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Background: This study aims to determine the effect of time and imaging modality (three-dimensional (3D) CT vs. 3D magnetic resonance imaging (MRI)) on the surgical procedure indicated for shoulder instability. The hypothesis is there will be no clinical difference in procedure selection between time and imaging modality. Methods: Eleven shoulder surgeons were surveyed with the same ten shoulder instability clinical scenarios at three time points. All time points included history of present illness, musculoskeletal exam, radiographs, and standard two-dimensional MRI. To assess the effect of imaging modality, survey 1 included 3D MRI while survey 2 included a two-dimensional and 3D CT scan. To assess the effect of time, a retest was performed with survey 3 which was identical to survey 2. The outcome measured was whether surgeons made a “major” or “minor” surgical change between surveys. Results: The average major change rate was 14.1% (standard deviation: 7.6%). The average minor change rate was 12.6% (standard deviation: 7.5%). Between survey 1 to the survey 2, the major change rate was 15.2%, compared to 13.1% when going from the second to the third survey (P = .68). The minior change rate between the first and second surveys was 12.1% and between the second to third interview was 13.1% (P = .8). Discussion: The findings suggest that the major factor related to procedural changes was time between reviewing patient information. Furthermore, this study demonstrates that there remains significant intrasurgeon variability in selecting surgical procedures for shoulder instability. Lastly, the findings in this study suggest that 3D MRI is clinically equivalent to 3D CT in guiding shoulder instability surgical management. Conclusion: This study demonstrates that there is significant variability in surgical procedure selection driven by time alone in shoulder instability. Surgical decision making with 3D MRI was similar to 3D CT scans and may be used by surgeons for preoperative planning.

This case report highlights the development of severe, life-threatening thrombotic complications after chronic recreational use of large quantities of nitrous oxide in a 21-year-old patient. In young patients presenting with thromboembolism and nitrous oxide abuse, swift identification of symptoms and management is critical.

Background: Both restricted inverse kinematic alignment (iKA) and gap balancing aim for a balanced total knee arthroplasty by adjusting femoral component position based on ligamentous gaps. However, iKA targets a native tibial joint line vs resecting perpendicular to the mechanical axis. This study compares how these 2 techniques impact the balance and laxity throughout flexion and joint line obliquity (JLO), arithmetic hip-knee-ankle angle (aHKA), and the coronal plane alignment of the knee (CPAK). Methods: Two surgeons performed 75 robot-assisted iKA total knee arthroplasties. A digital joint tensioner collected laxity data throughout flexion before femoral resection. The femoral component position was determined using predictive gap-planning to optimize the balance throughout flexion. Planned gap balancing (pGB) simulations were performed for each case using neutral tibial resections. Mediolateral balance, laxity, and CPAK were compared among pGB, planned iKA (piKA), and final iKA. Results: Both piKA and pGB had similar mediolateral balance and laxity, with mean differences .05) between pGB and piKA. piKA recreated a more native CPAK distribution, with types I-V being the most common ones, while most pGB knees were of type V, VII, and III. Final iKA and piKA had similar mediolateral balance and laxity, with a root-mean-square error

Immunotherapy drugs are gaining popularity in the treatment of certain malignancies due to the success of these agents in recent clinical trials. Pembrolizumab is an immune checkpoint inhibitor that acts via binding to programmed cell death 1 (PD-1) receptors on T-cells, allowing for the constitutive activation of T-cells to fight malignant tumor cells. Immune checkpoint molecules such as PD-1 act to inhibit T-cell function, promoting tolerance to self-antigens. Inhibition of these molecules may lead to increased T-cell activation against cancer cells, but also against healthy tissue, leading to the side effects of these medications known as immune-related adverse events. In this article, we present the case of a 77-year-old female with a history of metastatic colonic adenocarcinoma presenting with new-onset diabetes mellitus and diabetic ketoacidosis in the setting of receiving pembrolizumab chemotherapy. Our patient was treated with hydration, insulin therapy, and management of her electrolytes, ultimately being discharged with the need for home insulin therapy to manage her new-onset diabetes. There are no current guidelines for the management or surveillance of patients receiving pembrolizumab chemotherapy, and further research should be done to determine which patients are at highest risk to developing this rare but potentially lethal side effect.

Introduction:. Annually, over 250,000 women are diagnosed with breast cancer with over one-third undergoing mastectomy and contemplating reconstruction. Surgical breast reconstructive options vary in post-operative recovery, yet with a paucity of objective data to inform women of their expected recovery after flap or implant-based reconstruction. As a result, patient decision-making is based primarily on surgeon preference and subjective data regarding perceived invasiveness of surgical options. This study aims to identify recovery outcomes of interest to breast cancer patients and to determine the feasibility of objectively measuring patient recovery after mastectomy and reconstruction using patient-worn actigraphy devices. Methods:. Three survivorship focus groups for patients after mastectomy with and without reconstruction were used to identify recovery outcomes they considered relevant. Cloud storage systems and actigraphy devices were piloted to determine performance. Actigraphy devices were worn by patients peri-operatively to measure post-operative sleep quality and steps taken, normalized to individual patient pre-operative control data. Results:. Focus groups identified sleep quality, return to activity (measurable with actigraphy), and driving as variables impacting surgical decision-making. We prospectively measured outcomes for four women undergoing immediate pre-pectoral tissue expander placement and four women undergoing immediate free flap reconstruction. Actigraphy data demonstrated an initial decrease in activity, increase in sleep variability and increased heart rate that approached the patients’ pre-operative normalized data as they recovered over time. Conclusions:. These data demonstrate that actigraphy data would be of interest to patients making breast reconstruction decisions and that the data can be successfully collected to inform decision-making.

Introduction: The International Society for Sexual Medicine (ISSM) Ad Hoc Committee for the Definition of Premature Ejaculation developed the first evidence-based definition for lifelong premature ejaculation (PE) in 2007 and concluded that there were insufficient published objective data at that time to develop a definition for acquired PE. Aim: The aim of this article is to review and critique the current literature and develop a contemporary, evidence-based definition for acquired PE and/or a unified definition for both lifelong and acquired PE. Methods: In April 2013, the ISSM convened a second Ad Hoc Committee for the Definition of Premature Ejaculation in Bangalore, India. The same evidence-based systematic approach to literature search, retrieval, and evaluation used by the original committee was adopted. Results: The committee unanimously agreed that men with lifelong and acquired PE appear to share the dimensions of short ejaculatory latency, reduced or absent perceived ejaculatory control, and the presence of negative personal consequences. Men with acquired PE are older, have higher incidences of erectile dysfunction, comorbid disease, and cardiovascular risk factors, and have a longer intravaginal ejaculation latency time (IELT) as compared with men with lifelong PE. A self-estimated or stopwatch IELT of 3 minutes was identified as a valid IELT cut-off for diagnosing acquired PE. On this basis, the committee agreed on a unified definition of both acquired and lifelong PE as a male sexual dysfunction characterized by (i) ejaculation that always or nearly always occurs prior to or within about 1 minute of vaginal penetration from the first sexual experience (lifelong PE) or a clinically significant and bothersome reduction in latency time, often to about 3 minutes or less (acquired PE); (ii) the inability to delay ejaculation on all or nearly all vaginal penetrations; and (iii) negative personal consequences, such as distress, bother, frustration, and/or the avoidance of sexual intimacy. Conclusion: The ISSM unified definition of lifelong and acquired PE represents the first evidence-based definition for these conditions. This definition will enable researchers to design methodologically rigorous studies to improve our understanding of acquired PE. Serefoglu EC, McMahon CG, Waldinger MD, Althof SE, Shindel A, Adaikan G, Becher EF, Dean J, Giuliano F, Hellstrom WJG, Giraldi A, Glina S, Incrocci L, Jannini E, McCabe M, Parish S, Rowland D, Segraves RT, Sharlip I, and Torres LO. An evidence-based unified definition of lifelong and acquired premature ejaculation: Report of the second International Society for Sexual Medicine Ad Hoc Committee for the Definition of Premature Ejaculation. Sex Med 2014;2:41–59.

Introduction: In 2009, the International Society for Sexual Medicine (ISSM) convened a select panel of experts to develop an evidence-based set of guidelines for patients suffering from lifelong premature ejaculation (PE). That document reviewed definitions, etiology, impact on the patient and partner, assessment, and pharmacological, psychological, and combined treatments. It concluded by recognizing the continually evolving nature of clinical research and recommended a subsequent guideline review and revision every fourth year. Consistent with that recommendation, the ISSM organized a second multidisciplinary panel of experts in April 2013, which met for 2 days in Bangalore, India. This manuscript updates the previous guidelines and reports on the recommendations of the panel of experts. Aim: The aim of this study was to develop clearly worded, practical, evidenced-based recommendations for the diagnosis and treatment of PE for family practice clinicians as well as sexual medicine experts. Method: A comprehensive literature review was performed. Results: This article contains the report of the second ISSM PE Guidelines Committee. It offers a new unified definition of PE and updates the previous treatment recommendations. Brief assessment procedures are delineated, and validated diagnostic and treatment questionnaires are reviewed. Finally, the best practices treatment recommendations are presented to guide clinicians, both familiar and unfamiliar with PE, in facilitating treatment of their patients. Conclusion: Development of guidelines is an evolutionary process that continually reviews data and incorporates the best new research. We expect that ongoing research will lead to a more complete understanding of the pathophysiology as well as new efficacious and safe treatments for this sexual dysfunction. We again recommend that these guidelines be reevaluated and updated by the ISSM in 4 years. Althof SE, McMahon CG, Waldinger MD, Serefoglu EC, Shindel AW, Adaikan PG, Becher E, Dean J, Giuliano F, Hellstrom WJG, Giraldi A, Glina S, Incrocci L, Jannini E, McCabe M, Parish S, Rowland D, Segraves RT, Sharlip I, and Torres LO. An update of the International Society of Sexual Medicine's guidelines for the diagnosis and treatment of premature ejaculation (PE). Sex Med 2014;2:60–90.

Short-chain fatty acid (SCFA) biosynthesis is pertinent to production of biofuels, industrial compounds, and pharmaceuticals from renewable resources. To expand on Escherichia coli SCFA products, we previously implemented a coenzyme A (CoA)-dependent pathway that condenses acetyl-CoA to a diverse group of short-chain fatty acyl-CoAs. To increase product titers and reduce premature pathway termination products, we conducted in vivo and in vitro analyses to understand and improve the specificity of the acyl-CoA thioesterase enzyme, which releases fatty acids from CoA. A total of 62 putative bacterial thioesterases, including 23 from the cow rumen microbiome, were inserted into a pathway that condenses acetyl-CoA to an acyl-CoA molecule derived from exogenously provided propionic or isobutyric acid. Functional screening revealed thioesterases that increase production of saturated (valerate), unsaturated (trans-2-pentenoate), and branched (4-methylvalerate) SCFAs compared to overexpression of E. coli thioesterase tesB or native expression of endogenous thioesterases. To determine if altered thioesterase acyl-CoA substrate specificity caused the increase in product titers, six of the most promising enzymes were analyzed in vitro. Biochemical assays revealed that the most productive thioesterases rely on promiscuous activity but have greater specificity for product-associated acyl-CoAs than for precursor acyl-CoAs. In this study, we introduce novel thioesterases with improved specificity for saturated, branched, and unsaturated short-chain acyl-CoAs, thereby expanding the diversity of potential fatty acid products while increasing titers of current products. The growing uncertainty associated with protein database annotations denotes this study as a model for isolating functional biochemical pathway enzymes in situations where experimental evidence of enzyme function is absent.

The production of mycobactin (MBT) by Mycobacterium tuberculosis is essential for this bacterium to access iron when it is in an infected host. Due to this essential function, there is considerable interest in deciphering the mechanism of MBT assembly, with the goal of targeting select biosynthetic steps for antituberculosis drug development. The proposed scheme for MBT biosynthesis involves assembly of the MBT backbone by a hybrid nonribosomal peptide synthetase (NRPS)/polyketide synthase (PKS) megasynthase followed by the tailoring of this backbone by N(6) acylation of the central l-Lys residue and subsequent N(6)-hydroxylation of the central N(6)-acyl-l-Lys and the terminal caprolactam. A complete testing of this hypothesis has been hindered by the inability to heterologously produce soluble megasynthase components. Here we show that soluble forms of the NRPS components MbtB, MbtE, and MbtF are obtained when these enzymes are coproduced with MbtH. Using these soluble enzymes we determined the amino acid specificity of each adenylation (A) domain. These results suggest that the proposed tailoring enzymes are actually involved in precursor biosynthesis since the A domains of MbtE and MbtF are specific for N(6)-acyl-N(6)-hydroxy-l-Lys and N(6)-hydroxy-l-Lys, respectively. Furthermore, the preference of the A domain of MbtB for l-Thr over l-Ser suggests that the megasynthase produces MBT derivatives with β-methyl oxazoline rings. Since the most prominent form of MBT produced by M. tuberculosis lacks this β-methyl group, a mechanism for demethylation remains to be discovered. These results suggest revisions to the MBT biosynthesis pathway while also identifying new targets for antituberculosis drug development.

Most functional metagenomic studies have been limited by the poor expression of many genes derived from metagenomic DNA in Escherichia coli, which has been the predominant surrogate host to date. To expand the range of expressed genes, we developed tools for construction and functional screening of metagenomic libraries in Streptomyces lividans. We expanded on previously published protocols by constructing a system that enables retrieval and characterization of the metagenomic DNA from biologically active clones. To test the functionality of these methods, we constructed and screened two metagenomic libraries in S. lividans. One was constructed with pooled DNA from 14 bacterial isolates cultured from Alaskan soil and the second with DNA directly extracted from the same soil. Functional screening of these libraries identified numerous clones with hemolytic activity, one clone that produces melanin by a previously unknown mechanism, and one that induces the overproduction of a secondary metabolite native to S. lividans. All bioactive clones were functional in S. lividans but not in E. coli, demonstrating the advantages of screening metagenomic libraries in more than one host.

We designed a week-long laboratory workshop in metagenomics for a cohort of undergraduate student researchers. During this course, students learned and utilized molecular biology and microbiology techniques to construct a metagenomic library from Puerto Rican soil. Pre-and postworkshop assessments indicated student learning gains in technical knowledge, skills, and confidence in a research environment. Postworkshop construction of additional libraries demonstrated retention of research techniques by the students.

Background: Gut microbiota contribute to the health of their hosts, and alterations in the composition of this microbiota can lead to disease. Previously, we demonstrated that indigenous gut bacteria were required for the insecticidal toxin of Bacillus thuringiensis to kill the gypsy moth, Lymantria dispar. B. thuringiensis and its associated insecticidal toxins are commonly used for the control of lepidopteran pests. A variety of factors associated with the insect host, B. thuringiensis strain, and environment affect the wide range of susceptibilities among Lepidoptera, but the interaction of gut bacteria with these factors is not understood. To assess the contribution of gut bacteria to B. thuringiensis susceptibility across a range of Lepidoptera we examined larval mortality of six species in the presence and absence of their indigenous gut bacteria. We then assessed the effect of feeding an enteric bacterium isolated from L. dispar on larval mortality following ingestion of B. thuringiensis toxin., Results: Oral administration of antibiotics reduced larval mortality due to B. thuringiensis in five of six species tested. These included Vanessa cardui (L.), Manduca sexta (L.), Pieris rapae (L.) and Heliothis virescens (F.) treated with a formulation composed of B. thuringiensis cells and toxins (DiPel), and Lymantria dispar (L.) treated with a cell-free formulation of B. thuringiensis toxin (MVPII). Antibiotics eliminated populations of gut bacteria below detectable levels in each of the insects, with the exception of H. virescens, which did not have detectable gut bacteria prior to treatment. Oral administration of the Gram-negative Enterobacter sp. NAB3, an indigenous gut resident of L. dispar, restored larval mortality in all four of the species in which antibiotics both reduced susceptibility to B. thuringiensis and eliminated gut bacteria, but not in H. virescens. In contrast, ingestion of B. thuringiensis toxin (MVPII) following antibiotic treatment significantly increased mortality of Pectinophora gossypiella (Saunders), which was also the only species with detectable gut bacteria that lacked a Gram-negative component. Further, mortality of P. gossypiella larvae reared on diet amended with B. thuringiensis toxin and Enterobacter sp. NAB3 was generally faster than with B. thuringiensis toxin alone., Conclusion: This study demonstrates that in some larval species, indigenous gut bacteria contribute to B. thuringiensis susceptibility. Moreover, the contribution of enteric bacteria to host mortality suggests that perturbations caused by toxin feeding induce otherwise benign gut bacteria to exert pathogenic effects. The interaction between B. thuringiensis and the gut microbiota of Lepidoptera may provide a useful model with which to identify the factors involved in such transitions.

We introduce a fast and robust technique for single-particle tracking with nanometer accuracy. We extract the center-of-mass of the image of a single particle with a simple, iterative algorithm that efficiently suppresses background-induced bias in a simplistic centroid estimator. Unlike many commonly used algorithms, our position estimator requires no prior information about the shape or size of the tracked particle image and uses only simple arithmetic operations, making it appropriate for future hardware implementation and real-time feedback applications. We demonstrate it both numerically and experimentally, using an inexpensive CCD camera to localize 190 nm fluorescent microspheres to better than 5 nm.