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1.
Elife ; 122024 Jul 16.
Article in English | MEDLINE | ID: mdl-39009040

ABSTRACT

Background: Prinflammatory extracellular chromatin from neutrophil extracellular traps (NETs) and other cellular sources is found in COVID-19 patients and may promote pathology. We determined whether pulmonary administration of the endonuclease dornase alfa reduced systemic inflammation by clearing extracellular chromatin. Methods: Eligible patients were randomized (3:1) to the best available care including dexamethasone (R-BAC) or to BAC with twice-daily nebulized dornase alfa (R-BAC + DA) for seven days or until discharge. A 2:1 ratio of matched contemporary controls (CC-BAC) provided additional comparators. The primary endpoint was the improvement in C-reactive protein (CRP) over time, analyzed using a repeated-measures mixed model, adjusted for baseline factors. Results: We recruited 39 evaluable participants: 30 randomized to dornase alfa (R-BAC +DA), 9 randomized to BAC (R-BAC), and included 60 CC-BAC participants. Dornase alfa was well tolerated and reduced CRP by 33% compared to the combined BAC groups (T-BAC). Least squares (LS) mean post-dexamethasone CRP fell from 101.9 mg/L to 23.23 mg/L in R-BAC +DA participants versus a 99.5 mg/L to 34.82 mg/L reduction in the T-BAC group at 7 days; p=0.01. The anti-inflammatory effect of dornase alfa was further confirmed with subgroup and sensitivity analyses on randomised participants only, mitigating potential biases associated with the use of CC-BAC participants. Dornase alfa increased live discharge rates by 63% (HR 1.63, 95% CI 1.01-2.61, p=0.03), increased lymphocyte counts (LS mean: 1.08 vs 0.87, p=0.02) and reduced circulating cf-DNA and the coagulopathy marker D-dimer (LS mean: 570.78 vs 1656.96 µg/mL, p=0.004). Conclusions: Dornase alfa reduces pathogenic inflammation in COVID-19 pneumonia, demonstrating the benefit of cost-effective therapies that target extracellular chromatin. Funding: LifeArc, Breathing Matters, The Francis Crick Institute (CRUK, Medical Research Council, Wellcome Trust). Clinical trial number: NCT04359654.


Subject(s)
Anti-Inflammatory Agents , COVID-19 Drug Treatment , COVID-19 , Deoxyribonuclease I , Humans , Male , Female , Deoxyribonuclease I/administration & dosage , Deoxyribonuclease I/therapeutic use , Middle Aged , Anti-Inflammatory Agents/administration & dosage , Anti-Inflammatory Agents/therapeutic use , Aged , Recombinant Proteins/administration & dosage , Recombinant Proteins/therapeutic use , Extracellular Traps/drug effects , SARS-CoV-2 , C-Reactive Protein/analysis , C-Reactive Protein/metabolism , Dexamethasone/administration & dosage , Dexamethasone/therapeutic use , Adult , Nebulizers and Vaporizers , Treatment Outcome , Administration, Inhalation
2.
Addict Neurosci ; 112024 Jun.
Article in English | MEDLINE | ID: mdl-38911873

ABSTRACT

While the majority of people with cocaine use disorders (CUD) also co-use tobacco/nicotine, most preclinical cocaine research does not include nicotine. The present study examined nicotine and cocaine co-use under several conditions of intravenous drug self-administration in monkeys, as well as potential peripheral biomarkers associated with co-use. In Experiment 1, male rhesus monkeys (N = 3) self-administered cocaine (0.001-0.1 mg/kg/injection) alone and with nicotine (0.01-0.03 mg/kg/injection) under a progressive-ratio schedule of reinforcement. When nicotine was added to cocaine, there was a significant leftward/upward shift in the number of injections received. In Experiment 2, socially housed female and male cynomolgus monkeys (N = 14) self-administered cocaine under a concurrent drug-vs-food choice schedule of reinforcement. Adding nicotine to the cocaine solution shifted the cocaine dose-response curves to the left, with more robust shifts noted in the female animals. There was no evidence of social rank differences. To assess reinforcing strength, delays were added to the presentation of drug; the co-use of nicotine and cocaine required significantly longer delays to decrease drug choice, compared with cocaine alone. Blood samples obtained post-session were used to analyze concentrations of neuronally derived small extracellular vesicles (NDE); significant differences in NDE profile were observed for kappa-opioid receptors when nicotine and cocaine were co-used compared with each drug alone and controls. These results suggest that drug interactions involving the co-use of nicotine and cocaine are not simply changing potency, but rather resulting in changes in reinforcing strength that should be utilized to better understand the neuropharmacology of CUD and the evaluation of potential treatments.

3.
Article in English | MEDLINE | ID: mdl-38760425

ABSTRACT

Considerable research has suggested that certain cognitive domains may contribute to cocaine misuse. However, there are gaps in the literature regarding whether cognitive performance before drug exposure predicts susceptibility to cocaine self-administration and how cognitive performance relates to future cocaine intake. Thus, the present study aimed to examine cognitive performance, as measured using automated CANTAB cognitive battery, prior to and following acquisition of cocaine self-administration under a concurrent drug vs. food choice procedure in female and male socially housed cynomolgus macaques. The cognitive battery consisted of measures of associative learning (stimulus and compound discrimination tasks), behavioral flexibility (intradimensional and extradimensional tasks), and behavioral inhibition (stimulus discrimination reversal, SDR, and extra-dimensional reversal tasks). After assessing cognitive performance, monkeys were trained to self-administer cocaine (saline, 0.01-0.1 mg/kg/injection) under a concurrent cocaine vs. food schedule of reinforcement. After a history of cocaine self-administration across 3-4 years, the cognitive battery was re-assessed and compared with sensitivity to cocaine reinforcement. Results showed drug-naïve monkeys that were less accurate on the SDR task, measuring behavioral inhibition, were more sensitive to cocaine reinforcement under the concurrent cocaine vs. food choice procedure. Furthermore, following chronic cocaine self-administration, cocaine intake was a negative predictor of accuracy on the SDR behavioral inhibition task. After cocaine maintenance, monkeys with higher cocaine intakes required more trials to complete the SDR behavioral inhibition task and made more incorrect responses during these trials. No sex or social rank differences were noted. Overall, these findings suggest that cognitive performance may influence vulnerability to cocaine misuse. Also, chronic cocaine may decrease levels of behavioral inhibition as measured via the SDR task in both females and males.

4.
Mol Divers ; 2024 Jan 19.
Article in English | MEDLINE | ID: mdl-38240950

ABSTRACT

Peptide-based therapeutics have been gaining attention due to their ability to actively target tumor cells. Additionally, several varieties of nucleotide derivatives have been developed to reduce cell proliferation and induce apoptosis of tumor cells. In this work, we have developed novel peptide conjugates with newly designed purine analogs and pyrimidine derivatives and explored the binding interactions with the kinase domain of wild-type EGFR and its mutant EGFR [L858R/ T790M] which are known to be over-expressed in tumor cells. The peptides explored included WNWKV (derived from sea cucumber) and LARFFS, which in previous work was predicted to bind to Domain I of EGFR. Computational studies conducted to explore binding interactions include molecular docking studies, molecular dynamics simulations and MMGBSA to investigate the binding abilities and stability of the complexes. The results indicate that conjugation enhanced binding capabilities, particularly for the WNWKV conjugates. MMGBSA analysis revealed nearly twofold higher binding toward the T790M/L858R double mutant receptor. Several conjugates were shown to have strong and stable binding with both wild-type and mutant EGFR. As a proof of concept, we synthesized pyrimidine conjugates with both peptides and determined the KD values using SPR analysis. The results corroborated with the computational analyses. Additionally, cell viability and apoptosis studies with lung cancer cells expressing the wild-type and double mutant proteins revealed that the WNWKV conjugate showed greater potency than the LARFFS conjugate, while LARFFS peptide alone showed poor binding to the kinase domain. Thus, we have designed peptide conjugates that show potential for further laboratory studies for developing therapeutics for targeting the EGFR receptor and its mutant T790M/L858R.

5.
Psychopharmacology (Berl) ; 241(2): 263-274, 2024 Feb.
Article in English | MEDLINE | ID: mdl-37882812

ABSTRACT

RATIONALE: Previous studies in socially housed monkeys examining acquisition of cocaine self-administration under fixed-ratio (FR) schedules of reinforcement found that subordinate males and dominant females were more vulnerable than their counterparts. OBJECTIVES: The present studies extended these findings in two ways: (1) to replicate the earlier study, in which female monkeys were studied after a relatively short period of social housing (~ 3 months) using cocaine-naïve female monkeys (n = 9; 4 dominant and 5 subordinate) living in well-established social groups (~ 18 months); and (2) in male monkeys (n = 3/social rank), we studied cocaine acquisition under a concurrent schedule, with an alternative, non-drug reinforcer available. RESULTS: In contrast to earlier findings, subordinate female monkeys acquired cocaine reinforcement (i.e., > saline reinforcement) at significantly lower cocaine doses compared with dominant monkeys. In the socially housed males, no dominant monkey acquired a cocaine preference (i.e., > 80% cocaine choice) over food, while two of three subordinate monkeys acquired cocaine reinforcement. In monkeys that did not acquire, the conditions were changed to an FR schedule with only cocaine available and after acquisition, returned to the concurrent schedule. In all monkeys, high doses of cocaine were chosen over food reinforcement. CONCLUSIONS: The behavioral data in females suggests that duration of social enrichment and stress can differentially impact vulnerability to cocaine reinforcement. The findings in socially housed male monkeys, using concurrent food vs. cocaine choice schedules of reinforcement, confirmed earlier social-rank differences using an FR schedule and showed that vulnerability could be modified by exposure to cocaine.


Subject(s)
Cocaine , Housing , Male , Female , Animals , Reinforcement, Psychology , Food , Self Administration , Reinforcement Schedule , Dose-Response Relationship, Drug
6.
Drug Alcohol Depend ; 251: 110952, 2023 10 01.
Article in English | MEDLINE | ID: mdl-37699287

ABSTRACT

BACKGROUND: Individuals who use cocaine have high rates of co-morbid alcohol use and when ethanol and cocaine are administered concurrently, the metabolite cocaethylene is formed. Cocaethylene is equipotent to cocaine in blocking dopamine reuptake and substitutes for cocaine in drug discrimination studies. However, no previous work has directly compared the reinforcing strength of cocaine to cocaethylene. METHODS: In Experiment 1, three individually-housed adult male rhesus macaques self-administer cocaine under a progressive-ratio (PR) schedule of reinforcement, during daily 4-hr sessions. Under this schedule, the primary dependent variable is the number of injections received, or the break point (BP). Saline, cocaine (0.001-0.3mg/kg/injection) and cocaethylene (0.0003-0.1mg/kg/injection) dose-response curves were determined. In Experiment 2, two female cynomolgus and one rhesus macaque responded under a concurrent schedule of drug (cocaine or cocaethylene) vs. 1.0-g banana-flavored food pellets, during daily 1-hr sessions. RESULTS: Both cocaine and cocaethylene functioned as reinforcers under the PR and concurrent choice schedules of reinforcement. Under the PR schedule, peak BPs were not significantly different, nor were ED50 values on the ascending limb, suggesting that cocaethylene has equal reinforcing strength and potency to cocaine. Under the concurrent drug-food choice procedure, cocaethylene was also equally potent to cocaine. CONCLUSIONS: Under two schedules of reinforcement designed to assess reinforcing strength, cocaethylene and cocaine were equipotent and of equal reinforcing strength. Because cocaethylene has a longer duration of action, it is important for studies designed to evaluate treatments for cocaine use to also consider the effects of these interventions on cocaethylene.


Subject(s)
Cocaine , Animals , Male , Female , Macaca mulatta , Self Administration , Dose-Response Relationship, Drug , Cocaine/pharmacology , Reinforcement Schedule
7.
Neuropsychopharmacology ; 48(10): 1436-1445, 2023 09.
Article in English | MEDLINE | ID: mdl-37349473

ABSTRACT

Brain imaging studies using positron emission tomography (PET) have shown that long-term cocaine use is associated with lower levels of dopamine (DA) D2/D3 receptors (D2/D3R); less consistent are the effects on DA transporter (DAT) availability. However, most studies have been conducted in male subjects (humans, monkeys, rodents). In this study, we used PET imaging in nine drug-naïve female cynomolgus monkeys to determine if baseline measures of DAT, with [18F]FECNT, and D2/D3R availability, with [11C]raclopride, in the caudate nucleus, putamen and ventral striatum were associated with rates of cocaine self-administration and if these measures changed during long-term (~13 months) cocaine self-administration and following time-off (3-9 months) from cocaine. Cocaine (0.2 mg/kg/injection) and 1.0 g food pellets were available under a multiple fixed-interval (FI) 3-min schedule of reinforcement. In contrast to what has been observed in male monkeys, baseline D2/D3R availability was positively correlated with rates of cocaine self-administration only during the first week of exposure; DAT availability did not correlate with cocaine self-administration. D2/D3R availability decreased ~20% following cumulative intakes of 100 and 1000 mg/kg cocaine; DAT availability did not significantly change. These reductions in D2/D3R availability did not recover over 9 months of time-off from cocaine. To determine if these reductions were reversible, three monkeys were implanted with osmotic pumps that delivered raclopride for 30 days. We found that chronic treatment with the D2/D3R antagonist raclopride increased D2/D3R availability in the ventral striatum but not in the other regions when compared to baseline levels. Over 13 months of self-administration, tolerance did not develop to the rate-decreasing effects of self-administered cocaine on food-reinforced responding, but number of injections and cocaine intake significantly increased over the 13 months. These data extend previous findings to female monkeys and suggest sex differences in the relationship between D2/D3R availability related to vulnerability and long-term cocaine use.


Subject(s)
Cocaine , Positron-Emission Tomography , Haplorhini , Animals , Female , Positron-Emission Tomography/methods , Dopamine Plasma Membrane Transport Proteins , Receptors, Dopamine D3 , Cocaine/administration & dosage , Cocaine/adverse effects , Self Administration , Raclopride
8.
mBio ; 14(2): e0046423, 2023 04 25.
Article in English | MEDLINE | ID: mdl-37010413

ABSTRACT

Moraxella catarrhalis is found almost exclusively within the human respiratory tract. This pathobiont is associated with ear infections and the development of respiratory illnesses, including allergies and asthma. Given the limited ecological distribution of M. catarrhalis, we hypothesized that we could leverage the nasal microbiomes of healthy children without M. catarrhalis to identify bacteria that may represent potential sources of therapeutics. Rothia was more abundant in the noses of healthy children compared to children with cold symptoms and M. catarrhalis. We cultured Rothia from nasal samples and determined that most isolates of Rothia dentocariosa and "Rothia similmucilaginosa" were able to fully inhibit the growth of M. catarrhalis in vitro, whereas isolates of Rothia aeria varied in their ability to inhibit M. catarrhalis. Using comparative genomics and proteomics, we identified a putative peptidoglycan hydrolase called secreted antigen A (SagA). This protein was present at higher relative abundance in the secreted proteomes of R. dentocariosa and R. similmucilaginosa than in those from non-inhibitory R. aeria, suggesting that it may be involved in M. catarrhalis inhibition. We produced SagA from R. similmucilaginosa in Escherichia coli and confirmed its ability to degrade M. catarrhalis peptidoglycan and inhibit its growth. We then demonstrated that R. aeria and R. similmucilaginosa reduced M. catarrhalis levels in an air-liquid interface culture model of the respiratory epithelium. Together, our results suggest that Rothia restricts M. catarrhalis colonization of the human respiratory tract in vivo. IMPORTANCE Moraxella catarrhalis is a pathobiont of the respiratory tract, responsible for ear infections in children and wheezing illnesses in children and adults with chronic respiratory diseases. Detection of M. catarrhalis during wheezing episodes in early life is associated with the development of persistent asthma. There are currently no effective vaccines for M. catarrhalis, and most clinical isolates are resistant to the commonly prescribed antibiotics amoxicillin and penicillin. Given the limited niche of M. catarrhalis, we hypothesized that other nasal bacteria have evolved mechanisms to compete against M. catarrhalis. We found that Rothia are associated with the nasal microbiomes of healthy children without Moraxella. Next, we demonstrated that Rothia inhibit M. catarrhalis in vitro and on airway cells. We identified an enzyme produced by Rothia called SagA that degrades M. catarrhalis peptidoglycan and inhibits its growth. We suggest that Rothia or SagA could be developed as highly specific therapeutics against M. catarrhalis.


Subject(s)
Asthma , Moraxella catarrhalis , Child , Adult , Humans , Peptidoglycan/metabolism , Respiratory Sounds
9.
Pharmacol Biochem Behav ; 225: 173545, 2023 04.
Article in English | MEDLINE | ID: mdl-37004977

ABSTRACT

Cocaine use disorder (CUD) is a significant problem worldwide, with no FDA-approved treatments. Epidemiological data indicate that only about 17 % of people that use cocaine will meet DSM criteria for CUD. Thus, the identification of biomarkers predictive of eventual cocaine use may be of great value. Two potentially useful predictors of CUD are social hierarchies in nonhuman primates and delay discounting. Both social rank and preference for a smaller, immediate reinforcer relative to a larger, delayed reinforcer have been predictive of CUD. Therefore, we wanted to determine if there was also a relationship between these two predictors of CUD. In the present study, monkeys cocaine-naive responded under a concurrent schedule of 1- vs. 3-food pellets and delivery of the 3-pellet option was delayed. The primary dependent variable was the indifference point (IP), which is the delay that results in 50 % choice for both options. In the initial determination of IP, there were no differences based on sex or social rank of the monkeys. When the delays were redetermined after ~25 baseline sessions (range 5-128 sessions), dominant females and subordinate males showed the largest increases in IP scores from the first determination to the second. Because 13 of these monkeys had prior PET scans of the kappa opioid receptor (KOR), we examined the relationship between KOR availability and IP values and found that the change in IP scores from the first to the second determination significantly negatively predicted average KOR availability in most brain regions. Future studies will examine acquisition to cocaine self-administration in these same monkeys, to determine if IP values are predictive of vulnerability to cocaine reinforcement.


Subject(s)
Cocaine , Delay Discounting , Animals , Male , Female , Macaca fascicularis , Receptors, Opioid, kappa , Choice Behavior , Cocaine/pharmacology , Phenotype , Self Administration , Dose-Response Relationship, Drug
10.
Neuropsychopharmacology ; 48(12): 1716-1723, 2023 11.
Article in English | MEDLINE | ID: mdl-37118057

ABSTRACT

Recent studies suggest that dopamine D3 receptors (D3R) may be a therapeutic target for opioid use disorders (OUD). This study examined the effects of the D3R partial agonist (±)VK4-40 and the D3R-selective antagonist (±)VK4-116, compared to the mu-opioid receptor antagonist naltrexone (NTX), in nonhuman primate models of OUD and antinociception. Adult male and female (N = 4/sex) cynomolgus monkeys were trained to self-administer oxycodone (0.003-0.1 mg/kg/injection) first under a fixed-ratio (FR) and then a progressive-ratio (PR) schedule of reinforcement during daily 1- and 4-hr sessions, respectively. Under the FR schedule, intravenous NTX (0.01-0.1 mg/kg), (±)VK4-116 (1.0-10 mg/kg), and (±)VK4-40 (1.0-10 mg/kg) were studied in combination with the peak oxycodone dose and a dose on the descending limb of the dose-effect curve; NTX and (±)VK4-40 were also studied at the peak of the PR dose-response curve (N = 4). Following saline extinction, each compound was examined on oxycodone-induced reinstatement. Finally, these compounds were assessed in adult male rhesus monkeys (N = 3) in a warm-water (38 °C, 50 °C, 54 °C) tail withdrawal assay. NTX decreased responding on the peak of the FR oxycodone dose-response curve, but increased responding on the descending limb. (±)VK4-40, but not (±)VK4-116, significantly decreased peak oxycodone self-administration; (±)VK4-40 did not increase responding on the descending limb. NTX and (±)VK4-40, but not (±)VK4-116, attenuated oxycodone-induced reinstatement. Under PR responding, NTX and (±)VK4-40 decreased breakpoints. Oxycodone-induced antinociception was attenuated by NTX, but not by (±)VK4-40 or (±)VK4-116. Together, these results suggest that further research evaluating the effects of (±)VK4-40 as a novel pharmacotherapy for OUD is warranted.


Subject(s)
Opioid-Related Disorders , Oxycodone , Receptors, Dopamine D3 , Animals , Female , Male , Analgesics, Opioid/pharmacology , Dopamine Agonists/pharmacology , Dopamine Antagonists/pharmacology , Dose-Response Relationship, Drug , Naltrexone/pharmacology , Oxycodone/administration & dosage , Receptors, Dopamine D3/drug effects , Self Administration , Macaca fascicularis
11.
Mult Scler Relat Disord ; 70: 104501, 2023 Feb.
Article in English | MEDLINE | ID: mdl-36621161

ABSTRACT

BACKGROUND: The link between tobacco smoking and Multiple Sclerosis (MS) onset and progression is well-established. While clinical levels of depression and anxiety are highly prevalent in people living with MS (plwMS), and both are recognized as common MS-related symptoms, the relationships between smoking behavior and depression and anxiety are unclear. This systematic review aimed to synthesize evidence on the relationships between current-smoking and former-smoking and depression and anxiety in plwMS. METHODS: Systematic review of all studies investigating associations between tobacco smoking and depression and anxiety in plwMS was conducted. Relevant studies published before 26 April 2022 were identified by searching seven databases; MEDLINE® (Ovid and PubMed), Embase, CINAHL®, Cochrane Library and PsycInfo), and citation and reference list checking. Joanna Briggs Institute Critical Appraisal Checklists for respective study designs assessed the risk of bias. RESULTS: Thirteen publications reporting on 12 studies met study inclusion criteria. Nine of 12 studies examining current-smoking and depression in plwMS identified a positive association. Four prospective studies provided evidence supporting a causal smoking-depression relationship, with 1.3-2.3-fold higher depression prevalence found in current-smokers than non-smokers. Three cross-sectional studies found no smoking-depression association. Four of five included studies found current-smoking was associated with anxiety, with three prospective studies indicating anxiety prevalence was around 20% higher in current-smokers. Former-smoking was associated with increased prevalence of depression, but not anxiety. CONCLUSION: We provide strong evidence for increased depression prevalence in plwMS who are either current-smokers or former-smokers. However, only current-smoking was associated with increased prevalence of anxiety.


Subject(s)
Depression , Multiple Sclerosis , Humans , Depression/epidemiology , Cross-Sectional Studies , Prospective Studies , Tobacco Smoking
12.
J Cancer Res Clin Oncol ; 149(1): 25-46, 2023 Jan.
Article in English | MEDLINE | ID: mdl-36251064

ABSTRACT

BACKGROUND: Lynch-like syndrome (LLS) tumors have similar clinicopathological features to Lynch syndrome (LS) tumors but have no identifiable pathogenic germline mismatch repair gene variant. However, cancer risks in LLS patients and first-degree relatives (FDRs) are not well defined. METHODS: To clarify LLS-associated cancer risks, a systematic review of all studies examining all cancer risks in LLS was performed. Searching of Medline, Embase, Pubmed, Cochrane and CINAHL databases and reference/citation checking identified relevant studies published between January 1, 1980 and February 11, 2021. Joanna Briggs Institute Appraisal Tools assessed the risk of bias. RESULTS: Six studies (five cohort/one cross-sectional) were eligible for study inclusion. One study found no difference in colorectal cancer (CRC) incidence between LLS and LS patients or CRC risks at aged 70 years. Three studies found CRC incidence in LLS FDRs was higher than the general population but lower than LS FDRs. Two studies showed no difference in CRC diagnosis age between LLS patients and LS patients. Endometrial cancer risks in LLS patients were higher than the general population but lower than LS patients. CONCLUSION: Evidence of elevated CRC risks in LLS patients and FDRs supports increased colonoscopy surveillance strategies for LLS patients and FDRs in line with current recommendations for LS. Due to heterogeneity amongst LLS populations, extended intervals between screening may be advised for low-risk families. Studies to resolve the molecular characterization and definition of LLS are needed to clarify cancer risks associated with LLS which in turn may individualize surveillance strategies for LLS patients and families.


Subject(s)
Colorectal Neoplasms, Hereditary Nonpolyposis , Colorectal Neoplasms , Endometrial Neoplasms , Female , Humans , Cross-Sectional Studies , Microsatellite Instability , Colorectal Neoplasms, Hereditary Nonpolyposis/genetics , Colorectal Neoplasms, Hereditary Nonpolyposis/diagnosis , Colorectal Neoplasms, Hereditary Nonpolyposis/epidemiology , Germ-Line Mutation , DNA Mismatch Repair
13.
Immunity ; 55(12): 2436-2453.e5, 2022 12 13.
Article in English | MEDLINE | ID: mdl-36462503

ABSTRACT

The factors that influence survival during severe infection are unclear. Extracellular chromatin drives pathology, but the mechanisms enabling its accumulation remain elusive. Here, we show that in murine sepsis models, splenocyte death interferes with chromatin clearance through the release of the DNase I inhibitor actin. Actin-mediated inhibition was compensated by upregulation of DNase I or the actin scavenger gelsolin. Splenocyte death and neutrophil extracellular trap (NET) clearance deficiencies were prevalent in individuals with severe COVID-19 pneumonia or microbial sepsis. Activity tracing by plasma proteomic profiling uncovered an association between low NET clearance and increased COVID-19 pathology and mortality. Low NET clearance activity with comparable proteome associations was prevalent in healthy donors with low-grade inflammation, implicating defective chromatin clearance in the development of cardiovascular disease and linking COVID-19 susceptibility to pre-existing conditions. Hence, the combination of aberrant chromatin release with defects in protective clearance mechanisms lead to poor survival outcomes.


Subject(s)
COVID-19 , Sepsis , Animals , Mice , Actins , Chromatin , Deoxyribonuclease I , DNA , Neutrophils , Proteomics
14.
J Res Nurs ; 27(6): 532-542, 2022 Nov.
Article in English | MEDLINE | ID: mdl-36338927

ABSTRACT

Background: Neurological patients often suffer physical, cognitive, communicative, behavioural or psychosocial limitations. This may weaken the preconditions for participating in decisions about their treatment, rehabilitation and future. These impairments often cause relatives to care and advocate for the patient. This practice was gravely interrupted by the COVID-19 visitor ban. Aims: This study aims to investigate how relatives of neurological patients experienced the visitor ban and to identify potential areas for improvement. Methods: Twelve semi-structured interviews with relatives of neurological patients were conducted. Data were analysed by performing a thematic analysis inspired by Braun and Clark. Results: The following six themes emerged: Visitor ban as a necessary evil, Losing control and feeling checkmate, Mending the information gap, Waiting by the phone, Empathy and compassion as the core of a good relationship and Caring for a loved one from a distance. Conclusions: Having a loved one admitted to a neurological ward during the COVID-19 visitor ban greatly restrains relatives and affects the relationship with their loved one and the hospital healthcare staff. Healthcare staff need to take responsibility and reach out, while simultaneously exploring new ways of communicating.

15.
S Afr J Surg ; 60(3): 204-206, 2022 Sep.
Article in English | MEDLINE | ID: mdl-36155377

ABSTRACT

SUMMARY: We present a case of a young male patient with no previously known medical, surgical or psychiatric history, who was referred to our institution as an irreducible left inguinal hernia with signs of strangulation. Intraoperative findings, however, revealed a retained foreign body at the rectosigmoid junction, which had previously perforated through the floor of the inguinal canal, essentially sealing off the contamination into the inguinal canal and contributing to the clinical presentation of a left inguinal hernia. This is, to our knowledge, the first published case report locally and internationally concerning rectosigmoid-inguinal canal perforation with the working end of a screwdriver.


Subject(s)
Hernia, Inguinal , Colon, Sigmoid/diagnostic imaging , Colon, Sigmoid/surgery , Hernia, Inguinal/complications , Hernia, Inguinal/diagnosis , Hernia, Inguinal/surgery , Humans , Male
16.
Nat Commun ; 13(1): 4658, 2022 08 09.
Article in English | MEDLINE | ID: mdl-35945238

ABSTRACT

The mechanisms linking systemic infection to hyperinflammation and immune dysfunction in sepsis are poorly understood. Extracellular histones promote sepsis pathology, but their source and mechanism of action remain unclear. Here, we show that by controlling fungi and bacteria captured by splenic macrophages, neutrophil-derived myeloperoxidase attenuates sepsis by suppressing histone release. In systemic candidiasis, microbial capture via the phagocytic receptor SIGNR1 neutralizes myeloperoxidase by facilitating marginal zone infiltration and T cell death-dependent histone release. Histones and hyphae induce cytokines in adjacent CD169 macrophages including G-CSF that selectively depletes mature Ly6Ghigh neutrophils by shortening their lifespan in favour of immature Ly6Glow neutrophils with a defective oxidative burst. In sepsis patient plasma, these mediators shorten mature neutrophil lifespan and correlate with neutrophil mortality markers. Consequently, high G-CSF levels and neutrophil lifespan shortening activity are associated with sepsis patient mortality. Hence, by exploiting phagocytic receptors, pathogens degrade innate and adaptive immunity through the detrimental impact of downstream effectors on neutrophil lifespan.


Subject(s)
Neutrophils , Sepsis , Granulocyte Colony-Stimulating Factor/metabolism , Histones/metabolism , Humans , Longevity , Macrophages/metabolism , Peroxidase/metabolism , T-Lymphocytes/metabolism
17.
Qual Health Res ; 32(8-9): 1356-1369, 2022 07.
Article in English | MEDLINE | ID: mdl-35603563

ABSTRACT

This current study explored the lived experiences of patients with long-term cognitive sequelae after recovering from COVID-19. A qualitative design with in-depth interviews and an analysis inspired by Ricoeur's interpretation theory was utilised. Contracting COVID-19 and suffering long-term sequelae presented as a life-altering event with significant consequences for one's social, psychological and vocational being in the world in the months following the infection. Patients living with long-term cognitive sequelae after COVID-19 were in an unknown life situation characterised by feelings of anxiety, uncertainty and concerns about the future, significantly disrupting their life trajectory and forcing them to change their ways of life. While awaiting studies on treatment, symptom management and recovery after persistent sequelae of COVID-19, clinicians and researchers may find inspiration in experiences of other health conditions with similar phenomenology, such as ME/chronic fatigue syndrome and chronic headaches.


Subject(s)
COVID-19 , Fatigue Syndrome, Chronic , Anxiety/etiology , Cognition , Humans , Qualitative Research , Uncertainty
18.
Preprint in English | medRxiv | ID: ppmedrxiv-22272888

ABSTRACT

BackgroundSARS-CoV2 infection causes severe, life-threatening pneumonia. Hyper-inflammation, coagulopathy and lymphopenia are associated with pathology and poor outcomes in these patients. Cell-free (cf) DNA is prominent in COVID-19 patients, amplifies inflammation and promotes coagulopathy and immune dysfunction. We hypothesized that cf-DNA clearance by nebulised dornase alfa may reduce inflammation and improve disease outcomes. Here, we evaluated the efficacy of nebulized dornase alfa in patients hospitalised with severe COVID-19 pneumonia. MethodsIn this randomised controlled single-centre phase 2 proof-of-concept trial, we recruited adult patients admitted to hospital that exhibited stable oxygen saturation ([≥]94%) on supplementary oxygen and a C-reactive protein (CRP) level [≥]30mg/L post dexamethasone treatment. Participants were randomized at a 3:1 ratio to receive twice-daily nebulised dornase alfa in addition to best available care (BAC) or BAC alone for seven days or until hospital discharge. A 2:1 ratio of historical controls to treated individuals (HC, 2:1) were included as the primary endpoint comparators. The primary outcome was a reduction in systemic inflammation measured by blood CRP levels over 7 days post-randomisation, or to discharge if sooner. Secondary and exploratory outcomes included time to discharge, time on oxygen, D-dimer levels, lymphocyte counts and levels of circulating cf-DNA. ResultsWe screened 75 patients and enrolled 39 participants out of which 30 in dornase alfa arm, and 9 in BAC group. We also matched the recruited patients in the treated group (N=30) to historical controls in the BAC group (N=60). For the the primary outcome, 30 patients in the dornase alfa were compared to 69 patients in the BAC group. Dornase alfa treatment reduced CRP by 33% compared to the BAC group at 7-days (P=0.01). The dornase alfa group least squares mean CRP was 23.23 mg/L (95% CI 17.71 to 30.46) and the BAC group 34.82 mg/L (95% CI 28.55 to 42.47). A significant difference was also observed when only randomised participants were compared. Furthermore, compared to the BAC group, the chance of live discharge was increased by 63% in the dornase alfa group (HR 1.63, 95% CI 1.01 to 2.61, P=0.03), lymphocyte counts were improved (least-square mean: 1.08 vs 0.87, P=0.02) and markers of coagulopathy such as D-dimer were diminished (least-square mean: 570.78 vs 1656.96g/mL, P=0.004). Moreover, the dornase alfa group exhibited lower circulating cf-DNA levels that correlated with CRP changes over the course of treatment. No differences were recorded in the rates and length of stay in the ICU or the time on oxygen between the groups. Dornase alfa was well-tolerated with no serious adverse events reported. ConclusionsIn this proof-of-concept study in patients with severe COVID-19 pneumonia, treatment with nebulised dornase alfa resulted in a significant reduction in inflammation, markers of immune pathology and time to discharge. The effectiveness of dornase alfa in patients with acute respiratory infection and inflammation should be investigated further in larger trials.

19.
Mol Divers ; 26(5): 2717-2743, 2022 Oct.
Article in English | MEDLINE | ID: mdl-35037187

ABSTRACT

In this work, for the first time, we designed derivatives of beta-D-glucosyloxy-3-hydroxy-trans-stiblene-2-carboxylic acid (GHS), by conjugating GHS with tumor targeting peptides RPARPAR and GGKRPAR to target over-expressed receptors in tumor cells. The sequences RPARPAR and GGKRPAR are known to target the neuropilin1 (NRP1) receptor due to the C-terminal Arg domain; however, their effectiveness has never been examined with other commonly over-expressed receptors in tumor cells, particularly of chronic lymphocytic leukemia that include integrin α1ß1 and CD22. By conjugating these peptides with GHS, which is known for its inherent anti-cancer properties, the goal is to further enhance tumor cell targeting by developing compounds that can target multiple receptors. The physicochemical properties of the conjugates and individual peptides were analyzed using Turbomole and COSMOthermX20 in order to determine their hydrogen bond accepting and donating capabilities. The web server POCASA was used in order to determine the surface cavities and binding pockets of the three receptors. To explore the binding affinities, we conducted molecular docking studies with the peptides and the conjugates with each of the receptors. After molecular docking, the complexes were analyzed using Protein-Ligand Interaction Profiler to determine the types of interactions involved. Molecular dynamics simulation studies were conducted to explore the stability of the receptor-ligand complexes. Our results indicated that in most cases the conjugates showed higher binding and stability with the receptors. Additionally, highly stable complexes of conjugates were obtained with CD22, NRP1 and in most cases with the integrin α1ß1 receptor as well. The binding energies were calculated for each of the receptor ligand complexes through trajectory analysis using MMGBSA studies. SwissADME studies revealed that the compounds showed low GI absorption and were not found to be CYP inhibitors and had bioavailability score that would allow them to be considered as potential drug candidates. Overall, our results for the first time show that the designed conjugates can target multiple over-expressed receptors in tumor cells and may be potentially developed as future therapeutics for targeting tumor cells.


Subject(s)
Molecular Dynamics Simulation , Stilbenes , Carboxylic Acids , Integrin alpha1beta1 , Ligands , Molecular Docking Simulation , Peptides/chemistry , Peptides/pharmacology , Protein Binding
20.
Preprint in English | medRxiv | ID: ppmedrxiv-22269616

ABSTRACT

Hyperinflammation, coagulopathy and immune dysfunction are prominent in patients with severe infections. Extracellular chromatin clearance by plasma DNases suppresses such pathologies in mice but whether severe infection interferes with these pathways is unclear. Here, we show that patients with severe SARS-CoV-2 infection or microbial sepsis exhibit low extracellular DNA clearance capacity associated with the release of the DNase inhibitor actin. Unlike naked DNA degradation (DNase), neutrophil extracellular trap degradation (NETase) was insensitive to G-actin, indicating distinct underlying mechanisms. Activity-based proteomic profiling of severely ill SARS-CoV-2 patient plasma revealed that patients with high NETase and DNase activities exhibited 18-fold higher survival compared to patients with low activity proteomic profiles. Remarkably, low DNA clearance capacity was also prominent in healthy individuals with chronic inflammation, suggesting that pre-existing inflammatory conditions may increase the risk for mortality upon infection. Hence, functional proteomic profiling illustrates that non-redundant DNA clearance activities protect critically ill patients from mortality, uncovering protein combinations that can accurately predict mortality in critically ill patients.

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