Structural and Functional Analysis of a β2-Adrenergic Receptor Complex with GRK5.

The phosphorylation of agonist-occupied G-protein-coupled receptors (GPCRs) by GPCR kinases (GRKs) functions to turn off G-protein signaling and turn on arrestin-mediated signaling. While a structural understanding of GPCR/G-protein and GPCR/arrestin complexes has emerged in recent years, the molecular architecture of a GPCR/GRK complex remains poorly defined. We used a comprehensive integrated approach of cross-linking, hydrogen-deuterium exchange mass spectrometry (MS), electron microscopy, mutagenesis, molecular dynamics simulations, and computational docking to analyze GRK5 interaction with the β2-adrenergic receptor (β2AR). These studies revealed a dynamic mechanism of complex formation that involves large conformational changes in the GRK5 RH/catalytic domain interface upon receptor binding. These changes facilitate contacts between intracellular loops 2 and 3 and the C terminus of the β2AR with the GRK5 RH bundle subdomain, membrane-binding surface, and kinase catalytic cleft, respectively. These studies significantly contribute to our understanding of the mechanism by which GRKs regulate the function of activated GPCRs. PAPERCLIP

Risk factors for wound infection in surgery for spinal metastasis

Wound infection rates are generally higher in patients undergoing surgery for spinal metastasis. Risk factors of wound infection in these patients are poorly understood. Purpose To identify demographic and clinical variables that may be associated with patients experiencing a higher wound infection rate. Study design Retrospective study with prospectively collected data of spinal metastasis patients operated consecutively at a University Teaching Hospital, adult spine division which is a tertiary referral centre for complex spinal surgery. Patient sample Ninety-eight patients were all surgically treated, consecutively from January 2009 to September 2011. Three patients had to be excluded due to inadequate data. Outcome measures Physiological measures, with presence or absence of microbiologically proven infection. Methods Various demographic and clinical data were recorded, including age, serum albumin level, blood total lymphocyte count, corticosteroid intake, Malnutrition Universal Screening Tool (MUST) score, neurological disability, skin closure material used, levels of surgery and administration of peri-operative corticosteroids. No funding was received from any sources for this study and as far as we are aware, there are no potential conflict of interest-associated biases in this study. Results Higher probabilities of infection were associated with low albumin level, seven or more levels of surgery, use of delayed/non-absorbable skin closure material and presence of neurological disability. Of these factors, levels of surgery were found to be statistically significant at the 5 % significance level. Conclusion Risk of infection is high (17.9 %) in patients undergoing surgery for spinal metastasis. Seven or more vertebral levels of surgery increase the risk of infection significantly (p < 0.05). Low albumin level and presence of neurological disability appear to show a trend towards increased risk of infection. Use of absorbable skin closure material, age, low lymphocyte count, peri-operative administration of corticosteroids and MUST score do not appear to influence the risk of infection

End-Effector Contact and Force Detection for Miniature Autonomous Robots Performing Lunar and Expeditionary Surgery

Introduction: The U.S. Space Force was stood up on December 20, 2019 as an independent branch under the Air Force consisting of about 16,000 active duty and civilian personnel focused singularly on space. In addition to the Space Force, the plans by NASA and private industry for exploration-class long-duration missions to the moon, near-earth asteroids, and Mars makes semi-independent medical capability in space a priority. Current practice for space-based medicine is limited and relies on a “life-raft” scenario for emergencies. Discussions by working groups on military space-based medicine include placing a Role III equivalent facility in a lunar surface station. Surgical capability is a key requirement for that facility. Materials and Methods: To prepare for the eventuality of surgery in space, it is necessary to develop low-mass, low power, mini-surgical robots, which could serve as a celestial replacement for existing terrestrial robots. The current study focused on developing semi-autonomous capability in surgical robotics, specifically related to task automation. Two categories for end-effector tissue interaction were developed: Visual feedback from the robot to detect tissue contact, and motor current waveform measurements to detect contact force. Results: Using a pixel-to-pixel deep neural network to train, we were able to achieve an accuracy of nearly 90% for contact/nocontact detection. Large torques were predicted well by a trained long short-term memory recursive network, but the technique did not predict small torques well. Conclusion: Surgical capability on long-duration missions will require human/machine teaming with semi-autonomous surgical robots. Our existing small, lightweight, low-power miniature robots perform multiple essential tasks in one design including hemostasis, fluid management, suturing for traumatic wounds, and are fully insertable for internal surgical procedures. To prepare for the inevitable eventuality of an emergency surgery in space, it is essential that automated surgical robot capabilities be developed

Evidence that regulation of intramembrane proteolysis is mediated by substrate gating during sporulation in Bacillus subtilis

© 2018 Ramírez-Guadiana et al. http://creativecommons.org/licenses/by/4.0/. During the morphological process of sporulation in Bacillus subtilis two adjacent daughter cells (called the mother cell and forespore) follow different programs of gene expression that are linked to each other by signal transduction pathways. At a late stage in development, a signaling pathway emanating from the forespore triggers the proteolytic activation of the mother cell transcription factor σK. Cleavage of pro-σK to its mature and active form is catalyzed by the intramembrane cleaving metalloprotease SpoIVFB (B), a Site-2 Protease (S2P) family member. B is held inactive by two mother-cell membrane proteins SpoIVFA (A) and BofA. Activation of pro-σK processing requires a site-1 signaling protease SpoIVB (IVB) that is secreted from the forespore into the space between the two cells. IVB cleaves the extracellular domain of A but how this cleavage activates intramembrane proteolysis has remained unclear. Structural studies of the Methanocaldococcus jannaschii S2P homolog identified closed (substrate-occluded) and open (substrate-accessible) conformations of the protease, but the biological relevance of these conformations has not been established. Here, using co-immunoprecipitation and fluorescence microscopy, we show that stable association between the membrane-embedded protease and its substrate requires IVB signaling. We further show that the cytoplasmic cystathionine-β-synthase (CBS) domain of the B protease is not critical for this interaction or for pro-σK processing, suggesting the IVB-dependent interaction site is in the membrane protease domain. Finally, we provide evidence that the B protease domain adopts both open and closed conformations in vivo. Collectively, our data support a substrate-gating model in which IVB-dependent cleavage of A on one side of the membrane triggers a conformational change in the membrane-embedded protease from a closed to an open state allowing pro-σK access to the caged interior of the protease

Perceptions of patients, physicians, and medical students on physicians’ appearance*

AbstractObjectiveTo investigate the impressions made by different styles of dress and appearance adopted by physicians on patients, medical students, and other physicians in Brazil.MethodsTwo hundred fifty nine patients, 119 students, and 99 physicians answered questions related to a panel of male and female physicians’ pictures covering the following styles: white clothing; white coat; formal coat; formal, informal, and casual garments; and surgical scrubs. They also reported their level of discomfort with a list of 20 items for professional appearance of both genders.ResultsMost of the answers of the volunteers involved using white clothes or white coat, and in many situations the percentages of preference referred for these styles were close. Physicians and students preferred physicians wearing surgical scrubs for emergency visits, and doctors with informal style for discussing psychological problems with male professionals. Patients most often chose white clothing in response to questions. Regarding male professionals, all three groups reported a high degree of discomfort for the use of shorts and bermuda shorts, multiple rings, facial piercings, sandals, extravagant hair color, long hair, and earrings. For females, high levels of discomfort were reported for shorts, blouses exposing the belly, facial piercings, multiple rings, extravagant hair color, and heavy makeup.ConclusionBrazilian patients, physicians, and medical students form a better initial impression of physicians using clothing traditionally associated with the profession and exhibiting a more conventional appearance. The use of entirely white garments appears to be a satisfactory option in this country

Impressões de pacientes, médicos e estudantes de Medicina quanto a aparência dos médicos

ResumoObjetivoInvestigar as impressões causadas em pacientes, estudantes de Medicina e médicos brasileiros por diferentes estilos de vestimenta e aparência adotados pelos médicos.MétodosParticiparam da pesquisa 259 pacientes, 119 estudantes e 99 médicos, respondendo questões relativas a um painel de fotos de médico e médica vestidos nos seguintes estilos: roupa branca, avental branco, avental social, formal, informal, casual e centro cirúrgico. Eles ainda registraram seu grau de desconforto frente uma lista de 20 itens de aparência para profissionais de ambos os sexos.ResultadoA maioria das respostas dos voluntários envolveu o uso de roupa branca ou avental branco, e em muitas questões os percentuais de preferência referidos para esses estilos foram muito próximos. Médicos e estudantes preferiram profissionais em traje de centro cirúrgico para consultas de urgência, e o estilo informal para discutir problemas psicológicos com profissional masculino. Os pacientes escolheram mais frequentemente a roupa branca em resposta às questões. No tocante aos profissionais masculinos, os três grupos referiram elevado grau de incômodo para o uso de shorts e bermudas, muitos anéis, piercing facial, sandálias, cabelos de cor extravagante, cabelos compridos e brincos. Para o sexo feminino, níveis elevados de desconforto foram assinalados para shorts, blusas mostrando a barriga, piercing facial, bermudas, muitos anéis, cabelos de cor extravagante e maquiagem carregada.ConclusãoPacientes, médicos e estudantes de Medicina brasileiros desenvolvem melhor impressão inicial de médicos que utilizam trajes tradicionalmente associados com a profissão e de aparência mais convencional. O uso da vestimenta inteiramente branca parece ser opção satisfatória no Brasil.AbstractObjectiveTo investigate the impressions made by different styles of dress and appearance adopted by physicians on patients, medical students and other physicians in Brazil.MethodsTwo hundred fifty nine patients, 119 students, and 99 physicians answered questions related to a panel of male and female physicians’ pictures covering the following styles: white clothing; white coat; formal, informal, and casual garments; and surgical scrubs. They also reported their level of discomfort with a list of 20 items for professional appearance of both genders.ResultsMost of the answers of the volunteers involved using white clothes or white coat, and in many situations the percentages of preference referred for these styles were close. Physicians and students preferred physicians wearing surgical scrubs for emergency visits, and doctors with informal style for discussing psychological problems with male professionals. Patients most often chose white clothing in response to questions. Regarding male professionals, all three groups reported high degree of discomfort for the use of shorts and bermuda shorts, multiple rings, facial piercing, sandals, extravagant hair color, long hair, and earrings. For females, high levels of discomfort were reported to shorts, blouses exposing the belly, facial piercing, multiple rings, extravagant hair color, and heavy makeup.ConclusionBrazilian patients, physicians, and medical students form a better initial impression of physicians using clothing traditionally associated with the profession and exhibiting more conventional appearance. The use of entirely white garments appears to be a satisfactory option in this country

Galaxy and Mass Assembly (GAMA): Improved emission lines measurements in four representative samples at 0.07 < z < 0.3

© ESO, 2016. This paper presents a new catalog of emission lines based on the GAMA II data for galaxies between 0.07 9.4 at z ∼ 0.1 and log M∗ > 10.6 at z ∼ 0.30. We have developed a dedicated code called MARVIN that automates the main steps of the data analysis, but imposes visual individual quality control of each measurement. We use this catalog to investigate how the sample selection influences the shape of the stellar mass - metallicity relation. We find that commonly used selection criteria on line detections and by AGN rejection could affect the shape and dispersion of the high-mass end of the M - Z relation. For log M∗ > 10.6, common selection criteria reject about 65% of the emission-line galaxies. We also find that the relation does not evolve significantly from z = 0.07 to z = 0.34 in the range of stellar mass for which the samples are representative (log M∗ > 10.6). For lower stellar masses (log M∗ < 10.2) we are able to show that the observed 0.15 dex metallicity decrease in the same redshift range is a consequence of a color bias arising from selecting targets in the r-band. We highlight that this color selection bias affects all samples selected in r-band (e.g., GAMA and SDSS), even those drawn from volume-limited samples. Previously reported evolution of the M - Z relation at various redshifts may need to be revised to evaluate the effect of this selection bias

Looking backward: From Euler to Riemann

We survey the main ideas in the early history of the subjects on which Riemann worked and that led to some of his most important discoveries. The subjects discussed include the theory of functions of a complex variable, elliptic and Abelian integrals, the hypergeometric series, the zeta function, topology, differential geometry, integration, and the notion of space. We shall see that among Riemann's predecessors in all these fields, one name occupies a prominent place, this is Leonhard Euler. The final version of this paper will appear in the book \emph{From Riemann to differential geometry and relativity} (L. Ji, A. Papadopoulos and S. Yamada, ed.) Berlin: Springer, 2017

Accounting Problems Under the Excess Profits Tax

DNA vaccines based on subunits from pathogens have several advantages over other vaccine strategies. DNA vaccines can easily be modified, they show good safety profiles, are stable and inexpensive to produce, and the immune response can be focused to the antigen of interest. However, the immunogenicity of DNA vaccines which is generally quite low needs to be improved. Electroporation and co-delivery of genetically encoded immune adjuvants are two strategies aiming at increasing the efficacy of DNA vaccines. Here, we have examined whether targeting to antigen-presenting cells (APC) could increase the immune response to surface envelope glycoprotein (Env) gp120 from Human Immunodeficiency Virus type 1 (HIV- 1). To target APC, we utilized a homodimeric vaccine format denoted vaccibody, which enables covalent fusion of gp120 to molecules that can target APC. Two molecules were tested for their efficiency as targeting units: the antibody-derived single chain Fragment variable (scFv) specific for the major histocompatilibility complex (MHC) class II I-E molecules, and the CC chemokine ligand 3 (CCL3). The vaccines were delivered as DNA into muscle of mice with or without electroporation. Targeting of gp120 to MHC class II molecules induced antibodies that neutralized HIV-1 and that persisted for more than a year after one single immunization with electroporation. Targeting by CCL3 significantly increased the number of HIV-1 gp120-reactive CD8(+) T cells compared to non-targeted vaccines and gp120 delivered alone in the absence of electroporation. The data suggest that chemokines are promising molecular adjuvants because small amounts can attract immune cells and promote immune responses without advanced equipment such as electroporation.Funding Agencies|Research Council of Norway; Odd Fellow</p