Catalogue Search | MBRL
Search Results Heading
Explore the vast range of titles available.
MBRLSearchResults
-
DisciplineDiscipline
-
Is Peer ReviewedIs Peer Reviewed
-
Item TypeItem Type
-
SubjectSubject
-
YearFrom:-To:
-
More FiltersMore FiltersSourceLanguage
Done
Filters
Reset
35
result(s) for
"Timm, Karen"
Sort by:
Multicenter Evaluation of the Bruker MALDI Biotyper CA System for the Identification of Clinical Aerobic Gram-Negative Bacterial Isolates
by
Granato, Paul A.
,
Marlowe, Elizabeth
,
Procop, Gary W.
in
Bacteria
,
Bacterial infections
,
Bacterial Typing Techniques - instrumentation
2015
The prompt and accurate identification of bacterial pathogens is fundamental to patient health and outcome. Recent advances in matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) have revolutionized bacterial identification in the clinical laboratory, but uniform incorporation of this technology in the U.S. market has been delayed by a lack of FDA-cleared systems. In this study, we conducted a multicenter evaluation of the MALDI Biotyper CA (MBT-CA) System (Bruker Daltonics Inc, Billerica, MA) for the identification of aerobic gram-negative bacteria as part of a 510(k) submission to the FDA. A total of 2,263 aerobic gram negative bacterial isolates were tested representing 23 genera and 61 species. Isolates were collected from various clinical sources and results obtained from the MBT-CA System were compared to DNA sequencing and/or biochemical testing. Isolates that failed to report as a \"high confidence species ID\" [log(score) ≥2.00] were re-tested using an extraction method. The MBT-CA System identified 96.8% and 3.1% of isolates with either a \"high confidence\" or a \"low confidence\" [log(score) value between 1.70 and <2.00] species ID, respectively. Two isolates did not produce acceptable confidence scores after extraction. The MBT-CA System correctly identified 99.8% (2,258/2,263) to genus and 98.2% (2,222/2,263) to species level. These data demonstrate that the MBT-CA System provides accurate results for the identification of aerobic gram-negative bacteria.
Journal Article
Diagnostic performance of two molecular assays for the detection of vaginitis in symptomatic women
2020
The three main causes of vaginitis are bacterial vaginosis (BV), vulvovaginal candidiasis (VVC), and trichomoniasis (TV). Two multiplex assays are commercially available for detection of DNA from organisms associated with vaginitis: BD Affirm™ VPIII Microbial Identification Test (Affirm) and BD MAX™ Vaginal Panel (MAX VP). Here, the performance of MAX VP was compared to that of Affirm, which was considered the standard of care. Four vaginal swabs were collected from each subject with the following: BD Affirm™ VPIII Ambient Temperature Transport System (ATTS), BD MAX™ UVE Specimen Collection Kit, Hologic Aptima® Vaginal Swab Specimen Collection Kit, and BD ESwab™ collection and transport system (ESwab). Candida culture, Gram stain followed by Nugent scoring, and the Hologic Aptima® Trichomonas vaginalis assay were used for discordant analysis. Results were considered true positive if there were at least two tests positive for any vaginitis target. A total of 200 symptomatic women were evaluated in the study. The sensitivity and specificity of MAX VP for BV was 96.2% and 96.1%, respectively, compared to 96.2% and 81.6% for Affirm. The sensitivity and specificity of MAX VP for Candida spp. was 98.4% and 95.4%, respectively, compared to 69.4% and 100% for Affirm. MAX VP and Affirm showed 100% concordance for detection of TV. These results demonstrate improved accuracy of MAX VP compared to Affirm for the detection of BV and Candida spp. and no difference for detection of TV between the two tests.
Journal Article
Multicenter Evaluation of the Bruker MALDI Biotyper CA System for the Identification of Clinically Important Bacteria and Yeasts
by
Granato, Paul A.
,
Procop, Gary W.
,
Lillie, Jennifer L.
in
Bacteria
,
Bacteria - isolation & purification
,
Bacterial Typing Techniques
2017
Objectives: A report on the multicenter evaluation of the Bruker MALDI Biotyper CA System (MBT-CA; Bruker Daltonics, Billerica, MA) for the identification of clinically important bacteria and yeasts.
Methods: In total, 4,399 isolates of medically important bacteria and yeasts were assessed in the MBT-CA. These included 2,262 aerobic gram-positive (AGP) bacteria, 792 aerobic gram-negative (AGN) bacteria 530 anaerobic (AnA) bacteria, and 815 yeasts (YSTs). Three processing methods were assesed.
Results: Overall, 98.4% (4,329/4,399) of all bacterial and yeast isolates were correctly identified to the genus and species/species complex level, and 95.7% of isolates were identified with a high degree of confidence. The percentage correctly identified and the percentage identified correctly with a high level of confidence, respectively, were as follows: AGP bacteria (98.6%/96.5%), AGN bacteria (98.5%/96.8%), AnA bacteria (98.5%/97.4%), and YSTs (97.8%/87.6%). The extended direct transfer method was only minimally superior to the direct transfer method for bacteria (89.9% vs 86.8%, respectively) but significantly superior for yeast isolates (74.0% vs 48.9%, respectively).
Conclusions: The Bruker MALDI Biotyper CA System accurately identifies most clinically important bacteria and yeasts and has optional processing methods to improve isolate characterization.
Journal Article
Vaccination with Acinetobacter baumannii adhesin Abp2D provides protection against catheter-associated urinary tract infection
2025
Catheter-associated urinary tract infections (CAUTIs) contribute greatly to the burden of healthcare-associated infections.
Acinetobacter baumannii
is a Gram-negative bacterium with high levels of antibiotic resistance that is of increasing concern as a CAUTI pathogen.
A. baumannii
expresses fibrinogen-binding adhesins (Abp1D and Abp2D) that mediate biofilm formation on catheters, which become coated with fibrinogen upon insertion. Here we develop a protein subunit vaccine against the Abp1D and Abp2D receptor binding domains (RBD) and show that vaccination significantly reduces bacterial titers in a female mouse model of CAUTI. We further demonstrate that immunity to Abp2D
RBD
alone is sufficient for protection. Mechanistically, we define the B cell response to Abp2D
RBD
vaccination, demonstrate that passive immunization with Abp2D
RBD
-immune serum transfers immunity to naïve mice, and show that Abp2D
RBD
-immune serum inhibits bacterial binding to fibrinogen-coated catheters. This work represents an antibiotic-sparing strategy for the prevention of
A. baumannii
CAUTI which has an important role in the global fight against antimicrobial resistance.
Acinetobacter baumannii
is a multi-drug-resistant pathogen of urgent international concern. Here, the authors develop a protein subunit vaccine which prevents
A. baumannii
catheter-associated urinary tract infections in mice by inhibiting Abp2D, a key adhesive virulence factor.
Journal Article
Effects of silver nanoparticles on the physiology, stress, and mineral uptake of banana cultivars in vitro and greenhouse
2025
This study explores the effects of silver nanoparticles (AgNPs) from the formulation Argovit™ on physiological stress responses and mineral uptake in banana cultivars, both
and under greenhouse conditions. These specific AgNPs have been previously studied for their antifungal activity against
, highlighting their potential as a disease control agent in banana cultivation. Evaluating their phytotoxicity is crucial to determine safe application levels, particularly at the concentrations previously shown to be effective.
The primary objective is to expose the phytotoxic effects, nutrient uptake, and translocation mechanisms of AgNPs based on their application method, either foliar or drench.
experiments on the Cavendish banana var. Williams, with shoots cultured in media supplemented with AgNPs at concentrations of 0, 25, 50, 100, and 1000 mg L
, showed significant reductions in shoot formation, length, chlorophyll content, and leaf number as AgNP concentrations increased. Rooting experiments revealed similar trends with high AgNP concentrations resulting in a decreasing root number and size. Greenhouse experiments on Gros Michel bananas, evaluating AgNP uptake through foliar and drench applications at 0, 25, 50, and 100 mg L
, monitored over a month, showed no statistically significant differences in growth parameters between treated plants and controls. However, tissue analysis revealed higher leaf Ag concentrations than roots and stems. The study also analyzed antioxidant gene expression via qPCR, targeting genes such as
(superoxide dismutase),
(catalase)
(ascorbate peroxidase), and
(glutathione peroxidase), showing altered profiles in response to AgNP exposure and indicating induced oxidative stress. This research underscores the complex interactions between AgNPs and banana plants, emphasizing the need for further study to optimize safe and effective AgNP application in agriculture, balancing crop protection and environmental safety.
Journal Article
A proposed framework for the development and qualitative evaluation of West Nile virus models and their application to local public health decision-making
by
Kilpatrick, A. Marm
,
Fredregill, Chris L.
,
Wimberly, Michael C.
in
60 APPLIED LIFE SCIENCES
,
Adulticides
,
Aquatic insects
2021
West Nile virus (WNV) is a globally distributed mosquito-borne virus of great public health concern. The number of WNV human cases and mosquito infection patterns vary in space and time. Many statistical models have been developed to understand and predict WNV geographic and temporal dynamics. However, these modeling efforts have been disjointed with little model comparison and inconsistent validation. In this paper, we describe a framework to unify and standardize WNV modeling efforts nationwide. WNV risk, detection, or warning models for this review were solicited from active research groups working in different regions of the United States. A total of 13 models were selected and described. The spatial and temporal scales of each model were compared to guide the timing and the locations for mosquito and virus surveillance, to support mosquito vector control decisions, and to assist in conducting public health outreach campaigns at multiple scales of decision-making. Our overarching goal is to bridge the existing gap between model development, which is usually conducted as an academic exercise, and practical model applications, which occur at state, tribal, local, or territorial public health and mosquito control agency levels. The proposed model assessment and comparison framework helps clarify the value of individual models for decision-making and identifies the appropriate temporal and spatial scope of each model. This qualitative evaluation clearly identifies gaps in linking models to applied decisions and sets the stage for a quantitative comparison of models. Specifically, whereas many coarse-grained models (county resolution or greater) have been developed, the greatest need is for fine-grained, short-term planning models (m–km, days–weeks) that remain scarce. We further recommend quantifying the value of information for each decision to identify decisions that would benefit most from model input.
Journal Article
Glutamate dynamics in the dorsolateral striatum of rats with goal-directed and habitual cocaine-seeking behavior
by
Wilcox, Karen S.
,
Giangrasso, Danielle M.
,
Veros, Kaliana M.
in
astrocytes
,
cocaine
,
devaluation
2023
The shift from drug abuse to addiction is considered to arise from the transition between goal-directed and habitual control over drug behavior. Habitual responding for appetitive and skill-based behaviors is mediated by potentiated glutamate signaling in the dorsolateral striatum (DLS), but the state of the DLS glutamate system in the context of habitual drug-behavior remains undefined. Evidence from the nucleus accumbens of cocaine-experienced rats suggests that decreased transporter-mediated glutamate clearance and enhanced synaptic glutamate release contribute to the potentiated glutamate signaling that underlies the enduring vulnerability to relapse. Preliminary evidence from the dorsal striatum of cocaine-experienced rats suggests that this region exhibits similar alterations to glutamate clearance and release, but it is not known whether these glutamate dynamics are associated with goal-directed or habitual control over cocaine-seeking behavior. Therefore, we trained rats to self-administer cocaine in a chained cocaine-seeking and -taking paradigm, which yielded goal-directed, intermediate, and habitual cocaine-seeking rats. We then assessed glutamate clearance and release dynamics in the DLS of these rats using two different methods: synaptic transporter current (STC) recordings of patch-clamped astrocytes and the intensity-based glutamate sensing fluorescent reporter (iGluSnFr). While we observed a decreased rate of glutamate clearance in STCs evoked with single-pulse stimulation in cocaine-experienced rats, we did not observe any cocaine-induced differences in glutamate clearance rates from STCs evoked with high frequency stimulation (HFS) or iGluSnFr responses evoked with either double-pulse stimulation or HFS. Furthermore, GLT-1 protein expression in the DLS was unchanged in cocaine-experienced rats, regardless of their mode of control over cocaine-seeking behavior. Lastly, there were no differences in metrics of glutamate release between cocaine-experienced rats and yoked-saline controls in either assay. Together, these results suggest that glutamate clearance and release dynamics in the DLS are largely unaltered by a history of cocaine self-administration on this established cocaine seeking-taking paradigm, regardless of whether the control over the cocaine seeking behavior was habitual or goal directed.
Journal Article
Early integration of palliative care in hospitals: A systematic review on methods, barriers, and outcome
by
Nielsen, Marianne Espenhain
,
Dalgaard, Karen Marie
,
Bergenholtz, Heidi
in
Cancer
,
Chronic obstructive pulmonary disease
,
Clinical practice guidelines
2014
According to the World Health Organization (WHO), palliative care (PC) should be available to everyone suffering from life-threatening diseases and should be started early on in the illness trajectory. However, PC is often initiated much later and is restricted to cancer patients. There is a need for more knowledge about how early PC can be implemented in clinical practice. The purpose of our study was to document the best evidence on methods for early identification (EI) of palliative trajectories in cancer, chronic heart failure (CHF), and chronic obstructive pulmonary disease (COPD) populations, and to identify preconditions for early integration of general PC in hospitals and outcomes for patients and relatives.
A comprehensive systematic review of methods, preconditions, and outcomes was conducted via an electronic literature search of publications between 2002 and September 2012. A final sample of 44 papers was reviewed in detail.
Our study identified disease-specific and general methods for EI of patients who might benefit from PC. Prognostication of end-stage disease based on (holistic) clinical judgment, prognostic factors, and/or care needs are the most frequently recommended methods. A number of interacting disease-, staff-, user-, and organization-specific barriers need to be overcome in order to implement early integration of PC in clinical practice. Early integration of PC may lead to better symptom management, prolonged survival, and better quality of life.
No methods can be recommended for routine clinical practice without further validation. There is an urgent need to develop and evaluate methods based on the holistic assessment of symptoms or needs. The barriers to early integration of PC are most extensive with regard to CHF and COPD. Professional training and education are recommended to facilitate early implementation of PC. The evidence about outcome is sparse and mostly relates to cancer populations receiving specialized PC.
Journal Article
The Growth and Disciplinary Convergence of Environmental Communication: A Bibliometric Analysis of the Field (1970–2019)
by
Timm, Kristin M. F.
,
Olds, James L.
,
Akerlof, Karen L.
in
bibliometric analysis
,
convergence
,
environmental communication
2022
Recent reviews describe academic scholarship on environmental communication as a subdiscipline of communication studies focused on mass media. However, these reviews may not provide a full picture of the field. We searched one of the most comprehensive citation databases (Scopus) for articles published from 1970 to 2019 containing the root terms environment* communicat*. The dataset ( n = 474) revealed an increase over time in the number of journals that publish environmental communication studies and the breadth of their National Science Foundation disciplinary categorizations. Climate communication, corporate social responsibility, and public engagement and participation represent the most frequent abstract topics. Through co-citation analysis of journals cited in references, we found that the foundational literatures informing the field have grown into dense, interconnected networks across disparate areas of scholarship that span the social sciences, natural sciences, engineering, and business. This disciplinary convergence is a positive sign for the field’s potential to address problems of societal importance.
Journal Article
Short-term habituation of auditory evoked potential and neuromagnetic field components in dependence of the interstimulus interval
by
Zimmerer, Karen
,
Rosburg, Timm
,
Huonker, Ralph
in
Acoustic Stimulation - methods
,
Adult
,
Auditory cortex
2010
Repeated auditory stimulation results usually in a response decrement of event-related potential components. In the current study, we investigated the impact of the interstimulus interval (ISI) on the response decrement. Healthy subjects were stimulated with trains of five tones, with an ISI of 600, 1,200, or 1,800 ms within the trains. Auditory evoked potentials (AEP) were recorded from the vertex, as well as neuromagnetic auditory evoked fields (AEF) from the left temporal region. Stimulus repetition led to a response decrement for the studied AEP components (N100 and P200) and AEF components (N100m and P200m). However, for all used ISIs, there was no further response decrement after the 2nd stimulus. The ISI affected only the magnitude but not the kind of the response decrement. No evidence for a gradual response decrement was revealed at any used ISI. This finding indicates that the response decrement is probably due to the refractoriness of cell assemblies involved in the generation of AEP and AEF components, rather than the result of a genuine habituation process. The finding questions habituation as the mechanism behind short-term decrements of AEP/AEF components.
Journal Article