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1.
Appl Environ Microbiol ; 90(5): e0028624, 2024 May 21.
Article in English | MEDLINE | ID: mdl-38624196

ABSTRACT

Host-parasite interactions are highly susceptible to changes in temperature due to mismatches in species thermal responses. In nature, parasites often exist in communities, and responses to temperature are expected to vary between host-parasite pairs. Temperature change thus has consequences for both host-parasite dynamics and parasite-parasite interactions. Here, we investigate the impact of warming (37°C, 40°C, and 42°C) on parasite life-history traits and competition using the opportunistic bacterial pathogen Pseudomonas aeruginosa (host) and a panel of three genetically diverse lytic bacteriophages (parasites). We show that phages vary in their responses to temperature. While 37°C and 40°C did not have a major effect on phage infectivity, infection by two phages was restricted at 42°C. This outcome was attributed to disruption of different phage life-history traits including host attachment and replication inside hosts. Furthermore, we show that temperature mediates competition between phages by altering their competitiveness. These results highlight phage trait variation across thermal regimes with the potential to drive community dynamics. Our results have important implications for eukaryotic viromes and the design of phage cocktail therapies.IMPORTANCEMammalian hosts often elevate their body temperatures through fevers to restrict the growth of bacterial infections. However, the extent to which fever temperatures affect the communities of phages with the ability to parasitize those bacteria remains unclear. In this study, we investigate the impact of warming across a fever temperature range (37°C, 40°C, and 42°C) on phage life-history traits and competition using a bacterium (host) and bacteriophage (parasite) system. We show that phages vary in their responses to temperature due to disruption of different phage life-history traits. Furthermore, we show that temperature can alter phage competitiveness and shape phage-phage competition outcomes. These results suggest that fever temperatures have the potential to restrict phage infectivity and drive phage community dynamics. We discuss implications for the role of temperature in shaping host-parasite interactions more widely.


Subject(s)
Pseudomonas aeruginosa , Pseudomonas aeruginosa/virology , Pseudomonas aeruginosa/physiology , Bacteriophages/physiology , Hot Temperature , Pseudomonas Phages/physiology , Pseudomonas Phages/growth & development , Life History Traits , Temperature
2.
Br J Clin Pharmacol ; 2024 Apr 16.
Article in English | MEDLINE | ID: mdl-38627909

ABSTRACT

The rise of psychedelics in contemporary medicine has sparked interest in their potential therapeutic applications. While traditionally associated with countercultural movements and recreational use, recent research has shed light on the potential benefits of psychedelics in various mental health conditions. In this review, we explore the possible role of psychedelics in the management of chronic pain and opioid use disorder (OUD), 2 critical areas in need of innovative treatment options. Pain control remains a significant clinical challenge, particularly for individuals with OUD and those who receive long-term opioid therapy who develop marked tolerance to opioid-induced analgesia. Despite the magnitude of this problem, there is a scarcity of controlled studies investigating pain management alternatives for these populations. Drawing from preclinical and human evidence, we highlight the potential of psychedelics to act on shared neurobiological substrates of chronic pain and OUD, potentially reversing pain- and opioid-induced neuroadaptations, such as central sensitization. We elaborate on the multifaceted dimensions of the pain experience (sensory, affective and cognitive) and their intersections that overlap with opioid-related phenomena (opioid craving and withdrawal), hypothesizing how these processes can be modulated by psychedelics. After summarizing the available clinical research, we propose mechanistic insights and methodological considerations for the design of future translational studies and clinical trials, building on a shared clinical and neurobiological understanding of chronic pain and OUD. Our intention is to provide timely perspectives that accelerate the development and exploration of novel therapeutics for chronic pain and OUD amidst the escalating opioid crisis.

3.
Br J Clin Pharmacol ; 2024 Mar 04.
Article in English | MEDLINE | ID: mdl-38439592

ABSTRACT

AIMS: Despite a strong theoretical link between opioid craving and pain, little is known about the temporal relationship between pain and craving and the acute experience of pain in the context of methadone treatment. Using a cross-over design, the current study evaluated the time course of pain and craving and objective experience of pain as a function of the last methadone dose. METHODS: Participants (n = 20) presented for the study in the morning and either received methadone dose as scheduled or delayed dose until the afternoon. During the 4-h study visit, participants completed a series of tasks, including repeated assessment of pain and craving at 0, +40, +70, +130, +160 and +240 min and a cold pressor test (CPT) at +15 and +220 min. RESULTS: Separate mixed model results demonstrated no effect of dosing condition on craving; however, there was a significant dosing condition by time interaction (F(5,209) = 3.38, P = .006) such that pain increased over time in the delayed methadone condition but decreased in time in the scheduled methadone condition. A mixed model predicting self-reported pain revealed a three-way interaction between dosing condition, craving and time (F(5,197) = 2.39, P = .039) explained by a positive association between craving and pain at each time point (except 240 min) in delayed condition (P-range = .004-.0001). A separate mixed model on CPT data indicated a significant condition by time interaction such that pain threshold decreased in the delayed, but not scheduled, condition (F(1,57) = 4.01, P = .050). CONCLUSIONS: These preliminary findings highlight the potential for increased risks after even a short delay in receiving a methadone dose.

4.
JMIR Res Protoc ; 13: e54342, 2024 Mar 20.
Article in English | MEDLINE | ID: mdl-38506917

ABSTRACT

BACKGROUND: Chronic pain is common among individuals with opioid use disorder (OUD) who are maintained on medications for OUD (MOUD; eg, buprenorphine or methadone). Chronic pain is associated with worse retention and higher levels of substance use. Treatment of individuals with chronic pain receiving MOUD can be challenging due to their increased clinical complexity. Given the acute and growing nature of the opioid crisis, MOUD is increasingly offered in a wide range of settings, where high-quality, clinician-delivered, empirically validated behavioral treatment for chronic pain may not be available. Therefore, digital treatments that support patient self-management of chronic pain and OUD have the potential for wider implementation to fill this gap. OBJECTIVE: This study aims to evaluate the efficacy of Integrating the Management of Pain and Addiction via Collaborative Treatment (IMPACT), an interactive digital treatment program with asynchronous coach feedback, compared to treatment as usual (TAU) in individuals with chronic pain and OUD receiving MOUD. METHODS: Adult participants (n=160) receiving MOUD and reporting bothersome or high-impact chronic pain will be recruited from outpatient opioid treatment programs in Connecticut (United States) and randomized 1:1 to either IMPACT+TAU or TAU only. Participants randomized to IMPACT+TAU will complete an interactive digital treatment that includes 9 modules promoting training in pain and addiction coping skills and a progressive walking program. The program is augmented with a weekly personalized voice message from a trained coach based on daily participant-reported pain intensity and interference, craving to use opioids, sleep quality, daily steps, pain self-efficacy, MOUD adherence, and engagement with IMPACT collected through digital surveys. Outcomes will be assessed at 3, 6, and 9 months post randomization. The primary outcome is MOUD retention at 3 months post randomization (ie, post treatment). Secondary outcomes include pain interference, physical functioning, MOUD adherence, substance use, craving, pain intensity, sleep disturbance, pain catastrophizing, and pain self-efficacy. Semistructured qualitative interviews with study participants (n=34) randomized to IMPACT (completers and noncompleters) will be conducted to evaluate the usability and quality of the program and its outcomes. RESULTS: The study has received institutional review board approval and began recruitment at 1 site in July 2022. Recruitment at a second site started in January 2023, with a third and final site anticipated to begin recruitment in January 2024. Data collection is expected to continue through June 2025. CONCLUSIONS: Establishing efficacy for a digital treatment for addiction and chronic pain that can be integrated into MOUD clinics will provide options for individuals with OUD, which reduce barriers to behavioral treatment. Participant feedback on the intervention will inform updates or modifications to improve engagement and efficacy. TRIAL REGISTRATION: ClinicalTrials.gov NCT05204576; https://clinicaltrials.gov/ct2/show/NCT05204576. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/54342.

5.
Nat Commun ; 15(1): 2610, 2024 Mar 23.
Article in English | MEDLINE | ID: mdl-38521779

ABSTRACT

The rise of antibiotic resistance is a critical public health concern, requiring an understanding of mechanisms that enable bacteria to tolerate antimicrobial agents. Bacteria use diverse strategies, including the amplification of drug-resistance genes. In this paper, we showed that multicopy plasmids, often carrying antibiotic resistance genes in clinical bacteria, can rapidly amplify genes, leading to plasmid-mediated phenotypic noise and transient antibiotic resistance. By combining stochastic simulations of a computational model with high-throughput single-cell measurements of blaTEM-1 expression in Escherichia coli MG1655, we showed that plasmid copy number variability stably maintains populations composed of cells with both low and high plasmid copy numbers. This diversity in plasmid copy number enhances the probability of bacterial survival in the presence of antibiotics, while also rapidly reducing the burden of carrying multiple plasmids in drug-free environments. Our results further support the tenet that multicopy plasmids not only act as vehicles for the horizontal transfer of genetic information between cells but also as drivers of bacterial adaptation, enabling rapid modulation of gene copy numbers. Understanding the role of multicopy plasmids in antibiotic resistance is critical, and our study provides insights into how bacteria can transiently survive lethal concentrations of antibiotics.


Subject(s)
Anti-Bacterial Agents , Escherichia coli , Plasmids/genetics , Anti-Bacterial Agents/pharmacology , Drug Resistance, Microbial/genetics , Escherichia coli/genetics , Gene Dosage , Drug Resistance, Bacterial/genetics
6.
Br J Clin Pharmacol ; 2023 Nov 22.
Article in English | MEDLINE | ID: mdl-37990580

ABSTRACT

A re-examination of clinical principles of long-term opioid therapy (LTOT) for chronic pain is long overdue amid the ongoing opioid crisis. Most patients on LTOT report ineffectiveness (poor pain control, function and health) but still find deprescribing challenging. Although prescribed as analgesics, opioids more likely provide pain relief primarily through reward system actions (enhanced relief and motivation) and placebo effect and less through antinociceptive effects. The unavoidable physiologic LTOT dependence can automatically lead to a paradoxical worsening of pain, disability and medical instability (maladaptive opioid dependence) without addiction due to allostatic opponent neuroadaptations involving reward/antireward and nociceptive/antinociceptive systems. This opioid-induced chronic pain syndrome (OICP) can persist/progress whether LTOT dose is maintained at the same level, increased, decreased or discontinued. Current conceptualization of LTOT as a straightforward long-term analgesic therapy appears incongruous in view of the complex mechanisms of opioid action, LTOT dependence and OICP. LTOT can be more appropriately conceptualized as therapeutic induction and maintenance of an adaptive LTOT dependence for functional improvement irrespective of analgesic benefits. Adaptive LTOT dependence should be ideally used for a limited time to achieve maximum functional recovery and deprescribed while maintaining functional gains. Patients on LTOT should be regularly re-evaluated to identify if maladaptive LTOT dependence with OICP has diminished any functional gains or leads to ineffectiveness. Ineffective LTOT (with maladaptive LTOT dependence) should be modified to make it safer and more effective. An adequately functional life without opioids is the ideal healthy long-term goal for both LTOT initiation and LTOT modification.

7.
ISME J ; 17(11): 2058-2069, 2023 11.
Article in English | MEDLINE | ID: mdl-37723338

ABSTRACT

Antibiotic resistance tends to carry fitness costs, making it difficult to understand how resistance can be maintained in the absence of continual antibiotic exposure. Here we investigate this problem in the context of mcr-1, a globally disseminated gene that confers resistance to colistin, an agricultural antibiotic that is used as a last resort for the treatment of multi-drug resistant infections. Here we show that regulatory evolution has fine-tuned the expression of mcr-1, allowing E. coli to reduce the fitness cost of mcr-1 while simultaneously increasing colistin resistance. Conjugative plasmids have transferred low-cost/high-resistance mcr-1 alleles across an incredible diversity of E. coli strains, further stabilising mcr-1 at the species level. Regulatory mutations were associated with increased mcr-1 stability in pig farms following a ban on the use of colistin as a growth promoter that decreased colistin consumption by 90%. Our study shows how regulatory evolution and plasmid transfer can combine to stabilise resistance and limit the impact of reducing antibiotic consumption.


Subject(s)
Colistin , Escherichia coli Proteins , Animals , Swine , Colistin/pharmacology , Escherichia coli/genetics , Escherichia coli/metabolism , Escherichia coli Proteins/genetics , Escherichia coli Proteins/metabolism , Drug Resistance, Bacterial/genetics , Anti-Bacterial Agents/pharmacology , Bacteria/genetics , Plasmids/genetics , Microbial Sensitivity Tests
8.
Curr Opin Microbiol ; 75: 102368, 2023 10.
Article in English | MEDLINE | ID: mdl-37677865

ABSTRACT

Infections that involve interkingdom microbial communities, such as those between bacteria and yeast pathogens, are difficult to treat, associated with worse patient outcomes, and may be a source of antimicrobial resistance. In this review, we address co-occurrence and co-infections of Candida albicans and Pseudomonas aeruginosa, two pathogens that occupy multiple infection niches in the human body, especially in immunocompromised patients. The interaction between the pathogen species influences microbe-host interactions, the effectiveness of antimicrobials and even infection outcomes, and may thus require adapted treatment strategies. However, the molecular details of bacteria-fungal interactions both inside and outside the infection sites, are insufficiently characterised. We argue that comprehensively understanding the P. aeruginosa-C. albicans interaction network through integrated systems biology approaches will capture the highly dynamic and complex nature of these polymicrobial infections and lead to a more comprehensive understanding of clinical observations such as reshaped immune defences and low antimicrobial treatment efficacy.


Subject(s)
Anti-Infective Agents , Coinfection , Humans , Candida albicans , Pseudomonas aeruginosa/genetics , Host Microbial Interactions
9.
Nat Commun ; 14(1): 4083, 2023 07 12.
Article in English | MEDLINE | ID: mdl-37438338

ABSTRACT

Antibiotic resistance poses a global health threat, but the within-host drivers of resistance remain poorly understood. Pathogen populations are often assumed to be clonal within hosts, and resistance is thought to emerge due to selection for de novo variants. Here we show that mixed strain populations are common in the opportunistic pathogen P. aeruginosa. Crucially, resistance evolves rapidly in patients colonized by multiple strains through selection for pre-existing resistant strains. In contrast, resistance evolves sporadically in patients colonized by single strains due to selection for novel resistance mutations. However, strong trade-offs between resistance and growth rate occur in mixed strain populations, suggesting that within-host diversity can also drive the loss of resistance in the absence of antibiotic treatment. In summary, we show that the within-host diversity of pathogen populations plays a key role in shaping the emergence of resistance in response to treatment.


Subject(s)
Patients , Humans , Drug Resistance, Microbial/genetics
10.
Cureus ; 15(6): e40868, 2023 Jun.
Article in English | MEDLINE | ID: mdl-37489219

ABSTRACT

BACKGROUND: Pregnancy, a unique physiologic state, is associated with several changes in the various body systems. The cardiovascular system is one of the systems affected, with chronic volume overload being one of the characteristic changes experienced during pregnancy. Cardiovascular disease in pregnancy is the leading cause of non-obstetric maternal death worldwide. AIM: This study aims to determine and describe the changes in left and right ventricular and atrial sizes in systole and diastole in the course of normal pregnancy. METHODS AND MATERIALS: A cohort study was conducted among healthy pregnant women between the age of 18 and 40 who attended the antenatal clinic of Federal Medical Centre (FMC), Yenagoa, Bayelsa State. Fifty women were recruited during the first trimester (T1) of pregnancy and followed up until six weeks postpartum. Ethical approval was obtained from the Research Ethics Committee of Federal Medical Centre, Yenagoa, with approval number FMCY/REC/ECC/2019/JAN/150. Clinical evaluation, hematologic, biochemical, and anthropometric assessments, and two-dimensional M-mode and Doppler echocardiography were done for the participants in each trimester of pregnancy and at six weeks postpartum. The clinical and echocardiographic parameters were analyzed using Statistical Package for the Social Sciences (SPSS) version 22.0 (IBM Corp., Armonk, NY, USA). RESULTS: The mean trend of left ventricular posterior wall thickness in diastole (LVPWd) and left ventricular posterior wall thickness in systole (LVPWs) increased progressively from the first to third trimester (T3) (not statistically significant) but dropped toward initial values in postpartum to the level that was statistically significant for LVWPd alone when compared to baseline first trimester values. The left atrial diameter in systole (LADs) was largest in the third trimester, and the left atrial volume index (LAVI) and right ventricular basal diameter (RVD1) also showed a similar trend. The left ventricular internal diameter (LVID) in both systole and diastole increased progressively from the first to the third trimesters, but the increase was only statistically significant between the third trimester (T3) and the first trimester (T1). The right atrial diameter (RAD) and right atrial volume (RAV) also increased progressively from the first to the third trimesters, but the increase was only statistically significant between the third trimester (T3) and the first trimester (T1). CONCLUSION: Changes were noticed in the cardiac chamber sizes during pregnancy. However, this reversed back to levels similar to the first trimester during the postpartum period. To aid in the early detection and treatment of cardiovascular disorders in pregnancy, screening of apparently healthy pregnant women who later developed complaints is advised as cardiovascular changes could be significant during pregnancy.

11.
BMC Public Health ; 23(1): 1051, 2023 06 01.
Article in English | MEDLINE | ID: mdl-37264375

ABSTRACT

BACKGROUND: The 95-95-95 UNAIDS global strategy was adapted to end the AIDS epidemic by 2030. The target is based on the premise that early detection of HIV-infected persons and linking them to treatment regardless of their CD4 counts will lead to sustained viral suppression. HIV testing strategies to increase uptake of testing in Western and Central Africa remain inadequate. Hence, a high proportion of people living with HIV in this region do not know their status. This report describes the implementation of a community based multi-disease health screening (also known as "Know Your Status" -KYS), as part of basic science research, in a way that contributed to achieving public health goals. METHODS: A community based multi-disease health screening was conducted in 7 communities within the Eastern region of Ghana between November 2017 and April 2018, to recruit and match HIV seronegative persons to HIV seropositive persons in a case-control HIV gut microbiota study. Health assessments included blood pressure, body mass index, blood sugar, Hepatitis B virus, syphilis, and HIV testing for those who consented. HIV seronegative participants who consented were consecutively enrolled in an ongoing HIV gut microbiota case-control study. Descriptive statistics (percentages) were used to analyze data. RESULTS: Out of 738 people screened during the exercise, 700 consented to HIV testing and 23 (3%) were HIV positive. Hepatitis B virus infection was detected in 4% (33/738) and Syphilis in 2% (17/738). Co-infection of HIV and HBV was detected in 4 persons. The HIV prevalence of 3% found in these communities is higher than both the national prevalence of 1.7% and the Eastern Regional prevalence of 2.7 in 2018. CONCLUSION: Community based multi-disease health screening, such as the one undertaken in our study could be critical for identifying HIV infected persons from the community and linking them to care. In the case of HIV, it will greatly contribute to achieving the first two 95s and working towards ending AIDS by 2030.


Subject(s)
HIV Infections , Mass Screening , HIV Infections/diagnosis , HIV Infections/epidemiology , Early Diagnosis , Prevalence , Continuity of Patient Care , Mass Screening/methods , Hepatitis B/diagnosis , Syphilis/diagnosis , Cross-Sectional Studies , Humans , Male , Female , Adult , Community Health Services , HIV Testing , Coinfection/epidemiology , Ghana/epidemiology
12.
Front Psychol ; 14: 1173641, 2023.
Article in English | MEDLINE | ID: mdl-37205082

ABSTRACT

Background: Chronic pain and problematic substance use are commonly co-occurring and highly detrimental issues that are especially prevalent in U.S. veteran populations. Although COVID-19 made clinical management of these conditions potentially difficult, some research suggests that certain veterans with these conditions did not experience this period as negatively as others. It is thus important to consider whether resilience factors, such as the increasingly-studied process of psychological flexibility, might have led to better outcomes for veterans managing pain and problematic substance use during this time of global crisis. Methods: This planned sub-analysis of a larger cross-sectional, anonymous, and nationally-distributed survey (N = 409) was collected during the first year of the COVID-19 pandemic. Veteran participants completed a short screener and battery of online surveys assessing pain severity and interference, substance use, psychological flexibility, mental health functioning, and pandemic-related quality of life. Results: For veterans with chronic pain and problematic substance use, the pandemic resulted in a significant lowering of their quality of life related to meeting basic needs, emotional health, and physical health compared to veterans with problematic substance use but no chronic pain diagnosis. However, moderation analyses revealed that veterans with these comorbid conditions experienced less negative impacts from the pandemic on quality of life and mental health when they reported greater psychological flexibility. For veterans with problematic substance use only, psychological flexibility was also related to better mental health functioning, but did not significantly correlate with their quality of life. Conclusion: Results highlight how COVID-19 differentially impacted veterans with both problematic substance use and chronic pain, such that this group reported particularly negative impacts of the pandemic on multiple areas of quality of life. However, our findings further emphasize that psychological flexibility, a modifiable resiliency process, also buffered against some of the negative impacts of the pandemic on mental health and quality of life. Given this, future research into the impact of natural crises and healthcare management should investigate how psychological flexibility can be targeted to help increase resiliency for veterans with chronic pain and problematic substance use.

13.
Nucleic Acids Res ; 51(13): 6806-6818, 2023 07 21.
Article in English | MEDLINE | ID: mdl-37254807

ABSTRACT

Many novel traits such as antibiotic resistance are spread by plasmids between species. Yet plasmids have different host ranges. Restriction-modification systems (R-M systems) are by far the most abundant bacterial defense system and therefore represent one of the key barriers to plasmid spread. However, their effect on plasmid evolution and host range has been neglected. Here we analyse the avoidance of targets of the most abundant R-M systems (Type II) for complete genomes and plasmids across bacterial diversity. For the most common target length (6 bp) we show that target avoidance is strongly correlated with the taxonomic distribution of R-M systems and is greater in plasmid genes than core genes. We find stronger avoidance of R-M targets in plasmids which are smaller and have a broader host range. Our results suggest two different evolutionary strategies for plasmids: small plasmids primarily adapt to R-M systems by tuning their sequence composition, and large plasmids primarily adapt through the carriage of additional genes protecting from restriction. Our work provides systematic evidence that R-M systems are important barriers to plasmid transfer and have left their mark on plasmids over long evolutionary time.


Subject(s)
Bacteria , DNA Restriction-Modification Enzymes , DNA Restriction-Modification Enzymes/genetics , Plasmids/genetics , Bacteria/genetics , Adaptation, Physiological , Drug Resistance, Microbial
14.
Drug Alcohol Depend ; 246: 109857, 2023 05 01.
Article in English | MEDLINE | ID: mdl-37004461

ABSTRACT

BACKGROUND: Despite high co-occurrence, chronic pain is often unaddressed in treatment for opioid use disorder (OUD) and little is known about mechanisms that may underlie associations between pain and opioid use. Using an attentional bias (AB) task with both pain and opioid cues, we evaluated a cognitive bias modification (CBM) task administered during regularly scheduled medications for OUD (mOUD) dosing visits. The current study evaluated the feasibility, acceptability, and preliminary efficacy of the CBM task. Outcomes for AB tasks used traditional mean-based score and trial-level bias scores (TLBS). METHODS: In a double-blind, randomized controlled trial, 28 individuals with OUD and chronic pain engaged in mOUD were randomized to either CBM or an AB control condition and completed up to three tasks per week for four weeks. Standard AB task was completed at baseline and post-treatment. Participants completed feasibility and acceptability measures, and preliminary efficacy (i.e., change in AB) was assessed using ANOVA models. RESULTS: Participants attended 83.3% of scheduled sessions and generally reported the task was enjoyable, credible, and easy to complete. Preliminary results demonstrated a condition by time interaction highlighting a reduction in AB in the CBM group but not the control group in opioid TLBS variability (F[1,26]=5.01, p = .034) and pain TLBS towards (F[1,26]=6.42, p = .018) and pain TLBS variability (F[1,26]=5.24, p = .03). CONCLUSIONS: The current study supports integrating brief, computer-based tasks designed to reduce AB into mOUD clinical care. The preliminary results suggest that TLBS outcomes may be more sensitive to capture changes in AB; however, larger studies are required.


Subject(s)
Buprenorphine , Chronic Pain , Opioid-Related Disorders , Humans , Analgesics, Opioid/therapeutic use , Cues , Chronic Pain/drug therapy , Chronic Pain/psychology , Feasibility Studies , Opioid-Related Disorders/drug therapy , Opioid-Related Disorders/psychology , Cognition , Buprenorphine/therapeutic use , Opiate Substitution Treatment/methods , Methadone/therapeutic use
15.
mBio ; 14(2): e0253722, 2023 04 25.
Article in English | MEDLINE | ID: mdl-36840554

ABSTRACT

Integrons are mobile genetic elements that have played an important role in the dissemination of antibiotic resistance. Under stress, the integron can generate combinatorial variation in resistance cassette expression by cassette reshuffling, accelerating the evolution of resistance. However, the flexibility of the integron integrase site recognition motif hints at potential off-target effects of the integrase on the rest of the genome that may have important evolutionary consequences. Here, we test this hypothesis by selecting for increased-piperacillin-resistance populations of Pseudomonas aeruginosa with a mobile integron containing a difficult-to-mobilize ß-lactamase cassette to minimize the potential for adaptive cassette reshuffling. We found that integron activity can decrease the overall survival rate but also improve the fitness of the surviving populations. Off-target inversions mediated by the integron accelerated plasmid adaptation by disrupting costly conjugative genes otherwise mutated in control populations lacking a functional integrase. Plasmids containing integron-mediated inversions were associated with lower plasmid costs and higher stability than plasmids carrying mutations albeit at the cost of a reduced conjugative ability. These findings highlight the potential for integrons to create structural variation that can drive bacterial evolution, and they provide an interesting example showing how antibiotic pressure can drive the loss of conjugative genes. IMPORTANCE Tackling the public health challenge created by antibiotic resistance requires understanding the mechanisms driving its evolution. Mobile integrons are widespread genetic platforms heavily involved in the spread of antibiotic resistance. Through the action of the integrase enzyme, integrons allow bacteria to capture, excise, and shuffle antibiotic resistance gene cassettes. This integrase enzyme is characterized by its ability to recognize a wide range of recombination sites, which allows it to easily capture diverse resistance cassettes but which may also lead to off-target reactions with the rest of the genome. Using experimental evolution, we tested the off-target impact of integron activity. We found that integrons increased the fitness of the surviving bacteria through extensive genomic rearrangements of the plasmids carrying the integrons, reducing their ability to spread horizontally. These results show that integrons not only accelerate resistance evolution but also can generate extensive structural variation, driving bacterial evolution beyond antibiotic resistance.


Subject(s)
Anti-Bacterial Agents , Integrons , Integrons/genetics , Anti-Bacterial Agents/pharmacology , Plasmids/genetics , Bacteria/genetics , Integrases/genetics
16.
Psychol Serv ; 20(1): 157-165, 2023 Feb.
Article in English | MEDLINE | ID: mdl-34968125

ABSTRACT

To address the ongoing opioid epidemic, there has been an increased focus on the treatment and evaluation of opioid use disorder (OUD). OUD and chronic pain (CP) frequently co-occur; however, little is known about the additional comorbidities that present when they occur together as compared to when either condition presents alone. Using data from Fiscal Year 2012 Veteran's Health Administration, all veterans diagnosed with both OUD + CP were compared to those diagnosed with OUD or CP alone on socioenvironmental characteristics, medical and mental health diagnoses, and Veterans Affairs (VA) clinical service use. Veterans with OUD + CP (n = 33,166), compared to those with OUD only (n = 12,517), had higher numbers of medical conditions. Compared to those with CP only (n = 2,015,368), veterans with OUD + CP had higher rates of homelessness and substance use diagnoses. Most mental health diagnoses, numbers of psychotropic medication fills, opioid prescriptions, and use of all other services were higher in the OUD + CP group than in either single disorder group. Multinomial regression analysis revealed stronger effects for medical disorders and medical-surgical outpatient service use in the comparison of OUD + CP with OUD only and stronger effects for substance use and mental health disorders and use of prescription opiates in the comparison with CP only. These findings suggest that concurrent OUD + CP imposes exceptional disease and clinical service burdens that likely require the development of simultaneous, integrated approaches to treatment. (PsycInfo Database Record (c) 2023 APA, all rights reserved).


Subject(s)
Chronic Pain , Opioid-Related Disorders , Veterans , Humans , Chronic Pain/drug therapy , Chronic Pain/epidemiology , Opioid-Related Disorders/epidemiology , Opioid-Related Disorders/drug therapy , Opioid-Related Disorders/psychology , Veterans/psychology , Delivery of Health Care , Cost of Illness , Analgesics, Opioid/therapeutic use
17.
Exp Clin Psychopharmacol ; 31(1): 37-45, 2023 Feb.
Article in English | MEDLINE | ID: mdl-35254839

ABSTRACT

A recent study demonstrated that during a single sampling period, 0.1 mg of intravenous (IV) nicotine (vs. placebo) was found to be the threshold for subjective and physiological drug effects. The present study is a secondary analysis evaluating whether the threshold for subjective and physiological effects is similar when the subject has repeated opportunities to choose blinded doses of nicotine versus placebo. We also examined whether cigarette craving, withdrawal, and rate of nicotine metabolism affected nicotine reinforcement, defined by a greater number of nicotine choices than placebo. Young adult (n = 34; 68% male), daily smokers had five laboratory sessions after overnight abstinence. After sampling an IV dose of nicotine (0.0125, 0.025, 0.05, 0.1, or 0.2 mg/70 kg) versus saline (placebo), participants completed a nicotine self-administration (NSA) procedure that included 10 opportunities to self-administer IV dose of nicotine or placebo. The threshold for subjective positive effects of nicotine during the NSA was equal to or lower than the sampling period, 0.05-0.1 mg versus 0.1 mg. The threshold for nicotine-induced heart rate increase was higher during the NSA than during the sampling period (0.2 mg vs. 0.1 mg). Higher baseline craving and nicotine metabolite ratio (NMR) were associated with nicotine reinforcement at 0.2 mg and 0.1 mg doses, respectively (p < .05). The results suggest that subjective effects during NSA are reported at doses lower than the sampling period. Taken together, tobacco products thought to be subthreshold for reinforcement should be carefully evaluated for their subjective effects, including their discriminative stimulus effects. (PsycInfo Database Record (c) 2023 APA, all rights reserved).


Subject(s)
Smoking Cessation , Tobacco Products , Tobacco Use Disorder , Young Adult , Male , Humans , Female , Nicotine , Smoking Cessation/methods , Nicotiana
18.
Pain Pract ; 23(4): 338-348, 2023 04.
Article in English | MEDLINE | ID: mdl-36527287

ABSTRACT

OBJECTIVE: Cognitive behavioral therapy for chronic pain (CBT-CP) is an evidence-based treatment for improving functioning and pain intensity for people with chronic pain with extensive evidence of effectiveness. However, there has been relatively little investigation of the factors associated with successful implementation and uptake of CBT-CP, particularly clinician and system level factors. This formative evaluation examined barriers and facilitators to the successful implementation and uptake of CBT-CP from the perspective of CBT-CP clinicians and referring primary care clinicians. METHODS: Qualitative interviews guided by the Consolidated Framework for Implementation Research were conducted at nine geographically diverse Veterans Affairs sites as part of a pragmatic clinical trial comparing synchronous, clinician-delivered CBT-CP and remotely delivered, technology-assisted CBT-CP. Analysis was informed by a grounded theory approach. RESULTS: Twenty-six clinicians (CBT-CP clinicians = 17, primary care clinicians = 9) from nine VA medical centers participated in individual qualitative interviews conducted by telephone from April 2019 to August 2020. Four themes emerged in the qualitative interviews: (1) the complexity and variability of referral pathways across sites, (2) referring clinician's lack of knowledge about CBT-CP, (3) referring clinician's difficulty identifying suitable candidates for CBT-CP, and (4) preference for interventions that can be completed from home. CONCLUSIONS: This formative evaluation identified clinician and system barriers to widespread implementation of CBT-CP and allowed for refinement of the subsequent implementation of two forms of CBT-CP in an ongoing pragmatic trial. Identification of relative difference in barriers and facilitators in the two forms of CBT-CP may emerge more clearly in a pragmatic trial that evaluates how treatments perform in real-world settings and may provide important information to guide future system-wide implementation efforts.


Subject(s)
Chronic Pain , Cognitive Behavioral Therapy , Self-Management , Telemedicine , Humans , Chronic Pain/therapy , Chronic Pain/psychology
19.
Pain Med ; 24(7): 846-854, 2023 07 05.
Article in English | MEDLINE | ID: mdl-36484691

ABSTRACT

BACKGROUND: Cognitive behavioral therapy for chronic pain (CBT-CP) has a strong evidence base, but little is known about when treatment benefits are achieved. The present study is a secondary analysis of individuals with chronic back pain recruited for a noninferiority trial comparing interactive voice response (IVR) CBT-CP with in-person CBT-CP. METHODS: On the basis of data from daily IVR surveys, a clinically meaningful change was defined as a 30% reduction in pain intensity (n = 108) or a 45% increase in daily steps (n = 104) compared with the baseline week. We identified individuals who achieved a meaningful change at any point during treatment, and then we compared those who maintained a meaningful change in their final treatment week (i.e., responders) with those who did not or who achieved a meaningful change but lapsed (i.e., nonresponders). RESULTS: During treatment, 46% of participants achieved a clinically meaningful decrease in pain intensity, and 66% achieved a clinically significant increase in number of steps per day. A total of 54% of patients were classified as responders in terms of decreases in pain intensity, and 70% were responders in terms of increases in step count. Survival analyses found that 50% of responders first achieved a clinically meaningful change by week 4 for pain intensity and week 2 for daily steps. Dropout and demographic variables were unrelated to responder status, and there was low agreement between the two measures of treatment response. CONCLUSIONS: Collectively, results suggest that most responders improve within 4 weeks. Evaluating treatment response is highly specific to the outcome measure, with little correlation across outcomes.


Subject(s)
Chronic Pain , Cognitive Behavioral Therapy , Self-Management , Humans , Chronic Pain/therapy , Chronic Pain/psychology , Cognitive Behavioral Therapy/methods , Outcome Assessment, Health Care , Surveys and Questionnaires , Treatment Outcome
20.
Nat Commun ; 13(1): 6523, 2022 11 22.
Article in English | MEDLINE | ID: mdl-36414617

ABSTRACT

Bacteria have the potential to translocate between sites in the human body, but the dynamics and consequences of within-host bacterial migration remain poorly understood. Here we investigate the link between gut and lung Pseudomonas aeruginosa populations in an intensively sampled ICU patient using a combination of genomics, isolate phenotyping, host immunity profiling, and clinical data. Crucially, we show that lung colonization in the ICU was driven by the translocation of P. aeruginosa from the gut. Meropenem treatment for a suspected urinary tract infection selected for elevated resistance in both the gut and lung. However, resistance was driven by parallel evolution in the gut and lung coupled with organ specific selective pressures, and translocation had only a minor impact on AMR. These findings suggest that reducing intestinal colonization of Pseudomonas may be an effective way to prevent lung infections in critically ill patients.


Subject(s)
Anti-Bacterial Agents , Pseudomonas aeruginosa , Humans , Pseudomonas aeruginosa/genetics , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/therapeutic use , Meropenem/pharmacology , Lung , Bacteria , Intensive Care Units
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