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A 45-year-old Female with an Atypical Presentation of Pharyngitis
Introduction: Emergency physicians are trained to treat a variety of ailments in the emergency department (ED), some of which are emergent, while others are not. A common complaint seen in the ED is a sore throat. While most sore throats are easily diagnosed and treated, less common causes are often not considered in the differential diagnoses. Therefore, the purpose of this case study was to present an atypical case of sore throat and discuss differential diagnoses.Case Presentation: The patient was a 45-year-old female who presented to the ED with a three-day history of sore throat that was exacerbated by eating and drinking. The patient was not on any prescription medications, but tried over-the-counter medications for the sore throat without any improvement in symptoms. Review of systems was positive for sore throat, fevers, and chills. Physical examination of her oropharynx revealed mildly dry mucous membranes with confluent plaques and white patchy ulcerative appearance involving the tongue, tonsils, hard palate, and soft palate. Rapid streptococcal antigen, mononucleosis spot test, and KOH test were performed and found to be negative.Discussion: After initial testing was negative, a follow-up complete blood count with differential and complete metabolic profile were ordered. The patient was found to have decreased lymphocytes and platelets. Based upon those results, a diagnosis was made in the ED, the patient was started on medication, and further laboratory workup was ordered to confirm the diagnosis. ED providers should consider non-infectious as well as infectious causes for a sore throat, as this might lead to a diagnosis of an underlying condition
The proteasome lid triggers COP9 signalosome activity during the transition of Saccharomyces cerevisiae cells into quiescence.
The class of CullinâRING E3 ligases (CRLs) selectively ubiquitinate a large portion of proteins targeted for proteolysis by the 26S proteasome. Before degradation, ubiquitin molecules are removed from their conjugated proteins by deubiquitinating enzymes, a handful of which are associated with the proteasome. The CRL activity is triggered by modification of the Cullin subunit with the ubiquitin-like protein, NEDD8 (also known as Rub1 in Saccharomyces cerevisiae). Cullin modification is then reversed by hydrolytic action of the COP9 signalosome (CSN). As the NEDD8â Rub1 catalytic cycle is not essential for the viability of S. cerevisiae, this organism is a useful model system to study the alteration of Rub1âCRL conjugation patterns. In this study, we describe two distinct mutants of Rpn11, a proteasome-associated deubiquitinating enzyme, both of which exhibit a biochemical phenotype characterized by high accumulation of Rub1-modified Cdc53âCullin1 (yCul1) upon entry into quiescence in S. cerevisiae. Further characterization revealed proteasome 19S-lid-associated deubiquitination activity that authorizes the hydrolysis of Rub1 from yCul1 by the CSN complex. Thus, our results suggest a negative feedback mechanism via proteasome capacity on upstream ubiquitinating enzymes
MPN+, a putative catalytic motif found in a subset of MPN domain proteins from eukaryotes and prokaryotes, is critical for Rpn11 function
BACKGROUND: Three macromolecular assemblages, the lid complex of the proteasome, the COP9-Signalosome (CSN) and the eIF3 complex, all consist of multiple proteins harboring MPN and PCI domains. Up to now, no specific function for any of these proteins has been defined, nor has the importance of these motifs been elucidated. In particular Rpn11, a lid subunit, serves as the paradigm for MPN-containing proteins as it is highly conserved and important for proteasome function. RESULTS: We have identified a sequence motif, termed the MPN+ motif, which is highly conserved in a subset of MPN domain proteins such as Rpn11 and Csn5/Jab1, but is not present outside of this subfamily. The MPN+ motif consists of five polar residues that resemble the active site residues of hydrolytic enzyme classes, particularly that of metalloproteases. By using site-directed mutagenesis, we show that the MPN+ residues are important for the function of Rpn11, while a highly conserved Cys residue outside of the MPN+ motif is not essential. Single amino acid substitutions in MPN+ residues all show similar phenotypes, including slow growth, sensitivity to temperature and amino acid analogs, and general proteasome-dependent proteolysis defects. CONCLUSIONS: The MPN+ motif is abundant in certain MPN-domain proteins, including newly identified proteins of eukaryotes, bacteria and archaea thought to act outside of the traditional large PCI/MPN complexes. The putative catalytic nature of the MPN+ motif makes it a good candidate for a pivotal enzymatic function, possibly a proteasome-associated deubiquitinating activity and a CSN-associated Nedd8/Rub1-removing activity
Delayed protection by ESAT-6âspecific effector CD4+ T cells after airborne M. tuberculosis infection
Mycobacterium tuberculosis infection induces complex CD4 T cell responses that include T helper type 1 (Th1) cells and regulatory T cells. Although Th1 cells control infection, they are unable to fully eliminate M. tuberculosis, suggesting that Th1-mediated immunity is restrained from its full sterilizing potential. Investigation into T cellâmediated defense is hindered by difficulties in expanding M. tuberculosisâspecific T cells. To circumvent this problem, we cloned CD4+ T cells from M. tuberculosisâinfected B6 mice and generated transgenic mice expressing a T cell receptor specific for the immunodominant antigen early secreted antigenic target 6 (ESAT-6). Adoptively transferred naive ESAT-6âspecific CD4+ T cells are activated in pulmonary lymph nodes between 7 and 10 d after aerosol infection and undergo robust expansion before trafficking to the lung. Adoptive transfer of activated ESAT-6âspecific Th1 cells into naive recipients before aerosol M. tuberculosis infection dramatically enhances resistance, resulting in 100-fold fewer bacteria in infected lungs. However, despite large numbers of Th1 cells in the lungs of mice at the time of M. tuberculosis challenge, protection was not manifested until after 7 d following infection. Our results demonstrate that pathogen-specific Th1 cells can provide protection against inhaled M. tuberculosis, but only after the first week of infection
The Effects of a 12-Week Faculty and Staff Exercise Program on Health-Related Variables in a University Setting
International Journal of Exercise Science 8(1) : 49-56, 2015. The obesity epidemic has grown in the past decade due to physical inactivity (i.e., having a sedentary job) and an increase in caloric intake. This problem combined with the reluctance of many faculty and staff members exercising in the same environment as studentâs presents a unique challenge in an academic setting. The purpose of this study was to examine the effectiveness of a 12-week exercise program focused toward the faculty and staff in improving several health-related variables such as curl-ups, push-ups, sit-and-reach, and balance. Fifty-seven faculty and staff participated in the current study. Participants engaged in a variety of exercise classes taught by certified instructors three days a week for 12-weeks. Paired samples t-tests illustrated a significant (p \u3c 0.001) decrease in body mass and significant (p \u3c 0.001) improvements in curl-ups, push-ups, sit-and-reach, and balance. This data demonstrates that a 12-week faculty and staff exercise program has the potential to improve performance in several health-related variables such as curl-ups, push-ups, sit-and-reach, and balance. The ability of this program to improve health-related variables and possibly delay or prevent the development of overweight and/or obesity, sarcopenia, and other chronic diseases is encouraging
Chaperone-driven proteasome assembly
Abstract Assembly of the 34-subunit, 2.5 MDa 26S proteasome is a carefully choreographed intricate process. It starts with formation of a seven-membered α-ring that serves as a template for assembly of the complementary ÎČ-ring-forming 'half-proteasomes'. Dimerization results in a latent 20S core particle that can serve further as a platform for 19S regulatory particle attachment and formation of the biologically active 26S proteasome for ubiquitin-dependent proteolysis. Both general and dedicated proteasome assembly chaperones regulate the efficiency and outcome of critical steps in proteasome biogenesis, and in complex association
Genome-wide mapping of the distribution of CarD, RNAP ÏA, and RNAP ÎČ on the Mycobacterium smegmatis chromosome using chromatin immunoprecipitation sequencing
CarD is an essential mycobacterial protein that binds the RNA polymerase (RNAP) and affects the transcriptional profile of Mycobacterium smegmatis and Mycobacterium tuberculosis [6]. We predicted that CarD was directly regulating RNAP function but our prior experiments had not determined at what stage of transcription CarD was functioning and at which genes CarD interacted with the RNAP. To begin to address these open questions, we performed chromatin immunoprecipitation sequencing (ChIP-seq) to survey the distribution of CarD throughout the M. smegmatis chromosome. The distribution of RNAP subunits ÎČ and ÏA were also profiled. We expected that RNAP ÎČ would be present throughout transcribed regions and RNAP ÏA would be predominantly enriched at promoters based on work in Escherichia coli [3], however this had yet to be determined in mycobacteria. The ChIP-seq analyses revealed that CarD was never present on the genome in the absence of RNAP, was primarily associated with promoter regions, and was highly correlated with the distribution of RNAP ÏA. The colocalization of ÏA and CarD led us to propose that in vivo, CarD associates with RNAP initiation complexes at most promoters and is therefore a global regulator of transcription initiation. Here we describe in detail the data from the ChIP-seq experiments associated with the study published by Srivastava and colleagues in the Proceedings of the National Academy of Science in 2013 [5] as well as discuss the findings from this dataset in relation to both CarD and mycobacterial transcription as a whole.
The ChIP-seq data have been deposited in the Gene Expression Omnibus (GEO) database, www.ncbi.nlm.nih.gov/geo (accession no. GSE48164)
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