Publications by authors named "Katherine Graham"

Cyclization is a widely used approach to exert conformational restraint on linear peptide sequences. Herein, urea bridge chemistry was deployed to achieve side chain-to-side chain peptide cyclization on the CSP1-E1A peptide scaffold. To determine the effects of ring size and bridge position on the overall peptide conformation and find the ideal area within the CSP sequence for cyclization, we performed biological evaluation as well as secondary structure analysis on all the cyclic analogs.

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Leatherback turtles () are endangered by anthropogenic threats. Characterizing the physiologic response of leatherback turtles under various stressors may inform conservation strategies. In this study, a commercially available enzyme immunoassay for aldosterone was validated for leatherback turtle plasma, and it was used with previously validated assays for corticosterone and free thyroxine (fT4) to evaluate the physiologic status of leatherback turtles that were entangled in fishing gear, stranded on shore, nesting or intentionally captured at sea during ecologic studies.

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Advancements within fecal source tracking (FST) studies are complicated by a lack of knowledge regarding the genetic content and distribution of fecally shed microbial populations. To address this gap, we performed a systematic literature review and curated a large collection of genomes (n = 26,018) representing fecally shed prokaryotic species across broad and narrow source categories commonly implicated in FST studies of recreational waters (i.e.

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The sequencing of intact proteins within a mass spectrometer has many benefits but is frequently limited by the fact that tandem mass spectrometry (MS/MS) techniques often generate poor sequence coverages when applied to protein ions. To overcome this limitation, exotic MS/MS techniques that rely on lasers and radical chemistry have been developed. These techniques generate high sequence coverages, but they require specialized instrumentation, create products through multiple dissociation mechanisms, and often require long acquisition times.

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As global temperatures rise with climate change, the negative effects of heat on drinking water distribution systems (DWDS) are of increasing concern. High DWDS temperatures are associated with degradation of water quality through physical, chemical and microbial mechanisms. Perhaps the most pressing concern is proliferation of thermotolerant opportunistic pathogens (OPs) like Legionella pneumophila and Naegleria Fowleri.

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The instability of viral targets including SARS-CoV-2 in sewage is an important challenge in wastewater monitoring projects. The unrecognized interruptions in the 'cold-chain' transport from the sample collection to RNA quantification in the laboratory may undermine the accurate quantification of the virus. In this study, bovine serum albumin (BSA)-modified porous superabsorbent polymer (PSAP) beads were applied to absorb raw sewage samples as a simple method for viral RNA preservation.

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Introduction: Complex PTSD (CPTSD) is a relatively new condition in ICD-11. This pilot randomised controlled trial aimed to compare a four-module intervention developed to target all symptoms of ICD-11 CPTSD, namely Enhanced Skills in Affective and Interpersonal Regulation (ESTAIR) with treatment as usual (TAU). The purpose of the study was to assess feasibility, safety, acceptability, and preliminary outcomes at the end of treatment and 3-month follow-up.

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Moore swabs have re-emerged as a versatile tool in the field of wastewater-based epidemiology during the COVID-19 pandemic and offer unique advantages for monitoring pathogens in sewer systems, especially at the neighborhood-level. However, whether Moore swabs provide comparable results to more commonly used composite samples remains to be rigorously tested including the optimal duration of Moore swab deployment. This study provides new insights into these issues by comparing the results from Moore swab samples to those of paired composite samples collected from the same sewer lines continuously over six to seventy-two hours post-deployment, during low COVID-19 prevalence periods.

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Microbial source tracking (MST) identifies sources of fecal contamination in the environment using host-associated fecal markers. While there are numerous bacterial MST markers that can be used herein, there are few such viral markers. Here, we designed and tested novel viral MST markers based on tomato brown rugose fruit virus (ToBRFV) genomes.

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Mass spectrometry (MS)-based proteomics workflows of intact protein ions have increasingly been utilized to study biological systems. These workflows, however, frequently result in convoluted and difficult to analyze mass spectra. Ion mobility spectrometry (IMS) is a promising tool to overcome these limitations by separating ions by their mass- and size-to-charge ratios.

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Unlabelled: Microbial source tracking (MST) identifies sources of fecal contamination in the environment using fecal host-associated markers. While there are numerous bacterial MST markers, there are few viral markers. Here we design and test novel viral MST markers based on tomato brown rugose fruit virus (ToBRFV) genomes.

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Wastewater-based epidemiology during the COVID-19 pandemic has proven useful for public health decision-making but is often hampered by sampling methodology constraints, particularly at the building- or neighborhood-level. Time-weighted composite samples are commonly used; however, autosamplers are expensive and can be affected by intermittent flows in sub-sewershed contexts. In this study, we compared time-weighted composite, grab, and passive sampling via Moore swabs, at four locations across a college campus to understand the utility of passive sampling.

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Limited information is available on the decay rate of endogenous SARS-CoV-2 and pepper mild mottle virus (PMMoV) RNA in wastewater and primary settled solids, potentially limiting an understanding of how transit or holding times within wastewater infrastructure might impact RNA measurements and their relationship to community COVID-19 infections. In this study, primary settled solids samples were collected from two wastewater treatment plants in the San Francisco Bay Area. Samples were thoroughly mixed, aliquoted into subsamples, and stored at 4, 22, and 37 °C for 10 days.

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Estimating total infection levels, including unreported and asymptomatic infections, is important for understanding community disease transmission. Wastewater can provide a pooled community sample to estimate total infections that is independent of case reporting biases toward individuals with moderate to severe symptoms and by test-seeking behavior and access. We derive three mechanistic models for estimating community infection levels from wastewater measurements based on a description of the processes that generate SARS-CoV-2 RNA signals in wastewater and accounting for the fecal strength of wastewater through endogenous microbial markers, daily flow, and per-capita wastewater generation estimates.

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Article Synopsis
  • Green stormwater infrastructure systems, like biofilters, have environmental benefits but their effectiveness at removing human pathogens and antibiotic resistance genes (ARGs) is not well understood.
  • A study conducted on a biofilter in Southern California found it significantly removed about 82% of tested microbial markers and ARGs, showing varying effectiveness among them.
  • The results suggest that while biofilters can reduce contaminants during stormwater runoff, there is high variability in their ability to do so and they may not reliably serve as indicators for pathogen removal.
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Native mass spectrometry and collision-induced unfolding (CIU) workflows continue to grow in utilization due to their ability to rapidly characterize protein conformation and stability. To perform these experiments, the instrument must be capable of collisionally activating ions prior to ion mobility spectrometry (IMS) analyses. Trapped ion mobility spectrometry (TIMS) is an ion mobility implementation that has been increasingly adopted due to its inherently high resolution and reduced instrumental footprint.

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Urban runoff is one of the greatest sources of microbial pollution to surface waters. Biofilters can limit the impact of stormwater runoff on surface water quality by diverting runoff from receiving waters. However, our understanding of how biofilter design choices, including the addition of vegetation and geomedia, may impact the removal of pathogens is lacking.

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Ion mobility separations (IMS) have increasingly been coupled with mass spectrometry to increase peak capacity and deconvolute complex mass spectra in proteomics workflows. IMS separations can be integrated prior to or following the collisional activation step. Post-activation IMS separations have demonstrated many advantages, yet few instrument platforms are capable of this feat.

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Birds in agricultural environments have exhibited steep global population declines in recent decades, and effective conservation strategies targeting their populations are urgently needed. In grasslands used for hay production, breeding birds' nest success improves substantially if hay harvests are delayed until after mid-July. However, few studies have investigated private hay producers' willingness to alter their harvesting practices, which is a critical factor for bird conservation where most land is privately owned, such as in the North American Great Plains.

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Published and unpublished reports show that SARS-CoV-2 RNA in publicly owned treatment work (POTW) wastewater influent and solids is associated with new COVID-19 cases or incidence in associated sewersheds, but methods for comparing data collected from diverse POTWs to infer information about the relative incidence of laboratory-confirmed COVID-19 cases, and scaling to allow such comparisons, have not been previously established. Here, we show that SARS-CoV-2 N1 and N2 concentrations in solids normalized by concentrations of PMMoV RNA in solids can be used to compare incidence of laboratory confirmed new COVID-19 cases across POTWs. Using data collected at seven POTWs along the United States West Coast, Midwest, and East Coast serving ∼3% of the U.

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As studies quantifying steroid hormones in marine mammal blubber progress, methodological refinements may improve the utility and consistency of blubber hormone measurements. This study advances blubber extraction methodologies by testing a simplified extraction protocol that reduces time and complexity compared to a protocol widely used in cetacean blubber studies. Using blubber samples archived from remote biopsy ( = 21 live whales) and necropsy collection ( = 7 dead whales) of North Atlantic right whales (NARW; ) of known life history states, we performed analytical and biological validations to assess the feasibility of measuring reproductive (testosterone, progesterone) and glucocorticoid (cortisol) hormones in blubber via enzyme immunoassay following the simplified extraction.

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Wastewater-based epidemiology may be useful for informing public health response to viral diseases like COVID-19 caused by SARS-CoV-2. We quantified SARS-CoV-2 RNA in wastewater influent and primary settled solids in two wastewater treatment plants to inform the preanalytical and analytical approaches and to assess whether influent or solids harbored more viral targets. The primary settled solids samples resulted in higher SARS-CoV-2 detection frequencies than the corresponding influent samples.

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The mechanisms by which bacteria sense and respond to surface attachment have long been a mystery. Our understanding of the structure and dynamics of bacterial appendages, notably type IV pili (T4P), provided new insights into the potential ways that bacteria sense surfaces. T4P are ubiquitous, retractable hair-like adhesins that until recently were difficult to image in the absence of fixation due to their nanoscale size.

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