46 research outputs found
A new intracellular serine protease inhibitor expressed in the rat pituitary gland complexes with granzyme B
AbstractWe have cloned a novel serpin (raPIT5a) from a rat pituitary cDNA library which is structurally related to members of the ovalbumin subfamily of serine protease inhibitors. This new cDNA encodes a 374-amino acid protein, designated raPIT5a. raPIT5a was expressed in specific cells in the intermediate and anterior lobes of the pituitary. Recombinant raPIT5a was not secreted suggesting raPIT5a functions to inhibit intracellular proteases. Recombinant raPIT5a formed an SDS-stable complex with human granzyme B, a serine protease which induces apoptosis by activating members of the caspase enzyme family. These data suggest raPIT5a may have a role in regulating granzyme B or related enzymes and apoptosis in the pituitary gland
Engineering the Salmonella type III secretion system to export spider silk monomers
The type III secretion system (T3SS) exports proteins from the cytoplasm, through both the inner and outer membranes, to the external environment. Here, a system is constructed to harness the T3SS encoded within Salmonella Pathogeneity Island 1 to export proteins of biotechnological interest. The system is composed of an operon containing the target protein fused to an N-terminal secretion tag and its cognate chaperone. Transcription is controlled by a genetic circuit that only turns on when the cell is actively secreting protein. The system is refined using a small human protein (DH domain) and demonstrated by exporting three silk monomers (ADF-1, -2, and -3), representative of different types of spider silk. Synthetic genes encoding silk monomers were designed to enhance genetic stability and codon usage, constructed by automated DNA synthesis, and cloned into the secretion control system. Secretion rates up to 1.8 mg lâ1 hâ1 are demonstrated with up to 14% of expressed protein secreted. This work introduces new parts to control protein secretion in Gram-negative bacteria, which will be broadly applicable to problems in biotechnology
Increased Incidence of Vestibular Disorders in Patients With SARS-CoV-2
OBJECTIVE: Determine the incidence of vestibular disorders in patients with SARS-CoV-2 compared to the control population.
STUDY DESIGN: Retrospective.
SETTING: Clinical data in the National COVID Cohort Collaborative database (N3C).
METHODS: Deidentified patient data from the National COVID Cohort Collaborative database (N3C) were queried based on variant peak prevalence (untyped, alpha, delta, omicron 21K, and omicron 23A) from covariants.org to retrospectively analyze the incidence of vestibular disorders in patients with SARS-CoV-2 compared to control population, consisting of patients without documented evidence of COVID infection during the same period.
RESULTS: Patients testing positive for COVID-19 were significantly more likely to have a vestibular disorder compared to the control population. Compared to control patients, the odds ratio of vestibular disorders was significantly elevated in patients with untyped (odds ratio [OR], 2.39; confidence intervals [CI], 2.29-2.50;
CONCLUSIONS: The incidence of vestibular disorders differed between COVID-19 variants and was significantly elevated in COVID-19-positive patients compared to the control population. These findings have implications for patient counseling and further research is needed to discern the long-term effects of these findings
Identification and rejection of pile-up jets at high pseudorapidity with the ATLAS detector
The rejection of forward jets originating from
additional protonâproton interactions (pile-up) is crucial for
a variety of physics analyses at the LHC, including Standard
Model measurements and searches for physics beyond
the Standard Model. The identification of such jets is challenging
due to the lack of track and vertex information in
the pseudorapidity range |η| > 2.5. This paper presents a
novel strategy for forward pile-up jet tagging that exploits
jet shapes and topological jet correlations in pile-up interactions.
Measurements of the per-jet tagging efficiency are
presented using a data set of 3.2 fbâ1 of protonâproton collisions
at a centre-of-mass energy of 13 TeV collected with the
ATLAS detector. The fraction of pile-up jets rejected in the
range 2.5 < |η| < 4.5 is estimated in simulated events with
an average of 22 interactions per bunch-crossing. It increases
with jet transverse momentum and, for jets with transverse
momentum between 20 and 50 GeV, it ranges between 49%
and 67% with an efficiency of 85% for selecting hard-scatter
jets. A case study is performed in Higgs boson production
via the vector-boson fusion process, showing that these techniques
mitigate the background growth due to additional
protonâproton interactions, thus enhancing the reach for such
signatures
Physical Activity Patterns Using Accelerometry in the National Weight Control Registry
The National Weight Control Registry (NWCR) was established in 1993 to examine characteristics of successful weight-loss maintainers. This group consistently self-reports high levels of physical activity. The aims of this study were to obtain objective assessments of physical activity in NWCR subjects and compare this to physical activity in both normal-weight and overweight controls. Individuals from the NWCR (n = 26) were compared to a neverâobese normal-weight control group matched to the NWCR groupâs current BMI (n = 30), and an overweight control group matched to the NWCR groupâs self-reported pre-weight-loss BMI (n = 34). Objective assessment of physical activity was obtained for a 1-week period using a triaxial accelerometer. Bouts of moderate-to-vigorous physical activity (MVPA) â„10 min in duration, as well as nonbout MVPA (bouts of MVPA 1â9 min in duration) were summed and characterized. NWCR subjects spent significantly (P = 0.004) more time per day in sustained bouts of MVPA than overweight controls (41.5 ± 35.1 min/day vs. 19.2 ± 18.6 min/day) and marginally (P = 0.080) more than normal controls (25.8 ± 23.4). There were no significant differences between the three groups in the amount of nonbout MVPA. These results provide further evidence that physical activity is important for long-term maintenance of weight loss and suggest that sustained volitional activity (i.e., â„10 min in duration) may play an important role. Interventions targeting increases in structured exercise may be needed to improve long-term weight-loss maintenance
Milestones in electron crystallography
Electron crystallography determines the structure of membrane embedded proteins in the two-dimensionally crystallized state by cryo-transmission electron microscopy imaging and computer structure reconstruction. Milestones on the path to the structure are high-level expression, purification of functional protein, reconstitution into two-dimensional lipid membrane crystals, high-resolution imaging, and structure determination by computer image processing. Here we review the current state of these methods. We also created an Internet information exchange platform for electron crystallography, where guidelines for imaging and data processing method are maintained. The server (http://2dx.org) provides the electron crystallography community with a central information exchange platform, which is structured in blog and Wiki form, allowing visitors to add comments or discussions. It currently offers a detailed step-by-step introduction to image processing with the MRC software program. The server is also a repository for the 2dx software package, a user-friendly image processing system for 2D membrane protein crystals
Milestones in electron crystallography
Electron crystallography determines the structure of membrane embedded proteins in the two-dimensionally crystallized state by cryo-transmission electron microscopy imaging and computer structure reconstruction. Milestones on the path to the structure are high-level expression, purification of functional protein, reconstitution into two-dimensional lipid membrane crystals, high-resolution imaging, and structure determination by computer image processing. Here we review the current state of these methods. We also created an Internet information exchange platform for electron crystallography, where guidelines for imaging and data processing method are maintained. The server (http://2dx.org) provides the electron crystallography community with a central information exchange platform, which is structured in blog and Wiki form, allowing visitors to add comments or discussions. It currently offers a detailed step-by-step introduction to image processing with the MRC software program. The server is also a repository for the 2dx software package, a user-friendly image processing system for 2D membrane protein crystals