

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