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1.
Mayo Clin Proc ; 99(9): 1351-1353, 2024 Sep.
Article in English | MEDLINE | ID: mdl-39232619
2.
J Am Coll Emerg Physicians Open ; 5(5): e13303, 2024 Oct.
Article in English | MEDLINE | ID: mdl-39281726

ABSTRACT

Background: Point-of-care electroencephalography (EEG) devices can be rapidly applied and do not require specialized technologists, creating new opportunities to use EEG during prehospital care. We evaluated the feasibility of point-of-care EEG during ambulance transport for 911 calls. Methods: This mixed-methods study was conducted between May 28, 2022 and October 28, 2023. Emergency Medical Services (EMS) clinicians identified eligible individuals, provided emergent treatment, applied EEG, and obtained an EEG recording during ambulance transport. Eligible patients were aged 6 years or older and evaluated for seizure, stroke, or altered mental status. EMS clinicians completed a survey and a brief phone interview following every enrollment. Two epileptologists reviewed EEG recordings for interpretability and artifact. Results: There were 34 prehospital encounters in which EEG was applied. Patients had a mean age of 69 years, and 15 (44%) were female. EEG recordings had a median duration of 10 min 30 s. It took EMS clinicians an average of 2.5 min to apply the device and begin EEG recording. There were 14 (47%) recordings where clinicians achieved a high-quality connection for all 10 electrodes and 32 (94%) recordings that were sufficient in quality to interpret. There were 24 (71%) recordings with six or more channels free of artifact for 5 min or more. All clinicians agreed or strongly agreed that the device was easy to use. Conclusion: Among real-world prehospital encounters for patients with neurologic symptoms, point-of-care EEG was rapidly applied and yielded EEG recordings that could be used for clinical interpretation, demonstrating the feasibility of point-of-care EEG in future prehospital care.

3.
Bioorg Med Chem ; 113: 117907, 2024 Sep 06.
Article in English | MEDLINE | ID: mdl-39288704

ABSTRACT

CYP5122A1, an enzyme involved in sterol biosynthesis in Leishmania, was recently characterized as a sterol C4-methyl oxidase. Screening of a library of compounds against CYP5122A1 and CYP51 from Leishmania resulted in the identification of two structurally related classes of inhibitors of these enzymes. Analogs of screening hit N-(3,5-dimethylphenyl)-4-(pyridin-4-ylmethyl)piperazine-1-carboxamide (4a) were generally strong inhibitors of CYP51 but were less potent against CYP5122A1 and typically displayed weak inhibition of L. donovani promastigote growth. Analogs of screening hit N-(4-(benzyloxy)phenyl)-4-(2-(pyridin-4-yl)ethyl)piperazine-1-carboxamide (18a) were stronger inhibitors of both CYP5122A1 and L. donovani promastigote proliferation but also remained selective for inhibition of CYP51. Two compounds in this series, N-(4-((3,5-bis(trifluoromethyl)benzyl)oxy)phenyl)-4-(2-(pyridin-4-yl)ethyl)piperazine-1-carboxamide (18e) and N-(4-((3,5-di-tert-butylbenzyl)oxy)phenyl)-4-(2-(pyridin-4-yl)ethyl)piperazine-1-carboxamide (18i) showed modest selectivity for inhibiting L. donovani promastigote proliferation compared to J774 macrophages and were effective against intracellular L. donovani with EC50 values in the low micromolar range. Replacement of the 4-pyridyl ring present in 18e with imidazole resulted in a compound (4-(2-(1H-imidazol-1-yl)ethyl)-N-(4-((3,5-bis(trifluoromethyl)benzyl)oxy)phenyl)piperazine-1-carboxamide, 18p) with approximately fourfold selectivity for CYP5122A1 over CYP51 that inhibited both enzymes with IC50 values ≤ 1 µM, although selective potency against L. donovani promastigotes was lost. Compound 18p also inhibited the proliferation of L. major promastigotes and caused the accumulation of 4-methylated sterols in L. major membranes, indicating that this compound blocks sterol demethylation at the 4-position in Leishmania parasites. The molecules described here may therefore be useful for the future identification of dual inhibitors of CYP51 and CYP5122A1 as potential antileishmanial drug candidates and as probes to shed further light on sterol biosynthesis in Leishmania and related parasites.

5.
Microbiol Spectr ; : e0069424, 2024 Sep 09.
Article in English | MEDLINE | ID: mdl-39248479

ABSTRACT

Pseudomonas aeruginosa is a highly problematic opportunistic pathogen that causes a range of different infections. Infections are commonly treated with ß-lactam antibiotics, including cephalosporins, monobactams, penicillins, and carbapenems, with carbapenems regarded as antibiotics of last resort. Isolates of P. aeruginosa can contain horizontally acquired bla genes encoding ß-lactamase enzymes, but the extent to which these contribute to ß-lactam resistance in this species has not been systematically quantified. The overall aim of this research was to address this knowledge gap by quantifying the frequency of ß-lactamase-encoding genes in P. aeruginosa and by determining the effects of ß-lactamases on susceptibility of P. aeruginosa to ß-lactams. Genome analysis showed that ß-lactamase-encoding genes are present in 3% of P. aeruginosa but are enriched in carbapenem-resistant isolates (35%). To determine the substrate antibiotics, 10 ß-lactamases were expressed from an integrative plasmid in the chromosome of P. aeruginosa reference strain PAO1. The ß-lactamases reduced susceptibility to a variety of clinically used antibiotics, including carbapenems (meropenem, imipenem), penicillins (ticarcillin, piperacillin), cephalosporins (ceftazidime, cefepime), and a monobactam (aztreonam). Different enzymes acted on different ß-lactams. ß-lactamases encoded by the genomes of P. aeruginosa clinical isolates had similar effects to the enzymes expressed in strain PAO1. Genome engineering was used to delete ß-lactamase-encoding genes from three carbapenem-resistant clinical isolates and increased susceptibility to substrate ß-lactams. Our findings demonstrate that acquired ß-lactamases play an important role in ß-lactam resistance in P. aeruginosa, identifying substrate antibiotics for a range of enzymes and quantifying their contributions to resistance.IMPORTANCEPseudomonas aeruginosa is an extremely problematic pathogen, with isolates that are resistant to the carbapenem class of ß-lactam antibiotics being in critical need of new therapies. Genes encoding ß-lactamase enzymes that degrade ß-lactam antibiotics can be present in P. aeruginosa, including carbapenem-resistant isolates. Here, we show that ß-lactamase genes are over-represented in carbapenem-resistant isolates, indicating their key role in resistance. We also show that different ß-lactamases alter susceptibility of P. aeruginosa to different ß-lactam antibiotics and quantify the effects of selected enzymes on ß-lactam susceptibility. This research significantly advances the understanding of the contributions of acquired ß-lactamases to antibiotic resistance, including carbapenem resistance, in P. aeruginosa and by implication in other species. It has potential to expedite development of methods that use whole genome sequencing of infecting bacteria to inform antibiotic treatment, allowing more effective use of antibiotics, and facilitate the development of new antibiotics.

6.
Palliat Med ; : 2692163241277394, 2024 Sep 10.
Article in English | MEDLINE | ID: mdl-39254148

ABSTRACT

BACKGROUND: Advance care planning initiatives are becoming more widespread, increasing expectations for providers to engage in goals of care conversations. However, less is known about how providers communicate advance care planning within and throughout a health care system. AIM: To explore perspectives of communication processes in the rollout of an advance care planning initiative. DESIGN: Theoretically informed secondary analysis of 31 semi-structured interviews. SETTING/PARTICIPANTS: Key partners in a Veterans Health Administration goals of care initiative. RESULTS: Using the constant comparative approach followed by qualitative mapping of themes to the layers of the Socio-Ecological Model, four themes and corresponding Socio-Ecological layers were identified: Goals of Care Communication Training (Policy, Community, and Institutional) requires more resources across sites and better messaging to reduce provider misconceptions and promote an institutional culture invested in advance care planning; Interprofessional Communication (Interpersonal) suggests care team coordination is needed to facilitate continuity in goals of care messaging; Communication in Documentation (Institutional, Interpersonal, and Intrapersonal) highlights the need for capturing the context for goals of care preferences; and Patient/Family Communication (Interpersonal and Intrapersonal) encourages offering materials and informational resources early to facilitate rapport building and readiness to determine goals of care. CONCLUSIONS: Findings support the need for initiatives to incorporate an evaluation of how goals of care are discussed beyond the interpersonal exchange between patient and provider and signal opportunities for applying the Socio-Ecological Model to better understand goals of care communication processes, including opportunities to improve initiation and documentation of goals of care.

7.
Microbiology (Reading) ; 170(9)2024 Sep.
Article in English | MEDLINE | ID: mdl-39230258

ABSTRACT

Klebsiella pneumoniae is a pathogen of major concern in the global rise of antimicrobial resistance and has been implicated as a reservoir for the transfer of resistance genes between species. The upregulation of efflux pumps is a particularly concerning mechanism of resistance acquisition as, in many instances, a single point mutation can simultaneously provide resistance to a range of antimicrobials and biocides. The current study investigated mutations in oqxR, which encodes a negative regulator of the RND-family efflux pump genes, oqxAB, natively found in the chromosome of K. pneumoniae. Resistant mutants in four K. pneumoniae strains (KP6870155, NTUH-K2044, SGH10, and ATCC43816) were selected from single exposures to 30 µg/mL chloramphenicol and 12 mutants were selected for whole genome sequencing to identify mutations associated with resistance. Resistant mutants generated by single exposures to chloramphenicol, tetracycline, or ciprofloxacin at ≥4 X MIC were replica plated onto all three antibiotics to observe simultaneous cross-resistance to all compounds, indicative of a multidrug resistance phenotype. A variety of novel mutations, including single point mutations, deletions, and insertions, were found to disrupt oqxR leading to significant and simultaneous increases in resistance to chloramphenicol, tetracycline, and ciprofloxacin. The oqxAB-oqxR locus has been mobilized and dispersed on plasmids in many Enterobacteriaceae species and the diversity of these loci was examined to evaluate the evolutionary pressures acting on these genes. Comparison of the promoter regions of oqxR in plasmid-borne copies of the oqxR-oqxAB operon indicated that some constructs may produce truncated versions of the oqxR transcript, which may impact on oqxAB regulation and expression. In some instances, co-carriage of chromosomal and plasmid encoded oqxAB-oqxR was found in K. pneumoniae, implying that there is selective pressure to maintain and expand the efflux pump. Given that OqxR is a repressor of oqxAB, any mutation affecting its expression or function can lead to multidrug resistance. This is in contrast to antibiotic target site mutations that must occur in limited sequence space to be effective and not impact the fitness of the cell. Therefore, oqxR may act as a simple genetic switch to facilitate resistance via OqxAB mediated efflux.


Subject(s)
Anti-Bacterial Agents , Bacterial Proteins , Drug Resistance, Multiple, Bacterial , Klebsiella pneumoniae , Anti-Bacterial Agents/pharmacology , Bacterial Proteins/genetics , Bacterial Proteins/metabolism , Chloramphenicol/pharmacology , Ciprofloxacin/pharmacology , Drug Resistance, Bacterial , Gene Expression Regulation, Bacterial , Klebsiella Infections/microbiology , Klebsiella pneumoniae/genetics , Klebsiella pneumoniae/drug effects , Klebsiella pneumoniae/metabolism , Membrane Transport Proteins/genetics , Membrane Transport Proteins/metabolism , Microbial Sensitivity Tests , Mutation , Tetracycline/pharmacology , Whole Genome Sequencing
8.
ERJ Open Res ; 10(4)2024 Jul.
Article in English | MEDLINE | ID: mdl-39104957

ABSTRACT

Aim: Heritability of cough has not yet been studied. We aimed to evaluate if individuals with cough are more likely to have offspring who develop cough, and if these associations differ by type of cough (productive/nonproductive). Methods: The RHINESSA Generation Study (Respiratory Health In Northern Europe, Spain and Australia) includes 7155 parents (initially aged 30-54) answering detailed questionnaires in 2000 and 2010, and 8176 offspring ≥20 years answering similar questionnaires in 2012-2019. Chronic cough was categorised as productive or nonproductive (dry) cough. Associations between parental and offspring cough were analysed using mixed-effects logistic regression, adjusting for offspring age, sex, body mass index, smoking history, education level, current asthma, rhinitis, nocturnal gastroesophageal reflux; parent sex and smoking history; centre and family. Results: Among parents with nonproductive cough, 11% of their offspring reported nonproductive cough, compared with 7% of offspring to parents without nonproductive cough, adjusted odds ratio (aOR) 1.59 (95% confidence interval 1.20-2.10). Among parents with productive cough, 14% of their offspring reported productive cough, compared with 11% of offspring to parents without productive cough, aOR 1.34 (1.07-1.67). No associations were found between parent productive cough-offspring nonproductive cough, nor between parent nonproductive cough-offspring productive cough. Conclusions: Parents with chronic cough are more likely to have offspring with chronic cough independent of parental asthma, suggesting cough to be a separate heritable trait. The type of cough is important, as the nonproductive cough in parent associates only with nonproductive cough in offspring, and the same applied for productive cough.

9.
Elife ; 122024 Aug 27.
Article in English | MEDLINE | ID: mdl-39189918

ABSTRACT

Klebsiella pneumoniae is a global public health concern due to the rising myriad of hypervirulent and multidrug-resistant clones both alarmingly associated with high mortality. The molecular mechanisms underpinning these recalcitrant K. pneumoniae infection, and how virulence is coupled with the emergence of lineages resistant to nearly all present-day clinically important antimicrobials, are unclear. In this study, we performed a genome-wide screen in K. pneumoniae ECL8, a member of the endemic K2-ST375 pathotype most often reported in Asia, to define genes essential for growth in a nutrient-rich laboratory medium (Luria-Bertani [LB] medium), human urine, and serum. Through transposon directed insertion-site sequencing (TraDIS), a total of 427 genes were identified as essential for growth on LB agar, whereas transposon insertions in 11 and 144 genes decreased fitness for growth in either urine or serum, respectively. These studies not only provide further knowledge on the genetics of this pathogen but also provide a strong impetus for discovering new antimicrobial targets to improve current therapeutic options for K. pneumoniae infections.


Subject(s)
DNA Transposable Elements , Klebsiella pneumoniae , Urine , Klebsiella pneumoniae/genetics , Klebsiella pneumoniae/growth & development , Humans , DNA Transposable Elements/genetics , Urine/microbiology , Klebsiella Infections/microbiology , Klebsiella Infections/urine , Mutagenesis, Insertional , Serum/microbiology , Mutagenesis
10.
Ann Palliat Med ; 2024 Aug 05.
Article in English | MEDLINE | ID: mdl-39129523

ABSTRACT

BACKGROUND: Cultural competence is important in approaching serious illness communication with diverse patients about goals of care. Culture colors patients' perspectives on many healthcare issues, including end-of-life care, and impacts how clinicians make decisions with patients. Communication about serious neurological illnesses can be additionally challenging due to disease impact on patients' cognition and decision-making abilities. We aim to understand provider experiences regarding cross-cultural serious neurological illness communication with diverse patients and families. METHODS: Using non-stratified purposive and snowball sampling, we conducted semi-structured interviews with 17 multidisciplinary participants, including neurosurgeons, neurologists, and social workers, who provide care for patients diagnosed with serious neurological disorders, at three hospital settings between 2021 and 2022. We used standard qualitative content analysis methods with dual review. RESULTS: Five themes reflected provider perspectives about serious neurological illness communication with diverse patients and families. Theme 1: providers recognize that patients' personal biases and lived experiences impact attitudes about healthcare and communication. Theme 2: challenges in communication can arise when providers miss chances to identify important cultural values. Theme 3: understanding how to engage with family members is important for effective communication about serious neurological illness. Theme 4: providers want to accommodate patients. Theme 5: cultivating trust builds a strong patientprovider partnership, even when racial or cultural discordance is present. CONCLUSIONS: Our study highlights elements of cross-cultural communication and opportunities for providers to approach diverse patients and families within a racial or culturally discordant context. Effective communication, fostered through respecting individual experiences and variation, eliciting cultural perspectives, engaging family, and cultivating trust reflects processes and learned skills required of highquality teams caring for patients with serious neurological conditions.

11.
Accid Anal Prev ; 207: 107744, 2024 Nov.
Article in English | MEDLINE | ID: mdl-39121574

ABSTRACT

Bus driver sleepiness is commonplace but often goes unreported within the industry. Whilst past research has begun to shed a light on the prevalence, potential causes, and consequences of bus driver sleepiness, this is often done using self-report methods. This is the first study to investigate sleepiness amongst city bus drivers on-road using a live bus route with drivers' regular schedules. A total of 16 participants completed two drives of their regular bus route once during an early morning shift and once during a daytime shift whilst physiological and self-report measures of sleep and stress were taken. Prior to these drives, drivers recorded their sleep in a diary and wore an actigraph to obtain objective sleep measures. Results showed that most drivers did not obtain sufficient sleep prior to early morning shifts, and often did not obtain as much sleep as they would need in order to feel rested before work. Sleepiness and stress were observed in both shifts. During early morning shifts sleepiness was likely a result of working during circadian lows and not obtaining enough sleep prior to the shift. In contrast, sleepiness during the daytime shift was likely a result of completing a highly demanding task in complex traffic which not only contributed to fatigue, but also led to increased levels of stress. As well as demonstrating the prevalence of sleepiness amongst bus drivers, these findings show that the causes of sleepiness can be multifaceted and often come about due to a combination of work and personal factors. In addition, the experience of sleepiness is not the same for all drivers, with individual differences in the experience of sleepiness playing a large role. These differences highlight the need for individualised interventions which should be considered by policymakers alongside the combination of causal factors within a larger systems approach.


Subject(s)
Automobile Driving , Motor Vehicles , Humans , Male , Adult , Automobile Driving/psychology , Middle Aged , Female , London/epidemiology , Sleepiness , Actigraphy , Fatigue/physiopathology , Stress, Psychological , Work Schedule Tolerance/physiology , Sleep/physiology , Occupational Stress , Self Report
12.
J Colloid Interface Sci ; 677(Pt B): 293-302, 2024 Aug 08.
Article in English | MEDLINE | ID: mdl-39146817

ABSTRACT

In vitro and in vivo tests for therapeutic agents are typically conducted in sterile environments, but many target areas for drug delivery are home to thousands of microbial species. Here, we examine the behaviour of lipidic nanomaterials after exposure to representative strains of four bacterial species found in the gastrointestinal tract and skin. Small angle X-ray scattering measurements show that the nanostructure of monoolein cubic and inverse hexagonal phases are transformed, respectively, into inverse hexagonal and inverse micellar cubic phases upon exposure to a strain of live Staphylococcus aureus often present on skin and mucosa. Further investigation demonstrates that enzymatic hydrolysis and cell membrane lipid transfer are both likely responsible for this effect. The structural responses to S. aureus are rapid and significantly reduce the rate of drug release from monoolein-based nanomaterials. These findings are the first to demonstrate how a key species in the live human microbiome can trigger changes in the structure and drug release properties of lipidic nanomaterials. The effect appears to be strain specific, varies from patient to patient and body region to body region, and is anticipated to affect the bioapplication of monoglyceride-based formulations.

13.
Vaccines (Basel) ; 12(8)2024 Aug 01.
Article in English | MEDLINE | ID: mdl-39203990

ABSTRACT

Live attenuated influenza vaccines (LAIV) typically induce a poor hemagglutination inhibition (HI) response, which is the standard correlate of protection for inactivated influenza vaccines. The significance of the HI response is complicated because the LAIV vaccine primarily induces the local mucosal immune system, while the HI assay measures the circulating serum antibody response. However, age and pre-existing immunity have been identified as important factors affecting LAIV immunogenicity. This study aimed to extend our understanding of LAIV-induced immunity, particularly, the impact age and pre-existing immunity have on eliciting functional and neutralising antibody responses in paediatric and adult populations vaccinated with LAIV. Thirty-one children and 26 adults were immunized with the trivalent LAIV during the 2013-2014 influenza season in Norway. Children under 9 years received a second dose of LAIV 28 days after the first dose. Blood samples were collected pre- and post-vaccination. HI, microneutralization (MN) and enzyme-linked lectin assay for neuraminidase (NA) antibodies were measured against the vaccine strains. IgG antibody avidity against hemagglutinin (HA) and NA proteins from the vaccine strains was also assessed. Significant correlations were observed between HI and MN responses to A/California/7/2009 (A/H1N1)pdm09-like strain and B/Massachusetts/2/2012-like strain, suggesting that MN is a potential immunological correlate for LAIV. However, the relationship between recipient age (or priming status) and serological response varied between vaccine strains. There was a notable increase in HI and MN responses in all cohorts except naive children against the H1N1 strain, where most recipients had responses below the protective antibody threshold. NAI responses were generally weak in naive children against all vaccine strains compared with adults or antigen-primed children. Post-vaccination antibody avidity increased only in primed children below nine years of age against the A/H1N1 strain. Overall, our findings indicate that LAIV elicits functional and neutralizing antibody responses in both naive and antigen experienced cohorts, however, the magnitude and kinetics of the response varies between vaccine strains.

14.
BMJ Open Respir Res ; 11(1)2024 Jul 22.
Article in English | MEDLINE | ID: mdl-39038916

ABSTRACT

OBJECTIVES: To investigate the association of early snus use initiation (≤15 years of age) with asthma and asthma symptoms. DESIGN: Cross-sectional analysis of a population-based cohort. SETTING: Study centres in Norway, Sweden, Iceland, Denmark and Estonia, from 2016 to 2019. PARTICIPANTS: 9002 male and female participants above 15 years of age of the Respiratory Health in Northern Europe, Spain and Australia study. MAIN OUTCOME MEASURES: Current asthma and asthma symptoms. RESULTS: The median age of study participants was 28 years (range 15-53) and 58% were women. 20% had used snus, 29% men and 14% women. Overall, 26% of males and 14% of females using snus started ≤15 years of age. Early snus use initiation was associated with having three or more asthma symptoms (OR 2.70; 95% CI 1.46 to 5.00) and a higher asthma symptom score (ß-coefficient (ß) 0.35; 95% CI 0.07 to 0.63) in women. These associations were weak in men (OR 1.23; 95% CI 0.78 to 1.94; ß 0.16; 95% CI -0.06 to 0.38, respectively). There was evidence for an association of early snus initiation with current asthma (OR 1.72; 95% CI 0.88 to 3.37 in women; OR 1.31; 95% CI 0.84 to 2.06 in men). A sensitivity analysis among participants without smoking history showed stronger estimates for all three outcomes, in both men and women, statistically significant for three or more asthma symptoms in women (OR 3.28; 95% CI 1.18 to 9.10). Finally, no consistent associations with asthma outcomes were found for starting snus after age 15 years. CONCLUSIONS: Snus initiation in puberty was associated with higher likelihood of asthma and asthma symptoms, with the highest estimates in females and those without smoking history. These results raise concerns about the health adversities of early snus initiation and emphasise the need for public health initiatives to protect young people from this tobacco product.


Subject(s)
Asthma , Tobacco, Smokeless , Humans , Asthma/epidemiology , Female , Male , Adolescent , Cross-Sectional Studies , Adult , Young Adult , Tobacco, Smokeless/adverse effects , Middle Aged , Puberty
15.
Contemp Clin Trials ; 145: 107643, 2024 Oct.
Article in English | MEDLINE | ID: mdl-39074531

ABSTRACT

BACKGROUND: Goals of care conversations explore seriously ill patients' values to guide medical decision making and often inform decisions about life sustaining treatments. Ideally, conversations occur before a health crisis between patients and clinicians in the outpatient setting. In the United States Veterans Affairs (VA) healthcare system, most conversations still occur in the inpatient setting. Strategies are needed to improve implementation of outpatient, primary care goals of care conversations. METHODS: We plan a cluster randomized (clinician-level) sequential, multiple assignment randomized trial to evaluate the effectiveness of patient implementation strategies on the outcome of goals of care conversation documentation when delivered in combination with clinician implementation strategies. Across three VA healthcare system sites, we will enroll primary care clinicians with low rates of goals of care conversations and their patients with serious medical illness in the top 10th percentile of risk of hospitalization or death. We will compare the effectiveness of sequences of implementation strategies and explore how patient and site factors modify implementation strategy effects. Finally, we will conduct a mixed-methods evaluation to understand implementation strategy success or failure. The design includes two key innovations: (1) strategies that target both clinicians and patients and (2) sequential strategies with increased intensity for non-responders. CONCLUSION: This study aims to determine the effect of different sequences and combinations of implementation strategies on primary care documentation of goals of care conversations. Study partners, including the VA National Center for Ethics in Health Care and Office of Primary Care, can consider policies based on study findings.


Subject(s)
Communication , Patient Care Planning , Primary Health Care , United States Department of Veterans Affairs , Humans , Primary Health Care/organization & administration , United States Department of Veterans Affairs/organization & administration , Patient Care Planning/organization & administration , United States , Physician-Patient Relations
16.
J Antimicrob Chemother ; 79(9): 2170-2178, 2024 Sep 03.
Article in English | MEDLINE | ID: mdl-39001778

ABSTRACT

BACKGROUND: ß-lactam antibiotics, which inhibit penicillin-binding protein 3 (PBP3) that is required for cell division, play a key role in treating P. aeruginosa infections. Some sequence variations in PBP3 have been associated with ß-lactam resistance but the effects of variations on antibiotic susceptibility and on cell division have not been quantified. Antibiotic efflux can also reduce susceptibility. OBJECTIVES: To quantify the effects of PBP3 variations on ß-lactam susceptibility and cell morphology in P. aeruginosa. METHODS: Nineteen PBP3 variants were expressed from a plasmid in the reference strain P. aeruginosa PAO1 and genome engineering was used to construct five mutants expressing PBP3 variants from the chromosome. The effects of the variations on ß-lactam minimum inhibitory concentration (MIC) and cell morphology were measured. RESULTS: Some PBP3 variations reduced susceptibility to a variety of ß-lactam antibiotics including meropenem, ceftazidime, cefepime and ticarcillin with different variations affecting different antibiotics. None of the tested variations reduced susceptibility to imipenem or piperacillin. Antibiotic susceptibility was further reduced when PBP3 variants were expressed in mutant bacteria overexpressing the MexAB-OprM efflux pump, with some variations conferring clinical levels of resistance. Some PBP3 variations, and sub-MIC levels of ß-lactams, reduced bacterial growth rates and inhibited cell division, causing elongated cells. CONCLUSIONS: PBP3 variations in P. aeruginosa can increase the MIC of multiple ß-lactam antibiotics, although not imipenem or piperacillin. PBP3 variations, or the presence of sub-lethal levels of ß-lactams, result in elongated cells indicating that variations reduce the activity of PBP3 and may reduce bacterial fitness.


Subject(s)
Anti-Bacterial Agents , Cell Division , Microbial Sensitivity Tests , Penicillin-Binding Proteins , Pseudomonas aeruginosa , beta-Lactams , Pseudomonas aeruginosa/drug effects , Pseudomonas aeruginosa/genetics , Penicillin-Binding Proteins/genetics , beta-Lactams/pharmacology , Anti-Bacterial Agents/pharmacology , Cell Division/drug effects , beta-Lactam Resistance/genetics , Genetic Variation , Plasmids/genetics
17.
bioRxiv ; 2024 May 20.
Article in English | MEDLINE | ID: mdl-38826221

ABSTRACT

Drug discovery starts with known function, either of a compound or a protein, in-turn prompting investigations to probe 3D structure of the compound-protein interface. As protein structure determines function, we hypothesized that unique 3D structural motifs represent primary information denoting unique function that can drive discovery of novel agents. Using a physics-based protein structure analysis platform developed by us, designed to conduct computationally intensive analysis at supercomputing speeds, we probed a high-resolution protein x-ray crystallographic library developed by us. We selected 3D structural motifs whose function was not otherwise established, that offered environments supporting binding of drug-like chemicals and were present on proteins that were not established therapeutic targets. For each of eight potential binding pockets on six different proteins we accessed a 60 million compound library and used our analysis platform to evaluate binding. Using eight-day colony formation assays acquired compounds were screened for efficacy against human breast, prostate, colon and lung cancer cells and toxicity against human bone marrow stem cells. Compounds selectively inhibiting cancer growth segregated to two pockets on separate proteins. The compound, Dxr2-017, exhibited selective activity against human melanoma cells in the NCI-60 cell line screen, had an IC50 of 19 nM against human melanoma M14 cells in our eight-day assay, while over 2100-fold higher concentrations inhibited stem cells by less than 30%. We show that Dxr2-017 induces anoikis, a unique form of programmed cell death in need of targeted therapeutics. The predicted target protein for Dxr2-017 is expressed in bacteria, not in humans. This supports our strategy of focusing on unique 3D structural motifs. It is known that functionally important 3D structures are evolutionarily conserved. Here we demonstrate proof-of-concept that protein structure represents high value primary data to support discovery of novel therapeutics. This approach is widely applicable.

18.
J Am Coll Radiol ; 21(6S): S100-S125, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38823940

ABSTRACT

Diagnostic evaluation of a patient with dizziness or vertigo is complicated by a lack of standardized nomenclature, significant overlap in symptom descriptions, and the subjective nature of the patient's symptoms. Although dizziness is an imprecise term often used by patients to describe a feeling of being off-balance, in many cases dizziness can be subcategorized based on symptomatology as vertigo (false sense of motion or spinning), disequilibrium (imbalance with gait instability), presyncope (nearly fainting or blacking out), or lightheadedness (nonspecific). As such, current diagnostic paradigms focus on timing, triggers, and associated symptoms rather than subjective descriptions of dizziness type. Regardless, these factors complicate the selection of appropriate diagnostic imaging in patients presenting with dizziness or vertigo. This document serves to aid providers in this selection by using a framework of definable clinical variants. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision process support the systematic analysis of the medical literature from peer reviewed journals. Established methodology principles such as Grading of Recommendations Assessment, Development, and Evaluation or GRADE are adapted to evaluate the evidence. The RAND/UCLA Appropriateness Method User Manual provides the methodology to determine the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where peer reviewed literature is lacking or equivocal, experts may be the primary evidentiary source available to formulate a recommendation.


Subject(s)
Dizziness , Societies, Medical , Dizziness/diagnostic imaging , Humans , United States , Ataxia/diagnostic imaging , Evidence-Based Medicine , Diagnosis, Differential
19.
J Am Coll Radiol ; 21(6S): S21-S64, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38823945

ABSTRACT

Cerebrovascular disease encompasses a vast array of conditions. The imaging recommendations for stroke-related conditions involving noninflammatory steno-occlusive arterial and venous cerebrovascular disease including carotid stenosis, carotid dissection, intracranial large vessel occlusion, and cerebral venous sinus thrombosis are encompassed by this document. Additional imaging recommendations regarding complications of these conditions including intraparenchymal hemorrhage and completed ischemic strokes are also discussed. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision process support the systematic analysis of the medical literature from peer reviewed journals. Established methodology principles such as Grading of Recommendations Assessment, Development, and Evaluation or GRADE are adapted to evaluate the evidence. The RAND/UCLA Appropriateness Method User Manual provides the methodology to determine the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where peer reviewed literature is lacking or equivocal, experts may be the primary evidentiary source available to formulate a recommendation.


Subject(s)
Evidence-Based Medicine , Societies, Medical , Stroke , Humans , Stroke/diagnostic imaging , United States , Cerebrovascular Disorders/diagnostic imaging
20.
Prehosp Emerg Care ; : 1-7, 2024 Jul 11.
Article in English | MEDLINE | ID: mdl-38935488

ABSTRACT

OBJECTIVES: Medical Priority Dispatch System (MPDS) is a system used to assign medical 9-1-1 calls to one of 35 chief complaints that are further categorized in order of increasing priority, Alpha through Echo. In this descriptive study we demonstrate the methodology of matching MPDS codes to a county mortality registry. We also evaluated the ability of select MPDS codes (fall, respiratory, sick person, and abdominal pain) to predict mortality up to 30 d for all ages transported by Alameda County Emergency Medical Services (EMS). METHODS: Using Alameda County EMS data, we conducted a retrospective review of all EMS encounters that occurred from November 1, 2011, to November 1, 2016. To describe mortality in this population, we identified unique patients and linked them to the Alameda County Public Health Death Registry. We identified mortality at 48 h, 7 d, and 30 d after an EMS encounter. RESULTS: Approximately 99% of the EMS encounters were matched with unique patient identifiers, yielding a study sample of 202,431 (4% less than age 18, 53% between ages 18-65, and 43% over age 65). Patients with a respiratory chief complaint had the highest mortality percentage in each age group (0.23%, 2.7%, and 14.55% respectively). There was no correlation between the MPDS code and mortality for patients less than age 18. An increase in Alpha through Echo designation for respiratory complaints in patients 18-65 and older than 65 years corresponded with an increase in 30-day mortality. CONCLUSIONS: This study demonstrates an upward trend in mortality with increasing acuity of Alpha through Echo designations for adult patients with respiratory complaints. Mortality increased with age in this cohort. Most of the deaths occurred after 7 days.

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