Publications by authors named "Perdue S"

Background: Necrotizing pneumonia caused by methicillin-resistant Staphylococcus aureus can lead to the formation of pneumatoceles in the lungs. Standard treatment guidelines are not available due to the rarity of pneumatoceles in neonates.

Clinical Findings: Baby H.

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Experimental data about gene functions curated from the primary literature have enormous value for research scientists in understanding biology. Using the Gene Ontology (GO), manual curation by experts has provided an important resource for studying gene function, especially within model organisms. Unprecedented expansion of the scientific literature and validation of the predicted proteins have increased both data value and the challenges of keeping pace.

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Ehrlichioses and anaplasmosis have undergone dramatic increases in incidence, and the geographic ranges of their occurrence and vectors have also expanded. There is marked underreporting of these diseases owing to deficient physician awareness and knowledge of the illnesses as well as limited access to appropriate diagnostic tests. Human monocytic ehrlichiosis and anaplasmosis are life threatening diseases with estimated case fatality rates of 2.

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A 24-year-old female presented with sepsis and cardiogenic shock 4 days after vaginal delivery. Veno-arterial extracorporeal membrane oxygenation (VA ECMO) therapy was used for cardiovascular support as a bridge for recovery. The use of VA ECMO in patients with cardiogenic shock secondary to sepsis is reviewed.

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Spatial organization via encapsulation of enzymes within recombinant nanocompartments may increase efficiency in multienzyme cascades. Previously, we reported the encapsulation of single cargo proteins within nanocompartments in the heterologous host Escherichia coli. This was achieved by coexpression of the Salmonella enterica LT2 ethanolamine utilization bacterial microcompartment shell proteins EutS or EutSMNLK, with a signal sequence EutC1-19 cargo protein fusion.

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Compartmentalization of designed metabolic pathways within protein based nanocompartments has the potential to increase reaction efficiency in multi-step biosynthetic reactions. We previously demonstrated proof-of-concept of this aim by targeting a functional enzyme to single cellular protein nanocompartments, which were formed upon recombinant expression of the Salmonella enterica LT2 ethanolamine utilization bacterial microcompartment shell proteins EutS or EutSMNLK in Escherichia coli. To optimize this system, increasing overall encapsulated enzyme reaction efficiency, factor(s) required for the production of more than one nanocompartment per cell must be identified.

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The RNA chaperone Hfq fulfills important roles in small regulatory RNA (sRNA) function in many bacteria. Loss of Hfq in the dissimilatory metal reducing bacterium Shewanella oneidensis strain MR-1 results in slow exponential phase growth and a reduced terminal cell density at stationary phase. We have found that the exponential phase growth defect of the hfq mutant in LB is the result of reduced heme levels.

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We demonstrate a conductance switch controlled by the spin-vibronic density of an odd electron on a single molecule. The junction current is modulated by the spin-flip bistability of the electron. Functional images are provided as wiring diagrams for control of the switch's frequency, amplitude, polarity, and duty-cycle.

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Electroluminescence (EL) in scanning tunneling microscopy (STM), which enables spectroscopy with submolecular spatial resolution, is shown to be due to radiative ionization with vibronic shape resonances that carry Fano line profiles. Since Fano progressions retain phase information, the spectra can be transformed to the time domain to reconstruct the vibronic motion. In effect, measurements within a molecule are accessible with joint space-time resolution at the Å-fs limit.

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Fabrication of sharp and smooth Ag tips is crucial in optical scanning probe microscope experiments. To ensure reproducible tip profiles, the polishing process is fully automated using a closed-loop laminar flow system to deliver the electrolytic solution to moving electrodes mounted on a motorized translational stage. The repetitive translational motion is controlled precisely on the μm scale with a stepper motor and screw-thread mechanism.

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The Jahn-Teller (JT) active unpaired electron of single metalloporphyrin radical anions is imaged through scanning tunneling microscopy. It is demonstrated that the electron is delocalized over the porphyrin macrocycle and its topographic image is determined by vibronic motion: the orbital of the electron adiabatically follows the zero-point pseudorotation of skeletal deformations. Transformation of the polar graphs of the observed images allows visualization of the adiabatic vibrational density to which the electron is coupled.

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RNA polymerase of both bacteria and eukaryotes can stall or pause within tens of base pairs of its initiation site at the promoter, a state that may reflect important regulatory events in early transcription. In the bacterial model system, the σ(70) initiation factor stabilizes such pauses by binding a downstream repeat of a promoter segment, especially the '-10' promoter element. We first show here that the '-35' promoter element also can stabilize promoter-proximal pausing, through interaction with σ(70) region 4.

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After promoter escape in Escherichia coli, the initiating σ(70) factor is retained by core RNA polymerase (RNAP) for at least tens of nucleotides. While it is bound, σ(70) can engage a repeat of a promoter DNA element located downstream of the promoter and thereby induce a transcription pause. The σ(70)-dependent promoter-proximal pause that occurs at all lambdoid phage late gene promoters is essential to regulation of the late gene operons.

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We introduce the cross-polarized double-beat method for localized excitation of the junction plasmon of a scanning tunneling microscope with femtosecond laser pulses. We use two pulse trains derived from a Ti:sapphire laser operating at a repetition frequency of f(s)=76 MHz, with a relative shift between their carrier frequencies ω(a)/2π=f(s)+f(b) controlled with an acousto-optic modulator. The trains are cross-polarized and collinearly focused on the junction, ensuring constant radiation flux.

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The objective of this study was to determine the prevalence and concordance of Mycoplasma genitalium (MG) among Mexican American and African American women and their male sexual partners. Secondary objectives were to determine symptoms of MG infection and persistence of MG after antibiotic therapy. Heterosexual couples were tested for MG and interviewed separately regarding symptoms and behavioural/epidemiologic variables at baseline, six and 12 months.

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Objectives: We compared the male sexual partners of teen girls of age 15 to 19 years, currently infected with a sexually transmitted infection (STI) versus the male partners of adult women of age 20 to 41 years, with an STI to determine risk factors in these high-risk sexual dyads related to the male partner.

Study Design: Interview of 514 men who were partnered with 152 teen girls and 362 adult women, enrolled in Project Sexual Awareness for Everyone, a randomized controlled trial of behavioral intervention to reduce recurrent STIs.

Results: Compared to the male partners of adult women, male partners of teen girls were significantly more likely (P < 0.

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Background: The objective was to determine the acceptability and use patterns of potential microbicides among African American (AA), acculturated Hispanic (AH), and less acculturated Hispanic (LAH) women. We measured baseline sexual risk-taking and the likelihood of behavioral change, given effective microbicides.

Methods: Interview of 506 Mexican-American and AA women, all of whom have a sexually transmitted infection enrolled in Project Sexual Awareness for Everyone.

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Chlamydia trachomatis genome is predicted to encode a type III secretion system consisting of more than 40 open reading frames (ORFs). To test whether these ORFs are expressed and immunogenic during chlamydial infection in humans, we expressed 55 chlamydial ORFs covering all putative type III secretion components plus control molecules as fusion proteins and measured the reactivity of these fusion proteins with antibodies from patients infected with C. trachomatis in the urogenital tract (24 antisera) or in the ocular tissue (8 antisera).

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The proper regulation of factors involved in mitosis is crucial to ensure normal cell division. Levels and activities of proteins are regulated in many ways, one of which is ubiquitin-mediated protein degradation. E3 ubiquitin ligases are involved in targeting specific substrates for degradation by facilitating their ubiquitination.

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Background: A randomized controlled trial of SAFE, a cognitive/behavioral intervention, revealed that it significantly reduces reinfection and behavioral risks among participants compared with controls. However, studies suggest that depression may moderate intervention efficacy among affected persons because of impaired information processing, failure to recognize risk, or inability to change behavior.

Goal: We evaluated SAFE efficacy among depressed and nondepressed Mexican- and African American women after comparing initial risk factors by depression status.

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Objective: To compare the efficacy of a randomized controlled trial of the Sexual Awareness For Everyone (SAFE) behavioral intervention on teenagers (aged 14 to 18 years) compared with adult rates of reinfection with Neiserria gonorrhea or Chlamydia trachomatis cervicitis, and to identify behaviors associated with recurrent infection.

Methods: Mexican-American and African-American females with a nonviral sexually transmitted disease (STD) were enrolled in SAFE or assigned to the control group. All participants were interviewed and examined at baseline, 6, and 12 months.

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The object of this study was to determine the factors associated with partner notification (PN) of sexually transmitted infection (STI) exposure among pregnant, low income, Mexican-American (MA) and African-American (AA) women and their male sexual partners. We used a cross-sectional analysis of 166 pregnant women with an STI, enrolled in a randomized controlled trial of behavioural intervention to prevent recurrent STIs. The primary outcome, PN, is notification of, or intent to notify male sexual partner(s) of STI exposure.

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Objectives: To determine factors associated with partner notification (PN) of sexually transmitted infection (STI) exposure among low-income Mexican American and African American women and their male sexual partners.

Goal: To identify women most likely to notify their partners about an STI exposure.

Study Design: Cross-sectional analysis of 775 women with a nonviral STI.

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Problem: Mycoplasma genitalium has been associated with male urethritis. We sought to relate M. genitalium to genitourinary signs and symptoms in women.

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